Effect of ultraviolet B (302 nm) irradiation on viability, metabolic and detoxification functions of goat hepatocytes – in vitro study

The object of the present study was to investigate the effect(s) of UV-B irradiation on the functional integrity, metabolic and detoxifying capacity of the isolated goat hepatocytes. Isolated goat hepatocytes were subjected to UV-B irradiation invitro for 0, 250, 500, 1250, 2500 and 7500 Joules/m² which correspond to the irradiation time of 0, 1, 2, 5, 10 and 30 min. Cells were then analysed for Viability (Trypan blue exclusion test [TBE], 3-[4,5-dimethylthiozol-2yl]-2,5-diphenyltetrazolium bromide [MTT] assay, Membrane integrity (Lactate dehydrogenase [LDH] leakage, Lipid peroxidation) Detoxification (Ureagenesis, Cytochrome P450 activity [CYP450, Diazepam metabolism] and Glutathione-S-Transferase [GST] activity. The results show that there was no difference in functional, metabolic as well as detoxifying parameters of the hepatocytes when irradiated from 0–1250 Joules/m², whereas a significant alteration was appreciable in the parameters such as LDH leakage, lipid peroxidation, and CYP450 activity when irradiated beyond 1250 Joules/m². Our present findings suggest that the biologically compatible and feasible dose of UV-B irradiation for xenotransplantation appears to be 1250 Joules/m².     

Different population histories of the Mundari- and Mon-Khmer-speaking Austro-Asiatic tribes inferred from the mtDNA 9-bp deletion/insertion polymorphism in Indian populations

Length variation in the human mtDNA intergenic region between the cytochrome oxidase II (COII) and tRNA lysine (tRNA^lys) genes has been widely studied in world populations. Specifically, Austronesian populations of the Pacific and Austro-Asiatic populations of southeast Asia most frequently carry the 9-bp deletion in that region implying their shared common ancestry in haplogroup B. Furthermore, multiple independent origins of the 9-bp deletion at the background of other mtDNA haplogroups has been shown in populations of Africa, Europe, Australia, and India. We have analyzed 3293 Indian individuals belonging to 58 populations, representing different caste, tribal, and religious groups, for the length variation in the 9-bp motif. The 9-bp deletion (one copy) and insertion (three copies) alleles were observed in 2.51% (2.15% deletion and 0.36% insertion) of the individuals. The maximum frequency of the deletion (45.8%) was observed in the Nicobarese in association with the haplogroup B5a D-loop motif that is common throughout southeast Asia. The low polymorphism in the D-loop sequence of the Nicobarese B5a samples suggests their recent origin and a founder effect, probably involving migration from southeast Asia. Interestingly, none of the 302 (except one Munda sample, which has 9-bp insertion) from Mundari-speaking Austro-Asiatic populations from the Indian mainland showed the length polymorphism of the 9-bp motif, pointing either to their independent origin from the Mon-Khmeric-speaking Nicobarese or to an extensive admixture with neighboring Indo-European-speaking populations. Consistent with previous reports, the Indo-European and Dravidic populations of India showed low frequency of the 9-bp deletion/insertion. More than 18 independent origins of the deletion or insertion mutation could be inferred in the phylogenetic analysis of the D-loop sequences.     

Hemolysis of Human Red Blood Cells by Riboflavin-Cu(II) System: Enhancement by Azide

Photoactivated riboflavin in the presence of Cu(II) generates reactive oxygen species (ROS) which can hemolyze human red blood cells (RBC). In the present work we examined the effect of sodium azide (NaN3) on RBC in the presence of riboflavin and Cu(II). The addition of NaN3 to the riboflavin-Cu(II) system enhanced K+ loss and hemolysis. The extent of K+ loss and hemolysis were time and concentration dependent. Bathocuproine, a Cu(I)-sequestering agent, inhibited the hemolysis completely. Among various free radical scavengers used to identify the major ROS involved in the reaction, thiourea was found to be the most effective scavenger. Thiourea caused almost 85% inhibition of hemolysis suggesting that *OH is the major ROS involved in the reaction. Using spectral studies and other observations, we propose that when NaN3 is added to the riboflavin-Cu(II) system, it inhibits the photodegradation of riboflavin resulting in increased *OH generation. Also, the possibility of azide radical formation and its involvement in the reaction could not be ruled out.     

