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71.
Biologic properties of mesenchymal stem cells derived from bone marrow and adipose tissue 总被引:15,自引:0,他引:15
Izadpanah R Trygg C Patel B Kriedt C Dufour J Gimble JM Bunnell BA 《Journal of cellular biochemistry》2006,99(5):1285-1297
The biologic characteristics of mesenchymal stem cells (MSCs) isolated from two distinct tissues, bone marrow and adipose tissue were evaluated in these studies. MSCs derived from human and non-human primate (rhesus monkey) tissue sources were compared. The data indicate that MSCs isolated from rhesus bone marrow (rBMSCs) and human adipose tissue (hASCs) had more similar biologic properties than MSCs of rhesus adipose tissue (rASCs) and human bone marrow MSCs (hBMSCs). Analyses of in vitro growth kinetics revealed shorter doubling time for rBMSCs and hASCs. rBMSCs and hASCs underwent significantly more population doublings than the other MSCs. MSCs from all sources showed a marked decrease in telomerase activity over extended culture; however, they maintained their mean telomere length. All of the MSCs expressed embryonic stem cell markers, Oct-4, Rex-1, and Sox-2 for at least 10 passages. Early populations of MSCs types showed similar multilineage differentiation capability. However, only the rBMSCs and hASCs retain greater differentiation efficiency at higher passages. Overall in vitro characterization of MSCs from these two species and tissue sources revealed a high level of common biologic properties. However, the results demonstrate clear biologic distinctions, as well. 相似文献
72.
Abazar Yari Mohammad Hossein Asadi Hossein Bahadoran Hossein Dashtnavard Hossein Imani Mohammad Reza Naghii 《Biological trace element research》2010,137(2):216-225
In this study, the effects of cadmium toxicity and the protective effects of l-carnitine on spermatogenesis in Sprague–Dawley rat were evaluated. Animals were subdivided into five groups. Cadmium chloride
(1-mg/kg body weight) was injected intraperitoneally during 16 days at intervals of 48 h between subsequent treatments. l-Carnitine (500 mg/kg b.w., IP) was pretreated in both of control and cadmium-injected rats. Animals were killed on day 17
after the first treatment. The left cauda epididymis was removed and immediately immersed into Hank’s balanced salt solution
for evaluation of sperm count and viability. Following contamination with cadmium, a decrease in the number and viability
of cauda epididymis sperm, the number of cell proliferation, and Johnsen Scores in the seminiferous tubules was observed.
Consequently, l-carnitine treatment caused an increase in the number and viability of cauda epididymis sperm, the number of cell proliferation,
and Johnsen Scores in the cadmium-induced group. 相似文献
73.
Amin MS Wang HW Reza E Whitman SC Tuana BS Leenen FH 《American journal of physiology. Regulatory, integrative and comparative physiology》2005,289(6):R1787-R1797
Epithelial sodium channels (ENaC) are important for regulating sodium transport across epithelia. Functional studies indicate that neural mechanisms acting through mineralocorticoid receptors (MR) and sodium channels (presumably ENaC) are crucial to the development of sympathoexcitation and hypertension in experimental models of salt-sensitive hypertension. However, expression and localization of the ENaC in cardiovascular regulatory centers of the brain have not yet been studied. RT-PCR and immunohistochemistry were performed to study ENaC and MR expression at the mRNA and protein levels, respectively. Both mRNA and protein for alpha-, beta-, and gamma-ENaC subunits and MR were found to be expressed in the rat brain. All three ENaC subunits and MR were present in the supraoptic nucleus, magnocellular paraventricular nucleus, hippocampus, choroid plexus, ependyma, and brain blood vessels, suggesting the presence of multimeric channels and possible regulation by mineralocorticoids. In most cortical areas, thalamus, amygdala, and suprachiasmatic nucleus, notable expression of gamma-ENaC was undetectable, whereas alpha- and beta-ENaC were abundantly expressed pointing to the possibility of a heterogeneous population of channels. The findings suggest that stoichiometrically different populations of ENaC may be present in both epithelial and neural components in the brain, which may contribute to regulation of cerebrospinal fluid and interstitial Na+ concentration as well as neuronal excitation. 相似文献
74.
