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Influenza - Science topic

This group is for discussion about any influenza research related topics
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This RG open question is linked to the previous about the dramatic evolution (partly unexplainable) of COVID19 in Northern Italy during wave 1.
The previous RG open question is reported below🔴 and resulted in a completely alternative model for the evolution🟨 of SARS-CoV/2 from pre-pandemic phase to pandemic phase.
In this specific RG question, the intention is to create an open discussion on the possible emergence of a violent outbreak of avian flu or similar in central Europe.
This concern arises from a qualitative model that links three events which in the past have always characterized the violent explosion of a bird flu or similar.
---Coronavirus Epidemic/Pandemic;
---Conflict/War partly out of control;
---Pandemic avian flu or similar.
The ABSTRACT of the model can be consulted directly here.. https://www.researchgate.net/figure/46_fig2_367046404
This RG open question will serve to accumulate data both for and against this dire possibility.
Thanks to all the participants.
|--sv--|
🔴The novel Coronavirus in N. Italy, Lombardia 【 COVID19 / 2019nCoV / SARSCoV2 】 shows a fatality rate compatible with SARS-MERS. Why?? MAR.2020. -- https://www.researchgate.net/post/The-novel-Coronavirus-in-N-Italy-Lombardia-COVID19-2019nCoV-SARSCoV2-shows-a-fatality-rate-compatible-with-SARS-MERS-Why
🟨Link between the start of pandemic SARS-CoV/2 (COVID19) and the Huanan Seafood Wholesale Market in Wuhan (Hubei: China): the furin cleavage site of spike protein. FEB.2022. -- https://www.researchgate.net/publication/358443761
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I have a question. Do prior immunity to a virus-like particle vaccine platform affects its immunogenicity for the next vaccination? For example, if we vaccinate an individual using a chimeric VLP consist of an antigen of interest fused into influenza M1 protein as the core, will it have a lower immune response if the individual were vaccinated with other VLP-based vaccine containing the same M1 protein? Will it happen as with the viral vector vaccine?
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The relationship betwween the efficacy of prior immunity and vaccine depends on titer of prior immuinty due to previous vaccination or infection ,if protective titer no need for vaccination ,if not protctive vaccine needed
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Hi Dear researcher
Some Influenza subtypes are recommended for vaccination by WHO. Unfortunately the current database of influenza have not update sequences about influenza. could you help me to find the protein sequences of following subtypes?
H1N1 A/Sydney/5/2021 (H1N1)pdm09-like virus
H3N2 A/Darwin/6/2021 (MDCK-SIAT derived)
B/Austria/1359417/2021 (MDCK derived)
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The isolation of substational numbers of viral sequence variants at highly variable viral protein domains remain a major challanges ,several trials depends on the following......increase sucess of gene cloning and streamline the proces of futural engenineering of novel viral variants ....Clustred randsmization in a full length gene......Stsbilizating of thr clones and reduction of stress on host cells......The use of poission diztribution is proposed to approxametly sequencing out put to achivd coast effectivess
For more detailed see the attached ref.https://www.Sciencedirect.com/sci.
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Hi frds,
does the Influenza virus have more immune escaping properties than the new Covid-Variants? May they develop similarly unpredictable in the future?
Cherish your feedback.
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The results of such cases is Co_infections ond other clinical characteric of Covid_19 in patients and other respiratory disorders.
More detailed in attached ref.
Wu Q.,et al.Co_infections and other clinical characterices of Covid_19 in Children.Pediatrics2o2o;146(1)
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Hi frds,
are any memory T cells involved in fighting Influenza?
How come that no real vaccine is there for Influenza? Is the influenza-Virus mutating so fast that there is an immune escape involved?
Cherish your feedback.
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Also, kindly check:
Memory killer T cells are primed in the spleen during influenza infection:
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Hi frds,
if an immune escaping virus develops faster than our memory T-Cells, do memory T cells have an impact on fighting the virus? Guess the naive T cells have no impact?
Cherish your feedback.
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Yes
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I am wondering if the use of collagen as a matrix on the plate, or other matrix, with the consequent cell polarization, is necessary to get good virus yields. Many studies does not report culture on collagen or other matrix.
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Thank you !!
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I plan to use BALB/c mice for studying pneumonia caused by the mouse-adapted influenza virus (A/PR8/H1N1).
I want to know, what is the requirement to determine the sex of an animal? ​It seems that most of them choose female mice, but there are also researchers who use half male and female mice. What is the difference between them? Does the sex of the mouse have a significant impact on the final result?
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One of the main issues using male mice (and housing several in the same cage) is that they tend to fight with each other. If this occurs, they need to be separated and placed into individual cages. This could certainly impact the results of your study.
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Information provided by (Responsible Party):
ZhiYong Peng, Zhongnan Hospital
Brief Summary:
2019 new coronavirus (2019-nCoV) infected pneumonia, namely severe acute respiratory infection (SARI) has caused global concern and emergency. There is a lack of effective targeted antiviral drugs, and symptomatic supportive treatment is still the current main treatment for SARI.
Vitamin C is significant to human body and plays a role in reducing inflammatory response and preventing common cold. In addition, a few studies have shown that vitamin C deficiency is related to the increased risk and severity of influenza infections.
We hypothesize that Vitamin C infusion can help improve the prognosis of patients with SARI. Therefore, it is necessary to study the clinical efficacy and safety of vitamin C for the clinical management of SARI through randomized controlled trials during the current epidemic of SARI.
Vitamin C, also known as ascorbic acid, has antioxidant properties. When sepsis happens, the cytokine surge caused by sepsis is activated, and neutrophils in the lungs accumulate in the lungs, destroying alveolar capillaries. Early clinical studies have shown that vitamin C can effectively prevent this process. In addition, vitamin C can help to eliminate alveolar fluid by preventing the activation and accumulation of neutrophils, and reducing alveolar epithelial water channel damage.
At the same time, vitamin C can prevent the formation of neutrophil extracellular traps, which is a biological event of vascular injury caused by neutrophil activation. Vitamins can effectively shorten the duration of the common cold. In extreme conditions (athletes, skiers, art workers, military exercises), it can effectively prevent the common cold.
And whether vitamin C also has a certain protective effect on influenza patients, only few studies have shown that vitamin C deficiency is related to the increased risk and severity of influenza infections. In a controlled but non-randomized trial, 85% of the 252 students treated experienced a reduction in symptoms in the high-dose vitamin C group (1g / h at the beginning of symptoms for 6h, followed by 3 * 1g / day).
