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1.
Int J Mol Sci ; 23(14)2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35886978

RESUMO

SOX2 is a recognized pluripotent transcription factor involved in stem cell homeostasis, self-renewal and reprogramming. It belongs to, one of the SRY-related HMG-box (SOX) family of transcription factors, taking part in the regulation of embryonic development and determination of cell fate. Among other functions, SOX2 promotes proliferation, survival, invasion, metastasis, cancer stemness, and drug resistance. SOX2 interacts with other transcription factors in multiple signaling pathways to control growth and survival. The aim of the study was to determine the effect of a parturient's age, umbilical cord blood pH and length of pregnancy on the quality of stem cells derived from Wharton's jelly (WJSC) by looking at birth weight and using SOX2 gene expression as a marker. Using qPCR the authors, evaluated the expression of SOX2 in WJSC acquired from the umbilical cords of 30 women right after the delivery. The results showed a significant correlation between the birth weight and the expression of SOX2 in WJSC in relation to maternal age, umbilical cord blood pH, and the length of pregnancy. The authors observed that the younger the woman and the lower the umbilical cord blood pH, the earlier the delivery occurs, the lower the birth weight and the higher SOX2 gene expression in WJSC. In research studies and clinical applications of regenerative medicine utilizing mesenchymal stem cells derived from Wharton's Jelly of the umbilical cord, assessment of maternal and embryonic factors influencing the quality of cells is critical.


Assuntos
Células-Tronco Mesenquimais , Fatores de Transcrição SOXB1 , Geleia de Wharton , Biomarcadores/metabolismo , Peso ao Nascer , Diferenciação Celular/fisiologia , Feminino , Expressão Gênica , Humanos , Recém-Nascido , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Gravidez , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Geleia de Wharton/citologia , Geleia de Wharton/metabolismo
2.
J Clin Med ; 11(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35743538

RESUMO

A growing body of evidence indicates a crucial role of miRNA regulatory function in a variety of mechanisms that contribute to the development of diseases. In our previous work, alterations in miRNA expression levels and targeted genes were shown in peripheral blood mononuclear cells (PBMCs) from patients with lower extremity artery disease (LEAD), abdominal aortic aneurysm (AAA), and chronic venous disease (CVD) in comparison with healthy controls. In this paper, previously obtained miRNA expression profiles were compared between the LEAD, AAA, and CVD groups to find either similarities or differences within the studied diseases. Differentially expressed miRNAs were identified using the DESeq2 method implemented in the R programming software. Pairwise comparisons (LEAD vs. AAA, LEAD vs. CVD, and AAA vs. CVD) were performed and revealed 10, 8, and 17 differentially expressed miRNA transcripts, respectively. The functional analysis of the obtained miRNAs was conducted using the miRNet 2.0 online tool and disclosed associations with inflammation and cellular differentiation, motility, and death. The miRNet 2.0 tool was also used to identify regulatory interactions between dysregulated miRNAs and target genes in patients with LEAD, AAA, and CVD. The presented research provides new information about similarities and differences in the miRNA-dependent regulatory mechanisms involved in the pathogenesis of LEAD, AAA, and CVD.

3.
J Appl Genet ; 63(3): 497-512, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35366714

RESUMO

Lower extremity artery disease (LEAD) is an underestimated chronic vascular disease caused by the formation of atherosclerotic plaques in the lower limb arteries. The pathological processes underlying this disease are regulated by many various factors, including microRNAs (miRNAs). miRNAs constitute a pool of small, non-coding RNAs with a gene expression modulatory function. In the presented study, differentially expressed miRNAs were identified in peripheral blood mononuclear cells from 18 patients with LEAD compared to 10 healthy volunteers using OpenArray RT-qPCR. Sixteen miRNAs were significantly differentially expressed in the LEAD group. Four out of them, hsa-miR-138-5p, -34a-3p, -34a-5p, and -766-3p, were consistent with a previous next-generation sequencing study. The in silico analysis performed for these four miRNAs showed associations with vascular smooth muscle cells differentiation, inflammation, and apoptosis, potentially resulting from modulation of genes involved in cell cycle, cellular adhesion, and Notch signaling. The presented study expands our knowledge on the role of miRNA in the pathology of LEAD, providing potential candidates for biomarkers of this disease.


