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排序方式: 共有1180条查询结果,搜索用时 15 毫秒
91.
Roussos ET Goswami S Balsamo M Wang Y Stobezki R Adler E Robinson BD Jones JG Gertler FB Condeelis JS Oktay MH 《Clinical & experimental metastasis》2011,28(6):515-527
Mena, an actin regulatory protein, functions at the convergence of motility pathways that drive breast cancer cell invasion and migration in vivo. The tumor microenvironment spontaneously induces both increased expression of the Mena invasive (Mena(INV)) and decreased expression of Mena11a isoforms in invasive and migratory tumor cells. Tumor cells with this Mena expression pattern participate with macrophages in migration and intravasation in mouse mammary tumors in vivo. Consistent with these findings, anatomical sites containing tumor cells with high levels of Mena expression associated with perivascular macrophages were identified in human invasive ductal breast carcinomas and called TMEM. The number of TMEM sites positively correlated with the development of distant metastasis in humans. Here we demonstrate that mouse mammary tumors generated from EGFP-Mena(INV) expressing tumor cells are significantly less cohesive and have discontinuous cell-cell contacts compared to Mena11a xenografts. Using the mouse PyMT model we show that metastatic mammary tumors express 8.7 fold more total Mena and 7.5 fold more Mena(INV) mRNA than early non-metastatic ones. Furthermore, Mena(INV) expression in fine needle aspiration biopsy (FNA) samples of human invasive ductal carcinomas correlate with TMEM score while Mena11a does not. These results suggest that Mena(INV) is the isoform associated with breast cancer cell discohesion, invasion and intravasation in mice and in humans. They also imply that Mena(INV) expression and TMEM score measure related aspects of a common tumor cell dissemination mechanism and provide new insight into metastatic risk. 相似文献
92.
Frances MF Goswami R Rachinsky M Craen R Kiviniemi AM Fleischhauer A Steinback CD Zamir M Shoemaker JK 《Experimental physiology》2011,96(11):1129-1137
This study tested the hypothesis that the compliance (C) and viscoelasticity (K) of the forearm vascular bed are controlled by myogenic and/or α-adrenergic receptor (αAR) activation. Heart rate (HR) and waveforms of brachial artery blood pressure (Finometer) and forearm blood flow (Doppler ultrasound) were measured in baseline conditions and during infusion of noradrenaline (NA; αAR agonist), with and without phentolamine (αAR antagonist; n = 10; 6 men and 4 women). These baseline and αAR-agonist-based measures were repeated when the arm was positioned above or below the heart to modify the myogenic stimulus. A lumped Windkessel model was used to quantify the values of forearm C and K in each set of conditions. Baseline forearm C was inversely, and K directly, related to the myogenic load (P < 0.001). Compared with saline infusion, C was increased, but K was unaffected, with phentolanine, but only in the 'above' position. Compliance was reduced (P < 0.001) and K increased (P = 0.06) with NA infusion (main effects of NA) across arm positions; phentolamine minimized these NA-induced changes in C and K for both arm positions. Examination of conditions with and without NA infusion at similar forearm intravascular pressures indicated that the NA-induced changes in C and K were due largely to the concurrent changes in blood pressure. Therefore, within the range of arm positions used, it was concluded that vascular stiffness and vessel wall viscoelastic properties are acutely affected by myogenic stimuli. Additionally, forearm vascular compliance is sensitive to baseline levels of αAR activation when transmural pressure is low. 相似文献
93.
Objective To study its effects on reproductive performance in albino rats.
Methods The chromatographic fraction (CF) of crude methanolic extract of the herb has been subcutaneously administered to female albino rats. Experiments were carried out in adult cyclic females and oavriectomised (OVX) females during early gestation period. Uterine horns were collected following the respective treatment regimen to stud), the protein profile in 15% gel SDS-PAGE.
Results The CF induced changes in the expression of protein in rat uterus. New proteins have been expressed in uterus of adult cyclic females having ovary in-situ. The OVX females treated with CF showed altered uterine protein profile compared with that of OVX control and OVX estradiol-17β (E2) treated rats. The CF exerted its effect on expression of uterine protein during early gestation period in rats. While uterine proteins of CF treated females were similar to that of controls during preimplantation period; many of the proteins on day 6 of gestation have been found either missing or expressed in lesser intensity.
