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111.
Expression of microRNA‐155 correlates positively with the expression of Toll‐like receptor 7 and modulates hepatitis B virus via C/EBP‐β in hepatocytes
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112.
Major thrombocytopenia after balloon‐expandable transcatheter aortic valve replacement: Prognostic implications and comparison to surgical aortic valve replacement
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113.
Manouchehr S Vafaee Albert Gjedde Nasrin Imamirad Kim Vang Mallar M Chakravarty Jason P Lerch Paul Cumming 《Journal of cerebral blood flow and metabolism》2015,35(4):699-705
Acute nicotine administration stimulates [14C]deoxyglucose trapping in thalamus and other regions of rat brain, but acute effects of nicotine and smoking on energy metabolism have rarely been investigated in human brain by positron emission tomography (PET). We obtained quantitative PET measurements of cerebral blood flow (CBF) and metabolic rate of oxygen (CMRO2) in 12 smokers who had refrained from smoking overnight, and in a historical group of nonsmokers, testing the prediction that overnight abstinence results in widespread, coupled reductions of CBF and CMRO2. At the end of the abstention period, global grey-matter CBF and CMRO2 were both reduced by 17% relative to nonsmokers. At 15 minutes after renewed smoking, global CBF had increased insignificantly, while global CMRO2 had increased by 11%. Regional analysis showed that CMRO2 had increased in the left putamen and thalamus, and in right posterior cortical regions at this time. At 60 and 105 minutes after smoking resumption, CBF had increased by 8% and CMRO2 had increased by 11-12%. Thus, we find substantial and global impairment of CBF/CMRO2 in abstaining smokers, and acute restoration by resumption of smoking. The reduced CBF and CMRO2 during acute abstention may mediate the cognitive changes described in chronic smokers. 相似文献
114.
Suresh Govatati Kiran Challa Sunita B. Reddy Kayathi Pramod Mamata Deenadayal Baidyanath Chakravarty Sisinthy Shivaji Manjula Bhanoori 《Journal of assisted reproduction and genetics》2015,32(2):277-285
Purpose
To investigate the role of genetic variations and expression alterations of BRCA1 and BRCA2 genes in the pathophysiology of endometriosis.Methods
A genetic association study was conducted in 573 endometriosis cases and 490 controls of Indian origin. We genotyped 13 selected promoter SNPs of BRCA1 gene and 2 selected promoter SNPs of BRCA2 gene by PCR-sequencing analysis. In addition, to better understand genetic contributions to the pathophysiology of endometriosis, the expression pattern of BRCA1 & 2 was analyzed in the eutopic endometria of endometriosis cases and controls by western-blot and immunohistochemical analysis.Results
Our results revealed significant association between BRCA1 rs71361504 (−/GTT) SNP and endometriosis risk in Indian women (P < 0.0001), while the remaining SNPs of both BRCA1 & 2 genes showed no difference between cases and controls. Western-blot and immunohistochemical analysis revealed significantly decreased BRCA1 expression levels in eutopic endometria of patients compared with controls (P < 0.05). Furthermore, nuclear BRCA1 was frequently lost compared with cytoplasmic BRCA1 in eutopic endometria of patients. Expression of BRCA2 did not differ between patients and controls.Conclusions
BRCA1 rs71361504 SNP may modify the endometriosis risk in Indian women. In addition, decreased expression of BRCA1 may play an important role in the pathophysiology of endometriosis. The analysis of BRCA1 genetic variants and/or expression might help to identify patients at high risk for disease outcome.Electronic supplementary material
The online version of this article (doi:10.1007/s10815-014-0379-9) contains supplementary material, which is available to authorized users. 相似文献115.
Invariant natural killer T cells in lupus patients promote IgG and IgG autoantibody production
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Lei Shen Hong Zhang Maria Caimol Claudia J. Benike Eliza F. Chakravarty Samuel Strober Edgar G. Engleman 《European journal of immunology》2015,45(2):612-623
IgG autoantibodies, including antibodies to double‐stranded DNA (dsDNA), are pathogenic in systemic lupus erythematosus (SLE), but the mechanisms controlling their production are not understood. To assess the role of invariant natural killer T (iNKT) cells in this process, we studied 44 lupus patients. We took advantage of the propensity of PBMCs from patients with active disease to spontaneously secrete IgG in vitro. Despite the rarity of iNKT cells in lupus blood (0.002–0.05% of CD3‐positive T cells), antibody blockade of the conserved iNKT TCR or its ligand, CD1d, or selective depletion of iNKT cells, inhibited spontaneous secretion of total IgG and anti‐dsDNA IgG by lupus PBMCs. Addition of anti‐iNKT or anti‐CD1d antibody to PBMC cultures also reduced the frequency of plasma cells, suggesting that lupus iNKT cells induce B‐cell maturation. Like fresh iNKT cells, expanded iNKT‐cell lines from lupus patients, but not healthy subjects, induced autologous B cells to secrete antibodies, including IgG anti‐dsDNA. This activity was inhibited by anti‐CD40L antibody, as well as anti‐CD1d antibody, confirming a role for CD40L‐CD40 and TCR‐CD1d interactions in lupus iNKT‐cell‐mediated help. These results reveal a critical role for iNKT cells in B‐cell maturation and autoantibody production in patients with lupus. 相似文献
116.