Assuntos
Perfilação da Expressão Gênica , MicroRNAs , Artérias/metabolismo , Biomarcadores , Perfilação da Expressão Gênica/métodos , Humanos , Leucócitos Mononucleares/metabolismo , Extremidade Inferior , MicroRNAs/genética
4.
J Clin Med ; 11(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35329950

RESUMO

Lower extremity artery disease (LEAD) is an underdiagnosed and globally underestimated vascular disease caused by the progressive and chronic formation of atherosclerotic plaques in the arteries of the lower limbs. Much evidence indicates that the abnormal course of pathophysiological processes underlying LEAD development is associated with altered miRNA modulatory function. In the presented study, relationships between miRNA expression and clinical indicators of this disease (ABI, claudication distance, length of arterial occlusion, Rutherford category, and plaque localization) were identified. MiRNA expression profiles were obtained using next-generation sequencing in peripheral blood mononuclear cells (PBMCs) of 40 LEAD patients. Correlation analysis performed using the Spearman rank correlation test revealed miRNAs related to ABI, claudication distance, and length of arterial occlusion. In the DESeq2 analysis, five miRNAs were found to be dysregulated in patients with Rutherford category 3 compared to patients with Rutherford category 2. No miRNAs were found to be differentially expressed between patients with different plaque localizations. Functional analysis performed using the miRNet 2.0 website tool determined associations of selected miRNAs with processes underlying vascular pathology, such as vascular smooth muscle cell differentiation, endothelial cell apoptosis, response to hypoxia, inflammation, lipid metabolism, and circadian rhythm. The most enriched functional terms for genes targeted by associated miRNAs were linked to regulation of the cell cycle, regulation of the transcription process, and nuclear cellular compartment. In conclusion, dysregulations of miRNA expression in PBMCs of patients with LEAD are indicative of the disease and could potentially be used in the prediction of LEAD progression.

5.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614026

RESUMO

Vascular diseases are one of the most common causes of death and morbidity. Lower extremity artery disease (LEAD), abdominal aortic aneurysm (AAA) and chronic venous disease (CVD) belong to this group of conditions and exhibit various presentations and courses; thus, there is an urgent need for revealing new biomarkers for monitoring and potential treatment. Next-generation sequencing of mRNA allows rapid and detailed transcriptome analysis, allowing us to pinpoint the most pronounced differences between the mRNA expression profiles of vascular disease patients. Comparison of expression data of 519 DNA-repair-related genes obtained from mRNA next-generation sequencing revealed significant transcriptomic marks characterizing AAA, CVD and LEAD. Statistical, gene set enrichment analysis (GSEA), gene ontology (GO) and literature analyses were applied and highlighted many DNA repair and accompanying processes, such as cohesin functions, oxidative stress, homologous recombination, ubiquitin turnover, chromatin remodelling and DNA double-strand break repair. Surprisingly, obtained data suggest the contribution of genes engaged in the regulatory function of DNA repair as a key component that could be used to distinguish between analyzed conditions. DNA repair-related genes depicted in the presented study as dysregulated in AAA, CVD and LEAD could be utilized in the design of new biomarkers or therapies associated with these diseases.


Assuntos
Aneurisma da Aorta Abdominal , Transcriptoma , Humanos , Aneurisma da Aorta Abdominal/genética , Perfilação da Expressão Gênica , Artérias , Biomarcadores , Extremidade Inferior/irrigação sanguínea , Sequenciamento de Nucleotídeos em Larga Escala , Dano ao DNA
6.
Int J Mol Sci ; 22(6)2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33801150