Conclusion The root of Polygonum hydropiper contains potential compound(s) which can alter the reproductive performance of female rats modulating uterine protein expression. 相似文献
Methods The chromatographic fraction (CF) of crude methanolic extract of the herb has been subcutaneously administered to female albino rats. Experiments were carried out in adult cyclic females and oavriectomised (OVX) females during early gestation period. Uterine horns were collected following the respective treatment regimen to stud), the protein profile in 15% gel SDS-PAGE.
Results The CF induced changes in the expression of protein in rat uterus. New proteins have been expressed in uterus of adult cyclic females having ovary in-situ. The OVX females treated with CF showed altered uterine protein profile compared with that of OVX control and OVX estradiol-17β (E2) treated rats. The CF exerted its effect on expression of uterine protein during early gestation period in rats. While uterine proteins of CF treated females were similar to that of controls during preimplantation period; many of the proteins on day 6 of gestation have been found either missing or expressed in lesser intensity.
Conclusion The root of Polygonum hydropiper contains potential compound(s) which can alter the reproductive performance of female rats modulating uterine protein expression. 相似文献
94.
95.
Multiple sclerosis (MS) is a common autoimmune neurodegenerative disease of unknown cause, which results in inflammation and plaques of demyelination in brain and eventual axonal degeneration. We report the novel presence of oxidized phosphatidylcholine [1-palmitoyl-2-(5'-oxo)valeryl-sn-glycero-3-phosphorylcholine (POVPC)], a lipid associated with inflammatory diseases such as atherosclerosis and lung disease, in the brain of MS patients. The OxPC epitope was detected by Western blotting with the E06 monoclonal antibody. E06-positive lipid was present in the highest amounts in MS plaques, which also showed evidence of low-molecular-weight (15-kDa) OxPC-modified protein. E06 reactivity did not change with post-mortem interval, and E06-positive lipids were largely absent from control tissue. We then used a second monoclonal antibody (AB1-2, which recognizes the E06/T15 idiotype and therefore detects the presence of antibody to OxPC) to show that MS brain samples were strongly positive for the 50-kDa antibody heavy chain. We also showed that isoelectric focussing of the oligoclonal IgG characteristic of MS revealed some immunoglobulin bands that Western blotted with the AB1-2 antibody. Spinal cords from mice induced to undergo experimental allergic encephalomyelitis (EAE) also showed strong AB1-2 reactivity by both immunocytochemistry and Western blot analysis. We therefore conclude that we can detect both OxPC and 15-kDa protein modified by OxPC and the antibody to the antibody to OxPC (antiidiotype) in pathological tissue and suggest that this could play a role in the progression of MS. 相似文献
96.
Kathleen H. Corriveau Usha Goswami 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(1):119-130
In prior work (Corriveau et al., 2007), we showed that children with speech and language impairments (SLI) were significantly less sensitive than controls to two auditory cues to rhythmic timing, amplitude envelope rise time and duration. Here we explore whether rhythmic problems extend to rhythmic motor entrainment. Tapping in synchrony with a beat has been described as the simplest rhythmic act that humans perform. We explored whether tapping to a beat would be impaired in children for whom auditory rhythmic timing is impaired. Children with SLI were indeed found to be impaired in a range of measures of paced rhythmic tapping, but were not equally impaired in tapping in an unpaced control condition requiring an internally-generated rhythm. The severity of impairment in paced tapping was linked to language and literacy outcomes. 相似文献
97.
