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We have previously demonstrated that nestin-expressing hair follicle-associated-pluripotent (HAP) stem cells are located in the bulge area. HAP stem cells have been previously shown to differentiate to neurons, glial cells, keratinocytes, smooth-muscle cells, melanocytes and cardiac-muscle cells in vitro. Subsequently, we demonstrated that HAP stem cells could effect nerve and spinal cord regeneration in mouse models, differentiating to Schwann cells and neurons. In previous studies, we established an efficient protocol for the differentiation of cardiac-muscle cells from mouse HAP stem cells. In the present study, we isolated the upper part of human hair follicles containing human HAP (hHAP) stem cells. The upper parts of human hair follicles were suspended in DMEM containing 10% FBS where they differentiated to cardiac-muscle cells as well as neurons, glial cells, keratinocytes and smooth-muscle cells. This method is appropriate for future use with human hair follicles to produce hHAP stem cells in sufficient quantities for future heart, nerve and spinal cord regeneration in the clinic.  相似文献   
73.
BackgroundFever with jaundice is a common symptom of some infectious diseases. In public health surveillance within the Democratic Republic of the Congo (DRC), yellow fever is the only recognized cause of fever with jaundice. However, only 5% of the surveillance cases are positive for yellow fever and thus indicate the involvement of other pathogens. Leptospira spp. are the causative agents of leptospirosis, a widespread bacterial zoonosis, a known cause of fever with jaundice. This study aimed to determine the seropositivity of anti-Leptospira antibodies among suspected yellow fever cases and map the geographical distribution of possible leptospirosis in the DRC.MethodsWe conducted a retrospective study using 1,300 samples from yellow fever surveillance in the DRC from January 2017 to December 2018. Serum samples were screened for the presence of IgM against Leptospira spp. by a whole cell-based IgM ELISA (Patoc-IgM ELISA) at the Institut National de Recherche Biomedicale in Kinshasa (INRB) according to World Health Organization (WHO) guidance. Exploratory univariable and multivariable logistic regression analyses were undertaken to assess associations between socio-demographic factors and the presence of Leptospira IgM.ResultsOf the 1,300 serum samples screened, 88 (7%) showed evidence of IgM against Leptospira spp. Most positive cases (34%) were young adult males in the 20–29-year group. There were statistically significant associations between having Leptospira IgM antibodies, age, sex, and living area. Observed positive cases were mostly located in urban settings, and the majority lived in the province of Kinshasa. There was a statistically significant association between seasonality and IgM Leptospira spp. positivity amongst those living in Kinshasa, where most of the positive cases occurred during the rainy season.ConclusionsThis study showed that leptospirosis is likely an overlooked cause of unexplained cases of fever with jaundice in the DRC and highlights the need to consider leptospirosis in the differential diagnosis of fever with jaundice, particularly in young adult males. Further studies are needed to identify animal reservoirs, associated risk factors, and the burden of human leptospirosis in the DRC.  相似文献   
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We report herein the SAR studies of a series of indole- and indolizine-glyoxylamides that demonstrate substantial in vitro anti-proliferative activities against cancer cell lines, including multidrug resistance (MDR) phenotypes. The in vitro cytotoxic effects have been demonstrated across a wide array of tumor types of various origins (e.g., breast, colon, uterine).  相似文献   
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AIMS: Effective household hygiene measures require that sources of bacterial contamination and the places to which contamination spreads be carefully identified. Therefore, a study was performed to examine the distribution of microorganisms throughout ordinary households in Japan, which has its own unique customs of daily life and food preparation. METHODS AND RESULTS: Using the stamping method, samples were taken from 100 different places and items in each of 86 households. This study found kitchens/dining rooms to have the greatest level of microbial contamination and bathrooms, the next highest level. Toilets (water closets) were found to have an unexpectedly low level of bacterial contamination. The largest bacterial counts were found on items such as drain traps, dish-washing sponges, counter towels, sinks, dish-washing tubs, and bathroom sponges. CONCLUSIONS: It is necessary to carefully identify both the items that can become instruments for spreading bacterial contamination and the places that easily become subject to secondary contamination, and then to take timely and effective disinfection/sanitizing measures. SIGNIFICANCE AND IMPACT OF THE STUDY: The data gathered in this study will be very valuable for anticipating the pathways over which bacteria are transported and prioritizing disinfection targets, to make effective disinfection possible.  相似文献   
76.
