Virus Unit

Abstract An Au(III) complex, [Au(2‐ptp)2]Cl (1) (2‐ptp = 2‐(3‐phenyl‐1H‐1,2,4‐triazol‐5‐yl)pyridine), has been characterized by single‐crystal X‐ray diffraction technique and other spectroscopic data. Presence of different noncovalent interactions leads to the formation of 3D supramolecular structure. The complex 1 exhibits antibacterial activity against Gram‐positive (MIC) (Staphylococcus aureus [240 μg/ml], Bacillus subtilis [645 μg/ml]) and Gram‐negative (Escherichia coli [270 μg/ml], Enterococcus faecalis [820 μg/ml], Klebsiella pneumonia [785 μg/ml]) bacteria. Also, the toxicity of 1 has been checked by MTT assay. The complex shows promising anticancer activity against Vero cells and the CC50 is 405 μg/ml. The complex also shows improved conductivity (Λ) by one order difference on illumination (Λdark, 7.42 × 10−5 Sm−1 and Λillumination, 2.45 × 10−4 Sm−1).

BackgroundRegulatory T cells are known to play a key role to counter balance the protective immune response and immune mediated pathology. However, the role of naturally occurring regulatory cells CD4+CD25+Foxp3+ in malaria infection during the disease pathogenesis is controversial. Beside this, ICOS molecule has been shown to be involved in the development and function of regulatory T cell enhance IL-10 production. Therefore, possible involvement of the ICOS dependent regulatory CD4+ICOS+Foxp3+ T cells in resistance/susceptibility during malaria parasite is explored in this study.Methods5 × 105 red blood cells infected with non-lethal and lethal parasites were inoculated in female Balb/c mice by intra-peritoneal injection. Infected or uninfected mice were sacrificed at early (3rd day post infection) and later stage (10th day post infection) of infection. Harvested cells were analysed by using flow cytometer and serum cytokine by Bioplex assay.ResultsThin blood films show that percentages of parasitaemia increases with disease progression in infections with the lethal malaria parasite and mice eventually die by day 14th post-infection. Whereas in case of non-lethal malaria parasite, parasitaemia goes down by 7th day post infection and gets cleared within 13th day. The number of CD4+ ICOS+ T cells increases in lethal infection with disease progression. Surprisingly, in non-lethal parasite, ICOS expression decreases after day 7th post infection as parasitaemia goes down. The frequency of CD4+ICOS+FoxP3+ Tregs was significantly higher in lethal parasitic infection as compared to the non-lethal parasite. The level of IL-12 cytokine was remarkably higher in non-lethal infection compared to the lethal infection. In contrast, the level of IL-10 cytokines was higher in lethal parasite infection compared to the non-lethal parasite.ConclusionTaken together, these data suggest that lethal parasite induce immunosuppressive environment, protecting from host immune responses and help the parasite to survive whereas non-lethal parasite leads to low frequencies of Treg cells seldom impede immune response that allow the parasite to get self-resolved.Graphical

The clinical laboratory is playing an increasingly important role in the patient-centered approach to the delivery of health services. Early detection of the importation of COVID-19 is a crucial challenge for all countries at risk of importation from areas of active transmission. This article aims to share the experience of the IPCI in the optimum management of the pre-analytical phase related to diagnostic tests for COVID 19. From the start of the pandemic the state and the IPCI made several organizational decisions to respond effectively to all trends of the COVID 19 epidemic in our country. Outsourcing of pre-analysis with creation of several sections: preparation of tube kits, aliquoting of samples from patients suspected of COVID19, reception, sorting and decontamination. Exemplary use of administrative and laboratory support staff. Our findings should help establish urgent priorities for intensified preparedness and response support in specific African countries with moderate or high risk of COVID-19 importation and whose capacity to manage the health emergency is low relatively low.

A bio-inspired, self-healing chitosan-5-(benzo[d]thiazol-2-yl)-4-hydroxyisophthalaldehyde (CBTHP) fluorescent hydrogel has been developed which exhibits ultrafast ESIPT in both gel and solution phase.

Promyelocytic leukemia nuclear bodies (PML-NB) are sub-nuclear organelles that are the hub of numerous proteins. DNA/RNA viruses often hijack the cellular factors resident in PML-NBs to promote their proliferation in host cells. Hepatitis B virus (HBV), belonging to Hepadnaviridae family, remains undetected in early infection as it does not induce the innate immune response and is known to be the cause of several hepatic diseases leading to cirrhosis and hepatocellular carcinoma. The association of PML-NB proteins and HBV is being addressed in a number of recent studies. Here, we report that the PML-NB protein Speckled 110 kDa (Sp110) is SUMO1-modified and undergoes a deSUMOylation-driven release from the PML-NB in the presence of HBV. Intriguingly, Sp110 knockdown significantly reduced viral DNA load in the culture supernatant by activation of the type I interferon-response pathway. Furthermore, we found that Sp110 differentially regulates several direct target genes of hepatitis B virus protein X (HBx), a viral co-factor. Subsequently, we identified Sp110 as a novel interactor of HBx and found this association to be essential for the exit of Sp110 from the PML-NB during HBV infection and HBx recruitment on the promoter of these genes. HBx, in turn, modulates the recruitment of its associated transcription cofactors p300/HDAC1 to these co-regulated genes, thereby altering the host gene expression program in favor of viral persistence. Thus, we report a mechanism by which HBV can evade host immune response by hijacking the PML-NB protein Sp110, and therefore, we propose it to be a novel target for antiviral therapy.