Eberth A Lundmark R Gremer L Dvorsky R Koessmeier KT McMahon HT Ahmadian MR 《The Biochemical journal》2009,417(1):371-377
The BAR (Bin/amphiphysin/Rvs) domain defines an emerging superfamily of proteins implicated in fundamental biological processes by sensing and inducing membrane curvature. We identified a novel autoregulatory function for the BAR domain of two related GAPs' (GTPase-activating proteins) of the GRAF (GTPase regulator associated with focal adhesion kinase) subfamily. We demonstrate that the N-terminal fragment of these GAPs including the BAR domain interacts directly with the GAP domain and inhibits its activity. Analysis of various BAR and GAP domains revealed that the BAR domain-mediated inhibition of these GAPs' function is highly specific. These GAPs, in their autoinhibited state, are able to bind and tubulate liposomes in vitro, and to generate lipid tubules in cells. Taken together, we identified BAR domains as cis-acting inhibitory elements that very likely mask the active sites of the GAP domains and thus prevent down-regulation of Rho proteins. Most remarkably, these BAR proteins represent a dual-site system with separate membrane-tubulation and GAP-inhibitory functions that operate simultaneously. 相似文献
75.
In the present study Cervatana and Almagra models from decision support system, MicroLEIS DSS, were applied to segregation
of arable land surfaces from the marginal ones and suitability evaluation of wheat (Triticum aestivum), maize (Zea mays) and alfalfa (Medicago sativa) in Souma area with approximately 4100 ha extension in West Azarbaijan. Obtained results from both models are presented and
discussed in this research work. Soil morphological and analytical data were collected from 35 soil profiles, representative
of the study area and stored in SDBm plus database. The control or vertical section of soil for applying and running the models
for annual selected crops, was calculated by soil layer generator 0.0–50 cm in depth, or between the surface and the limit
of useful depth when the latter is between 0.0 and 50 cm. According to results, 80.49% of the total area was good capable
for agricultural uses and 19.51% must be reforested and not dedicated to agriculture. The lands with good capability for agricultural
uses is classified as highly suitable area (S2) for wheat, maize and alfalfa, but results in 822 ha for maize and in 126 ha
for alfalfa refers to an excellent suitable (S1) and moderately suitable (S3) classes respectively. The most important limitation
factors are soil texture and carbonate alone or together and maize — wheat — alfalfa can be selected as the best crop rotation.
A simple map subsystem (ArcView GIS) was used for basic data and models result demonstration on a map. 相似文献
76.
Induction of disease by a molecularly cloned highly pathogenic simian immunodeficiency virus/human immunodeficiency virus chimera is multigenic 下载免费PDF全文
Sadjadpour R Theodore TS Igarashi T Donau OK Plishka RJ Buckler-White A Martin MA 《Journal of virology》2004,78(10):5513-5519
One of three full-length infectious molecular clones of SHIV(DH12R), designated SHIV(DH12R-CL-7) and obtained from productively infected rhesus monkey peripheral blood mononuclear cells, directed rapid and irreversible loss of CD4+ T cells within 3 weeks of its inoculation into Indian rhesus monkeys. Induction of complete CD4+ T-cell depletion by SHIV(DH12R-CL-7) was found to be dependent on inoculum size. The acquisition of this pathogenic phenotype was accompanied by the introduction of 42 amino acid substitutions into multiple genes of parental nonpathogenic SHIV(DH12). Transfer of the entire SHIV(DH12R-CL-7) env gene into the genetic background of nonpathogenic SHIV(DH12) failed to confer the rapid CD4+ T-lymphocyte-depleting syndrome; similarly, the substitution of gag plus pol sequences from SIV(smE543) for analogous SIV(mac239) genes in SHIV(DH12R-CL-7) attenuated the pathogenic phenotype. Amino acid changes affecting multiple viral genes are necessary, but insufficient by themselves, to confer the prototypically rapid and irreversible CD4+ T-cell-depleting phenotype exhibited by molecularly cloned SHIV(DH12R-CL-7). 相似文献
77.
