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1.
Mol Hum Reprod ; 22(4): 272-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26740067

RESUMO

STUDY HYPOTHESIS: The mouse endometrium harbours stem/progenitor cells that express the stem cell marker mouse telomerase reverse transcriptase (mTert). STUDY FINDING: We used a mouse carrying a transgenic reporter for mTert promoter activity to identify rare endometrial populations of epithelial and endothelial cells that express mTert. WHAT IS KNOWN ALREADY: Stem/progenitor cells are hypothesized to be responsible for the remarkable regenerative capacity of the endometrium, but the lack of convenient endometrial stem/progenitor markers in the mouse has hampered investigations into the identity of these cells. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: A mouse containing a green fluorescent protein (GFP) reporter under the control of the telomerase reverse transcriptase promoter (mTert-GFP) was used to identify potential stem/progenitor cells in the endometrium. mTert promoter activity was determined using fluorescence microscopy and flow cytometry to identify GFP(+) cells. GFP(+) cells were examined for epithelial, stromal, endothelial, leucocyte and proliferation markers and bromodeoxyuridine retention to determine their identity. The endometrium of ovariectomized mice was compared to that of intact cycling mice to establish the role of ovarian hormones in maintaining mTert-expressing cells. MAIN RESULTS AND THE ROLE OF CHANCE: We found that mTert-GFP is expressed by rare luminal and glandular epithelial cells (0.3% of epithelial cells by flow cytometry), rare CD45(-) cells in the stromal compartment (0.028 ± 0.010% of stromal cells by microscopy) and many CD45(+) leucocytes. Ovariectomy resulted in significant decrease of mTert-GFP(+) epithelial cells (P = 0.029 for luminal epithelium; P = 0.034 for glandular epithelium) and a decrease in the percentage of mTert-GFP(+) CD45(+) leucocytes in the stromal compartment (P = 0.015). However, CD45(-) mTert-GFP(+) cells in the stromal compartment were maintained in ovariectomized mice. This population is enriched for cells bearing the endothelial marker CD31 (10.3% of CD90(-) CD45(-) and 97.8% CD90(+) CD45(-) by flow cytometry). CD45(-) mTert-GFP(+) cells also immunostained for the endothelial marker von Willebrand factor. These results suggest that the endometrial epithelium and vasculature are foci of stem/progenitor activity and provide a system to investigate molecular mechanisms involved in endometrial regeneration and repair. LIMITATIONS, REASONS FOR CAUTION: The stem/progenitor activity of endometrial mTert-GFP(+) cells needs to be experimentally verified. WIDER IMPLICATIONS OF THE FINDINGS: The identification and characterization of mTert-expressing progenitor cells in the mouse will facilitate the identification of equivalent populations in the human endometrium that are likely to be involved in endometrial function, fertility and disease. LARGE-SCALE DATA: Not applicable. STUDY FUNDING AND COMPETING INTERESTS: This study was funded by National Health and Medical Research Council (NHMRC) of Australia grants (1085435, C.E.G., J.A.D.), 1021127 (C.E.G.), NHMRC Senior Research Fellowship (1042298, C.E.G.), the Victorian Infrastructure Support Program, U.S. National Institutes of Health grant R01 DK084056 (D.T.B.) and the Harvard Stem Cell Institute (D.T.B.). The authors have no conflicts of interest to declare.


