Human cytomegalovirus is a herpesvirus that has a worldwide seroprevalence of more than 60% of adults in developed countries and 90% in developing countries. Severe disabilities in newborns are characteristic of the human cytomegalovirus congenital infection, and this virus is implicated in graft rejection in transplant patients. To treat and follow-up the infection, the CMVPCR viral loads are required, and the DNA extraction step remains very important; however, the quantity, quality, and purity of extracted DNA from different biological fluids influence the results of PCR amplification, that is why for reliable results, the choice of nucleic acid extraction methods requires careful attention. Materials and methods: In this study, we compare 4 protocols, I (EZ1 DSP Virus kit), II (EZ1 Virus mini kit), III (QIAamp DSP virus kit), and IV (heating); the extractions are made from plasma collected on EDTA tubes, and the concentration of extracted DNA was measured on NanoDrop Lite followed by real-time CMVPCR using an Artus CMV QS-RGQ kit. All protocols are performed following the manufacturer’s instructions. Results: This study is conducted on the samples of 135 transplant patients whose follow-up medical tests related to human cytomegalovirus infection; since most of the CMVPCR results are negative, we have chosen the 10 CMVPCR positive samples and 2 negative samples as controls to conduct this comparison study. By using NanoDrop Lite to evaluate the DNA concentration, the yield of extracted DNA is higher in our heating protocol than other protocols, the EZ1 DSP virus kit and EZ1 Virus mini kit show homogeneous quantities, and the QIAamp DSP virus kit shows very low DNA yields. Comparing cycle threshold and viral loads by real-time PCR, all these protocols identified negative samples (100%), and the previously positive samples used were as follows: protocol IV (90%), protocol II (60%), and protocol I (40%). QIAamp DSP virus kit results were not real-time PCR applicable and were non-conclusive because of the low DNA yields. Conclusion: Our developed heating method (protocol IV) is very effective, reliable, simple, fast, and cheap compared to the other protocols in our study.
Ichthyoplankton is the cluster of planktonic organisms that consists of fish eggs and larvae. These planktonic stages belong to the temporary zooplankton, representing future exploitable stocks. The study of the early ontogenesis of fish plays a key role in the understanding and evaluation of these populations through the study of their abundance and their spatio-temporal distribution. To better understand and protect these fisheries resources, it is essential to identify the different stages of fish embryonic development. This identification is usually performed using the classical method, based on morphological criteria under a binocular magnifying glass; however, this methodology is not always sufficient and is time consuming and, therefore, it is necessary to rely increasingly on molecular tools. The major problem with these tools is the yield and quality of the nucleic acids extracted from ichthyoplankton, especially in the case of eggs, which are small. Several methods have been used for DNA extraction from ichthyoplankton, either automated or manual, but very often from larvae or adults. In the present work, five fish egg DNA extraction protocols were compared based on their DNA yield and extraction quality, verified by agarose gel electrophoresis and quantitative PCR amplification. The results showed that extraction by our heat-protocol for direct PCR (Hp-dPCR) presents the simplest and cheapest protocol of all the kits used in this study, providing a sufficient quantity and quality of nucleic acids to be used for PCR amplification, and being within the reach of third world laboratories that often do not have sufficiently large budgets to obtain automated kits.
The Medical diagnostic process requires more various methods to cover all sorts of clinical demands. Those methods depend on the types of samples and the requested analysis. The Medical diagnostic is considered as a process until making a clinical decision about a physiopathology or infection through medicals analysis. Nucleic acid amplification methods continue to play a role in these medicals analysis processes, but, many gold conventional standard Methods are time-consumers, less sensitive, technically challenging. It is that reason why recently, after the development of the PCR technique; the real-time PCR became a frequently requested tool to diagnose the virus, bacteria, fungal and parasites infections in different pathologies, especially in developed countries. However, its availability remains a big problem in resource-limited countries like Africa continent. It is because of the issue due to cost, technology, human resource constraints and the remote areas with limited access to laboratory facilities which stays also a major problem. Nucleic acids amplification methods remain to be expensive, not accessible for all laboratories. In addition to this, they are easily inhibited and contaminated by the other biochemical reagents time-consumer, for this reason, other methods of nucleic acid amplification under isothermal conditions have emerged each with its particularities. Despite their successes, molecular biology should have a method that combines many of the advantages and accessible everywhere. So, in 2000, the LAMP method was developed and offered many advantages such as speed, specificity, high sensitivity and the cost of very low equipment. In this review, we present the different studies to confirm the advantages of LAMP that we consider as an alternative to PCR in molecular diagnostics with a wide range of use on clinical samples and in scientific research and also, the method to save the Africans patients from the high cost and time consuming of other amplification methods.
CoViD-19 pandemic is a viral disease caused by SARS-COV-2virus and since December 2019, has spread rapidly in all the world countries; At the end of June 2020, over 10 million peoples were infected in the world and more than 500,000 deaths have been identified. Due to its fast transmission, the unavailability of drugs and vaccines and the asymptomatic patients who still spread the virus various measures were implemented to stop this virus. The studies were carried out to identify the molecular characteristics, transmission methods, origins, and all other clinical parameters necessary to eradicate it. The results have shown that CoViD-19 can be transmitted either animal-to-person or person-to-person by airborne. On March 11, 2020, world health organization (WHO) declared the CoViD-19 a pandemic, there, every concerned country has made the different health measures to stop the virus spread; the confirmed CoViD-19 patient undergoes the validation medicals diagnostics tests to follow specific treatments as time goes staying in quarantine room of the hospital to keep away from contact with others. To treat this pandemic, the world of medicine has tried with previous treatments of other viruses with encouraging results but of course, with doubts about the success of the therapeutic effectiveness and the scientific researches continue until the development of the therapeutic medicine and the Covid-19 specific vaccine. Today, the use of anti-inflammatory drugs was reported like chloroquine/hydroxychloroquine, the antiviral drugs like ritonavir, Lopinavir, ribavirin, and remdesivir and also the glycocorticoids hormones like dexaméthasone to the patients with severe CoViD-19. Different strains of this coronavirus infect humans, bats, and other mammals. Two strains of VOC-SARS have caused outbreaks of severe respiratory disease in humans: VOC-SARS, which caused an outbreak of severe acute respiratory syndrome (SARS) between 2002 and 2003, and VOC-SARS-2, which since late 2019 has caused a coronavirus disease pandemic 2019 (COVID-19). Even if today, there are not validated CoViD-19 drugs or vaccines. In This paper, we will talk about what we know until today on SARS-COV-2 and CoViD-19 pandemic particularly the clinical symptoms, transmissions ways, biological samples concerned by SARS-COV-2 infection, medicals laboratories parameters in CoViD-19 cases, medication and medicine and molecular diagnostics methods.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.