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Intranasal (IN) delivery of HIV-1 Tat in aging mice was investigated as a possible model for HIV-1 infection in the brain. After IN administration, the distribution of [125I]-labeled Tat in the brains of Swiss Webster mice was evaluated by autoradiography and gamma counting. [125I]-labeled Tat was detected at the highest concentrations in the olfactory bulb, cervical nodes, and trigeminal nerve tract. In another experiment, APPSw transgenic mice were used to model chronic Tat exposure. The mice were treated intranasally with 6 μg Tat (n = 4) or vehicle (n = 4) three times per week for 4 weeks. Total RNA was isolated from the frontal cortex, and differential gene expression analysis was performed using gene microarrays. Gene ontology profiles indicated innate immunity, inflammatory and apoptotic responses. Five genes of interest in the Tat-treated mice that were significantly elevated in the microarrays were validated by RT-PCR. One gene, the Toll-like receptor 9 (Tlr9), has previously been shown to activate signaling cascades leading to innate immunity and enhanced HIV-1 gene expression. A second gene, Fas, plays a key role in neuroinflammation. Two cysteine-rich cytokines associated with chemotaxis were elevated: MCP-1 (Ccl2), which is chemotactic for monocytes, and Ccl17 (TARC), which is chemotactic for lymphocytes. Finally, the gene sestrin was significantly elevated and has been associated with oxidative stress, in particular amyloid beta-induced oxidative stress. This IN Tat model of neuroinflammation may be useful to study HIV-1-induced neurodegeneration. This paper was presented at an NIMH workshop “HIV Preclinical–Clinical Therapeutics Research Meeting”, May 5–16, 2006.  相似文献   
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The 5-HT(1A) receptor is a well-characterized serotonin receptor playing a role in many central nervous functions and known to be involved in depression and other mental disorders. In situ hybridization, immunocytochemical, and binding studies have shown that the 5-HT(1A) receptor is widely distributed in the rat brain, with a particularly high density in the limbic system. The receptor's localization in the different neuronal subtypes, which may be of importance for understanding its role in neuronal circuitries, is, however, unknown. In this study we show by immunocytochemical double-labeling techniques, that the 5-HT(1A) receptor is present on both pyramidal and principal cells, and calbindin- and parvalbumin-containing neurons, which generally define two different subtypes of interneurons. Moreover, semiquantitative analysis showed that the receptor's distribution in the different neuronal types varies between brain areas. In cortex, hippocampus, hypothalamus, and amygdala the receptor was located on both principal cells and calbindin- and parvalbumin-containing neurons. In septum and thalamus, the receptor was mostly present on calbindin- and parvalbumin-containing cells. Especially in the medial septum and thalamic reticular nucleus, the receptor highly colocalized with parvalbumin-positive neurons. These results suggest a diverse function of the 5-HT(1A) receptor in modulating neuronal circuitry in different brain areas, that may depend on the type of neuron the receptor is predominantly located on.  相似文献   
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This study addresses the utility of fine-needle aspiration (FNA) in assessing lymphadenopathy in patients with and without a previous history of malignancy. We reviewed the FNAs of superficial and deeply seated lymph nodes performed at our institution over a period of 18 yr (1983-2001). Where applicable, we also reviewed and report here the results of subsequent surgical excisional biopsies. We analyzed data from 439 patients, who ranged in age from 1 to 90 yr. The neck and retroperitoneum were the most frequently sampled sites (47% and 25%, respectively). Among the 439 FNAs, adequate material was obtained in 421 cases (96%); the remaining 18 were unsatisfactory (4.1%). Malignant diagnoses were rendered in 330 cases (75% of 439), four were suspicious for lymphoma (0.9%), and 87 were read as reactive lymph nodes or granulomas (20%). The most common malignant cytologic diagnoses from these lymph node FNAs were adenocarcinoma, squamous cell carcinoma, and lymphoma. We compared results between two major groups: patients with a history of malignancy and those without. FNA showed malignancy in 87% of patients with a history of cancer and 41% without such a history. Thirty-three or 10% of patients with a history of malignancy were given a benign diagnosis and follow-up surgical excisional biopsies were performed in nine of these cases. Four of the nine showed low-grade lymphoma. Of the 18 non-diagnostic FNAs, nine came from patients with a history of malignancy and in six of these nine who had a follow-up surgical excisional biopsy the lymph nodes were positive for malignancy. Of the other nine, who had no history of malignancy, only two had follow-up biopsies and both of these were negative. Patients with a history of malignancy are more than twice as likely to show malignancy on lymph node FNA compared to those without such a history (87% vs. 41%). Knowing whether a patient has a history of malignancy provides the appropriate level of suspicion for ordering ancillary investigations or even recommending excisional biopsy for further evaluation.  相似文献   
