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61.
Namita Mitra Ramneek Verma Amarjit Singh 《Proceedings of the National Academy of Sciences, India. Section B.》2013,83(1):53-58
Viral neoplasms in commercial poultry are mainly caused by members of two families with Marek’s disease virus (MDV) belonging to Herpesviridae and reticuloendotheliosis virus (REV), avian leukosis virus subgroups A to E and avian leukosis virus subgroup J (ALV-J) belonging to Retroviridae. This study was conducted to know the status of neoplasms caused by avian oncogenic viruses in commercial chickens. 25 blood samples were collected from a broiler breeder flock that appeared healthy but chickens from the flock on necropsy showed visceral tumours. PCR was employed on blood DNAs of these chickens for detection of avian oncogenic viruses which eventually detected the presence of multiple oncogenic virus infection in most birds. MDV specific primers that could differentiate between pathogenic and non-pathogenic serotype-1 virus detected MDV in four blood DNAs. REV could be detected from all the 25 blood DNAs and endogenous ALV was detected in 21 blood DNAs signifying the slow transforming nature of the retroviruses that may take months to perpetuate visible tumours. It was concluded that concurrent presence of multiple oncogenic viruses in the same bird is more common than the presence of single virus. Thus, for early disease control programs, this moderately simple PCR diagnostic technique can be utilized to identify the birds undergoing latent infection with avian oncogenic viruses. 相似文献
62.
Efficient insertion of genes into the mouse germ line via retroviral vectors. 总被引:10,自引:4,他引:10 下载免费PDF全文
H van der Putten F M Botteri A D Miller M G Rosenfeld H Fan R M Evans I M Verma 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(18):6148-6152
We present a general strategy for the efficient insertion of recombinant retroviral vector DNA into the mouse germ line via infection of preimplantation mouse embryos. Transgenic mice were generated that harbor a replication-competent recombinant retrovirus (delta Mo + Py M-MuLV) that lacks the Moloney murine leukemia virus (M-MuLV)-type enhancer sequence in the long terminal repeat (LTR). Instead, the LTR contains an enhancer element that permits polyoma virus F101 to grow in undifferentiated F9 embryonal carcinoma cells. Expression studies in different tissues of animals transgenic for delta Mo + Py M-MuLV indicate possibilities to target and modulate expression of retroviral recombinants in mice via their LTR enhancer sequences. In addition, 16 transgenic mice were generated that harbor proviral DNA of a defective recombinant retrovirus carrying a mutant dihydrofolate reductase gene. 相似文献
63.
64.
Background
Minimal access approaches to inguinal hernia repair have added to the ongoing debate over the “best groin hernia repair.” The present prospective randomized controlled trial was done to compare the totally extraperitoneal (TEP) and transabdominal preperitoneal (TAPP) techniques of laparoscopic inguinal hernia repair. 相似文献65.
Praveen Kumar Pandey Inder Pawar Sandeep Kumar Beniwal Raaghav R. Verma 《中华创伤杂志(英文版)》2016,19(1):56-58
A 33 years old female patient presented with posttraumatic pain in the right foot for which radiographs of the right foot was advised. No fracture was detected on radiographs and patient was managed conservatively on medications and posterior splint immobilization. We found coincidentally a short fourth metatarsal and an accessory navicular bone in the right foot radiographs. After 3 weeks of immobilization, she underwent mobilization of the right foot, weight bearing and intensive physiotherapy for 6 weeks. After two months of injury she was still complaining of pain on the plantar aspect of right foot which was diagnosed as metatarsalgia and operated on by excision of the neuroma present in the 3rd web space of the right foot. After surgery she was completely relieved of pain and could do activities well related to the right foot. 相似文献
66.
