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961.
High-yield isolation, expansion, and differentiation of murine bone marrow-derived mesenchymal stem cells using fibrin microbeads (FMB) 总被引:1,自引:0,他引:1
Rivkin R Ben-Ari A Kassis I Zangi L Gaberman E Levdansky L Marx G Gorodetsky R 《Cloning and stem cells》2007,9(2):157-175
Transplantation of adult mesenchymal stem cells (MSCs) could provide a basis for tissue regeneration. MSCs are typically isolated from bone marrow (BM) based on their preferential adherence to plastic, although with low efficiency in terms of yield and purity. Extensive expansion is needed to reach a significant number of MSCs for any application. Fibrin microbeads (FMB) were designed to attach mesenchymal cells and to provide a matrix for their expansion. The current study was aimed at isolating a high yield of purified BM-derived mouse MSCs based on their preferential adherence and proliferation on FMB in suspension cultures. MSCs could be downloaded to plastics or further expanded on FMB. The yield of MSCs obtained by the FMB isolation technique was about one order of magnitude higher than that achieved by plastic adherence, suggesting that these cells are more abundant than previously reported. FMB-isolated cells were classified as MSCs by their fibroblastic morphology, self-renewal ability, and expression profile of their surface antigens, as examined by flow cytometry and immunostaining. In cell culture, the isolated MSCs could be induced to differentiate into three different mesodermal lineages, as demonstrated by histochemical stains and by RT-PCR analyses of tissue-specific genes. MSCs were also able to differentiate into osteocytes while still cultured on FMB. Our results suggest that FMB might serve as an efficient platform for the isolation, expansion, and differentiation of mouse BM-derived MSCs to be subsequently implanted for tissue regeneration. 相似文献
962.
Micromolar and millimolar Ca2+-requiring neutral protease (calpain I and calpain II) along with their endogenous inhibitor calpastatin were isolated and partially purified from the same preparation of rat intestinal epithelial cells. Calpain I and II were partially purified by 1300 and 900-fold with 57 and 53 per cent yield, respectively. The optimum assay conditions revealed pH 7.5, 20 min incubation at 25° C and 0.24% casein substrate for both calpains. The optimum calcium concentration obtained for calpain I and II were 25 M and 4 mM, respectively. Distribution of rat intestinal epithelial cells calpain I and II along with calpastatin during cell differentiation stages in weanling to senescence age were studied. Calpain I in weanling rats was in an increasing order from villus to crypt regions. Adult rats indicated well expressed consistent calpain I throughout the differentiation stages. Whereas, significant lowering towards crypt region cells were evident in old rats. Calpain II in weanling and adult rats was found to be consistent throughout the differentiation stages. Old animals revealed an increasing trend from villus to crypt region with insignificant activity present in upper villus cells. Concomitantly, different concentrations of calpastatin were observed throughout the differentiation stages in all the age groups. Moreover, the levels of calpains exceeded that of calpastatin in most of the epithelial cell populations during developmental stages. In addition to casein, intestinal epithelial cell membranes were found to be equally good substrates for calpains. Proteolytic susceptibility of weanling, adult and old rat membrane proteins varied significantly all along the ageing process in rats. Simultaneous age-dependent calpastatin response were also evident. Taken together the results obtained provided strong evidence that calpain plays significant role in rat intestinal cell differentiation and ageing process with calpastatin as its specific regulatory protein.Abbreviations DEAE-cellulose
O-(Diethylaminoethyl)-cellulose
- EDTA
Ethylene Diamine Tetra Acetic Acid
- Tris
Tris (hydroxymethyl) amino methane
- KH2PO4
potassium dihydrogen orthophosphate
- Na2HPO4
disodium hydrogen phosphate
- CaCl2
Calcium Chloride
- TCA
Trichloroacetic Acid
- PMSF
Phenylmethylsulfonyl Fluoride 相似文献
963.
Leather industries release a large amount of pollution-causing chemicals which creates one of the major industrial pollutions. The development of enzyme based processes as a potent alternative to pollution-causing chemicals is useful to overcome this issue. Proteases are enzymes which have extensive applications in leather processing and in several bioremediation processes due to their high alkaline protease activity and dehairing efficacy. In the present study, we report cloning, characterization of a Mn2+ dependent alkaline serine protease gene (MASPT) of Bacillus pumilus TMS55. The gene encoding the protease from B. pumilus TMS55 was cloned and its nucleotide sequence was determined. This gene has an open reading frame (ORF) of 1,149 bp that encodes a polypeptide of 383 amino acid residues. Our analysis showed that this polypeptide is composed of 29 residues N-terminal signal peptide, a propeptide of 79 residues and a mature protein of 275 amino acids. We performed bioinformatics analysis to compare MASPT enzyme with other proteases. Homology modeling was employed to model three dimensional structure for MASPT. Structural analysis showed that MASPT structure is composed of nine α-helices and nine β-strands. It has 3 catalytic residues and 14 metal binding residues. Docking analysis showed that residues S223, A260, N263, T328 and S329 interact with Mn2+. This study allows initial inferences about the structure of the protease and will allow the rational design of its derivatives for structure-function studies and also for further improvement of the enzyme. 相似文献
964.
