Cellular senescence is a signal transduction process which maintained genomic stability and stopped mammalian cell growth. Furthermore, cellular senescence induces a protective response to a variety of DNA damage. How...Cellular senescence is a signal transduction process which maintained genomic stability and stopped mammalian cell growth. Furthermore, cellular senescence induces a protective response to a variety of DNA damage. However, this process is also associated with apoptosis, upregulated secretion of inflammatory cytokine, and promoted surrounding tissue damage. When cellular senescence accumulates to a certain extent, it triggers geriatric diseases, such as chronic inflammation, immune senescence-associated tumors and incontrollable infections. Cellular senescence gene SENEX, which was cloned in 2004, has been demonstrated to play a unique gatekeeper function in human endothelial cells when stress-induced pre-mature senescence and apoptosis occurr. The phenomenon that CD4+CD25+ Treg cells accumulated in the aged population has been well studied in recent years. Now Treg accumulation related to immune-pathology has attracted more interest. CD4+CD25+ Treg did not decline and age, but accumulated and suppressed immunoreaction. The enhanced Treg number and function may be associated with stress-induced premature senescence-mediated unique cellular senescence protection mechanisms, and SENEX may play a critical role in this process. In this article, we summarize the cellular senescence and SENEX gene in the accumulation and functional activity of CD4+CD25+ Treg in the elderly.展开更多
Background: It is widely known that the human immune-deficiency virus (HIV) induces biochemical and physiological changes in affected persons. Consequently, the overall aim of this study was to evaluate the HIV-1 RNA ...Background: It is widely known that the human immune-deficiency virus (HIV) induces biochemical and physiological changes in affected persons. Consequently, the overall aim of this study was to evaluate the HIV-1 RNA viral load, CD4 count, and certain haematological parameters among HIV treatment-na?ve subjects in the Enugu metropolis of Nigeria. Materials and Methods: A total of 252 HIV-infected, ART-native subjects (≥18) attending the University of Nigeria Teaching Hospital (UNTH) in Ituku-Ozalla, Enugu were recruited for this study and were made up of 157 (62.3%) females and 95 (37.7%) males. A total of 250 HIV-negative subjects were used as control subjects (100 males and 150 females). Blood samples were collected from all the participants and their HIV-1 status was confirmed by an immunoblot confirmatory test. Their haematological parameters and CD4 count were evaluated, while the HIV-1 viral load was only assessed on confirmed HIV-positive subjects. Results: There was female predominance (62.3%) among these HIV-positive subjects. The mean age of HIV-positive subjects was 39.16 ± 10.08 years while the mean age of the control subjects was 34.8 ± 8.6 years. The age group of 31 - 40 years (102/252 (40.5%)) constituted most of the test subjects. The total white blood cells (TWBC) (6.05 ± 5.46), lymphocyte counts (36 ± 14), haemoglobin concentrations (Hb) (9.85 ± 7.36) and the CD4 counts (242 ± 228) of the HIV-infected subjects showed a significant difference when compared with their control counterpart values of TWBC (4.5 ± 0.568), lymphocytes (39.67 ± 8.2), Hb (13.48 ± 1.5), and CD4 counts (807 ± 249) (p 0.05). Anaemia, lymphocytopenia, and thrombocytopenia were the haematological abnormalities seen in the HIV-positive subjects. HIV viral load correlated with haemoglobin concentration, CD4 count, lymphocyte count, and neutrophil count (p Conclusion: Prognostic factors, such as haemoglobin concentrations, CD4 counts, lymphocyte counts, and neutrophil counts can be used to monitor patients’ viral loads since they correlate with the latter;furthermore, age is a factor that should be considered in the management of HIV-positive patients.展开更多
Survival of HIV/AIDS patients is crucially dependent on comprehensive and targeted medical interventions such as supply of antiretroviral therapy and monitoring disease progression with CD4 T-cell counts. Statistical ...Survival of HIV/AIDS patients is crucially dependent on comprehensive and targeted medical interventions such as supply of antiretroviral therapy and monitoring disease progression with CD4 T-cell counts. Statistical modelling approaches are helpful towards this goal. This study aims at developing Bayesian joint models with assumed generalized error distribution (GED) for the longitudinal CD4 data and two accelerated failure time distributions, Lognormal and loglogistic, for the survival time of HIV/AIDS patients. Data are obtained from patients under antiretroviral therapy follow-up at Shashemene referral hospital during January 2006-January 2012 and at Bale Robe general hospital during January 2008-March 2015. The Bayesian joint models are defined through latent variables and association parameters and with specified non-informative prior distributions for the model parameters. Simulations are conducted using Gibbs sampler algorithm implemented in the WinBUGS software. The results of the analyses of the two different data sets show that distributions of measurement errors of the longitudinal CD4 variable follow the generalized error distribution with fatter tails than the normal distribution. The Bayesian joint GED loglogistic models fit better to the data sets compared to the lognormal cases. Findings reveal that patients’ health can be improved over time. Compared to the males, female patients gain more CD4 counts. Survival time of a patient is negatively affected by TB infection. Moreover, increase in number of opportunistic infection implies decline of CD4 counts. Patients’ age negatively affects the disease marker with no effects on survival time. Improving weight may improve survival time of patients. Bayesian joint models with GED and AFT distributions are found to be useful in modelling the longitudinal and survival processes. Thus we recommend the generalized error distributions for measurement errors of the longitudinal data under the Bayesian joint modelling. Further studies may investigate the models with various types of shared random effects and more covariates with predictions.展开更多
文摘Cellular senescence is a signal transduction process which maintained genomic stability and stopped mammalian cell growth. Furthermore, cellular senescence induces a protective response to a variety of DNA damage. However, this process is also associated with apoptosis, upregulated secretion of inflammatory cytokine, and promoted surrounding tissue damage. When cellular senescence accumulates to a certain extent, it triggers geriatric diseases, such as chronic inflammation, immune senescence-associated tumors and incontrollable infections. Cellular senescence gene SENEX, which was cloned in 2004, has been demonstrated to play a unique gatekeeper function in human endothelial cells when stress-induced pre-mature senescence and apoptosis occurr. The phenomenon that CD4+CD25+ Treg cells accumulated in the aged population has been well studied in recent years. Now Treg accumulation related to immune-pathology has attracted more interest. CD4+CD25+ Treg did not decline and age, but accumulated and suppressed immunoreaction. The enhanced Treg number and function may be associated with stress-induced premature senescence-mediated unique cellular senescence protection mechanisms, and SENEX may play a critical role in this process. In this article, we summarize the cellular senescence and SENEX gene in the accumulation and functional activity of CD4+CD25+ Treg in the elderly.
