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991.
992.
Alex C. Birdsill Cynthia M. Carlsson Auriel A. Willette Ozioma C. Okonkwo Sterling C. Johnson Guofan Xu Jennifer M. Oh Catherine L. Gallagher Rebecca L. Koscik Erin M. Jonaitis Bruce P. Hermann Asenath LaRue Howard A. Rowley Sanjay Asthana Mark A. Sager Barbara B. Bendlin 《Obesity (Silver Spring, Md.)》2013,21(7):1313-1320
993.
Marlene Thielecke Vaomalala Raharimanga Christophe Rogier Manuela Stauss-Grabo Vincent Richard Hermann Feldmeier 《PLoS neglected tropical diseases》2013,7(9)
Background
Tungiasis, a parasitic skin disease caused by the female sand flea Tunga penetrans, is a prevalent condition in impoverished communities in the tropics. In this setting, the ectoparasitosis is associated with important morbidity. It causes disfigurement and mutilation of the feet. Feasible and effective treatment is not available. So far prevention is the only means to control tungiasis-associated morbidity.Methodology
In two villages in Central Madagascar, we assessed the efficacy of the availability of closed shoes and the twice-daily application of a plant-based repellent active against sand fleas (Zanzarin) in comparison to a control group without intervention. The study population was randomized into three groups: shoe group, repellent group and control group and monitored for ten weeks. The intensity of infestation, the attack rate and the severity of tungiasis-associated morbidity were assessed every two weeks.Findings
In the repellent group, the median attack rate became zero already after two weeks. The intensity of the infestation decreased constantly during the observation period and tungiasis-associated morbidity was lowered to an insignificant level. In the shoe group, only a marginal decrease in the intensity of infestation and in the attack rate was observed. At week 10, the intensity of infestation, the attack rate and the severity score for acute tungiasis remained significantly higher in the shoe group than in the repellent group. Per protocol analysis showed that the protective effect of shoes was closely related to the regularity with which shoes were worn.Conclusions
Although shoes were requested by the villagers and wearing shoes was encouraged by the investigators at the beginning of the study, the availability of shoes only marginally influenced the attack rate of female sand fleas. The twice-daily application of a plant-based repellent active against sand fleas reduced the attack to zero and lowered tungiasis-associated morbidity to an insignificant level. 相似文献994.
Michael Pohlscheidt Melanie Jacobs Stefan Wolf Joerg Thiele Alexander Jockwer Josef Gabelsberger Marco Jenzsch Hermann Tebbe Josef Burg 《Biotechnology progress》2013,29(1):222-229
Increasing capacity utilization and lowering manufacturing costs are critical for pharmaceutical companies to improve their competitiveness in a challenging environment. Development of next generation cell lines, improved media formulations, application of mature technologies and innovative operational strategies have been deployed to improve yields and capacity utilization. This article describes a large‐scale perfusion strategy for the N‐1 seed train bioreactor that was successfully applied to achieve higher inoculation cell densities in the production culture. The N‐1 perfusion at 3,000‐L scale, utilizing a inclined settler, achieved cell densities of up to 158 × 105 cell mL?1 at perfusion rates of 2950 L day?1 and a retention efficiency of >85%. This approach increased inoculation cell densities and decreased cultivation times by ~20% in a CHO‐based, fed‐batch antibody manufacturing process while providing comparable culture performance, productivity, and product quality. The strategy therefore yielded significant increase in capacity utilization and concomitant cost improvement in a large scale cGMP facility. Details of the strategy, the cell retention device, and the cell culture performance are described in this article. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013 相似文献
995.
