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Hello;
I'm trying to review the current situation of schistosomiasis in Equatorial Guinea and only find papers describing cases due S. intercalatum. I think it's a little strange that  S. mansoni or S. haematobium are not reported. Does anyone know the epidemiological situation of esquistosomisis in Equatorial Guinea? Do you know where can I find literature?
Thanks
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schistosomiasis is considered as a major parasite and prevalent parasitic infections, affecting an estimated 200 million people infected, mostly in Africa. Equatorial guinea is a country located on the west coast of central africa, where schistosoma spp. is endemic. Human schistosomiasiscin equatorial guinea is caused by Schistosoma intercalatum. In studies conducted in Bata, mollusc species could serve as a potential host for schistosomiasis was found in Bulinus forskalii. The prevalence of the disease is higher in the city of Bata than in rural areas.
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In the last few months I observed some acute leukemias associated with positive malaria or with history of recurrent malaria manifestations.
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How the malaria parasite increases the risk of blood cancer
in this link;
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I am working on a research to determine the endemicity classes of different regions in a country which means that each region has to have one endemicity class. I am looking for ways of using different classes for each region to come up with my results
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Thanks for all the tips! This was extremely helpful
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I am working on the effect of malaria parasitaemia on cardiac metabolism in adults, the parameters of interest include Lipid profile, Troponin1,Ck Mb, uric acid, Tibc and myoglobin
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Thanks for all the tips! This was extremely helpful
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I have some 2 drugs that I want to determine their nature of interaction against a tropical disease parasite. I need to plot an isobologram to achieve this. How do I go about doing this?
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Were you able to do this? Let me know if you have any questions.
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During the last years, Brazil has experienced epidemics by Dengue, Zika, Chikungunya and Yellow fever.
In Brazil has been an increased number of cases of mayaro fever in several Brazilian states and with the increased circulation of chikungunya virus, there is always a question about the ethiopathogenesis due the similarity of both virus (clinically and structural).
What do you think about it? Following some interesting articles.
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For usutuvirus there is a greater risk in North America by the vectors, however the spread could happen from North America to South America (in the opposite way that Chik and Zika)
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During off the season/winter season, what should be our best strategies for dengue vector control to prevent from next epidemic season? I think Integrated vector management (IVM) strategies should be used round the year. We should continuously use ovitraps to check for seasonal trends, increase or decrease in vector population so that timely use of conventional control methods could be applied. Ovicides like bleach and some botanical extracts might be beneficial. But kindly share your ideas and experiences?
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following
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what is updated management of Dengue fever?
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Check the following reference Please.. it might's assist you in your question …
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If so, how can I use PCR assay in detection of these strains in clinical samples?
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The resistance mechanism for imidocarb and diminazene are unknown.
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We do know that Zika virus is causing a pandemic problem that causes microcephaly on newborns. Now upon looking at several websites regarding zika virus, there are certain ways to stop the spread but also dangerous like using Ribavirin which inhibits the synthesis of viral RNA but small dosage can cause birth defects as well as to cause . Will there be a way to find out what other receptors or is there any other receptors it carry other than the E glycoprotein which also carries the function of cell to cell communication on this enveloped virus?
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Bloodstream trypomastigote is the nymphal stage of T. cruzi in mammals.
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How do you coat an antibody on a nitrocellulose membrane in order to develop immunology parasite antigens diagnostic strips?
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If someone have any idea if retroviruses (other than HIV) could be transmitted by mosquitoes, or if mosquitoes support retroviral replication.
Any papers/books etc..
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Thanks a lot Jana. I ve been looking for the paper for long. many many thanks.
regards,
SD
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Widal test seem to be the commonest laboratory investigative tool for Typhoid fever and the serology titre for significant result seems different from different laboratory setting  in endemic region,even possibly in non clinical subject , how can we measure the effectiveness of widal test for Typhoid fever where water supply is still a problem.  
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Though the negative test may not exclude typhoid, the positive test (titre of >1/160) will be useful in culture negative, or when blood or stool cultures are not practical, or in out-patient settings. In Sri Lanka, the country is considered endemic and often the disease is diagnosed with the suggestive clinical presentation. The disease is more prevalent in urban areas where culture facilities are usually available in tertiary care centers but the prior antibiotics render the cultures negative. I, though not often, still use widal to get a clue in difficult cases. Please read the following research as well; 
Trop Geogr Med. 1981 Dec;33(4):329-33, Diagnostic value of the Widal test, Abraham G, Teklu B, Gedebu M, Selassie GH, Azene G.
Clin Diagn Lab Immunol. 2002 Jul; 9(4): 938–941, Widal Test in Diagnosis of Typhoid Fever in Turkey, Ayse Willke,,* Onder Ergonu, and Banu Bayar
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A well person with with no active malaria ,Would they not be positive as well for Rapid Kit testing for Malaria in  endemics countries?
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Asymptomatic parasitemia will test positive. A completely treated patient of p.falciparum malaria will also be positive for hrp2 for next few weeks and thus causing confusion for the treatment. However ldh based kits maybe more useful.
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In regard to the control / elimination / eradication of malaria, I am wondering if any large bodies of water / swamps are currently being gotten rid of anywhere or if any such thing is planned anywhere, i.e. as an anti-mosquito-breeding measure?
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Dear Miles,
We have worked extensively on engineering aspects of malaria control and they play a crucial role in mosquito control. For e.g. water stagnating around a community tape water supply can be directly channelized through a plastered covered drain to a pond and that will stop water stagnation and mosquito breeding. Similarly in rural areas lot of waste water gets collected in front of the houses and this can be avoided by constructing  a soakage pit through applying best engineering methods. Leveling of ditches through earth work on wasteland and thereafter tree plantation on such ground control mosquito breeding and proves to be eco-friendly method of malaria control.  Flushing of irrigation canals, lining of canals to stop water seepage and intermittent irrigation are all engineering methods of malaria control and we have successfully demonstrated it in Kheda district of central Gujarat in India.    
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Is there any dataset for ZIKA for now?
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Perhaps this a a good source.
Good luck.
