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31.
32.
Natesan S Zhang G Baer DG Walters TJ Christy RJ Suggs LJ 《Tissue engineering. Part A》2011,17(7-8):941-953
This work describes the differentiation of adipose-derived mesenchymal stem cells (ASC) in a composite hydrogel for use as a vascularized dermal matrix. Our intent is that such a construct could be utilized following large-surface-area burn wounds that require extensive skin grafting and that are limited by the availability of uninjured sites. To develop engineered skin replacement constructs, we are pursuing the use of ASC. We have established that a PEGylated fibrin gel can provide a suitable environment for the proliferation of ASC over a 7 day time course. Further, we have demonstrated that PEGylated fibrin can be used to control ASC differentiation toward vascular cell types, including cells characteristic of both endothelial cells and pericytes. Gene expression analysis revealed strong upregulation of endothelial markers, CD31, and von Willebrand factor, up to day 11 in culture with corresponding evidence of protein expression demonstrated by immunocytochemical staining. ASC were not only shown to express endothelial cell phenotype, but a subset of the ASC expressed pericyte markers. The NG2 gene was upregulated over 11 days with corresponding evidence for the cell surface marker. Platelet-derived growth factor receptor beta gene expression decreased as the multipotent ASC differentiated up to day 7. Increased receptor expression at day 11 was likely due to the enhanced pericyte gene expression profile, including increased NG2 expression. We have also demonstrated that when cells are loaded onto chitosan microspheres and sandwiched between the PEGylated fibrin gel and a type I collagen gel, the cells can migrate and proliferate within the two different gel types. The matrix composition dictates the lineage specification and is not driven by soluble factors. Utilizing an insoluble bilayer matrix to direct ASC differentiation will allow for the development of both vasculature as well as dermal connective tissue from a single population of ASC. This work underscores the importance of the extracellular matrix in controlling stem cell phenotype. It is our goal to develop layered composites as wound dressings or vascularized dermal equivalents that are not limited by nutrient diffusion. 相似文献
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34.
Lakshmi TS Shanmugasundaram N Shanmuganathan S Babu M 《Journal of biomedical materials research. Part B, Applied biomaterials》2011,97(2):215-223
During skin repair, leukocyte infiltration is the principal inflammatory response which is instrumental in triggering growth factor and cytokine signals that orchestrate together to recruit cells necessary for healing. In severe wounds like burn, when acute inflammation becomes chronic, intervention is required to control inflammation so as to hasten the process of healing. Heparin, a known anticoagulant also possesses anti-inflammatory activity by its ability to interfere with the adhesion of leukocytes to the endothelium. Desulfated heparins (DSH) have subdued anticoagulant activity while possessing increased anti-inflammatory activity. Among which 2,3 DSH is found to have marked potency as an anti-inflammatory agent and has been utilized for this study. In this investigation, a controlled delivery system was designed by incorporating 2,3 DSH in microspheres and embedding in collagen matrix which could serve as a wound dressing in burns. In vivo evaluation of healing process was ascertained in rat burn wound model by qualitative and quantitative estimation of proinflammatory cytokines in serum and granulation tissue and collagen turnover was also assessed as healing progressed. The results of this study suggests that 2,3 DSH could be delivered in a controlled manner to regulate inflammatory events to hasten healing of burn wounds. 相似文献
35.
Antipsychotic drugs are widely used in the treatment of schizophrenia. While their effects are considered to be due to a modulation of dopaminergic and serotonergic signaling, little is known about their effects on noradrenergic (NA) activity in the brain. In this study, rats received either a 6 d or 14 d treatment with haloperidol using osmotic minipumps. Noradrenaline responses to novelty, appetitive food and to an aversive tail pinch were measured in the prefrontal cortex, nucleus accumbens and caudate putamen (CPu) using in vivo microdialysis. Haloperidol significantly decreased baseline NA levels after short and long term treatment. A tail pinch significantly increased NA activity in the CPu. This effect was attenuated by haloperidol in a treatment duration-dependent way. This study suggests that haloperidol modulates NA baseline activity and reduces NA responses to mildly aversive stimuli depending on treatment duration. 相似文献
36.
