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351.
Mesenchymoma of the chest wall in children   总被引:1,自引:0,他引:1  
Benign chest wall mesenchymoma in children is an extremely rare disease. Only 20 patients have been reported in the world literature. We report a chest wall mesenchymoma in a 2-year-old boy who was admitted to the hospital after a routine chest roentgenogram showed a mass in the right upper chest wall. The patient was asymptomatic. Clinical examination was negative, but chest roentgenograms and computed tomography showed a mass in the right upper chest wall involving the third rib. A 2 x 2 x 1.5-cm tumor was excised totally with partial resection of the third rib. The histology of the lesion corresponded to a mesenchymoma (hamartoma) of the chest wall. Our patient has been followed up for 8 years without recurrence.  相似文献   
352.
The tumor-producing activity of local applications of dithranol, 10-propionyl dithranol and butantrone was studied in 420 female white NMRI mice. An initiation with 20 micrograms of 7,12-dimethyl-benz(alpha)anthracene (DMBA) was followed 2 weeks later by three applications per week of the test compounds in 50 microliters of acetone for 50 weeks. Several control groups receiving only acetone or DMBA and test compounds without DMBA were included. Dithranol and 10-propionyl dithranol caused transient, although serious, skin irritation during the first 2 weeks of the treatment. Hyperplasia was a common finding in the same groups at the end of the treatment. Dithranol (3.5 mM) induced 11 papillomas in 8 mice (26.7%) without DMBA and 29 papillomas in 17 mice (56.7%) with DMBA. 10-Propionyl dithranol was tumorigenic as well: 3.5 mM caused 15 papillomas in 11 mice (36.6%) without DMBA and 28 papillomas in 17 mice (56.7%) with DMBA and 1.5 mM with DMBA caused 7 papillomas in 6 mice (20%). In the butantrone groups, there was only one single papilloma with the 1.5 mM concentration plus DMBA. It is concluded that, in contrast to dithranol and 10-propionyl dithranol, butantrone (3.5 mM) is not tumorigenic in the dorsal murine skin.  相似文献   
353.
BACKGROUND: The adhesion molecule CD44 standard (CD44s), and its variant isoforms v3 and v6 are associated with cell-to-cell adhesion. The down-regulation of CD44 standard and its variant isoform CD44v6 is linked with early cancer cell dissemination, but the relationship between CD44v3 and malignant features of prostate cancer (PC) has not been established previously. METHODS: The expression of CD44s and its CD44v3 and CD44v6 isoforms was analysed by immunohistochemistry in 209 archival PC biopsy specimens to establish their prognostic value. RESULTS: Down-regulation of CD44s and CD44v6 was related to high T classification, metastasis, high Gleason score, DNA aneuploidy, high S-phase fraction, high mitotic index, perineural growth and dense amount of tumour infiltrating lymphocytes (p < 0.03 for all). Down-regulation of CD44s and CD44v6 was related to poor survival in the entire cohort (p < 0.0001), in M0 tumours (p < 0.001) and in T1-2M0 tumours (p < 0.05). In needle biopsies and TURP specimens, the prognostic impact of the investigated parameters was similar. In the multivariate analysis, T classification (p = 0.0009), presence of metastases (p < 0.0001), Gleason score (p = 0.0060) and CD44v6 (p = 0.0220) expression were independent prognostic factors. In M0 tumours, T classification (p < 0.0001) and CD44v6 (p = 0.003) independently predicted survival. CONCLUSION: Down-regulation of CD44s and its CD44v6 isoform is related to tumour malignancy and unfavourable prognosis in PC.  相似文献   
354.
