scholarly journals Screening for SARS-CoV-2 infections with colorimetric RT-LAMP and LAMP sequencing

2020 ◽  
Author(s):  
Viet Loan Dao Thi ◽  
Konrad Herbst ◽  
Kathleen Boerner ◽  
Matthias Meurer ◽  
Lukas PM Kremer ◽  
...  
Keyword(s):  
Public Health Problem ◽  
Lamp Assay ◽  
Rna Isolation ◽  
Cycle Number ◽  
Clinical Patient ◽  
Viral Loads ◽  
Wide Range ◽  
Significant Public Health ◽  
Validation Procedure ◽  
Rapid Tests

AbstractThe COVID-19 pandemic caused by the novel SARS-CoV-2 virus poses a significant public-health problem. In order to control the pandemic, rapid tests for detecting existing infections and assessing virus spread are critical.Approaches to detect viral RNA based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) hold outstanding promise towards greatly simplified and broadly applicable testing methods. RT-LAMP assays appear more robust than qPCR-based methods and only require incubation at a constant temperature, thus eliminating the need for sophisticated instrumentation.Here, we tested a two-color RT-LAMP protocol using clinical SARS-CoV-2 samples and also established a protocol that does not require prior RNA isolation (“swab-to-RT-LAMP”). Our study is based on several hundred clinical patient samples with a wide range of viral loads, thus allowing, for the first time, to accurately determine the sensitivity and specificity of the RT-LAMP assay for the detection of SARS-CoV-2 in patients. We found that RT-LAMP can reliably detect SARS-CoV-2 samples with a qPCR threshold cycle number (CT value) of up to 30 in the standard RT-qPCR assay. We used both, either purified RNA or direct pharyngeal swab specimens and showed that RT-LAMP assays have, despite a decreased sensitivity compared to RT-qPCR, excellent specificity. We also developed a multiplexed LAMP-sequencing protocol as a diagnostic and validation procedure to detect and record the outcome of RT-LAMP assays. LAMP-sequencing is fully scalable and can assess the results of thousands of LAMP reactions in parallel. Finally, we propose applications of RT-LAMP based assays for SARS-CoV-2 detection.

scholarly journals A colorimetric RT-LAMP assay and LAMP-sequencing for detecting SARS-CoV-2 RNA in clinical samples

2020 ◽  
Vol 12 (556) ◽  
pp. eabc7075 ◽  
Author(s):  
Viet Loan Dao Thi ◽  
Konrad Herbst ◽  
Kathleen Boerner ◽  
Matthias Meurer ◽  
Lukas PM Kremer ◽  
...  
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Lamp Assay ◽  
Rna Isolation ◽  
Viral Rna ◽  
Clinical Samples ◽  
Lower Sensitivity ◽  
Ct Number ◽  
Critical Approaches ◽  
Validation Procedure ◽  
Rapid Tests

The coronavirus disease 2019 (COVID-19) pandemic caused by the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) coronavirus is a major public health challenge. Rapid tests for detecting existing SARS-CoV-2 infections and assessing virus spread are critical. Approaches to detect viral RNA based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) have potential as simple, scalable, and broadly applicable testing methods. Compared to RT quantitative polymerase chain reaction (RT-qPCR)–based methods, RT-LAMP assays require incubation at a constant temperature, thus eliminating the need for sophisticated instrumentation. Here, we tested a two-color RT-LAMP assay protocol for detecting SARS-CoV-2 viral RNA using a primer set specific for the N gene. We tested our RT-LAMP assay on surplus RNA samples isolated from 768 pharyngeal swab specimens collected from individuals being tested for COVID-19. We determined the sensitivity and specificity of the RT-LAMP assay for detecting SARS-CoV-2 viral RNA. Compared to an RT-qPCR assay using a sensitive primer set, we found that the RT-LAMP assay reliably detected SARS-CoV-2 RNA with an RT-qPCR cycle threshold (CT) number of up to 30, with a sensitivity of 97.5% and a specificity of 99.7%. We also developed a swab–to–RT-LAMP assay that did not require a prior RNA isolation step, which retained excellent specificity (99.5%) but showed lower sensitivity (86% for CT < 30) than the RT-LAMP assay. In addition, we developed a multiplexed sequencing protocol (LAMP-sequencing) as a diagnostic validation procedure to detect and record the outcome of RT-LAMP reactions.