Nagappan A Karunanithi N Sentrayaperumal S Park KI Park HS Lee do H Kang SR Kim JA Senthil K Natesan S Muthurajan R Kim GS 《The American journal of Chinese medicine》2012,40(1):203-218
Ginsenosides and withanolides are the secondary metabolites from Panax ginseng and Withania somnifera, respectively. These compounds have similar biological properties. Two-dimensional electrophoresis (2-DE) analysis was utilized to reveal the protein profile in the roots of both plants, with the aim of clarifying similarly- and differentially-expressed proteins. Total proteins of Korea ginseng (P. ginseng) and Indian ginseng (W. somnifera) roots were separated by 2-DE using a pH 4-7 immobilized pH gradient strip in the first dimension and 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis in the second dimension. The protein spots were visualized by silver staining. Twenty-one P. ginseng proteins and 35 W. somnifera proteins were chosen for identification by matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry; of these, functions were ascribed to 14 and 22 of the P. ginseng and W. somnifera proteins, respectively. Functions mainly included general cell metabolism, defense and secondary metabolism. ATPase and alcohol dehydrogenase proteins were expressed in both plants. The results of this study, to our knowledge, are the first to provide a reference 2-DE map for the W. somnifera root proteome, and will aid in the understanding of the expression and functions of proteins in the roots of Korean ginseng and Indian ginseng. 相似文献
37.
Akhila Sai Guttikonda Chintaginjala Aruna D V S B Ramamurthy K Sridevi Senthil Kumar L Alagappan 《Indian journal of dermatology》2016,61(6):628-633
Background:Alopecia areata (AA) is a common, chronic inflammatory disease characterized by nonscarring hair loss on the scalp or any hair-bearing area of the body. Recently, dermoscopy, a noninvasive diagnostic procedure, has been employed for the diagnosis of AA.Aim:To evaluate various dermoscopic patterns in AA and correlate these patterns with the disease activity and severity.Results:A total of fifty patients of AA were recruited in the study. Female outnumbered males with the ratio being 1.173:1. Mean age of the patients was 25.06 years. Mean duration of disease was 14 months. The most common site involved was scalp (80%) and type noted was patchy (84%). Various dermoscopic patterns noted were yellow dots (YD) (88%), short vellus hair (66%), black dots (BD) (58%), broken hairs (BHs) (56%), tapering hair (TH) (26%), Coudability hairs (14%), pigtail hair (14%), and Pohl-Pinkus constrictions (2%). Statistically significant correlation was observed between BD, BHs, THs, and disease activity. No significant correlation was found between severity and any of the dermoscopic features.Conclusion:The most common dermoscopic pattern in our study was YD. Presence of BDs, BHs, and THs indicate active disease. Dermoscopic patterns were not affected by severity of the disease. 相似文献
38.
