Expression levels of genes for ATP-binding cassette transporters and sterol 27-hydroxylase in liver and intestine of baboons with high and low cholesterolemic responses to dietary lipids

Baboons with high and low lipemic responses to dietary lipids differ in intestinal cholesterol absorption and hepatic cholesterol metabolism. ATP-binding cassette (ABC) transporters play an important role in cholesterol absorption and hepatic cholesterol metabolism. Using frozen tissues from high- and low-responding baboons maintained on the cholesterol and fat-enriched diet, we determined the relative expression of ABCA1, ABCG5, ABCG8, and 27-hydroxylase genes in the liver and intestine using TaqMan real-time polymerase chain reaction. There was no consistent difference in the expression of ABC-transporters and 27-hydroxylase in the intestine between high- and low-responding baboons. However, hepatic expression of sterol 27-hydroxylase, ABCG5, and ABCG8 was higher in low-responding baboons than in high-responding baboons. There was also a significant correlation between the expression of sterol 27-hydroxylase and ABCG5, and ABCG8 in both the liver and the intestine. These results suggest that differences in hepatic lipid metabolism but not in cholesterol absorption between high- and low-responding baboons observed previously may be mediated by the differences in the expression levels of 27-hydroxylase, ABCG5, and ABCG8.     

A simple structured mathematical model for biopolymer (PHB) production

Economic production technology for a biodegradable polymer (poly-beta-hydroxybutyrate, PHB) is urgently required to replace conventional polymers, which have an inherent disadvantage of staying in the environment forever. Various approaches have been applied for improving the productivity and reducing the production cost, which are considered to be the two major problems associated with industrial production of PHB. One of the engineering approaches to improve PHB productivity could be to design and implement model-based fed-batch cultivations to provide desirable nutrient availability. In the present study, growth and intracellular biopolymer storage kinetics of Ralstonia eutropha was studied in a batch cultivation process. It featured 19.7 g/L biomass and 10.89 g/L PHB with a productivity of 0.18 g/L.h. The effect of carbon, nitrogen, and phosphate limitations and inhibitions on growth was studied in detail. A structured model featuring typical growth limitations and/or possible inhibitions was then proposed. The value of the model parameters was found by minimizing the difference between experimental value and model simulation at all data points and for all process variables. The optimal batch model parameter values obtained above were used to solve the differential equations numerically. The simulated data obtained in this way was then compared with the experimental data to establish the validity of the batch model. The proposed model was then compared with literature reported mathematical models to reconfirm its accuracy. Statistical validity of the developed model and historical models to describe the observed experimental kinetics was then investigated to reinforce the accuracy of the developed simple model.     

Synthesis and evaluation of S-4-(3-thienyl)phenyl-alpha-methylacetic acid

Herein we report an efficient procedure to synthesize S-4-(3-thienyl)phenyl-alpha-methylacetic acid, an enantiomerically pure intermediate of a recently approved nonsteroidal antiinflammatory cyclooxygenase inhibitor, atliprofen [methyl RS-4-(3-thienyl)phenyl-alpha-methylacetate]. The interactions of the active S-isomer of the acid were theoretically compared with those of S-ibuprofen through molecular docking studies using COX-1 and COX-2 protein structures. The results were corroborated by in vitro and in vivo studies.     

Genotoxic and Mutagenic Assessment of Hexavalent Chromium in Fish Following In Vivo Chronic Exposure

Chromium is a well-documented carcinogen. To evaluate the genotoxic potential of hexavalent chromium on an aquatic bio-system, freshwater murrel fish (Channa punctatus) were exposed to potassium dichromate. The 96-h LC₅₀ for potassium dichromate was 61.80 mg/L for the test fish in a static system. On the basis of the 96-h LC₅₀, fish were exposed to sublethal concentrations of the test chemical. Fish exposed to the test chemical were sampled on days 1, 7, 14, 21, and 28 post-exposure and blood and gill cells were collected. Significantly (p < .05) higher DNA damage in both lymphocyte and gillcells and micronuclei formation in whole blood was observed at different test concentrations and sampling times of the test chemical as compared to control fish. The mean% tail DNA in the comet tail assay showed a concentration-dependent increase and the maximum% tail DNA was observed on day 7 of exposure in both cells. A similar trend was also observed in micronuclei induction in blood with maximum induction on day 21. Hexavalent chromium showed genotoxic potential in chronic exposure of C. punctatus, and the micronucleus test and the comet assay are the methods for sensitive and rapid detection of the genetic effects.     