Mazhar Ali Nasir Masood Hafiz Muhammad Rashad Javeed Ibrahim Al-Ashkar Khalid F. Almutairi Liyun Liu Muhammad Aqeel Sarwar Karthika Rajendran Ayman EL Sabagh 《Phyton》2022,91(10):2235-2248
Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity,
and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical
properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite
species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis
that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles
were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC)
and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that
EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were
transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed
that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the
termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme
indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings
revealed that transportation preferences were observed among the four termite species. In conclusion, the current
study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these
have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes
heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was
necessary to conduct additional research into the effect of temperature on the transportation process. 相似文献
965.
Richard A. Bryant Aiysha Malik Ibrahim Said Aqel Maha Ghatasheh Rand Habashneh Katie S. Dawson Sarah Watts Mark J. D. Jordans Felicity L. Brown Mark van Ommeren Aemal Akhtar 《PLoS medicine》2022,19(8)
BackgroundMillions of young adolescents in low- and middle-income countries (LMICs) affected by humanitarian crises experience elevated rates of poor mental health. There is a need for scalable programs that can improve the mental health of young adolescents. This study evaluated the effectiveness of a nonspecialist delivered group-based intervention (Early Adolescent Skills for Emotions (EASE)) to improve young adolescents’ mental health.Methods and findingsIn this single-blind, parallel, controlled trial, Syrian refugees aged 10 to 14 years in Jordan were identified through screening of psychological distress as defined by scores ≥15 on the Paediatric Symptom Scale. Participants were randomised to either EASE or enhanced usual care (EUC) involving referral to local psychosocial services (on a 1:1.6 ratio). Participants were aware of treatment allocation but assessors were blinded. Primary outcomes were scores on the Paediatric Symptom Checklist (PSC; internalising, externalising, and attentional difficulty scales) assessed at week 0, 9 weeks, and 3 months after treatment (primary outcome time point). It was hypothesised that EASE would result in greater reductions on internalising symptoms than EUC. Secondary outcomes were depression, posttraumatic stress, well-being, functioning, school belongingness, and caregivers’ parenting and mental health. Between June 2019 and January 2020, 1,842 young adolescent refugees were screened for eligibility on the basis of psychological distress. There were 520 adolescents (28.2%) who screened positive, of whom 471 (90.6%) agreed to enter the trial. Overall, 185 were assigned to EASE and 286 to EUC, and 169 and 254 were retained at 3 months for EASE and EUC, respectively. Intent-to-treat analyses indicated that at 3 months, EASE resulted in greater reduction on the PSC-internalising scale than EUC (estimated mean difference 0.69, 95% CI 0.19 to 1.19; p = 0.007; effect size, 0.38) but there were no differences for PSC-externalising (estimated mean difference 0.24, 95% CI −0.43 to 0.91; p = 0.49; effect size, −0.10), PSC-attentional problem (estimated mean difference −0.01, 95% CI −0.51 to 0.54; p = 0.97; effect size, −0.01) scores, or on depression, posttraumatic stress, well-being, functioning, or school belongingness. Relative to EUC, caregivers in EASE had less psychological distress (estimated mean difference 1.95, 95% CI 0.71 to 3.19; p = 0.002) and inconsistent disciplinary parenting (mean difference 1.54, 95% CI 1.03 to 2.05; p < 0.001). Secondary analyses that (a) focused on adolescents with probable internalising disorders; (b) completed the 3-month assessment; and (c) controlled for trauma exposure did not alter the primary results. Mediation analysis indicated that for caregivers in the EASE condition, reduction in inconsistent disciplinary parenting was associated with reduced attentional (β = 0.11, SE 0.07; 95% CI 0.003, 0.274) and internalising (β = 0.11, SE 0.07; 95% CI 0.003, 0.274) problems in their children. No adverse events were attributable to the intervention. A limitation was that EUC was not matched to EASE in terms of facilitator attention or group involvement.ConclusionsEASE led to reduced internalising problems in young refugee adolescents and was associated with reduced distress and less inconsistent disciplinary parenting in caregivers. This intervention has the potential as a scalable intervention to mitigate young adolescents’ emotional difficulties in LMIC.Trial registrationProspectively registered at Australian and New Zealand Clinical Trials Registry: ACTRN12619000341123.In a randomized controlled trial, Richard A. Bryant and colleagues study the effectiveness of the Early Adolescent Skills for Emotions (EASE) intervention to improve the mental health of Syrian refugees aged 10-14 years living in Jordan. 相似文献
966.
967.
