Cinnamic Acid Bornyl Ester Derivatives from Valeriana wallichii Exhibit Antileishmanial In Vivo Activity in Leishmania major-Infected BALB/c Mice

Human leishmaniasis covers a broad spectrum of clinical manifestations ranging from self-healing cutaneous leishmaniasis to severe and lethal visceral leishmaniasis caused among other species by Leishmania major or Leishmania donovani, respectively. Some drug candidates are in clinical trials to substitute current therapies, which are facing emerging drug-resistance accompanied with serious side effects. Here, two cinnamic acid bornyl ester derivatives (1 and 2) were assessed for their antileishmanial activity. Good selectivity and antileishmanial activity of bornyl 3-phenylpropanoate (2) in vitro prompted the antileishmanial assessment in vivo. For this purpose, BALB/c mice were infected with Leishmania major promastigotes and treated with three doses of 50 mg/kg/day of compound 2. The treatment prevented the characteristic swelling at the site of infection and correlated with reduced parasite burden. Transmitted light microscopy and transmission electron microscopy of Leishmania major promastigotes revealed that compounds 1 and 2 induce mitochondrial swelling. Subsequent studies on Leishmania major promastigotes showed the loss of mitochondrial transmembrane potential (ΔΨ_m) as a putative mode of action. As the cinnamic acid bornyl ester derivatives 1 and 2 had exhibited antileishmanial activity in vitro, and compound 2 in Leishmania major-infected BALB/c mice in vivo, they can be regarded as possible lead structures for the development of new antileishmanial therapeutic approaches.     

Altered expression and editing of miRNA-100 regulates iTreg differentiation

RNA editing of miRNAs, especially in the seed region, adds another layer to miRNA mediated gene regulation which can modify its targets, altering cellular signaling involved in important processes such as differentiation. In this study, we have explored the role of miRNA editing in CD4⁺ T cell differentiation. CD4⁺ T cells are an integral component of the adaptive immune system. Naïve CD4⁺ T cells, on encountering an antigen, get differentiated either into inflammatory subtypes like Th1, Th2 or Th17, or into immunosuppressive subtype Treg, depending on the cytokine milieu. We found C-to-U editing at fifth position of mature miR-100, specifically in Treg. The C-to-U editing of miR-100 is functionally associated with at least one biologically relevant target change, from MTOR to SMAD2. Treg cell polarization by TGFβ1 was reduced by both edited and unedited miR-100 mimics, but percentage of Treg in PBMCs was only reduced by edited miR-100 mimics, suggesting a model in which de-repression of MTOR due to loss of unedited mir-100, promotes tolerogenic signaling, while gain of edited miR-100 represses SMAD2, thereby limiting the Treg. Such delicately counterbalanced systems are a hallmark of immune plasticity and we propose that miR-100 editing is a novel mechanism toward this end.     

Biochemical Changes in Nodules of Vigna mungo (L.) During Vegetative and Reproductive Stages of Plant Growth in the Field

Nitrogenase activity in root nodules of Vigna mungo L. attaineda peak at the flowering stage and declined thereafter. Levelsof soluble proteins, particularly leghaemoglobin, and ratesof protein and RNA synthesis declined with nitrogenase. Activitiesof protease and RNase increased with the ageing or nodules.Carbohydrate utilization, sugar levels and ATP were maximumat the early pod stage and gradually declined with age. Theseinterrelated changes point to a loss of nitrogenase activityas the first indicator of nodule senescence that is linked withflowering. Later, losses of proteins, total sugar and ATP wererelated to increased RNase and protease activity and decreasedhexokinase and to a loss in capacity to incorporate amino acidinto protein.Copyright 1993, 1999 Academic Press Vigna mungo (L.), senescene, nitrogenase, leghaemoglobin, field experiments     

Predominance of genomically defined A lineage of HPV16 over D lineage in Indian patients from eastern India with squamous cell carcinoma of the cervix in association with distinct oncogenic phenotypes

Human papillomavirus type-16 (HPV16) is classified into lineages, A, B, C and D and 10 sub-lineages portraying variable infectivity, persistence, and cytological outcomes, however, with geographical variations. Our objective was to delineate the distinctive features of lineages among cervical squamous cell carcinoma (SCC) in the eastern region of India. A total of 145 SCC cases and 24 non-malignant specimens, harboring episomal HPV16, were included. The presence of higher proportion of lineage A over D was observed among SCC cases (86.89% A1, 8.97% D1 and 4.14% D2), while only A1 sub-lineage viruses were found among control specimens. Among the A1 viruses, an association of variants in the E5 (Y44L, I65V), E6 (L83V) genes and LCR: C7577T with SCC, with combined Odd''s ratio (95% CI) of 20.5(4.61–91.25) was observed. Network analyses revealed the presence of 10 clades of lineage A viruses comprising of 64 HPV16 genomes harboring the risk alleles. High episomal HPV16 DNA copy numbers (adjusted p-value= 0.0271) and E7 mRNA expression (p-value=0.000017) predominated in SCC with lineage A, over D. Our study highlights the distinctive modalities of oncogenicity among different HPV16 lineages.     

A cDNA clone of the hnRNP C proteins and its homology with the single-stranded DNA binding protein UP2.

A cDNA clone which expresses a protein that cross-reacts immunologically with the human C1 and C2 hnRNP core proteins has been isolated. The clone was selected by a sensitive immunochemical assay employing an avidin-biotin complex for detection, and identified as a clone for the hnRNP C proteins by a highly sensitive antibody select assay that is described here. The clone contains 677 nucleotides, and, as shown by northern blotting, is derived from a 1.5 Kb poly(A)+ mRNA. There are regions of strong homology between the human and mouse genes, weak homology is seen with chicken DNA, and very little, if any, homology can be detected with Drosophila, Artemia, sea urchin, or yeast DNAs. Two peptides (a total of 24 amino acids) of the calf thymus single-stranded DNA binding protein UP2 show perfect homology with the deduced amino acid sequence of the clone, suggesting that UP2 is related to the hnRNP C proteins. There is also a region that has a sequence very similar to two regions of the single-stranded DNA binding protein UP1 that contain proposed DNA binding sites.     

