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71.
Kaul R Sivapurapu N Afzalpurkar A Srikanth V Govind CK Gupta SK 《Reproductive biomedicine online》2001,2(1):33-39
Zona pellucida (ZP) glycoproteins have been proposed as candidate antigens for development of immunocontraceptive vaccines. In this study, the efficacy to block fertility by immunization with recombinant bonnet monkey (Macaca radiata) zona pellucida glycoprotein-C (r-bmZPC) expressed in Escherichia coli and its synthetic peptide (P(4): KGDCGTPSHSRRQPHVVSQWSRSA, aa residues 324-347) conjugated to diphtheria toxoid (DT) has been evaluated in a homologous system. Female bonnet monkeys, immunized with P(4)-DT conjugate showed better immunocontraceptive potential as compared to an r-bmZPC-DT immunized group. In spite of high anti-P(4) antibody titres, animals continued to have ovulatory cycles and showed no disturbance in cyclicity (except summer amenorrhoea). No ovarian pathology was observed in the P(4) immunized group. These results suggest that immunization with the P(4) may lead to block in fertility without obvious ovarian dysfunction. However, further inputs are required to identify additional ZP based B-cell epitopes to enhance the contraceptive efficacy. 相似文献
72.
Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome in which affected individuals develop nervous system abnormalities that might reflect astrocyte dysfunction. The TSC2 gene product, tuberin, encodes a GTPase-activating protein (GAP) domain, which regulates the activity of Rap1 in vitro. To determine whether dysregulated Rap1, resulting from TSC2 inactivation, leads to increased astrocyte proliferation in vivo, we generated transgenic mice expressing activated Rap1(G12V) specifically in astrocytes. We observed no statistically significant difference in the number of astrocytes between wild-type and GFAP-Rap1(G12V) littermates in vivo; however, during log-phase growth, we observed a 25% increase in GFAP-Rap1(G12V) astrocyte doubling times compared to wild-type controls. This decreased proliferation was associated with delayed MAP kinase, but not AKT, activation. Lastly, to determine whether constitutive Rap1 activation could reverse the increased astrocyte proliferation observed in transgenic mice expressing oncogenic Ras(G12V), we generated transgenic mice expressing both Ras(G12V) and Rap1(G12V) in astrocytes. These double transgenic mice showed a striking reversion of the Ras(G12V) astrocyte growth phenotype. Collectively, these results argue that the tumor suppressor properties of tuberin are unlikely to be related to Rap1 inactivation and that Rap1 inhibits mitogenic Ras pathway signaling in astrocytes. 相似文献
73.
Antidepressant medication use before and after kidney transplant: implications for outcomes – a retrospective study 下载免费PDF全文
Krista L. Lentine Abhijit S. Naik Rosemary Ouseph Zidong Zhang David A. Axelrod Dorry L. Segev Vikas R. Dharnidharka Daniel C. Brennan Henry Randall Raj Gadi Ngan N. Lam Gregory P. Hess Bertram L. Kasiske Mark A. Schnitzler 《Transplant international》2018,31(1):20-31
We examined a novel database wherein national US transplant registry identifiers were linked to records from a large pharmaceutical claims warehouse (2008–2015) to characterize antidepressant use before and after kidney transplantation, and associations [adjusted hazard ratio (aHR) 95% CI] with death and graft failure. Among 72 054 recipients, 12.6% filled antidepressant medications in the year before transplant, and use was more common among women and patients who were white, unemployed, and had limited functional status. Pre‐transplant antidepressant use was associated with 39% higher 1‐year mortality (aHR 1.39, 95% CI 1.18–1.64) and 15% higher all‐cause graft loss risk (aHR 1.15, 95% CI 1.02–1.30). More than 50% of patients who filled antidepressants pre‐transplant continued fill post‐transplant. Antidepressant use in the first year after transplant was associated with twofold higher risk of death (aHR 1.94, 95% CI 1.60–2.35), 38% higher risk of death‐censored graft failure, and 61% higher risk of all‐cause graft failure in the subsequent year. Pre‐listing antidepressant use was also associated with increased mortality, but transplantation conferred a survival benefit regardless of prelisting antidepressant use status. While associations may in part reflect underlying behaviors or comorbidities, kidney transplant candidates and recipients treated with antidepressant medications should be monitored and supported to reduce the risk of adverse outcomes. 相似文献
74.