Chronic orchidectomy does not influence the sensitivity of the pituitary somatotropes to varying doses of GHRH administered intravenously to the adult male rhesus monkey

In the present study, the pituitary growth hormone (GH) response to graded doses of GH-releasing hormone (GHRH) was determined in intact (n = 3) and chronically orchidectomized (n = 3) adult rhesus monkeys (Mucaca mulatta). GHRH in doses of 0, 6.25, 12.5 and 25 microg/kg BW was infused through a teflon cannula implanted in the saphenous vein. Blood samples were collected 60 min before and 90 min after the injection of the neurohormone at 15 min intervals. All bleedings were carried out under ketamine hydrochloride anesthesia. The plasma levels of GH were determined by using AutoDELFIA time-resolved flouroimmunoassay, whereas plasma levels of testosterone and estradiol were determined using specific radioimmunoassay systems. The GH responses to GHRH were not significantly different between intact and chronically orchidectomized monkeys at any of the dose levels tested (p > 0.05). The administration of GHRH resulted in a significant (p < 0.05) stimulation of GH secretion at all the doses tested and in both the groups studied. In both intact and orchidectomized animals, the greatest response was observed at 6.25 microg/kg and no further increase was noted with the higher doses of GHRH. In conclusion, the present study suggests that chronic orchidectomy does not influence the sensitivity of the pituitary somatotropes to GHRH stimulation implying that the responsiveness of the pituitary somatotropes to GHRH is independent of testicular steroid modulation.     

Global patterns in human mitochondrial DNA and Y-chromosome variation caused by spatial instability of the local cultural processes

Because of the widespread phenomenon of patrilocality, it is hypothesized that Y-chromosome variants tend to be more localized geographically than those of mitochondrial DNA (mtDNA). Empirical evidence confirmatory to this hypothesis was subsequently provided among certain patrilocal and matrilocal groups of Thailand, which conforms to the isolation by distance mode of gene diffusion. However, we expect intuitively that the patterns of genetic variability may not be consistent with the above hypothesis among populations with different social norms governing the institution of marriage, particularly among those that adhere to strict endogamy rules. We test the universality of this hypothesis by analyzing Y-chromosome and mtDNA data in three different sets of Indian populations that follow endogamy rules to varying degrees. Our analysis of the Indian patrilocal and the matrilocal groups is not confirmatory to the sex-specific variation observed among the tribes of Thailand. Our results indicate spatial instability of the impact of different cultural processes on the genetic variability, resulting in the lack of universality of the hypothesized pattern of greater Y-chromosome variation when compared to that of mtDNA among the patrilocal populations.     

A shared Y-chromosomal heritage between Muslims and Hindus in India

Arab forces conquered the Indus Delta region in 711 AD and, although a Muslim state was established there, their influence was barely felt in the rest of South Asia at that time. By the end of the tenth century, Central Asian Muslims moved into India from the northwest and expanded throughout the subcontinent. Muslim communities are now the largest minority religion in India, comprising more than 138 million people in a predominantly Hindu population of over one billion. It is unclear whether the Muslim expansion in India was a purely cultural phenomenon or had a genetic impact on the local population. To address this question from a male perspective, we typed eight microsatellite loci and 16 binary markers from the Y chromosome in 246 Muslims from Andhra Pradesh, and compared them to published data on 4,204 males from East Asia, Central Asia, other parts of India, Sri Lanka, Pakistan, Iran, the Middle East, Turkey, Egypt and Morocco. We find that the Muslim populations in general are genetically closer to their non-Muslim geographical neighbors than to other Muslims in India, and that there is a highly significant correlation between genetics and geography (but not religion). Our findings indicate that, despite the documented practice of marriage between Muslim men and Hindu women, Islamization in India did not involve large-scale replacement of Hindu Y chromosomes. The Muslim expansion in India was predominantly a cultural change and was not accompanied by significant gene flow, as seen in other places, such as China and Central Asia.Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.Ramana Gutala and Denise R. Carvalho-Silva contributed equally to the article.     

Genetic affinities among the lower castes and tribal groups of India: inference from Y chromosome and mitochondrial DNA

Background

Past work on asthmatic African American families revealed a strong linkage peak with modest evidence of association on chromosome 11q. Here, we perform tests of association for asthma and a panel of 609 SNPs in African American subjects using a sliding window approach. While efficient in screening a region of dense genotyping, this approach does create some problems: high numbers of tests, assimilating thousands of results, and questions about setting priorities on regions with association signals.

Results

We present a newly developed tool, Graphical Assessment of Sliding P-values or GrASP, which uses color display to indicate the width of the sliding windows, significance of individual tests, density of SNP coverage and location of known genes that simplifies some of these issues, and use it to identify regions of interest in these data.

