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1.
The growth and development of hair follicles is influenced by a number of different growth factors and cytokines, particularly members of the fibroblast growth factor (FGF) family. Keratinocyte growth factor (KGF or FGF-7) is a recently identified 28-kd member of the FGF family that induces proliferation of a wide variety of epithelial cells, including keratinocytes within the epidermis and dermal adnexa. Because KGF induces marked proliferation of keratinocytes, and both KGF and KGF receptor (KGFR) mRNA are expressed at high levels in skin, we sought to localize KGF and KGFR in skin by in situ hybridization. KGFR mRNA was relatively strongly expressed by keratinocytes in the basilar epidermis as well as throughout developing hair follicles of rat embryos and neonates. KGF mRNA was expressed at lower levels than was KGFR but could be localized to follicular dermal papillae in rat embryos and neonates. These results prompted us to investigate the effects of KGF on hair follicles in two distinct murine models of alopecia. In the first model, recombinant KGF (rKGF) induced dose-dependent hair growth over most of the body in nu/nu athymic nude mice when administered intraperitoneally or subcutaneously over 17 to 18 days. When administered subcutaneously, rKGF induced the most extensive hair growth at the sites of injection. Histologically, rKGF induced marked follicular and sebaceous gland hypertrophy, a normalization of the nu/nu follicular keratinization defect, and an increase in follicular keratinocyte proliferation as assessed by bromodeoxyuridine labeling. In the second model, a neonatal rat model of cytosine arabinoside chemotherapy-induced alopecia in which interleukin-1, epidermal growth factor, and acidic FGF have all demonstrated some degree of alopecia cytoprotection, rKGF induced a dose-dependent cytoprotective effect, abrogating as much as 50% of the alopecia in this model when administered beginning 1 day before the onset of chemotherapy. Taken together, these data suggest that KGF is an important endogenous mediator of normal hair follicle growth, development, and differentiation.  相似文献   
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Bonnet U  Leniger T  Wiemann M 《Brain research》2000,872(1-2):116-124
Transmembrane acid extruders, such as electroneutral operating Na(+)/H(+)-exchangers (NHE) and Na(+)-dependent Cl(-)/HCO(3)(-)-exchangers (NCHE) are essential for the maintenance and regulation of cell volume and intracellular pH (pH(i)). Both of them are hypothesised to be closely linked to the control of excitability. To get further information about the relation of neuronal pH(i) and activity of cortical neurones we investigated the effect of NHE- and/or NCHE-inhibition on (i) spontaneous action potentials and epileptiform burst-activity (induced by bicuculline-methiodide, caffeine or 4-aminopyridine) and (ii) on pH(i) of CA3-neurones. NHE-inhibition by amiloride (0.25-0.5 mM) or its more potent derivative dimethylamiloride (50 microM) and NCHE-inhibition by 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS, 0.25-0.5 mM) induced a biphasic alteration of neuronal activity: an initial, up to 30 min lasting, increase in frequency of action potentials and bursts preceded a growing and partially reversible suppression of neuronal activity. In BCECF-loaded neurones the pH(i), however, continuously decreased during either amiloride- or DIDS-treatment and reached its steady-state (DeltapH(i) up to 0.3 pH-units) when the neuronal activity was markedly suppressed. Combined treatment with amiloride (0.5 mM) and DIDS (0.5 mM) or treatment with harmaline alone (0.25-0.5 mM), which also continuously acidified neurones via inhibition of an amiloride-insensitive NHE-subtype, induced a monophasic and partially reversible suppression of neuronal activity. As an initial excitatory period failed to occur during combined NHE/NCHE-inhibition we speculate that its occurrence during amiloride- or DIDS-treatment resulted rather from disturbances in volume- than in pH(i)-regulation. The powerful inhibitory and anticonvulsive properties of NHE- and NCHE-inhibitors, however, very likely based upon intracellular acidification - as derived from our previous findings that a moderate increase in intracellular free protons is sufficient to reduce membrane excitability of CA3-neurones.  相似文献   
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Journal of Neuro-Oncology - Evidence supporting routine postoperative antiepileptic drug (AED) prophylaxis following oncologic neurosurgery is limited, and actual practice patterns are largely...  相似文献   