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This study was undertaken to test the hypothesis that basal sympathetic activity and sympathetic reactivity to stress are increased in patients with essential hypertension. One hundred and fifteen randomly selected patients with essential hypertension and an equal number of age- and sex-matched normal controls were included in this study. Various parameters, viz., heart rate, respiratory rate, blood pressure, peripheral skin temperature, electromyographic activity of the frontalis muscle, skin conductance (measured by electrodermography), and blood pressure, were measured in the resting state in both groups. These parameters were then measured during the performance of various stressful activities, such as mental arithmetical calculations, thinking of unpleasant thoughts, staring at a fixed point, catching of a dropped object, and reading aloud for 1 min each, and again over a 1-min quiet period following each stressful activity. Changes in various parameters in the two groups were analyzed and compared. Baseline heart rate, respiratory rate, electromyographic activity and peripheral skin temperature were higher-while skin conductance was lower-in the hypertensive group than in the control group. The increases in systolic blood pressure, diastolic blood pressure, heart rate, respiratory rate, electromyographic activity, and peripheral skin temperature in response to stress were greater in hypertensive patients than in controls, while skin conductance showed a higher elevation in controls than in hypertensive patients. In conclusion, sympathetic nervous system activity is increased in patients with essential hypertension. The reduced skin conductance and high peripheral skin temperature in these patients may be due to a possible dermal neurovascular dysfunction.  相似文献   
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The purpose of this study was to determine if any relationship exists between Her-2/neu gene amplification and estrogen receptor (ER), progesterone receptor (PR), MIB-1, grade, size and age in female breast cancer. Five hundred and eighteen female patients with invasive breast carcinoma, 390 ductal and 128 lobular, in which assessment of Her-2/neu amplification by fluorescence in-situ hybridization (FISH) has been performed, were reviewed retrospectively. Each patient was further assessed for ER, PR, MIB-1, grade, size and age at diagnosis. Chi-square analysis was then used to correlate the above observations. Overall gene amplification was seen in 76 (15%) of the cases, 68 (17%) were ductal and 8 (6%) were lobular. Her-2/neu gene was amplified in 37 (10%) out of 379 ER positive cases and in 39 (28%) out of 139 ER negative cases. Her-2/neu was amplified in 22 (7%) out of 301 PR positive cases and in 54 (25%) out of 217 PR negative cases. Amplification occurred in 18 (8%) out of 222 negative MIB-1 cases and amplified in 58 (20%) out of 296 positive cases. Amplification was seen in 5 (10%) out of 49 grade I tumors, 17 (12%) out of 143 grade II tumors and 54 (27%) out of 198 grade III tumors. Lobular carcinomas were not graded. Amplification was present in 52 (15%) out of 346 T1 lesions, in 17 (13%) out of 130 T2 lesions, in 5 (17%) out of 30 T3 lesions and in 2 (17%) out of 12 T4 lesions. Her-2/neu was amplified in 67 (14%) out of 467 woman 41 years and older, and in 9 (18%) out of 51 women 40 years and younger. Comparison of these frequencies using chi-square test revealed statistically significant correlation between Her-2/neu amplification and ductal versus lobular carcinoma (p<0.0003), ER (p=0.0001) and PR (p<0.0001) negative tumors, over-expression of MIB-1 (p<0.0005) and high tumor grade (p=0.0009), while size of the tumor (p=0.08) and age of the patients (p=0.67) were not statistically significant. Correlation was found between Her-2/neu amplification and tumor type, high histological grade, ER and PR negative tumors, and high proliferative MIB-1 index. No correlation was found between size of the tumor and age of the patient with Her-2/neu amplification.  相似文献   
28.