Excess moisture and microbial growth have been associated with adverse health effects, especially in the airways, of the inhabitants of moisture-damaged buildings. The spores of Penicillium spp. are commonly present in the indoor air, both in moisture-damaged and in reference buildings, though their numbers seem to be significantly higher in the damaged buildings. To assess the potential of Penicillium spinulosum to evoke harmful respiratory effects, mice were exposed via intratracheal instillation to a single dose of the spores of P. spinulosum, isolated from the indoor air of a moisture-damaged building (1×10(5), 1×10(6), 5×10(6), 1×10(7) or 5×10(7) spores). Inflammation and toxicity in lungs were evaluated 24 h later. The time-course of the effects was investigated with the dose of 5×10(6) spores for 28 days. The fungal spores caused mild transient inflammation. The spore exposure transiently increased proinflammatory cytokine (TNFα and IL-6) levels in bronchoalveolar lavage fluid (BALF) in a dose- and time-dependent manner. The highest concentrations of both cytokines were measured at 6 h after a single dosage. The spore exposure did not cause expression of inducible nitric oxide synthase in lavaged cells. Neutrophils were acutely recruited into airways, but the response leveled off in 3 days. Neither cytotoxicity nor major changes in vascular permeability (i.e. increases in albumin, total protein, lactate dehydrogenase or hemoglobin levels in BALF) were observed in the lungs. Considering the profile and magnitude of the changes and the dose of the spores, we conclude that P. spinulosum has a low potential to cause acute respiratory inflammation, nor does it cause direct cytotoxicity.  相似文献   
355.
Occupants in moisture-damaged buildings suffer frequently from respiratory symptoms. This may be partly due to the presence of abnormal microbial growth or the altered microbial flora in the damaged buildings. However, the specific effects of the microbes on respiratory health and the way they provoke clinical manifestations are poorly understood. In the present study, we exposed mice via intratracheal instillation to a single dose of Mycobacterium terrae isolated from the indoor air of a moisture-damaged building (1 X 10(7), 5 X 10(7), or 1 X 10(8) microbes). Inflammation and toxicity in lungs were evaluated 2 hr later. The time course of the effects was assessed with the dose of 1 X 10(8) bacterial cells for up to 28 days. M. terrae caused a sustained biphasic inflammation in mouse lungs. The characteristic features for the first phase, which lasted from 6 hr to 3 days, were elevated proinflammatory cytokine [i.e., tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6)] levels in the bronchoalveolar lavage fluid (BALF). TNF-alpha was produced in the lungs more intensively than was IL-6. Neutrophils were the most abundant cells in the airways during the first phase, although their numbers in BALF remained elevated up to 21 days. The characteristics of the second phase, which lasted from 7 to 28 days, were elevated TNF-alpha levels in BALF, expression of inducible nitric oxide synthase in BAL cells, and recruitment of mononuclear cells such as lymphocytes and macrophages into the airways. Moreover, total protein, albumin, and lactate dehydrogenase concentrations were elevated in both phases in BALF. The bacteria were detected in lungs up to 28 days. In summary, these observations indicate that M. terrae is capable of provoking a sustained, biphasic inflammation in mouse lungs and can cause a moderate degree of cytotoxicity. Thus, M. terrae can be considered a species with potential to adversely affect the health of the occupants of moisture-damaged buildings.  相似文献   
356.
PURPOSE: PALB2 is a recently identified breast cancer susceptibility gene. We have previously identified in the Finnish population a PALB2 c.1592delT founder truncation mutation that is associated with an increased risk of breast cancer. In the present study, we wanted to assess in more detail the increased risk (hazard ratio, HR) and the age-specific cumulative risk (penetrance) of c.1592delT with regard to susceptibility to breast and other forms of cancer. EXPERIMENTAL DESIGN: Modified segregation analyses fitted under maximum likelihood theory were used to estimate age-specific cumulative risks and HRs using the families of mutation carriers identified from a consecutive series of breast cancer cases unselected for age at onset or family history. RESULTS: We found a substantially increased risk of breast cancer [HR, 6.1; 95% confidence interval (95% CI), 2.2-17.2; P = 0.01] equivalent to a 40% (95% CI, 17-77) breast cancer risk by age 70 years, comparable to that for carriers of mutations in BRCA2. We found marginal evidence (P = 0.06) that the HR for breast cancer decreased with age by 4.2% per year (95% CI, 0.2-8.1), from 7.5-fold at age 30 years to 2.0-fold at age 60 years. CONCLUSIONS: Our results suggest that it may be appropriate to offer PALB2 c.1592delT mutation testing to Finnish women with breast cancer, especially those with an early age at onset or a family history of breast or related cancers, and to offer carriers the option of participation in extended disease surveillance programs.  相似文献   
357.
