Loop-mediated isothermal amplification of DNA (LAMP): a new diagnostic tool lights the world of diagnosis of animal and human pathogens: a review.
ABSTRACT Diagnosis is an important part in case of animal husbandry as treatment of a disease depends on it. Advancement in molecular biology has generated various sophisticated tools like Polymerase Chain Reaction (PCR), its versions along with pen-side diagnostic techniques. Every diagnostic test however has both advantages and disadvantages; PCR is not an exception to this statement. To ease the odds faced by PCR several non-PCR techniques which can amplify DNA at a constant temperature has become the need of hour, thus generating a variety of isothermal amplification techniques including Nucleic Acid Sequence-Based Amplification (NASBA) along with Self-Sustained Sequence Replication (3SR) and Strand Displacement Amplification (SDA) and Loop mediated isothermal amplification (LAMP) test. LAMP stands out to be a good and effective diagnostic test for empowering in developing countries as it does not require sophisticated equipments and skilled personnel and proves to be cost-effective. Performance of LAMP mainly relies on crafting of six primers (including 2 loop primers) ultimately accelerating the reaction. LAMP amplifies DNA in the process pyrophosphates are formed causing turbidity that facilitates visualisation in a more effective way than PCR. The Bst and Bsm polymerase are the required enzymes for LAMP that does not possess 5'-3' exonuclease activity. Results can be visualized by adding DNA binding dye, SYBR green. LAMP is more stable than PCR and real-time PCR. Non-involvement of template DNA preparation and ability to generate 10(9) copies of DNA are added benefits that make it more effective than NASBA or 3SR and SDA. Thus, it fetches researcher's interest in developing various versions of LAMP viz., its combination with lateral flow assay or micro LAMP and more recently lyophilized and electric (e) LAMP. Availability of ready to use LAMP kits has helped diagnosis of almost all pathogens. LAMP associated technologies however needs to be developed as a part of LAMP platform rather than developing them as separate entities. This review deals with all these salient features of this newly developed tool that has enlightened the world of diagnosis.
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ABSTRACT: Irrespective of aetiology, infectious respiratory diseases of sheep and goats contribute to 5.6 percent of the total diseases of small ruminants. These infectious respiratory disorders are divided into two groups: the diseases of upper respiratory tract, namely, nasal myiasis and enzootic nasal tumors, and diseases of lower respiratory tract, namely, peste des petits ruminants (PPR), parainfluenza, Pasteurellosis, Ovine progressive pneumonia, mycoplasmosis, caprine arthritis encephalitis virus, caseous lymphadenitis, verminous pneumonia, and many others. Depending upon aetiology, many of them are acute and fatal in nature. Early, rapid, and specific diagnosis of such diseases holds great importance to reduce the losses. The advanced enzyme-linked immunosorbent assays (ELISAs) for the detection of antigen as well as antibodies directly from the samples and molecular diagnostic assays along with microsatellites comprehensively assist in diagnosis as well as treatment and epidemiological studies. The present review discusses the advancements made in the diagnosis of common infectious respiratory diseases of sheep and goats. It would update the knowledge and help in adapting and implementing appropriate, timely, and confirmatory diagnostic procedures. Moreover, it would assist in designing appropriate prevention protocols and devising suitable control strategies to overcome respiratory diseases and alleviate the economic losses.Veterinary Medicine International. 06/2014; Volume 2014 Special Issue(Article ID 508304):16 pages.
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ABSTRACT: Coronaviruses are positive-sense single-stranded ribonucleic acid (RNA) viruses causing a broad spectrum of diseases in domestic and wild animals including poultry and rodents. Based on antigenic and genetic similarities coronaviruses have been subdivided into three major antigenic groups. They infect and produce disease in multiple species of animals, human beings (groups 1 and 2) and birds (group 3). Equine coronavirus (ECV) causes enteritis in foals. Complete genome of first ECV isolate NC99 strain has been recently sequenced. Cytolytic nature of the virus is responsible for occurrence of lesions in the small intestine, thereby causing diarrhea. Demonstration of coronavirus antigens in clinical samples is test of choice for diagnosis. By electron microscopy (negative staining) coronavirus-like particles can be identified in fecal samples. Coronavirus antigen in fecal samples can be detected by antigen capture enzyme linked immuno-sorbent assay (ELISA). Molecular detection tool like reverse-transcriptase polymerase chain reaction (RT-PCR) has made the diagnosis more accurate. Virus characterization along with genogrouping has become easier these days with the advent of proteomics and phylogenetic studies. Currently, no vaccine is available for ECV. Biosecurity measures if adopted strictly prevent the disease. The present review highlights the salient features of the coronavirus in general with special reference to ECV and the disease it causes in equines, its epidemiology, diagnosis, and appropriate prevention and control measures to be adopted. The review would be helpful for understanding the virus / disease in a better way and alleviating economic losses to the equine / stud farm owners.Asian Journal of Animal and Veterinary Advances 04/2014; 9(3):164-176. · 0.87 Impact Factor
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ABSTRACT: Toroviruses are responsible for causing gastroenteritis in animals and humans. These are enveloped viruses with non-segmented and positive-sense (single stranded) RNA genome of 20 to 25 kilobases, pleomorphic, and are associated with diarrhea in cattle, sheep, goat, pig and other animals, and also in human beings. Morphological appearance of viruses is spherical/oval, elongated or kidney shaped. These show Torovirus-like (tubular and torus nucleocapsid in the cytoplasm of infected cells) appearance under the electron microscope, and are approximately 100-140 nm in diameter, surrounded by club-shaped projections of 15-20 nm in length. Clinical signs of the disease are pyrexia, diarrhoea, dehydration, lethargy and depression in calves as well adults. In calves, the virus may lead to anorexia, mucoid faeces and neurological signs like generalised weakness, paralysis, inability to stand along with trembling and sudden death. In faecal samples, these can be identified by electron microscopy. Immunological tests include immuno-electron microscopy (IEM), haemagglutination inhibition (HI), enzyme linked immunosorbent assay (ELISA) and southern blot. The molecular assays are reverse transcription-polymerase chain reaction (RT-PCR), nested-RT-PCR and SYBR Green real-time RT-PCR. Combined use of ELISA and RT-PCR are considered is a practical approach for epidemiological studies of bovine torovirus. At present, no vaccine is available for torovirus. The only control measures available are good hygiene and sanitary conditions along with isolation of infected animals. The present review highlights the salient features of the torovirus, their epidemiology, clinical signs, diagnosis, treatment, and suitable prevention and control measures to be adopted.Asian Journal of Animal and Veterinary Advances 04/2014; 9(3):190-201. · 0.87 Impact Factor
0-60 bp 40-60 bp 120-160 bp
F3C F2C F1C B1 BLP B2 B3
F3 F2FLPF1 B1C B2C B3C
FJP = F2+F1C BJP = B2+B1C
5’ + 3’ 5’ + 3’
Outer primers loop primers
Target regions of primer and qualities of LAMP primer
Lamp-procedure and advantages at a glance
Unprocessed samples can also be used
Water bath for
Gel-ladder like pattern
No need of
No need of