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Modified bisanthraquinones are complex dimeric natural products containing a cage-like structural motif. For their biosynthesis, monomeric dihydroanthraquinones have been proposed as key intermediates despite not being isolated from natural sources or synthesized as of yet. Here, isolation and characterization of dihydroemodin, as well as dihydrolunatin, synthesized by a biomimetic and chemoenzymatic approach using NADPH-dependent polyhydroxyanthracence reductase (PHAR) from Cochliobolus lunatus followed by Pb(OAc) oxidation is reported. Subsequent dimerization through a hetero-Diels-Alder reaction of the dihydroemodin and dihydrolunatin resulted in (-)-flavoskyrin (68 %) and (-)-lunaskyrin (62 %), respectively. Pyridine treatment of (-)-flavoskyrin and (-)-lunaskyrin gave (-)-rugulosin and (-)-2,2'-epi-cytoskyrin A in 64 % and 60 % yield, respectively, through a cascade that involves two dimeric intermediates. Implications of the described synthesis for the biosynthesis of bisanthraquinones by a combination of enzymatic and spontaneous steps are discussed.

Screening of blood and blood products is important to reduce the risk of transfusion transmitted infections (TTIs). The transfusion of unscreened or inadequately screened blood and blood products are the major source of TTIs. The aim of this paper is to find out the prevalence of TTIs in ABO blood groups and Rh type system. A total of 4128 blood donors were screened from January 2010 to April 2014. Serological tests were performed for hepatitis B surface antigen (HBsAg), anti hepatitis C virus (Anti-HCV), anti HIV-1 and 2, venereal disease research Laboratory test (VDRL) and malaria parasite (MP) antigen. In seroreactive donors, HBsAg, Anti-HCV, VDRL, MP antigen and anti HIV were positive in 40 cases, 26 cases, 19 cases, 6 cases and 2 cases, respectively. Highest percentage of HBsAg, Anti HCV, VDRL, MP antigen and anti HIV was observed in blood group A negative (2/50), O negative (1/66), B negative (1/91), AB positive (2/377) blood group respectively. In the present study, the total number of Rhnegative donors is lower when compared to Rh-positive blood donors, but Rh-negative blood donors show higher percentages of seroreactivity for TTIs. Larger scale studies at molecular level are required to improve the knowledge of this aspect.

17β-Hydroxysteroid dehydrogenase (17β-HSDcl) from the filamentous fungus Curvularia lunata (teleomorph Cochliobolus lunatus) catalyzes NADP(H)-dependent oxidoreductions of androgens and estrogens. Despite detailed biochemical and structural characterization of 17β-HSDcl, its physiological function remains unknown. On the basis of amino acid sequence alignment, phylogenetic studies, and the recent identification of the physiological substrates of the homologous MdpC from Aspergillus nidulans and AflM from Aspergillus parasiticus, we propose an anthrahydroquinone as the physiological substrate of 17β-HSDcl. This is also supported by our analysis of a secondary metabolite biosynthetic gene cluster in C. lunata m118, containing 17β-HSDcl and ten other genes, including a polyketide synthase probably involved in emodin formation. Chemoenzymatic reduction of emodin by 17β-HSDcl in the presence of sodium dithionite verified this hypothesis. On the basis of these results, the involvement of a 17β-HSDcl in the biosynthesis of other anthrahydroquinone-derived natural products is proposed; hence, 17β-HSDcl should be more appropriately referred to as a polyhydroxyanthracene reductase (PHAR).

An NADPH-dependent oxidoreductase from Talaromyces islandicus WF-38-12, identified through genome analysis, catalyzes the regio- and enantioselective reduction of substituted anthrols.

Covid-19 pandemic has affected the whole word medically, economically and emotionally. It is being considered as the biggest pandemic after the Spanish flu, with very high degree of morbidity and mortality in those with complications. The diagnostic and treatment criteria of this novel virus are being updated frequently as nothing much is known about it. This highlights the importance of hematology lab parameters in Covid diagnosis and prediction of disease progression. Multiple studies on complete blood counts and it’s derived parameters have been conducted in patients of Covid-19 however limited literature is available which discusses the morphology of circulating blood cells in Covid-19 cases. This short communication is presented with the purpose of highlighting the peripheral blood findings of 50 lab confirmed Covid-19 cases admitted at Super Specialty Pediatric Hospital and Post Graduate Teaching Hospital, NOIDA.

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The cases of three young children (mean age 5.8 years) in whom fulminant hepatic failure and acute intravascular haemolysis were the presenting manifestations of Wilson's disease are reported. Although diagnosis was made ante-mortem and chelation therapy instituted, the course was relentlessly fatal in all three cases. This presentation of Wilson's disease at such a young age is noteworthy.