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91.
Mahesh C. Karamchandani M.D. Dr. Robert Riether M.D. James Sheets M.D. John Stasik M.D. Lester Rosen M.D. Indru Khubchandani M.D. 《Diseases of the colon and rectum》1986,29(11):747-749
A patient with nephrocolic fistula secondary to perinephric abscess was treated successfully with nephrectomy, colonic resection,
and colocolostomy.
Supported in part by the Dorothy Rider Pool Health Care Trust Fund. 相似文献
92.
93.
Ayyappan Anitha Ismail Thanseem Kazuhiko Nakamura Mahesh M. Vasu Kazuo Yamada Takatoshi Ueki Yoshimi Iwayama Tomoko Toyota Kenji J. Tsuchiya Yasuhide Iwata Katsuaki Suzuki Toshiro Sugiyama Masatsugu Tsujii Takeo Yoshikawa Norio Mori 《Journal of psychiatry & neuroscience : JPN》2014,39(5):294-303
Background
In a genome-wide association study of autism, zinc finger protein 804A (ZNF804A) single nucleotide polymorphisms (SNPs) were found to be nominally associated in verbally deficient individuals with autism. Zinc finger protein 804A copy number variations (CNVs) have also been observed in individuals with autism. In addition, ZNF804A is known to be involved in theory of mind (ToM) tasks, and ToM deficits are deemed responsible for the communication and social challenges faced by individuals with autism. We hypothesized that ZNF804A could be a risk gene for autism.Methods
We examined the genetic association and CNVs of ZNF804A in 841 families in which 1 or more members had autism. We compared the expression of ZNF804A in the postmortem brains of individuals with autism (n = 8) and controls (n = 13). We also assessed in vitro the effect of ZNF804A silencing on the expression of several genes known to be involved in verbal efficiency and social cognition.Results
We found that rs7603001 was nominally associated with autism (p = 0.018). The association was stronger (p = 0.008) in the families of individuals with autism who were verbally deficient (n = 761 families). We observed ZNF804A CNVs in 7 verbally deficient boys with autism. In ZNF804A knockdown cells, the expression of synaptosomal-associated protein, 25kDa (SNAP25) was reduced compared with controls (p = 0.009). The expression of ZNF804A (p = 0.009) and SNAP25 (p = 0.009) were reduced in the anterior cingulate gyrus (ACG) of individuals with autism. There was a strong positive correlation between the expression of ZNF804A and SNAP25 in the ACG (p < 0.001).Limitations
Study limitations include our small sample size of postmortem brains.Conclusion
Our results suggest that ZNF804A could be a potential candidate gene mediating the intermediate phenotypes associated with verbal traits in individuals with autism. 相似文献94.
Mahesh P Kate Mikkel B Hansen Kim Mouridsen Leif ?stergaard Victor Choi Bronwen E Gould Rebecca McCourt Michael D Hill Andrew M Demchuk Shelagh B Coutts Dariush Dowlatshahi Derek J Emery Brian H Buck Kenneth S Butcher 《Journal of cerebral blood flow and metabolism》2014,34(1):81-86
Blood pressure (BP) reduction after intracerebral hemorrhage (ICH) is controversial, because of concerns that this may cause critical reductions in perihematoma perfusion and thereby precipitate tissue damage. We tested the hypothesis that BP reduction reduces perihematoma tissue oxygenation.Acute ICH patients were randomized to a systolic BP target of <150 or <180 mm Hg. Patients underwent CT perfusion (CTP) imaging 2 hours after randomization. Maps of cerebral blood flow (CBF), maximum oxygen extraction fraction (OEFmax), and the resulting maximum cerebral metabolic rate of oxygen (CMRO2max) permitted by local hemodynamics, were calculated from raw CTP data.Sixty-five patients (median (interquartile range) age 70 (20)) were imaged at a median (interquartile range) time from onset to CTP of 9.8 (13.6) hours. Mean OEFmax was elevated in the perihematoma region (0.44±0.12) relative to contralateral tissue (0.36±0.11; P<0.001). Perihematoma CMRO2max (3.40±1.67 mL/100 g per minute) was slightly lower relative to contralateral tissue (3.63±1.66 mL/100 g per minute; P=0.025). Despite a significant difference in systolic BP between the aggressive (140.5±18.7 mm Hg) and conservative (163.0±10.6 mm Hg; P<0.001) treatment groups, perihematoma CBF was unaffected (37.2±11.9 versus 35.8±9.6 mL/100 g per minute; P=0.307). Similarly, aggressive BP treatment did not affect perihematoma OEFmax (0.43±0.12 versus 0.45±0.11; P=0.232) or CMRO2max (3.16±1.66 versus 3.68±1.85 mL/100 g per minute; P=0.857). Blood pressure reduction does not affect perihematoma oxygen delivery. These data support the safety of early aggressive BP treatment in ICH. 相似文献
95.
