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31.
Bisphenol A (BPA) is a man-made compound used to make polycarbonate plastics and epoxy resins; public health concerns have been fueled by findings that BPA exposure can reduce sex differences in brain and some behaviors. We asked if a low BPA dose, within the range measured in humans, ingested during pregnancy, would affect social behaviors in prepubertal mice. We noted sex differences in social interactions whereby females spent more time sitting side-by-side, while males engaged in more exploring and sitting alone. In addition BPA increased display of nose-to-nose contacts, play solicitations and approaches in both sexes. Interactions between sex and diet were found for self grooming, social interactions while sitting side-by-side and following the other mouse. In all these cases interactions were produced by differences between control and BPA females. We examined brains from embryos during late gestation to determine if gene expression differences might be correlated with some of the sexually dimorphic or BPA affected behaviors we observed. Because BPA treatments ended at birth we took the brains during embryogenesis to increase the probability of discovering BPA mediated effects. We also selected this embryonic age (E18.5) because it coincides with the onset of sexual differentiation of the brain. Interestingly, mRNA for the glutamate transporter, Slc1a1, was enhanced by exposure to BPA in female brains. Also we noted that BPA changed the expression of two of the three DNA methyltransferase genes, Dnmt1 and Dnmt3a. We propose that BPA affects DNA methylation of Sc1a1 during neural development. Sex differences in juvenile social interactions are affected by BPA and in particular this compound modifies behavior in females. 相似文献
32.
33.
BACKGROUND:
Hemophilia A (HA), being an X-linked recessive disorder, females are rarely affected, although they can be carriers.AIMS:
To study the mutation in F8 gene in an extended family with a homozygous female HA.MATERIALS AND METHODS:
All the seven affected members (six males and one female) were initially screened by Conformation Sensitive Gel Electrophoresis (CSGE) and direct DNA sequencing.RESULTS:
A homozygous missense mutation c.1315G>A (p.Gly420Ser) was identified in exon 9 of F8 gene in homozygous state in the affected female born of 1° consanguinous marriage and in all the affected male members of the family. Her factor VIII levels was found to be 5.5%, vWF:Ag 120%.CONCLUSION:
In India, as consanguineous marriages are very common in certain communities (up to 30%), the likelihood of encountering female hemophilia is higher, although this is the first case of HA out of 1600 hemophilia families registered in our Comprehensive Haemophilia Care Center. Genetic diagnosis in such cases is not necessary as all the male children will be affected and daughters obligatory carriers. 相似文献34.
Ashwin Mohan Supriya Dabir Naresh Kumar Yadav Matthew Kummelil Rajesh S. Kumar Rohit Shetty 《PloS one》2015,10(4)
Objective
To study the oxygen saturation profile in normal Asian Indian eyes.Design
A cross sectional prospective study.Subjects
Ninety eight consecutive patients presenting to our hospital with best corrected distance visual acuity (BCVA) of 20/20 and a normal ophthalmic examination were included in the study. Patients having any ocular or systemic disease were excluded from the study.Materials and Methods
Oximetry was performed on all subjects with the Oxymap T1 retinal oximeter (Oxymap hf, Reykjavik, Iceland).Main Outcome Measures
The images were analysed for oxygen saturation and diameter.Results
The mean age was 33 years (Range: 18-63; SD: 12.4). The average arteriolar saturation was 90.3 ± 6.6% and the venous saturation was 56.9% ± 6.3. The average A-V (arterio-venous) difference was 33.2% ± 5.2. There was an increase in arteriolar (R2 = 0.264; p=0.001) and venous saturation (R2 = 0.151; p=0.001) with age. There was no significant change in the arterio-venous saturation difference (AVSD). The inferotemporal quadrant had the lowest saturations. Age correlated positively with ocular perfusion pressure (OPP)(R2 = 0.07; p=0.007). OPP correlated positively with global arteriolar saturation (R2=0.057, p=0.018).Conclusion
This study provides the normative database for an Indian population and is comparable to previous studies. Age, vessel diameter and OPP were the significant factors that influenced the saturation. Arteriolar and venous saturations increased with age while the AVSD did not change significantly. 相似文献35.
36.
