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1.
Stem Cell Res Ther ; 14(1): 173, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403181

RESUMO

BACKGROUND: Polyploid cells can be found in a wide evolutionary spectrum of organisms. These cells are assumed to be involved in tissue regeneration and resistance to stressors. Although the appearance of large multinucleated cells (LMCs) in long-term culture of bone marrow (BM) mesenchymal cells has been reported, the presence and characteristics of such cells in native BM and their putative role in BM reconstitution following injury have not been fully investigated. METHODS: BM-derived LMCs were explored by time-lapse microscopy from the first hours post-isolation to assess their colony formation and plasticity. In addition, sub-lethally irradiated mice were killed every other day for four weeks to investigate the histopathological processes during BM regeneration. Moreover, LMCs from GFP transgenic mice were transplanted to BM-ablated recipients to evaluate their contribution to tissue reconstruction. RESULTS: BM-isolated LMCs produced mononucleated cells with characteristics of mesenchymal stromal cells. Time-series inspections of BM sections following irradiation revealed that LMCs are highly resistant to injury and originate mononucleated cells which reconstitute the tissue. The regeneration process was synchronized with a transient augmentation of adipocytes suggesting their contribution to tissue repair. Additionally, LMCs were found to be adiponectin positive linking the observations on multinucleation and adipogenesis to BM regeneration. Notably, transplantation of LMCs to myeloablated recipients could reconstitute both the hematopoietic system and BM stroma. CONCLUSIONS: A population of resistant multinucleated cells reside in the BM that serves as the common origin of stromal and hematopoietic lineages with a key role in tissue regeneration. Furthermore, this study underscores the contribution of adipocytes in BM reconstruction.


Assuntos
Transplante de Medula Óssea , Medula Óssea , Camundongos , Animais , Adiponectina , Hematopoese/efeitos da radiação , Células da Medula Óssea , Camundongos Transgênicos , Camundongos Endogâmicos C57BL
2.
IEEE Trans Neural Netw Learn Syst ; 33(1): 61-74, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33074825

RESUMO

This article proposes a prescribed adaptive backstepping scheme with new filter-connected switched hysteretic quantizer (FCSHQ) for switched nonlinear systems with nonstrict-feedback structure and time-delay. The system model is subjected to unknown functions, unknown delays, and unknown Bouc-Wen hysteresis nonlinearity. The coexistence of quantized input and actuator hysteresis may deteriorate the shape of hysteresis loop and, consequently, fail to guarantee the stability. To deal with this issue, a new FCSHQ is introduced to smooth the input hysteresis. This adaptive filter also provides us a degree of freedom at choosing the desired communication rate. The repetitive differentiations of virtual control laws and existing a lot of learning parameters in the neural network (NN)-based controller may result in an algebraic loop problem and high computational time, especially in a nonstrict-feedback form. This challenge is eased by the key advantage of NNs' property where the upper bound of the weight vector is employed. Then, by an appropriate Lyapunov-Krasovskii functional, a common Lyapunov function is presented for all subsystems. It is shown that the proposed controller ensures the predefined output tracking accuracies and boundedness of the closed-loop signals under any arbitrary switching. Finally, the proposed control scheme is verified on a practical example where simulation results demonstrate the effectiveness of the proposed scheme.

3.
Biomedicines ; 9(1)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477721

RESUMO

Vasopressins are evolutionarily conserved peptide hormones. Mammalian vasopressin functions systemically as an antidiuretic and regulator of blood and cardiac flow essential for adapting to terrestrial environments. Moreover, vasopressin acts centrally as a neurohormone involved in social and parental behavior and stress response. Vasopressin synthesis in several cell types, storage in intracellular vesicles, and release in response to physiological stimuli are highly regulated and mediated by three distinct G protein coupled receptors. Other receptors may bind or cross-bind vasopressin. Vasopressin is regulated spatially and temporally through transcriptional and post-transcriptional mechanisms, sex, tissue, and cell-specific receptor expression. Anomalies of vasopressin signaling have been observed in polycystic kidney disease, chronic heart failure, and neuropsychiatric conditions. Growing knowledge of the central biological roles of vasopressin has enabled pharmacological advances to treat these conditions by targeting defective systemic or central pathways utilizing specific agonists and antagonists.

