Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Mais filtros

Bases de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Clin Exp Hypertens ; 45(1): 2177667, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36809885

RESUMO

BACKGROUND: Hypertensive intracerebral hemorrhage (HICH) is a life-threatening disease and lacks effective treatments. Previous studies have confirmed that metabolic profiles altered after ischemic stroke, but how brain metabolism changes after HICH was unclear. This study aimed to explore the metabolic profiles after HICH and the therapeutic effects of soyasaponin I on HICH. METHODS: HICH model was established first. Hematoxylin and eosin staining was used to estimate the pathological changes after HICH. Western blot and Evans blue extravasation assay were applied to determine the integrity of the blood-brain barrier (BBB). Enzyme-linked immunosorbent assay was used to detect the activation of the renin-angiotensin-aldosterone system (RAAS). Next, liquid chromatography-mass spectrometry-untargeted metabolomics was utilized to analyze the metabolic profiles of brain tissues after HICH. Finally, soyasaponin I was administered to HICH rats, and the severity of HICH and activation of the RAAS were further assessed. RESULTS: We successfully constructed HICH model. HICH significantly impaired BBB integrity and activated RAAS. HICH increased PE(14:0/24:1(15Z)), arachidonoyl serinol, PS(18:0/22:6(4Z, 7Z, 10Z, 13Z, 16Z, and 19Z)), PS(20:1(11Z)/20:5(5Z, 8Z, 11Z, 14Z, and 17Z)), glucose 1-phosphate, etc., in the brain, whereas decreased creatine, tripamide, D-N-(carboxyacetyl)alanine, N-acetylaspartate, N-acetylaspartylglutamic acid, and so on in the hemorrhagic hemisphere. Cerebral soyasaponin I was found to be downregulated after HICH and supplementation of soyasaponin I inactivated the RAAS and alleviated HICH. CONCLUSION: The metabolic profiles of the brains changed after HICH. Soyasaponin I alleviated HICH via inhibiting the RAAS and may serve as an effective drug for the treatment of HICH in the future.


Assuntos
Hemorragia Intracraniana Hipertensiva , Ácido Oleanólico , Saponinas , Ratos , Animais , Sistema Renina-Angiotensina
2.
Cancer Cell Int ; 22(1): 32, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042538

RESUMO

BACKGROUND: Glioblastoma is one of the most common fatal intracranial malignancies. Lysine-specific demethylase 1 (LSD1) reportedly has therapeutic effects on a variety of tumors. This study explored the therapeutic effect of LSD1 inhibition on glioblastoma cell lines and the possible underlying mechanisms. METHODS: The MTT assay was utilized to screen for the sensitivity of U87, U251 and T98G cells to 4, 5-dimethoxycarrageenin-6-one. qRT-PCR and western blot were used to measure the proliferation, apoptosis, and pyroptosis signaling pathway expression to observe the effect of LSD1 inhibition on U251 and T98G cells. Flow cytometry, immunofluorescence, immunohistochemistry, wound scratch, clone formation, and TUNEL assay were used to analyze the effects of 4, 5-dimethoxycanthin-6-one on glioblastoma cells. The effect of 4, 5-dimethoxycanthin-6-one was examined in vivo in BALB/c nude mice injected with U251 cells. HE staining was used to detect the histopathology of the tumor. RESULTS: LSD1 specifically catalyzes the demethylation of monomethylated and demethylated histone H3 lysine at position 4 (h3k4me1, h3k4me2, h3k4me3) and lysine at position 9 (h3k9me1). This regulated the transcriptional activity of proliferation, apoptosis, and pyroptosis signaling pathway genes. In vitro, the proliferation of glioblastoma cells was decreased in the 4, 5-dimethoxycanthin-6-one group. The expression of Caspase1 in glioblastoma cells treated with 4, 5-dimethoxycanthin-6-one increased, and the number of apoptotic cells increased. The tumor volume of mice injected with 4, 5-dimethoxycanthin-6-one decreased significantly. CONCLUSION: 4, 5-Dimethoxycanthin-6-one could act as a novel inhibitor of LSD1 to regulate glioblastoma, which could inhibit the proliferation of U251 and T98G cells and induce their apoptosis and pyroptosis. It is a potential drug for the treatment of glioblastoma.