Mahesh Ramalingam Sung-Jin Kim 《Journal of neural transmission (Vienna, Austria : 1996)》2014,121(6):611-626
Insulin, a pancreatic hormone, is best known for its peripheral effects on the metabolism of glucose, fats and proteins. There is a growing body of evidence linking insulin action in the brain to neurodegenerative diseases. Insulin present in central nervous system is a regulator of central glucose metabolism nevertheless this glucoregulation is not the main function of insulin in the brain. Brain is known to be specifically vulnerable to oxidative products relative to other organs and altered brain insulin signaling may cause or promote neurodegenerative diseases which invalidates and reduces the quality of life. Insulin located within the brain is mostly of pancreatic origin or is produced in the brain itself crosses the blood-brain barrier and enters the brain via a receptor-mediated active transport system. Brain Insulin, insulin receptor and insulin receptor substrate-mediated signaling pathways play important roles in the regulation of peripheral metabolism, feeding behavior, memory and maintenance of neural functions such as neuronal growth and differentiation, neuromodulation and neuroprotection. In the present review, we would like to summarize the novel biological and pathophysiological roles of neuronal insulin in neurodegenerative diseases and describe the main signaling pathways in use for therapeutic strategies in the use of insulin to the cerebral tissues and their biological applications to neurodegenerative diseases. 相似文献
96.
Radhakrishnan Mahesh Arghya Kusum Dhar Ankur Jindal Shvetank Bhatt 《Chemical biology & drug design》2014,83(5):583-591
A series of novel 1,8‐naphthyridine‐3‐carboxamides as 5‐HT3 receptor antagonists were synthesized with an intention to explore the antidepressant activity of these compounds. The title carboxamides were designed using ligand‐based approach keeping in consideration the structural requirement of the pharmacophore of 5‐HT3 receptor antagonists. The compounds were synthesized using appropriate synthetic route from the starting material nicotinamide. 5‐HT3 receptor antagonism of all the compounds, which was denoted in the form of pA2 value, was determined in longitudinal muscle myenteric plexus preparation from guinea‐pig ileum against 5‐HT3 agonist, 2‐methyl‐5‐HT. Compound 8g (2‐methoxy‐1, 8‐naphthyridin‐3‐yl) (2‐methoxy phenyl piperazine‐1‐yl) methanone was identified as the most active compound, which expressed a pA2 value of 7.67. The antidepressant activity of all the compounds was examined in mice model of forced swim test (FST); importantly, none of the compounds was found to cause any significant changes in the locomotor activity of mice at the tested dose levels. In FST, the compounds with considerably higher pA2 value exhibited promising antidepressant‐like activity, whereas compounds with lower pA2 value did not show antidepressant‐like activity as compared to the control group. 相似文献
97.
Introduction
The objective of the present investigation was to develop and evaluate mucoadhesive in situ film forming periodontal drug delivery system (MIFPDDS) for local delivery of chemotherapeutic agents. Ethyl cellulose, a film forming release retardant, was used in combination with Eudragit RL100, a mucoadhesive polymer, and polyvinylpyrrolidone K-30 to develop MIFPDDS.Materials and methods
A simplex lattice design was employed to achieve an optimum solvent blend (N-methyl-2-pyrrolidone, polyethylene glycol-200, and propylene glycol) which has rapid film formation capacity and low viscosity. The prepared MIFPDDS was evaluated for various parameters such as in vitro film forming capacity, viscosity, in vitro diffusion study, ex vivo mucoadhesion study, stability study, and compatibility. A 32 full-factorial design was used to investigate the influence of formulation variables.Results and discussion
Drug release data from all formulations were fitted to different kinetic models, and the Korsmeyer–Peppas model was found the best fit model. Increasing the concentration of each polymeric component increases viscosity, and time for 50, 70, and 90 % drug release was observed and graphically represented by the surface response and contour plots. The formulation of batches MIF1—PCM4, MIF6, and MIF7 failed to give the desired results for the first hour drug release and MIF8 and MIF9 failed to show viscosity below 70 cPs.Conclusion
The formulation of batch MIF5 containing 3 % (w/v) of ethyl cellulose and 8 % (w/v) of Eudragit RL100 was considered as optimum formulation. 相似文献98.