4.
J Econ Race Policy ; 4(3): 113-114, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35299884
5.
J Cancer Res Ther ; 14(3): 614-618, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29893328

RESUMO

BACKGROUND AND AIM OF STUDY: Colorectal cancer (CRC) is among the most common cancers and accounts as the second leading cause of death from cancers in the world. RAD51 plays a crucial role in double-strand breaks repair of DNA. Single nucleotide polymorphisms within this gene could influence on the potential of DNA repair and in consequence on the susceptibility to various tumors such as CRC. This is the first report about the role of RAD51 polymorphisms in Iranian CRC susceptibility. The study was conducted to evaluate the association of 135G>C polymorphism of RAD51 gene with sporadic CRC in a subset of Iranian population. MATERIALS AND METHODS: The current case-control study was performed from 2013 to 2015. One hundred patients with sporadic CRC and one hundred controls were enrolled from two referral centers in Isfahan. All samples were genotyped for the RAD51 gene using polymerase chain reaction-restriction fragment length polymorphism assay. RESULTS: The results revealed no significant association between the RAD51 135G>C and sporadic CRC (odds ratio = 0.86, 95% confidence interval = 0.464-1.595). The frequency of genotypes and also alleles of the mentioned polymorphism were not significantly different between case and control groups (P = 0.2 and 0.4, respectively). CONCLUSION: The results suggest that RAD51 135G>C probably has not a crucial role in Iranian CRC risk and is not an important potential risk factor in molecular diagnostics of mentioned disease among Iranian population.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Rad51 Recombinase/genética , Estudos de Casos e Controles , Neoplasias Colorretais/epidemiologia , Feminino , Seguimentos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
6.
Ann Hum Biol ; 44(2): 175-179, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27282193

RESUMO

BACKGROUND: Y-chromosome short tandem repeats (Y-STRs) are genetic markers with practical applications in human identification and population studies. AIM: Here we present the allelic and haplotype frequencies of 8 Y-STR loci most commonly used in forensic medicine in 103 unrelated native males of Isfahan province, central part of Iran. SUBJECTS AND METHODS: The cases were selected on the basis of strict criteria to assure pure native populations of Isfahan origin. DNA extracted from peripheral blood samples and PCR amplified for each marker. Y-specific STR loci DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392 and DYS393 were included in this study. RESULTS: The most common alleles for each locus were: DYS19, allele 12; DYS385, allele 12; DYS389I, allele 13; DYS389II, allele 29; DYS390, allele 24; DYS391, allele 10; DYS392, allele 11; and DYS393, allele 13. Gene diversity value was calculated from the allelic frequency for each locus. The average gene diversity was 0.6518. A total of 101 haplotypes were observed in eight Y-specific STR loci, the haplotype diversity was raised to 0.986. CONCLUSION: The results revealed that a set of eight Y-specific STR loci were able to discriminate most of the male individuals in the population studied. A search through the Y Haplotype Reference Database demonstrated 21 matched haplotypes to 160,693 haplotypes, exclusively with Eurasian-European, Eurasian, and Eurasian-Indo Iranian populations.