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Malaria Entomologist
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Yes, we can develop certain primers for the sporozoites or the structures of the erythrocytic cycle
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Some body transfect the T. gondii tachyzoites using complicate method/s I am looking for a simple and more applicable method for transfection of siRNA to this protozoa. Is there any experience?
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Thank you so much Kathryn, but I can not take the article would you please mail me it?
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immunoparasitologists
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Tracey Lamb at Emory University (Atlanta GA USA) does some work on this. 
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During the influenza A/H7N9 epidemic in China, live bird markets have been sampled extensively to find the virus. Different types of samples were taken, including tracheal/cloacal swabs in live ducks/chickens, faeces samples, drinking water samples, waste samples, feathers, etc.
In most of the literature I could find, the proportion of positive samples of each type is given by aggregating all sample sites, i.e. authors report the proportion of positive samples of type X across all study sites (often dozens of live bird markets, all of which are obviously not infected).
What I am looking for is the proportion of samples (of each type) that tested positive in infected live bird markets. To make things even clearer, I want to get an idea of the probability that a sample of type X will test positive for H7N9 (by rtRT-PCR) in an infected market.
Any suggestion of relevant scientific papers/reports will be highly appreciated!
Thanks a lot for your valuable help.
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Or I might need to try to contact directly the authors...
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I wish to carry out a study on pinworm infection among children. I will be thankful for your suggestions on:
1. Features suggestive of pinworm or worm infestation.
2. Features increase the risk of pinworm infection.
3. Knowledge aspects need to be assessed from parents or guardians
4. Sites from which swab should be taken for pinworm eggs in the environment
Please respond to the attached delphi survey.
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I think you can take the age of kindergarten and primary school kids,continuous itching, the use of cellophane tape
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Zika virus (ZIKV) has attained worldwide attention due to its global concern and rapid pandemic potential. The World Health Organization (WHO) has declared it as a “Public Health Emergency of International Concern”. Though this virus was first isolated in 1947, its pandemic threat arises recently. The main mode of virus transmission is through mosquito (Aedes) vector. There are also other modes of virus transmission such as intrauterine, sexual and blood transfusion. Its linkage reflected for fetal anomalies and possible association with neurological disorders has crearted an alarming situation. Complete information on many aspects of this virus is yet to be available to the scientific community, which will help in designing better and effective prevention and control strategies to tackle this emergency. At present priority should be given to the mosquito control.
The whole world researchers are searching for a solution to stop its spread. Since the pathogenic potential of ZIKV is comparatively new, not much information is available regarding their genetic characterization which is most important in understanding - why the virus became virulent? What kind of mutation involved for its virulence? What are molecular differences between mosquito, mice and human adopted viruses?. The other area of interest is host-pathogen interaction studies which will provide the answers to how the viruses are crossing the placental barrier? Why it is causing microcephaly and or neurological disorders? Currently, there is no vaccine is available and scientists should focus on isolation and development of vaccine on war foot basis.  
We need to find out in details about its emergence and evolution, genetic and molecular characterization, epidemiology and timeline, current scenario, transmission and spread, clinical signs and pathology, pathogenesis, advances in diagnosis, surveillance and monitoring, vaccine development, prevention and control strategies, treatment and focus for exploring novel/emerging therapeutic regimens.
Our group of researchers recently reviewed its all salient literature available available in pubmed and compiled a very comprehensive review which is being published as a rapid communication , will be available by this March month end online (Information attached pl..)  
Zika Virus – Emergence, Evolution, Pathology, Diagnosis and Control: Current Global Scenario and Future Perspectives – A Comprehensive Review
Hence just thought to share some good information and updates with you all and also enrich myself with your knowledge and views / opinions.
The topic is now open for discussions by experts and public health officials for finding out a viable solution to save humanity from a big pandemiic?
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Google Engineers Are Trying To Help Fight the Zika Virus Outbreak
"A volunteer team of Google engineers, designers, and data scientists is helping UNICEF build a platform to process data from different sources (i.e., weather and travel patterns) in order to visualize potential outbreaks. Ultimately, the goal of this open source platform is to identify the risk of Zika transmission for different regions and help UNICEF, governments and NGO’s decide how and where to focus their time and resources. This set of tools is being prototyped for the Zika response, but will also be applicable to future emergencies..."
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Besides apparent differences in prognosis (which cannot really be objectivated nowadays) and "more" necrosis in histology samples, is there any objective clinical or pathological difference?
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I hope that following paper be useful.
Regards
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Hello, i am researching about Plasmodium knowlesi. i have read this paper
The paper still using Pmk8 and Pmkr9 to detect P. knowlesi.
But i still wondering if P. knowlesi could have a co-infection with another malaria parasit for example P. vivax. 
Can someone provide me a study that confirm a P. knowlesi co-infection using Primer used by Imwong et al 2009? http://www.ncbi.nlm.nih.gov/pubmed/19812279
Thank you
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Ron P. Marchand et al (2011)Co-infections of Plasmodium knowlesi, P. falciparum, and P. vivax among Humans and Anopheles dirus Mosquitoes, Southern Vietnam
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Can Zika virus asymptomatic host (carrier) enhance Zika transmission and spread?
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Thanks Bruce,
 Much appreciated.
Ernest
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The FDA and our federal health authority among many others have recently asked for a four weeks deferral period for blood donors coming back from regions infested by the vector and the virus.
However, since infections may be asymptomatic in blood donors, how is it guaranteed that infected donors do not harbour the virus in third spaces and in danger of a long lasting viraemia?
Do you have any specific thoughts regarding this topic?
Thank you very much in advance! 
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My dear friends. I think that high commited blood transfusion specialists like ourselves are actually paying attention very carefully and closely about the insurgence of this quite unknown virus. There is no doubt that it is very important, particularly for pregnant women, and for them, all attention must be driven from authorities in order to avoid new cases. But most importantly, if we do not fight the real culprit, the mosquito, we will certainly lose not only this battle, but the whole war. Unfortunately, this I haven´t seen not only in my country, but in several places.  This is a great forum for discussion. Regards
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How likely is it that a young person who received the MMR vaccine as a child and later developed leukemia and bone marrow aplasia will catch measles from close proximity with a sick person and develop disease? What about other vaccine-preventable diseases? 
