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21.
The effective treatment of urethral stricture remains a medical problem. The use of proinflammatory cytokines as stimuli to improve the reparative efficacy of mesenchymal stem cells (MSCs) towards damaged tissues represents an evolving field of investigation. However, the therapeutic benefits of this strategy in the treatment of urethral stricture remain unknown. Here, we enriched exosomes derived from human umbilical cord-derived MSCs pretreated with or without tumor necrosis factor alpha (TNF-α) to evaluate their therapeutic effects in an in vivo model of TGFβ1-induced urethral stricture. Male Sprague-Dawley rats received sham (saline) or TGFβ1 injections to urethral tissues followed by incisions in the urethra. Animals in the TGFβ1 injection (urethral fibrosis) cohort were subsequently injected with vehicle control, or with exosomes derived from MSCs cultured with or without TNF-α. After 4 weeks, rats underwent ultrasound evaluation and, following euthanasia, urethral tissues were harvested for histological and molecular analysis. In vitro, the effects of MSC-derived exosomes on fibroblast secretion of collagen and cytokines were studied by enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. Exosomes derived from MSCs pretreated with TNF-α were more effective in suppressing urethral fibrosis and stricture than exosomes from untreated MSCs. We found that miR-146a, an anti-inflammatory miRNA, was strongly upregulated in TNF-α-stimulated MSCs and was selectively packaged into exosomes. Moreover, miR-146a-containing exosomes were taken up by fibroblasts and inhibited fibroblast activation and associated inflammatory responses, a finding that may underlie the therapeutic mechanism for suppression of urethral stricture. Inhibition of miR-146a in TNF-α-treated MSCs partially reduced antifibrotic effects and increased the release of proinflammatory factors of exosomes derived from these cells. Together these findings demonstrate that exosomes derived from TNF-α-treated MSCs are of therapeutic benefit in urethral fibrosis, suggesting that this strategy may have utility as an adjuvant therapy in the treatment of urethral stricture diseases.  相似文献   
22.
A cancer microenvironment generates strong hydrogen bond network system by the positive feedback loops supporting cancer complexity and robustness. Such network functions through the AKT locus generating high entropic energy supporting cancer metastatic robustness. Charged lepton particle muon follows the rule of Bragg effect during a collision with hydrogen network in cancer cells. Muon beam dismantles hydrogen bond network in cancer by the muon-catalyzed fusion, leading to apoptosis of cancer cells. Muon induces cumulative energy appearance on the hydrogen bond network in a cancer cell with its fast decay to an electron and two neutrinos. Thus, muon beam, muonic atom, muon neutrino shower, and electrons simultaneously cause fast neutralization of the AKT hydrogen bond network by the conversion of hydrogen into deuterium or helium, inactivating the hydrogen bond networks and inducing failure of cancer complexity and robustness with the disappearance of a malignant phenotype.  相似文献   
23.
Larval cuticle ofHelicoverpa (Heliothis)zea and yeast extract added to a minimal medium (MM) induced germination of conidia ofNomuraea rileyi whereas sterile distilled water or MM alone did not. Yeast extract increased mycelial yield, but when cuticle was added, mycelial yield significantly decreased. Proteases and chitinases ofN. rileyi were only expressed when cuticle was added to the MM.This article reports the results of research only. Mention of a proprietary product in this paper does not constitute a recommendation for use by US Department of Agriculture.  相似文献   
24.
Defense mechanisms againstSporothrix schenckii were studied using mouse models. After an intracutaneous injection of the yeast form ofS. schenckii to the dorsal skin of the congenitally athymic nude and normal heterozygote littermate mice, nodules were formed. They regressed and disappeared in 10 weeks in the case of normal mice. On the other hand, nodules and then ulceration developed progressively in nude mice until all animals expired by dissemination of microorganisms at the 11th week of inoculation. Histopathologically the migrated cells were similar in both the normal and the nude mice, particularly during the early phase (within 24 h), with infiltration by PMNs being predominant. Fragmentation ofS. schenckii commenced early during the 12–24 h stage of inoculation in the normal mice, while such fragmentation was scarce in nude mice even though numerous PMNs accumulated. Microscopic observations in the early stages (within 24 h of inoculation) suggested that the lack of killing activity by PMNs in nude mice contributes more to the impaired defense than the lack of macrophage activation by T-cells.  相似文献   
25.