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Do we need adapt influenza viruses in MDCK cells before conducting serum neutralization test with influenza viruses in MDCK cels?? Thanks
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Thank you..
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C19 tests may show cross reactivity or interference with other viruses
CR: human coronavirus 229E, human coronavirus OC43, human coronavirus NL63, MERS coronavirus
IF: Influenza A, B; RSV, Protein A-positive Staphylococcus aureus
Is there any laboratory which is capable to test these?
Kind regards,
Dietrich Doll
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The different coronaviruses can be determined and differentiated by PCR-based sequencing technologies, which are available at research institutions and some diagnostic laboratories.
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From 40 to 64 years of age, about 92,000 people have died or at least their deaths are attributed to Covid in the United States alone. https://www.statista.com/statistics/1191568/reported-deaths-from-covid-by-age-us/ If the new variants are as reported this disease is evolving to a more lethal version that kills younger patients https://www.cnbc.com/2021/03/11/covid-variant-in-the-uk-appears-to-be-64percent-more-deadly-than-other-strains-study-finds.html This begs serious questions did our defensive measures hand washing, masks, and quarantines encourage this trend to appear. Certainly, the modern practice of clustering or warehousing elderly members of society allowed the virus to specialize in rapid reproduction very similar to what happened to Spanish influenza in the trenches of WW1. Reports of unmitigated stress, binge eating, monthly weight gain lend credence that confinement might have been counterproductive. Indeed, some might argue that had we done no quarantining we would have gained herd immunity by now. Instead, are we giving Covid the time to evolve each time it breaks into a protected sector of the population? Please feel free to debate this question in the replies.
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I think there is evidence that the measures put in place against the virus are working. The vaccines are also helping a lot, although some of them have adverse side effects.
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Dear Fellows
With the developing stories of the spread of COVID-19 all around the world, which has been declared as a pandemic by WHO recently, I am wondering, in how much time this virus would vanish from the surface of the Earth? Is there any scientific study available for this?
Please share your opinions.
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Todavía no se puede predecir q desaparecerá el Covid 19. Al parecer tendremos q convivir con él e inmunizarnos con las vacunas aprobadas por la OMS.
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Hello,
I have recently started to do some Plaque assays to determine Influenza titer. However, my plaques dont really look nice and are therefore hard to count, so I wanted to ask if someone has some suggestions to improve that.
Some Info: I use MDCK-II cells in 96-well plates for infection and after a 1 hour infection period I incubate these for 28 hours with an 50/50 mixture of Avicel/2xMEM + Trypsin.
I have attached a picture of one of my assays so you can see that sometimes the layer of cells seems to be disrupted, making me unable to count properly.
Thanks for your help.
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I would like to suggest to do it 12- or even 6 well plate to get attached monolayer. After infection, incubate the plate for 1 hr, take out the solution carefully with tips without touching the bottom surface. Add respective medium with 5% FCS and incubate 48-72 hrs to get nice plaque. for details you may check the following article; https://www.nature.com/articles/s41598-019-44220-4
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Hi all,
I wonder if anyone know where I can find the plasmid map for pHH21 that is commonly used in Influenza research?
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Hello Dat Nguyen
Please refer to the link below.
I hope this helps.
Best.
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Should we give steroids in every covid-19 patient with elevated inflammatory markers?
Can we demarcate between appropriate immune response and dysregulated immune response?
Does the answer lie in Interleukin-10 (IL-10)?
Dr. Prashant R. Wankhade
Hypothesis: Interleukin 10 (IL-10) is a potent anti-inflammatory cytokine which can guide regarding optimal use of steroids and immunosuppressants, allowing immune system to fight at its best.
Recovery trial has shown positive effects of steroids in COVID-19 patients who were receiving either invasive mechanical ventilation or oxygen alone but not among those receiving no respiratory support1.
Now-a-days steroids are among most widely used drugs in COVID pneumonia and we know that ‘steroid’ is a double-edged sword. If these drugs are given when patient is actually going through cytokine storm phase then it has beneficial effect but if we are administering them in appropriate immune response then it may be hazardous as it can cause suppression of immunity which in turn can escalate viral replication and subsequent disease progression.
Cytokine storm?
There is no widely accepted definition of cytokine storm.
Cytokine storm is an umbrella term encompassing several disorders of immune dysregulation characterized by constitutional symptoms, systemic inflammation, and multiorgan dysfunction that can lead to multiorgan failure if inadequately treated2.
IL-1, IL-6, ferritin, CRP are the part and partial of immune response irrespective of appropriate or dys-regulated.
Elevation of interleukin 6 and CRP is a part of cytokine storm but it’s not the absolute marker. We need to corelate these markers with overall clinical scenario to label it as cytokine storm.
So, which is the crucial moment to start steroid?
Does the answer lie in interleukin 10 (IL-10)?
Justification for the hypothesis:
Interleukin 10 (IL-10) is a potent anti-inflammatory cytokine that plays a central role in limiting host immune response to pathogens, thereby preventing damage to the host and maintaining normal tissue homeostasis. It is also essential for regulation of immune responses3.
The generation of an effective immune response along with limiting tissue damage requires a delicate balance between pro- and anti-inflammatory responses3.
Impaired IL-10 expression and/or signaling can enhance clearance of pathogens during an acute infection, but also exaggerate inflammatory response, resulting in exacerbated tissue damage4.
Some pathogens can harness the immunosuppressive capacity of IL-10 to limit host immune response, resulting in persistent infection5.
Though absence of IL-10 is often initially beneficial, it’s prolonged deficiency can be detrimental in the long term. Prolonged and increased production of inflammatory cytokines can lead to septic shock in the context of viral, bacterial, or fungal infections6,7.
Inflammatory molecules can often be potent activators of cell death and increasing levels of IL-10 can moderate the extent of apoptosis that is induced in response to infection.
For instance,
1. In a Chlamydia pneumoniae model, where bacterial clearance is enhanced in the absence of IL-10, mice also develop severe inflammation and experience elevated levels of apoptosis3.
2. During Mycobacterium avium infection, early IL-10 production is correlated with the failure of control of infection; ablation of IL-10 signaling led to enhanced pathogen control, demonstrating a causal relationship between IL-10 and the lack of pathogen control8.
3. In acute influenza infection, blocking the action of IL-10 results in enhanced pulmonary inflammation and harmful injury9.
It is not clear whether elevated IL-10 levels during infections are a cause or a consequence of high pathogen burdens, but studies indicate that resolution of infection requires a coordinated response in which initial pro-inflammatory mechanisms clear the pathogen and are subsequently limited by IL-10 before pathology occurs3.
