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51.
Jia C  Halpern M 《Brain research》2003,977(2):261-269
The vomeronasal system is a nasal chemosensory system involved in pheromone detection. The chemosensory receptor neurons are located in the sensory epithelium of the vomeronasal organ (VNO). Their axons terminate in the glomeruli of the accessory olfactory bulb (AOB). In this study, we examined the expression of calbindin D28k (CB) in the rat VNO and AOB. In the VNO, a subpopulation of receptor neurons in the middle layer of the sensory epithelium was immunostained with antibodies to CB. Their axons could be traced to terminate in a group of glomeruli in the anterior half of the AOB glomerular layer. This group of CB-immunostained glomeruli in the anterior half of the AOB included a few large glomeruli close to the boundary between the anterior and posterior halves of the AOB, and several small glomeruli scattered in the anterior region of the AOB glomerular layer. The positions of the CB-immunostained glomeruli in the AOB, especially those close to the anterior-posterior boundary, were similar in the two bulbs and in different rats. No sex difference was found. A developmental study showed that the CB-immunoreactive receptor neurons in the middle layer of the VNO sensory epithelium and CB-immunoreactive glomeruli in the anterior AOB were present on the 14th postnatal day and older. The distribution pattern of the CB-immunostained receptor neurons and their localized projection suggest the possibility that these neurons may express the same or functionally related pheromone receptor genes.  相似文献   
52.
OBJECTIVE: Lipopolysaccharide pretreatment is known to reduce myocardial infarct size, but the mechanism has not been elucidated. We hypothesized that heat shock protein 70, induced by lipopolysaccharide pretreatment, formed complexes with inhibitory kappaBalpha, thereby inhibiting degradation and attenuating activation of nuclear factor kappaB and cellular injury in rat myocardium. METHODS: Fifteen Sprague-Dawley rats were given saline solution (control group) or lipopolysaccharide. After 48 hours, 5 hearts in each group were excised without ischemia for examination of heat shock protein 70 and inhibitory kappaBalpha levels and detection of heat shock protein 70-inhibitory kappaBalpha complexes. Myocardium from the remaining 10 rats in each group was exposed to 30 minutes of ischemia and 30 minutes of reperfusion (n = 5) to evaluate nuclear factor kappaB activity or to 24 hours of reperfusion (n = 5) to evaluate infarct size. RESULTS: Infarct size was reduced in the lipopolysaccharide group (P <.05). Nuclear factor kappaB was activated in the control ischemia group and attenuated in the lipopolysaccharide group (P <.05). Heat shock protein 70 levels were increased in the lipopolysaccharide group (P <.05), but inhibitory kappaBalpha levels were similar in both groups. Heat shock protein 70-inhibitory kappaBalpha complexes were detected only in the lipopolysaccharide group. Colocalization of the 2 proteins was observed in the lipopolysaccharide group. CONCLUSIONS: Heat shock protein 70, induced by lipopolysaccharide pretreatment, forms complexes with inhibitory kappaBalpha and attenuates activation of nuclear factor kappaB and myocardial infarct size. Our results suggest that attenuation of nuclear factor kappaB through a mechanism forming heat shock protein 70-inhibitory kappaBalpha complexes might protect the myocardium from ischemia-reperfusion injury.  相似文献   
53.
BACKGROUND: Insulin-like growth factor I (IGF-I) stimulates cell proliferation and inhibits apoptosis in the lung and other tissues by interacting with the IGF-I receptor. The major binding protein for IGF-I, insulin-like growth factor-binding protein 3 (IGFBP-3), modulates the effects of IGF-I but also inhibits cell growth and induces apoptosis independent of IGF-I and its receptor. In a prospective study of men in Shanghai, China, we examined the association between serum levels of IGF-I and IGFBP-3 and the subsequent risk of lung cancer. METHODS: From 1986 to 1989, serum was collected from 18,244 men aged 45-64 years living in Shanghai without a history of cancer. We analyzed IGF-I and IGFBP-3 levels in serum from 230 case patients who developed incident lung cancer during follow-up and from 740 control subjects. RESULTS: Among 230 case patients and 659 matched control subjects, increased IGF-I levels were not associated with increased risk of lung cancer. However, for subjects in the highest quartile relative to the lowest quartile of IGFBP-3, the odds ratio (OR) for lung cancer, adjusted for smoking and IGF-I, was 0.50 (95% confidence interval [CI] = 0.25 to 1.02). When the analysis was restricted to ever smokers (184 case patients and 344 matched control subjects), the OR for lung cancer in men in the highest quartile of IGFBP-3 relative to those in the lowest quartile, adjusted for smoking and IGF-I, was 0.41 (95% CI = 0.18 to 0.92). CONCLUSIONS: In this prospective study of Chinese men, higher serum levels of IGF-I did not increase the risk of lung cancer. However, subjects with higher serum levels of IGFBP-3 were at reduced risk of lung cancer. This finding is consistent with experimental data that indicate that IGFBP-3 can inhibit cellular proliferation and induce apoptosis independent of IGF-I and the IGF-I receptor.  相似文献   
54.