Vasdev N Natesan S Galineau L Garcia A Stableford WT McCormick P Seeman P Houle S Wilson AA 《Synapse (New York, N.Y.)》2006,60(4):314-318
Dopamine D2 partial agonists have been successfully used as schizophrenia therapeutics. Radiolabeled D2 partial agonists may have application in elucidating dopaminergic transmission. It was the goal of this work to radiolabel (S)-(-)propyl-3-(3-hydroxyphenyl)piperidine (preclamol; (-)3-PPP), a partial dopamine D2 agonist with carbon-11 (half-life=20.4 min) and to evaluate this novel radiopharmaceutical for dopaminergic imaging in rodent models. [11C]Preclamol was synthesized by acylation of (S)-3-(3-hydroxyphenyl)piperidine hydrochloride with [11C]propionyl chloride, followed by LiAlH4 reduction, and HPLC purification. Male Sprague-Dawley rats were injected in the tail vein with a saline solution of [11C]preclamol (1.1 mug/kg) and sacrificed at 5, 15, 30 and 60 min postinjection. Brain regions were excised, weighed, and measured for radioactivity. In vivo binding kinetics of [11C]preclamol were determined with beta-sensitive microprobes implanted into the striatum and cerebellum of an anesthetized rat. A full production of [11C]preclamol resulted in 34 mCi ready for injection (corresponding to 4% uncorrected radiochemical yield, based on starting [11C]CO2) with specific activity of 535 mCi/micromol. The total synthesis time was 45 min and resulted in chemically and radiochemically pure [11C]preclamol (>99%; n=3). High levels of radioactivity were observed in rat brain indicating good blood-brain barrier penetration of [11C]preclamol, with 0.5 to 0.7% injected dose per gram of wet tissue present in all brain regions at 5 minutes postinjection. Unfortunately, [11C]preclamol displayed minimal preferential uptake in dopaminergic brain regions. A low striatal specific binding (SB) ratio of 0.32 was determined ex vivo at 60 min postinjection and was in close agreement with the microprobe study over 60 min (peaked at 27 min postinjection; SB ratio=0.6). The binding potential value was only 0.34 over a 1 hour time course, suggesting that [11C]preclamol is not suitable for cerebral PET studies. 相似文献
39.
Objectives
We aimed to measure early fetal growth velocity and to correlate this with the birth weight, gestational age at delivery, and with the incidence of adverse pregnancy outcomes specifically preeclampsia and perinatal mortality.Methods
A data based prospective observational study, wherein sonographic biometry data and specific pregnancy outcome related data were collected from pregnant women's records, starting soon after their first antenatal visit. Early fetal growth velocity was measured using BPD growth between 11 and 14 weeks scan and anomaly scan and standardizing this by Z scoring.Results
Out of 607 fetuses, 41 (6.7%) were slow growing, 531 (87.4%) normally growing, and 35 (5.7%) fast growing (Z scoring <10th, 10–90th, and >90th percentiles respectively). As fetal growth velocity increased, the mean birth weight decreased from 2958.7 ± 388.9 (<10th centile), 2742.1 ± 576.6 (10–90th centile), to 2339.3 ± 729.4 (>90th centile); and gestational age at delivery decreased from 38.5 ± 1.3 (<10th centile), 37.5 ± 2.1 (10–90th centile), to 36.4 ± 2.2 (>90th centile), and both these trends were statistically significant (p < 0.001).Faster growing fetuses had a higher risk of preterm delivery(spontaneous + indicated) compared to other 2 groups [OR 4.42 (2.18,8.98)], and slower growing fetuses had a higher risk of postdated deliveries compared to other 2 groups [OR 3.042 (1.44, 6.45)].We found no significant association between early fetal growth velocity and incidence of small for gestational age at birth/low birth weight at term, preeclampsia, and perinatal mortality.Conclusions
Early fetal growth velocity between first and second trimesters, may be one of the important factors influencing ultimate birthweight and gestational age at delivery. 相似文献40.
Metabolic bone diseases are serious health issues worldwide, since several million individuals over the age of 50 are at risk of bone damage and should be worried about their bone health. One in every two women and one in every four men will break a bone during their lifetime due to a metabolic bone disease. Early detection, raising bone health awareness, and maintaining a balanced healthy diet may reduce the risk of skeletal fractures caused by metabolic bone diseases. This review compiles information on the most common metabolic bone diseases (osteoporosis, primary hyperparathyroidism, osteomalacia, and fluorosis disease) seen in the global population, including their symptoms, mechanisms, and causes, as well as discussing their prevention and the development of new drugs for treatment. A large amount of research literature suggests that balanced nutrition and balanced periodic supplementation of calcium, phosphate, and vitamin D can improve re-absorption and the regrowth of bones, and inhibit the formation of skeletal fractures, except in the case of hereditary bone diseases. Meanwhile, new and improved drug formulations, such as raloxifene, teriparatide, sclerostin, denosumab, and abaloparatide, have been successfully developed and administered as treatments for metabolic bone diseases, while others (romososumab and odanacatib) are in various stages of clinical trials. 相似文献