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Background: Personal beliefs about sexual attitudes and rights likely affect reproductive health behaviors. We examined the prevalence and predictors of low sexual assertiveness (SA) among sexually active females across three age groups (14-17 yo, 18-21 yo, and 22-26 yo).Methods: 904 white, black, and Mexican-American females presenting at community-based family planning clinics in Southeast Texas between April 1997 and February 1998 completed an anonymous self-report questionnaire that assessed demographic and reproductive characteristics, dating behaviors, mental health measures and occurrence of physical and sexual assault. Subjects also completed a sexual assertiveness scale that assessed one's right to make various reproductive health decisions and sexual communications to partners. A total SA score was obtained by summing the 13 items; scores were then dichotomized so those scoring in the lowest quartile could be compared to the others. Data were analyzed using chi-square and logistic regression stratified by age group (244 aged 14-17; 392 aged 18-21; and 268 aged 22-26).Results: 27% of subjects aged 14-17, 22% aged 18-21, and 17% aged 22-26 were identified as having low SA. For 14-17 years olds, logistic regression analyses revealed that those with low SA as compared to adequate SA were significantly more likely to be Mexican American (OR = 4.8) or black (OR = 3.1) than white, to have hand /= 1 (OR = 1.8). Among 22-26 years olds, low SA was associated with gravidity >/= 1 (OR = 2.8), being a high school dropout (OR = 2.1), and inconsistent birth control use in the last 12 months (OR = 1.9).Conclusions: These data suggest that 1 in 4 sexually active women report low SA and for two age groups these attitudes are associated with inconsistent contraception. Among 18-21 years olds, low SA is also associated with forced sexual contact and depressive symptoms. Thus, efforts to prevent unintended pregnancy and unwanted sexual contact may be more effective if individual levels of SA are taken into account.  相似文献   
5.
PURPOSE: Sulthiame is a carbonic anhydrase (CA) inhibitor with an anticonvulsant effect in the treatment of benign and symptomatic focal epilepsy in children. The aim of the study was to elucidate the mode of action of sulthiame with respect to possible changes of intracellular pH (pHi) that might develop along with sulthiame's anticonvulsant properties. METHODS: The effects of sulthiame (a) on pHi of 2',7-bis(2-carboxyethyl)-5(6)-carboxyfluorescein-acetoxymetyl ester (BCECF-AM) loaded CA3 neurones as well as (b) on epileptiform activity (induced by 50 microM 4-aminopyridine) were compared with those of the CA inhibitors acetazolamide and benzolamide. RESULTS: In the majority of neurons, sulthiame (1.0-1.5 mM; n = 8) as well as the membrane permeant acetazolamide (0.5-1.0 mM; n = 6) reversibly decreased pHi by 0.18 +/- 0.05 (SD) and 0.17 +/- 0.10 (SD) pH units, respectively, within 10 min. The poor membrane permeant benzolamide (1.0-2.0 mM) had no influence on pHi (n = 8). Sulthiame (1.0-2.5 mM) and acetazolamide (1.0-2.0 mM) reversibly reduced the frequency of action potentials and epileptiform bursts after 10-15 min (n = 9, n = 7), whereas benzolamide (1.0-2.0 mM) had no effect (n = 6). CONCLUSIONS: The results suggest that sulthiame acts as a membrane-permeant CA inhibitor whose beneficial effect on epileptiform activity results at least in part from a modest intracellular acidosis of central neurons.  相似文献   
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OBJECTIVE: Heat shock protein 27 (HSP27) is produced in response to pathophysiologic stress in animal cells. The authors have previously shown that HSP27 is an independent prognostic indicator in patients with ovarian carcinoma. The present study was performed to see whether HSP27 remained an independent prognostic indicator with longer follow-up. METHODS: One hundred and three consecutive patients with epithelial ovarian carcinoma were studied. Slides were prepared from fresh tissue. HPS27 staining was performed as previously described. Patient records were examined for FIGO stage, grade, histology, level of cytoreduction and survival. RESULTS: One hundred and three patients were followed for a mean of 60 months. Twenty patients had FIGO Stage I disease, four Stage II, 59 Stage III, and 20 Stage IV. Immunohistochemical (IHC) staining for HSP27 was not related to histologic grade, level of cytoreduction or histologic subtype. A statistically significant decrease in HSP27 staining was found to correlate with increased FIGO stage (p = 0.008). Using cox-regression analysis, HSP27 staining (p = 0.025), stage (p = 0.0012), and level of cytoreduction (p < 0.0001) were independent predictors of survival in these patients. CONCLUSION: Cox-regression analysis found HSP27 to be an independent indicator of prognosis and survival in patients with ovarian carcinoma who had longer follow-up. Decreased HSP27 staining was related to decreased survival. This study confirms the authors' earlier report on the importance of HSP27 as a prognostic indicator in ovarian carcinoma.  相似文献   
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