Stefan Listl Lina Jansen Albrecht Stenzinger Kolja Freier Katharina Emrich Bernd Holleczek Alexander Katalinic Adam Gondos Hermann Brenner the GEKID Cancer Survival Working Group 《PloS one》2013,8(1)
The purpose of the present study was to describe the survival of patients diagnosed with oral cavity cancer in Germany. The analyses relied on data from eleven population-based cancer registries in Germany covering a population of 33 million inhabitants. Patients with a diagnosis of oral cavity cancer (ICD-10: C00-06) between 1997 and 2006 are included. Period analysis for 2002–2006 was applied to estimate five-year age-standardized relative survival, taking into account patients'' sex as well as grade and tumor stage. Overall five-year relative survival for oral cavity cancer patients was 54.6%. According to tumor localization, five-year survival was 86.5% for lip cancer, 48.1% for tongue cancer and 51.7% for other regions of the oral cavity. Differences in survival were identified with respect to age, sex, tumor grade and stage. The present study is the first to provide a comprehensive overview on survival of oral cavity cancer patients in Germany. 相似文献
996.
Daniel Heinrichs Marie-Luise Berres Andreas Nellen Petra Fischer David Scholten Christian Trautwein Hermann E. Wasmuth Hacer Sahin 《PloS one》2013,8(6)
Liver fibrosis is associated with infiltrating immune cells and activation of hepatic stellate cells. We here aimed to investigate the effects of the CC chemokine CCL3, also known as macrophage inflammatory protein-1α, in two different fibrosis models. To this end, we treated mice either with carbon tetrachloride or with a methionine- and choline-deficient diet to induce fibrosis in CCL3 deficient and wild-type mice. The results show that the protein expression of CCL3 is increased in wild-type mice after chronic liver injury. Deletion of CCL3 exhibited reduced liver fibrosis compared to their wild-type counterparts. We could validate these results by treating the two mouse groups with either carbon tetrachloride or by feeding a methionine- and choline-deficient diet. In these models, lack of CCL3 is functionally associated with reduced stellate cell activation and liver immune cell infiltration. In vitro, we show that CCL3 leads to increased proliferation and migration of hepatic stellate cells. In conclusion, our results define the chemokine CCL3 as a mediator of experimental liver fibrosis. Thus, therapeutic modulation of CCL3 might be a promising target for chronic liver diseases. 相似文献
997.
Population-based survival studies of breast cancer patients are commonly restricted to age- and stage-specific analyses. This study from Germany aimed at extending available population-based survival data on further prognostic cancer characteristics such as tumor grade, hormone receptor status and human epidermal growth factor receptor type 2 (HER2/neu) expression. Data from the population-based Saarland Cancer Registry including female patients diagnosed with invasive breast cancer between 2000 and 2009 were included. Period analysis methodology and regression modelling were used to obtain estimates of 5-year relative survival and tumor related excess risks in 2005-2009. Overall age standardized 5-year relative survival was 83%. In addition to age and stage, tumor grade and hormone receptor status were independent predictors of 5-year relative survival. Detailed analyses by age, stage, morphology, tumor grade, hormone receptor status and HER2/neu expression consistently revealed lower survival of patients with high grade, hormone receptor negative or HER2/neu positive cancers and patients aged 70 years or older. This high resolution study extends available population-based survival data of breast cancer patients. Particular efforts should be made to overcome the persisting large survival deficits, which were observed for elderly patients in all clinical subgroups. 相似文献
998.
Henri A. Thomassen Trevon Fuller Salvi Asefi-Najafabady Julia A. G. Shiplacoff Prime M. Mulembakani Seth Blumberg Sara C. Johnston Neville K. Kisalu Timothée L. Kinkela Joseph N. Fair Nathan D. Wolfe Robert L. Shongo Matthew LeBreton Hermann Meyer Linda L. Wright Jean-Jacques Muyembe Wolfgang Buermann Emile Okitolonda Lisa E. Hensley James O. Lloyd-Smith Thomas B. Smith Anne W. Rimoin 《PloS one》2013,8(7)
Climate change is predicted to result in changes in the geographic ranges and local prevalence of infectious diseases, either through direct effects on the pathogen, or indirectly through range shifts in vector and reservoir species. To better understand the occurrence of monkeypox virus (MPXV), an emerging Orthopoxvirus in humans, under contemporary and future climate conditions, we used ecological niche modeling techniques in conjunction with climate and remote-sensing variables. We first created spatially explicit probability distributions of its candidate reservoir species in Africa''s Congo Basin. Reservoir species distributions were subsequently used to model current and projected future distributions of human monkeypox (MPX). Results indicate that forest clearing and climate are significant driving factors of the transmission of MPX from wildlife to humans under current climate conditions. Models under contemporary climate conditions performed well, as indicated by high values for the area under the receiver operator curve (AUC), and tests on spatially randomly and non-randomly omitted test data. Future projections were made on IPCC 4th Assessment climate change scenarios for 2050 and 2080, ranging from more conservative to more aggressive, and representing the potential variation within which range shifts can be expected to occur. Future projections showed range shifts into regions where MPX has not been recorded previously. Increased suitability for MPX was predicted in eastern Democratic Republic of Congo. Models developed here are useful for identifying areas where environmental conditions may become more suitable for human MPX; targeting candidate reservoir species for future screening efforts; and prioritizing regions for future MPX surveillance efforts. 相似文献
999.