scholarly journals Hepatitis E: an underestimated emerging threat

2019 ◽  
Vol 6 ◽  
pp. 204993611983716 ◽  
Author(s):  
Glynn W. Webb ◽  
Harry R. Dalton
Keyword(s):  
Burden Of Disease ◽  
Public Health Problem ◽  
Hepatitis E ◽  
Industrialized Countries ◽  
Zoonotic Infections ◽  
Wide Range ◽  
The World ◽  
Significant Public Health ◽  
History Of

Hepatitis E virus (HEV) is the most common cause of viral hepatitis in the world. It is estimated that millions of people are infected every year, resulting in tens of thousands of deaths. However, these estimates do not include industrialized regions and are based on studies which employ assays now known to have inferior sensitivity. As such, this is likely to represent a massive underestimate of the true global burden of disease. In the developing world, HEV causes large outbreaks and presents a significant public-health problem. Until recently HEV was thought to be uncommon in industrialized countries, and of little relevance to clinicians in these settings. We now know that this is incorrect, and that HEV is actually very common in developed regions. HEV has proved difficult to study in vitro, with reliable models only recently becoming available. Our understanding of the lifecycle of HEV is therefore incomplete. Routes of transmission vary by genotype and location: endemic regions experience large waterborne epidemics, while sporadic cases in industrialized regions are zoonotic infections likely spread via the food chain. Both acute and chronic infection has been observed, and a wide range of extrahepatic manifestations have been reported. This includes neurological, haematological and renal conditions. As the complete clinical phenotype of HEV infection is yet to be characterized, a large proportion of cases go unrecognized or misdiagnosed. In many cases HEV infection does not feature in the differential diagnosis due to a lack of knowledge and awareness of the disease amongst clinicians. In combination, these factors have contributed to an underestimation of the threat posed by HEV. Improvements are required in terms of recognition and diagnosis of HEV infection if we are to understand the natural history of the disease, improve management and reduce the burden of disease around the world.

scholarly journals Comparative sensitivity evaluation for 122 CE-marked SARS-CoV-2 antigen rapid tests

2021 ◽  
Author(s):  
Heinrich Scheiblauer ◽  
Angela Filomena ◽  
Andreas Nitsche ◽  
Andreas Puyskens ◽  
Victor Corman ◽  
...  
Keyword(s):  
Market Access ◽  
High Sensitivity ◽  
Lower Sensitivity ◽  
Viral Loads ◽  
Sensitivity Evaluation ◽  
Independent Evaluation ◽  
Wide Range ◽  
German Healthcare System ◽  
Rapid Tests ◽  
Minimum Sensitivity

Abstract Objective Independent evaluation of the sensitivity of CE-marked SARS-CoV-2 antigen rapid diagnostic tests (Ag RDT) offered in Germany. Method The sensitivity of 122 Ag RDT was adressed using a common evaluation panel. Minimum sensitivity of 75% for panel members with CT<25 was used for differentiation of devices eligible for reimbursement in in the German healthcare system. Results The sensitivity of different SARS-CoV-2 Ag RDT varied over a wide range. The sensitivity limit of 75% for panel members with CT <25 was met by 96 of the 122 tests evaluated; 26 tests exhibited lower sensitivity, few of which were completely failing. Some devices exhibited high sensitivity, e.g. 100% for CT<30. Conclusion This comparative evaluation succeeded to distinguish less sensitive from better performing Ag RDT. Most of the Ag RDT evaluated appear to be suitable for fast identification of acute infections associated with high viral loads. Market access of SARS-CoV-2 Ag RDT should be based on minimal requirements for sensitivity and specificity.

scholarly journals Kynurenines as a Novel Target for the Treatment of Malignancies

2021 ◽  
Vol 14 (7) ◽  
pp. 606
Author(s):  
Adrian Mor ◽  
Anna Tankiewicz-Kwedlo ◽  
Dariusz Pawlak
Keyword(s):  
Public Health Problem ◽  
Modern Medicine ◽  
Kynurenine Pathway ◽  
System Response ◽  
Neoplastic Progression ◽  
Wide Range ◽  
Significant Public Health ◽  
Tryptophan Metabolites ◽  
Effective Therapeutic Strategy ◽  
Novel Target

