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排序方式: 共有3133条查询结果,搜索用时 15 毫秒
1.
Malignant glioma is the most common intracranial tumor with a dismal prognosis. The radiosensitizing effect of silver nanoparticles (AgNPs) on glioma both in vitro and in vivo had been demonstrated in the previous studies of our group. However, the underlying mechanism is still unclear. Consistent with previous studies, a size and dose dependent antitumor effect and significant radiosensitivity enhancing effect of AgNPs were observed in our experiment system. We also found that cell protective autophagy could be induced by AgNPs and/or radiation, which was verified by the use of 3-MA. The mechanism through which had autophagy and the enhancement of radiosensitivity taken place was further investigated with inhibitors of ERK and JNK pathways. We demonstrated that ERK and JNK played pivotal roles in the radiosensitivity enhancement. Inhibiting ERK and JNK with U0126 and SP600125 respectively, we found that the autophagy level of the cells treated with AgNPs and radiation were attenuated. Moreover, SP600125 down-regulated the apoptosis rate of the co-treated cells significantly. Taken together, the present study would have important impact on biomedical applications of AgNPs and clinical treatment for glioma.  相似文献   
2.
Transplanting the Highly Sensitized Patient: The Emory Algorithm   总被引:4,自引:0,他引:4  
Renal transplant patients sensitized to HLA antigens comprise nearly one-third of the UNOS wait-list and receive 14% of deceased donor (DD) transplants, a rate half that of unsensitized patients. Between 1999 and 2003, we performed 492 adult renal transplants from DD; 120 patients (approximately 25%) had a panel reactive antibody (PRA) of >30%, with nearly half (n = 58) having a PRA of >80%. Our approach is based upon high-resolution solid-phase HLA antibody analysis to identify class I/II antibodies and a 'virtual crossmatch' to predict compatible donor/recipient combinations. Recipients are excluded from the United Network for Organ Sharing match run if donors possess unacceptable antigens. Thus, when sensitized patients appear on the match run, they have a high probability of a negative final crossmatch. Here, we describe our 5-year experience with this approach. Five-year graft survival ranged from 66% to 70% among unsensitized (n = 272), moderately sensitized (PRA < 30%, n = 100) and highly sensitized (>30% PRA; n = 120) patients, equal to the average national graft survival (65.7%). The application of this approach (the Emory Algorithm) provides a logical and systematic approach to improve the access of sensitized patients to DD organs and promote more equitable allocation to a highly disadvantaged group of patients awaiting renal transplantation.  相似文献   
3.
Implantation of left ventricular assist devices (LVAD) is associated with HLA antibody sensitization. The objective of this study was to determine the specificity of antibodies produced by LVAD recipients using a combination of ELISA, Luminex and microcytotoxicity assays. Fifty-one LVAD patients were studied, from 44 to 838 days post-implantation. No patient developed HLA antibodies, although 24 produced IgG antibodies detectable in both ELISA and Luminex assays. These antibodies manifest as positive reactions with class I and class II wells of the ELISA and also blank wells. In Luminex assays, they produce high MFI readings with the negative control beads. Antibodies were detected 18 to 228 days after implantation. This reactivity was found to be directed against bovine serum albumin (BSA), commonly used to block non-specific binding in ELISA and Luminex assays; absorption of sera with BSA-coated beads completely abrogated reactivity in all solid phase assays, but did not eliminate anti-HLA antibodies in control sera. Ten of the 24 patients have proceeded to transplantation, with a 1-year graft survival of 69%. In conclusion, it appears that implantation of LVADS disrupts immunoregulatory pathways leading to production of anti-albumin antibodies. These can be misinterpreted as anti-HLA antibodies in solid phase assays.  相似文献   
4.