3.
J Appl Microbiol ; 133(2): 972-986, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35560738

RESUMO

AIMS: In recent years, the incidence rate of hypertensive intracerebral haemorrhage (HICH) has been increasing, accompanied by high mortality and morbidity, which has brought a heavy burden to the social economy. However, the pathogenesis of HICH is still unclear. This study intends to explore the mechanism of gut microbiota metabolism and inflammation in the process of HICH to provide a theoretical basis for the diagnosis and treatment of HICH. METHODS AND RESULTS: HE staining showed that the brain tissues of model group had obvious oedema injury, which indicated that the HICH model was successfully constructed. ELISA analysis showed that IL-1ß and TNF-α levels in blood and brain tissues were significantly increased, and IL-10 level was significantly decreased in blood. IHC analysis showed that microglia and macrophages were activated in the model group. 16S rRNA sequence showed that the diversity of gut microbiota in HICH patients decreased. Also, the microbiota belonging to Firmicutes, Proteobacteria and Verrucomicrobia changed significantly. LC-MS/MS analysis showed that the metabolic phenotype of HICH patients changed. Also, the 3,7-dimethyluric acid- and 7-methylxanthine-related metabolic pathways of caffeine metabolism pathways were downregulated in patients with HICH. Bacteroides was negatively correlated with the IL-1ß and TNF-α levels. Blautia was negatively correlated with the IL-1ß and TNF-α levels, and positively correlated with the IL-10 level. Akkermansia was negatively correlated with the 3,7-dimethyluric acid and 7-methylxanthine. CONCLUSION: Our study suggested that HICH was accompanied by the increased inflammation marker levels in peripheral blood and brain, decreased gut microbiota diversity, altered gut metabolic phenotype and downregulation of caffeine metabolism pathway. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study reported that HICH accompanied by the increased inflammation, decreased gut microbiota diversity and altered gut metabolic phenotype. Due to the number of patients, this work was a pilot study.


Assuntos
Microbioma Gastrointestinal , Hemorragia Intracraniana Hipertensiva , Cafeína/farmacologia , Cromatografia Líquida , Microbioma Gastrointestinal/genética , Humanos , Inflamação , Interleucina-10 , Projetos Piloto , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem , Fator de Necrose Tumoral alfa
4.
Phys Rev E ; 108(1-1): 014205, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37583163

RESUMO

Over the past decade, dynamic schemes have been proposed for the use of bistable systems in the design of logic devices. A bistable system in a noisy background can operate as a reliable logic gate in a moderate noise level, which is called a logical stochastic resonance (LSR). In this paper, we theoretically explore the emergence of LSR in general bistable systems and identify the dynamical mechanisms of LSR. The timescale relationship between the measured time and the mean first-pass time of two-state transitions is a key condition in determining whether the system is reliable. Furthermore, we demonstrate that the stability of the logic operation can be significantly improved by choosing the appropriate filtering method. Low-pass filtered noise-driven systems are more stable than Gaussian white noise. However, band-pass and high-pass filtered noise are harmful to the stability of the system due to the filtering of low-frequency components. Our theoretical and numerical simulation results offer perspectives for the development of logic devices.

5.
Artigo em Inglês | MEDLINE | ID: mdl-23258991

RESUMO

The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4) and control points after acupuncturing Quchi (LI11). Thirty healthy volunteers (mean age 31.6 ± 8.7 years) received deqi acupuncture on Quchi (LI11, right side), and simultaneously changes in microvascular perfusion of Sanjian (LI3), Hegu (LI4), Yangxi (LI5), and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4) being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity.