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I don't have expertise in this area, but you could contact this researcher, he is an expert in Measles and interested in using it as oncolytic therapy, so he would probably have the answer:
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why do certain species of mosquito has affinity towards particular parasite or virus? Why don't anopheles mosquito transmit viral diseases?
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I think it needs to be noted that o'nyong-nyong virus is the one medically important  arbovirus that can be transmitted by anophelines and culicines. In practically all other instances, culicines are the exclusive or nearly exclusive vectors. In general, the main genera involved are Aedes and Culex. An arbovirus may have been isolated from numerous species but may reflect the presence of an undigested infected blood in the midgut or a salivary gland infection barrier, for example. Susceptibility must not be confused with the ability to transmit.
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Zika virus is spreading like wild fire. According to a latest report a case has been reported from Indonesia. Trained personnel is the need of the hour to halt its invasion to newer areas.
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Hi! Sumodan,
If you are interested check the following link
"Wanted: Zika virus researchers 
What are the MRC looking for? The organisation seeks twelve to eighteen month proposals that will provide novel, critical and timely insights into the nature of the risk posed by the Zika virus and/or potential avenues for its management or prevention. The MRC says that robust evidence is needed for the risks associated with Zika transmission and infection and is obtained as soon as possible. 
The MRC says that the studies should build on existing relationships, either with researchers in affected countries and/or with relevant data/resource holders. Interdisciplinary proposals are welcomed, where appropriate. 
It adds that possible avenues of research to be funded by this initiative could include:........." 
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what kind of preventive measures can be taken to avoid such epidemics in countries where specifically the hosts are breeding at an alarming rate?
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It is very difficult to commenet at this point about the potential of Zika virus epidemic in India. Theoretically India is prone to the invasion of Zika virus, as and when it occurres. Vector mosquitoes are  abundantly available , breeding sites are innumerable, susceptible population is there...it is a question of entry of the Zika virus in the Country and theoretically yes recipe is ready for the epidemic. On the other hand the example of Yellow fever virus is in contrast. In spite availability of hosts, vectors and all favourable conditions of transmission yet  we do not have the problem of Yellow Fever in India. The same might happen with Zika virus as well w- who knows
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As ZIKV RNA can be detected in the saliva, can the saliva be used as an alternative sample for routine ZIKV RNA detection. And what are the disadvantages?
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As far as I'm aware, the recent detection of Zika virus within saliva is the first reporting of its kind - very little is known at this stage as to if ZKV infection can be transmitted from human to human through saliva itself, and further testing would be required to determine this.
Relating back to your question, I imagine that it would depend on what the viral load is within saliva compared to serum/traditional sample techniques, and if this is a high enough titre to be detected consistently. 
Another thing to bear in mind is that viral RNA tends to be easier to detect in serum during the first 7 days of illness; viremia decreases over time. We would need to determine at what stage of zika infection viremia is detectable in saliva. It would indeed be interesting to see if testing of saliva samples result in a higher sensitivity/detection rate compared to traditional serum testing by RT-PCR. 
Very interesting question!
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Zikka virus is spreading across south america and the US and this is not a good sign for global public health. During the ebola outbreak in 2014 people coming from countries where the ebola outbreak occurred were isolated until cleared for the virus. should people from Zikka virus affected countries be initially quarantine??
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We need to remember that sika is a vector borne disease, which means that the way to stop or at least slow down transmission is to control de mosquito Aedes aegypti from passing the virus from infected hosts to healthy ones. The classical concept of quarantine is probably not as effective when transmission person to person is not the main mean of transmission (it is mentioned as a possibility). People infected by sika requires too a level of protection from mosquitoes to avoid to become a reservoir for the mosquitoes.
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Zika virus is considered to be more or less restricted to tropical countries. However, transmission might be possible when a competent vector (Aedes species) is present. But, the presence of a vector is not sufficient. Warm summer periods might bring favourable conditions for transmission via ektothermal insects also outside of the tropics. With climate warming, these regions are likely to increase in extent. As far as I know, there is no knowledge on the EIP (extrinsic incubation period), which would be needed to assess whether  regions and periods with the risk for transmission will evolve. Are there any hard facts, data, exeriments that can be used or applied to this virus.
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There is  limited knowledge on the EIP (extrinsic incubation period) in the field, which would be needed to assess whether  regions and periods with the risk for transmission will evolve. Are there any hard facts, data, experiments that can be used or applied to this virus. The two papers that might gives a first answer under fixed lab conditions are  (see graphics)
Li MI, Wong PS, Ng LC, Tan CH. Oral susceptibility of Singapore Aedes (Stegomyia) aegypti (Linnaeus) to Zika virus. PLoS Negl Trop Dis. 2012;6(8):e1792.
Wong PS, Li MZ, Chong CS, Ng LC, Tan CH. Aedes (Stegomyia) albopictus (Skuse): a potential vector of Zika virus in Singapore. PLoS Negl Trop Dis. 2013 Aug;7(8):e2348.
Friendly greetings from Stockholm. B.
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Using C6/36 cell line and Swiss albino mice
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Hi Monika, you could try the protocol in this paper first:
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Hello! Has anyone experience in storing field collected insects (mosquitoes in tropical climates) for insect and included parasites RNA/DNA extraction (using TRIzol/TRIreagent method) and qPCR analysis? No cold chain involved and as cheap as possible. Reviewing the literature I thought about comparing the effect of RNAlater, RNAfix (homemade RNAlater), methylated ethanol or FTA cards. I was wondering whether there are other methods that more cost-effective as possible? Many thanks! 
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Hi Corrado,
Here is a publication for the preservation of insects to be used in spectroscopy. This publication resulted from experience on field trips in Nigeria and Cameroon for insects that would be analyzed in Bamako, Mali. And Dr Floyd Dowell's experience in Tanzania. It is good you are not involving cryo-preservation at any point in the tropics.
