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991.
Nephrogenic metaplasia or nephrogenic adenoma of the urinary tract may present a diagnostic challenge in surgical pathology practice. Previous case reports suggest the possibility of nephrogenic metaplasia progressing to clear cell adenocarcinoma, but a malignant potential of nephrogenic metaplasia is generally not acknowledged. A case of a 70-year-old female patient with multiple recurrences of nephrogenic metaplasia of the urinary bladder and subsequent development of clear cell adenocarcinoma is described. Immunohistochemical studies help to differentiate the 2 entities. Results of molecular studies, particularly comparative genomic hybridization analysis, suggest clonal evolution of nephrogenic metaplasia to clear cell adenocarcinoma in this case.  相似文献   
992.
BACKGROUND: The induction of tolerance may be a promising target of strategies aimed at preventing harmful allergic diseases. Low zone tolerance (LZT), induced by epicutaneous application of low doses of contact allergens, inhibits the development of T(C)1-mediated contact hypersensitivity (CHS). OBJECTIVE: We evaluated the effect of systemic (oral, intravenous) administration of low amounts of haptens on specific immune reactions and tolerance induction. METHODS: By using the mouse model of LZT, we analyzed immune reactions in vivo (skin inflammation) and T-cell responses in vitro after oral, intravenous, or epicutaneous application of low amounts of the contact allergen 2,4,6-trinitro-1-chlorobenzene (TNCB). RESULTS: Subimmunogenic doses of TNCB applied orally and intravenously induced a significant tolerance reaction in vivo comparable to epicutaneously tolerized mice, indicating that LZT is a systemically mediated tolerance reaction. In vitro analysis in all models of LZT revealed the generation of IL-10 secreting, regulatory CD4+ T cells that were absolutely required for the development of hapten-specific CD8+ T(C)2 cells. Adoptive transfer experiments identified CD8+ T(C)2 cells as effector T cells of LZT inhibiting the development of CHS-promoting T(C)1 cells and consequently the manifestation of CHS. These suppressor CD8+ T(C)2 cells were found as well in skin-draining as in mesenteric lymph nodes and in the spleen of tolerized animals independent of the route of tolerization. CONCLUSION: These data indicate that systemic uptake and presentation of small amounts of haptens (eg, contact allergens, drugs, metals) induce the development of LZT and thus prevent inappropriate activation of the immune system and protect from allergic diseases. CLINICAL IMPLICATIONS: These findings will be of particular importance because tolerance induction by protocols applying subimmunogenic, low amounts of haptens may be used as tools for immunotherapy in allergic and autoimmune diseases.  相似文献   
993.
Different aspects of the environmental tobacco smoke (ETS) exposure of children in Germany have been investigated in the German Environmental Survey for Children (GerES IV). The field work of GerES IV was conducted from 2003 to 2006 using questionnaires, indoor air monitoring and human biomonitoring.  相似文献   
994.
Evaluation of the prenatal toxicity of a substance in rats or other animals according to the current guidelines is often hampered by the rapid metabolism of the test compound and/or by maternal toxicity. One example for such a compound is moxifloxacin. In vitro systems offer the possibility to study the direct effects of the test compound on embryonic tissues. The aim of this study was to evaluate the embryotoxic potential of moxifloxacin in vitro using the murine limb bud culture. Clinafloxacin, which was found to be teratogenic when tested in rats, was used for comparison. The effects of various concentrations of moxifloxacin (10, 30, 60 and 100 mg/L) and clinafloxacin (3, 10 and 30 mg/L) on growth and differentiation of 12–day-old murine limb buds were studied in a standard and in a magnesium-deficient medium. After termination of the culture, the respective front limb buds were examined by different methods. Clinafloxacin showed clear-cut effects at a concentration of 30 mg/L in both media. Effects were similarly pronounced as the effects observed with moxifloxacin at a concentration of 100 mg/L. Lower concentrations of moxifloxacin, which are achieved during therapy in humans, did not impair growth and differentiation of limb buds. Using electron microscopy, slight ultrastructural changes could be seen after exposure to 3 mg clinafloxacin/L medium. Ultrastructurally, clinafloxacin caused a concentration-dependent decrease of the extracellular matrix, swelling of cell organelles and at higher concentrations necrotic chondrocytes. These effects were significantly enhanced in a magnesium-deficient medium. In conclusion, the effects of moxifloxacin on murine limb buds in vitro were definitely less pronounced than those of clinafloxacin. Effects on growth and differentiation occurred with moxifloxacin only at concentrations that are higher than plasma concentrations observed during therapy. This result is of special interest, because due to rapid metabolism of moxifloxacin in rats results from a routinely performed segment II type study cannot be used for a risk assessment.  相似文献   
995.
Background: Erythropoietic protoporphyria (EPP) is the most common porphyria in childhood, presenting with painful and burning skin sensations as well as erythema and edema after sun exposure. It represents an inherited disorder of heme metabolism that is due to a reduced ferrochelatase enzyme activity. The diagnosis is usually established when symptoms start by measuring elevated levels of protoporphyrin in erythrocytes. The aim of our study was to question the predictive value of cord blood analysis in newborn relatives of EPP patients as this may offer the earliest possible diagnosis of EPP in newborn relatives of affected patients.
Methods: Erythrocyte porphyrin (EP) was measured immediately after birth in 18 newborn relatives of EPP patients. EP was correlated to the subsequent clinical follow-up of mean 9 years after birth.
Results: We found EP to be within reference values in all 18 newborn relatives of EPP patients at birth. Out of 14 patients who were included in the follow-up period of median 9 years, 13 remained asymptomatic whereas one boy developed the typical symptoms of EPP at the age of three in combination with elevated EP.
Conclusion: Based on the findings of our study, we assume that cord blood analysis is not a reliable prognostic tool in EPP from the actual point of view.  相似文献   
996.
997.