Nirav H. Amin Anna Katsman Rajit Chakravarty Susan Harding Douglas L. Cerynik 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2012,22(8):703-707
Intramedullary fixation is the mainstay of treatment for femur fractures in the adult trauma population. With subtrochanteric fractures, accurate reduction and stable fixation become technically challenging. Adjuvant blocking screws in the proximal fragment can effectively be used to prevent varus and apex anterior malalignment when intramedullary nails are used in these fractures. Blocking screws decrease the canal volume, thereby allowing the intramedullary device to control the proximal segment. This aids in improving alignment between the proximal and distal fragments during reduction. We review the cases of six patients with proximal femur fractures who were treated with intramedullary nailing in conjunction with the placement of blocking screws. 相似文献
117.
Mehta Poonam Singh Priyamvada Gupta Nalini J. Sankhwar Satya Narayan Chakravarty Baidyanath Thangaraj Kumarasamy Rajender Singh 《Journal of assisted reproduction and genetics》2021,38(7):1871-1878
Journal of Assisted Reproduction and Genetics - To identify the contribution of mutations in the Desert Hedgehog (DHH) gene to the disorders of sexual differentiation (DSD) and male infertility.... 相似文献
118.
Megan E. B. Clowse Eliza Chakravarty Karen H. Costenbader Christina Chambers Kaleb Michaud 《Arthritis care & research》2012,64(5):668-674
Objective
Women with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) have fewer children on average than other women. We sought to determine the roles of infertility, pregnancy loss, and personal choice on family size in women with these diseases.Methods
A reproductive history questionnaire was completed by women with RA and SLE participating in a longitudinal observational study. Within each disease cohort, participants were divided into 3 groups: those interested in having children at symptom onset who had either fewer children than planned (group A) or the same number as planned (group B), and those no longer interested in having children at diagnosis (group C).Results
Of the 578 RA and 114 SLE women surveyed, >60% were in group C. Of those interested in having children, 55% with RA and 64% with SLE had fewer children than originally planned. Among women with RA, group A had 1 less pregnancy, 1 less live birth, and an infertility rate 1.5 times higher than group B; the miscarriage rate was similar in both groups. Compared to SLE group B, SLE group A had a similar number of pregnancies, but a 3‐fold higher rate of miscarriage and 1 less live birth. Concerns about child health and personal welfare were associated with a lower pregnancy rate.Conclusion
In this population, more than one‐half of young women with RA or SLE had fewer biologic children than desired. While patient choice plays a role, infertility in RA patients and miscarriage in SLE patients are also important. 相似文献119.
120.
Electrochemical separation techniques are not widely used in radionuclide generator technology and only a few studies have been reported [1-4]. Nevertheless, this strategy is useful when other parent-daughter separation techniques are not effective or not possible. Such situations are frequent when low specific activity (LSA) parent radionuclides are used for instance with adsorption chromatographic separations, which can result in lower concentration of the daughter radionuclide in the eluent. In addition, radiation instability of the column matrix in many cases can affect the performance of the generator when long lived parent radionuclides are used. Intricate knowledge of the chemistry involved in the electrochemical separation is crucial to develop a reproducible technology that ensures that the pure daughter radionuclide can be obtained in a reasonable time of operation. Crucial parameters to be critically optimized include the applied potential, choice of electrolyte, selection of electrodes, temperature of electrolyte bath and the time of electrolysis in order to ensure that the daughter radionuclide can be reproducibly recovered in high yields and high purity. The successful electrochemical generator technologies which have been developed and are discussed in this paper include the (90)Sr/(90)Y, (188)W/(188)Re and (99)Mo/(99m)Tc generators. Electrochemical separation not only acts as a separation technique but also is an effective concentration methodology which yields high radioactive concentrations of the daughter products. The lower consumption of reagents and minimal generation of radioactive wastes using such electrochemical techniques are compatible with 'green chemistry' principles. 相似文献