RESUMO

Several human tissues are investigated in studies of molecular biomarkers associated with diseases development. Special attention is focused on the blood and its components due to combining abundant information about systemic responses to pathological processes as well as high accessibility. In the current study, transcriptome profiles of peripheral blood mononuclear cells (PBMCs) were used to compare differentially expressed genes between patients with lower extremities arterial disease (LEAD), abdominal aortic aneurysm (AAA) and chronic venous disease (CVD). Gene expression patterns were generated using the Ion S5XL next-generation sequencing platform and were analyzed using DESeq2 and UVE-PLS methods implemented in R programming software. In direct pairwise analysis, 21, 58 and 10 differentially expressed genes were selected from the comparison of LEAD vs. AAA, LEAD vs. CVD and AAA vs. CVD patient groups, respectively. Relationships between expression of dysregulated genes and age, body mass index, creatinine levels, hypertension and medication were identified using Spearman rank correlation test and two-sided Mann-Whitney U test. The functional analysis, performed using DAVID website tool, provides potential implications of selected genes in pathological processes underlying diseases studied. Presented research provides new insight into differences of pathogenesis in LEAD, AAA and CVD, and selected genes could be considered as potential candidates for biomarkers useful in diagnosis and differentiation of studied diseases.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/genética , Perfilação da Expressão Gênica , Leucócitos Mononucleares/metabolismo , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/genética , Transcriptoma , Idoso , Biomarcadores , Estudos de Casos e Controles , Comorbidade , Biologia Computacional , Diagnóstico Diferencial , Feminino , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Veias
7.
J Clin Med ; 9(6)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599769

RESUMO

Abdominal artery aneurysm (AAA) refers to abdominal aortic dilatation of 3 cm or greater. AAA is frequently underdiagnosed due to often asymptomatic character of the disease, leading to elevated mortality due to aneurysm rupture. MiRNA constitute a pool of small RNAs controlling gene expression and is involved in many pathologic conditions in human. Targeted panel detecting altered expression of miRNA and genes involved in AAA would improve early diagnosis of this disease. In the presented study, we selected and analyzed miRNA and gene expression signatures in AAA patients. Next, generation sequencing was applied to obtain miRNA and gene-wide expression profiles from peripheral blood mononuclear cells in individuals with AAA and healthy controls. Differential expression analysis was performed using DESeq2 and uninformative variable elimination by partial least squares (UVE-PLS) methods. A total of 31 miRNAs and 51 genes were selected as the most promising biomarkers of AAA. Receiver operating characteristics (ROC) analysis showed good diagnostic ability of proposed biomarkers. Genes regulated by selected miRNAs were determined in silico and associated with functional terms closely related to cardiovascular and neurological diseases. Proposed biomarkers may be used for new diagnostic and therapeutic approaches in management of AAA. The findings will also contribute to the pool of knowledge about miRNA-dependent regulatory mechanisms involved in pathology of that disease.

8.
J Clin Med ; 9(5)2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344947

RESUMO

Chronic venous disease (CVD) is a vascular disease of lower limbs with high prevalence worldwide. Pathologic features include varicose veins, venous valves dysfunction and skin ulceration resulting from dysfunction of cell proliferation, apoptosis and angiogenesis. These processes are partly regulated by microRNA (miRNA)-dependent modulation of gene expression, pointing to miRNA as a potentially important target in diagnosis and therapy of CVD progression. The aim of the study was to analyze alterations of miRNA and gene expression in CVD, as well as to identify miRNA-mediated changes in gene expression and their potential link to CVD development. Using next generation sequencing, miRNA and gene expression profiles in peripheral blood mononuclear cells of subjects with CVD in relation to healthy controls were studied. Thirty-one miRNAs and 62 genes were recognized as potential biomarkers of CVD using DESeq2, Uninformative Variable Elimination by Partial Least Squares (UVE-PLS) and ROC (Receiver Operating Characteristics) methods. Regulatory interactions between potential biomarker miRNAs and genes were projected. Functional analysis of microRNA-regulated genes revealed terms closely related to cardiovascular diseases and risk factors. The study shed new light on miRNA-dependent regulatory mechanisms involved in the pathology of CVD. MicroRNAs and genes proposed as CVD biomarkers may be used to develop new diagnostic and therapeutic methods.