Conclusion

We demonstrate that GrASP makes it easier to visualize, summarize and prioritize regions of interest from sliding window haplotype analysis, based jointly on the p-value from all the tests from these windows and the building of haplotypes of significance in the region. Using this approach, five regions yielded strong evidence for linkage and association with asthma, including the prior peak linkage region.     

Sex chromosome associated satellite DNA: Evolution and conservation

Satellites visible in female but not in male DNA were isolated from the snakesElaphe radiata (satellite IV, p = 1.708 g · cm^–3) andBungarus fasciatus (BK¹ minor, p=1.709 g · cm^–3). The satellites cross hybridize. Hybridization of³H labelled nick translated BK minor satellite DNA with the total male and female DNA and/or chromosomes in situ of different species of snakes revealed that its sequences are conserved throughout the snake group and are mainly concentrated on the W chromosome. Snakes lacking sex chromosomes do possess related sequences but there is no sex difference and visible related satellites are absent. The following conclusions have been reached on the basis of these results. 1. The W chromosome associated satellite DNA is related to similar sequences scattered in the genome. 2. The origin and increment in the number of the W satellite DNA sequence on the W chromosome is associated with the heterochromatinization of the W. 3. Satellite sequences have become distributed along the length of the W and resulted in morphological differentiation of sex chromosomes. 4. Evolutionary conservation of W satellite DNA strongly suggests that functional constraints may have limited sequence divergence.     

Herders of Indian and European cattle share their predominant allele for lactase persistence

Milk consumption and lactose digestion after weaning are exclusively human traits made possible by the continued production of the enzyme lactase in adulthood. Multiple independent mutations in a 100-bp region--part of an enhancer--approximately 14-kb upstream of the LCT gene are associated with this trait in Europeans and pastoralists from Saudi Arabia and Africa. However, a single mutation of purported western Eurasian origin accounts for much of observed lactase persistence outside Africa. Given the high levels of present-day milk consumption in India, together with archaeological and genetic evidence for the independent domestication of cattle in the Indus valley roughly 7,000 years ago, we sought to determine whether lactase persistence has evolved independently in the subcontinent. Here, we present the results of the first comprehensive survey of the LCT enhancer region in south Asia. Having genotyped 2,284 DNA samples from across the Indian subcontinent, we find that the previously described west Eurasian -13910 C>T mutation accounts for nearly all the genetic variation we observed in the 400- to 700-bp LCT regulatory region that we sequenced. Geography is a significant predictor of -13910*T allele frequency, and consistent with other genomic loci, its distribution in India follows a general northwest to southeast declining pattern, although frequencies among certain neighboring populations vary substantially. We confirm that the mutation is identical by descent to the European allele and is associated with the same>1 Mb extended haplotype in both populations.     

Alternaria induces STAT6-dependent acute airway eosinophilia and epithelial FIZZ1 expression that promotes airway fibrosis and epithelial thickness

The fungal allergen, Alternaria, is specifically associated with severe asthma, including life-threatening exacerbations. To better understand the acute innate airway response to Alternaria, naive wild-type (WT) mice were challenged once intranasally with Alternaria. Naive WT mice developed significant bronchoalveolar lavage eosinophilia following Alternaria challenge when analyzed 24 h later. In contrast to Alternaria, neither Aspergillus nor Candida induced bronchoalveolar lavage eosinophilia. Gene microarray analysis of airway epithelial cell brushings demonstrated that Alternaria-challenged naive WT mice had a >20-fold increase in the level of expression of found in inflammatory zone 1 (FIZZ1/Retnla), a resistin-like molecule. Lung immunostaining confirmed strong airway epithelial FIZZ1 expression as early as 3 h after a single Alternaria challenge that persisted for ≥5 d and was significantly reduced in STAT6-deficient, but not protease-activated receptor 2-deficient mice. Bone marrow chimera studies revealed that STAT6 expressed in lung cells was required for epithelial FIZZ1 expression, whereas STAT6 present in bone marrow-derived cells contributed to airway eosinophilia. Studies investigating which cells in the nonchallenged lung bind FIZZ1 demonstrated that CD45(+)CD11c(+) cells (macrophages and dendritic cells), as well as collagen-1-producing CD45(-) cells (fibroblasts), can bind to FIZZ1. Importantly, direct administration of recombinant FIZZ1 to naive WT mice led to airway eosinophilia, peribronchial fibrosis, and increased thickness of the airway epithelium. Thus, Alternaria induces STAT6-dependent acute airway eosinophilia and epithelial FIZZ1 expression that promotes airway fibrosis and epithelial thickness. This may provide some insight into the uniquely pathogenic aspects of Alternaria-associated asthma.