A unique feature of the COVID-19 cytokine storm is the dramatic elevation of interleukin 10 (IL-10) in severe/critically ill patients which has led to speculation that IL-10 might play a pathological role in COVID-19 disease progression10.
Possible conclusions:
1. If IL-10 levels are elevated along with IL-1, IL-6, CRP, ferritin etc.: This indicates that IL-10 is already trying to control the inflammation by acting as anti-inflammatory agent and in-turn might be helping virus to proliferate. If in such situation we are administering steroids to the patient which can further suppress immune response leading to further viral proliferation.
2. If IL-10 levels are suppressed along with elevated levels of IL-1, IL-6, CRP, ferritin etc: If patient is showing clinical symptoms and signs of cytokine storm then this is probably the best indicator of exaggerated inflammatory response and such patients are probably the best candidates to be benefited from steroids and immunosuppressants.
3. If IL-10 levels are normal along with elevated levels of IL-1, IL-6, CRP, ferritin etc: Use of steroids should be guided by clinical symptoms of signs of cytokine storm.
Needs to test the hypothesis.
References:
1. Lin WS, Emberson JR, Mafham M, Bell JL, Linsel L, Staplin N et al. Dexamethasone in Hospitalized Patients with Covid-19. N Engl J Med 2021;384:693-704. DOI: 10.1056/NEJMoa2021436
2. Fajgenbaum DC, June CH. Cytokine storm. N Engl J Med 2020;383:2255-73. DOI: 10.1056/NEJMra2026131.
3. Iyer SS, Cheng G. Role of Interleukin 10 Transcriptional Regulation in Inflammation and Autoimmune Disease. Crit Rev Immunol. 2012; 32(1): 23–63.
4. Li C, Corraliza I, Langhorne J. A defect in interleukin-10 leads to enhanced malarial disease in Plasmodium chabaudi chabaudi infection in mice. Infect Immun. 1999 Sep; 67(9):4435–42.
5. Brooks DG. Interleukin-10 determines viral clearance or persistence in vivo. Nature Med. 2006;12:1301–9.
6. Gazzinelli RT, Wysocka M, Hieny S, Scharton-Kersten T, Cheever A, Kühn R, Muller W, Trinchieri G, Sher A. In the absence of endogenous IL-10, mice acutely infected with Toxoplasma gondii succumb to a lethal immune response dependent on CD4+ T cells and accompanied by overproduction of IL-12, IFN-gamma and TNF-alpha. J Immunol. 1996 Jul 15; 157(2):798–805.
7. Li C, Corraliza I, Langhorne J. A Defect in inter-leukin-10 leads to enhanced malarial disease in Plasmodium chabaudi chabaudi infection in mice. Infection and Immunity. 1999; 67(9):4435–42.
8. Fiorentino DF, Bond MW, Mosmann TR. Two types of mouse T helper cell. IV. 32 clones secrete a factor that inhibits cytokine production by 31 clones. J Exp Med. 1989; 170:2081–95.
9. Sun J, Cardani A, Sharma AK, Laubach VE, Jack RS, Müller W, Braciale TJ. Autocrine regulation of pulmonary inflammation by effector T-cell derived IL-10 during infection with respiratory syncytial virus. PLoS Pathog. 2011 Aug.7(8):e1002173.
10. Lu L, Zhang H, Dauphars DJ, He YW. A Potential Role of Interleukin 10 in COVID-19 Pathogenesis. Trends in Immunology, January 2021, Vol. 42, No. 1.
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Dexmethasone 6mg for six days or until hospital discharge is recommended for patients require supplemental oxygen. However, it is not recommended for patients that not require oxygen treatment.
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Croup is a viral infection affecting the upper respiratory tract. Its causative organisms includes Influenza and Parainfluenza viruses. This question aims to know the role of antiviral agents in the management of disease.
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there is no antiviral role in treatment of croup
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The Spanish flu, also known as the 1918 influenza pandemic, was an unusually deadly influenza pandemic caused by the H1N1 influenza A virus. Lasting from February 1918 to April 1920, it infected 500 million people – about a third of the world's population at the time – in four successive waves. Deaths: 17–100 million (estimates)
One hundred years later - 2019 COVID-19 pandemic.137 million cases, 2 million 960 thousands deaths.
The Spanish flu started on hundred years ago and continued for two years. Had four waves.
The COVID-19 started 2019 and continued for now. Had two waves, but pandemic continues.
Can we expect third and forth wave of COVID-19 in shorth time future?
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YES I AGREE
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Hi, I am looking for a test lab that can do tests on anti-viral activity of formulations. Strains to be tested are HSV-1, and for other formulation typically HRV, Influenza, and covid-19.
test labs may be from the west, say US, EU, but also from India, China, indonesia.
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There are two Anti_viral tests known for screening :1_Microneutrilization test(MN).2_Virus neutralization assay(VN).
These tests used to determine the presence of functional antibodies to prevent viral infection,where dilution of antibody sample(either purified antibodies or animal serum samples) are prepared in test tubes.Thanks
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We used to do the H1N1 WSN plaque assay without TPCK-trypsin, and it works fine. Now we are trying the H1N1 PR8 and H3N1 plaque assay, but the PR8 failed to form plaques, and the plaques of H3N1 was tiny and not clear.
I'm following the Virapur protocol, using DMEM and MDCK cells and my virus does make strong CPE effect in MDCK so I was wondering if adding TPCK-trypsin can optimised the result?
thank for the response 
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Luciana Tavares Are you using the same culture of MDCK or have you tried starting a fresh culture? I ran into a hiccup with mine because my cells weren't taking to the infection because they were old. (They looked fine, grew fine, but wouldn't infect!)
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Viral infections are unfortunately very common all over the world, and at least one type is experienced by most of us over our lifetime: influenza. Other well-known viruses include chicken pox, herpes, HIV (human immunodeficiency virus), and mumps. These kinds of conditions caused by viruses are different from bacterial infections in that viruses have an external wall (known as the viral envelope), which is nearly identical to that of the cells in the body in which they exist. This makes it difficult for them to be isolated and targeted by medication.
Viral infections can be combated by vaccinations and some prescribed drugs. Alternatively, the following antiviral herbs can help with the symptoms.
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Dear all,
I have a naive question. When we want to study Type 1 response, we infect mice with influenza for instance, if we want to study Type 2 response we use for instance T. Bruecei. Does anybody know which type of response we induce when we immunize with our classical protocols such as SRBC or NPCGG/NPOVA/NPKLH?
