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31.
Deferoxamine-induced growth retardation in patients with thalassemia major   总被引:3,自引:0,他引:3  
In the retrospective study reported here, we compared the longitudinal growth in three groups of children with thalassemia major who received a similar transfusion program but different schedules of chelation treatment. In those patients who initiated deferoxamine (DF) administration by daily subcutaneous infusion (50 to 80 mg/kg/day) simultaneously with the beginning of transfusion (at 8 +/- 6 months), mean height at 2 to 6 years of age was significantly reduced in comparison (1) with those patients who initiated DF subcutaneous treatment after 3 years at similar doses and (2) with those who were treated intramuscularly with small doses. In the patients treated at an early stage, those with more marked stunted growth had a clinical and radiologic ricketslike syndrome associated with joint stiffness. Mineral metabolism studies in these patients showed a reduction of hair and leukocyte zinc levels and leukocyte alkaline phosphatase activity. Our findings indicate that DF administration at high doses by continuous infusion before iron overload has been established adversely affects longitudinal growth. By contrast, after 3 years of age, even large doses (in the order of 100/mg/kg/day) did not result in growth retardation. The growth retardation observed may be related to chelation of other trace elements, including zinc, in the presence of low iron burden, to the direct toxic effect of unchelated DF by interference with critical iron-dependent enzymes, or both. These results indicate that in patients with thalassemia major, DF administration should be initiated only after iron accumulation is established, namely, around 3 years of age, after 20 to 30 transfusions, which are usually associated with ferritin levels in the range of 800 to 1000 ng/ml. At this age, deferoxamine doses should be established on the basis of iron balance studies and dose response curves. Doses higher than 50 to 60 mg/kg do not adversely affect growth but produce toxic side effects on acoustic and visual pathways and therefore should not be used. Longitudinal growth monitoring of DF-treated patients is warranted.  相似文献   
32.
Sub-cellular studies of transmissible spongiform encephalopathies (TSEs) have been carried out on several animal species and human beings. However, studies of optimal perfusion-fixed tissues have largely been confined to examination of rodents. Using a recently developed technique, heads of scrapie-affected sheep and controls were perfusion fixed with mixed aldehydes. The obexes were immunohistochemically labelled with PrP antibodies, and the dorsal motor nucleus of the vagal nerve was examined by electron microscopy. Irregular neuritic profiles with highly invaginated membranes, associated with coated pits were found in all scrapie-affected sheep, but not in controls. Interestingly, they were consistently more frequent in the homozygous A(136) sheep. This is the first report describing sub-cellular differences in pathology associated with different PrP genotypes. Rarely, amorphous material, or sparse fibrillar structures, were present in the extracellular space. The changes were often associated with irregular plasmalemma and frequent coated pits. Vacuolation typical of TSEs, dystrophic neurites and variable gliosis were present. Herniation of membranes and organelles from apparently healthy processes into adjacent vacuoles and dendrites was also observed. We suggest that the increase in coated pits and plasmalemma invagination is related to an attempted internalisation of aggregated disease-specific PrP, or protofilaments, from the extracellular space.  相似文献   
33.

Introduction

Existing methods to detect breast cancer in asymptomatic patients have limitations, and there is a need to develop more accurate and convenient methods. In this study, we investigated whether early detection of breast cancer is possible by analyzing gene-expression patterns in peripheral blood cells.

Methods

Using macroarrays and nearest-shrunken-centroid method, we analyzed the expression pattern of 1,368 genes in peripheral blood cells of 24 women with breast cancer and 32 women with no signs of this disease. The results were validated using a standard leave-one-out cross-validation approach.

Results

We identified a set of 37 genes that correctly predicted the diagnostic class in at least 82% of the samples. The majority of these genes had a decreased expression in samples from breast cancer patients, and predominantly encoded proteins implicated in ribosome production and translation control. In contrast, the expression of some defense-related genes was increased in samples from breast cancer patients.

