Admixture Mapping of Obesity‐related Traits in African Americans: The Atherosclerosis Risk in Communities (ARIC) Study

Obesity is an important cause of morbidity and mortality worldwide. In the United States, the prevalence of obesity is higher in African Americans than whites, even after adjustment for socioeconomic status (SES). This leads to the hypothesis that differences in genetic background may contribute to racial/ethnic differences in obesity‐related traits. We tested this hypothesis by conducting a genome‐wide admixture mapping scan using 1,350 ancestry‐informative single‐nucleotide polymorphisms (SNPs) in 3,531 self‐identified blacks from the Atherosclerosis Risk in Communities (ARIC) study. We used these markers to estimate the overall proportions of European ancestry (PEAs) for each individual and then scanned for the association between PEA and obesity‐related traits (both continuous and dichotomous) at each locus. The median (interquartile range) PEA was 0.151 (0.115). PEA was inversely correlated with continuous BMI, weight, and subscapular skinfold thickness, even after adjusting for socioeconomic factors. In contrast, PEA was positively correlated with BMI‐adjusted waist circumference. Using admixture mapping on dichotomized traits, we identified a locus on 2p23.3 to be suggestively associated with BMI (locus‐specific lod = 4.11) and weight (locus‐specific lod = 4.07). After adjusting for global PEA, each additional copy of a European ancestral allele at the 2p23.3 peak was associated with a BMI decrease of ～0.92 kg/m² (P = 2.9 × 10^?5). Further mapping in this region on chromosome 2 may be able to uncover causative variants underlying obesity, which may offer insights into the control of energy homeostasis.     

A survey of keratinophilic fungi as a tool for hen feather utilization

One hundred keratinophilic fungi belonging toAcremonium, Aphanoascus, Amauroascus, Botryotrichum, Chrysosporium, Ctenomyces, Gymnoascus, Malbranchea, Microsporum, Narashimella andVerticillium were tested for their potential to utilize hen feathers as keratinous waste.Acremonium sp. 2 andChrysosporium europae released 494.33 and 457.33 μg/ml protein from feathers respectively.Microsporum gypseum released 698.66 μg/ml protein from feathers. Some of these keratinophilic strains other thanMicrosporum may prove beneficial as tools for rapid utilization of not only feathers but other hard keratinous substrates and their end product may be of industrial importance.     

Extracellular expression and characterization of thermostable lipases, LIP8, LIP14 and LIP18, from Yarrowia lipolytica

Two new lipases, LIP14 and LIP18, along with LIP8 from Yarrowia lipolytica MSR80 were functionally expressed as extracellular proteins with an IgG tag using Escherichia coli HB101 pEZZ18 host vector system. Each enzyme had an optimal activity at pH 7 and 40?°C and was activated by 6?mM Ca(2+) and 90?% (v/v) non-polar solvents but inhibited by 10?mM of each 1,10-phenanthraline, DTNB, PMSF and N-bromosuccinamide. All the enzymes were thermostable with t(1/2) of 52?min, 49?min and 68?min for LIP8, LIP14 and LIP18 at 80?°C, respectively. LIP18 was most thermostable among all with a high arginine: lysine ratio and proline content. All the three lipases showed a preference for oleic acid rich triacylglycerols and oils.     

Keratinophilic fungi in soil of potted plants of indoor environments in Kanpur,India, and their proteolytic ability

One hundred nine isolates of 10 genera representing 20 species of keratinophilic fungi were isolated from soil of planted earthen pots in indoor environments of 15 localities of Kanpur, India, by the hair baiting technique. Microsporum gypseum, Trichophyton vanbreuseghemii, and Botryotrichum piluliferum were found to release 698.66, 512.99, and 519.99 μg/ml net protein, respectively, whereas Arthroderma cuniculi released the minimum, 107.99 μg/ml. All other isolates were keratinolytically active.     