9.
Ann Agric Environ Med ; 27(1): 113-122, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32208589

RESUMO

INTRODUCTION AND OBJECTIVE: Using the concepts of Ulrich's theory of supportive design and Malkin's healing environment, an eye tracking experiment was designed in order to measure respondents' reactions while looking at visualisations of various interiors, with the aim of verifying whether certain parameters of an interior are related to emotional reactions in terms of positive stimulation, and the sense of security and comfort. MATERIAL AND METHODS: 12 boards were designed, incorporating standard features of an interior, i.e. (1) proportions, (2) lighting, (3) colour scheme of a room, as well as (4) the colours and spatial arrangement of furnishings. Respondents' reactions were recorded with an eye tracker Tobii TX300 and supplemented by self-descriptions of emotional reactions. RESULTS: The results showed that the varying spatial and colour arrangements presented in the interior visualisations provoked different emotional responses, confirmed by pupil reaction parameters, as measured by the eye tracking device. CONCLUSIONS: Architectural space can have a diverse emotional significance and impact on an individual's emotional state. This is an important conclusion from the point of view of optimising and creating the so-called supportive and healing environment. The results have implications for the interpretation of the pupil diameter as an index of emotional reactions to different architectural space visualisations. Testing the eye tracker as a method helpful in diagnosing the emotional reactions to features of the interior is justified, and can provide an effective tool for early diagnosis of the impact of architectural space on the well-being of individuals. It can also be a good form of testing the emotional significance of architectural designs before they are implemented.


Assuntos
Emoções/fisiologia , Decoração de Interiores e Mobiliário , Pupila/fisiologia , Adulto , Cor , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia
10.
Front Genet ; 10: 1200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827490

RESUMO

Atherosclerosis and its comorbidities are the major contributors to the global burden of death worldwide. Lower extremities arterial disease (LEAD) is a common manifestation of atherosclerotic disease of arteries of lower extremities. MicroRNAs belong to epigenetic factors that regulate gene expression and have not yet been extensively studied in LEAD. We aimed to indicate the most promising microRNA and gene expression signatures of LEAD, to identify interactions between microRNA and genes and to describe potential effect of modulated gene expression. High-throughput sequencing was employed to examine microRNAome and transcriptome of peripheral blood mononuclear cells of patients with LEAD, in relation to controls. Statistical significance of microRNAs and genes analysis results was evaluated using DESeq2 and uninformative variable elimination by partial least squares methods. Altered expression of 26 microRNAs (hsa-let-7f-1-3p, hsa-miR-34a-5p, -122-5p, -3591-3p, -34a-3p, -1261, -21-5p, -15a-5p, -548d-5p, -34b-5p, -424-3p, -548aa, -548t-3p, -4423-3p, -196a-5p, -330-3p, -766-3p, -30e-3p, -125b-5p, -1301-3p, -3184-5p, -423-3p, -339-3p, -138-5p, -99a-3p, and -6087) and 14 genes (AK5, CD248, CDS2, FAM129A, FBLN2, GGT1, NOG, NRCAM, PDE7A, RP11-545E17.3, SLC12A2, SLC16A10, SLC4A10, and ZSCAN18) were the most significantly differentially expressed in LEAD group compared to controls. Discriminative value of revealed microRNAs and genes were confirmed by receiver operating characteristic analysis. Dysregulations of 26 microRNAs and 14 genes were used to propose novel biomarkers of LEAD. Regulatory interactions between biomarker microRNAs and genes were studied in silico using R multiMiR package. Functional analysis of genes modulated by proposed biomarker microRNAs was performed using DAVID 6.8 tools and revealed terms closely related to atherosclerosis and, interestingly, the processes involving nervous system. The study provides new insight into microRNA-dependent regulatory mechanisms involved in pathology of LEAD. Proposed microRNA and gene biomarkers of LEAD may provide new diagnostic and therapeutic opportunities.