Urokinase plasminogen activator (uPA) is a serine protease that catalyzes the conversion of plasminogen to plasmin. The plasminogen/plasmin system includes the uPA, its receptor, and its inhibitor (plasminogen activator inhibitor-1). Interactions between these molecules regulate cellular proteolysis as well as adhesion, cellular proliferation, and migration, processes germane to the pathogenesis of lung injury and neoplasia. In previous studies, we found that uPA regulates cell surface fibrinolysis by regulating its own expression as well as that of the uPA receptor and plasminogen activator inhibitor-1. In this study, we found that uPA alters expression of the tumor suppressor protein p53 in Beas2B airway epithelial cells in both a time- and concentration-dependent manner. These effects do not require uPA catalytic activity because the amino-terminal fragment of uPA lacking catalytic activity was as potent as two chain active uPA. Single chain uPA also enhanced p53 expression to the same extent as intact two chain active uPA and the amino-terminal fragment. Pretreatment of cells with anti-beta1 integrin antibody blocked uPA-induced p53 expression. uPA-induced p53 expression occurs without increased p53 mRNA expression. However, uPA induced oncoprotein MDM2 in a concentration-dependent manner. uPA-induced p53 expression does not require activation of tyrosine kinases. Inactivation of protein-tyrosine phosphatase SHP-2 inhibits both basal and uPA-induced p53 expression. Plasmin did not alter uPA-mediated p53 expression. The induction of p53 expression by exposure of lung epithelial cells to uPA is a newly recognized pathway by which urokinase may influence the proliferation of lung epithelial cells. This pathway could regulate pathophysiologic alterations of p53 expression in the setting of lung inflammation or neoplasia. 相似文献
37.
Deepak Kurup Ajay Kumar Nagpal Shashit Shetty Tapan Kumar Mandal Juhi Anand Rajdeep Mitra 《Bioinformation》2021,17(1):67
It is of interest to document data on the push – out bond strength of three different root canal treatment sealers such as MTA Fillapex (MTA based), AH plus (Epoxy Resin based) and Apexit plus (Calcium hydroxide based). Forty-five freshly extracted human maxillary central incisors with closed apices were selected randomly. All the teeth were sectioned at cement-enamel junction using a diamond disc before starting the root canal preparation to obtain root length of 12 mm. All teeth were instrumented using ProTaper rotary instruments. 5.25% sodium hypochlorite was used for irrigation between instrumentation followed by 17% EDTA, and final rinse by saline. Obturation procedures were done using the gutta-percha single cone technique. 45 roots were randomly assigned to 3 groups of 15 for obturation with gutta-percha cones and 1 of the 3 sealers (n=15). Group 1 = MTA Fillapex sealer + gutta-percha: Group 2 = AH plus sealer + gutta-percha:Group 3 = Apexit plus sealer + gutta-percha. The roots were sectioned horizontally to its canal into 3 sections: Coronal, Mid-root and Apical-thirds using a precision cutting machine, with a thickness of 3 mm. The specimens were subjected to push-out test using a universal testing machine that carried a plunger. The loading speed was 1mm/min until the dislodgment of the material occurred. The independent t- test was used to compare the mean scores among the study groups. The level of significance was set at 5% for all tests. After the push-out bond strength test, each sample was evaluated under stereomicroscope (40x) to determine the mode of failure and recorded as one of the following categories: adhesive, cohesive or mixed. The observations thus obtained were subjected to statistical analysis using Student - t test. AH Plus showed significantly higher values than MTA Fillapex and Apexit plus (p < 0.05). Amongst the push-out bond strength AH Plus sealer showed significant difference from MTA Fillapex and Apexit plus groups. There was no significant difference between MTA Fillapex and Apexit plus however (p>0.05). Microscopic analysis displayed that the majority of the modes were cohesive failures for AH Plus, adhesive failures for MTA Fillapex and mixed failures for Apexit Plus. . Thus, AH Plus had the highest bond strength and MTA Fillapex had the lowest bond strength to root dentin. Mean push-out bond strength values were ranked as follows; AH Plus >Apexit Plus > MTA Fillapex. Microscopic analysis displayed that the majority of the modes were cohesive failures of AH Plus, adhesive failures for MTA Fillapex and mixed failures for Apexit Plus. 相似文献
38.