Christopher B. Anderson Michael Lipsky Subhadra V. Nandula Christopher E. Freeman Thomas Matthews Caitlin E. Walsh Gen Li Matthias Szabolcs Mahesh M. Mansukhani James M. McKiernan Vundavalli V. Murty 《Genes, chromosomes & cancer》2020,59(1):6-12
The cytogenetic alterations in renal oncocytoma (RO) are poorly understood. We analyzed 130 consecutive RO for karyotypic alterations. Clonal chromosome abnormalities were identified in 63 (49%) cases, which could be categorized into three classes of mutually exclusive cytogenetic categories. Class 1 (N = 20) RO had diploid karyotypes with characteristic 11q13 rearrangement in balanced translocations with 10 or more different chromosome partners in all cases. We identified recurrent translocation partners at 5q35, 6p21, 9p24, 11p13‐14, and 11q23, and confirmed that CCND1 gene rearrangement at 11q13 utilizing fluorescence in situ hybridization (FISH). Class 2 RO (N = 25) exhibited hypodiploid karyotypes with loss of chromosome 1 and/or losses of Y in males and X in females in all cases. The class 3 tumors comprising of 18 cases showed diverse types of abnormalities with the involvement of two or more chromosomes exclusive of abnormalities seen in classes 1 and 2 tumors. Furthermore, karyotypically uninformative cases were subjected to FISH analysis to identify classes 1 and 2 abnormalities. In this group, we found similar frequencies of CCND1 rearrangement, loss of chromosome 1 or Y as with karyotypically abnormal cases. We validated our results against 91 tumors from the Mitelman database. Correlation of clinical data with all the three classes of ROs showed no clear evidence of overall patient survival. Our findings support the hypothesis that RO exhibit three principal cytogenetic categories, which may have different roles in initiation and/or progression. These cytogenetic markers provide a key tool in the diagnostic evaluation of RO. 相似文献
99.
Aljawhara H. Almuqrin Jagannath Gangareddy Mahesh M. Hivrekar A. G. Pramod M. I. Sayyed K. Keshavamurthy Naseem Fatima K. M. Jadhav 《Materials》2022,15(6)
Strong nonlinear absorption (NLA), reduced optical limiting (OL) thresholds, and high radiation shielding parameters are required for the effective use of glasses in the laser radiation and nuclear radiation protecting materials. In view of this, the efficacy of Sm2O3 on the nonlinear optical (NLO) and OL properties were ascertained (at 532 nm) along with radiation shielding characteristics. The open and closed aperture Z-scan profiles revealed the presence of positive NLA and nonlinear refraction (NLR) phenomena respectively. OL measurements showed the existence of limiting behavior in the studied glasses. The NLA and NLR coefficients were improved while the OL thresholds were decreased as the doping of Sm2O3 elevated to a higher doping level. These improvements in NLA, NLR coefficients and OL efficiencies were attributed to the non-bridging oxygens and high polarizable Sm3+ ions. The NLA and OL results clearly suggest the high (5 mol %) Sm2O3 doped glass (Sm5CNLB) glass is beneficial to protect the delicate devices and human eye by suppressing the high energy laser light. The theoretical linear attenuation coefficients (LAC) values of the presented SmxCNLB glasses were obtained with the help of Phy-X software between 0.284 and 1.333 MeV. At 0.284 MeV, the maximum values occur and take values between 0.302 (for Sm0CNLB) and 0.409 cm−1 (for Sm5CNLB). We found that the LAC for the presented SmxCNLB glasses is a function of Sm2O3 content, where the LAC tends to increase, corresponding to the high probabilities of interaction, as the content of Sm2O3 changes from 0 to 5 mol %. The effective atomic number (Zeff) for the presented SmxCNLB glasses was examined between 0.284 and 1.333 MeV. As the amount of Sm2O3 is added, the Zeff increases, and this was observed at any energy. 相似文献
100.