Cyclophilin-A: a potential screening marker for vascular disease in type-2 diabetes

The pathophysiology of vascular disease in diabetes involves abnormalities in endothelial cells, vascular smooth muscle cells, and monocytes. The metabolic abnormalities that characterize diabetes, such as hyperglycemia, increased free fatty acids, and insulin resistance, each provoke molecular mechanisms that contribute to vascular dysfunction. Several molecules have been identified as risk markers, and have been studied to prevent progression of disease and long-term complications. Markers such as C-reactive protein and monocyte chemoattractant protein-1 are used to assess risk for adverse cardiac events, but elevated levels are possible due to the presence of other risk factors as part of the natural physiological defense mechanism. In this review we discuss potential of cyclophilin-A, a secreted oxidative-stress-induced immunophilin with diverse functions. We present evidence for a significant role of cyclophilin-A in the pathogenesis of atherosclerosis in diabetes, and its potential as a marker for vascular disease in type-2 diabetes.     

Molecular design of aminopolynitroazole-based high-energy materials

The density functional theory (DFT) was employed to calculate the energetic properties of several aminopolynitroazoles. The calculations were performed to study the effect of amino and nitro substituents on the heats of formation, densities, detonation performances, thermal stabilities, and sensitivity characteristics of azoles. DFT-B3LYP, DFT-B3PW91, and MP2 methods utilizing the basis sets 6-31 G* and 6-311 G (2df, 3p) were adopted to predict HOFs via designed isodesmic reactions. All of the designed aminopolynitroazoles had heats of formation of >220 kJ mol(-1). The crystal densities of the aminopolynitroazoles were predicted with the cvff force field. All of the energetic azoles had densities of >1.83 g/cm(3). The detonation velocities and pressures were evaluated using the Kamlet-Jacobs equations, utilizing the predicted densities and heats of formation. It was found that aminopolynitroazoles have a detonation velocity of about 9.1 km/s and detonation pressure of 36 GPa. The bond dissociation energies for the C-NO(2) and N-NO(2) bonds were analyzed to investigate the stabilities of the designed molecules. The charge on the nitro group was used to assess impact sensitivity in the present study. The results obtained imply that the designed molecules are stable and are expected to be candidates for high-energy materials (HEMs).     

Theoretical study of AlH(2+)n (n=1-7) dications

The structures and stability of 1–7 dications were calculated at the ab initio MP2/aug-cc-pVTZ level of theory. The dications AlH²⁺ 1 and 2 were characterized to be unstable thermodynamically. However, these and the stable dications, 3–7 have considerable kinetic barriers for deprotonation. Each of the structures 3–7 contains one or more two-electron three-center (2e–3c) bonds. Aluminum atoms of these dications carry most of the positive charges, as indicated by NBO charge calculations.Dedicated to Professor Dr. Paul von Ragué Schleyer on the occasion of his 75th birthday     

Development of a novel dual CCR5-dependent and CXCR4-dependent cell-cell fusion assay system with inducible gp160 expression

In the current study, a novel coreceptor-specific cell-cell fusion (CCF) assay system is reported. The system possesses the following features: dual CCR5-dependent and CXCR4-dependent CCF assays, all stable cell lines, inducible expression of gp160 to minimize cytotoxicity, robust luciferase reporter, and 384-well format. These assays have been validated using various known HIV entry inhibitors targeting various stages of the HIV entry/fusion process, including fusion inhibitors, gp120 inhibitors, CCR5 antagonists, CCR5 antibodies, and CXCR4 antagonists. IC50 data generated from this assay system were well correlated to that from the antiviral assays. The effects of DMSO on this assay system were assessed, and a 2- to 3-fold increase in luciferase activity was observed in the presence of 0.05% to 2% DMSO. Although cell-cell fusion efficiency was enhanced, no changes in drug response kinetics for entry inhibitors were found in the presence of 0.1% or 0.5% DMSO. This assay system has been successfully used for the identification and characterization of thousands of CCR5 inhibitors.     

Micropropagation of Searsia dentata

A method for in vitro regeneration of Searsia dentata from nodal and shoot tip explants derived from mature trees is outlined. Nodal explants produced multiple shoots from the axis when cultured on Murashige and Skoog (MS) medium containing 3% sucrose supplemented with 0, 5, 7.5, 10, or 12.5 μM N ⁶-benzyladenine (BA). An average of 5.3 shoots was obtained from nodal explants on 10 μM BA. For shoot tip explants, however, supplementation of α-naphthaleneacetic acid (NAA) with BA favored a caulogenic response. A maximum of 6.1 shoots were produced per shoot tip explant on MS containing 7.5 μM BA plus 5.0 μM NAA. The in vitro-regenerated shoots produced roots when transferred to full-strength MS medium containing 3% sucrose and 10 μM indole-3-butyric acid (IBA). The developed plantlets were transferred initially to a mist house. After an initial acclimatization period of 3–4 mo, plantlets were shifted to the greenhouse where they thrived for 9 mo. The standardized protocol for mass propagation of S. dentata should eliminate the dependence on natural stands of plants for traditional medicinal purposes, and will also serve as a means of conservation as the species is heavily overexploited.     