Summary Dock workers (n = 218) occupationally exposed to green coffee beans (GCB) were studied, using a specific questionnaire for allergic symptoms and skin tests for common and occupational allergens. Thirty-one workers (14.3%) complained of allergic symptoms of the eye, nose and bronchial system at the workplace. The prick tests, using both commercial allergens and specific extracts prepared from the most common types of coffee and their corresponding sacks, confirmed a sensitization in 21 workers (9.6%). A positive skin reaction to castor beans (CB) was found in nearly all these cases; in ten workers there was also a positive reaction to GCB allergens and in 14 cases prick tests were positive to extracts of sacks. There was a good concordance between prick tests and specific IgE for CB (95.0%) and also, but to a lesser extent, for GCB. The authors concluded that there is a significant risk of sensitization to CB and GCB allergens in dock workers occupied in handling green coffee bean, despite the fact that the exposure is not continuous. CB emerged as a common contaminant of GCB from various countries. For effective prevention, a modification of the methods of transport is required to avoid CB contamination to other products. Eliminating environmental dust during shipping operations is the most important preventive measure and it can be achieved by the use of containers, as some exporting countries are already doing.  相似文献   
5.
BACKGROUND: The role of atopy in the evolution to chronic obstructive disease remains controversial. AIM: We aimed to assess the association between individual sensitization to common allergens and lung function. METHOD: We analysed data from 12,687 subjects aged 20 to 44 years, from 34 centres in 15 countries participating in the European Community Respiratory Health Survey (ECRHS). Participants performed a blood test, lung function test, methacholine challenge, and answered an administered questionnaire. The relationships between specific IgE, FEV1 and FEV1/FVC ratio were assessed for each study centre stratified by sex, followed by random effects meta-analysis. RESULTS: Asthmatics sensitized to house dust mite had a lower FEV1 (-119 mL in women and -112 mL in men) and FEV1/FVC ratio (-1.95%, and -2.48%) than asthmatics without sensitization. Asthmatics sensitized to cat had a lower FEV1 (statistically significant for women only) and a lower FEV1/FVC ratio. Asthmatic women sensitized to grass had a lower FEV1 and a lower ratio, and those sensitized to Cladosporium had a lower FEV1. A weak association was found with sensitization to cat and to Cladosporium among non-asthmatic women, which disappeared after adjusting for BHR. CONCLUSION: We conclude that atopy was related to a lower lung function, which was only apparent among asthmatics. This relationship was explained by specific sensitization to cat and to house dust mite, the latter being homogeneous across areas.  相似文献   
6.
Central Sensitization Theory of Migraine: Clinical Implications   总被引:4,自引:2,他引:2  
David Dodick  MD  ; Stephen Silberstein  MD 《Headache》2006,46(S4):S182-S191
The clinical science of migraine headache continues to evolve. Theories of the pathophysiology of migraine have progressed from the early vascular basis of migraine to more complex current theories that emphasize the centrality of neuronal dysfunction. The most recently articulated theory of migraine is the central sensitization hypothesis, which proposes that altered processing of sensory input in the brainstem, principally the trigeminal nucleus caudalis, could account for many of the temporal and symptomatic features of migraine, as well as its poor response to triptan therapy when such treatment is initiated hours after the onset of pain. Both preclinical and clinical data support the central sensitization theory. A critical clinical implication of this theory is that drugs that are capable of either aborting or arresting the process of central sensitization, most prominently dihydroergotamine, may have a unique role in the treatment of migraine. An additional, and highly practical, implication is based upon the finding that cutaneous allodynia—pain arising from innocuous stimulation of the skin, as in hair brushing or the application of cosmetics—is an easily identifiable marker of central sensitization. Thus, the presence or absence of cutaneous allodynia can be integrated into the routine clinical assessment of migraine and utilized as a determinant of treatment. Future basic and clinical research on central sensitization is likely to be of ongoing importance to the field.  相似文献   
7.