Drought is one of the key restraints to agricultural productivity worldwide and is expected to increase further. Drought stress accompanied by reduction in precipitation pose major challenges to future food safety. Strategies should be develop to enhance drought tolerance in crops like chickpea and wheat, in order to enhance their growth and yield. Drought tolerance strategies are costly and time consuming however, recent studies specify that plant growth promoting rhizobacteria (PGPR) and plant growth regulators (PGRs) can help plants to withstand under harsh environmental condition and enable plants to cope with drought stress. PGPR can act as biofertilizer and bioenhancer for different legumes and non-legumes. The use of PGPR and symbiotic microorganisms, may be valuable in developing strategies to assist water conservation in plants. The use of PGPR has been confirmed to be an ecologically sound way of enhancing crop yields by facilitating plant growth through direct or indirect mechanism. The mechanisms of PGPR for water conservation include secretion of exopolysaccharides, biofilm formation, alternation in phytohormone content, improvement in sugar concentration, enhancing availability of micro- and macronutrients and changes in plant functional traits. Similarly, plant growth regulators (PGRs) are specially noticed in actively growing tissues under stress conditions and have been associated in the control of cell division, embryogenesis, root formation, fruit development and ripening, and reactions to biotic and abiotic stresses and upholding water conservation status in plants. Previous studies also suggest that plant metabolites interact with plant physiology under stress condition and impart drought tolerance. Metabolites like, sugars, amino acids, organic acid and polyols play a key role in drought tolerance of crop plants grown under stress condition. It is concluded from the present study that PGRs in combination with PGPR consortium can be an effective formulation to promote plant growth and maintenance of plant turgidity under drought stress. This review is a compilation of the effect of drought stress on crop plants and described interactions between PGPR/PGRs and plant development, knowledge of water conservation and stress release strategies of PGPR and PGRs and the role of plant metabolites in drought tolerance of crop plants. This review also bridges the gaps that summarizes the mechanism of action of PGPR for drought tolerance of crop plants and sustainability of agriculture and applicability of these beneficial rhizobacteria in different agro-ecosystems under drought stress.  相似文献   
26.
Background: A preponderance of evidence indicates that when treatment of hyperglycemia with insulin is provided for certain hospitalized populations, the attainment of appropriate glycemic targets improves nonglycemic outcomes such as mortality rates, morbidities (eg, wound infection, critical illness polyneuropathy, bacteremia, new renal insufficiency), duration of ventilator dependency, transfusion requirements, and length of hospital stay. Nevertheless, randomized controlled trials (RCTs) of intensive insulin therapy and studies of outcomes before and after implementation of tight glycemic control have consistently recognized an increased incidence of hypoglycemia as a complication associated with the use of lower glycemic targets and higher doses of insulin.Objectives: This commentary compares the quality of the available evidence on the clinical impact of iatrogenic hypoglycemia. We present treatment strategies designed to prevent iatrogenic hypoglycemia in the hospital setting.Methods: The PubMed database and online citations of articles tracked subsequent to publication were searched for articles on the epidemiology, clinical impact, and mechanism of harm of hypoglycemia published since 1986. In addition, we searched the literature for RCTs conducted since 2001 concerning intensive insulin therapy in the hospital critical care setting, including meta-analyses; letters to the editor were excluded. The retrieved studies were scanned and chosen selectively for full-text review based on the study size and design, novelty of findings, and evidence related to the possible clinical impact of hypoglycemia. Reference lists from the retrieved studies were searched for additional studies. Reports were summarized for the purpose of comparing and contrasting the qualitative nature of information about iatrogenic hypoglycemia in the hospital.Results: Eight RCTs of intensive glycemic management, 16 observational studies of hospitalized patients with hypoglycemia (including studies of outcomes before and after implementation of tight glycemic control), and 4 case reports on patients with hypoglycemia were selected for discussion of the incidence of hypoglycemia, significance of hypoglycemia as a marker or cause of poor prognosis, and clinical harm of hypoglycemia. Hypoglycemia was identified in clinical trials as either a category of adverse events or a