Occurrence and distribution of multiple antibiotic-resistant <Emphasis Type="Italic">Enterococcus</Emphasis> and <Emphasis Type="Italic">Lactobacillus</Emphasis> spp. from Indian poultry: in vivo transferability of their erythromycin,tetracycline and vancomycin resistance

The objective of this study was to determine the occurrence and distribution of antibiotic resistant (AR) lactic acid bacteria (LAB) in Indian poultry. LAB from poultry farm feces (n = 21) and samples from slaughter houses comprising chicken intestine (n = 46), raw meat (n = 23), and sanitary water (n = 4) were evaluated and compared with those from organic chicken (OC) collected from nearby villages. Screening studies showed 5–7 log units higher erythromycin (ER), tetracycline (TC) and vancomycin (VAN) resistant LAB from conventional poultry chicken (CC) compared to OC. Molecular characterization of isolated cultures (n = 32) with repetitive-PCR profiling and 16S rRNA gene sequencing revealed their taxonomical status as Enterococcus faecium (n = 16), Enterococcus durans (n = 2), Lactobacillus plantarum (n = 10), Lactobacillus pentosus (n = 1) and Lactobacillus salivarius (n = 3). The isolates were found to harbor erm(B), msr(C), msr(A/B), tet(M), tet(L) and tet(K) genes associated with Tn916 and Tn917 family transposons. Expression studies through real-time PCR revealed antibiotic-induced expression of the identified AR genes. In vitro and in vivo conjugational studies revealed transfer of ER and TC resistant (ER^R and TC^R) genes with transfer frequencies of 10^?7 and 10^?4 transconjugants recipient^?1, respectively. Although no known VAN resistance (VAN^R) genes were detected, high phenotypic resistance was observed and was transferable to the recipient. From a public health point of view, this study reports Indian poultry as a major source of high levels of AR bacteria contaminating the food chain and the environment. Thus, urgent and determined strategies are needed to control the spread of multiple AR bacteria.     

Influence of some adjuvants on <Emphasis Type="Italic">in vitro</Emphasis> clonal propagation of male and female jojoba plants

Summary The influence of different adjuvants, activated charcoal (AC), casein hydrolyzate (CH), coconut water (CW), polyvinylpyrrolidone (PVP), and triiodobenzoic acid (TIBA), has been assessed on the shoot production potential of the nodal explants derived from in vitro-raised male and female jojoba (Simmondsia chinensis) shoots. Nodal explants of each sex were cultured separately on Murashige and Skoog medium supplemented with different levels of AC, CW, CH, PVP, and TIBA either alone or along with optimum levels of N ⁶-benzyladenine (BA; 10 μM for male, 20 μM for female). Some differences in response of the explants of both the sexes have been observed in terms of (1) percentage of explants developing shoots, (2) average shoot number, and (3) average shoot length. AC alone proved beneficial for elevating morphogenic response in male as well as female explants in comparison to basal medium or media containing AC and the optimum level of BA. When used alone, CH proved inhibitory for shoot differentiation in both sexes, especially in male explants. Addition of PVP to MS enhanced shoot proliferation in female explants only, but along with BA it increased the response of male explants. BA in combination with different levels of TIBA promoted shoot multiplication in female explants. Thus, explants of both male and female shoots exhibited differential morphogenic behavior under the influence of various adjuvants. However, BA alone proved to be the best for differentiation of shoots in both male (10 μM) as well as female (20 μM) explants.     

Use of a monoclonal antibody to distinguish between precursor and mature forms of human lysosomal alpha-glucosidase

The levels of functional mRNA encoding glucose-6-phosphate dehydrogenase (G6PDH; EC 1.1.1.49) were examined in hepatocytes from fasted and fasted/carbohydrate-refed rats and in hepatocytes inoculated into primary culture. Functional G6PDH mRNA was assessed in a cell-free protein synthesis system in vitro. We observed that hepatocytes from fasted/carbohydrate-refed rats had a 12-fold higher level of mRNA than did hepatocytes from fasted rats. The possibility that the adrenal glucocorticoids and insulin were responsible for the increase in G6PDH mRNA in refed rats was examined by studying the effect of insulin and the synthetic glucocorticoid, dexamethasone, on the level of functional G6PDH mRNA in primary cultures of rat hepatocytes maintained in a chemically defined medium. Hepatocytes from fasted rats were inoculated into primary culture and maintained for 48 h either in the absence of hormones or in the presence of insulin alone, dexamethasone alone or both hormones together. We observed that dexamethasone alone caused a fourfold increase in G6PDH mRNA while insulin caused about a twofold increase. Both hormones together elicited an increase that was additive. A comparison of functional G6PDH mRNA levels with the effect of the hormones on G6PDH activity and relative rate of enzyme synthesis suggests that the glucocorticoid elevates the level of G6PDH mRNA within the cell without causing a concommitant increase in the rate of synthesis of the enzyme or the level of G6PDH activity. The results obtained with the primary cultures of hepatocytes indicate that insulin and the glucocorticoids are probably involved with the regulation of hepatic G6PDH mRNA. However, involvement of other hormones, such as thyroid hormone, seems likely since the induced levels of G6PDH mRNA in hepatocytes in culture was one-third of that observed in refed rats.     

Fasting Activates Fatty Acid Oxidation to Enhance Intestinal Stem Cell Function during Homeostasis and Aging

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