11.
Molecules ; 24(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108853

RESUMO

Background: The natural compounds have been researched extensively as an alternative to the conventional chemotherapy and radiation. Stilbene derivatives appear as a group of therapeutics which deserves special attention. The present study was designed to analyze the effects of stilbene derivatives on drug resistant human leukemic cells. The aim of this work was to evaluate the apoptotic effect of stilbene derivatives in various concentrations on leukemic cells (LC) with and without resistant phenotype. Methods: Human acute promyelocytic leukemia (APL) cell lines (HL60, HL60/MX1, HL60/MX2) and acute lymphoblastic leukemia (ALL) cell lines (CEM/C1, CCRF-CEM) were studied. T-resveratrol, piceatannol, rhaponticin, deoxyrhaponticin, pterostilbene were used to stimulate apoptosis. Mitoxantrone (MIT) was applied to induce drug resistance. Results: t-Resveratrol (RES), deoxyrhaponticin (D-RHAP), rhaponticin (RHAP), pterostilbene (PTER), and piceatannol (PIC) influenced viability and induced apoptosis in all investigated cell lines. Conclusions: Our results confirmed that RES, PIC, RHAP, D-RHAP, and PTER are essential therapeutic compounds with anticancer activity exhibited by induction of apoptosis in leukemic cells with and without resistant phenotype. Stilbene-induced apoptosis in HL60/MX1, HL60/MX2, CEM/C1, and CCRF-CEM leukemia cell lines have been presented in very few studies so far and our research is an important contribution to the investigation of these substances.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estilbenos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Citometria de Fluxo , Células HL-60 , Humanos , Mitoxantrona , Resveratrol/farmacologia
12.
Stem Cell Rev Rep ; 13(4): 465-481, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28364326

RESUMO

Outlined are advances of cytometry applications to identify and sort stem cells, of laser scanning cytometry and ImageStream imaging instrumentation to further analyze morphometry of these cells, and of mass cytometry to classify a multitude of cellular markers in large cell populations. Reviewed are different types of stem cells, including potential candidates for cancer stem cells, with respect to their "stemness", and other characteristics. Appraised is further progress in identification and isolation of the "very small embryonic-like stem cells" (VSELs) and their autogenous transplantation for tissue repair and geroprotection. Also assessed is a function of hyaluronic acid, the major stem cells niche component, as a guardian and controller of stem cells. Briefly appraised are recent advances and challenges in the application of stem cells in regenerative medicine and oncology and their future role in different disciplines of medicine, including geriatrics.


Assuntos
Citometria de Fluxo , Nicho de Células-Tronco , Células-Tronco/metabolismo , Animais , Humanos
13.
Med Sci Monit ; 23: 1886-1895, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28422936

RESUMO

BACKGROUND Mesenchymal stromal cells, MSCs, show expression of specific antigens on their surface. The aim of the study is to assess the phenotype of stem cells like isolated from the umbilical cord with respect to the presence of surface antigens CD34, CD90, and CD105 and differences in the expression of surface antigens in cells isolated from freshly sampled material in comparison with the phenotype of cells from in vitro culture. MATERIAL AND METHODS Stem cells collected from the umbilical cord from healthy patients and then cultured in vitro. To assess the phenotype of stem cells, cytometric analysis was carried out. To assess the phenotype of cells we used fluorescently labelled monoclonal antibodies: APC Mouse anti-human CD34, PC5 Mouse anti-human CD90 and PE Mouse anti-human CD105. RESULTS In the case of cells from the umbilical cord and then cultured in vitro for the period of 10-14 days CD34 expression is lower (69,5%) in comparison with the group of cells not cultured. Not cultured cells were demonstrated 37% of cells co-expression of antigens CD34 and CD105, over 21% of CD34/CD90 cells and over 24% of CD105/CD90. Cultured cells group was showed higher percentage of CD90, CD105, CD34/CD105, CD34/CD90, CD105/CD90 in comparison with not cultured cells. CONCLUSIONS Our reults suggested that adherent cells population from umbilical cord, demonstrate CD34 expression In vivo. Moreover, the phenotype of MSCs, mainly in the context of CD34 expression, may vary depending on the place of collection of cells and the length of growing the cell culture.


Assuntos
Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Cordão Umbilical/citologia , Antígenos CD/metabolismo , Adesão Celular/genética , Adesão Celular/fisiologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Proliferação de Células , Separação Celular , Células Cultivadas , Sangue Fetal/citologia , Citometria de Fluxo , Humanos , Células-Tronco Mesenquimais/metabolismo , Fenótipo , Células-Tronco
14.
Oxid Med Cell Longev ; 2017: 5647281, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29387293

