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71.
In infantile cystinosis the amino acid cystine preferentially accumulates in phagocytic cells, polymorphonuclear leucocytes (PMN) and monocytes, rather than in lymphocytes. We previously described functional abnormalities in the oxidative metabolism and locomotion of cystinotic PMN and monocytes. The present study shows an abnormal lymphocyte polyclonal activation as evidenced by a decreased immunoglobulin (Ig) production and generation of Ig-containing cells (ICC) in cultures of peripheral blood mononuclear cells (PBMC) from cystinotic children upon stimultion with pokeweed mitogen andStaphylococcus aureus Cowan I. However, monocyte depletion from cystinotic PBMC fully reconstituted Ig production and ICC generation, indicating: (1) the presence of an increased monocyte-dependent suppression on lymphocyte polyclonal activation, and (2) that the intrinsic ability of cystinotic lymphocytes to respond to polyclonal stimulation was preserved. The increased cystinotic monocytedependent suppressive effect was not mediated by prostaglandin E2 (PGE2) since its production by cystinotic PBMC upon polyclonal activation was not different from that of controls. In addition, the sensitivity of cystinotic lymphocytes to the immunosuppressive effect of varying concentrations of exogenous PGE2 was similar to that of controls. Finally, indomethacin and 2-mercaptoethanol, two agents able to scavenge hydroxyl (OH) radicals, restored Ig production by cystinotic PBMC, suggesting a role for reactive oxygen species in the increased cystinotic monocyte-dependent suppression.  相似文献   
72.
Neuronal apoptosis has been shown to occur in HIV infection by a number of in vivo and in vitro studies, however, the cause of neuronal damage in AIDS is still unclear and its relationships with the cognitive disorders characteristic of HIV dementia remain a matter of debate. In this review, based on our experience, we analyse the techniques used to identify neuronal apoptosis on post-mortem AIDS brains and describe the relationships of neuronal apoptosis with the stage of disease, a history of HIV-dementia, the degree of productive HIV infection, microglial activation, blood-brain barrier involvement and axonal damage. We conclude that the severity of neuronal apoptosis in the cerebral cortex correlates with the presence of cerebral atrophy, but not with the cognitive disorders. There is no global quantitative correlation between neuronal apoptosis and HIV encephalitis, microglial activation or axonal damage. However we found some topographical correlation between these changes. We conclude that neuronal apoptosis and consequent neuronal loss, in HIV infected patients, are probably not related to a single cause. It seems likely that microglial activation, directly or indirectly related to HIV infection of the CNS, plays a major role in its causation possibly through the mediation of oxidative stress. Axonal damage, either secondary to microglial activation, or to the intervention of systemic factors may also contribute to neuronal apoptosis.  相似文献   
73.
Assisted liposuction of lipomas   总被引:2,自引:0,他引:2  
Assisted liposuction of lipomas is the partial or sometimes complete aspiration of the subcutaneous benign lipomas followed by the blind resection of their membrane. This procedure limits the scar and the risk of recurrence. The author purposes here this technical note.  相似文献   
74.
Influence of sleep deprivation on neuroactive steroids in major depression.   总被引:5,自引:0,他引:5  
There is evidence from preclinical and clinical studies that concentrations of neuroactive steroids are altered in depression and normalize after antidepressant pharmacotherapy. However, no data are available concerning the impact of sleep deprivation on the concentrations of neuroactive steroids. A total of 29 drug-free patients (12 men, 17 women) suffering from major depression according to DSM-IV criteria were treated with partial sleep deprivation (PSD). Response to PSD was defined as a reduction of at least 30% according to the six-item version of the Hamilton depression scale (6-HAMD). Plasma samples were taken the day before and after PSD (days 0 and 1) and after one night of recovery sleep (day 2) at 8:00 am. The samples were quantified for neuroactive steroids by means of a highly sensitive and specific combined gas chromatography/mass spectrometry analysis. There was no influence of PSD on the concentrations of neuroactive steroids either in PSD responders (n=20) or in nonresponders (n=9). However, nonresponders showed significantly higher concentrations of 3alpha,5alpha-tetrahydroprogesterone (3alpha,5alpha-THP), 3alpha,5beta-tetrahydroprogesterone (3alpha,5beta-THP), and dehydroepiandrosterone (DHEA) before or after PSD compared to responders. In contrast to antidepressant drugs, which correct the dysequilibrium of neuroactive steroids in major depression within several weeks, PSD does not affect the concentrations of neuroactive steroids either in responders or in nonresponders.  相似文献   
75.