Genome editing with CompoZr custom zinc finger nucleases (ZFNs)

Genome editing is a powerful technique that can be used to elucidate gene function and the genetic basis of disease. Traditional gene editing methods such as chemical-based mutagenesis or random integration of DNA sequences confer indiscriminate genetic changes in an overall inefficient manner and require incorporation of undesirable synthetic sequences or use of aberrant culture conditions, potentially confusing biological study. By contrast, transient ZFN expression in a cell can facilitate precise, heritable gene editing in a highly efficient manner without the need for administration of chemicals or integration of synthetic transgenes. Zinc finger nucleases (ZFNs) are enzymes which bind and cut distinct sequences of double-stranded DNA (dsDNA). A functional CompoZr ZFN unit consists of two individual monomeric proteins that bind a DNA "half-site" of approximately 15-18 nucleotides (see Figure 1). When two ZFN monomers "home" to their adjacent target sites the DNA-cleavage domains dimerize and create a double-strand break (DSB) in the DNA. Introduction of ZFN-mediated DSBs in the genome lays a foundation for highly efficient genome editing. Imperfect repair of DSBs in a cell via the non-homologous end-joining (NHEJ) DNA repair pathway can result in small insertions and deletions (indels). Creation of indels within the gene coding sequence of a cell can result in frameshift and subsequent functional knockout of a gene locus at high efficiency. While this protocol describes the use of ZFNs to create a gene knockout, integration of transgenes may also be conducted via homology-directed repair at the ZFN cut site. The CompoZr Custom ZFN Service represents a systematic, comprehensive, and well-characterized approach to targeted gene editing for the scientific community with ZFN technology. Sigma scientists work closely with investigators to 1) perform due diligence analysis including analysis of relevant gene structure, biology, and model system pursuant to the project goals, 2) apply this knowledge to develop a sound targeting strategy, 3) then design, build, and functionally validate ZFNs for activity in a relevant cell line. The investigator receives positive control genomic DNA and primers, and ready-to-use ZFN reagents supplied in both plasmid DNA and in-vitro transcribed mRNA format. These reagents may then be delivered for transient expression in the investigator's cell line or cell type of choice. Samples are then tested for gene editing at the locus of interest by standard molecular biology techniques including PCR amplification, enzymatic digest, and electrophoresis. After positive signal for gene editing is detected in the initial population, cells are single-cell cloned and genotyped for identification of mutant clones/alleles.     

Plant growth promoting potential of bacteria isolated on N free media from rhizosphere of Cassia occidentalis

Plant growth promoting rhizobacteria (PGPR) are an attractive eco-friendly alternative to chemicals in agriculture. While the rhizospheres of crop plants have been well studied with the objective of screening PGPR, weeds, which play an important role in maintaining ecological balance, have largely been ignored. The rhizosphere of a luxuriantly growing, medicinal weed, Cassia occidentalis was analysed by enumerating PGPR on N free media from the most diverse stage of plant (determined by profiles obtained on denaturing gradient gel electrophoresis). Each isolate was tested for other plant growth promotion assays including production of cellulase, indole acetic acid (IAA), ammonia, HCN, siderophore and chitinase to select for ones possessing multi-trait plant growth promoting (PGP) properties. Selected isolates were used for bacterization of Vigna radiata and Vigna mungo to evaluate their efficacy in promoting plant's growth in seedling germination and axenic pot conditions. Thirty five isolates were analysed further for the array of PGP properties they exhibit. A total of 6 isolates were shortlisted on the basis of maximum traits positive, amount of phosphate solubilized and IAA produced. V. radiata responded well to seed bacterization during seedling germination. A maximum increase of approximately 36 and 60?% was observed for shoot and root length, respectively in V. radiata in axenic pot culture over control plants. Extensive branching of roots was also observed with isolate NL, which produced the maximum amount of IAA. Present study investigated the plant growth promoting isolates obtained on N free media in the rhizosphere of C. occidentalis, which have the potential to be used as inoculants for other crops. This provides a new dimension to the significance of weeds in agricultural ecosystems. The study opens up possibilities for utilization of this property of weeds in plant growth promotion, and subsequent enhancement of yield for agricultural crops.     

