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91.
Human epidermis consists of a stratified epithelium mainly composed of keratinocytes and relies on a stem cell compartment to undergo constant regeneration. Genetic mutations affecting the capacity of basal keratinocytes to adhere firmly to the epidermal basement membrane lead to severe, and very often lethal, blistering disorders known as epidermolysis bullosa. Gene therapy represents a promising potential treatment for these devastating inherited disorders. Human epidermal stem cells can be cultivated ex vivo and stably transduced with integrating gene transfer vectors, allowing genetic and, more important, phenotypic correction of the adhesion properties of keratinocytes. Here we will review some of the issues that need to be addressed to make gene therapy a realistic treatment for these disorders, such as (1) which cells should be targeted, (2) which approach (in vivo or ex vivo) should be chosen, and (3) which gene transfer vector (retrovirus, lentivirus, or integrating nonviral strategies) should be used for stable gene correction. In the last 10 years, many reports have shown that gene transfer approaches to target epidermal stem cells are feasible and able to restore the adhesion properties of primary keratinocytes from patients with epidermolysis bullosa. In addition, tremendous progress has been achieved in culturing epidermal stem cells and generating sheets of stratified epithelium for permanent coverage of full-thickness burns. Gene modification of stem cells in combination with advanced tissue-engineering techniques could therefore represent a realistic option for patients with epidermolysis bullosa.  相似文献   
92.
A prospective study was performed to investigate the changes in nasal cytology that occur in healthy premenopausal women throughout the menstrual cycle. Eighty-eight women with an ovulatory menstrual cycle underwent nasal sampling with a cytobrush by direct vision of the middle and inferior nasal turbinates during the follicular, periovular, and luteal phases of the menstrual cycle, and the specimens were evaluated with the maturation index. Hematoxylin-eosin staining showed the cytologic aspects of the nasal respiratory epithelium and of vaginal smears according to the three different phases of the menstrual cycle. Along with the vaginal cells, the nasal respiratory epithelium is an ovarian steroid target.  相似文献   
93.
Disproportionate heart muscle enlargement compared with little or no chamber enlargement are characteristic for hypertrophic cardiomyopathy (HCM). The clinical course of HCM is highly variable. Many patients are asymptomatic or mildly symptomatic and may be relatives of patients with known disease. Unfortunately, the first clinical manifestation of the disease may be sudden death, frequently occurring in children and young adults, often during or after physical exertion. We present 2 cases of HCM who emphasize the variability of clinical and ECG modifications and underline the importance of routine echocardiography in patients with atypical cardiac symptoms in order to identify the disease and prevent high risk for sudden death.  相似文献   
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95.
OBJECTIVE: The aim of this study was to assess in an 11-year survival follow-up of a population-based cohort of type 2 diabetes the predictive role of World Health Organization-defined metabolic syndrome, independent of conventional cardiovascular risk factors. RESEARCH DESIGN AND METHODS: During the follow-up (1991-2001), 1,565 patients were regularly examined with centralized measurements of HbA(1c). The independent role of the metabolic syndrome as a predictor of all-cause and cardiovascular mortality was assessed with multivariate Cox proportional hazards modeling. RESULTS: At baseline, the prevalence of the metabolic syndrome was 75.6% (95% CI 73.6-77.9). Results are based on 685 deaths (520 with the metabolic syndrome and 165 without it) in 10,890.2 person-years of observations. With respect to subjects without the metabolic syndrome, those with the metabolic syndrome had a similar hazard ratio (HR) of cardiovascular mortality after adjustment for age, sex, smoking, total cholesterol level, and coronary heart disease. In contrast, relative to subjects with diabetes only, the HR of subjects with only one component of the syndrome was 2.92 (1.16-7.33), independent of other risk factors. CONCLUSIONS: We found that 1) the prevalence of the metabolic syndrome in a population-based cohort of type 2 diabetes is high (75.6%); 2) the metabolic syndrome is not a predictor of 11-year all-cause and cardiovascular mortality; and 3) more than twofold higher cardiovascular risk, independent of conventional risk factors, is evident in diabetic subjects with only one component of the syndrome compared with those with diabetes only. Categorizing type 2 diabetic subjects as having or not having the metabolic syndrome does not provide further prediction compared with the knowledge of its single components.  相似文献   
96.
97.
The aim of the present study was to verify the clinical efficacy of melatonin (MLT) in children, adolescents and young adults with wake-sleep disorder and mental retardation, most of them on chronic anticonvulsant therapy for epileptic seizures, by means of a randomized, double-blind, placebo-controlled cross-over trial. Twenty-five patients (16 males, nine females), aged from 3.6 to 26 years (mean 10.5 years), all affected with mental retardation mostly with epileptic seizures, were randomized to oral synthetic fast-release MLT or placebo. Melatonin was initiated at the daily dose of 3 mg, at nocturnal bedtime. In case of inefficacy, MLT dose could be titrated up to 9 mg the following 2 weeks at increments of 3 mg/week, unless the patient was unable to tolerate it. The analysis of all the sleep logs disclosed a significant treatment effect of melatonin on sleep latency (P = 0.019). Melatonin was well tolerated in all patients and no side effects were reported. In conclusion, our study supports the efficacy of MLT in young patients with mental disabilities and epileptic seizures in improving the wake-sleep disorders such as time to fall asleep. Overall, MLT appeared to influence the seizure frequency poorly, though there may be occasional seizure worsening or improving. Such a dual effect requires further studies in young epileptic patients.  相似文献   
98.