I may suggest SILICA GEL for a short period. I had serious degradation of materials preserved in ethanol on one hand and on the other hand, methanol fixes molecules and may not yield very good results during DNA/RNA extraction.
I hope this helps
good luck
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Hello!
I would like to ask if there are any reliable data what is the best prophylactic method as it comes to Leptospira infection?
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"Immunization by means of vaccines seems to provide a certain degree of protection. Vaccines are, in principle, suspensions of killed leptospires. Protection is largely serovar-specific. In areas where many serovars are causing leptospirosis, a vaccine must consist of different serovars matching those circulating locally. In some countries,  where many serovars occur, vaccines consist of a mixture of a few of the most prevalent. Protective antibodies are produced only against the serovars present in the particular vaccine used.
Commercial human vaccines have been produced in France and Cuba. However, these vaccines do not induce long-term protection against infection and do not provide cross-protective immunity against heterogenous leptospiral serovars."
From WHO fact sheet
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Can you identify these hemoparasites that i found in rodents?
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I don't think anybody can identify them on the basis of these pictures, certainly not as long as no multiplying forms are shown. And even then, one would need molecular tools.
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Have a patient currently being managed for both, Dengue fever, and Typhoid fever. Wanted to know if either one of the two reports could be a false positive. Kindly cite references for the same, if possible. Thank you !
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This could be case of co- infection of Dengue + Typhoid . The major problem for the clinician is  analyzing the reports . For eg. It could mean that the patient had typhoid in the past & Dengue at present with anamestic rise of widal titres . It is preferable to look for features such as thrombocytopenia for dengue & splenomegaly for typhoid . It is preferable to treat both ,as the patient's health is more important than to take a risk in not treating . It should be explained to the patient the rationale behind treatment or questions will be raised about the validity of the tests on why we did these tests , if we do not trust the reports .
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24 year pregnant lady presented with high grade fever with altered sensorium, diagnosed to be a case of complicated falcipaum malaria, but with very high level of uric acid (17.4 mg/dl), she responded to Inj Artisunate plus Clindamycin and her uric acid level also gradually becoming normal without any hypouricemic drugs. A second patient with long standing history of gouty arthritis with multiple tophi presented with acute severe pain and high grade fever, malarial test was positive and he responded to antimalarial and there also respond to his arthritis (he was also on colchicine)....now, my question is whether antimalarial has any effect on hyperuricemia?
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Dear ,referring to added link.Thanks
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Recently, I have concluded a preliminary study on Habitat Diversity Index for Aedes albopictus and its relevance in comparing endemicity to Dengue and also in planning control strategies. Now I need to elaborate the study to reach a precise conclusion. I will share the protocol with those who are interested. I am also open to modify the protocol based on their inputs. 
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Thank you. Please give your email ID
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for example polio and RCH has been given enough emphasis for social mobilization and development communication. Tropical diseases and especially leprosy have rarely been addressed with such vitality. can mass level mobilization and awareness creation about the disease be helpful in eradicating?
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Apart from awareness creation about basic symptoms of disease, a lot needs to be done in the area of stigmatization. Infected persons especially females may be reluctant to seek medical help because of stigmatization, and this will hinder control efforts. So emphasis of the social mobilization should rest more on sustained, simple and repetitive information to discourage discrimination against infected and affected persons. This is very vital. Advocacy visits to political leaders and government should engender the desired shift in priority from curative to preventive programs such as community mobilization for adequate participation. In other words, advocacy can lead to political will and commitment by Government in favour of leprosy control and eradication.
also be carried
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 monoclonal antibody  against IL2. TNF. IL1. etc.
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There are no current classical antibodies to neutralize DENV, but there is a new development that shows promising results (antibodies against the E dimer conformation region, please refer to Galvin Screaton 2015), also there has been extensive research showing that the permissive cells in vivo are of stem cell which bear megakaryocyte phenotypes, this could also help understand dengue and develop strategies against it
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It is often the case that  researchers who work  on topics unique to the tropical regions of the world try to publish their work in journals based in the developed temperate countries. This frequently leads to their papers being rejected on grounds that they are only of regional interest. Hence, its best if we support our own regional journals so that these journals will become better known and of high quality by having good papers submitted and published in them.
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 I'm semi-retired so have the luxury of ignoring impact factors, but my younger colleagues don't have that choice because university administrators and other gatekeepers have become obsessed with supposedly "objective" indicators of "quality." It's perverse, unfair, and stupid, but it's reality.
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We are seeing lot of viral thrombocytopenic fevers which test negative for Dengue serology and even PCR but have a clinical picture similar to Dengue.
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Because we have ruled out bacterial infections with appropriate tests and left with a huge chunk of patients with clinical picture similar to Dengue fever
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I'm having a problem with this model because the virus isn't causing plaque lysis in the cell monolayer. To titrate, I'm using a semi-solid medium (carboxymethyl cellulose 1,5% plus 1,5% of FBS) over 5 days of incubation. Could be something wrong with the cells or maybe with the semi-solid medium?
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I have never been able to get a plaque assay working for dengue virus. I have found that an immunoperoxidase staining assay is a good way to determine titers. Here is the method that I use from Durbin et al. 2001. ATTENUATION AND IMMUNOGENICITY IN HUMANS OF A LIVE DENGUE VIRUS
TYPE-4 VACCINE CANDIDATE WITH A 30 NUCLEOTIDE DELETION
IN ITS 3-UNTRANSLATED REGION
Vero cell monolayer cultures in 24-well plates. After a 1-hr incubation at room temperature, the monolayers were overlaid with 0.8% methylcellulose
in OptiMEM (Life Technologies) supplemented with 5% FBS. Following incubation at 37C for four days, virus plaques were visualized by immunoperoxidase staining.
