Human neural progenitor cells (hNPCs) are currently believed to have important potential for clinical application and basic neuroscience research. In the present study, we have developed a new ...technique for expansion of human neural progenitor cells in vitro. We showed that the cultures of hNPCs in monolayer could keep the same features with that growing in neurospheres. These cells expressed the typical protein of neural progenitors, nestin, and could form neurons and astrocytes upon differentiation. Using this method, we achieved an exponential increase in cells number over a period of 240 days in vitro. We also confirmed these cells expressed the orphan nuclear receptor-related factor 1 (Nurr1). Furthermore, we acquired the GFP-expressing human neural progenitor cells using retroviral-mediated transgenic system. The results of present study indicate the feasibility of long-term in vitro expansion of human neural progenitor cells using the monolayer culture technique, which may be of value as vehicles for ex vivo gene transfer to the CNS and as a potential source for basic research of dopaminergic (DA) neurons development.
We investigated the effects of UDCA on sphingomyelinase (SMase) in Caco 2 cells cultured in monolayer and polarized conditions. Alkaline SMase activity was high in polarized cells whereas, acid and ...neutral SMase activities were high in monolayer cells. In polarized cells, UDCA increased alkaline SMase expression and caspase 3 activity but had no effect on acid and neutral SMases. In monolayer cells, UDCA reduced both acid and neutral SMase activities, inhibited cell proliferation, but had little effect on alkaline SMase and caspase 3 activities. In conclusion, UDCA differentially affects SMase activity, cell proliferation, and apoptosis in colonic cells depending on the cell conditions.
Comparison between adult and infant lung injury in a rabbit ischemia-reperfusion model Qiu, Wanshan, MD; Zheng, Liang, MD; Gu, Haiyong, MD ...
Journal of thoracic and cardiovascular surgery/The Journal of thoracic and cardiovascular surgery/The journal of thoracic and cardiovascular surgery,
08/2008, Letnik:
136, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Objective Ischemia-reperfusion causes lung damage to patients with congenital heart disease who undergo open surgery under total cardiopulmonary bypass. The aim of the present study was to compare ...ischemia-reperfusion–induced lung damage between adults and infants. Methods Both infant (15 to 21-day-old) and adult (5 to 6-month-old) rabbits were subjected to either ischemia-reperfusion or sham operation. Ischemia-reperfusion was induced by clamping the right pulmonary hilum for 1 hour and then removing the clamp for 4 hours. The lung tissue samples were collected for histologic examination by light and electron microcopies and for biological evaluation of mitochondrial alterations. Blood samples were taken for measurement of interleukin-1β and tumor necrosis factor-α. Differences among the groups were analyzed by 2-way analysis of variance. Results In comparison with adult lungs, the infant lungs had increased neutrophil infiltration, edema, swollen alveolar epithelial and endothelial cells, and severe mitochondrial impairment reflected by reduced swelling rate and membrane potential, intramitochondrial free Ca2+ levels after ischemia-reperfusion. The infant lungs produced higher levels of hydroxyl radical and malondialdehyde and lower levels of superoxide dismutase and glutathione peroxidase than adult lungs, especially after ischemia-reperfusion. The circulating levels of interleukin-1β and tumor necrosis factor-α were elevated during ischemia-reperfusion, particularly in the infants, which appeared to be associated with the expression of myeloid differentiation factor-88 and nuclear factor-κB in the lungs. Conclusion Lung ischemia-reperfusion causes more severe lung damage in infants than in adults, probably because of the combination of low antioxidant capacity and overproduction of reactive oxygen species in infants.
Under the short utterance environment, the total variability space underestimates the distribution of speech probabilities, which leads to a decline in speaker verification performance. Aiming at the ...above problems, a method of enhancing speaker identity vectors based on total variability space and time delay neural network (TDNN) is proposed. The purpose is to learn the linear correlation between the total variability space and TDNN, extract the speaker embeddings and project them on the new space, and then combine them into a new speaker supervector in order to enhance speaker information. In the training phase, this method separately trains the total variability space and TDNN. It creates a new irrelevant speaker set, extracts the i-vector and x-vector from it and gets the projection matrix under canonical correlation analysis (CCA). In the registration and testing phase, the embeddings of the registration and testing speakers are extracted, mapped in a new space through the projection matrix, and then the
Abstract Objective The objective was to assess the effects of pulse indicator continuous cardiac output catheterization on the management of critically ill patients and the alteration of therapy in ...intensive care units. Methods One hundred thirty-two patients with primary physiological abnormalities of hypotension or hypoxemia were evaluated. Prior to catheterization, physicians were asked to complete a questionnaire that collected information regarding predictions of the ranges of several hemodynamic variables and plans for therapy. After catheterization, each chart was reviewed by a panel of intensive care attending physicians to determine the possibility of altering the therapy. Results Overall correct classification of the key variables ranged from 46.0% to 65.4%. Catheterization results prompted alterations in therapy for 45.5% of patients. The fellows were less accurate in predicting hemodynamic values for patients whose diagnoses were unknown, and the primary abnormality was hypotension. There was significant difference in the physicians’ abilities to predict the hemodynamics for the subgroups with and without acute myocardial infarction. When the patients were divided into 3 subgroups by Acute Physiology and Chronic Health Evaluation II and Sepsis-related Organ Failure Assessment scores, the fellows had the most difficulty predicting the variables of the moderately ill patients in the middle subgroup, which led to the greatest percentage of therapy alterations for this subgroup; and this difference was significant. Conclusions The hemodynamic variables obtained from pulse indicator continuous cardiac output catheterization improved the accuracy of bedside evaluations and led to alterations in therapeutic plans, particularly among the moderately ill patients with hypotension or unknown diagnoses.
