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991.
Central neural distribution of immunoreactive Fos and CRH in relation to plasma ACTH and corticosterone during sepsis in the rat 总被引:1,自引:0,他引:1
Although brain pathways activated by sepsis may respond acutely to endotoxin administration, the long-term central response to sepsis is not known. We prepared male rats for hormonal sampling at the circadian nadir (AM) and peak (PM) after cecal ligation and puncture (CLP) or sham surgery. Diurnal variation of corticosterone was present on postoperative day (D) 3 and D4 after sham surgery but not after CLP. CLP increased Fos immunostaining in the nucleus of tractus solitarius (NTS), ventrolateral medulla, medullary raphe, parabrachial nucleus, hypothalamus, amygdala, bed nucleus of stria terminalis, and preoptic region. Fos responses were generally greatest on D1 but persisted to the AM of D4. The number of Fos-positive cell nuclei in the NTS on D3 and D4 did not differ but had greater variance on D3 than on D4 (P<0.01) with a divergent response in the PM of D3 that was correlated with plasma ACTH (r=0.927, P<0.01) but not with corticosterone. CLP increased CRH-staining intensity in the hypothalamic paraventricular neurons uniformly from D1 through D4 (P<0.01). Similar to Fos in NTS, this response was correlated with plasma ACTH (r=0.738, P<0.05) and adrenal size (r=0.730, P<0.05) in the PM of D3. Neuronal CRH became detectable after CLP in specific medullary areas on D1 and in the preoptic region on D3 and D4. Thus, the suppression of circadian variation by CLP was associated with central neural responses that increased in relation to plasma ACTH without apparent influence on the release of corticosterone. 相似文献
992.
Borderline personality disorder (BPD) is hallmarked by interpersonal problems. Conflicts with family members are no exception. METHODS: The NEO-Personality Inventory was administered to 25 pairs of patients and their family members. Both completed the questionnaire twice, responding about their own personality traits and responding about personality traits of the other. RESULTS: Patients and family members agreed on all five of the patient's personality traits. However, patients perceived the family members as being more neurotic, less extraverted and less open than the family members perceived themselves. CONCLUSIONS: Discrepant perceptions of personality traits 'may' create different relationship expectations and thus contribute to and intensify interpersonal difficulties. 相似文献
993.
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995.
An attenuated Plasmodium falciparum sporozoite (PfSPZ) vaccine is under development, in part, based on studies in mice with P. berghei. We used P. berghei and P. yoelii to study vaccine-induced protection against challenge with a species of parasite different from the immunizing parasite in BALB/c mice. One-hundred percent of mice were protected against homologous challenge. Seventy-nine percent immunized with attenuated P. berghei sporozoite (PbSPZ) (six experiments) were protected against challenge with P. yoelii sporozoite (PySPZ), and 63% immunized with attenuated PySPZ (three experiments) were protected against challenge with PbSPZ. Antibodies in sera of immunized mice only recognized homologous sporozoites and could not have mediated protection against heterologous challenge. Immunization with attenuated PySPZ or PbSPZ induced CD8+ T cell-dependent protection against heterologous challenge. Immunization with attenuated PySPZ induced CD8+ T cell-dependent protection against homologous challenge. However, homologous protection induced by attenuated PbSPZ was not dependent on CD8+ or CD4+ T cells, and depletion of both populations only reduced protection by 36%. Immunization of C57BL/10 mice with PbSPZ induced CD8+ T cell-dependent protection against P. berghei, but no protection against P. yoelii. The cross-protection data in BALB/c mice support testing a human vaccine based on attenuated PfSPZ for its efficacy against P. vivax. 相似文献
996.