Assuntos
Endométrio/metabolismo , Células Endoteliais/metabolismo , Células Epiteliais/metabolismo , Células-Tronco/metabolismo , Telomerase/genética , Animais , Biomarcadores/metabolismo , Proliferação de Células , Endométrio/citologia , Células Endoteliais/citologia , Células Epiteliais/citologia , Feminino , Citometria de Fluxo , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/metabolismo , Leucócitos/citologia , Leucócitos/metabolismo , Camundongos , Ovariectomia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Regiões Promotoras Genéticas , Células-Tronco/citologia , Telomerase/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
2.
Cureus ; 16(3): e56239, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618456

RESUMO

Tuberculosis (TB) is among the most predominant infectious illnesses in developing areas around the globe. As stated by the World Health Organization (WHO), the number of instances of drug-resistant tuberculosis (DR-TB) has increased lately. This case report describes the effective diagnosis and customized treatment for primary extra-pulmonary multidrug-resistant tubercular pleural effusion, a disease which is difficult to identify due to relatively low bacterial count as well as frequently negative staining on Ziehl Neelsen (ZN) for acid-fast bacilli (AFB). The bacteria causing multidrug-resistant tuberculosis (MDR-TB) is resistant to a minimum of two drugs, isoniazid and rifampicin, the most effective TB medications. We are going to present the case of a 60-year-old male who complained of breathlessness, cough, and loss of weight for one month and chest pain and fever for 12 days. The patient's pleural fluid examination was carried out, which showed exudative fluid (according to Light's criteria) with adenosine deaminase (ADA) positive. Cartridge-based nucleic acid amplification test (CBNAAT) and line probe assays (LPAs) were carried out, which suggested mycobacterium tuberculosis (MTB) with rifampicin and isoniazid resistance. The patient was started an oral regimen with bedaquiline in accordance with WHO standards, leading to significant improvement. This case reveals that to promptly diagnose and treat DR-TB, pleural effusions, and pleural biopsies need to be exposed early to investigations such as Xpert (MTB)/resistance to rifampicin assay, culturing, and genotype drug sensitivity testing (DST).

3.
Indian J Dent Res ; 33(3): 297-300, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36656192

RESUMO

Introduction: Early childhood caries (ECC), which results in rapid involvement and progression of several teeth, is a growing concern in preschool children. It directly affects a child's overall health and quality of life. Aim: To assess the prevalence and determinants of ECC among children enrolled in Anganwadi centres in Bhilai city of Chhattisgarh. Methodology: This descriptive cross-sectional study was conducted among 360 children enrolled in Anganwadi of Bhilai. An oral examination and findings were recorded in 'dmft' using the WHO oral health assessment form for children 2013. The mothers' knowledge, attitude, and practice were determined by a professionally administered 10-item pre-tested short questionnaire with Cronbach's alpha of 0.86. The data were compiled and analysed using Microsoft Excel vs. 2013 and Statistical Package of Social Science (IBM SPSS version 23; Chicago Inc., USA). Results: The prevalence of ECC was 25.83%, out of which 13.33% in boys and 12.50% in girls. Children of middle school-educated mothers have 35.48% ECC, followed by high school and primary school, that is, 24.73 and 23.66, respectively. Mothers who assisted the children in tooth brushing have less prevalence of ECC (8.15%) as compared to non-assisted (17.8%) (P = 0.044). Conclusion: Although mothers' knowledge was appreciable regarding reasons for tooth decay, still 1/4th of the children were found to be affected by ECC. This necessitates the importance of regular/periodic screening campaigns for the children, implementing institutional preventive programmes, and referral for children to secondary/tertiary healthcare centres.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Transversais , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Prevalência , Qualidade de Vida , Assistência Odontológica para Crianças
4.
Exp Neurol ; 308: 120-131, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30012511