complication of intensified insulin treatment. For example, a recent meta-analysis found that the incidence of severe hypoglycemia was higher among critically ill patients treated with intensive insulin therapy than among control patients, with a pooled relative risk of 6.0 (95% CI, 4.5–8.0). In the largest multisite RCT on glycemic control among patients in intensive care units (ICUs) conducted to date, deaths were reported for 27.5% (829/3010 patients) in the intensive-treatment group and 24.9% (751/3012 patients) in the conventional-treatment group (odds ratio, 1.14; 95% CI, 1.02–1.28; P = 0.02). In another multisite ICU study, although the intensive and control groups had similar mortality rates, the mortality rate was higher among hypoglycemic participants than among nonhypoglycemic participants (32.2% vs 13.6%, respectively; P < 0.01). Pooled data from 2 singlesite studies in medical and surgical ICUs revealed an increased risk of hypoglycemia in the intensive-treatment group compared with the conventional-treatment group (11.3% [154/1360] and 1.8% [25/1388], respectively; P < 0.001), but the hospital mortality rate was similar for the 2 groups (50.6% [78/154] and 52.0% [13/25], respectively). Specific sequelae of hypoglycemia affecting individual patients were described in the RCTs as well as in the observational studies. New guidelines for glycemic control have recently been issued, but results of the studies using the new targets are not yet available. We propose treatment strategies designed to prevent iatrogenic hypoglycemia in the hospital setting.Conclusions: In response to the growing evidence on the risk of hypoglycemia during intensified glycemic management of hospitalized patients, professional organizations recently revised targets for glycemic control. It is appropriate for institutions to reevaluate hospital protocols for glycemic management with intravenous insulin and, on general wards, to implement standardized order sets for use of subcutaneous insulin to achieve beneficial targets using safe strategies.  相似文献   
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Eight Danish Holstein cows were milked with a 1-mm thick specially designed soft liner on their right rear teat and a standard liner mounted under extra high tension on their left rear teat. Four of the animals were overmilked for 5 min. Rear teats were subjected to ultrasound examination on the first day and to infrared thermography on the second day. Teats were submersed in ethanol 20 min post-milking on the second day. Ultrasonography measurements showed that teat canal length increased by 30–41% during milking. Twenty minutes after milking, teats milked with modified standard liners still had elongated teat canals while teats milked with the soft liner were normalized. Overmilking tended to increase teat wall thickness. Approximately 80% of variability in teat canal length, from before teat preparation to after milking, could be explained by changes during teat preparation. Thermography indicated a general drop in teat temperature during teat preparation. Teat temperature increased during milking and continued to increase until the ethanol challenge induced a significant drop. Temperatures approached pre-challenge rather than pre-milking temperatures within 10 minutes after challenge. Teat temperatures were dependent on type of liner. Mid-teat temperatures post-challenge relative to pre-teat preparation were dependent on overmilking. Thermography and ultrasound were considered useful methods to indirectly and non invasively evaluate teat tissue integrity.  相似文献   
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30.
Adipose tissue is closely associated with angiogenesis and vascular remodeling. Chemerin is involved in inflammatory reaction and vascular dysfunction. However, the mechanisms of chemerin participating in vascular remodeling and whether Growth arrest‐specific homeobox (Gax) can effectively intervene it remain obscured. Here, 3T3‐F442A preadipocytes were cultured, injected into athymic mice to model fat pads, and treated respectively with Ad‐chemerin, Ad‐Gax, or specific inhibitors in vitro and in vivo. MTT, flow cytometry, Western blotting, and imunohisto(cyto)‐chemistry analyses showed that chemerin enhanced the expression of FABP4 and VEGF, activated Akt/mTOR and ERK pathways, increased the cell percent of S phase, decreased the percent of G0‐G1 phase and apoptotic cells, and augmented neovascular density in fat pads. Inversely, Gax suppressed the expression of these adipogenic and vasifactive markers and these signaling proteins, decreased the percent of S phase cells, and increased those of G0‐G1 phase and apoptotic cells, and reduced the neovascular density. Our results indicate that chemerin‐CMKLR1 activates Akt/mTOR and ERK pathways and facilitates preadipocyte proliferation, adipogenesis, and angiogenesis. Contrarily, Gax weakens the effect of chemerin on preadipocyte biofunctions.  相似文献   
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