Conclusion

The results show that a blood-based gene-expression test can be developed to detect breast cancer early in asymptomatic patients. Additional studies with a large sample size, from women both with and without the disease, are warranted to confirm or refute this finding.  相似文献   
34.
Measuring health complaints by administrating a single report is common. Our aim was to assess variation in pain and other subjective complaints over an extended period, whether a single-sample produces representative data, and determine associations between complaints. Health-complaint reports were collected from postal workers at monthly intervals over a period of 32-34 consecutive months (1997-2000). We computed six compound complaint-severity indices of 30 complaint-severity scores (intensity score x duration score, scale 0-9). In 67% of the scores, the complaints exhibited larger deviation from a reference (12 consecutive reports in the last 24 months of the study period) when using one report from the respective reference period compared with the mean of two consecutive reports. Four consecutive samples were needed to obtain agreement for 95% of the data when the criterion of accepted deviation from the reference was set to +/-1.0. Neither inspection of graphs nor statistical tests revealed any seasonal pattern or trend on either a group or individual level. The musculoskeletal and psychological complaint-severity indices correlated strongly (rs > 0.66). Correlations between the different somatic indices were generally weak or moderate (rs < 0.55). The initial report produced higher complaint ratings than subsequent reports did. Due to large intra-individual complaint variability and higher complaint-severity level exhibited on the initial report compared to those that followed, measuring subjective health with a single-sample approach does not produce data representativeness for average complaints over a period. More than two samples should be collected when the purpose is to reveal changes in health.  相似文献   
35.
Australian pregnancy registry of women taking antiepileptic drugs   总被引:1,自引:1,他引:0  
  相似文献   
36.
Preclinical studies have been carried out during the past four decades to investigate the different mechanisms of action of valproate (VPA). The mechanisms of VPA which seem to be of clinical importance include increased GABAergic activity, reduction in excitatory neurotransmission, and modification of monoamines. These mechanisms are discussed in relation to the various clinical uses of the drug. VPA is widely used as an antiepileptic drug with a broad spectrum of activity. In patients, VPA possesses efficacy in the treatment of various epileptic seizures such as absence, myoclonic, and generalized tonic-clonic seizures. It is also effective in the treatment of partial seizures with or without secondary generalization and acutely in status epilepticus. The pharmacokinetic aspects of VPA and the frequent drug interactions between VPA and other drugs are discussed. The available methods for the determination of VPA in body fluids are briefly evaluated. At present, investigations and clinical trials are carried out and evaluated to explore the new indications for VPA in other conditions such as in psychiatric disorders, migraine and neuropathic pain. Furthermore, the toxicity of VPA, both regarding commonly occurring side effects and potential idiosyncratic reactions are described. Derivatives of VPA with improved efficacy and tolerability are in development.  相似文献   
37.
38.
BACKGROUND: The authors assessed the prognostic significance of abnormal cyclin dependent kinase inhibitor (CDKI) expression in adenocarcinomas of the uterine cervix. METHODS: Population-based, archival material from patients with International Federation of Gynecology and Obstetrics (FIGO) Stage I and II cervical adenocarcionmas from 2 5-year periods (1976-1980, n = 82 patients; 1986-1990, n = 142 patients) was examined for expression of p21(WAF1), p27(Kip1), and p16(INK4/MTS1) using immunohistochemical techniques. RESULTS: Rates of tumors with low levels of nuclear expression of p27 and p16 were lower during the period 1976-1980 (P < 0.01), suggesting bias due to unbuffered formalin. Analyses that were restricted to patients from 1986-1990 showed positive associations between all three CDKIs (P < 0.05). Low p16 expression was associated with higher FIGO stage (P = 0.01), age older than 55 years (P = 0.01), and deep invasion (P = 0.003). No significant associations with stage, age, or histopathologic parameters were found for p21 or p27. Significant associations with tumor differentiation were not seen for any CDKI. Kaplan-Meier plots showed diverging survival curves for p21 and p27 expression, but the differences were not significant. In multivariate analysis, low p27 expression and high p16 expression were strong predictors of a poor prognosis (p27: < 40% nuclear staining; P = 0.001; hazard ratio, 3.18; p16: < 40% nuclear staining; P < 0.001; hazard ratio, 0.16). Low p27 expression was of prognostic significance only if it was analyzed together with p16 expression. Further evaluation indicated that patients with different phenotypic p27/p16 combinations may have different outcomes. CONCLUSIONS: Aberrant expression patterns of CDKIs were predictors of prognosis for patients with FIGO Stage I or II cervical adenocarcinoma. Analysis of CDKI expression in this patient group may prove clinically useful.  相似文献   
39.
40.
Manchiraju et al. (International Journal of Mental Health and Addiction, 1–15, 2016) published the Compulsive Online Shopping Scale (COSS) in the International Journal of Mental Health and Addiction (IJMHA). To develop their measure of compulsive online shopping, Manchiraju and colleagues adapted items from the seven-item Bergen Shopping Addiction Scale (BSAS) and its’ original 28-item item pool. Manchiraju et al. did not add or remove any of the original seven items, and did not substantially change the content of any of the 28 items on which the BSAS was based. They simply added the word “online” to each existing item. Given that the BSAS was specifically developed to take into account the different ways in which people now shop and to include both online and offline shopping, there does not seem to be a good rationale for developing an online version of the BSAS. It is argued that the COSS is not really an adaptation of the BSAS but an almost identical instrument based on the original 28-item pool.  相似文献   
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