Dumont AS Dumont RJ McNeill JH Kassell NF Sutherland GR Verma S 《Neurosurgery》2003,52(3):653-60; discussion 659-60
OBJECTIVE: Diabetes profoundly alters vascular function and is a risk factor for cerebrovascular disease. Diabetes increases myogenic tone and decreases responsiveness to adenosine triphosphatase (ATP)-sensitive K(+) (K(ATP)) channel openers and endothelium-dependent vasodilators. The mechanism(s) by which diabetes impairs cerebrovascular function remain obscure. In the present study, the effects of the potent vasoactive peptide endothelin-1 on myogenic tone and endothelium-dependent and potassium channel-mediated vasodilation in middle cerebral arteries from diabetic and nondiabetic rats were investigated. METHODS: Twenty-eight Wistar rats were divided into four experimental groups (n = 7 per group): control (C), control treated with bosentan (an endothelin A/B receptor antagonist) (CB), diabetic (D), and diabetic bosentan-treated (DB). Diabetes was induced with streptozotocin (D and DB groups), after which chronic bosentan treatment was initiated (CB and DB groups). Middle cerebral arteries were mounted in a pressure myograph, and myogenic responses were recorded. In addition, endothelium-dependent and -independent responses and the effects of the K(ATP) channel opener pinacidil were examined. RESULTS: Cerebral arteries from the diabetic and nondiabetic rats constricted in response to graded pressure increases. Maximum myogenic responses (percent constriction at 60 mm Hg) were significantly greater in the D group (38 +/- 3% versus 25 +/- 3% in C; P < 0.02). The enhanced myogenic tone in the D group was completely prevented by bosentan treatment (DB, 23 +/- 5% versus D; P < 0.003) without an effect on the CB group. In addition, bosentan treatment improved endothelium-dependent vasomotion and improved K(ATP)-mediated vasodilation in the DB group (P < 0.001). CONCLUSION: These data describe, for the first time, the interaction between endothelin-1, myogenic tone, and endothelial function in diabetes. Chronic endothelin antagonism restores cerebrovascular function in this model of diabetes and has global implications for the management of cerebrovascular disease in diabetes. 相似文献
67.
68.
Hyperglycemia exaggerates ischemia-reperfusion-induced cardiomyocyte injury: reversal with endothelin antagonism 总被引:8,自引:0,他引:8
Verma S Maitland A Weisel RD Li SH Fedak PW Pomroy NC Mickle DA Li RK Ko L Rao V 《The Journal of thoracic and cardiovascular surgery》2002,123(6):1120-1124
OBJECTIVES: We have previously demonstrated an importance of endothelin-1 in diabetic patients undergoing bypass surgery. Recent evidence suggests that cardiomyocytes might also produce endothelin-1, which might directly impair myocyte contractility by increasing intracellular calcium levels. Because hyperglycemia is a potent stimulus of endothelin-1 production, we hypothesized that increased production, action, or both of endothelin-1 might be a mediator of direct cardiomyocyte injury in diabetes. Therefore we studied the effects of endothelin receptor blockers (BQ-123 and bosentan) on hyperglycemia-induced endothelin-1 production and cellular injury after ischemia-reperfusion. METHODS: Using a human ventricular heart cell model of simulated ischemia-reperfusion, we studied the effects of normoglycemia (5 mmol/L, 48 hours) and hyperglycemia (25 mmol/L, 48 hours) on cellular injury and endothelin-1 production. Furthermore, the effects of selective endothelin-A and mixed endothelin-A/B receptor antagonism (with BQ-123 and bosentan, respectively) were evaluated. RESULTS: Cellular injury, as assessed by means of trypan blue uptake, was higher in human ventricular heart cells subjected to hyperglycemia and simulated ischemia-reperfusion injury (P =.01); this effect was prevented with both BQ-123 and bosentan (P =.01). In addition, heart cells from the hyperglycemic group elaborated more endothelin-1 after ischemia-reperfusion (P =.02). CONCLUSIONS: Endothelin-1 production and cellular injury were greater in human ventricular heart cells subjected to hyperglycemic conditions and simulated ischemia-reperfusion. These effects are mediated by endothelin-A receptors because both BQ-123 and bosentan exerted similar degrees of protection. Endothelin receptor blockade is a novel strategy to improve the resistance of the diabetic heart to cardioplegic arrest and reperfusion. 相似文献
69.