Briefly, cell monolayers were fixed in 80% methanol for 30 min and rinsed with antibody buffer (5% nonfat milk in phosphate-buffered saline). Rabbit polyclonal DEN-4 antibodies were diluted 1:1,000 in antibody buffer and added to
each well followed by a 1-hr incubation at 37C. Primary antibody was removed and the cell monolayers were washed twice with antibody buffer. Peroxidase-labeled goat-anti-rabbit IgG (Kirkegaard and Perry Laboratories, Gaithersburg,
MD) was diluted 1:500 in antibody buffer and added to each well, followed by a 1-hr incubation at 37C. Secondary antibody was removed and the wells were washed twice with phosphate-buffered saline. Peroxidase substrate (4-chloro-1-
naphthol in H2O2) was added to each well and visible plaques were counted.
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Since ending 2013 I have read that there was a discovery of a new (the fifth) serotype of dengue in Asia, however, no published specific paper on it has become public. In fact many short notes, comments and letters discuss that finding, but the original research or the study has not yet been published.
Apparently Nikos Vasilakis has made the discovery, but has not yet shown in any scientific journal.
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Dear Alfonso,
what I learned from Nikos Vasilakis presentations during several arbovirus conferences/meetings held in Germany last year and this year was that the classical definition of dengue "serotypes" needs to be revised because it do not fit with the genetic characterization of the "novel" strain. Beside this, it is more likely to be a new genotype of serotype 4. However, the discussions are ongoing and I believe Nikos is trying to convince the reviewers with additional experimental data...
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I was in the field in S America when two team members got dengue, one for the first time. The professor had had another serotype in Africa and had severe hemorrhagic fever and the sheets were soaked in blood and the fever of 106 didn't break for over 5 days.
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Dear Terri and Alfonso,
although CHIKV can invade endothelial cells, these are clearly not its elective target cells to cause, Th1 cytokine-driven plasma leakage and related organ dysfunctions leading to hemorrhagic fever syndrome (as for Dengue). As Alfonso wrote, to date there have been to few co-infections documented so that from a public health point of view, it may seem impossible to answer. However, the introduction of CHIKV in areas where DENV is prominent (Americas, Pacific, SE Asia) offers a good opportunity to answer your question in a larger extent and the potential interactions between the two viruses is an exciting issue to be solved. From my experience, in La Réunion island (266,000 cases of CHIKV in 2005-2006), mild bleeding manifestations in the setting of CHIKV infection were not so infrequent, while clearly severe hemorrhages were scarce and decreased with age (neonates >> infants > children > adults) or occur in adults with severe comorbidity (diabetes, alcohol-related hepatic dysfunctions, etc...). As a pediatrician involved in the first description of mother-to-child transmission of CHIKV, we documented hemorrhagic syndromes in neonates in the absence of bacterial, fungic or viral co-infections. Finally, even it may also depend on host factors, the interaction between the two pathogens remains to be explored (keeping in mind alphaviruses and flaviviruses are very different pathogens). I fully agree with Alfonso, many things with chikungunya are to be studied. Best wishes
pg
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Take a look at this review
A toolbox to study liver stage malaria - Cell
 
 
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HI;
May any one tell me what's the best method to purify and quantify Leishmania amastigotes from spleen and or liver. We've tried parasite burden by limit dilution and it didn't work well.thank's
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The following is an extract from Wyllie and Fairlamb Acta Tropica 97 (2006) 364–369:
"The spleens of infected animals were aseptically removed, weighed and homogenized in Dulbecco’s modified essential medium (D-MEM, Sigma) containing 10% (v/v) foetal calf serum, 20mM l-glutamine and 10mMsodium pyruvate. The homogenate was then centrifuged at 100×g for 5 min at 4 ◦C to remove large cell debris, supernatant collected and centrifuged at 2000×g for a further 10 min at 4 ◦C. The resulting pellet was resuspended in culture medium containing 0.05% (w/v)
saponin and incubated at room temperature for 5 min. Following centrifugation (2000×g, 10 min, 4 ◦C), the amastigote-enriched pellet was washed twice in fresh
culture medium before being resuspended in a final volume of 2 ml. The amastigote suspension was passed through a 23-G needle several times to disperse clumps
prior to counting."
Cells are counted microscopically using a Neubauer counting chamber. A Percoll gradient could be used for additional clean up as suggested above.
Best wishes
Alan Fairlamb
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Hello! Some days ago a sample from a patient possibly infected with schistosoma was sent to our laboratory for molecular analysis. The diagnostic was done by a rectal biopsy and staining with Ziehl-Neelsen. Some of my colleagues claim that only could be S. mansoni and S. intercalatum because only eggs from these spieces stain. However, in my opinion, eggs are not stained and it could be S. haematobium. Please, can anyone help with this question?
(I attach photographs of the rectal biopsy. The last 2 photography is the rectal biopsy of other patient with confirmed S. mansoni infection)
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As mentioned by Mahmoud Elsibaei, usually S. haematobium eggs does not appear in rectal biopsies, but it's not impossible. Although I have not much experience with histological preparations, I can tell that normally, with a Ziehl-Neelsen stain, S. haematobium is the only Schistosoma egg that is NOT acid-fast and thus will not stain red. All the other Schistosoma species eggs would stain acid-fast (red). Easiest would be to use the morphology off the egg, but as Unu Airauhi said, the spine, used in this case, is not always visible. Much will depend on where the egg has been cut.
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yes, that is correct, just read the ECDC statements on Dengue:
Potential vectors are not as likely to carry diseases-competent virus' as they might be in Brazil and/or other countries with mediterranean climates. But in European countries with suitable climate (e.g. mediterranean), the issue is currently discussed.
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Dear Colleagues,
Has anyone recent information (> 2004) on the antifeedant and/or repellent activity of neem limonoids (other than azadirachtin) on insects?
Please send or mention.
Many thanks!
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Hi Sibylle
Sorry I missed the notification of your response to my comments in October and have just picked it up.
When I refer to the "claimed repellent effects of neem limonoids" I was thinking of the claims made by those people using neem and its extracts for deterrence of blood feeding insects such as mosquitoes, fleas, and lice.  As far as I can see these are just claims with no real substantive evidence in support of those claims.
 If neem extracts do repel in the true sense it would have the opposite effect from that which is required for the anti-feedant effect, i.e. phytophagous insects should be repelled from treated plants, which we can reasonably assume not to be the case because those insects do feed off neem treated plants and suffer the anti-feedant effect as a consequence.  
