A potential gene delivery strategy using BK virus

Recombinant BK virus (rBKV) is able to express polypeptides under control of its native BKV late promoter. This ability helps to use this construct as a good reporter since it can infect human cells. In this study, we generate a BKV construct containing Renilla luciferase (Rluc) sequences under control of the BKV late promoter. The activity of Rluc was strongly detected in Vero-76 and Cos-1 cells transfected with rBKV-Rluc-myc-2A-VP2 construct, indicating the production of a functional enzyme driven by the native late promoter. Furthermore, a construct made of rBKV-IL2SP-Rluc-myc-2A-VP2 by introducing human IL2 secretion peptide (IL2 SP) caused secretion of IL2SP-Rluc-myc into the culture medium. As a concluding remark, a potential infectious rBKV that can express foreign antigens such as Rluc was generated successfully. The proposed strategy would be useful to engineer recombinant forms of rBKV with many potential applications including development of antiviral assay for new drugs, human vaccines and gene delivery systems for immunotherapeutic or cell transduction.     

Characterization of human serum albumin's interactions with safranal and crocin using multi-spectroscopic and molecular docking techniques

Interaction mechanisms of human serum albumin (HSA) with safranal and crocin were studied using UV–Vis absorption, fluorescence quenching and circular dichroism (CD) spectroscopies as well as molecular docking techniques. Changes in absorbance and fluorescence of HSA upon interactions with both compounds were attributed to their binding to amino acid chromophores located in subdomains IIA and IIIA. Fluorescence secondary inner filter effect was excluded using 278 nm and 340 nm as the wavelengths of HSA's excitation and fluorescence while safranal and crocin absorbed at 320 nm and 445 nm, respectively. Stern-Volmer model revealed a static quenching mechanism involve the formation of non-fluorescent ground state complexes. Stern-Volmer, Hill, Benesi-Hilbrand and Scatchard models gave apparent binding constants ranged in 4.25 × 10³ - 2.15 × 10⁵ for safranal and 7.67 × 10³ - 4.23 × 10⁵ L mol^?1 for crocin. CD measurements indicated that 13 folds of safranal and crocin unfolded the α-helix structure of HSA by 7.47–21.20%. In-silico molecular docking revealed selective exothermic binding of safranal on eight binding sites with binding energies ranged in ?3.969 to ?6.6.913 kcal/mol. Crocin exothermally bound to a new large pocket located on subdomain IIA (sudlow 1) with binding energy of ?12.922 kcal/mol.These results confirmed the formation of HSA stable complexes with safranal and crocin and contributed to our understanding for their binding characteristics (affinities, sites, modes, forces … etc.) and structural changes upon interactions. They also proved that HSA can solubilize and transport both compounds in blood to target tissues. The results are of high importance in determining the pharmacological properties of the two phytochemical compounds and for their future developments as anticancer, antispasmodic, antidepressant or aphrodisiac therapeutic agents.     

The association of cerebrospinal fluid pressure with optic nerve head and macular vessel density

Science China Life Sciences - The present study aims to investigate the effect of temporary cerebrospinal fluid pressure (CSFP) reduction on optic nerve head (ONH) and macular vessel density (VD)...     

The genetics of hybrid male sterility between the allopatric species pair Drosophila persimilis and D. pseudoobscura bogotana: dominant sterility alleles in collinear autosomal regions

F(1) hybrid male sterility is thought to result from interactions between loci on the X chromosome and dominant-acting loci on the autosomes. While X-linked loci that contribute to hybrid male sterility have been precisely localized in many animal taxa, their dominant autosomal interactors have been more difficult to localize precisely and/or have been shown to be of relatively smaller effect. Here, we identified and mapped at least four dominant autosomal factors contributing to hybrid male sterility in the allopatric species pair Drosophila persimilis and D. pseudoobscura bogotana. Using these results, we tested predictions of reduced recombination models of speciation. Consistent with these models, three of the four QTL associated with hybrid male sterility occur in collinear (uninverted) regions of these genomes. Furthermore, these QTL do not contribute significantly to hybrid male sterility in crosses between the sympatric species D. persimilis and D. pseudoobscura pseudoobscura. The autosomal loci identified in this study provide the basis for introgression mapping and, ultimately, for molecular cloning of interacting genes that contribute to F(1) hybrid sterility.     

