Corn Oligopeptide Alleviates Nonalcoholic Fatty Liver Disease by Regulating the Sirtuin Signaling Pathway.

Nonalcoholic fatty liver disease (NAFLD) represents the most prevalent type of chronic liver disease, spanning from simple steatosis to nonalcoholic steatohepatitis (NASH). Corn oligopeptide (CP) is a functional peptide known for its diverse pharmacological effects on metabolism. In this study, we evaluated the protective activity of CP against fatty liver disease. Oral administration of CP significantly reduced body weight gain by 2.95%, serum cholesterol by 22.54%, and liver injury, as evidenced by a reduction of 32.19% in serum aspartate aminotransferase (AST) and 49.10% in alanine aminotransferase (ALT) levels in mice subjected to a high-fat diet (HFD). In a streptozotocin/HFD-induced NASH mouse model, CP attenuated body weight gain by 5.11%, liver injury (with a 34.15% decrease in AST and 11.43% decrease in ALT), and, to some extent, liver inflammation and fibrosis. Proteomic analysis revealed the modulation of oxidative phosphorylation and sirtuin (SIRT) signaling pathways by CP. Remarkably, CP selectively inhibited the hepatic expression of mitochondrial SIRT3 and SIRT5 in both HFD and NASH models. In summary, CP demonstrates a preventive effect against metabolic-stress-induced NAFLD progression by modulating oxidative stress and the SIRT signaling pathway, suggesting the potential of CP as a therapeutic agent for the treatment of NAFLD and advanced-stage NASH.

Feasibility, efficiency & effectiveness of pooled sample testing strategy (pooled NAAT) for molecular testing of COVID-19.

BACKGROUND & OBJECTIVES: During the current COVID-19 pandemic, a large number of clinical samples were tested by real-time PCR. Pooling the clinical samples before testing can be a good cost-saving and rapid alternative for screening large populations. The aim of this study was to compare the performance characteristics, feasibility and effectiveness of pooling nasal swab and throat swab samples for screening and diagnosis of SARS-CoV-2. METHODS: The pool testing was applied on a set of samples coming from low COVID-19 positivity areas. A total of 2410 samples were tested in pools of five samples each. A total of five pools of five samples each were generated and tested for E gene. RESULTS: Of the total of 482 pools (2410 samples) 24 pools flagged positive. Later on pool de-convolution, a total of 26 samples were detected as positive for COVID-19, leading to positivity of about one per cent in the test population. For the diagnosis of individual samples, the pooling strategies resulted in cost savings of 75 per cent (5 samples per pool). INTERPRETATION & CONCLUSIONS: It was observed that testing samples for COVID-19 by reverse transcription (RT)- PCR after pooling could be a cost-effective method which would save both in manpower and cost especially for resource-poor countries and at a time when test kits were short in supply.

SARS-CoV-2 -RNA persists longer in faecal sample as compared to nasal and throat swab samples of COVID-19 patients'; an observational study.

The route of transmission of Novel SARS-CoV-2 virus is ambiguous. In this regard we planned a study to find out SARS-CoV-RNA shedding in various clinical samples of 9 COVID-19 positive patients. SARS-CoV-RNA was detected in nasal swab (NS), throat swab (TS) and faecal sample but was not detected in serum and urine samples. We also report that SARS-CoV-2-RNA persisted in faeces for >20 days. Persistence of faecal RNA might impose challenge in infection control and the disease may spread to household contacts if discharged. Perineal cleaning and hygiene may be advised at the time of vaginal delivery.

Human parvovirus 4: An emerging etiological agent in cases presenting with influenza like illness.

This study was planned to study the association of parvovirus 4 (PARV4) with Influenza-like illness (ILI). A total of 1111 patients with a clinical diagnosis of ILI and 220 healthy controls were tested for Influenza A/HINI/and H3N2, Influenza B, and PARV4. Further sequencing was done to analyze the genotype distribution of parvovirus 4. Influenza A/HINI, A/H3N2, and B were detected in 334 (30.06%), 9 (0.81%), and 10 (0.9%) cases respectively. PARV4 was detected in 135 (12.15%) cases and one healthy control. Parvovirus 4 was significantly higher in cases as compared to controls (relative risk, 30.77%; p < .0006). Sequencing of 20 isolates suggests the dominance of genotype 2 in our region.

Pooled testing for COVID-19 diagnosis by real-time RT-PCR: A multi-site comparative evaluation of 5- & 10-sample pooling.

BACKGROUND & OBJECTIVES: Public health and diagnostic laboratories are facing huge sample loads for COVID-19 diagnosis by real-time reverse transcription-polymerase chain reaction (RT-PCR). High sensitivity of optimized real-time RT-PCR assays makes pooled testing a potentially efficient strategy for resource utilization when positivity rates for particular regions or groups of individuals are low. We report here a comparative analysis of pooled testing for 5- and 10-sample pools by real-time RT-PCR across 10 COVID-19 testing laboratories in India. METHODS: Ten virus research and diagnostic laboratories (VRDLs) testing for COVID-19 by real-time RT-PCR participated in this evaluation. At each laboratory, 100 nasopharyngeal swab samples including 10 positive samples were used to create 5- and 10-sample pools with one positive sample in each pool. RNA extraction and real-time RT-PCR for SARS-CoV-2-specific E gene target were performed for individual positive samples as well as pooled samples. Concordance between individual sample testing and testing in the 5- or 10-sample pools was calculated, and the variation across sites and by sample cycle threshold (Ct) values was analyzed. RESULTS: A total of 110 each of 5- and 10-sample pools were evaluated. Concordance between the 5-sample pool and individual sample testing was 100 per cent in the Ct value ≤30 cycles and 95.5 per cent for Ctvalues ≤33 cycles. Overall concordance between the 5-sample pooled and individual sample testing was 88 per cent while that between 10-sample pool and individual sample testing was 66 per cent. Although the concordance rates for both the 5- and 10-sample pooled testing varied across laboratories, yet for samples with Ct values ≤33 cycles, the concordance was ≥90 per cent across all laboratories for the 5-sample pools. INTERPRETATION & CONCLUSIONS: Results from this multi-site assessment suggest that pooling five samples for SARS-CoV-2 detection by real-time RT-PCR may be an acceptable strategy without much loss of sensitivity even for low viral loads, while with 10-sample pools, there may be considerably higher numbers of false negatives. However, testing laboratories should perform validations with the specific RNA extraction and RT-PCR kits in use at their centres before initiating pooled testing.

Human Parvovirus 4: A harmless bystander or a pathogen of severe acute respiratory illness.

INTRODUCTION: Severe Acute Respiratory Infection (SARI) is an important cause of morbidity and mortality worldwide, caused by a large number of viral and bacterial agents. PARV4 is a recently identified virus detected in human blood and variety of tissues, but its disease association with SARI could not be established. OBJECTIVE: In the present case control study, we aim to investigate the association of PARV4 with SARI. METHODS: The Nasal and Throat swab (NS/TS) samples of 241 cases and 146 healthy controls were tested for most common respiratory viruses and PARV4 by real-time PCR. RESULTS: PARV4 was detected in 64(26.55%) SARI cases and only one healthy control (0.68%). PARV4 was the most common viral agent detected in SARI cases. A strong association of PARV4 is seen with severe respiratory illness. CONCLUSION: Detection of PARV4 in a significantly higher number of SARI cases, in comparison with controls, suggests association of PARV4 with SARI. PARV4 genotype 2 is the only circulating strain detected in our study.