Chhabra S Narang R Lakshmy R Vasisht S Agarwal DP Srivastava LM Manchanda SC Das N 《Molecular and cellular biochemistry》2004,259(1-2):59-66
Various population studies have reported the association of rare S2 allele of apolipoprotein C3 (APOC3) SstI polymorphism with hypertriglyceridemia (HTG) and coronary artery disease (CAD). We were the first to report an association of S2 allele with high triglyceride (TG) levels in healthy volunteers from Northern India. Since HTG is suggested to be a predominant risk factor for CAD among Indians, we have elucidated the relationship of APOC3 SstI polymorphism with the lipid profile and CAD. A total of 158 patients with > or = 70% stenosis in one or more coronary artery (angiographically proven CAD patients), 35 subjects with < 70% stenosis (NCAD) and 151 normal controls (free of heart disease) from Northern plains of India were recruited in the study. DNA samples were analyzed by polymerase chain reaction (PCR) followed by SstI digestion. Lipid profile was estimated by enzymatic kit. We found a strong association of S2 allele with high TG levels, which was more significant in patients. Prevalence of S2 allele in normal controls and CAD patients were comparable, despite the fact that mean TG level was significantly higher in patients. A greater insight into this observation revealed that the prevalence of high TG, if not coupled with other risk factors (like high total cholesterol, low HDL), was comparable in patients and controls. Thus, our study reveals that rare S2 allele may be employed as a susceptibility marker for high TG. However, high TG or S2 allele alone may not contribute to the etiology of CAD. 相似文献
78.
Holo transferrin (TF) and the natural complex of human serum albumin and protoporphyrin IX (HSA-PPIX) are two serum carrier proteins that can interact with each other. Such an interaction may alter their binding sites. In this study, fluorescence spectroscopy, as well as zeta potential and molecular modeling techniques, have been used to compare the complexes (HSA-PPIX)-LMF and [(HSA-PPIX)-TF]-LMF. The Ka1, Ka2, values of (HSA-PPIX)-LMF and [(HSA-PPIX)-TF]-LMF were 1.1×105 M−1, 9.7×106 M−1, and 2.0×104 M−1, 1.8×105 M−1, respectively, and the n1, n2 values were respectively 1.19, 1.53 and 1.17, 1.65. The second derivative of the Trp emission scan of (HSA-PPIX)-LMF exhibited one negative band at 310 nm, whereas for the [(HSA-PPIX)-TF]-LMF system, we observed one negative band at 316 nm indicating an increase in polarity around Trp. The effect of TF on the conformation of (HSA-PPIX)-TF was analyzed using three-dimensional fluorescence spectroscopy. The phase diagram indicated that the presence of a second binding site on HSA and TF was due to the existence of intermediate structures. Zeta potential analysis showed that the presence of TF increased the positive charges of the HSA-PPIX system. Site marker experiments revealed that the binding site of LMF to HSA-PPIX changed from Sudlow''s site IIA to Sudlow''s site IIIB in the presence of TF. Moreover, molecular modeling studies suggested the sub-domain IIIB in HSA as the candidate place for the formation of the binding site of LMF on the (HSA-PPIX)-TF complex. 相似文献
79.
Heidari Reza Farajzadeh Sheikh Ahmad Hashemzadeh Mohammad Farshadzadeh Zahra Salmanzadeh Shokrollah Saki Morteza 《Molecular biology reports》2022,49(5):3811-3822
Molecular Biology Reports - This study was aimed to evaluate the antibiotic resistance, biofilm formation, and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa (CRPA) strains... 相似文献
80.
Reza Jafarzadeh-Esfehani Seyed Mostafa Parizadeh Amirsaeed Sabeti Aghabozorgi Negar Yavari Ariane Sadr-Nabavi Seyed Alireza Parizadeh Maryam Ghandehari Afsane Javanbakht Afsaneh Rezaei-Kalat Seyed Mahdi Hassanian Mohammad Vojdanparast Gordon A. Ferns Majid Khazaei Amir Avan 《Journal of cellular physiology》2020,235(10):6393-6403
Venous and arterial thrombosis are conditions that have a considerable burden if left untreated. The hypoxia-induced by the occluded vessel can disrupt the circulation of any organ, the cornerstone of treating thrombosis is rapid diagnosis and appropriate treatment. Diagnosis of thrombosis may be made by using laboratory tests or imaging techniques in individuals who have clinical manifestations of a thrombotic event. The use of serum micro ribonucleic acids (RNAs) has recently been applied to the diagnosis of thrombosis. These small RNA molecules are emerging as new diagnostic markers but have had very limited applications in vascular disease. Most of the articles provided various microRNAs with different levels of accuracy. However, there remains a lack of an appropriate panel of the most specific microRNA in the literature. The purpose of the present review was to summarize the existing data on the use of microRNAs as a diagnostic biomarker for venous thrombosis. 相似文献