Alcohol dehydrogenase genetic polymorphisms, low-to-moderate alcohol consumption, and risk of breast cancer 总被引:2,自引:0,他引:2
Visvanathan K Crum RM Strickland PT You X Ruczinski I Berndt SI Alberg AJ Hoffman SC Comstock GW Bell DA Helzlsouer KJ 《Alcoholism, clinical and experimental research》2007,31(3):467-476
BACKGROUND: In vitro, human isoenzymes encoded by genes homozygous for the ADH1C*1 or ADH1B*2 alleles metabolize ethanol to acetaldehyde at a faster rate than those homozygous for the ADH1C*2 or ADH1B*1 allele. Because alcohol is a known risk factor for breast cancer, we evaluated the joint association of genetic variants in ADH and alcohol consumption in relation to breast cancer. METHODS: A nested case-control study of 321 cases and matched controls was conducted. Five single nucleotide polymorphisms (SNPs) in the ADH1C and ADH1B genes were genotyped. Logistic regression was used to assess odds ratios (ORs) and 95% confidence limits (CIs) for each SNP. Haplotype analysis of all 5 SNPs was also undertaken. RESULTS: Among drinkers, the median intake of total alcohol was 13 g/wk (10th-90th percentiles; 4.5-135.9) in cases and 18 g/wk (10th-90th percentiles; 4.5-104.1) in controls. Women who drank alcohol tended to be at an increased risk of developing breast cancer compared with those who did not drink (OR=1.40%, 95% CI 0.97-2.03), particularly those who were premenopausal at the time of breast cancer diagnosis (OR=2.69%, 95% CI: 1.00-7.26). Of the known functional alleles, breast cancer risk was not significantly increased among carriers of at least 1 ADH1C*1 or ADH1B*2 allele, when compared with those homozygous for the genotype at each locus. However, breast cancer risk tended to be lower among women who inherited the G allele at ADH1B IVS1+896A>G (OR=0.62, 95% CI 0.37-1.04). Overall haplotype frequencies were not significantly different between cases and controls. CONCLUSIONS: In this study low levels of alcohol are associated with a modest increase in breast cancer risk that is not altered by known functional allelic variants of the ADH1B and 1C gene. The protective association conferred by the G allele at ADH1B IVS1+896A>G needs further evaluation. 相似文献
997.
In-coordinate mitral annulus movement might participate in the pathogenesis of functional mitral regurgitation. We evaluated a relationship between indices of mitral annulus systolic asynchrony and mitral regurgitation in patients after myocardial infarction in order to determine independent determinants of effective regurgitant orifice (ERO) area in a multivariate regression model.Tissue Doppler echocardiographic studies and quantitative analysis of mitral regurgitation were performed in 40 patients (33 men, 7 women, mean age 60.1 +/- 9.2 years) with a history of Q-wave myocardial infarction, with and without significant functional mitral regurgitation.A multivariate regression model showed that mitral annulus movement asynchrony index-difference between the longest and the shortest time from the R wave in the electrocardiogram to the cessation of systolic movement of the four aspects of mitral annulus, is an independent from ejection fraction, sphericity index, tenting, annulus diameter and infarct location, determinant of mitral regurgitation ERO area (r(2) change 0.72, p 相似文献
998.
A phase I clinical trial with monoclonal antibody ch806 targeting transitional state and mutant epidermal growth factor receptors 总被引:1,自引:0,他引:1
Scott AM Lee FT Tebbutt N Herbertson R Gill SS Liu Z Skrinos E Murone C Saunder TH Chappell B Papenfuss AT Poon AM Hopkins W Smyth FE MacGregor D Cher LM Jungbluth AA Ritter G Brechbiel MW Murphy R Burgess AW Hoffman EW Johns TG Old LJ 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(10):4071-4076
An array of cell-surface antigens expressed by human cancers have been identified as targets for antibody-based therapies. The great majority of these antibodies do not have specificity for cancer but recognize antigens expressed on a range of normal cell types (differentiation antigens). Over the past two decades, our group has analyzed thousands of mouse monoclonal antibodies for cancer specificity and identified a battery of antibodies with limited representation on normal human cells. The most tumor-specific of these antibodies is 806, an antibody that detects a unique epitope on the epidermal growth factor receptor (EGFR) that is exposed only on overexpressed, mutant, or ligand-activated forms of the receptor in cancer. In vitro immunohistochemical specificity analysis shows little or no detectable 806 reactivity with normal tissues, even those with high levels of wild-type (wt)EGFR expression. Preclinical studies have demonstrated that 806 specifically targets a subset of EGFR expressed on tumor cells, and has significant anti-tumor effects on human tumor xenografts, primarily through abrogation of signaling pathways. The present clinical study was designed to examine the in vivo specificity of a chimeric form of mAb 806 (ch806) in a tumor targeting/biodistribution/pharmacokinetic analysis in patients with diverse tumor types. ch806 showed excellent targeting of tumor sites in all patients, no evidence of normal tissue uptake, and no significant toxicity. These in vitro and in vivo characteristics of ch806 distinguish it from all other antibodies targeting EGFR. 相似文献
999.