6.
Artigo em Zh | MEDLINE | ID: mdl-23256997

RESUMO

OBJECTIVE: To observe the T cell subsets and blood cells in the peripheral blood of workers exposed to low levels of benzene for one year, and to investigate the relationship between T cell function impairment and benzene-induced hematopoietic injury after benzene exposure. METHODS: Eighty-eight workers (58 males and 30 females, aged 18 ∼ 22 years) who just began to work in the workshop of a paint factory with exposure to benzene in Guangzhou, China were assigned to experimental group, and 88 workers (58 males and 30 females, aged 18 ∼ 25 years) who worked in the workshop without exposure to benzene were selected as controls. The blood samples of the workers were examined once every 4 months to measure the percentages of peripheral T cell subsets and peripheral blood cell counts in the one-year study. The benzene concentrations at operation points were also measured. RESULTS: The peripheral blood cell counts in the benzene-exposed workers had no significant changes in the first and second examinations; the white blood cell (WBC) counts in the experimental group in the third and fourth examinations were significantly lower than that in the control group [(6.4 ± 3.0)×10(9)/L and (6.3 ± 2.7)×10(9)/L vs (7.3 ± 3.0)×10(9)/L, P < 0.05], and the platelet (PLT) count in the experimental group in the fourth examination was also significantly lower than that in the control group[(179 ± 74)×10(9)/L vs (189 ± 70)×10(9)/L, P < 0.05]. Compared with those in the control group (CD4+: 54.29 ± 12.78%, CD8+: 37.25 ± 12.30%), the percentage of CD3+ T cells in the experimental group increased in the third examination; the percentage of CD4+ T cells in the experimental group decreased continuously in the second, third, and fourth examinations (50.77 ± 11.05%, 45.40 ± 9.41%, and 41.27 ± 10.62%), while the percentage of CD8+ T cells in the experimental group kept increasing (46.07 ± 10.18%, 50.36 ± 10.62%, and 56.40 ± 9.41%) (P < 0.05). CONCLUSION: The change in T cell subsets precedes that in the blood system in the workers exposed to low levels of benzene.


Assuntos
Benzeno/efeitos adversos , Exposição Ocupacional/efeitos adversos , Subpopulações de Linfócitos T/citologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Contagem de Linfócitos , Masculino , Adulto Jovem
7.
Biophys Chem ; 125(1): 201-12, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16952419

RESUMO

Based on a model of intracellular calcium (Ca(2+)) oscillation with self-modulation of inositol 1,4,5-trisphosphate signal, the mesoscopic stochastic differential equations for the intracellular Ca(2+) oscillations are theoretically derived by using the chemical Langevin equation method. The effects of the finite biochemical reaction molecule number on both simple and complex cytosolic Ca(2+) oscillations are numerically studied. In the case of simple intracellular Ca(2+) oscillation, it is found that, with the increase of molecule number, the coherence resonance or autonomous resonance phenomena can occur for some external stimulation parameter values. In the cases of complex cytosolic Ca(2+) oscillations, each extremum of concentration of cytosolic Ca(2+) oscillations corresponds to a peak in the histogram of Ca(2+) concentration, and the most probability appeared during the bursting plateau level for bursting, but at the largest minimum of Ca(2+) concentration for chaos. For quasi-periodicity, however, there are only two peaks in the histogram of Ca(2+) concentration, and the most probability is located at low concentration state.


Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Citosol/metabolismo , Inositol 1,4,5-Trifosfato/fisiologia , Modelos Biológicos , Oscilometria , Processos Estocásticos
8.
Artigo em Zh | MEDLINE | ID: mdl-17456402

RESUMO

OBJECTIVE: To investigate the levels of T cell receptor rearrangement excision DNA circles (TRECs) within peripheral blood from workers exposed to lead, and thereby to evaluate the number of naive T cells and recent thymic output function. METHODS: Quantitative detection of TRECs in peripheral blood mononuclear cells (PBMNC) from 10 cases of workers exposed to lead was performed by real time PCR analysis. 11 workers without exposure to lead served as unexposed controls. In addition, the relationship between TRECs, age, length of service, blood lead, urea lead, blood ZPP and urea delta-ALA was investigated. RESULTS: The mean value of TRECs in workers exposed to lead was (2.44 +/- 1.87)/1000 PBMC, significantly under (5.60 +/- 3.96)/1000 PBMC in unexposed controls. A significant negative correlation was found between the TRECs and urea-ALA. But there was no significant correlation between them after controlling for blood lead, urea lead. CONCLUSION: Lead exposure may damage thymic output naive T cells function. Furthermore, low-level exposure to lead may damage immune system and earlier than expected.