Assuntos
Cromossomos Humanos Y/genética , Frequência do Gene , Repetições de Microssatélites , Polimorfismo Genético , Haplótipos , Humanos , Irã (Geográfico) , Masculino
7.
J Matern Fetal Neonatal Med ; 29(16): 2645-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26553322

RESUMO

OBJECTIVE: To design and evaluate a noninvasive protocol for prenatal diagnosis (PND) of ß-thalassemia, using cell free fetal DNA (cff-DNA) in maternal circulation. Traditional current PND which is mainly based on chorionic villous sampling (CVS), amplification refractory mutation system and sequencing holds as gold standard. METHODS: Ten thalassemia trait couples with distinct mutations for the husband and wife were included in this study. The mutations in carrier fathers were IVSI-1, IVSI-5, FR8/9 and CD44. After maternal plasma isolation and free DNA extraction, all samples subjected to designed protocol including DNA size separation on agarose gel, elution of DNA from the gel slices using a simple and efficient manual purification method, with or without whole genome amplification and the detection method was allele-specific real-time PCR. RESULTS: Presence or absence of the paternal mutant allele was correctly determined in all of cases and the accuracy of designed protocol was determined 100%. CONCLUSIONS: The protocol described here is very simple, inexpensive and easy to perform, but with satisfactory accuracy in detection of paternal mutations in cff-DNA. Due to the risk of fetal loss with current invasive sampling for PND, a noninvasive alternative is highly demanded in clinical setting.


Assuntos
DNA/sangue , Herança Paterna/genética , Mutação Puntual/genética , Diagnóstico Pré-Natal/métodos , Talassemia beta/diagnóstico , Talassemia beta/genética , Adulto , Feminino , Sangue Fetal/química , Feto , Testes Genéticos/métodos , Genótipo , Heterozigoto , Humanos , Masculino , Reação em Cadeia da Polimerase , Gravidez , Sensibilidade e Especificidade
8.
ARYA Atheroscler ; 11(Suppl 1): 74-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26261453

RESUMO

BACKGROUND: The objective of this clinical trial was to assess the effects of probiotic soy milk and soy milk on anthropometric measures and blood pressure (BP) in type 2 diabetic (T2D) patients. METHODS: A total of 40 patients with T2D, 35-68 years old, were assigned to two groups in this randomized, double-blind, controlled clinical trial. The patients in the intervention group consumed 200 ml/day of probiotic soy milk containing Lactobacillus planetarium A7 and those in control group consumed 200 ml/day of soy milk for 8 weeks. Anthropometric and BP measurements were performed according to standard protocols. For detecting within-group differences paired-sample t-tests was used and analysis of covariance was used for determining any differences between two groups. (The trial has been registered in the Iranian Registry of Clinical Trials, identifier: IRCT: IRCT201405265062N8). RESULTS: In this study, we failed to find any significant changes between probiotic soy milk and soy milk in term of body mass index (26.65 ± 0.68 vs. 26.33 ± 0.74, P = 0.300) and waist to hip ratio (1.49 ± 0.08 vs. 1.54 ± 0.1, P = 0.170). Although soy milk did not have any effect on BP, probiotic soymilk significantly decreased systolic (14.7 ± 0.48 vs. 13.05 ± 0.16, P = 0.001) and diastolic BP (10 ± 0.7 vs. 9.1 ± 1, P = 0.031). CONCLUSION: In our study, probiotic soy milk in comparing with soy milk did not have any beneficial effects on anthropometric measures in these patients. We need more clinical trial for confirming the effect of probiotic foods on anthropometric measure in diabetic patients. However, probiotic soy milk decreased systolic and diastolic BP significantly.

