The thioredoxin system containing thioredoxin (Trx) and thioredoxin reductase (TrxR) has profound effects on cell proliferation and protection against exogenous oxidants. The significance of the Trx system in human lung and lung diseases is, however, largely unresolved. Altogether, 66 specimens of human lung were investigated by immunohistochemistry for their expression of Trx and TrxR. The diseases included interstitial pneumonias such as usual interstitial pneumonia (UIP), desquamative interstitial pneumonia (DIP), and UIP associated with collagen vascular diseases (CVD-ILD), and granulomatous diseases such as sarcoidosis and allergic alveolitis. The ultrastructural localization of Trx and TrxR was analysed by immunoelectron microscopy. In healthy lung, Trx and TrxR were expressed in bronchial epithelium and alveolar macrophages. Trx and TrxR were highly concentrated in areas of metaplastic epithelium in UIP and in alveolar macrophages in DIP, though fibrotic areas in UIP were mainly negative. The expression of both enzymes was clearly weaker in CVD-ILD than in UIP. Granulomas of sarcoidosis showed moderate to intense Trx immunoreactivity. Ultrastructurally, Trx and TrxR were expressed diffusely in the cytosolic compartment and plasma membrane of metaplastic type II pneumocytes, macrophages, and bronchial epithelial cells. This study highlights the importance of Trx and TrxR in primary defence in bronchial epithelium, alveolar epithelium, and macrophages in human lung, but also indicates that elevated expression of these proteins may serve as markers of ongoing cell regeneration and inflammation. 相似文献
The in vitro behavior of three bioactive glasses with seven particle size distributions was studied by measuring the in situ pH inside the particle beds for 48h in simulated body fluid (SBF). After immersion, the surface of the particles was characterized with a field emission scanning electron microscope equipped with an energy-dispersive X-ray analyzer. In addition, the results were compared with the reactions of the same glasses formed as plates. A similar trend in pH as a function of immersion time was observed for all systems. However, the pH inside the particle beds was markedly higher than that in the bulk SBF of the plates. The pH decreased as power functions with increasing particle size, i.e. with decreasing surface area. The in vitro reactivity expressed as layer formation strongly depended on the particle size and glass composition. The average thickness of the total reaction layer decreased with the increase in sample surface area. Well-developed silica and calcium phosphate layers typically observed on glass plates could be detected only on some particles freely exposed to the solution. No distinct reaction layers were observed on the finest particles, possibly because the layers spread out on the large surface area. Differences in the properties of the bulk SBF and the solution inside the particle bed were negligible for particles larger than 800mum. The results enhance our understanding of the in vitro reactions of bioactive glasses in various product forms and sizes. 相似文献
Hydrogels (hylans) based on cross-linked hyaluronan (HA) are potentially good biomaterials for vascular tissue engineering applications because they are highly non-antigenic and -immunogenic. To facilitate surface endothelialization, vital to vascular deployment, we irradiated the gel surface with low wavelength UV light. This process micro-textures the smooth gel surface to provide sites for cell anchorage and causes limited scission of native long-chain HA yielding smaller fragments that elicit an enhanced cell response. In the current in vitro study, we assessed the effects of UV irradiation on the short-term (<45 min) interaction between hylan gels and human blood cells (RBCs, platelets) and coagulation proteins at physiologic temperature. Although the lowered hydrophilicity of irradiated (UV) hylans elicited greater vascular cell response relative to unmodified (U) hylans, platelet deposition was unaffected and much lower compared to collagen-coated glass controls. The adhered platelets were rounded or mildly pseudopodic and did not express p-selectin, an activation marker. Both gel types induced identical, and minimal platelet release as measured using an platelet factor 4 ELISA, and identically deferred the intrinsic and extrinsic coagulation pathways. Both gel types induced elevated levels of contact activation of bound, but not plasma-phase factor XII relative to controls. Hemolysis rates were also identical and within accepted standards. We conclude that UV-treatment of hylans, useful to improve surface endothelialization, does not compromise their short-term hemocompatibility, vital to their use as vascular implant materials. 相似文献
Over half of males experience fertility impairment after childhood cancer therapy, which often causes psychosocial distress. Yet, fertility preservation (FP) remains underutilized. The goals of this study were to determine the feasibility and impact of implementing a family-centered FP values clarification tool on sperm banking attempts among adolescent males newly diagnosed with cancer, and identify key determinants of banking attempts.
Methods
A prospective pilot study was conducted among families of males (12–25 years old), prior to cancer therapy. Thirty-nine of 41 families agreed to participate (95%); 98 participants (32 adolescents, 37 mothers, 29 fathers) completed the Family-centered Adolescent Sperm banking values clarification Tool (FAST). Analyses assessed the impact of the FAST on banking attempts and examined associations between demographic/medical characteristics, FAST subscales (perceived threat, benefits, barriers), and banking attempts.
Results
Twenty-three (59%) adolescents attempted to bank, compared to 8 adolescents (33%) during baseline assessment (p=.04). Significant associations were identified between banking attempts and adolescents’ report of perceived threat (rpb=.45, p=.01) and benefits (rpb=.57, p=.01). Only mothers’ proxy reports of adolescent perceived threat (rpb=.42, p=.01) and benefits (rpb=.47, p=.003) were associated with banking attempts, while fathers’ self-reported perceived benefits (rpb=.43, p=.03), self-reported barriers (rpb=.49, p=.01), and proxy reports of adolescent perceived threat (rpb=.38, p=.04) and benefits (rpb=.59, p=.02) were associated with banking attempts.
Conclusion
Adolescent sperm banking attempt rates significantly increased after implementation of a family-centered FP values clarification tool prior to cancer treatment. Findings underscore the importance of targeting both adolescents and their parents, particularly fathers, in FP efforts.
In Western countries, tobacco use is most prevalent among adolescents in lower socioeconomic groups. The association between socioeconomic status (SES) and tobacco use among adolescents in developing countries is unexplored. Using multiple SES measures, we investigated this association among adolescents in Ghana. 相似文献
We studied histological samples and clinical data from 111 breast carcinoma patients originally treated in 1975-1977 who did not have distant metastases at the time of diagnosis. A multivariate survival analysis using the Cox model selected the studied variables in the following order according to their prognostic association (breast cancer deaths, or deaths from any cause): axillary lymph node status, tumor size, mitotic index, and DNA ploidy status. The association of the different variables to the prognosis in respect to breast cancer deaths was evaluated 1-10 years after treatment by stepwise logistic regression. Lymph node status, tumor size, mitotic index, and DNA ploidy all showed significant relation to the prognosis but this association varied considerably with time of observation. 相似文献