Shankargouda Patil Hytham N. Fageeh Hammam Ibrahim Fageeh Wael Ibraheem Abdulrahman Saleh Alshehri Ashraf Al-Brakati Salem Almoammar Mohammad Almagbol Harisha Dewan Samar Saeed Khan Hosam Ali Baeshen Vikrant R Patil A. Thirumal Raj Shilpa Bhandi 《Saudi Journal of Biological Sciences》2022,29(5):3568-3576
Gingival mesenchymal stem cells (GMSCs) have significant regenerative potential. Their potential applications range from the treatment of inflammatory diseases, wound healing, and oral disorders. Preconditioning these stem cells can optimize their biological properties. Hypoxia preconditioning of MSCs improves stem cell properties like proliferation, survival, and differentiation potential. This research explored the possible impact of hypoxia on the pluripotent stem cell properties that GMSCs possess. We evaluated the morphology, stemness, neurotrophic factors, and stemness-related genes. We compared the protein levels of secreted neurotrophic factors between normoxic and hypoxic GMSC-conditioned media (GMSC-CM). Results revealed that hypoxic cultured GMSC’s had augmented expression of neurotrophic factors BDNF, GDNF, VEGF, and IGF1 and stemness-related gene NANOG. Hypoxic GMSCs showed decreased expression of the OCT4 gene. In hypoxic GMSC-CM, the neurotrophic factors secretions were significantly higher than normoxic GMSC-CM. Our data demonstrate that culturing of GMSCs in hypoxia enhances the secretion of neurotrophic factors that can lead to neuronal lineage differentiation. 相似文献
968.
Jie Zhang Ting He Wei Zhang Jinzhi Sheng Ibrahim Saana Amiinu Zongkui Kou Jinlong Yang Liqiang Mai Shichun Mu 《Liver Transplantation》2017,7(5)
Searching for a new material to build the next‐generation rechargeable lithium‐ion batteries (LIBs) with high electrochemical performance is urgently required. Owing to the low‐cost, non‐toxicity, and high‐safety, the family of manganese oxide including the Na‐Mn‐O system is regarded as one of the most promising electrode materials for LIBs. Herein, a new strategy is carried out to prepare a highly porous and electrochemically active Na0.55Mn2O4·1.5H2O (SMOH) compound. As an anode material, the Na‐Mn‐O nanocrystal material dispersed within a carbon matrix manifests a high reversible capacity of 1015.5 mA h g?1 at a current density of 0.1 A g?1. Remarkably, a considerable capability of 546.8 mA h g?1 remains even after 2000 discharge/charge cycles at the higher current density of 4 A g?1, indicating a splendid cyclability. The exceptional electrochemical properties allow SMOH to be a promising anode material toward LIBs. 相似文献
969.
Hydrogen as an electron donor for sulfate-reducing bacteria in slurries of salt marsh sediment 总被引:2,自引:0,他引:2
Experiments with a Warburg respirometer showed that a sediment slurry consumed hydrogen from a hydrogen atmosphere, and this
consumption was not due to the activity of methanogenic bacteria. The hydrogren uptake was inhibited by the addition of 20
mM molybdate. Further experiments with sediment slurry held in conical flasks under an atmosphere of nitrogen showed that
hydrogen accumulated in the headspace when bacterial sulfate reduction was inhibited either by the addition of 20 mM molybdate
or by low (<5 mM) sulfate concentrations in the slurry. Methanogenesis was stimulated in the presence of a hydrogen atmosphere
or by the addition of 20 mM molybdate. The results confirmed that hydrogren was an important electron donor for sulfate-reducing
bacteria present in the sediment. The stimulation of methanogenesis by molybdate could be explained in part by a competition
for hydrogen between sulfate-reducing bacteria and hydrogen-metabolizing methanogenic bacteria, but competition for another
common substrate, possibly acetate, could also be significant. 相似文献
970.
Pallab Datta Ananya Barui Yang Wu Veli Ozbolat Kazim K. Moncal Ibrahim T. Ozbolat 《Biotechnology advances》2018,36(5):1481-1504
An increasing demand for directed assembly of biomaterials has inspired the development of bioprinting, which facilitates the assembling of both cellular and acellular inks into well-arranged three-dimensional (3D) structures for tissue fabrication. Although great advances have been achieved in the recent decade, there still exist issues to be addressed. Herein, a review has been systematically performed to discuss the considerations in the entire procedure of bioprinting. Though bioprinting is advancing at a rapid pace, it is seen that the whole process of obtaining tissue constructs from this technique involves multiple-stages, cutting across various technology domains. These stages can be divided into three broad categories: pre-bioprinting, bioprinting and post-bioprinting. Each stage can influence others and has a bearing on the performance of fabricated constructs. For example, in pre-bioprinting, tissue biopsy and cell expansion techniques are essential to ensure a large number of cells are available for mass organ production. Similarly, medical imaging is needed to provide high resolution designs, which can be faithfully bioprinted. In the bioprinting stage, compatibility of biomaterials is needed to be matched with solidification kinetics to ensure constructs with high cell viability and fidelity are obtained. On the other hand, there is a need to develop bioprinters, which have high degrees of freedom of movement, perform without failure concerns for several hours and are compact, and affordable. Finally, maturation of bioprinted cells are governed by conditions provided during the post-bioprinting process. This review, for the first time, puts all the bioprinting stages in perspective of the whole process of bioprinting, and analyzes their current state-of-the art. It is concluded that bioprinting community will recognize the relative importance and optimize the parameter of each stage to obtain the desired outcomes. 相似文献