Periodontal health status in the elderly with different levels of education: a 5-year follow-up study

doi: 10.1111/j.1741‐2358.2010.00437.x Periodontal health status in the elderly with different levels of education: a 5‐year follow‐up study Objective: To assess the association between the periodontal health status and level of education over a 5‐year period among the elderly aged 75 years and older. Background: Oral health among the higher educated is known to be better than among the less‐well educated. On the other hand, the prevalence and severity of periodontal disease has been found to grow with increasing age. Methods: The participants were derived from a population‐based Helsinki Aging Study, a random sample of 76‐, 81‐ and 86‐year‐old elderly. The 170 dentate elderly who underwent clinical oral examinations at baseline and 71 who participated in the follow‐up were included in this study. The data was collected from intraoral and radiological examinations and from a structured questionnaire. Results: Subjects with a higher level of education had more retained teeth than subjects with a lower level of education. According to CPITN index, better‐educated participants had more healthy sextants, but they also had more sextants with periodontal pockets. Radiographic examination showed similar results. Conclusion: Level of education has a clear effect on the periodontal health status in the elderly. More treatment need seems to polarise into those elderly who are better educated as they retain more teeth into old age.     

In vitro and in vivo antifilarial activity evaluation of 3,6-epoxy [1,5]dioxocines: a new class of antifilarial agents

A series of 3,6-epoxy [1,5]dioxocines were synthesized and evaluated for their antifilarial activity against adult parasites of human lymphatic filarial parasite Brugia malayi (sub-periodic strain) in vitro. Out of these, six compounds (4a-f) possessed improved in vitro anti-filarial activity and examples 4d and 4f were also found to be active in the in vivo experiments. These results demonstrate that 3,6-epoxy [1,5]dioxocines exhibits potent antifilarial activity and might be developed into a new class of antifilarial drug.     

Constituents of Dalbergia sissoo Roxb. leaves with osteogenic activity

One new isoflavone glucoside, caviunin 7-O-[β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside] (10) and a new itaconic derivative, (E)-4-methoxy-2-(3,4-dihydroxybenzylidene)-4-oxobutanoic acid (15) along with series of isoflavones and flavonols with their glucosides (1-9 and 11-14) and a lignan glucoside (16) were isolated from the ethanolic extract of Dalbergia sissoo leaves. The structures of these compounds were established on the basis of IR, UV, (1)H and (13)C NMR, DEPT, COSY, HSQC, HMBC and MS data. All compounds (1-16) were assessed for osteogenic activity in primary calvarial osteoblast cultures. Compounds 1-4 and 10 increased alkaline phosphatase activity and mineralization thus resulting in significant osteogenic activity.     

An analysis of altitudinal behavior of tree species in Subansiri district,Eastern Himalaya

Plant species diversity and endemism demonstrate a definite trend along altitude. We analyzed the (i) pattern of tree diversity and its endemic subset (ii) frequency distribution of altitudinal range and (iii) upper & lower distributional limits of each tree species along altitudinal gradients in eastern Himalaya. The study was conducted in Subansiri district of Arunachal Pradesh. Data on the tree species (cbh ≥ 15 cm) were gathered every 200 m steps between 200 m and 2200 m gradients. Tree diversity demonstrated a greater variation along the gradients. A total of 336 species (of which 26 are endemic) were recorded belonging to 185 genera and 78 families. The alpha diversity demonstrated a decreasing pattern with two maxima (i.e., elevational peaks) along the gradients; one in 601–1000 m and the other in 1601–1800 m, corresponding to transition zones between tropical-subtropical and subtropical-temperate forests. Pattern diversity revealed a narrow range along the gradients. Frequency of altitudinal range was distributed between 1 and 41. Only one species (Altingia excelsa) showed widest amplitude, occurring over the entire range. Highest level of species turnover was found in 400–600 m step at lower elevational limit whereas for upper elevational limit, the highest turn over was recorded between 800 and 1000 m. Tree diversity decreased and its endemic subset increased along the gradients. Two maximas in tree diversity pattern correspond to forest transition zones with subtropical-temperate transition is narrower than tropical-subtropical. The pattern observed here could be attributed to varied microclimates or environmental heterogeneity. If altitudinal amplitude of a species is considered as an aspect of its niche breadth, it is clear from these results that niche breadth in these organisms is in fact independent of the diversity of the assemblage in which they occur. This analysis calls for detailed floristic studies to determine the breadth of changes between adjacent forest types and details of local species richness in high diversity areas.