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61.
Increased expression of transferrin receptors and iron in amoeboid microglial cells in postnatal rats following an exposure to hypoxia 总被引:2,自引:0,他引:2
This study was aimed to ascertain the effects of hypoxia on regulation of iron in the brain of newborn rats. At 3 h and 1 day after hypoxic exposure transferrin receptor expression as detected immunohistochemically with the antibody OX-26, and the iron content as shown by Perls' staining of amoeboid microglial cells was markedly increased. The induced changes, however, were not evident at 10 min and in longer surviving rats killed at 3 and 7 days. It is suggested that the upregulation of transferrin receptor expression coupled with iron uptake by amoeboid microglial cells in the periventricular regions is a protective mechanism to facilitate the sequestration of excess iron that may have been released either from the iron-rich oligodendrocytes, or accumulated due to a disruption of its normal transportation following the hypoxic insult. This would help protect the brain from harmful effects of iron. 相似文献
62.
63.
Kamaljit Kaur Nishi Sonkhya A. S. Bapna 《Indian journal of otolaryngology and head and neck surgery》2003,55(1):21-24
Traditionally, it has been accepted that chronic suppurative Otitis media is associated with a breakdown in meekanical conduction
of sound leading to conductive hearing loss, On;the contrary, there are two schools of thought when it come, to the issue
of cpchlear involvement leading to sensorineural hearing loss (SNIIL) in chronic suppura the Otitis media. The present study
was undertaken to find out whether a sensorineural component exists in hearing loss associated with chronic suppurative otitis
media, A sample of 100 patients of unilateral chronic suppurative otitis media was selected for the Study and their bone conduction
thresholds Mere analyzed in relation to the duration of disease using audiometric data. A 24 per cent incidence of sensoineural
hearing loss was found in this series, garticularly involving the higher frequencies. Moreover, the incidence of sensorineural
hearing loss progressively increased with the increase in duration of chonic suppurative Ouns meadia 相似文献
64.
Gurmeet Kaur Dorina Belotti Angelika M Burger Kirsten Fisher-Nielson Patrizia Borsotti Elena Riccardi Jagada Thillainathan Melinda Hollingshead Edward A Sausville Raffaella Giavazzi 《Clinical cancer research》2004,10(14):4813-4821
PURPOSE: The purpose of this study was to investigate the antiangiogenic properties of 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG; NSC707545), a water-soluble benzoquinone ansamycin. EXPERIMENTAL DESIGN: The activity of 17-DMAG, in vivo, was evaluated for inhibition of fibroblast growth factor (FGF)-2-induced angiogenesis in s.c. implanted Matrigel in mice. In vitro, the activity of 17-DMAG on endothelial cells (human umbilical vein endothelial cells; HUVEC) was tested in FGF-2; and vascular endothelial growth factor (VEGF)-induced proliferation and apoptosis, motility, and extracellular matrix invasion; and on the alignment of capillary like structures in Matrigel. The protein level of heat shock protein (Hsp)90 and client proteins was examined by Western blot in FGF-2 and VEGF-stimulated HUVEC. RESULTS: Daily oral administration of 17-DMAG affected the angiogenic response in Matrigel in a dose-dependent manner. The hemoglobin content in the Matrigel implants was significantly inhibited, and the histological analysis confirmed a decrease of CD31(+) endothelial cells and of structures organized in cord and erythrocyte-containing vessels. In vitro, the compound inhibited dose-dependently the migration and the extracellular matrix-invasiveness of HUVEC and their capacity to form capillary like structures in Matrigel. 17-DMAG treatment also inhibited FGF-2 and VEGF-induced HUVEC proliferation and resulted in apoptosis. Accordingly, the expression of Hsp90 direct client proteins (pAkt and c-Raf-1) or their downstream substrates including pERK was also affected. 17-DMAG consistently increased the expression of Hsp70. Throughout the study similar results were obtained with 17-allylamino-17-demethoxygeldanamycin (17-AAG; NSC330507), the analog compound currently undergoing clinical trials. CONCLUSIONS: We show that the Hsp90 targeting agents 17-DMAG and 17-AAG inhibit angiogenesis. The strong effects on endothelial cell functions, in vitro, indicate that the antiangiogenic activity of 17-DMAG/17-AAG could also be due to a direct effect on endothelial cells. The oral bioavailability of 17-DMAG might be of advantage in investigating the potential of this compound in clinical trials with antiangiogenic as well as antiproliferative endpoints. 相似文献
65.