Sun CL  Yuan JM  Lee MJ  Yang CS  Gao YT  Ross RK  Yu MC 《Carcinogenesis》2002,23(9):1497-1503
Experimental studies have shown that tea and tea polyphenols have anticarcinogenic properties. There have been no prospective investigations examining the relationship between tea polyphenols and cancer risk using validated biomarkers. In the present study, a nested case-control study design was used to investigate the association between prediagnostic urinary tea polyphenol markers and subsequent risk of gastric and esophageal cancers. One hundred and ninety incident cases of gastric cancer and 42 cases of esophageal cancer occurring in members of the Shanghai Cohort (18 244 men aged 45-64 years at recruitment with up to 12 years of follow-up) were compared with 772 cohort control subjects. The control subjects were individually matched to the index cases by age, month and year of sample collection, and neighborhood of residence (case-control ratio = 1:3 for gastric cancer, 1:5 for esophageal cancer). Urinary tea polyphenols, including epigallocatechin (EGC) and epicatechin (EC), and their respective metabolites 5-(3',4',5'-trihydroxyphenyl)-gamma-valerolactone (M4) and 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone (M6), were measured in all study subjects by means of a validated assay. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from logistic regression models. After exclusion of cases diagnosed under 4 years follow-up, urinary EGC positivity showed a statistically significant inverse association with gastric cancer (OR = 0.52, 95% CI = 0.28-0.97) after adjustment for Helicobactor pylori seropositivity, smoking, alcohol drinking, and level of serum carotenes. The protective effect was primarily seen among subjects with low (below population median) serum carotenes. The odds ratio for EGC positivity was 0.49 (95% CI = 0.26-0.94) among subjects with low serum carotenes while the corresponding odds ratio among subjects with higher levels of serum carotenes was 1.02 (95% CI = 0.46-2.28). Similar tea polyphenol-cancer risk associations were observed when the gastric cancer and esophageal cancer sites were combined. The present study provides direct evidence that tea polyphenols may act as chemopreventive agents against gastric and esophageal cancer development.  相似文献   
55.
BACKGROUND: Numerous cultural and ethnic factors may directly and indirectly influence treatment outcome in schizophrenia. The present study compared the response to antipsychotic treatment in 3 ethnic groups of patients with schizophrenia. METHOD: Fifty black, 63 mixed descent, and 79 white patients with DSM-IV-diagnosed schizophrenia or schizophreniform disorder who were participants in multinational clinical drug trials were assessed by means of the Positive and Negative Syndrome Scale (PANSS). Treatment response was measured by the change in PANSS total scores and the change in positive, negative, and general psychopathology subscale scores from baseline to 6 weeks. Also, the percentage of responders (defined as > or = 40% reduction in PANSS total scores) was calculated for each group. RESULTS: Baseline PANSS scores differed significantly, being higher for black and mixed descent patients. Mixed descent patients showed the greatest mean +/- SD percentage reduction in PANSS total score (29.4 +/- 21.6) followed by black (28.4 +/- 14.7) and white (11.4 +/- 27.6) patients. Analysis of covariance revealed a significant effect of ethnicity on the reduction in PANSS total scores (p < .0001). The numbers of responders were 20 mixed descent (32%), 12 black (24%), and 7 white (9%) patients (p = .002). CONCLUSION: Significant ethnic differences in acute antipsychotic treatment response are demonstrated by this study. Factors such as diet, nutritional status, body mass, and substance use could be important, as well as genetically determined ethnospecific pharmacokinetic and pharmacodynamic differences. Delayed help-seeking may account for the higher baseline scores in the black and mixed descent patients.  相似文献   
56.