Sebastian JK Mahr AD Ahmed SS Stone JH Romay-Penabad Z Davis JC Hoffman GS McCune WJ St Clair EW Specks U Spiera R Pierangeli S Merkel PA 《The Journal of rheumatology》2007,34(5):1027-1031
OBJECTIVE: Previous studies in small cohorts of patients with Wegener's granulomatosis (WG) or antineutrophil cytoplasmic antibody (ANCA) associated vasculitis have yielded conflicting data regarding the prevalence of antiendothelial cell antibodies (AECA), ranging from 8% to 100%, and the use of AECA as a measure of disease activity. We examined a large, well-characterized cohort of patients with WG and active disease for the presence of AECA. METHODS: Serum from subjects with WG who participated in a clinical therapeutic trial was collected at baseline, when all subjects had active disease. Clinical manifestations and disease activity were documented using the Birmingham Vasculitis Activity Score for WG (BVAS/WG). Serum AECA (IgG) was measured by cyto-ELISA using unfixed human umbilical vein endothelial cells (HUVEC). The AECA positivity cutoff was determined using 71 healthy control samples. Statistical analyses utilized Student's t test, chi-square and Fisher's exact tests, and linear regression. RESULTS: AECA were detected in 34 of 173 (20%) evaluated serum samples. Mean BVAS/WG did not differ between patients with (7.3 +/- 3.2) or without AECA (7.0 +/- 3.3) (p = 0.58). Among the 34 patients positive for AECA, the antibody titer did not correlate with disease activity (BVAS/WG; r = 0.09, p = 0.60). There were no statistically significant differences in the frequency of major clinical manifestations between patients with or without AECA. CONCLUSION: AECA, as measured using HUVEC, are not highly prevalent among patients with active WG, are not associated with specific clinical manifestations, and do not correlate with level of disease activity. 相似文献
1000.
Focal organizing pneumonia on surgical lung biopsy: causes, clinicoradiologic features, and outcomes
BACKGROUND: Organizing pneumonia (OP) is a histologic pattern that is morphologically distinctive but nonspecific and can be seen in diverse clinical settings. Focal OP has been described as a discrete form of OP, but relatively little is known regarding this clinicopathologic entity. METHODS: We sought to clarify the clinicoradiologic presentation, underlying causes, and outcomes associated with focal OP by retrospectively reviewing 26 consecutive cases diagnosed by surgical lung biopsy over an 8-year period from January 1, 1997, to December 31, 2004. RESULTS: All patients presented with an unifocal opacity detected on chest radiography (20 patients) or CT scans (6 patients). At the time of presentation, 10 patients (38%) had symptoms, including cough, shortness of breath, or chest pain; 16 patients were asymptomatic. Contrast-enhancement CT scanning or positron emission tomography (PET) scan was performed in 11 patients, and the results were positive in all. Surgical procedures included wedge resection in 21 patients (81%), segmentectomy in 3 patients (11%), and lobectomy in 2 patients (8%). Three case of focal OP (12%) were related to infections, but the remaining cases were cryptogenic. Follow-up over a median interval of 11 months (range, 1 to 71 months) yielded no recurrence of OP. CONCLUSIONS: The radiologic features of focal OP are often indistinguishable from those of lung cancer, and include positivity on contrast-enhancement CT scan and PET scan. Most cases of focal OP are cryptogenic, and infection is identified in a minority of cases. Surgical resection alone appears to suffice in the management of cryptogenic focal OP. 相似文献