OBJECTIVE: To assess the annual incidence of typical Guillain-Barré syndrome (GBS) and its main variants (atypical GBS) in a well-defined population from a large area. MATERIAL AND METHODS: A population-based prospective survey of GBS was undertaken during the calendar year 1996 in Lombardy, Italy (population 8,891,652). Typical and atypical GBS was diagnosed using the National Institutes of Neurological and Communicative Disorders and Stroke (NINCDS) and Ropper criteria. Eligible cases were hospital inpatients traced through a regional registry, the hospital discharge diagnoses, and an ongoing case-control study. Diagnostic and demographic findings were collected for each case. Complete clinical and laboratory features were available for 80% of cases. RESULTS: A total of 138 patients (males 74; females 64) aged 2-91 years fulfilled the diagnostic criteria for typical GBS (128) or atypical GBS (10). GBS variants included Miller-Fisher syndrome (four cases), cranial polyneuritis (three cases), pure motor GBS (two cases), and sensory loss with areflexia (one case). The crude annual incidence of GBS was 1.55 per 100,000 (typical GBS 1.43; atypical GBS 0.11; male 1.67; female 1.43; age <35 years, 0.79; 35-54 years, 1.33; 55-74 years, 3.22; 75+ years, 4.67). The overall rate was 1.58 when age- and sex-adjusted to the 1996 Italian population. Previous infections were reported for 37% of patients. The electrophysiological findings indicated demyelination in 51%, primary axonopathy in 14%, and mixed myelin and axon involvement in 27%. CONCLUSIONS: The incidence of typical GBS is comparable with that in other reports using the NINCDS diagnostic criteria. Atypical GBS accounts for a limited number of cases.  相似文献   
99.
BACKGROUND: The period in utero is a time of increased vulnerability. Offspring of pregnant women exposed to carcinogenic substances in drinking water may be more likely to develop cancer. We examined whether household water source and the presence of nitrates or nitrites in residential water were associated with increased risks of childhood brain tumours (CBT). METHODS: We used data from a multicentre, case-control study with maternal information on residential water source, and nitrate/nitrite levels of tap water measured by dipstick. Subjects included 836 CBT cases and 1485 controls from five countries. RESULTS: The risks of CBT associated with reliance on well water (versus public water) during pregnancy varied widely, with significantly increased risks noted in two (of seven) regions and a decreased risk observed in one region. CBT risk did not increase with increasing nitrate levels. However, our results based on tap water tested in the pregnancy residences suggest the risk of astrocytoma may be associated with increasing levels of nitrite (odds ratio [OR] = 4.3, 95% CI: 1.4, 12.6 for nitrite levels of 1-<5 mg/l nitrite ion; OR = 5.7, 95% CI: 1.2, 27.2 of nitrite > or =5 mg/l). CONCLUSIONS: These results should be interpreted with caution because women's recollection of water sources may have contained inaccuracies, and nitrate and nitrite measurements, available for only a portion of subjects, were often obtained years after the pregnancies occurred. However, our results suggest a need for closer evaluation of well water content in some regions and the possibility that a nitrite-related water exposure may be associated with CBT.  相似文献   
100.
When vestibular damage occurs, nitric oxide synthase (NOS) expression in rat cerebellar flocculus is affected. Since compensation for postural symptoms occurs and Purkinje cells play an important role in movement coordination and motor learning, we analyzed in situ the induction of NOS in the Purkinje cell population of the cerebellum (corpus cerebelli) of frog after unilateral transection of the eighth statoacoustic nerve to gain insight into the role of NO in neural plasticity after injury. Three days after neurectomy, the early effects induced NADPH diaphorase reactivity in most of the Purkinje cells on the ipsilateral side, while on the contralateral side the highest labeling was observed at 15 days. This finding can give information on the dynamics of vestibular compensation, in which NOS involvement was investigated. At 30 days, NADPH diaphorase reactivity was present in a large number of Purkinje cells of the whole cerebellum, while at 60 days a down-regulation for NADPH diaphorase reactivity was evident. A similar trend was observed for NOS-immunoreactivity, which was still present at 60 days in a high percentage of Purkinje cells, mainly on the ipsilateral side. On the basis of cell density evaluations, it was proposed that the early induction of NOS after neurectomy was linked to the degeneration of a part of the Purkinje neurons, while the permanence of NOS labeling might be due to a neuroprotective role of NO in the restoration phase of the vestibular compensation process.  相似文献   
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