My suggestion is that products containing neem that are sold for repelling mosquitoes etc may derive their activity from some other component of the formulation or perhaps, at the most basic level, the insects are deterred from biting either by the sticky nature of the neem oil component or else the unpleasant allium-like odour of the neem.
With regard to the comment "....we have looked for effects of mixed limonoids in other ways and to be honest we have never been able to identify any activity of any kind against the insects we deal with....." I was referring to the claimed effects of neem to kill blood feeding insects, such as lice, when applied topically to the insects.  There are numerous products on sale around the world that are claiming efficacy from azadirachtin and the other large limonoids against insects that could not possibly ingest the compounds due to their blood feeding habits and these compounds could also not possibly enter the insects via the cuticle.  Hitherto none of these products has a defined mode of action but the makers imply that as neem is considered a "wonder" insecticide the products work in a similar way to how neem controls phytophagous insects.  Largely a matter of BS baffles brains, as most of the purchasers have no idea how the material works against any insect - they just like the idea of a natural "wonder drug".
Ian
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Recent field tests with human-derived odorants for mosquito attractants to traps did not include consideration of L-lactic acid as part of the human-produced odor blend plus CO2 (Acree et al., Science, 161:1346-1347,1968).  Since lactic acid does not elute from a GC column, conventional GC-MS does not see or record it.  
Is there a better direct analytical method? 
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I'm not a chemist but you may want to have a look at Benier and others (2000 and 2001) analyzing skin emanations. They were able to detect Lactic acid through conventional GC-MS in spite of the difficulty.Picking from the work of Benier, the Takken lab at Wagenigen university, Netherlands have evaluated Lactic acid as a synergistic attractant of Anopheles gambiae s.l.. The compound is now considered an active part of synthetic blends for trapping malaria mosquitoes (Kline et al 2007; Okumu et al 2010; Olanga et al 2010; Mukabana 2012). The effectiveness of these blends is currently being evaluated in relatively large field trial in Rusinga Island under the umbrella of Solarmal - a malaria project that seeks to reduce malaria transmission using odour-baited mosquito traps. This might be totally irrelevant. I just though I might add it here :)
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Gastropods and other molluscs are often obligate hosts for trematode parasites, many of which are important pathogens.  I am interested in developing a list of such molluscs that show the potential for invasion of new habitats around the world, and argue that there is a need for more biomonitoring for such situations as potential emerging disease threats of humans and/or animals.
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Dear colleagues.
One Black Sea Basin snail - Lithoglyphus naticoides and its trematodes (both European and American populations )?
I think Dr. Mastitsky agree with me.  
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I wish to identify/characterize marine fungi associated with various marine organisms found on tropical reefs. I have found numerous papers on sampling of sediments and wood fragments but need protocol for live substrate sampling.I would also love to establish a line of communication with a marine mycologist.
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The first step is DNA extraction , then  universal primers could be selected for fungi identification, according to different manuscript written in the field. then you can narrow your research and go ahead.
Regards
Dr. Abdigoudarzi
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What do you think about your lab safety rules? Do you respect them? Do you remember to use a "one glove rule"? How safety may be improved in your work spaces? I enclosed a very well prepared Laboratory Checklist, maybe someone would like to use it.
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Thanks for the checklist
Cheers
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Rodents are reservoirs of many zoonotic diseases to human and their infested fleas,mites,ticks and lice act as vehicles transmitters of infections to man.What is best apply ant-ratting or insecticide first?
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Rodents indeed serve as reservoirs for many zoonotic diseases.  Many of these diseases are transmitted via parasitic arthropods, but others are transmitted simply by contamination of the environment by rodent feces or urine.  Also, many arthropod parasites of rodents do not survive long away from the host, and many do not prefer humans as hosts.  Thus, rodent-associated zoonotic diseases that involve synanthropic arthropod transmission actually circulate most effectively in the presence of healthy rodent populations close to human habitation or activity.  Thus, I would start with control of the rodents, then move to comprehensive sanitation of human activity areas that would eliminate both arthropods and other infectious contaminants.
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In order to detect human blood in blood-sucking insects.
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Thanks!! Do you think that primers designed to amplify Alu do not cross-react with other vertebrate or insect DNA?
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I want to be able to tell when a gene reassortment event (observed after DNA sequencing of genes of pathogens) occured.
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It is possible that it was happened. There are processes which indicate re assortment, as genes of body color are expressed due to change in the environment, they appear only due to switch on gene activity. when temperature and ecological factors they again become normal a silent copy of gene which can not be traced by molecular methods appear. As use of drug making the insects and micro-organisms resistant only due to exposure. If exposure is not provided then they come back to their normal position. Alienation and de-alienation always happen with the chance and frequency of mutations in important genes which are highly susceptible to  environmental changes.  
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I consider that in the current setting we are facing in some countries, measure this is highly important. Then, I would like to know if there exists questionnaires for that.
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Dear Alfonso, I have a PhD student who recently completed a very comprehensive series of 3 systematic reviews, on disease management, surveillance, and mosquito control as well as an analysis of guidelines on Chik V fever.  While it did not cover your specific question, if you wish i can message you contact details for the student.  Overall, what the evidence suggests though is that knowledge of Chik V is low, especially knowledge of presenting symptoms and symptom based treatment. It seems misdiagnosis is common which creates risks for patients who are not effectively monitored or managed since they do not have a proper diagnosis.  Do let me know if you want to be put in touch with this recently completed PhD student.
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I want to work on placental schistosomiasis using animal model. Is it possible to use mice?
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Dear Olufunmilola,
I guess that you are working with Schistosoma mansoni or S. japonicum because these species are usually associated with placental schistosomiasis. In designing experimental or quasi-experimental studies on schistosomiasis, one has to pay attention to the type of animal host that serves as the most permissive one for infection. Mice are the best choice for S. mansoni while guinea pigs are best for S. japonicum. These two types of hosts are quite refractory to infection with S. haematobium, which is rarely associated with placental infection.