Insulin-like growth factors (IGF) and IGF-binding proteins (IGFBP) have been shown to be involved in ovarian follicular growth/development and steroidogenesis. Recently, a number of low-affinity IGFBP-related proteins (IGFBP-rP) have been characterized. In this study, we investigated the expression of the gene for IGFBP-rP2 (also known as connective tissue growth factor, CTGF) in human granulosa cells in vitro and in vivo. Northern blot analysis demonstrated that IGFBP-rP2 mRNA is expressed in cultured human granulosa-luteal cells obtained from women undergoing an IVF programme. Accumulation of IGFBP-rP2 mRNA was dose-dependently down-regulated by FSH and LH after 24 h treatment (both P < 0.05) in cultured granulosa-luteal cells. The inhibitory effects of gonadotrophins were mimicked by treatment with the protein kinase A activator, (Bu)(2)cAMP. Protein kinase C inhibitor staurosporine reduced, whereas protein kinase C activator TPA (12-O-tetradecanoyl phorbol 13-acetate) increased, IGFBP-rP2 mRNA accumulation. These results suggest that the inhibitory effects of gonadotrophins on IGFBP-rP2 gene expression may involve signal transduction via both protein kinase A and C pathways. Immunohistochemical analysis revealed positive staining for IGFBP-rP2 in the granulosa and theca cells of normal human ovarian follicles. Corpus luteum and ovarian surface epithelial cells were also positively stained. Modulation of IGFBP-rP2 expression by gonadotrophic hormones may have a role in ovarian follicular development and in the ovulatory process.  相似文献   
358.
3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a chlorine disinfection by-product in drinking water, causes follicular adenomas and carcinomas in thyroid glands of Wistar rats with an unknown mechanism. We evaluated effects of MX on blood thyroid stimulating hormone (TSH), thyroxine (T4), triiodothyronine (T3), prolactin (PRL) and growth hormone (GH) levels in male and female Wistar rats to assess their role in the tumorigenesis. The levels of TSH, PRL and GH in serum of male rats were not significantly affected by a single dose of 1, 10 or 60 mg/kg of MX administered by gavage 2 h before sampling. In repeated dose experiments MX was administered at dose levels of 1, 10 or 60 mg/kg of MX (40 mg/kg for females) in water by gavage daily for 1 or 3 weeks. Thyroid glands, adrenal glands and the liver were evaluated for morphological changes and cell proliferation activity after staining with proliferating cell nuclear antigen (PCNA). The dose of 60 mg/kg MX was toxic upon repeated administration. Nevertheless, MX did not affect blood TSH and T4 levels at any time point in either sex. T3 concentration increased transiently in males (by 37% after week 1) at the highest MX dose but not in females. MX did not change the weights of thyroid glands, their morphology and cell proliferation activity by the end of the week 3. MX did not affect blood PRL levels but decreased GH levels in males at all doses after the first week of MX treatment. The results indicate that MX does not alter blood TSH and thyroid hormone levels in rats, and imply that MX may not cause thyroid follicular cell tumors by TSH-mediated hormonal promotion.  相似文献   
359.
360.
AIMS: To study the expression of versican, a large proteoglycan involved in repressing adhesion between cells and the extracellular matrix in pharyngeal squamous cell carcinoma (PSCC), and its relation to the expression of p53 and catenins, histological differentiation, clinical data, and prognosis. METHODS: For the retrospective survey, primary tumours for analyses were obtained from 118 patients diagnosed with PSCC of the oropharynx or hypopharynx. The immunohistochemical expression of versican was studied and was related to the expression pattern of p53 and catenins, in addition to clinical data and survival. RESULTS: In the primary tumours, strong stromal versican expression was graded as low in 59 (50%) and high in 59 (50%) cases. In addition, intracellular versican staining was seen in nine (8%) tumours. In local lymph node metastases, strong stromal versican staining was significantly more frequent compared with the primary tumours (p = 0.018). Strong stromal versican staining was more frequently seen in less advanced tumours (p = 0.015). There was no association between versican expression and the other investigated variables (p53, catenins, TNM status, and histological grade). Neither stromal nor intracellular versican expression predicted overall survival in these patients. CONCLUSIONS: Versican was more strongly expressed in the stroma of local metastases and in the earlier stages of disease in PSCC. However, versican expression was not an independent prognostic factor in this entity.  相似文献   
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