Thank you very much
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From an old hand at immunology, a Type 1 response is what we used to call a T-dependent antibody response, and that is triggered by viruses, SRBC and hapten-carrier conjugate. Basically, the B lymphocyte binds the relevant antigen [in your case, NP], endocytoses it and processes the carrier protein for display on its' surface class II MHC molecules. If a T helper cell recognizes the carrier protein antigen that is displayed, it binds to the B lymphocyte and stimulates it to produce antibody. For naive B lymphocytes, you get IgM initially, but IgG later in the response. Classic immunology.
Type 2 responses are T-independent; the carrier is LPS, or Ficoll or T bruecei. These are or have repetitive structures that bind to the B lymphocyte and crosslink the surface immunoglobulin [IIRC, you need a complex of at least 10 hapens to trigger the response and Toll-like receptors are involved]. For T-independent responses, you get primarily IgM, and some IgG3 in mice.
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As widely accepted presently, early childhood education and development are closely intertwined and Impossible to truly set apart. Adults, living in pandemic Times, are pivotal actors in the way this challenging Times integrate children's development.
Educators, parents, political leaders and other stakeholders how should we go about this to assure the best developmental outcomes for the new generation ranging from 2 to 6 year old, within this important frame of socialization and development stages? Should we look to what happened during the great influenza for lessons?
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I think we should take away some lessons from the great influenza. however, we do have more resources to provide children with appropriate support that they need now.
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Previous research has suggested an involvement of meteorological conditions in the spread of droplet-mediated viral diseases, such as influenza. However, as for the recent novel coronavirus, few studies have discussed systematically about the role of daily weather in the epidemic transmission of the virus.
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With the appearance of COVID-19 vaccines on the market, many available choices are there.
Which one is good?
Which one is safest?
Which one is most expensive?
Which one is easiest to store?
How many doses are required?
Other than intramuscular injection, any other forms?
How to check immune response after?
Do we need post-injection blood test?
Do we need annual booster dose?
Do we need new vaccines every year by prediction as if flu vaccines?
Any contraindications?
Any allergy from vaccination?
Do we need to mask after injection?
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Agreed with dear Arvind Singh
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Hello,
Most hand sanitizers contain 60-80% alcohol. Alcohol destroys organisms including bacteria, fungi, protists, and enveloped viruses by breaking down the plasma membrane. In recent years, microbial communities on the skin, in the airways, and in the gut have been shown to play an important role in health. Does daily use of hand sanitizer negatively impact the diversity and strength of the hand microbiome? If so, what are the implications of this to overall health? Do skin microbes play beneficial roles such as helping to prevent transmission of other pathogens?
Thank you.
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All literature data I came across showed that Ribavirin had equal if not greater effect in titer reduction, survivability, and body weight loss compared to Oseltamivir. The biggest difference I found was that Ribavirin caused lower levels of interleukins but I'm not sure if that correlates to that rarity of its practical usage.
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doi: 10.1007/s13238-016-0287-0
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Can the formation of drugs against coronavirus also be useful against the Influenzas virus or HIV? This is because these viruses shared many common proteases for viral replication.
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Dear Talha Bin Emran, the answer is no, the targets and the mechanisms of action aren't the same. My Regards
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Kindly share any research outcomes related to the above topic or virus /influenza based on the contemporary situation.
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Fareena Ruzaik Your question is valid and worth further study. To penetrate the ground water supply, you need to take into account soil sorption and microbial degradation/predation as well as depth of soils. A more immediate concern is water runoffs from heavy downpour or in unexpected cases flood (especially in this monsoon season for tropical countries).The decaying covid-19 bodies would be a huge source of the virus and if the water runoffs from mass graves for example Iran or Brazil would be significant as these waters can contaminate the source of water supply for human or animals and the latter can become future reservoir (think mink).
see
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Antibiotic resistance and the emergence of many new viral strains due to climate change, animal farming and deforestation are increasing the usefulness of pharmaceutical agents, incl. antibiotics. We are currently dealing with yet another viral pandemic. Are there any natural plant extracts that are being studied that are effective disinfectants for the whole suite of fungal, viral and bacterial infections that act as pathogens to humans ? Particularly interested in those effective against coronaviridae ?
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Or not?
In The Great Influenza by John Barry at p. 340, about government controlling fear, writes: "They could not control it because every true report had been diluted with lies." At page 460, he writes: "For if there is a single dominant lesson from 1918, it's that governments need to tell the truth in a crisis. Risk communication implies managing the truth. You don't manage the truth. You tell the truth."
An article touching on these issues is, The Only People Panicking Are the People in Charge, by Malka Older, September 16, 2020.
Statistics, lies and the virus: Tim Harford's five lessons from a pandemic, Sep 10, 2020 Financial Times magazine, includes: "Carefully gathering the data we need, analysing it openly and truthfully, ... this is the only chance we have to defeat the virus ...."
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Yes..
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I have done 3 blind passages to concentrate the viral stock in the supernatant without adding TPCK Trypsin. After passage 1 my Ct value for INF A was 36.96. After P2 the value decreased to 33.36. However, I was expecting a much lower value in the mid-20s. I am freeze-thawing the flasks at -20 degrees to lyse the cells and release the virus into the medium. Is it the correct approach? and can I get a much higher titre without adding TPCK Trypsin?
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thanks for the suggestion. I too thought that DI particles are interfering with the formation of whole virions but i am skeptical that will diluting actually work.
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I am looking for your opine
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As the clinical syndromes associated with SARS-CoV-2 and influenza are broadly similar it will be difficult to distinguish these infections in winter when the seasonal increase in influenza typically occurs.
However, social distancing measures should reduce the incidence of both influenza and COVID-19.
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I am looking for protocols and/or information as to how to perform sucrose gradient ultracentrifugation to purify samples of influenza A that have been propagated in egg allantoic fluid. Does anyone have any protocols that includes the speeds used? (Protocols that do not cause lysis of the virus after purification are greatly appreciated as well)
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Interesting question. Following the discussion.
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UVGI technology has long been known to be an effective tool to fight against airborne infectious viruses. However, lower wavelength UV light source (<240 nm) is also known to induce Ozone production from oxygen in the air. In addition, UV light is known to have carcinogenic and cataractogenic effects. UV lamps of wavelengths in far-UVC range (207 to 222 nm) and low dosage (2 mJ/sq.cm) have been studied to have an effective germicidal effect by neutralizing viruses and bacteria without adverse health effects to humans. Far UVC has emerged as a promising technology in the recent years ( https://www.nature.com/articles/s41598-018-21058-w ). While the use of wavelengths higher than 240 nm can be incorporated in enclosed systems like air purifiers and HVAC which can minimize direct skin and eye exposure of humans to UV light, far UVC has additional advantages of usability in open configuration in public places.