RESUMO

INTRODUCTION: Preterm infants are at high risk for white matter injury and subsequent neurodevelopmental impairments. Mesenchymal stem/stromal cells (MSC) have anti-inflammatory/immunomodulatory actions and are of interest for neural repair in adults and newborns. This study examined the neuroprotective effects of allogeneic MSC, derived from preterm umbilical cord blood (UCB), in a preterm sheep model of white matter injury. METHODS: Quad-lineage differentiation, clonogenicity and self-renewal ability of UCB-derived MSC were confirmed. Chronically instrumented fetal sheep (0.7 gestation) received either 25 min hypoxia-ischemia (HI) to induce preterm brain injury, or sham-HI. Ten million MSC, or saline, were administered iv to fetuses at 12 h after HI. Fetal brains were collected 10d after HI for histopathology and immunocytochemistry. RESULTS: HI induced white matter injury, as indicated by a reduction in CNPase-positive myelin fiber density. HI also induced microglial activation (Iba-1) in the periventricular white matter and internal capsule (P < .05 vs control). MSC administration following HI preserved myelination (P < .05), modified microglial activation, and promoted macrophage migration (CD163) and cell proliferation (Ki-67) within cerebral white matter (P < .05). Cerebral CXCL10 concentration was increased following MSC administration (P < .05), which was likely associated with macrophage migration and cell proliferation within the preterm brain. Additionally, MSC administration reduced systemic pro-inflammatory cytokine TNFα at 3d post-HI (P < .05). CONCLUSIONS: UCB-derived MSC therapy preserved white matter brain structure following preterm HI, mediated by a suppression of microglial activation, promotion of macrophage migration and acceleration of self-repair within the preterm brain. UCB-derived MSC are neuroprotective, acting via peripheral and cerebral anti-inflammatory and immunomodulatory mechanisms.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Hipóxia-Isquemia Encefálica/patologia , Transplante de Células-Tronco Mesenquimais/métodos , Animais , Animais Recém-Nascidos , Lesões Encefálicas/etiologia , Lesões Encefálicas/patologia , Feminino , Gravidez , Nascimento Prematuro , Ovinos
5.
Curr Protoc Stem Cell Biol ; 44: 2A.11.1-2A.11.13, 2018 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29512129

RESUMO

Clinical hematopoietic stem/progenitor cell (HSPC) transplantation outcomes are strongly correlated with the number of cells infused. Hence, to generate sufficient HSPCs for transplantation, the best culture parameters for expansion are critical. It is generally assumed that the defined oxygen (O2 ) set for the incubator reflects the pericellular O2 to which cells are being exposed. Studies have shown that low O2 tension maintains an undifferentiated state, but the expansion rate may be constrained because of limited diffusion in a static culture system. A combination of low ambient O2 and dynamic culture conditions has been developed to increase the reconstituting capacity of human HSPCs. In this unit, the protocols for serum-free expansion of HSPCs at 5% and 20% O2 in static and dynamic nutrient flow mode are described. Finally, the impact of O2 tension on HSPC expansion in vitro by flow cytometry and colony forming assays and in vivo through engraftment using a murine model is assessed. © 2018 by John Wiley & Sons, Inc.


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Hematopoéticas/citologia , Oxigênio/farmacologia , Animais , Antígenos CD34/metabolismo , Proliferação de Células/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Sangue Fetal/citologia , Citometria de Fluxo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos
6.
Curr Protoc Stem Cell Biol ; 36: 1C.15.1-1C.15.16, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26840223

RESUMO

Umbilical cord blood (UCB) is one of the richest sources for hematopoietic stem/progenitor cells (HSPCs), with more than 3000 transplantations performed each year for the treatment of leukemia and other bone marrow, immunological, and hereditary diseases. However, transplantation of single cord blood units is mostly restricted to children, due to the limited number of HSPC per unit. This unit develops a method to increase the number of HSPCs in laboratory conditions by using cell-free matrices from bone marrow cells that mimic 'human-body-niche-like' conditions as biological scaffolds to support the ex vivo expansion of HSPCs. In this unit, we describe protocols for the isolation and characterization of HSPCs from UCB and their serum-free expansion on decellularized matrices. This method may also help to provide understanding of the biochemical organization of hematopoietic niches and lead to suggestions regarding the design of tissue engineering-based biomimetic scaffolds for HSPC expansion for clinical applications.