 We examined the effect of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX), an antagonist of the α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) subtype of glutamate receptor, on the development and expression of behavioral sensitization to amphetamine and cocaine in rats. A single injection of NBQX (12.5 mg/kg) administered 30 min prior to cocaine during the induction phase (days 1–5) prevented the development of cocaine sensitization, assessed by responsiveness to cocaine challenge on day 8. This NBQX regimen did not affect development of amphetamine sensitization. Two pretreatment injections of NBQX, one 20 min before and one 70 min after amphetamine on each day of the induction phase (days 1–6), did not affect sensitization of stereotypy but prevented sensitization of post-stereotypy ambulatory hyperactivity (both assessed by responsiveness to amphetamine challenge on day 8). The effect of NBQX on ambulatory sensitization was dose-dependent (attenuation with 12.5 mg/kg, complete prevention with 25 mg/kg). In contrast to its effects on development, NBQX (25 mg/kg) did not prevent expression of sensitization to cocaine or amphetamine. NBQX itself exerted no significant effects on locomotor activity in either drug-naive rats or rats that had received either NBQX or amphetamine repeatedly. These findings support a requirement for AMPA receptor stimulation in the development of locomotor sensitization to cocaine and amphetamine, but suggest a different mechanism for sensitization of amphetamine stereotypy. Received: 14 January 1997 / Final version: 24 June 1997  相似文献   
8.
The optimal conditions for inactivation of Bordetella pertussis organisms with glutaraldehyde for the production of a safe and potent whole cell pertussis vaccine were investigated. Two bacterial harvests from B. pertussis strain 10536 were treated with glutaraldehyde, each with 0.025, 0.05 and 0.1% concentrations of glutaraldehyde for 10, 60 and 120 min. The nine types of glutaraldehyde-inactivated pertussis vaccine (GIPV) and conventional heat-inactivated pertussis vaccine (HIPV) preparations made from two bacterial harvests were comparatively evaluated for the mouse weight gain test (MWGT), potency, and the histamine-sensitization (HS) and leucocytosis-promoting-factor (LPF) tests. The minimum period for killing the B. pertussis organisms with glutaraldehyde was>10 min for 0.025%, 10 min for 0.05% and 5 min for 0.1% concentration. The average loss in opacity varied from 5 to 10% for GIPV preparations and was 14% for HIPV preparations. The GIPV preparations except those inactivated with 0.025% glutaraldehyde for 10 min (GIPV-A) were much less toxic than the HIPV preparations in the MWGT. The GIPV-A preparations did not pass the MWGT. The GIPV preparations were also much less toxic in HS and LPF tests than the HIPV preparation. The potency of GIPV preparations inactivated with 0.05% glutaraldehyde for 10 min (GIPV-D) was similar to that of HIPV preparations. The prolonged treatments with glutaraldehyde reduced the potency. The GIPV-D preparation with good potency and less toxicity was found to be inactivated with glutaraldehyde under optimal conditions. All the preparations were innocuous in the abnormal toxicity test.  相似文献   
9.
The ontogeny of the behavioral effects of acute cocaine administration and behavioral sensitization to cocaine in rat pups was investigated. Acute behavior stimulating effects of cocaine were observed in pups as young as 7 postnatal days (PND) old, although they needed a higher dose of cocaine than adult rats to evoke the same motor effects. An adult dose-response curve pattern of stereotypy and locomotion to acute cocaine treatment was observed at PND 21, and of rearing at PND 28. Rats aged PND 7, 14, 21, 28, and 56 received repeated injections of saline or cocaine (15 mg/kg) twice a day for 5 consecutive days. After a 3-week period of abstinence, sensitization to a challenge dose of cocaine was assessed. Cocaine-induced stereotyped behavior was enhanced significantly only in rats in which cocaine pretreatment was initiated on PND 21, 28, and 56, but not earlier on PND 7 and 14. Adult female rats given repeated cocaine injections on PND 56–60 showed significantly greater sensitization than males, but no such sex difference was observed in pups given cocaine repeatedly on PND 21–25 or 28–32. These results show clearly that cocaine-induced behavioral sensitization in rats occurred only when subchronic cocaine administration was commenced on PND 21 or later.  相似文献   
10.
As natural rubber latex (latex) has become more widespread in our environment, physicians have become increasingly aware of the problem of possible allergic reactions. Many fatal and near-fatal incidents have been reported (mainly during surgery) (1—3) and data has been published on groups frequently exposed to latex, such as patients with spina bifida (4—9), healthcare professionals (10—12) and occupationally exposed persons (13). The incidence of latex allergy in children seems to be increasing (14). Tests are therefore needed which can reliably detect sensitization to latex. Our aim was to compare the diagnostic accuracy of three commercial immunoassays for measuring specific IgE in serum to latex.  相似文献   
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