Virulence genes and neutral DNA markers of Helicobacter pylori isolates from different ethnic communities of West Bengal,India 总被引:3,自引:0,他引:3 下载免费PDF全文
Datta S Chattopadhyay S Balakrish Nair G Mukhopadhyay AK Hembram J Berg DE Rani Saha D Khan A Santra A Bhattacharya SK Chowdhury A 《Journal of clinical microbiology》2003,41(8):3737-3743
Virulence-associated genes and neutral DNA markers of Helicobacter pylori strains from the Santhal and Oroan ethnic minorities of West Bengal, India, were studied. These people have traditionally been quite separate from other Indians and differ culturally, genetically, and linguistically from mainstream Bengalis, whose H. pylori strains have been characterized previously. H. pylori was found in each of 49 study participants, although none had peptic ulcer disease, and was cultured from 31 of them. All strains carried the cag pathogenicity island and potentially toxigenic s1 alleles of vacuolating cytotoxin gene (vacA) and were resistant to at least 8 micro g of metronidazole per ml. DNA sequence motifs in vacA mid-region m1 alleles, cagA, and an informative insertion or deletion motif next to cagA from these strains were similar to those of strains from ethnic Bengalis. Three mobile elements, IS605, IS607, and ISHp608, were present in 29, 19, and 10%, respectively, of Santhal and Oroan strains, which is similar to their prevalence in Bengali H. pylori. Thus, there is no evidence that the gene pools of H. pylori of these ethnic minorities differ from those of Bengalis from the same region. This relatedness of strains from persons of different ethnicities bears on our understanding of H. pylori transmission between communities and genome evolution. 相似文献
75.
76.
Chetan V Kantharia R Y Prabhu A N Dalvi Abhijit Raut R D Bapat Avinash N Supe 《Tropical gastroenterology》2007,28(3):105-108
BACKGROUND AND AIMS: Pancreatic trauma is associated with high morbidity and mortality. Diagnosis is often difficult and surgery poses a formidable challenge. METHOD: Data from 17 patients of pancreatic trauma gathered from a prospectively maintained database were analysed and the following parameters were considered: mode of injury, diagnostic modalities, associated injury, grade of pancreatic trauma and management. Pancreatic trauma was graded from I through IV, as per Modified Lucas Classification. RESULTS: The median age was 39 years (range 19-61). The aetiology of pancreatic trauma was blunt abdominal trauma in 14 patients and penetrating injury in 3. Associated bowel injury was present in 4 cases (3 penetrating injury and 1 blunt trauma) and 1 case had associated vascular injury. 5 patients had grade I, 3 had grade II, 7 had grade III and 2 had grade IV pancreatic trauma. Contrast enhanced computed tomography scan was used to diagnose pancreatic trauma in all patients with blunt abdominal injury. Immediate diagnosis could be reached in only 4 (28.5%) patients. 7 patients responded to conservative treatment. Of the 10 patients who underwent surgery, 6 required it for the pancreas and the duodenum. (distal pancreatectomy with splenectomy-3, pylorus preserving pancreatoduodenectomy-1, debridement with external drainage-1, associated injuries-duodenum-1). Pancreatic fistula, recurrent pancreatitis and pseudocyst formation were seen in 3 (17.05%), 2 (11.7%) and 1 (5.4%) patient respectively. Death occurred in 4 cases (23.5%), 2 each in grades III and IV pancreatic trauma. CONCLUSIONS: Contrast enhanced computed tomography scan is a useful modality for diagnosing, grading and following up patients with pancreatic trauma. Although a majority of cases with pancreatic trauma respond to conservative treatment, patients with penetrating trauma, and associated bowel injury and higher grade pancreatic trauma require surgical intervention and are also associated with higher morbidity and mortality. 相似文献
77.