What are some other known real-life challenges and other important issues associated with UVGI technology to be cared for while designing systems integrating HEPA/ULPA filtration to be used in portable air purifiers, HVAC systems or upper room UVGI lamps in hospitals, commercial and residential buildings specially in the context of fighting the rapid spread of infectious viruses like the coronavirus associated with COVID-19?
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The following may have useful information
Deleted research item The research item mentioned here has been deleted
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Does anyone know of a panel of serum/plasma with antibodies to known pathogens such as Influenza A, HBV, HCB etc, that could be purchased for testing? or through ethics application to biobank?
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The NIBSC (https://www.nibsc.org/) has various antibody panels for different infectious diseases, but doubt there is a single collective panel for widely different pathogens.
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Does anyone know what the immunogenic similarities of the two mentioned viruses are (I mean the specialized similarities needed to make a vaccine, such as a specific genomic sequence)?Please give me more information.
Thanks.
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Inhalation of steam from the decoction of mint and oregano can be effective in treating lung infections and coughs caused by COVID-19 or influenza, especially during the recovery period. This has been explored in a very small statistical community.
These plants can act as inhaled antibiotics and can be applied directly to the infected areas, especially the inactive parts of the lungs, and can be effective in treating the infection.
These herbs also have anti-inflammatory properties and can be effective in treating cough and easier breathing of patients.
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In addition, these plants have a warm nature, while these viruses have a cold nature.
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The NS1 allows that patients asymptomatic can infect.
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There does not appear to be any such interaction between SARS-CoV-2 and host ACE-2 receptor to block the interferon system. In fact reverse is true.
To see why, have a look at the attached articles:
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Hi everyone,
We are synthesizing a virucidal material that will kill SARS-CoV-2 on contact.
In these preliminary stages, we want to use enveloped surrogate viruses that are the easiest to propagate and safe to handle. For example, Phi6 bacteriophage and its easily cultured host, Pseudomonas syringae.
Other CoVs (299e, OC43, etc.) and influenzas have been considered, but as I said for now we want to keep complications to a minimum.
Any advice on possible enveloped viruses to use?
Thanks,
Max Bueckert
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follow
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COVID-19 is a worldwide threat to humanity and spread fast. There is no effective vaccine yet, the combined antiviral therapies are performed and have a higher success rate. But we need additional treatments and approaches to this disease.1
I and my colleague realized that the levels of high-density lipoprotein (HDL) and non-HDL were very important for sepsis fatality in a small observational study. We tried to predict mortality with lipoprotein levels and ratios. We have believed that there is a balance between HDL and non-HDL, and it is an immunological actor for infectious disease.2 Our study was about bacterial infections, but a similar relationship may exist in viral infections. Hepatitis-C infections may alter lipoprotein metabolism. Statins have used for adjuvant treatment for chronic hepatitis-C infections.3 HDL may be an innate immunity actor, modulate macrophage functions and inhibit thrombotic events. LDL decrease was shown with inflammation.4
A meta-analysis showed that total cholesterol and low-density lipoprotein (LDL) levels were good predictors for Dengue virus severity. The investigators thought the lipoprotein levels should be screened routinely and the approach should be reconsidered with these levels.5
Another study showed that statin users with Influenza had fewer complications and 30-day mortality than non-users. But this protective association was demonstrated for some seasons and subtypes.6
The lipoprotein levels and ratios may be explored in COVID-19 screening and follow-up may be a predictor for prognosis. These levels and ratios may be targets for treatment.
References
1. Yan Y, Shin WI, Pang YX et al. The First 75 Days of Novel Coronavirus (SARS-CoV-2) Outbreak: Recent Advances, Prevention, and Treatment. Int J Environ Res Public Health. 2020 Mar 30;17(7). pii: E2323. doi: 10.3390/ijerph17072323.
2. Karahan I, Cifci A. Are Lipoprotein Levels and Ratios Able to Predict Mortality due to Sepsis? J Coll Physicians Surg Pak. 2020;30:272-275. doi: 10.29271/jcpsp.2020.03.272.
3. Aizawa Y, Seki N, Nagano T, Abe H. Chronic hepatitis C virus infection and lipoprotein metabolism. World J Gastroenterol. 2015;21:10299-313. doi: 10.3748/wjg.v21.i36.10299.
4. Levine DM, Parker TS, Donnelly TM, Walsh A, Rubin AL. In vivo protection against endotoxin by plasma high density lipoprotein. Proc Natl Acad Sci USA 1993; 90:12040-4.
5. Lima WG, Souza NA, Fernandes SOA, Cardoso VN, Godói IP. Serum lipid profile as a predictor of dengue severity: A systematic review and meta-analysis.
Rev Med Virol. 2019;29:e2056. doi: 10.1002/rmv.2056. Epub 2019 Jun 6.
6. Atamna A, Babitch T, Bracha M Statins and outcomes of hospitalized patients with laboratory-confirmed 2017-2018 influenza. Eur J Clin Microbiol Infect Dis. 2019;38:2341-2348. doi: 10.1007/s10096-019-03684-y.
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As a LT statin-using patient, I am selfishly interested in this research. Best of luck!
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JAMA article published today states that SARSCOV2 is at least 40 times as deadly as the Influenza virus. Why are most people not concerned? Do they not know this information? Do they think that they are immune? Do they not trust the Health authorities? Do they know that the data, assumptions made, results and conclusions are somewhat suspect of comparing "apples to oranges?" Do they not see evidence to support the studies? I went out today, it seems like I was the only person taking precautions. Why?
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July 24, 2020: As shown by CT Scan that 97% of people who are positive for COVID-19 by RT-PCR developed pneumonia; in the following study:
Hope, MD, Raptis, CA, et al: A Role for CT in COVID 19? What data really tells us so far. Lancet 2020: 395; 1189-1190.
So, almost invariably, anyone positive for the virus by PCR will have "pneumonia" by CT Scan of the chest, and thus some degree of pulmonary injury, loss of function, lung scarring, and perhaps metaplasia formation. This was even present in non-clinical and sub-clinical cases. More evidence that one should not promote "herd-immunity" before the vaccine is given. Stay safe, thank you; Gary Ordog, MD
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Due to their small size, viruses were shown to dry and die quickly, especially on porous (hydrophobic) surfaces and in dry environments.
Could drying the air be a method of treatment / prevention for colds and influenza?