Pharmacoepidemiology of anemia in kidney transplant recipients   总被引:11,自引:0,他引:11  
ABSTRACT. Anemia has long been known to be a complication of end-stage renal disease (ESRD), and it has been linked to cardiovascular morbidity and mortality. Although kidney transplant recipients (KTR) are prone to experiencing cardiovascular outcomes, little is known about the epidemiology of anemia in this population. With few exceptions, studies to date have not fully evaluated the associations between posttransplant anemia (PTA) and medications commonly used in KTR, particularly immunosuppressant drugs, angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARB). The authors aimed to specifically investigate possible associations between these drugs and PTA. Detailed medical information was retrospectively collected on 374 consecutive KTR from our transplant clinic. Univariate/multivariate linear regression models were used to test for associations between hematocrit (HCT) and other covariates, and logistic regression models were used to detect independent predictors of PTA, defined as HCT <33%. The mean time since transplantation was 7.7 yr, and mean creatinine was 2.2 mg/dl. The prevalence of PTA was 28.6%. Ten percent of all patients were on erythropoietin therapy, but only 41.6% of patients whose HCT was <30 received this treatment. From multivariate analyses, the authors found that female gender and lower renal function were associated with lower HCT (both P < 0.001). Patients on ACEI had significantly lower HCT (P = 0.005) compared with patients without such treatment. In addition, a significant curvilinear dose-response relationship was found between ACEI dose and HCT. Among the immunosuppressant drugs, mycophenolate mofetil (P = 0.05) and tacrolimus (P = 0.02) were associated with a lower HCT. The authors conclude that PTA is prevalent and undertreated in KTR. Several medications that are possibly modifiable correlates of PTR deserve further study.  相似文献   
29.
OBJECTIVE: There are few analytical results that describe patient compliance with drug administration regimens. The purpose of this paper is to develop and assess stochastic approaches for mathematical modelling of patient compliance with administration regimens. METHODS: Two stochastic models based on Markov-dependent random variables and on the Ising model were assessed for their ability to describe the variable nature of drug compliance. RESULTS: Both models use only experimentally accessible data, and their predictions were tested against published clinical compliance data obtained from electronic monitoring devices. The models satisfactorily fitted administration interval distribution data from several patients treated with diltiazem, a calcium channel antagonist, or zidovudine, an antiretroviral agent. The Ising model provides additional analytical expressions for the distribution of success runs and 'drug holidays' in administration regimens. These distribution predictions were tested with success run data for diltiazem and drug holiday data for two nonsteroidal anti-inflammatory drugs, piroxicam and tenoxicam. CONCLUSIONS: Stochastic models can provide useful insights into drug compliance, and can be used to identify the administration patterns that are more likely to occur during drug self-administration in populations.  相似文献   
30.
STUDY OBJECTIVE: To describe our experience and technique of total laparoscopic radical hysterectomy with pelvic lymphadenectomy, which is the largest single- institution study. DESIGN: Retrospective, nonrandomized study (Canadian Task Force classification II-2). SETTING: Private hospital. PATIENTS: Two hundred forty-eight patients with International Federation of Gynecology and Obstetrics stage IA2 (n = 32) and IB1 (n = 216) of cancer of the cervix. INTERVENTION: Total laparoscopic type III radical hysterectomy with bilateral pelvic lymphadenectomy was done. Simple repetitive steps were used to perform this surgery and develop an easily replicable technique. Harmonic Shears, bipolar coagulation, and vascular clips were used. Resection of the cardinal and uterosacral ligaments was performed with LigaSure (LigaSure Vessel Sealing System; Valleylab, Tyco Healthcare, Boulder, CO) or the Harmonic Shears (Ethicon Endo-Surgery, Inc., Cincinnati, OH). Pelvic lymph node dissection was done. MEASUREMENTS AND MAIN RESULTS: Histopathologically, there were 183 (73%) cases of squamous carcinoma, 52 (20%) adenocarcinomas, and 13 (5%) adenosquamous carcinomas. Four patients needing anterior exenteration because of bladder involvement were excluded from data analyses. The operation was performed entirely by laparoscopy in all patients and by the same surgical team. The patients' median age was 61 years. The median operative time was 92 minutes (range 65-120 minutes). The median number of resected pelvic nodes was 18. The median blood loss was 165 mL. The median length of stay was 3 days. All 15 intraoperative complications were tackled laparoscopically. No patients were converted to the open technique. There were no deaths in our series. Seventeen patients had complications within 2 months of surgery. Seven patients had recurrences after a median follow-up of 36 months. CONCLUSION: Our technique of total laparoscopic radical hysterectomy, developed over 248 cases, can be performed safely. It is an easily replicable technique. This procedure reduces the morbidity associated with abdominal radical hysterectomy. All of the complications can also be tackled laparoscopically, which does not further add to the morbidity.  相似文献   
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