Assuntos
DNA/efeitos dos fármacos , Chumbo/toxicidade , Exposição Ocupacional/efeitos adversos , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/efeitos dos fármacos , Timo/imunologia , Adulto , Rearranjo Gênico do Linfócito T/efeitos dos fármacos , Humanos , Leucócitos Mononucleares , Masculino , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia
9.
Artigo em Zh | MEDLINE | ID: mdl-17535656

RESUMO

OBJECTIVE: To observe the changes of T-lymphocyte subsets in workers with long-term benzene exposure, and further understand the benzene's lymphotoxicity. METHODS: Blood was sampled from 44 patients with chronic benzene poisoning of different degrees, (mild 22 patients, moderate 14, severe 8) respectively. Twenty-two health benzene exposed workers, and 94 health unexposed workers served as normal control. A total of the phenotype (CD4, CD8) of T lymphocyte in peripheral blood was analyzed by indirect immunofluorescence assay. RESULTS: Lymphocyte subset analysis showed significantly decreased CD4(+) T lymphocytes, CD4(+)/CD8(+) ratio, except CD8(+) T lymphocytes in benzene exposed groups (P<0.05). Among the four benzene-exposed groups, CD4(+) T lymphocytes and CD4(+)/CD8(+) ratio showed no difference (P>0.05). CONCLUSION: The primary changes of T-lymphocyte subsets in workers following benzene long-term exposure are the decrease of CD4(+)%, but the changes are not correlated with haematopoietic injury.


Assuntos
Benzeno/intoxicação , Exposição Ocupacional/efeitos adversos , Subpopulações de Linfócitos T/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Artigo em Zh | MEDLINE | ID: mdl-18070497

RESUMO

OBJECTIVE: To observe the distribution of TCR V alpha gene repertoire and clonal expansion in peripheral blood mononuclear cells from 9 donors and 16 workers exposed to benzene. METHODS: Complementarity determining region 3 (CDR3) of TCR V alpha subfamily genes were amplified using RT-PCR. The PCR products were further analyzed by genescan to evaluate clonality of T cells. RESULTS: Almost all of 29 V alpha subfamily could be detected in 9 donors. 1 approximately 11 V alpha subfamilies were identified in all but one of the workers studied. The most frequently expressed V alpha subfamily were V alpha 3, V alpha 12 and V alpha 19 (68.8%), V alpha 14 (56.3%), with a lower expression rate found in V alpha 5, V alpha 15, V alpha 16, V alpha 22, V alpha 23 and V alpha 24 (6.3%). Clonal expansion T cells in one or more V alpha subfamily were found in 12 out of all workers studied, including oligoclonal, oligoclonal trend and biclonal patterns. The frequency of clonal expansion T cells in V alpha 12, V alpha 14 and V alpha 19 subfamilies were higher than others. CONCLUSION: Skewed distribution and clonal expansion of TCR V alpha subfamily T cells could be found in workers exposed to benzene. V alpha 12, V alpha 14 and V alpha 19 subfamilies may be highly sensitive to benzene exposed. This is the first report of clonal expansion TCR V alpha T cells in the benzene-exposed group. The bias pattern of TCR V alpha T cells may be due to the immune cytotoxicity from benzene. However, whether the oligoclonality in some V alpha subfamilies reflect the phenomenon of clone absence or may be a response clone to benzene-related impairment during exposed to benzene, remains an open question.


