Comparative effects of trichothecene mycotoxins on bovine platelet function: Acetyl T-2 toxin,a more potent inhibitor than T-2 toxin

The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10^?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.     

血管活性肠多肽结合核苷酸性质的研究

采用光亲和技术检测了血管活性肠多肽(VIP)与核苷酸之间的相互作用,发现VIP可以特异性结合同位素标记的GTP,还发现未标记的GTP以及其它三磷酸核苷抑制这种结合,这意味着VIP与上述三磷酸核苷之间的结合是一种典型的可逆性的结合反应.发现低浓度的GDP,GMP不但不抑制VIP与同位素标记GTP的结合反应,反而增强这种结合.联系到其它研究者关于GTP影响VIP与其受体结合反应的结果,可认为VIP能可逆性地连接一种三磷酸核苷,这种连接受反应系统中不同核苷酸比例影响,通过这种连接来调节VIP与其受体之间的反应.     

An extensive review on antifungal approaches in the treatment of mucormycosis

During the period of COVID-19, the occurrences of mucormycosis in immunocompromised patients have increased significantly. Mucormycosis (black fungus) is a rare and rapidly progressing fungal infection associated with high mortality and morbidity in India as well as globally. The causative agents for this infection are collectively called mucoromycetes which are the members of the order Mucorales. The diagnosis of the infection needs to be performed as soon as the occurrence of clinical symptoms which differs with types of Mucorales infection. Imaging techniques magnetic resonance imaging or computed tomography scan, culture testing, and microscopy are the approaches for the diagnosis. After the diagnosis of the infection is confirmed, rapid action is needed for the treatment in the form of antifungal therapy or surgery depending upon the severity of the infection. Delaying in treatment declines the chances of survival. In antifungal therapy, there are two approaches first-line therapy (monotherapy) and combination therapy. Amphotericin B ( 1 ) and isavuconazole ( 2 ) are the drugs of choice for first-line therapy in the treatment of mucormycosis. Salvage therapy with posaconazole ( 3 ) and deferasirox ( 4 ) is another approach for patients who are not responsible for any other therapy. Adjunctive therapy is also used in the treatment of mucormycosis along with first-line therapy, which involves hyperbaric oxygen and cytokine therapy. There are some drugs like VT-1161 ( 5 ) and APX001A ( 6 ), Colistin, SCH 42427, and PC1244 that are under clinical trials. Despite all these approaches, none can be 100% successful in giving results. Therefore, new medications with favorable or little side effects are required for the treatment of mucormycosis.     

Symmetry and Cell Division in Raphid Diatoms

The development and final morphology of the valve in raphe-bearingdiatoms exhibit a cryptic lateral polarity, and hence two typesof frustule can be distinguished. In the cis type both valveshave the same orientation; in the trans type they have oppositeorientations. Examination of a variety of taxa suggests thatin all dividing raphid diatoms, both new valves have the sameorientation and so only three types of division are possible:cis; cis + cis, cis trans + trans, trans; cis+trans. The possessionof different combinations of these explains the observed ratiosof cis: trans in different taxa, viz all cis; 1: 2 cis: trans;and roughly 1: 1 cis: trans. The implications of the resultsfor diatom systematics are examined, with special referenceto Navicula Bory. Diatom systematic, diatom valve morphogenesis, cell symmetry, raphe structure     

Monoclonal antibodies to rabbit liver cytochrome P-448

Cytochrome P-448 (mol wt 55,000 Daltons) from rabbit liver was purified to a specific content of 16.6 nmol/mg. Mice were immunised with this preparation, their spleens removed and dissociated lymphocytes hybridised with myeloma cells. Four monoclonal antibodies against cytochrome P-448 were raised and partially characterised. All four antibodies interacted with cytochrome P-448 in intact microsomal fractions and selectively immunoadsorbed cytochrome P-448 from solubilised microsomal preparations. One of the antibodies inhibited benzo[a] pyrene hydroxylase activity in a reconstituted system, one had no effect on activity and two increased activity. The possible applications of such antibodies are discussed.