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Definitely sunlight has a disinfection effect, as shown in studies using artificial ultraviolet light. The problem with solar or artificial radiation is that it propagates only in straight line, thus it does not reach the shadowed areas.
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In this review I will elabotely study the complete spectrum of antiviral compounds used in different Viral Diseses - applied to the latest Covid19 Pandemic .The review is mainly based on to point out the Older to Newer antiviral medicine -from Medicinal Synthetic background .
Your openion will be cordially welcome - Thanks
Jaydip Datta
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But earlier anti-viral medicine is Amantadine.hydrochloride - from where we have started the anti-viral synthesis . It is antiviral ,antiparkinson as well as antiallergic
compound .
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I am interested in measuring the underlying inflammation associated with viral infections (corona virus or influenza) to test the hypothesis that a inflammation-associated severity index might have clinical utility in treating patients. The prototype can be seen at: https://cslide-us.ctimeetingtech.com/actrims/attendee/eposter/poster/66
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Good topic
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Is the absence of decision by UK and NL to enforce social distanciation against Covid19 (unlike China, Italy, France, Spain, Germany, USA, etc) caused by memory loss of the positive effects of proactive enforcement of social distancing by US cities in the 1918 influenza pandemic? Death rates were reduced by 50%, source:
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Many thanks to all contributors. What emerges is that although the viruses of 1918 and 2019 are different, human behaviours in these two pandemics can be compared. Is it not notable that the portfolio of NPIs (non pharmaceutical interventions) is the same: handwash and reinforced hygiene, self-isolation, quarantine, lock-down, social distancing, gloves, face-masks?
100 years for not inventing better, and not learning from 1918 or from other countries (China/Wuhan) how to detect and implement early?
100 years to forget!
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Which markers are suitable for assessing the effect of influenza on the heart (FABP or NTproBNP, ELISA)?
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What about troponin?
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The 1918 H1N1 Pandemic Influenza did not have a vaccine. In fact, physicians and scientists didn’t even know what a virus was or how it worked. They knew it was not bacteria and that it did not seem to be alive, but that was about it. But for the transmission, most scientists thought it was a chemical agent of some sort.
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There was no vaccines for the Spanish flu of 1918. It ended in the summer of 1919, mostly due to deaths and higher immunity levels.
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Given the scale of this pandemic, it is possible that 2020 is just the first (and worst) year of an annual coronavirus outbreak, similar to how we have an annual flu season.
Coronavirus mutates at a faster rate than influenza (Nextstrain was researching flu when the pandemic started and they are currently tracking mutations in SARS-CoV-2 too). By the time billions of people have been infected, SARS-CoV-2 (the novel coronavirus) may have mutated into a few distinct strains, different enough to each require its own vaccine.
It is also possible that a strain appears that is far less lethal. If this disease was killing 1 in 10,000 instead of 1–5 in 100, we probably wouldn’t even have noticed it until tens of millions had been infected and we’d probably just let it run its course without any actions, just as we do every year with the other coronaviruses that cause the common cold.
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This is a difficult question. In principle, a pathogen can be eradicated if humans are the only hosts. This was the case with smallpocks, which were successfully eradicated in the 1970ies through vaccination campaigns organized by WHO. SARS-CoV-2, however, has apparently intermediate animal hosts or even bats as the primary source. It is impossible to control the huge bat population. In consequence, we have to wait for the vaccination and carefully study how long immunity is provided through vaccination(s) and, possibly re-vaccinate after a given period of time (as is the case with the influenza vaccine). Fortunately, mutations occur at a lower rate in SARS-CoV-2 than in influenza viruses.
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As we know, Australian researchers have found that body's immune response to COVID-19 is similar to influenza. Now my question is: "Does getting influenza give some immunity against COVID-19?"
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No, different virus altogether. Chances of cross immunity would be exceedingly small as the protein structures the immune system would have stored to react to would not match the coronavirus
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I am interested in the robustness of this technique. I have seen so far publications only from the lab of founders of the technology. Therefore, my curiosity if it is used in the field of vaccine development too
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I have not personally used the VaxArray technology and have not reviewed it thoroughly. For measuring potency of influenza vaccines using HA antigen, you need to make sure that VaxArray measures antigenicity of HA that is measured by SRID (HA trimer). You may also like to speak with the regulatory agencies about their experience with VaxArray and whether VaxArray technology would be acceptable as an alternative to the SRID potency method. I am sure that if the scientific basis of VaxArray technology to measure HA antigen is same or similar as the SRID and there is data to show that the VaxArray measures the HA trimer, the regulatory agencies would accept the VaxArray technology. Of course, you would need to generate appropriate method validation and comparability data between VaxArray method and SRID. Alternatively, if the the VaxArray method and SRID method do not measure same form of HA antigen and there is no correlation between these methods, you need to demonstrate the the VaxArray potency method is a surrogate for clinical effectiveness of the influenza vaccine. Best wishes.
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Referring to research papers and general advice are welcomed as part of the discussion
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Zeyad T. Al-Rrassam Yuan-Yeu Yau many thanks for participating in this disuccsion.
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Which markers are suitable for assessing the effect of influenza on the heart (FABP or NTproBNP, ELISA)?
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Which markers are suitable for assessing the effect of influenza on the heart (FABP or NTproBNP, ELISA)
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Can either rhinovirus or Dengue virus, for instance, coexist with coronavirus in the same infect cell?
It is know that multiple viruses can coexist in the organism, like HIV and C hepatitis, B and C hepatitis, syncytial respiratory and influenza viruses, Dengue and Chikungunya viruses, etc.
SARS-Cov, SARS-Cov-2, rhinovirus, Dengue virus, among others viruses, are Group IV RNA viruses that affect the respiratory tract, and could target to some extent the same epithelial cells. Peace and blessings.
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I am no expert in that area, but my guess is that Dengue, Zika and other flaviviruses don't really go for lung cells so much. I have never seen much research or speculation on dual infections with influenza plus Dengue, or common cold coronavirus plus some other virus. HIV plus HCV is not good, and has been researched a lot. HIV plus tuberculosis is not good. I suspect that dual infections in general are more additive than synergistic, but it would not matter much if the pathogens are in the same cell, so much as that they are in the same host body and the immune system can only fight so much at once.
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We want to study about influenza viruses and producing vaccines. In vaccines, 15 mcg HA / 0.5 ml units are determined for each strain. Which methods are used to calculate this concentration? I am glad if you give me information.
Thank you for any advice.