文摘Background: It is widely known that the human immune-deficiency virus (HIV) induces biochemical and physiological changes in affected persons. Consequently, the overall aim of this study was to evaluate the HIV-1 RNA viral load, CD4 count, and certain haematological parameters among HIV treatment-na?ve subjects in the Enugu metropolis of Nigeria. Materials and Methods: A total of 252 HIV-infected, ART-native subjects (≥18) attending the University of Nigeria Teaching Hospital (UNTH) in Ituku-Ozalla, Enugu were recruited for this study and were made up of 157 (62.3%) females and 95 (37.7%) males. A total of 250 HIV-negative subjects were used as control subjects (100 males and 150 females). Blood samples were collected from all the participants and their HIV-1 status was confirmed by an immunoblot confirmatory test. Their haematological parameters and CD4 count were evaluated, while the HIV-1 viral load was only assessed on confirmed HIV-positive subjects. Results: There was female predominance (62.3%) among these HIV-positive subjects. The mean age of HIV-positive subjects was 39.16 ± 10.08 years while the mean age of the control subjects was 34.8 ± 8.6 years. The age group of 31 - 40 years (102/252 (40.5%)) constituted most of the test subjects. The total white blood cells (TWBC) (6.05 ± 5.46), lymphocyte counts (36 ± 14), haemoglobin concentrations (Hb) (9.85 ± 7.36) and the CD4 counts (242 ± 228) of the HIV-infected subjects showed a significant difference when compared with their control counterpart values of TWBC (4.5 ± 0.568), lymphocytes (39.67 ± 8.2), Hb (13.48 ± 1.5), and CD4 counts (807 ± 249) (p 0.05). Anaemia, lymphocytopenia, and thrombocytopenia were the haematological abnormalities seen in the HIV-positive subjects. HIV viral load correlated with haemoglobin concentration, CD4 count, lymphocyte count, and neutrophil count (p Conclusion: Prognostic factors, such as haemoglobin concentrations, CD4 counts, lymphocyte counts, and neutrophil counts can be used to monitor patients’ viral loads since they correlate with the latter;furthermore, age is a factor that should be considered in the management of HIV-positive patients.
文摘Survival of HIV/AIDS patients is crucially dependent on comprehensive and targeted medical interventions such as supply of antiretroviral therapy and monitoring disease progression with CD4 T-cell counts. Statistical modelling approaches are helpful towards this goal. This study aims at developing Bayesian joint models with assumed generalized error distribution (GED) for the longitudinal CD4 data and two accelerated failure time distributions, Lognormal and loglogistic, for the survival time of HIV/AIDS patients. Data are obtained from patients under antiretroviral therapy follow-up at Shashemene referral hospital during January 2006-January 2012 and at Bale Robe general hospital during January 2008-March 2015. The Bayesian joint models are defined through latent variables and association parameters and with specified non-informative prior distributions for the model parameters. Simulations are conducted using Gibbs sampler algorithm implemented in the WinBUGS software. The results of the analyses of the two different data sets show that distributions of measurement errors of the longitudinal CD4 variable follow the generalized error distribution with fatter tails than the normal distribution. The Bayesian joint GED loglogistic models fit better to the data sets compared to the lognormal cases. Findings reveal that patients’ health can be improved over time. Compared to the males, female patients gain more CD4 counts. Survival time of a patient is negatively affected by TB infection. Moreover, increase in number of opportunistic infection implies decline of CD4 counts. Patients’ age negatively affects the disease marker with no effects on survival time. Improving weight may improve survival time of patients. Bayesian joint models with GED and AFT distributions are found to be useful in modelling the longitudinal and survival processes. Thus we recommend the generalized error distributions for measurement errors of the longitudinal data under the Bayesian joint modelling. Further studies may investigate the models with various types of shared random effects and more covariates with predictions.