Assuntos
Benzeno/intoxicação , Regiões Determinantes de Complementaridade/genética , Genes Codificadores da Cadeia alfa de Receptores de Linfócitos T/genética , Doenças Profissionais/genética , Adulto , Feminino , Perfilação da Expressão Gênica , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Sci Rep ; 7(1): 9890, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28852133

RESUMO

Quantitative modeling of microscopic genes regulatory mechanisms in an individual cell is a crucial step towards understanding various macroscopic physiological phenomena of cell populations. Based on the regulatory mechanisms of genes zeb1 and cdh1 in the growth and development of breast cancer cells, we propose a kinetic model at the level of single cell. By constructing the effective landscape of underlying stationary probability for the genes expressions, it is found that (i) each breast cancer cell has three phenotypic states (i.e., the stem-like, basal, and luminal states) which correspond to three attractions of the probability landscape. (ii) The interconversions between phenotypic states can be induced by the noise intensity and the property of phenotypic switching is quantified by the mean first-passage time. (iii) Under certain conditions, the probabilities of each cancer cell appearing in the three states are consistent with the macroscopic phenotypic equilibrium proportions in the breast cancer SUM159 cell line. (iv) Our kinetic model involving the TGF-ß signal can also qualitatively explain several macroscopic physiological phenomena of breast cancer cells, such as the "TGF-ß paradox" in tumor therapy, the five clinical subtypes of breast cancer cells, and the effects of transient TGF-ß on breast cancer metastasis.


Assuntos
Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Modelos Biológicos , Fenótipo , Algoritmos , Neoplasias da Mama/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Cinética
12.
J Ethnopharmacol ; 207: 57-66, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-28645780

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Danshen is a crude herbal drug isolated from dried roots of Salvia miltiorrhiza Bunge. This plant is widely used in oriental medicine for the treatment of cardiovascular and cerebrovascular diseases. The supercritical CO2 extract from Danshen (SCED) (57.85%, 5.67% and 4.55% for tanshinone IIA, tanshinone I and cryptotanshinone respectively) was studied in this article, whose potential molecular mechanism remains unclear, especially in anti-thrombosis. AIM OF THE STUDY: The present study was designed to observe the protective effect of SCED on ischemic stroke in rats and to explore the underlying anti-thrombosis mechanism. MATERIALS AND METHODS: Following induction of cerebral ischemia in rats by permanent middle cerebral artery occlusion (pMCAO). Neurological defect score, cerebral blood flow, infarct size, and brain edema were measured to evaluate the injury. Arteriovenous shunt thrombosis model and adenosine 5'-diphosphate (ADP) induced acute pulmonary embolism model were conducted to estimate the antithrombotic effect of SCED. In order to investigate the effects of SCED on platelet aggregation, rat platelet-rich-plasma (PRP) were incubated with SCED prior to the addition of the stimuli (ADP or 9, 11-dideoxy-11α, 9α-epoxymethanoprostaglandin F2α (U46619)). Aggregation was monitored in a light transmission aggregometer. Inhibitory effect of SCED on thromboxane A2 (TXA2) release was detected by ELISA kit. Phospholipase C (PLC)/ Protein kinase C (PKC) signaling pathway was analyzed by a Western blot technique. The effect of the SCED was also studied in vivo on bleeding time in mice. RESULTS: SCED improved the neurological defect score, increased cerebral blood flow, reduced infarct size and alleviated brain edema in rats exposed to pMCAO. After administration of SCED, thrombosis formation in arteriovenous shunt was inhibited and recovery time in pulmonary embolism was shortened. The inhibitory effect of SCED on platelet activation was further confirmed by TXB2 ELISA kit and Western blot analysis of PLC/PKC signaling pathway. CONCLUSIONS: SCED attenuates cerebral ischemic injury. The possible mechanism is that SCED inhibits thrombosis formation, platelet aggregation and activation of PLC/PKC pathway. On this basis, this new extract could be a promising agent to inhibit thrombosis formation and protect against cerebral ischemia injury.