The aim of study was to evaluate the effect of commonly used lisinopril, rosuvastatin and their combined action on site-specific nephrotoxicity in rats using clusterin and microalbumin nephrotoxic biomarkers and other related parameters using oral gavage. Rosuvastatin at 2 different doses showed increase in urinary microalbumin levels whereas lisinopril and its combination with rosuvastatin at 2 different doses did not show urinary microalbumin excretion indicating beneficial effects of lisinopril in terms of reducing microalbumin. Urinary clusterin levels significantly increased in high-dose treated animals of lisinopril and rosuvastatin. The use of lisinopril plus rosuvastatin at low dose also led to worsened renal function by raising urinary clusterin levels (217 ± 4.6 ng/ml) when compared with the control (143 ± 3.3 ng/ml). Renal histopathology showed multifocal regeneration of tubules indicating proximal tubule damaged. These results indicate that lisinopril (50 mg/kg), rosuvastatin (100 mg/kg), lisinopril+rosuvastatin (20+40 mg/kg) and lisinopril+rosuvastatin (50+100 mg/kg) showed toxicity only on proximal tubules. 相似文献
98.
Atulya Iyengar Tuhin Subhra Chakraborty Sarit Pati Goswami Chun-Fang Wu Obaid Siddiqi 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(21):9855-9860
Olfactory responses of Drosophila undergo pronounced changes after eclosion. The flies develop attraction to odors to which they are exposed and aversion to other odors. Behavioral adaptation is correlated with changes in the firing pattern of olfactory receptor neurons (ORNs). In this article, we present an information-theoretic analysis of the firing pattern of ORNs. Flies reared in a synthetic odorless medium were transferred after eclosion to three different media: (i) a synthetic medium relatively devoid of odor cues, (ii) synthetic medium infused with a single odorant, and (iii) complex cornmeal medium rich in odors. Recordings were made from an identified sensillum (type II), and the Jensen–Shannon divergence (DJS) was used to assess quantitatively the differences between ensemble spike responses to different odors. Analysis shows that prolonged exposure to ethyl acetate and several related esters increases sensitivity to these esters but does not improve the ability of the fly to distinguish between them. Flies exposed to cornmeal display varied sensitivity to these odorants and at the same time develop greater capacity to distinguish between odors. Deprivation of odor experience on an odorless synthetic medium leads to a loss of both sensitivity and acuity. Rich olfactory experience thus helps to shape the ORNs response and enhances its discriminative power. The experiments presented here demonstrate an experience-dependent adaptation at the level of the receptor neuron. 相似文献
99.
Atherosclerosis pathophysiology and the role of novel risk factors: a clinicobiochemical perspective 总被引:1,自引:0,他引:1
Atherosclerosis is the root cause of the biggest killer of the 21st century. Mechanisms contributing to atherogenesis are multiple and complex. A number of theories-including the role of dyslipidemia, hypercoagulability, oxidative stress, endothelial dysfunction, and inflammation and infection by certain pathogens-have been propounded from time to time explain this complex phenomenon. Recently it has been suggested that atherosclerosis is a multifactorial, multistep disease that involves chronic inflammation at every step, from initiation to progression, and that all the risk factors contribute to pathogenesis by aggravating the underlying inflammatory process. A better understanding of the pathogenesis of atherosclerosis will aid in devising pharmaceutical and lifestyle modifications for reducing mortality resulting from coronary artery disease (CAD).A comprehensive literature search was conducted using the Web sites of the National Library of Medicine (http:// www.ncbl.nlm.nih.gov/) and PubMed Central, the US National Library of Medicine's digital archive of life sciences literature (http:// www.pubmedcentral.nih.gov/). The data were accessed from books and journals in which relevant articles in this field were published.The whole spectrum of coronary artery disease evolves through various events that lead to the formation and progression of atherosclerotic plaque and finally its complications. Atherosclerosis is the culprit behind coronary artery disease, cerebral vascular disease, and peripheral vascular disease. The pathogenic mechanisms are varied and complex. Of late, the role of lipoprotein (a), homocysteine, and inflammation and infection as prime culprits in pathogenesis of CAD is the subject of intense research and debate. The appreciation of the role of inflammation in atherosclerosis provides a mechanistic framework to understand the clinical benefits of newer therapeutic strategies, and a better understanding of pathogenesis aids in formulating preventive and therapeutic strategies in reducing mortality resulting from CAD.An in-depth knowledge of the various pathogenic mechanisms involved in atherosclerosis can help in substantiating the current existing knowledge about the CAD epidemic. This knowledge will help clinicians to better manage the disease, which affects Indians in its most severe form. 相似文献
100.