Assuntos
Técnicas de Cultura de Células/métodos , Matriz Extracelular/química , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Nicho de Células-Tronco , Alicerces Teciduais/química , Proliferação de Células , Células-Tronco Hematopoéticas/metabolismo , Humanos
7.
Stem Cells Dev ; 25(20): 1604-1613, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27539189

RESUMO

Oxygen levels are an important variable during the in vitro culture of stem cells. There has been increasing interest in the use of low oxygen to maximize proliferation and, in some cases, effect differentiation of stem cell populations. It is generally assumed that the defined pO2 in the incubator reflects the pO2 to which the stem cells are being exposed. However, we demonstrate that the pO2 experienced by cells in static culture can change dramatically during the course of culture as cell numbers increase and as the oxygen utilization by cells exceeds the diffusion of oxygen through the media. Dynamic culture (whereby the cell culture plate is in constant motion) largely eliminates this effect, and a combination of low ambient oxygen and dynamic culture results in a fourfold increase in reconstituting capacity of human hematopoietic stem cells compared with those cultured in static culture at ambient oxygen tension. Cells cultured dynamically at 5% oxygen exhibited the best expansion: 30-fold increase by flow cytometry, 120-fold increase by colony assay, and 11% of human CD45 engraftment in the bone marrow of NOD/SCID mice. To our knowledge, this is the first study to compare individual and combined effects of oxygen and static or dynamic culture on hematopoietic ex vivo expansion. Understanding and controlling the effective oxygen tension experienced by cells may be important in clinical stem cell expansion systems, and these results may have relevance to the interpretation of low oxygen culture studies.

8.
Curr Protoc Stem Cell Biol ; 28: 1C.15.1-1C.15.15, 2014 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-24510768

RESUMO

Umbilical cord blood (UCB) is one of the richest sources for hematopoietic stem/progenitor cells (HSPCs), with more than 3000 transplantations performed each year for the treatment of leukemia and other bone marrow, immunological, and hereditary diseases. However, transplantation of single cord blood units is mostly restricted to children, due to the limited number of HSPC per unit. This unit develops a method to increase the number of HSPCs in laboratory conditions by using cell-free matrices from bone marrow cells that mimic 'human-body niche-like' conditions as biological scaffolds to support the ex vivo expansion of HSPCs. In this unit, we describe protocols for the isolation and characterization of HSPCs from UCB and their serum-free expansion on decellularized matrices. This method may also help to provide understanding of the biochemical organization of hematopoietic niches and lead to suggestions regarding the design of tissue engineering-based biomimetic scaffolds for HSPC expansion for clinical applications.


Assuntos
Técnicas de Cultura de Células/métodos , Matriz Extracelular/metabolismo , Células-Tronco Hematopoéticas/citologia , Alicerces Teciduais/química , Antígenos CD34/metabolismo , Biomarcadores/metabolismo , Proliferação de Células , Separação Celular , Sangue Fetal/citologia , Humanos
9.
J Tissue Eng Regen Med ; 7(11): 871-83, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22511368

RESUMO

Lineage-specific expansion of haematopoietic stem/progenitor cells (HSPCs) from human umbilical cord blood (UCB) is desirable because of their several applications in translational medicine, e.g. treatment of cancer, bone marrow failure and immunodeficiencies. The current methods for HSPC expansion use either cellular feeder layers and/or soluble growth factors and selected matrix components coated on different surfaces. The use of cell-free extracellular matrices from bone marrow cells for this purpose has not previously been reported. We have prepared insoluble, cell-free matrices from a murine bone marrow stromal cell line (MS-5) grown under four different conditions, i.e. in presence or absence of osteogenic medium, each incubated under 5% and 20% O2 tensions. These acellular matrices were used as biological scaffolds for the lineage-specific expansion of magnetically sorted CD34⁺ cells and the results were evaluated by flow cytometry and colony-forming assays. We could get up to 80-fold expansion of some HSPCs on one of the matrices and our results indicated that oxygen tension played a significant role in determining the expansion capacity of the matrices. A comparative proteomic analysis of the matrices indicated differential expression of proteins, such as aldehyde dehydrogenase and gelsolin, which have previously been identified as playing a role in HSPC maintenance and expansion. Our approach may be of value in identifying factors relevant to tissue engineering-based ex vivo HSPC expansion, and it may also provide insights into the constitution of the niche in which these cells reside in the bone marrow.