Malignancies are unquestionably a significant public health problem. Their effective treatment is still a big challenge for modern medicine. Tumors have developed a wide range of mechanisms to evade an immune and therapeutic response. As a result, there is an unmet clinical need for research on solutions aimed at overcoming this problem. An accumulation of tryptophan metabolites belonging to the kynurenine pathway can enhance neoplastic progression because it causes the suppression of immune system response against cancer cells. They are also involved in the development of the mechanisms responsible for the resistance to antitumor therapy. Kynurenine belongs to the most potent immunosuppressive metabolites of this pathway and has a significant impact on the development of malignancies. This fact prompted researchers to assess whether targeting the enzymes responsible for its synthesis could be an effective therapeutic strategy for various cancers. To date, numerous studies, both preclinical and clinical, have been conducted on this topic, especially regarding the inhibition of indoleamine 2,3-dioxygenase activity and their results can be considered noteworthy. This review gathers and systematizes the knowledge about the role of the kynurenine pathway in neoplastic progression and the findings regarding the usefulness of modulating its activity in anticancer therapy.

scholarly journals A Research Synthesis of Therapeutic Interventions for Whiplash-Associated Disorder (WAD): Part 5 – Surgical and Injection-Based Interventions for Chronic WAD

2010 ◽  
Vol 15 (5) ◽  
pp. 323-334 ◽  
Author(s):  
Robert W Teasell ◽  
J Andrew McClure ◽  
David Walton ◽  
Jason Pretty ◽  
Katherine Salter ◽  
...  
Keyword(s):  
Controlled Trial ◽  
Chronic Phase ◽  
Public Health Problem ◽  
Therapeutic Interventions ◽  
Radiofrequency Neurotomy ◽  
Wide Range ◽  
Significant Public Health ◽  
Contradictory Evidence ◽  
Evidence Database ◽  
Whiplash Associated Disorder

Whiplash-associated disorder (WAD) represents a significant public health problem, resulting in substantial social and economic costs throughout the industrialized world. While many treatments have been advocated for patients with WAD, scientific support regarding their effectiveness is often lacking. A systematic review was conducted to evaluate the strength of evidence associated with various WAD therapies. Multiple databases (including Web of Science, EMBASE and PubMed) were searched to identify all studies published from January 1980 through March 2009 that evaluated the effectiveness of any well-defined treatment for acute (less than two weeks), subacute (two to 12 weeks) or chronic (more than 12 weeks) WAD. The present article, the fifth in a five-part series, evaluates the evidence for surgical and injection-based interventions initiated during the chronic phase of WAD. Twenty-five studies were identified that met the inclusion criteria, six of which were randomized controlled trials with ‘good’ overall methodological quality (median Physiotherapy Evidence Database score of 7.5). For the treatment of chronic WAD, there was moderate evidence supporting radiofrequency neurotomy as an effective treatment for whiplash-related pain, although relief is not permanent. Sterile water injections have been demonstrated to be superior to saline injections; however, it is not clear whether this treatment is actually beneficial. There was evidence supporting a wide range of other interventions (eg, carpal tunnel decompression) with each of these evaluated by a single nonrandomized controlled trial. There is contradictory evidence regarding the effectiveness of botulinum toxin injections, and cervical discectomy and fusion. The evidence is not yet strong enough to establish the effectiveness of any of these treatments; of all the invasive interventions for chronic WAD, radiofrequency neurotomy appears to be supported by the strongest evidence. Further research is required to determine the efficacy and the role of invasive interventions in the treatment of chronic WAD.

scholarly journals A Fatal and Rare Case of Hydatid Cyst in the Pouch of Douglas

2021 ◽  
Author(s):  
Ritu Asnani ◽  
Sunil Kumar Yeshvanth ◽  
Lancelot Lobo ◽  
Shipra Sonkusare
Keyword(s):  
Hydatid Cyst ◽  
Rare Case ◽  
Frozen Section ◽  
Public Health Problem ◽  
Zoonotic Infection ◽  
Middle Income ◽  
Middle Income Countries ◽  
Significant Public Health Problem ◽  
Significant Public Health ◽  
Pouch Of Douglas