Effect of sesamol on radiation-induced cytotoxicity in Swiss albino mice

The radio-protective ability of sesamol (SM) at various doses viz., 0, 10, 25, 40, 50, 70 and 100mg/kg bw, administered intraperitoneally 30min prior to 9.5Gy whole-body gamma-irradiation was studied in Swiss albino mice. Radiation toxicity and mortality were observed during a period of 30 days and the percentage mortality was calculated. SM pretreatment with 50mg/kg bw was found to be the most effective dose in maintaining body weight and in reducing the percentage mortality, while 100mg/kg bw was found to be more effective in maintaining the spleen index and in stimulation of endogenous spleen colony-forming units. Pretreatment with SM (50mg/kg bw) in mice irradiated with 15Gy significantly reduced dead, inflammatory, mitotic and goblet cells in irradiated jejunum. SM at 50mg/kg bw also increased crypt cells, maintained villus height, and prevented mucosal erosion. Nuclear enlargement in epithelial cells was found less in SM-treated mice compared with the irradiated control. The radiation-induced decrease in endogenous antioxidant enzymes (GSH, GST, catalase) and the increase in lipid peroxidation were also reduced by pretreatment with SM [50 and 100mg/kg bw] at all monitored post-irradiation intervals. There was no protection at a dose less than 25mg/kg bw.     

The NQO1 allelic frequency in hindu population of central India varies from that of other Asian populations

CONTEXT:

The enzymes encoded by the polymorphic genes NAD (P) H: quinone oxidoreductase 1 (NQO1) play an important role in the activation and inactivation of xenobiotics. This enzyme has been associated with xenobiotic related diseases, such as cancer, therapeutic failure and abnormal effects of drugs.

AIM:

The aim of the present study was to determine the allelic and genotypic frequencies of NQO Hinf I polymorphisms in a Hindu population of Central India.

SETTINGS AND DESIGN:

Polymorphisms of NQO1 were determined in 311 unrelated Hindu individuals.

MATERIALS AND METHODS:

Polymerase chain reaction- Restriction Fragment Length Polymorphism (PCR-RFLP) analysis in peripheral blood DNA for NQO1 Hinf I polymorphism was used in 311 unrelated Hindu individuals.

STATISTICAL ANALYSIS:

Allele frequencies were calculated by direct counting. Hardy Weinberg Equilibrium was evaluated using a Chi-square goodness of fit test.

RESULTS:

The observed allelic frequency was 81% for C (wild) and 19% for T (mutant) in the total sample.

CONCLUSIONS:

The allelic frequency of “C” was higher than in other Asians (57%), but similar to Caucasians (81%). The genotype distributions for Hinf I polymorphisms were in Hardy-Weinberg equilibrium.     

Association of mitochondrial nitric oxide synthase activity with respiratory chain complex I

The present study shows that rat liver and brain mitochondrial nitric oxide synthase (mtNOS) are functionally associated with mitochondrial respiratory chain complex I. When complex I is activated, mtNOS exerts high activity and generates nitric oxide, whereas inactivation of complex I leads mtNOS to abandon its NOS activity. Functional association of mtNOS with complex I is potentially important in regulating mtNOS activity and mitochondrial functions.     

Amplification of rat microsatellite loci in Mastomys coucha Smith, 1836

The multimammate rat M. coucha is the most widespread strain to be introduced in biomedical research and various stocks of this strain are maintained in laboratories across the globe. It is an ideal carrier of normally non-human disease to the domestic environment. In order to analyze genetic purity, strains of M. coucha were subjected to PCR-based DNA fingerprinting using sequence tagged microsatellite markers to evolve molecular signature to them. For this, 10 rats sequenced tagged microsatellite markers were used to investigate for their applicability of cross-species amplification in the genome of M. coucha. Out of 10 microsatellite primers tested, four (40%) microsatellite primer pairs [Carboxypeptidase B (CBP), Calmodulin (CALM3), Cell surface protein (CSPMO2) and Insulin like growth factor-I (IGF-1)] could be amplified successfully with exact with product size of 159, 145, 186 and 203 bps respectively in rat. The results suggest that since the above mentioned microsatellite primers get amplified successfully in M. coucha, they may be useful for genetic characterization, evaluation, strain improvement and biomedical research.