Spectroscopic studies on the interaction of bilirubin with symmetrical alkyl diamines

The interactions of symmetrical alkyldiamines with bilirubin-IX α have been examined in dichloromethane and dioxane solutions, by visible region difference sPectroscoPy and florescence methods. In dioxane solutions a clear difference is observed between the comPlexes of the shorter chain diamines (number of sPacer methylene grouPs (n ≤4) ) and the longer chain diamines (n ≥6) . The variations in sPectral features with diamine chain length are less Pronounced in dichloromethane. The sPectroscoPic results are consistent with the occurrence of distinct bilirubin conformations dePending uPon the solvent and the geometry of the interacting recePtor. Based on molecular modelling two conformations are ProPosed. A ‘ridge-tile’ model similar to that observed in crystals is favoured for binding to the longer diamines, while a ‘quasi-cyclic’ structure is Preferred for interaction with the short chain diamines.     

Intracellular pH and oxygen chemoreception in the cat carotid body in vitro.

To test the hypothesis that O2 chemoreception in the carotid body (CB) is mediated by cellular acidosis, we simultaneously measured responses of the chemosensory and intracellular pH (pHi) to agents that are known to change pHi and studied the effects of hypoxia and ischemia on these variables in the cat CB. The CB was perfused and superfused in vitro with a modified Tyrode's solution at 36.0 +/- 0.5 degrees C with or without CO2-HCO3- (pH 7.40) and equilibrated at a given PO2. Chemosensory discharges were recorded from the whole carotid sinus nerve. To measure pHi changes, the CB was loaded with the pH-sensitive indicator 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein, and the fluorescence (excitation 420-490 nm, emission greater than 515 nm) was detected by an intensified charged coupled device camera with an epifluorescence macroscope. Boluses of Tyrode's solution (0.5 ml, free of CO2-HCO3-) containing sodium acetate or NH4Cl prolonged perfusion of acid Tyrode's solution (pH 7.20-6.50), and boluses of Tyrode's solution with CO2-HCO3- were used. A decrease of fluorescence indicated pHi turning acid, and an increase of fluorescence indicated a change in alkaline pHi. Chemosensory activity varied inversely with the fluorescence change after application of these agents. Interruption of perfusate flow or application of hypoxic perfusate resulted in large increases in chemosensory discharge without any change in the fluorescence. The results indicated that chemosensory responses to brief ischemia and hypoxia were not mediated by a fall of pHi of CB cells, whereas those to CO2 and extracellular acidity were associated with decreases in pHi.     

Phosphoinositol kinase from germinating mung bean seeds

Phosphoinositol kinase (adenosine triphosphate-inositolmonophosphate phospho—tranferase) has been isolated from cotyledons; about 300-fold purification has been achieved, with a recovery of 11%. The enzyme has a pH optimum at 7·4. It can mediate phosphorylation of lower inositol phosphates to their corresponding higher homologues, ATP being the phosphate donor. ATP can be replaced partially by UTP and PEP. The enzyme requires divalent cations for the reaction. Mn²⁺ has been found to be twice as effective as Mg²⁺, Ca²⁺ being inhibitory. Phosphoinositol kinase has been found to be different from inositol kinase.     

KINETICS OF HAEMOPOIETIC RECOVERY IN ENDOTOXIN-TREATED MICE

Kinetics of mouse spleen colony forming units were studied after intra-peritoneal injection of 1 μ/g body weight bacterial endotoxin S. typhosa. When these mice were used as unirradiated and sublethally irradiated donors, it was possible to study the effect of the endotoxin injection upon the cells. Use of the treated mice as irradiated recipients of normal cells gave information about the host effect. In treated unirradiated mice, the total nucleated cell and the CFU counts were disturbed, and 2 days later a large fraction of the CFU were found in the DNA synthesis (S) phase. This meant that injection of endotoxin generated factors affecting the kinetics of the CFU and triggering the resting CFU into the proliferative cycle. If then the mice were given supralethal irradiation and used as recipients of normal bone marrow cells, more CFU seeded to the spleen as compared to normal recipients; but the dip and the growth rate of the CFU were not changed. Hence the endotoxin-generated factors had been eliminated in 2 days. A total body sublethal irradiation by 400 rad X-ray 2 days after endotoxin injection reduced the post-irradiation dip in the recovery curve of the CFU, indicating that though the factors affecting the cell kinetics had been eliminated, the cycling CFU behaved like a growing population. During the first week, the growth rate of the CFU remained the same as in control irradiated mice. The growth rate of the spleen CFU of the endotoxin-treated mice slowed down during the second week, and their self-replicating ability was low. Fluctuations in the DNA synthesizing fraction of the spleen CFU suggested a variability in the ratio of the length of the S phase and the cell generation time.     

Sudden death during ambulatory monitoring.

Three patients with ischaemic heart disease died suddenly while being monitored with an ambulatory tape recorder. Two had terminal ventricular fibrillation initiated by paired bidirectional ventricular ectopic beats against a background of scattered ectopic activity; both had had ventricular tachycardia during routine treadmill exercise testing in the week before death. The third patient developed bizarre ventricular complexes followed by asystole. Sudden death may be due to ventricular fibrillation initiated by paired ventricular ectopic beats with changing morphology, or asystole following bizarre ventricular complexes. Exercise testing may have an important predictive value.