HPLC separation technique for analysis of bufuralol enantiomers in plasma and pharmaceutical formulations using a vancomycin chiral stationary phase and UV detection

A sensitive and selective high-performance liquid chromatographic (HPLC) method has been developed for the simultaneous determination of bufuralol enantiomers in plasma and pharmaceutical formulations. Enantiomeric resolution was achieved on a vancomycin macrocyclic antibiotic chiral stationary phase (CSP) known as Chirobiotic V with UV detection set at 254 nm. The polar ionic mobile phase (PIM) consisting of methanol-glacial acetic acid-triethylamine (100:0.015:0.010, v/v/v) has been used at a flow rate of 0.5 ml/min. The method is highly specific where other coformulated compounds did not interfere. The stability of bufuralol enantiomers under different degrees of temperature was also studied. The results showed that the drug is stable for at least 7 days at 70 degrees C. The method was validated for its linearity, accuracy, precision and robustness. An experimental design was used during validation to evaluate method robustness. The calibration curves in plasma were linear over the range of 5-500 ng/ml for each enantiomer with detection limit of 2 ng/ml. The mean relative standard deviation (RSD) of the results of within-day precision and accuracy of the drug were 0.05) between inter- and intra-day studies for each enantiomer which confirmed the reproducibility of the assay method. The mean extraction efficiency for S-(-)- and R-(+)-bufuralol from plasma was in the range 97-102% at 15-400 ng/ml level for each enantiomer. The overall recoveries of bufuralol enantiomers from pharmaceutical formulations was in the range 99.6-102.2% with %RSD ranging from 1.06 to 1.16%. The assay method proved to be suitable as chiral quality control for bufuralol formulations by HPLC and for therapeutic drug monitoring.     

Chemical composition and antimicrobial activity of the essential oil of Teucrium ramosissimum (Lamiaceae)

The phytochemical composition of the essential oil of Teucrium ramosissimum (aerial parts), harvested in a mountainous region of Tunisia, was analyzed. A total of 68 compounds, accounting for 99.44% of the essential oil, were identified by GC and GC/MS. The major compounds were beta-eudesmol (61; 44.52%), caryophyllene oxide (56; 9.35%), alpha-thujene (1; 5.51%), sabinene (4; 4.71%), and T-cadinol (59; 3.9%). The essential oil, which is being used in Tunisian folk medicine against infectious diseases, was tested for its antimicrobial properties against five different bacteria, and found to have weak to moderate activity, with minimal-inhibitory-concentration (MIC) and minimal-bactericidal-concentration (MBC) values in the range 0.24-0.36 and 1.3-2.9 mg/ml, resp.     

Hormonal status of cortisol and dehydroepiandrosterone sulfate in an elderly Tunisian population

Adrenal function and aging have been the object of intense interest recently, especially as regards dehydroepiandrosterone sulfate (DHEA-S), which is of major importance, since it is distinct from cortisol and aldosterone in declining with age. In a group of healthy old Tunisians, we investigated the association between cortisol and DHEA-S, on the one hand, and age, sex, lifestyle, physical health, including the body mass index (BMI), physical activity, and smoking indicators, on the other hand. We observed that cortisol concentrations did not change with aging, while DHEA-S concentrations decrease with age in both sexes. Cortisol/DHEA-S ratio, however, increases with aging. Our results revealed that DHEA-S levels are affected neither by physical activity nor by weight. It appears also that current smoking could not affect the level of DHEA-S. Relationships were found between DHEA-S concentrations and BMI, then between DHEA-S levels and serum cholesterol, triglycerides and calcium. No modification in the morning serum cortisol was found to be associated with aging. Decrease in DHEA-S levels is, however, clearly associated with this phenomenon. High cortisol/DHEA-S ratio accelerates the occurrence of some adult diseases, such as diabetes mellitus, atherosclerosis, dementia, and osteoporosis. Generally, the adrenal insufficiency marked by a cognitive impairment, immune disorders, sexual dysfunction, and scores for depression and anxiety can be corrected by a replacement of deficient DHEA-S.     

Y chromosome lineage- and village-specific genes on chromosomes 1p22 and 6q27 control visceral leishmaniasis in Sudan

Familial clustering and ethnic differences suggest that visceral leishmaniasis caused by Leishmania donovani is under genetic control. A recent genome scan provided evidence for a major susceptibility gene on Chromosome 22q12 in the Aringa ethnic group in Sudan. We now report a genome-wide scan using 69 families with 173 affected relatives from two villages occupied by the related Masalit ethnic group. A primary ten-centimorgan scan followed by refined mapping provided evidence for major loci at 1p22 (LOD score 5.65; nominal p = 1.72 × 10⁻⁷; empirical p < 1 × 10⁻⁵; λ_S = 5.1) and 6q27 (LOD score 3.74; nominal p = 1.68 × 10⁻⁵; empirical p < 1 × 10⁻⁴; λ_S = 2.3) that were Y chromosome–lineage and village-specific. Neither village supported a visceral leishmaniasis susceptibility gene on 22q12. The results suggest strong lineage-specific genes due to founder effect and consanguinity in these recently immigrant populations. These chance events in ethnically uniform African populations provide a powerful resource in the search for genes and mechanisms that regulate this complex disease.