Background

The arterial switch operation (ASO) is currently the treatment of choice in neonates with transposition of the great arteries (TGA). The outcome in childhood is encouraging but only limited data for long-term outcome into adulthood exist.

Methods and results

We studied 145 adult patients (age > 16, median 25 years) with ASO followed at our institution. Three patients died in adulthood (mortality 2.4/1000-patient-years). Most patients were asymptomatic and had normal left ventricular function. Coronary lesions requiring interventions were rare (3 patients) and in most patients related to previous surgery. There were no acute coronary syndromes. Aortic root dilatation was frequent (56% patients) but rarely significant (> 45 mm in 3 patients, maximal-diameter 49 mm) and appeared not to be progressive. There were no acute aortic events and no patient required elective aortic root surgery. Progressive neo-aortic-valve dysfunction was not observed in our cohort and only 1 patient required neo-aortic-valve replacement. Many patients (42.1%), however, had significant residual lesions or required reintervention in adulthood. Right ventricular outflow tract lesions or dysfunction of the neo-pulmonary-valve were frequent and 8 patients (6%) required neo-pulmonary-valve replacement. Cardiac interventions during childhood (OR 3.0, 95% CI 1.7–5.4, P < 0.0001) were strong predictors of outcome (cardiac intervention/significant residual lesion/death) in adulthood.

Conclusions

Adult patients with previous ASO remain free of acute coronary or aortic complications and have low mortality. However, a large proportion of patients require re-interventions or present with significant right sided lesions. Life-long cardiac follow-up is, therefore, warranted. Periodic noninvasive surveillance for coronary complications appears to be safe in adult ASO patients.  相似文献   
998.
999.
Oral Langerhans cell histiocytosis.   总被引:1,自引:0,他引:1  
AIM: Our aim is to compare the different methods of treatment available for Langerhans cell histiocytosis (LCH) in the oral and maxillo-facial region. A classification based on clinical and immunohistochemical data is proposed and a grading for the severity of the disease is proposed. PATIENTS AND METHODS: Records and clinical data of 12 patients were evaluated retrospectively. The patients' ages ranged from 20 months to 47 years. Nine had manifestations in the maxillo-facial region, of which six had a single oral lesion only, with the three remaining patients having multiple lesions in this region. Three patients had lesions in the upper thorax in addition to their oral lesions. Eleven patients were treated surgically with one having been treated previously with steroid-therapy. One patient had already been treated with chemotherapy. The longest follow-up was 16 years. Immunohistochemical stains for antigen-CD-1a, antigen-S-100 and antigen-Ki-67 were performed. A proposal for staging the lesions in the oro-maxillo-facial region was made. The intensity of the antigen-Ki-67 stains was evaluated. RESULTS: Eleven patients exhibited no signs of recurrence whilst only one patient had a recurrence implying that surgical treatment was very effective in eradication and cure of the disorder. It is felt that the number of antigen-Ki-67 positive cells is related to the activity of the disease. CONCLUSION: Langerhans cell histiocytosis should be treated surgically. Only in very severe cases should surgical treatment be complemented with either radio-therapy or chemotherapy. Especially in disseminated cases, chemotherapy would appear to improve the outcome. The antigen Ki-67 as proliferation marker is suggested as a grading parameter of this disease.  相似文献   
1000.
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