In repeated visual search tasks, facilitation of reaction times (RTs) due to repetition of the spatial arrangement of items occurs independently of RT facilitation due to improvements in general task performance. Whereas the latter represents typical procedural learning, the former is a kind of implicit memory that depends on the medial temporal lobe (MTL) memory system and is impaired in patients with amnesia. A third type of memory that develops during visual search is the observers’ explicit knowledge of repeated displays. Here, we used a visual search task to investigate whether procedural memory, implicit contextual cueing, and explicit knowledge of repeated configurations, which all arise independently from the same set of stimuli, are influenced by sleep. Observers participated in two experimental sessions, separated by either a nap or a controlled rest period. In each of the two sessions, they performed a visual search task in combination with an explicit recognition task. We found that (1) across sessions, MTL-independent procedural learning was more pronounced for the nap than rest group. This confirms earlier findings, albeit from different motor and perceptual tasks, showing that procedural memory can benefit from sleep. (2) Likewise, the sleep group compared with the rest group showed enhanced context-dependent configural learning in the second session. This is a novel finding, indicating that the MTL-dependent, implicit memory underlying contextual cueing is also sleep-dependent. (3) By contrast, sleep and wake groups displayed equivalent improvements in explicit recognition memory in the second session. Overall, the current study shows that sleep affects MTL-dependent as well as MTL-independent memory, but it affects different, albeit simultaneously acquired, forms of MTL-dependent memory differentially. 相似文献
1000.
Bangwei Luo Man Jiang Xiaofeng Yang Zhiyuan Zhang Jian Xiong Hermann J. Schluesener Zhiren Zhang Yuzhang Wu 《生物化学与生物物理学报:疾病的分子基础》2013,1832(8):1260-1270
Experimental autoimmune neuritis (EAN), an autoantigen-specific T-cell-mediated disease model for human demyelinating inflammatory disease of the peripheral nervous system, is characterized by self-limitation. Here we investigated the regulation and contribution of erythropoietin (EPO) in EAN self-limitation. In EAN sciatic nerves, hypoxia, and protein and mRNA levels of hypoxia-inducible factor 1α (HIF-1α), HIF-2α, EPO and EPO receptor (EPOR) were induced in parallel at disease peak phase but reduced at recovery periods. Further, the deactivation of HIF reduced EAN-induced EPO/EPOR upregulation in EAN, suggesting the central contribution of HIF to EPO/EPOR induction. The deactivation of EPOR signalling exacerbated EAN progression, implying that endogenous EPO contributed to EAN recovery. Exogenous EPO treatment greatly improved EAN recovery. In addition, EPO was shown to promote Schwann cell survival and myelin production. In EAN, EPO treatment inhibited lymphocyte proliferation and altered helper T cell differentiation by inducing increase of Foxp3+/CD4+ regulatory T cells and decrease of IFN-γ+/CD4+ Th1 cells. Furthermore, EPO inhibited inflammatory macrophage activation and promoted its phagocytic activity. In summary, our data demonstrated that EPO was induced in EAN by HIF and contributed to EAN recovery, and endogenous and exogenous EPO could effectively suppress EAN by attenuating inflammation and exerting direct cell protection, indicating that EPO contributes to the self-recovery of EAN and could be a potent candidate for treatment of autoimmune neuropathies. 相似文献