9.
Adv Biomed Res ; 4: 31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25709996

RESUMO

BACKGROUND: The aim of the present study was to comparison between cell-free placental messenger ribonucleic acid (mRNA) and Doppler ultrasound for the prediction of placental invasion in women with placenta accreta. MATERIALS AND METHODS: In this cross-sectional study, 50 pregnant women at risk for placenta accreta underwent color Doppler and assessment of cell-free placental mRNA. Real-time reverse-transcription polymerase chain reaction was used for measurement of cell-free placental mRNA in maternal plasma. Based on the findings at cesarean delivery and histological examination, patients were divided into two groups of women with and without placenta accrete. To compare of the mean of mRNA levels between the two groups we used independent t-test and to compare of the mean of age and gestational age at sonography we used Mann-Whitney test. For determination of sensitivity and specificity and the cut-off point of mRNA levels we used the receiver operating characteristic curve. RESULTS: A total of 50 women with a mean age of 30.24 ± 4.905 years entered the study and 12 (24%) patients were diagnosed with placenta accreta. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of Doppler ultrasound were 83.3%, 78.9%, 56% and 94%, respectively. Results of our study showed if we consider a cut-off point equal to 3.325, with sensitivity and specificity of 0.917 and 0.789, respectively and the sensitivity, specificity, PPV and NPV of mRNA with were cut-off point of 3.325 were 91.7%, 78.9%, 57.9% and 96.8%, respectively. CONCLUSIONS: Cell-free mRNA is an acceptable, easy made, functional test with sensitivity, specificity, PPV and NPV more than Doppler ultrasound for diagnosis and prediction of incidence of placenta accrete and we recommend the use of cell-free mRNA test for diagnosis of placenta accreta.

10.
Adv Biomed Res ; 3: 231, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25538917

RESUMO

BACKGROUND: The Streptococci are the pioneer strains in plaque formation and Streptococcus mutans are the main etiological agent of dental plaque and caries. In general, biofilm formation is a step-wise process, which begins by adhesion of planktonic cells to the surfaces. Evidences show that expression of glucosyltransferase B and C (gtfB and gtfC) and fructosyltransferase (ftf) genes play critical role in initial adhesion of S. mutans to the tooth surface which results in formation of dental plaques and consequently caries and other periodontal disease. MATERIALS AND METHODS: The aim of this study was to determine the effect of biosurfactants produced by a probiotic strain; Lactobacillus casei (ATCC39392) on gene expression profile of gftB/C and tft of S. mutans (ATCC35668) using quantitative real-time PCR. RESULTS: The application of the prepared biosurfactant caused dramatic down regulation of all the three genes under study. The reduction in gene expression was statistically highly significant (for gtfB, P > 0.0002; for gtfC, P > 0.0063, and for ftf, P > 0.0057). CONCLUSION: Considerable downregulation of all three genes in the presence of the prepared biosurfactant comparing to untreated controls is indicative of successful inhibition of influential genes in bacterial adhesion phenomena. In view of the importance of glucosyltransferase gene products for S.mutans attachment to the tooth surface which is the initial important step in biofilm production and dental caries, further research in this field may lead to an applicable alternative for successful with least adverse side effects in dental caries prevention.

11.
Adv Biomed Res ; 3: 169, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25221772

RESUMO

BACKGROUND: Streptococci are the main causative agents in plaque formation and mutans streptococci are the principle etiological agent of dental plaque and caries. The process of biofilm formation is a step-wise process, starting with adhesion of planktonic cells to the surfaces. It is now a well known fact that expression of glucosyltransferases (gtfs) and fructosyltransferase (ftf) genes play a critical role in the initial adhesion of Streptococcus mutans to the tooth surface, which results in the formation of dental plaques and consequently caries and other periodontal diseases. MATERIALS AND METHODS: In the present study, we have determined the effect of biosurfactants purified from Lactobacillus reuteri (DSM20016) culture on gene expression profile of gftB/C and fft of S. mutans (ATCC35668) using quantitative real-time polymerase chain reaction. RESULTS: The application of biosurfactant caused considerable down-regulation of the expression of all three genes under study. The reduction in gene expression was statistically very significant (P > 0.0001 for all three genes). CONCLUSIONS: Inhibition of these genes by the extracted L. reuteri biosurfactant shows the emergence of a powerful alternative to the presently practicing alternatives. In view of the importance of these gene products for S. mutans attachment to the tooth surface, which is the initial important step in biofilm production and dental caries, we believe that the biosurfactant prepared in this study could be considered as a step ahead in dental caries prevention.

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