Hope this helps.
Kind regards,
Rashad
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I'm adjusting the sensitivity of different molecular methods for the detection of Schistosoma and want to know how much DNA is in an egg. I'm reviewing the literature and find nothing. Please, can anyone help me?
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Sorry Javier,
I do not have data about amount of DNA in the Schistosoma egg. But, was related by Ana Liza Gomes et al. 2006 that the genome of the S. mansoni worm weighs 580fg.
The best,
Edward Oliveira
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I have lots of sequences to align and I used to use MEGA6 but it takes forever to finish one multiple alignment session. I need a faster and a more accurate way of obtaining my multiple alignments.
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If you are looking for a purely online program I prefer ClustalW over MAFFT. I find that my alignments are a little better as it gives me the option to input a few more parameters. That being said, there are much better programs out there if you have the CPU to handle as Jainder Chhillar suggested.
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If you consider Msp2 as a marker for genotyping a sample containing multiple infections infected with 2 or more clones, is there any formula for calculating MOI ? If yes, how can we calculate using a formula?
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Hi, multiplicity of infection (MOI) is calculated by dividing the total number of alleles (fragments of all alleles or genotypes in a gene) by the number of samples positive for the same marker (eg: MSP1). below is the detail that i have found for the MOI calculation, the way that the author did:
family family pos. allele freq. msp1 pos MOI/family
k1 19 56 36 1.6
mad20 25 67 44 1.5
ro33 20 52 34 1.5
total 64 175 114 --
MOI/total 2.7 1.5 -- --
hope the table reach you in a good format. any way , MOI was calculated two times; 2.7 as an MOI of the whole msp1 gene and 1.5 -1.6 for each family (k1, mad20 and ro33). my opinion is to calculate MOI for the msp1 by dividing 175 (total genotypes) by 114 (36+44+34) but not (19+25+20), and it will be very closer to the allelic MOI (1.5).
hope this details being useful for u.
Below is a link to my own publication regarding msp1 and msp2 genetic diversity.
all the best
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Biomphalaria glabrata is the intermediate host for the important human blood fluke, Schistosoma mansoni, present in parts of the Caribbean. Establishment of this species in suitable habitats in southern Florida could lead to a potential for establishment of this disease on the U.S. mainland, in areas where substandad human waste treatment and/or zoonotic connections might occur. I am just seeking to determine whether anyone is looking intentionally at this through ongoing targeted surveillance.
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Clive, Thank you for your reply. This 2012 IAMAT document on shistosomiasis risk throughout the world (http://www.iamat.org/pdf/World_Schistosomiasis_Risk_Chart.pdf) makes it appear as though there are still infections taking place in Puerto Rico (apparently they haven't updated the status for Puerto Rico in a while). Thanks for the information.
There is at least one established B. glabrata population in Mississippi as I noted in an earlier post. It was only recently reported at a regional invasive species meeting (GSARP) . People had concerns that this new snail introduction could eventually lead to shistosomiasis disease in the area, so your comments help to put that risk into perspective.
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I have infected macrophage cell line (THP-1) with Leishmania parasite and now I want entrapped parasite to be used for culturing. How do I let the parasite free from macrophages without harming parasite's viability.
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It depends if you want the live leishmania on the promastigote or amastigote form. Just plating the cells at 28 °C for a week in leishmania M199 medium (or even RPMI with serum) is enough to free up the promastigote parasites.
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We are probing primers designed for TNF-alpha, IL-6, IL-17, IL-23, IL-10 and IL1b, in order to determine expression levels of these cytokines in heart of mice infected with Trypanosoma cruzi. The paper that we got the primers sequences reported a PCR product between 100-300 bp, but we obtained pcr products of 50 bp in heart. We did a positive control with spleen of infected mice, but in that case the products are quite different, higher to 300 bp. If anyone has experience in this topic and can help me, I would be very thankful.
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I agree with Dr Manuja (above); the 50bp product is almost certainly a primer dimer. To help you, you'll need to describe the reactions in question, in detail...
I'd always encourage you to design your own primers rather than take those from a paper, especially if it's more than a couple of years old. The reason is that PCR has advanced technically so far in such a short space of time. Also so many things can affect a reaction that you really need to work it up using your own tubes, reagents, machine... Basically it's easier working it from scratch than trying to troubleshoot someone else's.
You have 6 qRT-PCR reactions, I assume (TNF, IL-1b, IL23p19, IL-10 and IL-6). First, decide on the annealing temperature of the primers that you want for all the reactions, the product length range and the reaction efficiency acceptable to you. It's perfectly possible to design 6 (or sixty) qRT-PCRs with the same conditions; unless they have the same reaction efficiencies, you can't cleanly compare their relative levels. Then, make sure your primers are bedded in different exons. Have one primer wholly within an exon and the other overlapping an exon-exon junction by three or four nucleotides (not more). Be SURE that those 3 or 4 nucleotides do not match the intronic sequence adjacent to the exon where the bulk of the primer is located otherwise you may get DNA amplification. Now, prepare a standard source or cDNA that contains all your targets - splenocytes activated with poly-IC and LPS (together) will be good for the cytokines you're suggesting. Lastly, you're now able to begin testing primer sets and working out the reaction efficiencies in order that you can begin your experiment. Of course, your housekeeping genes (two is preferable) have to be designed the same way. Avoid intronless genes as housekeepers. Good luck!!
G
ps - my answer assumes you have access to a real-time apparatus. If you do not, then it is very difficult to get reliable quantitative data, even relative quantitative data.
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I found that [Artesunate plus sulfadoxine–pyrimethamine] is now being used as first-line treatment for Malaria in India, since 2010.
What is the second-line of treatment for Malaria at present?
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Dear Ravi,
To my knowledge there is not any such first or second line treatment for malaria as such. However there is treatment guideline with respect to the type of parasite found to be present in malaria fever patient as well as according to the complication/severity status.
You may like to refer the recent treatmment guideline issued by NVBDCP in 2013
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Or information on the progress in the development of its vaccine? The vector is the Aedes mosquito; and the DENV (dengue fever virus) is an RNA virus.