Regards,
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The potency of inactivated influenza vaccines is determined by the single radial immunodiffusion (SRID) method against monovalent antigen standards and HA specific antibodies obtained from National Control Laboratories (NCL), including US FDA, UK's NIBSC, Australia's TGA and Japanese NIID. These 4 NCLs collaborate to harmonize the strength of standard antigens. Monovalent bulk pools are tested for SRID potency by multiple tests to get the HA antigen content of pools in terms of µg/ml, as determined by SRID. Based on that value the DS or quadrivalent vaccine is formulated to contain 15 µg of HA per dose of 0.5 ml. The DP is finally tested for potency by SRID to confirm the potency and release the DP.
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1918 influenza pandemic caused death more than that of combined death in World war I & II. Since then world has faced four Influenza pandemics. last one in 2009. We are in threat of more Influenza pandemics. What measures could be taken to prevent the development of Influenza pandemics?
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Its quiet difficult to predict influenza pandemic due to continuous antigenic shift which is occurring in this virus.
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I am doing a research on the social aspects of digital epidemiology by using a case study methodology on influenza. The literature from PubMed and Springer on digital epidemiology indicate the use of Google Flu Trends (GFT), Google Trends (or other research engines on Internet) and digital data from mobile devices. So my question is this one: is there always artificial intelligence when using these technologies in the context of research in digital epidemiology? The goal of this question is to determine if artificial intelligence will be included as one of the aspects of the definition of digital epidemiology in the context of my project. Thank you very much.
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Hello, thank you very much for responding
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Sure, quite well (e.g. see Oncol Rep. 2013 Jul;30(1):462-70. doi: 10.3892/or.2013.2413.)
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Hey there,
I've been trying to purify these influenza samples, however, I've come across 2 problems. I've repeated the procedures twice and have come across the same issues both times (first time thinking some error had occurred).
Sample 1: After PCR, product is visualised on gel to see if there is a correct product size. There is but also some non specifics, so I cut the band out. After gel purification, the band is now larger bp than original. Size of PCR product is 916bp. However, after purification, it is now well above 1000 bp.
Sample 2: After gel purification, the product has disappeared.
I know it is not an error of the kits (i.e forgetting to add ethanol to wash buffer or forgetting to incubate) as I have used these same kits to purify many samples before it. So these are perhaps sample-specific problems.
I have run these samples using both the Qiagen Gel Purification kit and the Intron Purification kit. Both times have encountered the same problem.
Any recommendations on what I should try?
Thank you so much!
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If you use the Qiagen Gel Purification kit it really helps when you warm the Elution buffer up to 37 degree. But this just help to increase the yield of eluted DNA.
For the first question did you use the gel with the same percentage of agarose and the same marker from the same company?
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Hello everyone;
I'm preparing my master thesis it's about influenza prediction using deep learning. The data that I had is the rate of dangerous cases and the suspicious ones per week and per region around the country.
for now I implemented the Random Forest, KNN, DNN, LSTM, CNN, CNN-LSTM and Deep Belife Network. I concluded that I'm faced with time series forecasting so I used the window method to make my problem surpervised with window_size=3, 2 and 1. Calculating the r2_score I got 10 regions under the 70% (which I had read that it's the acceptable threshold).
So I'm writing this question hoping to find a solution or get some idea or another deep learning technique and maybe special architecture of the technique used above to improve my prediction in this region.
and thank you in advance
(You will found attached some picture of the regions that I want to improve and my LSTM model.)
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Spatial autoregressive models are statistical models A good paper is : ``About predictions in spatial autoregressive models: Optimal and almost optimal strategies’’.
The following link for the R codes used to obtain the simulation results included in this paper :
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These are not contaminants. I have checked several times. I have used Gibco high glucose DMEM media with 10% Heat inactivated FBS and 1X anti-anti. I have used gibco TrypLE for trypsinization for around 10 mins. I do not understand what it is?
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Since you have ruled out the contamination or mycoplasma infection, you can try to replace the high-glucose/DMEM by MEM/NCS 5%.
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Interested in bio security aspect of disposing of horse faeces in an Equine Influenza 2 outbreak. Cannot find any research regarding if the virus is or is not shed in droppings. Also, how long would the virus remain infectious in the bedding?
Many thanks
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Many thanks, Kelli, this is very relevant and helpful. Kind regards Janine
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Canine influenza viruses (CIV) are contagious respiratory diseases found in dogs. These Type A influenza viruses and the H3N2 (canine and human) virus is known to infect dogs, cats and people. There is a concern that the disease can mutate with dogs being the ”mixing bowl” and potentially produce a pandemic. See: https://www.ingentaconnect.com/search/article?option2=author&value2=Daesub+song&pageSize=10&index=1#
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Most recent publication (April 2019) of Daesub Song and collaborators. See: https://acmi.microbiologyResearch.org
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I am attempting to perform a qPCR standard curve using viral DNA (Adenovirus and MCMV) and cDNA (Influenza A) to be used to determine relative abundance of these viruses in primary samples. Viral DNA and RNA was extracted from viral stock using the QIAmp MinElute Virus Spink kit and vRNA was converted to cDNA using the ImPromII Reverse Transcription System. 6 point 10x dilutions were performed using this viral DNA and cDNA (undiluted-1:100,000) and a negative water control was included. For the qPCR, I am using TaqMan Universal qPCR Master Mix along with virus specific primers (forward and reverse) and probes whose sequences were provided from literature review or provided by neighboring labs but have not previously been used by our lab with this particular master mix. I believe that all of the input DNA/cDNA concentrations are fine (ranging from 17-180 ng/rxn note: master mix prefers concentrations <250 ng) and being that I have repeated these experiments a number of times with great care, I do not believe that it was a pipetting error with the dilutions. The amplifications curves, especially for Adenovirus, do not follow the natural curve progression seen in most standard curves and for all of the viruses the points do not fall on the slope of the standard curve line. I have attached photos for reference. I have tried repeating these experiments many times and adjusting the input concentrations of the viral DNA and cDNA. All experiments were for each virus was done separately, there was no multiplexing. I am wondering if it is possible that the primer efficiency may be the problem. The annealing temperatures for these primers are slightly higher (~3-6 degrees) than recommended by the master mix but a representative from Fisher seemed to believe that the reaction should still work. Also the target regions for these primers seem very short (all <150nt). Is it possible that I need to design new primers or is there possibly another obvious issue. If anyone could provide any feedback on what they believe the possible problem is or has further questions, please let me know.