Assuntos
Isquemia Encefálica/prevenção & controle , Medicamentos de Ervas Chinesas/farmacologia , Salvia miltiorrhiza/química , Acidente Vascular Cerebral/prevenção & controle , Animais , Western Blotting , Modelos Animais de Doenças , Feminino , Infarto da Artéria Cerebral Média , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ativação Plaquetária/efeitos dos fármacos , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Trombose/tratamento farmacológico , Fosfolipases Tipo C/metabolismo
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 23(2): 345-9, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25948183

RESUMO

OBJECTIVE: Based on our previous study showing the inhibition of lenkemia T cell proliferation by down-regulating PPP2R5C expression, this study was aimed to analyze the influence of down-regulating PPP2R5 expression via RNA interference on genes relatied with TAL1 signaling pathway by using gene chip technique. METHODS: The PPP2R5C-siRNA799 was transduced into Jurkat cells by nucleofection, the total RNA was isolated from treated Jurkat cells after culture for 48 hours; the target sequences were prepared by revevse transcription after mRNA purification, and were hybridized with affymetrix gene expression profile chip 3' IVT. The original image data were collected using affymetrix gene chip scanner 3 000, and the gene expression profile was analyzed using gene spring GX 11.0 soflware. RESULTS: The expression of all 26 genes related with TAL1 signaling pathway was changed, out of which the expression of 15 genes were up-regulated and the expression of 11 genes was down-regulated in PPP2R5C-siRNA 799-transfected Jurkat cells. The genes with significantly up-regulated expression were GATA1, TCF4, XRCC6 and TCF3, while the genes with significantly down-regulated expression were SIN3A and RUNX1. CONCLUSION: The down-regulation of PPP2R5C gene expression in Jurkat cells via RNA interference to a certain degree can inhibit TAL1 signaling pathway genes, thereby suppresses the proliferation of Jurkat cells.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proliferação de Células , Regulação para Baixo , Expressão Gênica , Humanos , Células Jurkat , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Fosfatase 2 , Interferência de RNA , RNA Mensageiro , RNA Interferente Pequeno , Transdução de Sinais , Transcriptoma , Transfecção
14.
Artigo em Inglês | MEDLINE | ID: mdl-26274216

RESUMO

Quantitative modeling of fluctuations of each phenotype is a crucial step towards a fundamental understanding of noise propagation through various phenotypic transition cascades. The theoretical formulas for noise propagation in various phenotypic transition cascades are derived by using the linear noise approximation of master equation and the logarithmic gain. By virtue of the theoretical formulas, we study the noise propagation in bidirectional and unidirectional phenotypic transition cascades, respectively. It is found that noise propagation in these two phenotypic transition cascades evidently differs: In the bidirectional cascade, a systemic random environment is provided by a correlated global component. The total noise of each phenotype is mainly determined by the intrinsic noise and the transmitted noise from other phenotypes. The intrinsic noise enlarged by interconversion through an added part shows a novel noise propagation mechanism. However, in the unidirectional cascade, the random environment of each downstream phenotype is provided by upstream phenotypes. The total noise of each downstream phenotype is mainly determined by the transmitted noises from upstream phenotypes. The intrinsic noise and the conversion noise can propagate in both bidirectional and unidirectional phenotypic transition cascades.


Assuntos
Modelos Genéticos , Fenótipo , Colo/microbiologia , Simulação por Computador
15.
Chin Med J (Engl) ; 117(3): 413-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15043783