A toxicokinetic model is proposed to predict the time evolution of malathion and its metabolites, mono- and dicarboxylic acids (MCA, DCA) and phosphoric derivatives (dimethyl dithiophosphate [DMDTP], dimethyl thiophosphate [DMTP], and dimethyl phosphate [DMP]) in the human body and excreta, under a variety of exposure routes and scenarios. The biological determinants of the kinetics were established from published data on the in vivo time profiles of malathion and its metabolites in the blood and urine of human volunteers exposed by intravenous, oral, or dermal routes. In the model, body and excreta compartments were used to represent the time varying amounts of each of the following: malathion, MCA, DCA, DMDTP, DMTP, and DMP. The dynamic of intercompartment exchanges was described mathematically by a differential equation system that ensured conservation of mass at all times. The model parameters were determined by statistically adjusting the explicit solution of the differential equations to the experimental human data. Simulations provide a close approximation to kinetic data available in the published literature. When simulating a dermal exposure to malathion, the main route of entry for workers, the model predicts that it takes an average of 11.8 h to recover half of the absorbed dose of malathion eventually excreted in urine as metabolites, compared to 3.2 h following an intravenous injection and 4.0 h after oral administration. This shows that following a dermal exposure, the absorption rate governs the urinary excretion rate of malathion metabolites because the dermal absorption rate is much slower than biotransformation and renal clearance processes. The model served to establish biological reference values for malathion metabolites in urine since it allows links to be made between the absorbed dose of malathion and the time course of cumulative amounts of metabolites excreted in urine. From the no-observed-effect level (NOEL) of 0.61 micromol/kg/day derived from the data of Moeller and Rider (1962), the model predicts corresponding biological reference values for MCA, DCA, and phosphoric derivatives of 44, 13, and 62 nmol/kg, respectively, in 24-h urine samples. The latter were used to assess the health risk of workers exposed to malathion in botanical greenhouses, starting from urinary measurements of MCA and DCA metabolites.  相似文献   
76.
Cholecystokinin-tetrapeptide (CCK-4) induces panic attacks both in patients with panic disorder (PD) and healthy volunteers. It has been shown that panic elicited by CCK-4 is improved after treatment with antidepressants. Moreover, a reduction of CCK-4-induced panic has also been demonstrated after treatment with lorazepam in single subjects and after selective GABAergic treatment with vigabatrin. Although benzodiazepines are widely used as anxiolytics, no controlled study on the effects of benzodiazepines on CCK-4-induced panic symptoms is available so far. Therefore, we investigated the effects of alprazolam and placebo on CCK-4-induced panic symptoms in a double-blind, placebo-controlled study. A total of 30 healthy subjects were challenged with 50 microg CCK-4. Out of these 30 subjects, 26 showed a marked panic response to CCK-4. Subjects were rechallenged after a 7-day interval and treated with 1 mg alprazolam or placebo 1 h prior to the second CCK-4 challenge. Panic was assessed using the acute panic inventory (API) and a DSM-IV-derived panic symptom scale (PSS). Moreover, the number of reported symptoms and self-rated anxiety and arousal were recorded. We found a significant reduction of the API and PSS scores and of the number of reported symptoms compared to placebo. Moreover, compared to placebo the CCK-4-induced ACTH and cortisol release were significantly attenuated during the CCK-4 challenge after alprazolam treatment. However, also placebo treatment reduced CCK-4-induced anxiety and HPA-axis activation to a certain extent. In conclusion, our data show that alprazolam reduces CCK-4-induced panic, which supports the hypothesis of a possible interaction between the GABA and the CCK system.  相似文献   
77.
PURPOSE: The impact of consensus recommendations for systemic therapy on outcome of disease is unclear. We evaluated if compliance with guidelines for systemic adjuvant treatment is associated with improved survival of women with node-negative breast cancer. PATIENTS AND METHODS: The study population included women diagnosed with invasive node-negative breast cancer in Québec, Canada, in 1988 to 1989, 1991 to 1992, and 1993 to 1994. Information was collected by chart review, linkage with administrative databases, and queries to attending physicians. Guidelines from the 1992 St Gallen conference were used as standard of care. Survival was estimated by Kaplan-Meier and Cox proportional hazards analyses. RESULTS: Among 1,541 women, 358 died before December 1999. Median follow-up was 6.8 years. Seven-year event-free and overall survivals were 66% and 81%, respectively. Survival was 88%, 84%, and 74% in women at minimal, moderate, or high risk of recurrence. Virtually all women at minimal risk were treated according to the consensus (98.4% of 370). In comparison, adjusted hazard ratios of death were 1.0 (95% CI, 0.6 to 1.7) and 2.3 (95% CI, 1.3 to 4.0) among women at moderate risk treated according to the consensus or not, respectively. Among women at high risk, adjusted hazard ratios of death were 2.0 (95% CI, 1.4 to 2.8) and 2.7 (95% CI, 1.9 to 3.9), respectively. Both risk category (P <.0005) and compliance with guidelines (P <.0005) were independent significant predictors of survival. CONCLUSION: Treatment according to consensus recommendations is associated with improved survival of women with breast cancer in the community. Promoting the adoption of guidelines for treatment is an effective strategy for disease control.  相似文献   
78.