Marilyn A Roubidoux Judith Salmon Kaur Kent A Griffith Barbara Stillwater Paul Novotny Jeff Sloan 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1081-1086
The purpose is to determine breast cancer risk factors and correlates of mammographic parenchymal patterns among Alaska Native women. A retrospective review was performed of mammograms and mammogram records among 528 sequential screening mammogram examinations performed in Anchorage, Alaska. Mammogram density was classified by American College of Radiology (Breast Imaging Reporting and Data System) density patterns 1-4 (fat-->dense) and by percent density. Clinical data, including risk factors, ethnic group (Indian, Aleut, or Eskimo), and smoking status were obtained. Results were analyzed by univariate and multivariate analyses. Of 528 women, 164 were Indian, 155 were Aleut, and 209 were Eskimo. Mean age at first birth was lower and parity higher compared with published data in white women. Breast cancer risk factors were similar across ethnic groups. In multivariate analysis, patient age, parity, hormone replacement therapy, hysterectomy, and history of biopsy were associated, and smoking was not associated with density scores. Aleut and Indian women were less likely to have high-density mammograms than were Eskimo women (P = 0.0448). No significant differences were found between ethnic group for conventional breast cancer risk factors. Mammogram density was associated with age at screening, parity, hormone replacement therapy, hysterectomy, history of biopsy, and ethnicity but not smoking status. Eskimo women had higher mammogram density than Aleuts or Indians. 相似文献
66.
Burch PA Richardson RL Cha SS Sargent DJ Pitot HC Kaur JS Camoriano JK 《The Journal of urology》2000,164(5):1538-1542
PURPOSE: We examined the role of paclitaxel and cisplatin as first line therapy for metastatic urothelial cancer. MATERIALS AND METHODS: A total of 34 patients were enrolled in this study, and all were eligible for treatment and assessable for response. Patients received 135 mg./m.2 paclitaxel intravenously for 3 hours followed by 70 mg./m.2 cisplatin for 2 hours every 3 weeks to a maximum of 6 cycles. RESULTS: Of the patients 70% experienced a major response to treatment, which was partial/regression in 38% and complete in 32%. Toxicity was manageable with no episodes of grade 4 leukopenia or thrombocytopenia. Nonhematological toxicities included primarily nausea, anorexia and neuropathy, which rarely were severe. CONCLUSIONS: This regimen of paclitaxel and cisplatin is effective, safe and convenient to administer in an outpatient setting for advanced urothelial cancer. 相似文献
67.
N Chandhiok B S Dhillon S Datey A Mathur N C Saxena 《International journal of gynaecology and obstetrics》2006,92(2):170-175
OBJECTIVE: To study whether paramedical workers from rural primary health centers in India are able to administer oral misoprostol and actively manage the third stage of labor to prevent postpartum hemorrhage (PPH). METHOD: Cluster randomization was used to enroll 1200 women at 30 peripheral health centers from 5 states in India, 600 forming the study's intervention group (active management of the third stage of labor with 600 mug of oral misoprostol) and 600 forming the comparison group (in which the current government guidelines for the prevention of PPH were followed). The primary outcome was blood loss after delivery, which was measured using a calibrated blood collection drape. RESULTS: Age, literacy level, occupation, and gravidity were similar in the 2 groups. More than 70% of women in both groups had moderate anemia (hemoglobin level <10 g/dL). Paramedical workers followed instructions in almost all deliveries in the intervention group (99%). There was a significant reduction in duration of the third stage of labor (7.9 +/- 4.2 min vs. 10.9 +/- 4.3 min; p < .001) and median blood loss after delivery (100 mL vs. 200 mL; p < .001) in the intervention group. Overall, a low incidence of PPH was observed (<1%) in both groups. A greater number of women had moderate to severe shivering (12.7% vs. 0.5%) and a temperature higher than 38 degrees C (9.7% vs. 4.3%) in the intervention group, which was statistically significant. CONCLUSION: Simple interventions can be easily implemented in rural health care settings to reduce the blood loss during labor. This finding has significant implications for developing countries, in which the prevalence of anemia is high. 相似文献
68.