Neotyphodium endophytes are vertically transmitted fungal symbionts of grasses. Being pest-repelling and growth-promoting agents for their hosts, and also potential mycotoxin producers, their detection in plants is important. Observation of chemically cleared flowers of infected grasses (Festuca arundinacea, F. pratensis, Lolium perenne, and L. multiflorum) using differential interference contrast microscopy revealed the existence of endophytes within immature ovaries of host plants. This observation method provides an accurate and easy way to detect and distinguish Neotyphodium endophytes in flowering host grasses and to investigate the seed transmission process, which is critical to their life cycle, and the practical use of infected plants.  相似文献   
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CD4+ T cells, particularly Th2 cells, play a pivotal role in allergic airway inflammation. However, the requirements for interactions between CD4+ and CD8+ T cells in airway allergic inflammation have not been delineated. Sensitized and challenged OT-1 mice in which CD8+ T cells expressing the transgene for the OVA(257-264) peptide (SIINFEKL) failed to develop airway hyperresponsiveness (AHR), airway eosinophilia, Th2 cytokine elevation, or goblet cell metaplasia. OT-1 mice that received naive CD4+IL-4+ T cells but not CD4+IL-4- T cells before sensitization developed all of these responses to the same degree as wild-type mice. Moreover, recipients of CD4+IL-4+ T cells developed significant increases in the number of CD8+IL-13+ T cells in the lung, whereas sensitized OT-1 mice that received primed CD4+ T cells just before challenge failed to develop these responses. Sensitized CD8-deficient mice that received CD8+ T cells from OT-1 mice that received naive CD4+ T cells before sensitization increased AHR and eosinophil numbers in bronchoalveolar lavage fluid when challenged with allergen. In contrast, sensitized CD8-deficient mice receiving CD8+ T cells from OT-1 mice without CD4+ T cells developed reduced AHR and eosinophil numbers in bronchoalveolar lavage fluid when challenged. These data suggest that interactions between CD4+ and CD8+ T cells, in part through IL-4 during the sensitization phase, are essential to the development of CD8+IL-13+ T cell-dependent AHR and airway allergic inflammation.  相似文献   
78.
SIRT1, a class III histone deacetylase, is considered a key regulator of cell survival and apoptosis through its interaction with nuclear proteins. In this study, we have examined the likelihood and role of the interaction between SIRT1 and Smad7, which mediates transforming growth factor beta (TGFbeta)-induced apoptosis in renal glomerular mesangial cells. Immunoprecipitation analysis revealed that SIRT1 directly interacts with the N terminus of Smad7. Furthermore, SIRT1 reversed acetyl-transferase (p300)-mediated acetylation of two lysine residues (Lys-64 and -70) on Smad7. In mesangial cells, the Smad7 expression level was reduced by SIRT1 overexpression and increased by SIRT1 knockdown. SIRT1-mediated deacetylation of Smad7 enhanced Smad ubiquitination regulatory factor 1 (Smurf1)-mediated ubiquitin proteasome degradation, which contributed to the low expression of Smad7 in SIRT1-overexpressing mesangial cells. Stimulation by TGFbeta or overexpression of Smad7 induced mesangial cell apoptosis, as assessed by morphological apoptotic changes (nuclear condensation) and biological apoptotic markers (cleavages of caspase3 and poly(ADP-ribose) polymerase). However, TGFbeta failed to induce apoptosis in Smad7 knockdown mesangial cells, indicating that Smad7 mainly mediates TGFbeta-induced apoptosis of mesangial cells. Finally, SIRT1 overexpression attenuated both Smad7- and TGFbeta-induced mesangial cell apoptosis, whereas SIRT1 knockdown enhanced this apoptosis. We have concluded that Smad7 is a new target molecule for SIRT1 and SIRT1 attenuates TGFbeta-induced mesangial cell apoptosis through acceleration of Smad7 degradation. Our results suggest that up-regulation of SIRT1 deacetylase activity is a potentially useful therapeutic strategy for prevention of TGFbeta-related kidney disease through its effect on cell survival.  相似文献   
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