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The Aedes mosquito can be controlled through fishes (Poecilia), small crustaceans, in small artificial deposits like water tanks baby turtles has been used (Trachemys scripta) to predate on Aedes larvae https://www.researchgate.net/profile/Gerardo_Borjas/publications.
Some products with biological spores have been used in some countries: Bacillus sphericus and Bacillus turingiensis var israelensis (Bti) but there is controversy about if this a chemical or biological product.
About the vaccine, there is an expectation that in less than five years we'll have one, since several pharmaceutical companies are working in its development with a very strong support from Universities and International Organizations. The information has been summarized in previous entries
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There are several pheromones/oviposition attractants identified and reported in publications of prestigious journals since 1980's, for some blood sucking insects that are highly promising for use in vector management. However, I would like to know about the commercialization of such effective semiochemicals (if any) that will be helpful for managing especially vectors that transmit malaria, dengue, encephalitis, leishmaniasis etc.
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Field study and useful description of reliable mosquito traps to combine with oviposition candidates....
Comparison of CDC and EVS Light Traps Baited with Carbon Dioxide and Octenol for Trapping Mosquitoes in Brisbane, Queensland (Diptera: Culicidae)
SCOTT A. RITCHIE, DANIEL L. KLINE
Australian Journal of Entomology (Impact Factor: 0.88). 03/2007; 34(3):215 - 218. DOI:10.1111/j.1440-6055.1995.tb01322.x
ABSTRACT Studies were conducted in Brisbane, Australia to test the efficacy of encephalitis virus surveillance (EVS) and Centers for Disease Control (CDC) mosquito light traps. Additionally, the relative attractiveness of different combinations of light, carbon dioxide (dry ice) and l-octen-3-ol (octenol) was assessed. the CDC light trap consistently collected more mosquitoes than the comparably baited EVS trap. Octenol, supplemented with dry ice, significantly increased collections of Aedes vigilax, Aedes procax and Culex annulirostris but not Aedes notoscriptus.
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My favorite insect research subject is the mosquito, but now I'm about to pick up my future vehicle, and I don't want to deal with it in matter of likeness, so I'm to take all related factors into consideration.
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I believe the question is very hard to answer. In addition to all the human vector borne pathogens you have the pathogens that are spread between animals and between animals and humans. Most of the emerging diseases are vector borne and many of them are mosquito borne. There are probably several vector borne pathogens that are yet undetected. If you are looking into a future career I can assure you that medical and veterinary entomology is a fulfilling way to go with never ending challenges and rewards!
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I would like to perform IHC to target specifically on brain cysts of Toxoplasma ME49 found in balb/C mouse's brain. Is it possible to do that? Is there any commercially available kits to perform this task?
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I think u need specific monoclonal antibody during the processing of the sample,,, this will be followed by coating with a dye either fluorescent or not..I am not sure what is available but u can ask pathologists
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I am looking for live L3 larvae of Anisakis simplex, Pseudoterranova decipiens, Contracaecum sp. and Hysterothylacium sp. for serological investigation. Would anyone be kind to help me get these parasites?
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If you have access to unfrozen European herrings, these will be heavily infected, since they're the intermediate and/or paratenic hosts for both Anisakis and Contracaecum (and probably the other two species, as well). Get the raw herring, grind them up in a blender and digest them with artificial digestive fluid (HCl-pepsin) at 37 C (follow Trichinella protocols) and then isolate the larvae using the Baerman technique.
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For bacterial assay and hemolymph extraction.
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We use diluted heparin in hemimetabolous insects, and it works
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I've been running indirect ELISAs using Apical Membrane Antigen-1 and Merozoite Surface Protein-1 to test serum samples from a low transmission region for previous exposure to malaria. A majority of our sample are under the age of 18, however the literature is unclear as to what the window for detecting malaria antibodies are using these antigens. Does concordance between antigens suggest a more recent exposure? If someone could elaborate or recommend literature explaining detection thresholds and windows for these two antigens I would greatly appreciate it.
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In 18 year olds even in low transmission regions I would expect antibody to at least one of the antigens, though which one comes up more prominantly is hotly debated and possibly region dependent. The below literature should help. I have looked at both of these antigens following controlled human malaria infection (equivalent to a low dose, single exposure) and I see antibodies only to MSP1 not AMA1. You can find out more from my most recent paper, though I focus more on b cells that antibody.
Wipasa J, Suphavilai C, Okell LC, et al. Long-lived antibody and B Cell memory responses to the human malaria parasites, Plasmodium falciparum and Plasmodium vivax. PLoS Pathog 2010;6(2):e1000770.
Clark EH, Silva CJ, Weiss GE, Li S, Padilla C, Crompton PD, Hernandez JN, Branch OH. Plasmodium falciparum malaria in the Peruvian Amazon, a region of low transmission, is associated with immunologic memory. Infect Immun 2012;80(4):1583-92.
Nogaro SI, Hafalla JC, Walther B, Remarque EJ, Tetteh KK, Conway DJ, Riley EM, Walther M. The breadth, but not the magnitude, of circulating memory B cell responses to P. falciparum increases with age/exposure in an area of low transmission. PLoS One 2011;6(10):e25582.
Dorfman JR, Bejon P, Ndungu FM, et al. B cell memory to 3 Plasmodium falciparum blood-stage antigens in a malaria-endemic area. J Infect Dis 2005;191(10):1623-30.
Kinyanjui SM, Conway DJ, Lanar DE, Marsh K. IgG antibody responses to Plasmodium falciparum merozoite antigens in Kenyan children have a short half-life. Malar J 2007;6:82.
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I need S.haematobium DNA to continue with my PhD. If anyone knows where to buy it or get it, please tell me.
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Thank you very much. Also I have another question: do you know which method is most appropriate to concentrate S. haematobium eggs before DNA extraction? and, What protocol should I use for extraction?
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In my country, dengue cases have increased from around 18000+ in 2012, to 28000+ this year. Deaths due to this viral disease has also increased from 21 to more than 60 this year. How about in your country?
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