Tejesvi MV Mahesh B Nalini MS Prakash HS Kini KR Subbiah V Shetty HS 《Canadian journal of microbiology》2006,52(5):427-435
Endophytic fungi represent an interesting group of microorganisms associated with the healthy tissues of terrestrial plants. They represent a large reservoir of genetic diversity. Fungal endophytes were isolated from the inner bark segments of ethnopharmaceutically important medicinal tree species, namely Terminalia arjuna, Crataeva magna, Azadirachta indica, Holarrhena antidysenterica, Terminalia chebula, and Butea monosperma (11 individual trees), growing in different regions of southern India. Forty-eight fungal species were recovered from 2200 bark segments. Mitosporic fungi represented a major group (61%), with ascomycetes (21%) and sterile mycelia (18%) the next major groups. Species of Fusarium, Pestalotiopsis, Myrothecium, Trichoderma, Verticillium, and Chaetomium were frequently isolated. Exclusive fungal taxa were recovered from five of the six plant species considered for the study of endophytic fungi. Rarefaction indices for species richness indicated the highest expected number of species for bark segments were isolated from T. arjuna and A. indica (20 species each) and from C. magna (18 species). 相似文献
39.
Shetty V Nickens Z Testa J Hafner J Sinnathamby G Philip R 《Journal of Proteomics》2012,75(11):3270-3290
Platinum-based chemotherapy is widely used to treat various cancers including ovarian cancer. However, the mortality rate for patients with ovarian cancer is extremely high, largely due to chemo-resistant progression in patients who respond initially to platinum based chemotherapy. Immunotherapy strategies, including antigen specific vaccines, are being tested to treat drug resistant ovarian cancer with variable results. The identification of drug resistant specific tumor antigens would potentially provide significant improvement in effectiveness when combined with current and emerging therapies. In this study, using an immunoproteomics method based on iTRAQ technology and an LC-MS platform, we identified 952 MHC class I presented peptides. Quantitative analysis of the iTRAQ labeled MHC peptides revealed that cisplatin-resistant ovarian cancer cells display increased levels of MHC peptides derived from proteins that are implicated in many important cancer pathways. In addition, selected differentially presented epitope specific CTL recognize cisplatin-resistant ovarian cancer cells significantly better than the sensitive cells. These over-presented, drug resistance specific MHC class I associated peptide antigens could be potential targets for the development of immunotherapeutic strategies for the treatment of ovarian cancer including the drug resistant phenotype. 相似文献
40.
Schulze-Topphoff U Shetty A Varrin-Doyer M Molnarfi N Sagan SA Sobel RA Nelson PA Zamvil SS 《PloS one》2012,7(3):e33797
Laquinimod is a novel oral drug that is currently being evaluated for the treatment of relapsing-remitting (RR) multiple sclerosis (MS). Using the animal model for multiple sclerosis, experimental autoimmune encephalomyelitis (EAE), we examined how laquinimod promotes immune modulation. Oral laquinimod treatment reversed established RR-EAE and was associated with reduced central nervous system (CNS) inflammation, decreased Th1 and Th17 responses, and an increase in regulatory T cells (Treg). In vivo laquinimod treatment inhibited donor myelin-specific T cells from transferring EAE to naive recipient mice. In vivo laquinimod treatment altered subpopulations of myeloid antigen presenting cells (APC) that included a decrease in CD11c(+)CD11b(+)CD4(+) dendritic cells (DC) and an elevation of CD11b(hi)Gr1(hi) monocytes. CD11b(+) cells from these mice exhibited an anti-inflammatory type II phenotype characterized by reduced STAT1 phosphorylation, decreased production of IL-6, IL-12/23 and TNF, and increased IL-10. In adoptive transfer, donor type II monocytes from laquinimod-treated mice suppressed clinical and histologic disease in recipients with established EAE. As effects were observed in both APC and T cell compartments, we examined whether T cell immune modulation occurred as a direct effect of laquinimod on T cells, or as a consequence of altered APC function. Inhibition of Th1 and Th17 differentiation was observed only when type II monocytes or DC from laquinimod-treated mice were used as APC, regardless of whether myelin-specific T cells were obtained from laquinimod-treated or untreated mice. Thus, laquinimod modulates adaptive T cell immune responses via its effects on cells of the innate immune system, and may not influence T cells directly. 相似文献