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21.
The human small-conductance Ca(2+)-activated potassium channel gene KCNN3 has been involved in mechanisms underlying neuronal function and plasticity. A multiallelic CAG repeat polymorphism within the KCNN3 has been associated with schizophrenia and bipolar disorder. We have previously reported in a family-based study that longer CAG repeats are preferentially transmitted to patients with anorexia nervosa (AN). The present study extends the analysis of KCNN3 allele distribution to a larger series of AN female patients and control groups, incorporating information on ethnicity and co-morbidities associated with AN. The data analysis is presented while considering separately the two alleles of each individual, namely a minor (shorter) and a major (longer) allele. This study has found that the KCNN3 allele distribution in the general Israeli population does not differ significantly in at least four Jewish ethnic groups of Ashkenazi, North African, Iraqi, and Yemenite origin. These have been used as control groups in a matched case-control analysis that has demonstrated a significant over-representation of KCNN3 alleles with longer CAG repeats among AN patients (P < 0.001 for the major allele and P = 0.035 for allele sum). Under dichotomization, a significantly higher prevalence of the L allele (>19 repeats) has been observed among AN patients (P < 0.001). While considering AN and co-morbid phenotypes, a tendency towards longer (L) alleles has been observed in the subset of patients with obsessive-compulsive disorder (OCD) co-morbidity. These findings further implicate KCNN3 as a significant contributor to predisposition to AN.  相似文献   
22.
Postoperative radiotherapy for locally advanced colon cancer   总被引:1,自引:0,他引:1  
Background: The role of adjuvant postoperative radiotherapy for locally advanced colon cancer is not well documented. Methods: Seventy-eight patients who underwent a complete resection of B2-C colon cancer received postoperative radiotherapy. Twenty-eight patients received ⩽45 Gy; 50 patients received 50–55 Gy. Twenty-seven patients received adjuvant fluorouracil-based chemotherapy. All patients were followed for a minimum of 3 years; no patients were lost to follow-up. Results: The overall local control rate was 88%. The 5-year actuarial rate of local control was 96% after 50–55 Gy postoperative radiotherapy compared with 76% after <50 Gy (p=0.0095). Multivariate analysis of local control showed that only radiotherapy dose significantly influenced this end point. Cause-specific survival rates at 5 years were B2, 67%; B3, 90%; C1, 100%; C2, 61%; C3, 36%; and overall, 63%. Multivariate analysis of cause-specific survival showed that only stage significantly influenced this end point. Bowel obstruction caused by adhesions developed in three patients and required a laparotomy; radiation-induced sarcoma developed in one additional patient. Conclusions: Postoperative radiotherapy appears to reduce the risk of local recurrence in patients with locally advanced colon cancer. The optimal dose is probably 50–55 Gy at 1.8 Gy per fraction. Postoperative radiotherapy may improve cause-specific survival for patients with stages B3 and C2 cancers.  相似文献   
23.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
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In this study we evaluated the comparative efficacy of free and liposomally conjugated methotrexate on both disease induction and suppression of acute inflammation in rat adjuvant-induced arthritis. Rats were given either empty liposomes (E-LIPO), free methotrexate (MTX) or the liposomally conjugated methotrexate (MTX-LIPO) at a dose of 100 micrograms/day for 7 consecutive days by the intravenous route. When MTX treatment was initiated on the day of arthritis induction the drug suppressed but did not abolish the development of joint inflammation. Free MTX had no significant anti-inflammatory effect upon an established arthritis when dosing was commenced on day 11 post-adjuvant induction. Conversely, MTX-LIPO did not affect the progression of the arthritis when dosing was started on day 0, but exerted a significant anti-inflammatory effect on an established arthritis. MTX-LIPO treatment was significantly less haematotoxic than free MTX.  相似文献   
27.
Simultaneous turnover of normal and dysfunctional C1-inhibitor (C1-INH) was carried out in 10 normal subjects and 13 patients with rheumatoid arthritis as a measure of the in vivo activation of C1 and the contact activatable enzymes. In the first series of experiments, dysfunctional protein We was used in simultaneous turnover studies in five normal subjects and nine patients. The fractional catabolic rate of the dysfunctional C1-INH, We, (FCR(d)) was unchanged in both groups but the fractional catabolic rate of the normal C1-INH (FCR(n)) was faster in the patients compared to the controls, in particular patients with vasculitis. The enzyme-dependent catabolism defined as FCR(n-d) X concentration of C1-INH X plasma volume, was raised in the patient group, and correlated with disease activity score (r = 0.83, P less than 0.05). Neither FCR(n) nor FCR(d) was dependent on C1-INH concentration. The latter was higher in the patients (206 mg/l compared with 155 mg/l) indicating a very high synthetic rate in the patients (280.81 micrograms/kg/h compared with 179.77 micrograms/kg). In the second series of turnovers in six patients and five normal subjects, another dysfunctional C1-INH, at, was used. The FCR of C1-INH was slower than C1-INH (We) (1.88%/h compared with 2.7%/h). Enzyme-dependent catabolism of C1-INH in these patients were raised and also correlated with disease activity score (r = 0.82, P less than 0.05).  相似文献   
28.
The free radical-generating system of xanthine and xanthine oxidase is commonly used experimentally as a source of superoxide anion, which can produce oxidative stress, leading to cellular damage and death. Models of oxidative stress are important in elucidating pathologies associated with increased levels of reactive oxygen species, including stroke and neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. We therefore, examined the effect of the xanthine/xanthine oxidase system on the viability of postnatal cerebellar granule neurones obtained from 8-day old Sprague–Dawley rat pups. Xanthine (100 μM) and xanthine oxidase (0.02 U/ml) applied for 1 or 6 h reduced the viability of cells at 8 div assessed using the alamar blue assay, and induced morphological changes, such as shrinkage of the cell bodies and neurites. Heat-inactivation of xanthine oxidase resulted in complete loss of its activity. Superoxide dismutase (250 U/ml) failed to modify the damage by xanthine and xanthine oxidase, while catalase (250 U/ml) completely prevented it. When applied alone, xanthine oxidase significantly lowered cell viability, an effect that was blocked by allopurinol and catalase, but not by superoxide dismutase. The results indicate that xanthine and xanthine oxidase can produce predominantly hydrogen peroxide instead of the superoxide anion. Cerebellar granule cells in culture may also possess significant levels of endogenous xanthine.  相似文献   
29.
We performed genetic analysis for carrier detection for several at-risk females in a four-generation Duchenne muscular dystrophy (DMD) pedigree using deletion analysis. We demonstrated that dosage analysis is a suitable alternative method to determine the carrier status of female relatives of DMD patients shown to have a deletion within the DMD gene. Subsequently, we diagnosed an affected male fetus for an at-risk female shown to be a DMD carrier by deletion analysis. The usefulness of deletion and linkage analysis are compared. In this family, linkage analysis was complicated by the unavailability of key family members, two recombination events and by previously undisclosed nonpaternity. We found that dosage analysis was more efficient than linkage for carrier evaluation in this family.  相似文献   
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