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Did you try to quantify your cDNA? Ferralita Madere
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I m using dh5 alpha cells to insert some specific segments from influenza A . I ligated the cells using TA cloning kit and transform them . I cultivated the cells on an LB media with ampicilin , Xgal and IPTG for the blue white screening. The screening worked perfectly , I cultivated them overnight and after this I used the Qiagen mini prep kit. I used ecor1 to digest the mini prep and after this i run a gel electrophoresis (agrose at 1%) for 45 minutes at 70V . I can't understand why I got the top bands like this , is it super coiled DNA ? Is something normal or I didn't do any of the steps properly . Does somebody know where I failed ?
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Hi Sandu,
First please consider the bellow suggestions:
1. Dilute your digestion samples and also your ladder
2. Let your gel electrophoresis run further so bands separate completely
3. Increase the voltage to 90-100
4. Digest your self-ligated plasmid (without an insert)
5. Load undigested plasmid (harboring insert) as control
What is your plasmid and insert size? Do you have your expected insert released in the current gel?
How long did you treat your recombinant plasmid with restriction enzyme (s)? did you digest it with a single enzyme or two? How many sites are there on the plasmid for enzyme (s) used? Are all the lanes representing the same insert and plasmid?
After successful digestion you have two bands including your linearized plasmid and insert, and if your cloning is not successful then you only see a single band on gel. In case you see other band patterns varying between the lanes would be due to unsuccessful digestion which might be due to short digestion time or missing of any other factors required for digestion.
Further, white colonies could be tricky and not really containing the desired fragments; if this is the case you do not see your insert band after digestion … performing colony PCR before digestion can help you to verify the ligation as well.
I think you have to prolong your digestion reaction to let it have a complete cut and also to check out if other required factors such as temperature, DNA/enzyme concentration etc. are set to optimum.
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Hello,
I was doing a PCR for influenza viruses ( more specifically defective interfering segments) and i had good results beside 2 segments. I store them at -20 degrees and i was thinking to run them 5 cycles more ( initially all the sample were run for 15 cycles) . Do i need to make fresh samples or i can just reuse the 2 stored samples. I'm thinking just to place them in the PCR machine and add 5 more cycles to this 2 samples .
Will this work ?
I know the buffer, dNTPs , Taq polymerase and others are limited and have a specific life expectancy of PCR cycles, but 20 ( 15 already done + 5 which i will run )cycles from my presumption will not exhaust all the dNTPs and other reagents.
Thanks a lot ! Sorry for this stupid question !
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That likely refers to the concentrated stock, usually in 50% glycerol (so it doesn't freeze even at -20): enzymes last longer at cold temperatures, provided they don't actually freeze solid (ice crystals can do bad things to proteins).
Once you've diluted your Taq to make your PCR reaction mix up, it will freeze solid, and this will usually result in a stark drop in viability.
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Hi,
I want to see if my mice have gotten infected, is it possible to coat an ELISA plate with IAV broken up by sonication?
Thank you!
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In case anyone else is wondering if it works, I tried it today and it works!
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Hi, I want a correct protocol for plaque assay with influenza viruses .
I used MDCK CELLS ( 450 000 cell/well ) with different strains and different plates but i didn't see plaque formation but only holes on all conditions ( also control).
What do you think about this problem?
Can i have a correct protocol of it?
thank you
best regards
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Camilla, from your protocol that you sent, you did not add TPCK-trypsin, which is required for your virus in order to visualize plaques. You should use 1 - 2 ug/ml TPCK-trypsin to your cultures. This should allow you to see nice plaques withing 2-3 days.
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Vitamin D status is associated with upper respiratory tract infection and / or influenza.
Of course such association (or causal relation) is stronger when there is :
- initially state of deficiency (lower than 50 nmol/L or 20 mg/nl)
- sufficient high dose of suppletion (e.g. 1000 - 2000 iU / d)
- time of suppletion is long enough (at least 3 month) before the season of cold / influenza etc starts
I point at a metaanalysis of Martineau et al (BMJ 2017) and know of some special RCT's but I would like to discuss this with you and maybe find some extra evidence regarding a positive association / causal relation.
Martineau Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data
BMJ 2017;356:i6583 | doi: 10.1136/bmj.i6583
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Poultry diseases cause increased mortality and high economic losses. Is it possible to breed to produce disease-resistant poultry strains?
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It would be very long and expensive, but not impossible. To achieve this, chicken breeds with a high genetic variability would be required, since many of the current breeds have been improved for productive characteristics, which has caused that the current chickens are more susceptible to some diseases, which has caused a low heritability of the characteristics related to resistance to diseases. Therefore, it is necessary to increase the genetic variability to obtain individuals with high genetic heritability to specific diseases.
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How to seek for the UTR of IAV?
Is there any database to seek for the UTR of influenza?
I need to know the UTR sequence of influenza to rescue IAV.
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You can RACE the UTR sequences or use universal primers (Hoffmann E et al.) for reverse genetics.
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I was using MDCK cells to grow Influenza H1N1 in 12-wells plates. Cells was seeded 1 x 10^6 cells/well and left overnight in media without serum. Cells were then infected with H1N1 at moi of 0.1 and virus titre was tested by HA assay after 24 hrs, and 48 hrs.
Trypsin was added during infection.
Under the microscope, the cells was achieved ~80% cytopathic effect after 48 hours. However, no titre was determined by HA assay (all negative HA) either after 24 hours or 48 hours.
Is there any mistake happening here?
In my point of view, first, I guess its because of the temperature during harvesting, virus was harvested at room temperature from 37C cell culture and spin at 4C and then store at -80C freezer for further HA testing.
Second point, was the virus titre too low? or was the cells density too low?
Does anyone here working in the same field or experiment with me before?
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What strain of H1N1 and what species of RBCs? Not all flu strains have the right sialic acid preference for a given type of RBC. Also, the HA assay is probably the least sensitive routine titration method for flu. If you used an infectivity-based assay you might find you have some replication.
paul
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I'm currently performing the MN assay using A/Hong Kong/4801/2014 (H3N2) strain of influenza. I came across a strange change in cell layer post 3 days of inoculation with the virus. The cells were detached from the surface of the well and formed clumps. Surprisingly, the clumps are found around the corners, so it has generated half-moon shape in the well where half of the cells are attached smoothly and rest half are detached and clumped.
I seeded cells 2 days ago and then used the plates for the assay.
Thank you in advance.
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Hi Aakash, How was your negative control? Did the cells also form a moon-shape like your sample well and positive well? If the negative wells are doing the same thing, there might be something wrong with your culture. Have you checked the supernatant in day 3, was it too low to cover the surface of the cells? Did the half moon-shape in all wells appear in the same side (all left or all right side)? If yes, maybe the place you incubate the plate was not horizontal, you can check using a gradienter. Hope it will be helpful.