Abstract Hydatid cyst is a zoonotic infection and a significant public health problem in low- and middle-income countries. A 79-year-old female patient was presented to the gynecology outpatient department with complaints of pain in the abdomen and difficulty in micturition, with a mass palpable per speculum. The ultrasound was suggestive of an ovarian cystadenocarcinoma, whereas computed tomography of the abdomen favored hydatid cyst with adnexal neoplasm as a differential diagnosis. Considering the contradictory findings, a frozen section was sent to confirm the diagnosis, which showed hooklets of Echinococcus granulosus/hydatid cyst under the microscope. This was a rare case of pelvic hydatid cyst mimicking ovarian malignancy and was associated with a less-preferred mode of investigation (frozen section). This article focuses on how a frozen section, despite its limitations and being expensive, can still be considered for accurate patient management.

Possible role of Unani Pharmacology in COVID-19 – a narrative review

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Md Anzar Alam ◽  
Mohd Abdul Gani ◽  
G. Shama ◽  
Ghulamuddin Sofi ◽  
Mohd Aleemuddin Quamri
Keyword(s):  
Clinical Manifestations ◽  
Public Health Problem ◽  
World Health ◽  
Santalum Album ◽  
Boswellia Serrata ◽  
Unani Medicine ◽  
Significant Public Health Problem ◽  
Significant Public Health ◽  
Novel Coronavirus ◽  
Health Organization

AbstractAccording to the World Health Organization (WHO), viral diseases continue to rise, and pose a significant public health problem. Novel coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2. The pathogenesis and clinical manifestations of COVID-19 is close to Amraz-e-Wabai (epidemic diseases) which was described by Hippocrates, Galen, Aristotle, Razes, Haly Abbas, Avicenna, Jurjani etc. Presently, there is no specific or challenging treatment available for COVID-19. Renowned Unani Scholars recommended during epidemic situation to stay at home, and fumigate the shelters with aromatics herbs like Ood kham (Aquilaria agallocha Roxb.), Kundur (Boswellia serrata Roxb), Kafoor (Cinnamomum camphora L.), Sandal (Santalum album L), Hing (Ferula foetida L.) etc. Use of specific Unani formulations are claimed effective for the management of such epidemic or pandemic situation like antidotes (Tiryaqe Wabai, Tiryaqe Arba, Tiryaqe Azam, Gile Armani), Herbal Decoction (Joshandah), along with Sharbate Khaksi, Habbe Bukhar, Sharbate Zanjabeel, Khamira Marwareed, Jawarish Jalinus, and Sirka (vinegar). Such drugs are claimed for use as antioxidant, immunomodulatory, cardiotonic, and general tonic actions. The study enumerates the literature regarding management of epidemics in Unani medicine and attempts to look the same in the perspective of COVID-19 prevention and management.

scholarly journals Self-harm among in-school and street-connected adolescents in Ghana: a cross-sectional survey in the Greater Accra region

BMJ Open ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. e041609
Author(s):  
Emmanuel Nii-Boye Quarshie ◽  
Farag Shuweihdi ◽  
Mitch Waterman ◽  
Allan House
Keyword(s):  
Public Health Problem ◽  
Self Report ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Self Injury ◽  
Significant Public Health Problem ◽  
Significant Public Health ◽  
Treatment Measures ◽  
Self Harm ◽  
Greater Accra Region