Pradeep Vaideeswar M.D. Arivarasan Karunamurthy M.D. Anil M. Patwardhan M.D. M.Ch. † Priya Hira M.D. ‡ Abhijit R. Raut M.D. ‡ 《Journal of cardiac surgery》2010,25(1):32-35
Abstract Cardiac calcified amorphous tumor is a rare pseudoneoplastic intracavitary mass composed of calcium deposits in a background of amorphous degenerating fibrin. We report occurrence of this lesion in the right atrium in two male patients. These were accompanied by calcific occlusion of the inferior vena cava and right pulmonary artery. (J Card Surg 2010;25:32-35) 相似文献
78.
Background
There is very limited literature on alcohol use among the elderly and little is known about the impact it has on family and caregivers, especially in low and middle income countries.Aim
To estimate the independent effect of heavy alcohol use among the elderly on the psychological health of their co-residents.Methods
This is a secondary analysis using data from the comprehensive cross-sectional survey of the 10/66 dementia research group population-based research programme in the Dominican Republic. The characteristics of the elderly participants as well as the co-residents were described. The independent association of heavy drinking among the participants with psychological morbidity in their co-residents was estimated. Different models were generated to rule out potential mediating effects of disability and behavioural symptoms.Results
Prevalence of heavy alcohol use in the elderly in Dominican Republic was 10.6%. There was a statistically significant independent effect of heavy alcohol use by the elderly on their co-residents mental health (PR = 1.47; 95% CI 1.07-2.01) which was not accounted by disability (Sobel-Goodman test, p = 0.15). Severity of psychological and behavioural symptoms partially (29.1% of the total effect) explained this association (Sobel-Goodman mediation test, p = 0.006).Conclusions
Health services for the elderly in low and middle income countries will have to be configured around detection of alcohol problems among the elderly as well as offering appropriate support to their co-residents. 相似文献79.
Gormley AJ Greish K Ray A Robinson R Gustafson JA Ghandehari H 《International journal of pharmaceutics》2011,415(1-2):315-318
Plasmonic photothermal therapy (PPTT) with gold nanostructures has been used to generate significant heat within tumors to ablate vasculature. Here we report the use of gold nanorod (GNR) mediated PPTT to induce moderate hyperthermia as a tool to enhance the delivery of macromolecules. GNRs were injected intravenously in a mouse sarcoma (S-180) tumor model. After 24h Evans blue dye (EBD) was injected and the right tumor was radiated with a laser diode for 10 min. EBD content in the right and left tumors were extracted in formamide, measured spectrophotometrically and expressed as a thermal enhancement ratio (TER). Enhanced delivery of EBD was observed (up to 1.8-fold) when tumor temperatures reached 43°C or 46°C. No statistical difference was observed between tumors at these two temperatures, though significant hemorrhage was observed in tumors and surrounding areas receiving the higher thermal dose (46°C). These results indicate that tumor directed PPTT may be used to induce moderate hyperthermia and therefore selectively increase the delivery of macromolecules with therapeutic anticancer drugs. 相似文献
80.
Cytochrome P450 (CYP450) has widely been implicated for drug-drug interactions (DDI) in the pharmaceutical industry. Inhibition or induction of this enzyme family has led to withdrawal of multiple drugs from the market leading to major time and financial losses for the pharmaceutical industry. CYP450 plays a prevailing role in the biotransformation of a large number of structurally diverse drugs. Few isoenzymes of the CYP enzyme family (CYP3A4, 2D6 and 2C9 family) are mainly involved in metabolism of most of the drugs. To avoid such interactions and potentially minimize DDI, major pharmaceutical organizations prefer to incorporate CYP enzyme screening at an early stage of their discovery program. While this has been a prevalent practice in the pharmaceutical industry lately, there is very limited literature available reviewing the relationship between chemotypes and CYP isoforms. This review will collate literature pertaining to CYP-inhibition modulation through physicochemical parameters and chemical modification and thus bring to focus commonly used trends by medicinal chemists world-wide. 相似文献