PURPOSE: This randomized, noncomparative, parallel-group study was designed to evaluate the pathologic complete response (pCR) rate of combined doxorubicin plus paclitaxel (AP) and doxorubicin plus cyclophosphamide (AC) as neoadjuvant chemotherapy in patients with previously untreated breast cancer who were unsuitable for conservative surgery. PATIENTS AND METHODS: A total of 200 patients with T2-3, N0-1, M0 disease were randomly assigned in a 2:1 ratio to receive preoperative chemotherapy with either doxorubicin 60 mg/m(2) plus paclitaxel 200 mg/m(2) as a 3-hour infusion (AP) or doxorubicin 60 mg/m(2) plus cyclophosphamide 600 mg/m(2) (AC) every 3 weeks for 4 courses followed by surgery. RESULTS: A pCR (eradication of invasive carcinoma in tumor and in axillary lymph nodes) was found in 16% and 10% of patients in the AP and AC arms, respectively, by study center pathologists, and in 8% and 6% of patients, respectively, by independent pathologists. Patients with pCRs tended to have unifocal disease, tumors with negative hormonal receptor status, and less differentiation (Scarff, Bloom, and Richardson scale grade 3). Breast-conserving surgery was performed in 58% and 45% of patients in the AP and AC arms, respectively. An objective clinical response was achieved in 89% of patients in the AP arm and 70% in the AC arm. At a median follow-up of 31 months, disease-free survival (DFS) was higher in patients who reached pCR versus those without pCR (91% v 70%). CONCLUSION: The encouraging pathologic and clinical responses of patients with breast cancer after neoadjuvant chemotherapy with doxorubicin plus paclitaxel warrant additional investigation of paclitaxel in the neoadjuvant setting of breast cancer management.  相似文献   
79.
Family history of autoimmune thyroid disease and childhood acute leukemia.   总被引:1,自引:0,他引:1  
The association between a familial history of autoimmune disease and childhood acute leukemia was investigated in a French case-control study that, overall, was designed to assess the role of perinatal, infectious, environmental, and genetic factors in the etiology of childhood acute leukemia. Familial histories of autoimmune disease in first- and second-degree relatives were compared in 279 incident cases, 240 cases of acute lymphocytic leukemia (ALL) and 39 cases of acute non-lymphoblastic leukemia (ANLL), and 285 controls. Recruitment was frequency matched by age, gender, hospital, and ethnic origin. Odds ratios (OR) were estimated using an unconditional regression model taking into account the stratification variables, socioeconomic status, and familial structure. A statistically significant association between a history of autoimmune disease in first- or second-degree relatives and ALL (OR, 1.7; 95% confidence interval (CI), 1.0-2.8) was found. A relationship between thyroid diseases overall and ALL (OR, 2.0; 95% CI, 1.0-3.9) was observed. This association was more pronounced for potentially autoimmune thyroid diseases (Grave's disease and/or hyperthyroidism and Hashimoto's disease and/or hypothyroidism) (OR, 3.5; 95% CI, 1.1-10.7 and OR, 5.6; 95% CI, 1.0-31.1, respectively for ALL and ANLL), whereas it was not statistically significant for the other thyroid diseases (thyroid goiter, thyroid nodule, and unspecified thyroid disorders) (OR, 1.6; 95% CI, 0.7-3.5 and OR, 1.3; 95% CI, 0.2-7.0, respectively, for ALL and ANLL). The results suggest that a familial history of autoimmune thyroid disease may be associated with childhood acute leukemia.  相似文献   
80.
热性惊厥对大鼠情感行为及学习记忆的影响   总被引:2,自引:2,他引:2  
【目的】 探讨热性惊厥对大鼠情感行为及学习记忆能力的影响。 【方法】  3 6只雄性SD (Spraque Dawley)大鼠随机分为热性惊厥组 (febrileseizuresgroup ,FS) ,发热对照组 (febrilecontrolgroup ,FG)及正常对照组 (nor malcontrolgroup ,NG)。观察各组大鼠在旷场试验 (openfieldtest ,OFT)、避暗试验 (passiveavoidancetest,PAT)以及在Morris水迷宫 (Morriswatermaze ,MWM )试验中情感行为及学习记忆能力的改变。 【结果】 FS组大鼠与NG、FG组相比 :在OFT中穿格得分分值 ( 3 7.48± 7.0 9)降低 ,后肢性站立的次数 ( 12 .11± 4.41)减少 ,排出粪便粒数 ( 10 .62±2 .3 2 )增多 ,差异有非常显著性 (P <0 .0 1) ;在PAT中 ,FS组大鼠犯错次数 ( 4 .0 2± 1.2 9)增加 ,且记忆潜伏期 [( 169.71± 10 3 .2 2 )秒 ]缩短 ,差异有非常显著性 (P <0 .0 1) ;在Morris水迷宫试验中 ,FS组大鼠搜寻站台的逃逸潜伏期明显延长 ,差异有非常显著性 (P <0 .0 1)。 【结论】 多次热性惊厥发作可使大鼠的情感行为和学习记忆能力受损  相似文献   
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