ObjectivesTo identify the prevalence, methods, associations and reported reasons for self-harm among in-school and street-connected adolescents in Ghana.DesignA cross-sectional survey. We applied multi-level regression models and model-based cluster analysis to the data.SettingThree contexts in the Greater Accra region were used: second cycle schools, facilities of charity organisations and street census enumeration areas (sleeping places of street-connected adolescents, street corners, quiet spots of restaurants, markets, train and bus stations, and lorry and car parks).ParticipantsA regionally representative sample of 2107 (1723 in-school and 384 street-connected) adolescents aged 13–21 years.Outcome measuresParticipants responded to a structured self-report anonymous questionnaire describing their experience of self-harm and eliciting demographic information and social and personal adversities.ResultsThe lifetime prevalence of self-harm was 20.2% (95% CI 19.0% to 22.0%), 12-month prevalence was 16.6% (95% CI 15.0% to 18.0%) and 1-month prevalence was 3.1% (95% CI 2.0% to 4.0%). Self-injury alone accounted for 54.5% episodes and self-poisoning alone for 16.2% episodes, with more than one method used in 26% of episodes. Self-cutting (38.7%) was the most common form of self-injury, whereas alcohol (39.2%) and medications (27.7%) were the most commonly reported means of self-poisoning. The factors associated with self-harm were interpersonal: conflict with parents (adjusted OR (aOR)=1.87, 95% CI 1.24 to 2.81), physical abuse victimisation (aOR=1.69, 95% CI 1.16 to 2.47), difficulty in making and keeping friends (aOR=1.24, 95% CI 0.85 to 1.80), sexual abuse victimisation (aOR=1.21, 95% CI 0.78 to 1.87) and conflict between parents (aOR=1.07, 95% CI 0.73 to 1.56).ConclusionsSelf-harm is a significant public health problem among in-school and street-connected adolescents in the Greater Accra region of Ghana. Its origins are very largely in social and familial adversity, and therefore prevention and treatment measures need to be focused in these areas.

scholarly journals Noncompaction Cardiomyopathy—History and Current Knowledge for Clinical Practice

2021 ◽  
Vol 10 (11) ◽  
pp. 2457
Author(s):  
Birgit J. Gerecke ◽  
Rolf Engberding
Keyword(s):  
Clinical Practice ◽  
Current Knowledge ◽  
Clinical Manifestations ◽  
Clinical Patient ◽  
Noncompaction Cardiomyopathy ◽  
The Past ◽  
Wide Range ◽  
Morphological Variants ◽  
A Current ◽  
Healthy Persons

Noncompaction cardiomyopathy (NCCM) has gained increasing attention over the past twenty years, but in daily clinical practice NCCM is still rarely considered. So far, there are no generally accepted diagnostic criteria and some groups even refuse to acknowledge it as a distinct cardiomyopathy, and grade it as a variant of dilated cardiomyopathy or a morphological trait of different conditions. A wide range of morphological variants have been observed even in healthy persons, suggesting that pathologic remodeling and physiologic adaptation have to be differentiated in cases where this spongy myocardial pattern is encountered. Recent studies have uncovered numerous new pathogenetic and pathophysiologic aspects of this elusive cardiomyopathy, but a current summary and evaluation of clinical patient management are still lacking, especially to avoid mis- and overdiagnosis. Addressing this issue, this article provides an up to date overview of the current knowledge in classification, pathogenesis, pathophysiology, epidemiology, clinical manifestations and diagnostic evaluation, including genetic testing, treatment and prognosis of NCCM.

scholarly journals Direct detection of SARS-CoV-2 using non-commercial RT-LAMP reagents on heat-inactivated samples

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alisa Alekseenko ◽  
Donal Barrett ◽  
Yerma Pareja-Sanchez ◽  
Rebecca J. Howard ◽  
Emilia Strandback ◽  
...  
Keyword(s):  
Large Scale ◽  
Direct Detection ◽  
Dna Polymerases ◽  
Scale Up ◽  
Lamp Assay ◽  
Cost Effective ◽  
Reaction Conditions ◽  
Clinical Patient ◽  
Reverse Transcriptases ◽  
Large Scale Testing

AbstractRT-LAMP detection of SARS-CoV-2 has been shown to be a valuable approach to scale up COVID-19 diagnostics and thus contribute to limiting the spread of the disease. Here we present the optimization of highly cost-effective in-house produced enzymes, and we benchmark their performance against commercial alternatives. We explore the compatibility between multiple DNA polymerases with high strand-displacement activity and thermostable reverse transcriptases required for RT-LAMP. We optimize reaction conditions and demonstrate their applicability using both synthetic RNA and clinical patient samples. Finally, we validate the optimized RT-LAMP assay for the detection of SARS-CoV-2 in unextracted heat-inactivated nasopharyngeal samples from 184 patients. We anticipate that optimized and affordable reagents for RT-LAMP will facilitate the expansion of SARS-CoV-2 testing globally, especially in sites and settings where the need for large scale testing cannot be met by commercial alternatives.

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