The hydrolysis of sphingomyelin (SM) generates key molecules regulating cell growth. Animal cancer studies support an inhibitory role for this pathway in the malignant transformation of the colonic ...mucosa. The activity of a specific intestinal alkaline sphingomyelinase (SMase), which hydrolyzes SM, is reduced in colorectal tumors. In this study we measured alkaline SMase activity in patients with longstanding colitis and assessed if a reduction can be used as a marker in surveillance of high risk patients.
Alkaline SMase activity was measured in 139 colonic biopsies from 34 patients with longstanding, extensive colitis and from 11 controls. Fifteen patients had earlier diagnosis of dysplasia or DNA aneuploidy. Alkaline SMase activity was related to histologic dysplasia and DNA aneuploidy assessed by flow cytometry, patient age, and duration of disease.
Alkaline SMase activity was significantly lower in the patient group with and without dysplasia compared with controls (p = 0.006). In biopsies, an association was not found between alkaline SMase activity, dysplasia, or DNA ploidy. However, alkaline SMase activity decreased with age both in patients and controls (p = 0.008).
Reduction of alkaline SMase activity seen in colorectal cancer and adenomas is also present in patients with chronic colitis. It is not complementary to dysplasia or DNA-aneuploidy in the identification of high risk patients. The age-associated decrease of alkaline SMase activity seems to be a general phenomenon indicating premature senescence of the mucosa in longstanding colitis.
Abstract Objective This study was aimed to evaluate the safety and feasibility of total endovascular repair of aortic arch using a novel designed stent-graft system (The Yanger stent-graft system) in ...vitro and in a canine model. Methods The Yanger stent-graft system is composed of a main stent-graft, branched stent-graft and a delivery system. In an in vitro aortic arch simulation test bench, the system was tested and the success rate of stent-graft releasing, anchoring and positioning was recorded and analyzed. Meanwhile, in vivo implantation of the Yanger stent-graft system was carried out in 16 healthy adult crossbreed dogs. The feasibility of using these stent grafts was evaluated with aortography, multi-sliced CT and autopsy six months following the procedure. Results All stent-graft releasing and positioning were successful for in vitro test. In the canine model, the Yanger stent-graft system was placed successfully in aortic arch in all fourteen dogs with the exception of 2 mortalities. All dogs survived for at least three months with normal physiological signs. Aortography, MSCT and animal necropsy revealed good fixation in all cases. The ascending aorta, descending aorta, brachiocephalic trunk and left subclavian artery were all covered without endoleak. There was no significant obstruction or stenosis in brachiocephalic branches at the 6-month follow-up. Conclusions Total endovascular repair of aortic arch with the novel designed Yanger stent-graft system is safe and feasible in pre-clinical studies. With a better understanding of preclinical knowledge, patient selection criteria and first-in-human studies will be addressed.
: Inter‐simple sequence repeat (ISSR) analysis was used to assess genetic diversity among 10 pairs of male and female Laminaria gametophytes. A total of 58 amplification loci was obtained from 10 ...selected ISSR primers, of which 34 revealed polymorphism among the gametophytes. Genetic distances were calculated with the Dice coefficient ranging from 0.006 to 0.223. A dendrogram based on the unweighted pair‐group method arithmetic (UPGMA) average showed that most male and female gametophytes of the same species were clustered together and that 10 pairs of gametophytes were divided into four groups. This was generally consistent with the taxonomic categories. The main group consisted of six pairs of gametophytes, which were selected from Laminaria japonica Aresch. by intensive inbreeding through artificial hybridization. One specific marker was cloned, but was not converted successfully into a sequence characterized amplified region (SCAR) marker. Our results demonstrate the feasibility of applying ISSR markers to evaluate Laminaria germplasm diversities.
(Managing editor: Li‐Hui ZHAO)
The hydrophilic porous glass membranes were used to demulsify water-in-oil emulsion, and demulsification efficiency can reach more than 96.2%. Effects of pore size of the membrane, transmembrane ...pressure and volumetric ratio of oil phase to internal aqueous phase in the emulsion on demulsification were investigated. It was found that pore size of membrane and transmembrane pressure can significantly affect demulsification efficiency. The smaller the pore size of the membrane, the better the demulsification efficiency. However, smaller pore size of the membrane has to be exerted a greater transmembrane pressure in order to make internal aqueous phase enter the membrane pore. Correspondingly, effect of transmembrane pressure on permeation flux of the droplets was also studied. In addition, recovered-oil phase by the demulsification were reused five times to extract cadmium from simulated aqueous waste. The results indicated that the extracting efficiency could arrive at 96.5%.