Objectives: The present study was designed to evaluate the efficacy of Lactuca sativa (LS) Linn. (Asteraceae) against scopolamine-induced amnesia and to validate its traditional claim as memory enhancer.Methods: Ethanol extract of fresh LS leaves (LSEE), standardized on the basis of quercetin content, was successively partitioned using various solvents viz., hexane, ethyl acetate, and n-butanol in increasing order of polarity. LSEE (50, 100, and 200?mg/kg) and its various fractions (at a dose equivalent to dose of LSEE exhibiting maximum activity), administered orally for 14 days, were evaluated for their memory enhancing effect against scopolamine-induced (1?mg/kg, i.p.) amnesia in 3–4 months old male Laca mice (n?=?6 in each group). The memory enhancing effect was evaluated using behavioural (elevated plus maze, novel object recognition and Morris water maze tests) and biochemical parameters (acetylcholinesterase activity, malonaldehyde, superoxide dismutase, nitrite, catalase, and reduced gultathione content). The results of the test substances were compared with both scopolamine and donepezil that was used as a standard memory enhancer and acetylcholinesterase inhibitor.Results: Scopolamine elicit marked deterioration of memory and alteration in biochemical parameters in comparison to the control group. LSEE and its n-butanol and aqueous fractions significantly (P?0.05) attenuated the scopolamine-induced amnesia that was evident in all the behavioural and biochemical test parameters. LSEE (200?mg/kg) and n-butanol fraction (15?mg/kg) exhibited maximum anti-amnesic effect among various tested dose levels.Discussion: The results exhibited that LS prophylaxis attenuated scopolamine-induced memory impairment through its acetylcholinesterase inhibitory and antioxidant activity validating its traditional claim. 相似文献
69.
Joseph N. Stember Jane P. Ko David P. Naidich Manmeen Kaur Henry Rusinek 《Journal of digital imaging》2013,26(2):239-247
Surface morphology is an important indicator of malignant potential for solid-type lung nodules detected at CT, but is difficult to assess subjectively. Automated methods for morphology assessment have previously been described using a common measure of nodule shape, representative of the broad class of existing methods, termed area-to-perimeter-length ratio (APR). APR is static and thus highly susceptible to alterations by random noise and artifacts in image acquisition. We introduce and analyze the self-overlap (SO) method as a dynamic automated morphology detection scheme. SO measures the degree of change of nodule masks upon Gaussian blurring. We hypothesized that this new metric would afford equally high accuracy and superior precision than APR. Application of the two methods to a set of 119 patient lung nodules and a set of simulation nodules showed our approach to be slightly more accurate and on the order of ten times as precise, respectively. The dynamic quality of this new automated metric renders it less sensitive to image noise and artifacts than APR, and as such, SO is a potentially useful measure of cancer risk for solid-type lung nodules detected on CT. 相似文献
70.
Various antiprotozoal drugs have been used to counteract the spread of giardiasis. However, due to increase in resistance to these compounds, there is an urgent need to find a natural biocompatible product to fight the pathogen in more healthy and effective way. The present study was designed to compare the therapeutic effect of probiotic Lactobacillus casei alone and in conjunction with antiprotozoal drugs on the outcome of giardiasis in murine model. BALB/c mice were challenged with Giardia intestinalis trophozoites, and 1 day after infection, these mice were treated with either probiotic alone or in conjunction with antiprotozoal drugs. Cyst, trophozoite, and lactobacilli counts were monitored vis-a-vis histopathological alterations in the small intestine. It was found that albendazole administered orally 1 day after Giardia infection was the most effective antiprotozoal drug among albendazole, tinidazole, metronidazole, and nitazoxanide. It reduced both the severity and duration of giardiasis. More specifically, oral administration of the probiotic L. casei in conjunction with albendazole further reduced the Giardia infection as was evident by the restored normal gut morphology. This suggests that probiotics and antiprotozoal drugs in combination may be the better alternative therapy for treatment of gastrointestinal diseases and enhanced recovery. 相似文献