Assuntos
Técnicas de Cultura de Células/métodos , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Alicerces Teciduais/química , Antígenos CD34/metabolismo , Biomarcadores/metabolismo , Linhagem Celular , Linhagem da Célula , Proliferação de Células , Separação Celular , Ensaio de Unidades Formadoras de Colônias , Eletroforese em Gel Bidimensional , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imunofenotipagem , Proteômica , Células Estromais/citologia
10.
Int Rev Cell Mol Biol ; 298: 95-133, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22878105

RESUMO

In adult mammals, maturation of blood and bone cells from their respective progenitors occurs in the bone marrow. The marrow region contains many progenitor and stem cell types that are confined by their biochemical and cellular microenvironments, referred to as stem cell niches. The unique properties of each niche assist the survival, proliferation, migration, and differentiation of that particular stem or progenitor cell type. Among the different niches of the bone marrow, our understanding of the osteohematopoietic niche is the most complete. Its properties, described in this chapter, are a model for studying adult stem cell differentiation, but a lot remains unknown. Our improved understanding of hematopoietic stem cell biology and its relationship with the properties of these niches are critical in the effective and safe use of these cells in regenerative medicine. Here, we review the current knowledge on the properties of these niches and suggest how the potential of hematopoietic progenitors can be utilized in regenerative medicine.


Assuntos
Células da Medula Óssea/citologia , Células-Tronco Hematopoéticas/citologia , Osteócitos/citologia , Nicho de Células-Tronco , Animais , Hematopoese , Humanos , Modelos Biológicos
11.
Bioinformation ; 4(9): 405-8, 2010 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-20975890

RESUMO

ATP-dependent Clp protease (ClpP) is a core unit of a major bacterial protease complex employing as a new attractive drug target for that isolates, which are resistant to antibiotics. Mycobacterium tuberculosis, a gram-positive bacterium, is one of the major causes of hospital acquired infections. ClpP in Mycobacterium tuberculosis is usually tightly regulated and strictly requires a member of the family of Clp-ATPase and often further accessory proteins for proteolytic activation. Inhibition of ClpP eliminates these safeguards and start proteolytic degradation. Such uncontrolled proteolysis leads to inhibition of bacterial cell division and eventually cell death. In order to inhibit Clp protease, at first three dimensional structure model of ClpP in Mycobacterium tuberculosis was determined by comparative homology modeling program MODELLER based on crystal structure of the proteolytic component of the caseinolytic Clp protease (ClpP) from E. coli as a template protein and has 55%sequence identity with ClpP protein. The computed model's energy was minimized and validated using PROCHECK to obtain a stable model structure and is submitted in Protein Model Database (PMDB-ID: PM0075741). Stable model was further used for virtual screening against marine derived bioactive compound database through molecular docking studies using AutoDock 3.05. The docked complexes were validated and enumerated based on the AutoDock Scoring function to pick out the best marine inhibitors based on docked Energy. Thus from the entire 186 Marine compounds which were Docked, we got best 5 of them with optimal docked Energy (Ara-A: -14.31 kcal/mol, Dysinosin C: - 14.90kcal/mol, Nagelamide A: -20.49 kcal/mol, Strobilin: -8.02 kcal/mol, Manoalide: -8.81 kcal/mol). Further the five best-docked complexes were analyzed through Python Molecular Viewer software for their interaction studies. Thus from the Complex scoring and binding ability its deciphered that these Marine compounds could be promising inhibitors for ClpP as Drug target yet pharmacological studies have to confirm it.

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