Ursodeoxycholic Acid Enhances Fractional Calcium Absorption in Primary Biliary Cirrhosis 总被引:2,自引:0,他引:2
A. Verma J. D. Maxwell L. Ang T. Davis S. Hodges T. C. Northfield M. Zaidi M. Pazianas 《Osteoporosis international》2002,13(8):677-682
Bone disease is a frequently reported complication in primary biliary cirrhosis (PBC), but its pathogenesis is poorly understood.
Calcium malabsorption has been considered as an important contributing factor. Ursodeoxycholic acid (UDCA) is the treatment
of choice in PBC, improving survival, but its effect on calcium absorption is unknown. In this study, we have measured fractional
calcium absorption, using a single isotope method, in a group of female PBC patients (median age: 60 years, range: 46–78 years)
and age-matched female controls (median age: 58 years, range: 36–74). Bone mineral density (BMD) in PBC patients was significantly
lower than age-matched controls (g/cm2± SEM; lumbar spine: controls 1.139 ± 0.028, PBC patients 1.004 ± 0.026, p= 0.0028; femoral neck: controls 0.944 ± 0.034, PBC patients 0.819 ± 0.023, p = 0.0032). Twenty two PBC patients, who were not vitamin D-deficient, were off and on UDCA for ~1 month and ~8 weeks, respectively.
Fractional calcium absorption in PBC patients prior to UDCA treatment (mean ± SEM, 33.8 ± 2.6%) was significantly lower than
controls (52.0 ± 2.4%, p<0.001). Following UDCA therapy, fractional calcium absorption increased significantly (Off UDCA: 33.1 ± 2.6%, On UDCA: 36.6
± 2.5%, p<0.0058). Osteocalcin levels were significantly raised in the PBC group (mean ± SEM, ng/ml, 41.4 ± 2.02) compared to controls
(31.1 ± 2.64, p= 0.002). There were no differences in parathyroid hormone (PTH) or 25-hydroxyvitamin D levels between these two groups or
following UDCA therapy. In conclusion, we found that PBC patients display low spinal and femoral neck BMD, reduced fractional
calcium absorption, and elevated plasma osteocalcin. The calcium malabsorption is corrected partially by UDCA therapy. Long-term
studies are required to determine whether this effect can be sustained, and whether a sustained increase in fractional calcium
absorption can translate into a favorable change in bone strength in patients with PBC.
Received: 27 November 2001 / Accepted: 11 April 2002 相似文献
70.
Effect of highly purified capsaicin on articular cartilage and rotator cuff tendon healing: An in vivo rabbit study 下载免费PDF全文
Nicole A. Friel Allison G. McNickle Michael J. DeFranco FanChia Wang Elizabeth F. Shewman Nikhil N. Verma Brian J. Cole Bernard R. Bach Jr. Susan Chubinskaya Susan M. Kramer Vincent M. Wang 《Journal of orthopaedic research》2015,33(12):1854-1860
Highly purified capsaicin has emerged as a promising injectable compound capable of providing sustained pain relief following a single localized treatment during orthopedic surgical procedures. To further assess its reliability for clinical use, the potential effect of highly purified capsaicin on articular cartilage metabolism as well as tendon structure and function warrants clarification. In the current study, rabbits received unilateral supraspinatus transection and repair with a single 1 ml injection of capsaicin (R + C), PEG‐only placebo (R + P), or saline (R + S) into the glenohumeral joint (GHJ). An additional group received 1 ml capsaicin onto an intact rotator cuff (I + C). At 18 weeks post‐op, cartilage proteoglycan (PG) synthesis and content as well as cell viability were similar (p > 0.05) across treatment groups. Biomechanical testing revealed no differences (p > 0.05) among tendon repair treatment groups. Similarly, histologic features of both cartilage and repaired tendons showed minimal differences across groups. Hence, in this rabbit model, a single injection of highly purified capsaicin into the GHJ does not induce a deleterious response with regard to cartilage matrix metabolism and cell viability, or rotator cuff healing. These data provide further evidence supporting the use of injectable, highly purified capsaicin as a safe alternative for management of postoperative pain following GHJ surgery. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1854–1860, 2015. 相似文献