BACKGROUND: Twenty years have elapsed since the National Institute of Mental Health Collaborative Depression Study reported on the early course and treatment of major depression within the mental health sector. Using similar methods, an observational study was conducted to assess relationships between initial depression severity, personality dysfunction and other baseline characteristics, subsequent treatment, and 3-month outcomes among persons admitted to public and voluntary sector outpatient clinics, including 1 academic program. METHODS: A 2-stage sampling technique was used to recruit subjects (N = 165) diagnosed by the Structured Clinical Interview for DSM-IV, Patient Version, as having a major depression episode. Sociodemographic and clinical characteristics were assessed at admission. Data on treatment and outcome were obtained at 3 months using structured instruments from the Longitudinal Interview Follow-up Evaluation. Logistic regression was used to assess hypothesized predictors of early recovery. Analyses were carried out in the total sample and after dichotomizing subjects by baseline depression severity. RESULTS: Fifty (30.3%) of the 165 subjects met recovery criteria. Less than half of the subjects (45%) met criteria for adequate pharmacotherapy. Less severe depression, having received adequate antidepressant treatment, female sex, and being married independently predicted early recovery. In the more depressed subgroup, early recovery was associated with female sex. Among less severely depressed subjects, high personality dysfunction scores and being married were significant predictors. CONCLUSIONS: Initial depression severity and receiving adequate pharmacotherapy predict early recovery in individuals with major depression seeking outpatient treatment. A minority of persons receive intensive antidepressant treatment. Less severe personality dysfunction and being married predicts early recovery among persons with less severe depression.  相似文献   
57.
The middle vault is a transition zone between the nasal tip and nasal bones and plays an important role in profile, tip projection, tip rotation, and tip support. This report presents an alternative to conventional techniques specific to the middle nasal vault for a patient population with particular nasal features. A narrow middle vault with internal nasal valve collapse is functionally and aesthetically addressed by the insertion of spreader grafts. However, the inverse of this situation is sometimes encountered. A patient with a broad middle vault and without internal nasal valve collapse will benefit from reduction of the horizontal width of the cartilaginous dorsum, which is in effect the reverse of spreader grafts. This effect is achieved by excising a vertical wedge-shaped strip of cartilage that follows the length of the upper lateral cartilage at the junction of the upper lateral cartilage and the dorsal nasal septum.  相似文献   
58.
The study aimed to investigate whether self-reported dietary variables were associated with mammographic parenchymal patterns, which have been shown to predict risk of breast cancer. Among the 3,421 women, ages 45-74 years, common to two independent population-based cohorts, mammographic parenchymal patterns and current dietary habits were assessed for 406 randomly chosen participants. Logistic regression methods were used to compare dietary and other lifestyle profiles between subjects classified as displaying high (cases) and low risk (controls) parenchymal patterns. After adjustment for energy intake and other potential confounders, dietary soy protein intake was inversely related to risk of high-risk parenchymal pattern (odds ratio, 0.41; 95% confidence interval, 0.18-0.94, highest versus lowest quartile of intake). Similarly, the highest versus lowest quartile of dietary soy isoflavone intake was significantly related to low-risk parenchymal patterns (odds ratio, 0.44; 95% confidence interval, 0.20-0.98). The association between high soy intake and a reduced risk of mammographic parenchymal patterns that are associated with high breast cancer risk may have important implications in breast cancer prevention.  相似文献   
59.
The association between soyfood consumption and subsequent bladder cancer risk was investigated in a population-based cohort study, the Singapore Chinese Health Study. As of December 31, 2000, 329,848 person-years of follow-up were accrued. Sixty-one histologically confirmed incident bladder cancer cases were identified. Information on soyfood consumption at baseline was obtained through in-person interviews using a validated dietary questionnaire. Relative risks and 95% confidence intervals were calculated using the Cox proportional hazard regression method. High intake of soyfood was statistically significantly related to an elevated risk of bladder cancer. Relative to the lowest quartile of energy-adjusted total soy intake (<36.9 g/1000 Kcal), the highest quartile of total soy intake (> or =92.5 g/1000 Kcal) was associated with a 2.3-fold increase in bladder cancer risk (95% confidence interval = 1.1-5.1) after adjustment for cigarette smoking and level of education. Similar results were obtained for intakes of soy protein and soy isoflavones. The soyfood-bladder cancer risk association did not differ significantly between men and women and was not explained by other dietary factors. The soy-cancer relationship became stronger when the analysis was restricted to subjects with longer (> or =3 years) duration of follow-up. To our knowledge, this is the first epidemiological report on the effect of dietary soy on bladder cancer risk.  相似文献   
60.
Remarks are offered on the future of the HIV-infected individual, the system's ability to care for more HIV-infected individuals, and our global ability to maintain our efforts to fight this disease. © 1993 Wiley-Liss, Inc.  相似文献   
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