RESUMO

BACKGROUND: We distinguished graft-versus-host disease (GVHD) from graft-versus-leukemia (GVL) effects and to investigate the distribution of T-cell receptor (TCR) V beta gene repertoire in individuals with leukemia before and after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from 10 normal individuals, 8 donors and 11 patients with leukemia before and after transplantation. Polymerase chain reaction (PCR) amplification of complementarity-determining region 3 (CDR3) of 24 TCR V beta genes was used to examine serial samples of PBMC. The PCR products were further analyzed by genescan to evaluate clonality of T cells. RESULTS: The 24 TCR V beta gene repertoire displayed highly diverse and polyclonal spectratypes in all normal individuals and 4 of 8 donors. Another 4 donors expressed part of the 24 TCR V beta subfamily and 1 donor had oligoclonality. The expressions of the 24 TCR V beta subfamilies were skewed and restricted in 11 leukemia patients before and after transplantation. Some absences of 24 TCR V beta subfamily expression were quite similar between the recipients pro-transplantation and related donors. The number of subfamilies expressed increased over time post-transplantation, but the restricted expressions of the subfamily could last 6 - 30 months after transplantation. All patients with GVHD and some without GVHD exhibited T cell clonal expansion. The expansive T cell clone was distributed in V beta 2-3, 16-17, 18-19, 21 and V beta 23 in patients with GVHD and in V beta 7, 9, 16 and 19 in patients without GVHD. One patient with syngeneic-HSCT (syn-HSCT) had V beta 15 and 16 T cell expansion after transplantation. One patient displayed V beta 18 T cell expansion after donor lymphocyte infusion (DLI). CONCLUSIONS: Normal individuals express the entire 24 TCR V beta gene repertoire and have polyclonal distribution. However, the TCR V beta gene repertoire is only partially expressed in some donors. The TCR V beta gene repertoire is restrictedly expressed in a skew fashion in patients with leukemia before and after transplantation. The number of TCR V beta gene subfamilies increases over time post-transplantation. GVHD and GVL effects may induce the proliferation of T cell clones. Clinical GVL response may be distinguished from GVHD alloreactivity through the host MHC antigen.


Assuntos
Doença Enxerto-Hospedeiro/genética , Efeito Enxerto vs Leucemia/genética , Transplante de Células-Tronco Hematopoéticas , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Humanos , Leucemia/genética , Leucemia/terapia , Reação em Cadeia da Polimerase
16.
Chin Med J (Engl) ; 117(6): 840-3, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15198883

RESUMO

BACKGROUND: In general, it is very important to understand the state of T cell immune response against tumor cells in leukemia patients and it is especially critical to assess the T cell repertoire of untreated patients. As we know, few studies have dealt with the distribution of oligoclonal T cells in leukemia, so we investigated the distribution and clonality of TCR Vbeta repertoire of T cells in patients with chronic myelogenous leukemia (CML) in chronic phase. METHODS: The complementarity determining region 3 (CDR3) of TCR Vbeta24 subfamily genes were amplified in peripheral blood mononuclear cells from 27 cases with CML using reverse transcription-polymerase chain reaction (RT-PCR). In order to observe the distribution of TCR Vbeta repertoire, the PCR products were further analyzed by genescan technique to evaluate clonality of the detectable TCR Vbeta T cells. The PCR products of the oligoclonal T cells from three cases were analyzed by direct sequencing to define the sequence of CDR3. RESULTS: The expression pattern of TCR Vbeta repertoire in different individuals are different. Vbeta2-21 subfamilies could be detected in CML cases. The frequent usage Vbeta repertoire in CML was Vbeta1, Vbeta2 or Vbeta13. Most of the PCR products from 27 patients displayed polyclonality, while a part of the PCR products from 21 out of 27 samples displayed clonal expansion pattern. The clonal expanded T cells in CML could be found in Vbeta16 subfamilies. The frequent usage of Vbeta genes in clonal expansion was Vbeta3, Vbeta13 or Vbeta21. Multiple Vbeta clonal expansion was a general phenomenon in the same patient. The CDR3 sequence of Vbeta21 oligoclonal T cells from 3 cases showed some difference in splice regions and in the usage of J segments. CONCLUSIONS: These results indicated that clonal expanded T cells could be found in patients with CML and were tendentious in Vbeta3, Vbeta13 and Vbeta21 subfamilies that may be related to the specific immune response for leukemia cell associated antigen.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Linfócitos T/imunologia , Células Clonais , Regiões Determinantes de Complementaridade/análise , Humanos , Linfócitos T/patologia
17.
Artigo em Zh | MEDLINE | ID: mdl-15256150