RESUMO

The presence of multidrug resistance (MDR) in tumor cells is considered as the major cause of failure of cancer chemotherapy. The mechanism responsible for the phenomenon of multidrug resistance is explained, among others, as overexpression of membrane transporters primarily from the ABC family which actively remove cytostatics from the tumor cell. The effect of 20 coumarin derivatives on the cytotoxicity and expression of MDR1, MRP1, BCRP, and LRP genes (encoding proteins responsible for multidrug resistance) in cancer cells was analyzed in the study. The aim of this research included determination of IC10 and IC50 values of selected coumarin derivatives in the presence and absence of mitoxantrone in leukemia cells and analysis of changes in the expression of genes involved in multidrug resistance: MDR1, MRP, LRP, and BCRP after 24-hour exposure of the investigated cell lines to selected coumarins in the presence and absence of mitoxantrone in IC10 and IC50 concentrations. The designed research was conducted on 5 cell lines derived from the human hematopoietic system: CCRF/CEM, CEM/C1, HL-60, HL-60/MX1, and HL-60/MX2. Cell lines CEM/C1, HL-60/MX1, and HL-60/MX2 exhibit a multidrug resistance phenotype.


Assuntos
Cumarínicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia/metabolismo , Proteínas de Neoplasias/biossíntese , Células HL-60 , Humanos , Leucemia/tratamento farmacológico
15.
PLoS One ; 11(1): e0147637, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26808268

RESUMO

Microbe-derived lactic acid protects women from pathogens in their genital tract. The purpose of this study was to determine lactic acid susceptibility of Neisseria gonorrhoeae, and identify potential acid resistance mechanisms present in this pathogen. Tested in vitro, lactic acid killed all 10 gonococcal strains analyzed in a low pH-dependent manner. Full inactivation occurred at pH 4.5. At low pH, lactic acid treatment resulted in the entry of the DNA-binding fluorochrome propidium iodide into the microbial cells, suggesting that hydrogen ions from lactic acid compromise the integrity of the bacterial cell wall/membrane. Most likely, hydrogen ions also inactivate intracellular proteins since arginine rendered significant protection against lactic acid presumably through action of the gonococcal arginine decarboxylase, an enzyme located in the bacterial cytoplasm. Surprisingly, arginine also lessened lactic acid-mediated cell wall/membrane disruption. This effect is probably mediated by agmatine, a triamine product of arginine decarboxylase, since agmatine demonstrated a stronger protective effect on GC than arginine at equal molar concentration. In addition to agmatine, diamines cadaverine and putrescine, which are generated by bacterial vaginosis-associated microbes, also induced significant resistance to lactic acid-mediated GC killing and cell wall/membrane disruption. These findings suggest that the arginine-rich semen protects gonococci through both neutralization-dependent and independent mechanisms, whereas polyamine-induced acid resistance contributes to the increased risk of gonorrhea in women with bacterial vaginosis.


Assuntos
Arginina/fisiologia , Poliaminas Biogênicas/fisiologia , Ácido Láctico/metabolismo , Neisseria gonorrhoeae/patogenicidade , Concentração de Íons de Hidrogênio , Propídio/metabolismo
16.
Methods ; 44(3): 250-4, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18314056

RESUMO

Activation of endonucleases that cleave chromosomal DNA preferentially at internucleosomal sections is a hallmark of apoptosis. DNA fragmentation revealed by the presence of a multitude of DNA strand breaks, therefore, is considered to be the gold standard for identification apoptotic cells. Several variants of the methodology that is based on fluorochrome-labeling of 3'-OH termini of DNA strand breaks in situ with the use of exogenous terminal deoxynucleotidyl transferase (TdT), commonly defined as the TUNEL assay, have been developed by us. This Chapter describes the variant based on strand breaks labeling with Br-dUTP that is subsequently detected immunocytochemically with Br-dUAb. Compared with other TUNEL variants the Br-dU-labeling assay offers the greatest sensitivity in detecting DNA breaks. Described also are modifications of the protocol that allow one to use other than Br-dUTP fluorochrome-tagged deoxynucleotides to label DNA breaks. Concurrent staining of DNA with propidium or 4',6-diamidino-2-phenylindole (DAPI) and multiparameter analysis of cells by flow- or laser scanning cytometry enables one to correlate induction of apoptosis with the cell cycle phase.


Assuntos
Apoptose , Citometria de Fluxo/métodos , Marcação In Situ das Extremidades Cortadas/métodos , Quebras de DNA , Humanos , Microscopia de Fluorescência , Kit de Reagentes para Diagnóstico
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