RESUMO

OBJECTIVE: To analyze the content of signal joint T-cell receptor excision DNA circles signal joint T-cell receptor excision DNA circles (sjTRECs) within peripheral blood mononuclear cells (PBMCs), thereby to infer the level of naive T cells and the recent thymic output function in benzene-exposed workers. METHODS: Quantitative detection of sjTRECs in DNA of peripheral blood mononuclear cells from 11 normal individuals and 62 benzene-exposed workers were performed by real-time polymerase chain reaction (PCR) and TaqMan technique. RESULTS: The median value of sjTRECs copies/1,000 PBMCs was 7.81 in normal individuals whereas it was 2.56 copies/1 000 PBMCs in age-unadjusted benzene-exposed workers (P < 0.01). And its levels were obviously different between two different age groups: that in 30-year-old group (1.76 copies/1,000 PBMCs, n = 23) was less than

Assuntos
Benzeno/intoxicação , Rearranjo Gênico do Linfócito T/genética , Exposição Ocupacional , Timo/fisiologia , Adulto , Feminino , Rearranjo Gênico do Linfócito T/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Timo/imunologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-24730882

RESUMO

The number of stem cells in a colonic crypt is often very small, which leads to large intrinsic fluctuations in the cell population. Based on the model of cell population dynamics with linear feedback in a colonic crypt, we present a stochastic dynamics of the cell population [including stem cells (SCs), transit amplifying cells (TACs), and fully differentiated cells (FDCs)]. The Fano factor, covariance, and susceptibility formulas of the cell population around the steady state are derived by using the Langevin theory. In the range of physiologically reasonable parameter values, it is found that the stationary populations of TACs and FDCs exhibit an approximately threshold behavior as a function of the net growth rate of TACs, and the reproductions of TACs and FDCs can be classified into three regimens: controlled, crossover, and uncontrolled. With the increasing of the net growth rate of TACs, there is a maximum of the relative intrinsic fluctuations (i.e., the Fano factors) of TACs and FDCs in the crossover region. For a fixed differentiation rate and the net growth rate of SCs, the covariance of fluctuations between SCs and TACs has a maximum in the crossover region. However, the susceptibilities of both TACs and FDCs to the net growth rate of TACs have a minimum in the crossover region.


Assuntos
Colo/citologia , Colo/fisiologia , Enterócitos/citologia , Enterócitos/fisiologia , Modelos Biológicos , Células-Tronco/citologia , Células-Tronco/fisiologia , Diferenciação Celular/fisiologia , Células Cultivadas , Simulação por Computador , Humanos , Modelos Estatísticos
20.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 27(2): 150-3, 2011 Feb.
Artigo em Zh | MEDLINE | ID: mdl-21315043

RESUMO

AIM: To analyze the expression level of TCRζ chain gene in the DLBCL-associated antigen-specific T cells before and after being activated by coculture with Toledo cells (DLBCL cell line). METHODS: Real-time PCR with SYBR GreenI technique was used for detecting TCRζ chain expression in activated and unactivated DLBCL-associated antigen-specific T cells. ß2 microglobulin gene (ß2M) was used as an endogenous reference. Relative mRNA expression level of TCRζ gene was analyzed by the formula of both 2(-δCt); ×100% and 2(-δδCt);. RESULTS: Compared with (1.74±0.28)% of the relative mRNA expression level of TCRζ gene in TCR gene-untransduced T cells, the expression level of TCRζ gene was (1.78±0.22)% in unactivated TCR gene-transduced T cells and showed no obvious increase. While the expression of TCRζ gene arrived at (11.54±1.98)% in the activated TCR gene-modified T cells, which was significantly higher than that in unactivated TCR gene-modified and TCR gene-untransduced T cells (P<0.05), and was increased (6.59±0.80) and (6.48±0.36) times, respectively. CONCLUSION: The expression of TCRζ chain was up-regulated, when TCR gene-modified T cells were activated by the stimulation of specific antigens.


Assuntos
Antígenos de Neoplasias/imunologia , Regulação da Expressão Gênica , Genes Codificadores da Cadeia delta de Receptores de Linfócitos T , Linfoma Difuso de Grandes Células B/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Regulação da Expressão Gênica/imunologia , Vetores Genéticos/genética , Humanos , Células Jurkat , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Linfoma Difuso de Grandes Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Temperatura de Transição
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA