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1.
Am J Respir Crit Care Med ; 200(3): 370-380, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30694692

RESUMEN

Rationale: There is poor understanding about protective immunity and the pathogenesis of cavitation in patients with tuberculosis.Objectives: To map pathophysiological pathways at anatomically distinct positions within the human tuberculosis cavity.Methods: Biopsies were obtained from eight predetermined locations within lung cavities of patients with multidrug-resistant tuberculosis undergoing therapeutic surgical resection (n = 14) and healthy lung tissue from control subjects without tuberculosis (n = 10). RNA sequencing, immunohistochemistry, and bacterial load determination were performed at each cavity position. Differentially expressed genes were normalized to control subjects without tuberculosis, and ontologically mapped to identify a spatially compartmentalized pathophysiological map of the cavity. In silico perturbation using a novel distance-dependent dynamical sink model was used to investigate interactions between immune networks and bacterial burden, and to integrate these identified pathways.Measurements and Main Results: The median (range) lung cavity volume on positron emission tomography/computed tomography scans was 50 cm3 (15-389 cm3). RNA sequence reads (31% splice variants) mapped to 19,049 annotated human genes. Multiple proinflammatory pathways were upregulated in the cavity wall, whereas a downregulation "sink" in the central caseum-fluid interface characterized 53% of pathways including neuroendocrine signaling, calcium signaling, triggering receptor expressed on myeloid cells-1, reactive oxygen and nitrogen species production, retinoic acid-mediated apoptosis, and RIG-I-like receptor signaling. The mathematical model demonstrated that neuroendocrine, protein kinase C-θ, and triggering receptor expressed on myeloid cells-1 pathways, and macrophage and neutrophil numbers, had the highest correlation with bacterial burden (r > 0.6), whereas T-helper effector systems did not.Conclusions: These data provide novel insights into host immunity to Mycobacterium tuberculosis-related cavitation. The pathways defined may serve as useful targets for the design of host-directed therapies, and transmission prevention interventions.


Asunto(s)
Mycobacterium tuberculosis/aislamiento & purificación , Análisis de Secuencia de ARN , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Pulmonar/microbiología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/aislamiento & purificación , Adulto Joven
2.
Am J Respir Crit Care Med ; 198(1): 104-116, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29425052

RESUMEN

RATIONALE: The advent of extensively drug-resistant (XDR) tuberculosis (TB) and totally drug-resistant TB, with limited or no treatment options, has facilitated renewed interest in host-directed immunotherapy, particularly for therapeutically destitute patients. However, the selection and utility of such approaches depend on understanding the host immune response in XDR-TB, which hitherto remains unexplored. OBJECTIVES: To determine the host immunological profile in patients with XDR-TB, compared with drug-sensitive TB (DS-TB), using peripheral blood and explanted lung tissue. METHODS: Blood and explanted lung tissue were obtained from patients with XDR-TB (n = 31), DS-TB (n = 20), and presumed latent TB infection (n = 20). T-cell phenotype (T-helper cell type 1 [Th1]/Th2/Th17/regulatory T cells [Tregs]) was evaluated in all patient groups, and Treg function assessed in XDR-TB nonresponders by coculturing PPD-preprimed effector T cells with H37Rv-infected monocyte-derived macrophages, with or without autologous Tregs. Mycobacterial containment was evaluated by counting colony-forming units. MEASUREMENTS AND MAIN RESULTS: Patients failing XDR-TB treatment had an altered immunophenotype characterized by a substantial increase in the frequency (median; interquartile range) of CD4+CD25+FoxP3+ Tregs (11.5%; 5.9-15.2%) compared with DS-TB (3.4%; 1.6-5.73%; P < 0.001) and presumed latent TB infection (1.8%; 1.2-2.3%; P < 0.001), which was unrelated to disease duration. Tregs isolated from patients with XDR-TB suppressed T-cell proliferation (up to 90%) and subverted containment of H37Rv-infected monocyte-derived macrophages (by 30%; P = 0.03) by impairing effector T-cell function through a mechanism independent of direct cell-to-cell contact, IL-10, TGF (transforming growth factor)-ß, and CTLA-4 (cytotoxic T-lymphocyte-associated protein 4). CONCLUSIONS: Collectively, these data suggest that Tregs may be contributing to immune dysfunction, and bacterial persistence, in patients with XDR-TB. The relevant cellular pathways may serve as potential targets for immunotherapeutic intervention.


Asunto(s)
Antituberculosos/inmunología , Antituberculosos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple/inmunología , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Tuberculosis Extensivamente Resistente a Drogas/inmunología , Mycobacterium tuberculosis/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
3.
Am J Respir Crit Care Med ; 198(9): 1208-1219, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-29877726

RESUMEN

RATIONALE: Acquired resistance is an important driver of multidrug-resistant tuberculosis (TB), even with good treatment adherence. However, exactly what initiates the resistance and how it arises remain poorly understood. OBJECTIVES: To identify the relationship between drug concentrations and drug susceptibility readouts (minimum inhibitory concentrations [MICs]) in the TB cavity. METHODS: We recruited patients with medically incurable TB who were undergoing therapeutic lung resection while on treatment with a cocktail of second-line anti-TB drugs. On the day of surgery, antibiotic concentrations were measured in the blood and at seven prespecified biopsy sites within each cavity. Mycobacterium tuberculosis was grown from each biopsy site, MICs of each drug identified, and whole-genome sequencing performed. Spearman correlation coefficients between drug concentration and MIC were calculated. MEASUREMENTS AND MAIN RESULTS: Fourteen patients treated for a median of 13 months (range, 5-31 mo) were recruited. MICs and drug resistance-associated single-nucleotide variants differed between the different geospatial locations within each cavity, and with pretreatment and serial sputum isolates, consistent with ongoing acquisition of resistance. However, pretreatment sputum MIC had an accuracy of only 49.48% in predicting cavitary MICs. There were large concentration-distance gradients for each antibiotic. The location-specific concentrations inversely correlated with MICs (P < 0.05) and therefore acquired resistance. Moreover, pharmacokinetic/pharmacodynamic exposures known to amplify drug-resistant subpopulations were encountered in all positions. CONCLUSIONS: These data inform interventional strategies relevant to drug delivery, dosing, and diagnostics to prevent the development of acquired resistance. The role of high intracavitary penetration as a biomarker of antibiotic efficacy, when assessing new regimens, requires clarification.


Asunto(s)
Antituberculosos/farmacología , Pulmón/efectos de los fármacos , Pulmón/patología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/patología , Adolescente , Adulto , Antituberculosos/uso terapéutico , Biopsia , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
4.
Alcohol Clin Exp Res ; 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29870072

RESUMEN

BACKGROUND: A growing body of evidence in animal models has implicated alcohol-induced alterations in epigenetic programming as an important mechanism in fetal alcohol spectrum disorders (FASD). Imprinted genes, a subset of epigenetically regulated genes that are sensitive to the prenatal environment, are chiefly involved in growth and neurobehavior. We tested the hypothesis that alterations in placental imprinted gene expression mediate fetal alcohol growth restriction. METHODS: Placental expression of 109 genes previously shown to be imprinted and expressed in the placenta was assessed using the NanoString™ nCounter Analysis System in flash-frozen samples from 34 heavy drinkers and 31 control women in Cape Town, South Africa, from whom prospective pregnancy alcohol consumption data had been obtained. Length/height, weight, and head circumference were measured at 6.5 and 12 months and at an FASD diagnostic clinic (at ages 1.1 to 4.6 years) that we organized. Imprinted gene expression between exposed and control placentas was compared using the limma R package. The relation of alcohol exposure to World Health Organization length-for-age z-scores was examined before and after inclusion of expression for each alcohol-related imprinted gene, using hierarchical mixed regression models with repeated measures. RESULTS: Heavy drinkers averaged 8 standard drinks on 2 to 3 days/wk (vs. 0 for controls). Prenatal alcohol exposure was associated with smaller length/height and weight during the postnatal period. Heavy exposure was related to alterations in expression of 11 of 93 expressed imprinted genes, including increased expression of 5 genes found to be negatively associated with growth and decreased expression of 3 genes positively associated with growth. Alcohol-related alterations in expression of 5 genes statistically mediated the effect of prenatal alcohol exposure on length. CONCLUSIONS: These findings identify alcohol-related alterations in placental imprinted gene expression as potential biomarkers of adverse effect in FASD and suggest that these alterations may play a mechanistic role in fetal alcohol growth restriction. Future studies are needed to determine whether alterations in imprinted gene expression also mediate FASD neurobehavioral deficits and whether such alterations are amenable to intervention.

5.
J Infect Dis ; 214(9): 1309-1318, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27462092

RESUMEN

BACKGROUND: Human immunodeficiency virus type 1 (HIV)-infected persons are more susceptible to tuberculosis than HIV-uninfected persons. Low peripheral CD4+ T-cell count is not the sole cause of higher susceptibility, because HIV-infected persons with a high peripheral CD4+ T-cell count and those prescribed successful antiretroviral therapy (ART) remain more prone to active tuberculosis than HIV-uninfected persons. We hypothesized that the increase in susceptibility is caused by the ability of HIV to manipulate Mycobacterium tuberculosis-associated granulomas. METHODS: We examined 71 excised cervical lymph nodes (LNs) from persons with HIV and M. tuberculosis coinfection, those with HIV monoinfection, and those with M. tuberculosis monoinfection with a spectrum of peripheral CD4+ T-cell counts and ART statuses. We quantified differences in M. tuberculosis levels, HIV p24 levels, cellular response, and cytokine presence within granulomas. RESULTS: HIV increased M. tuberculosis numbers and reduced CD4+ T-cell counts within granulomas. Peripheral CD4+ T-cell depletion correlated with granulomas that contained fewer CD4+ and CD8+ T cells, less interferon γ, more neutrophils, more interleukin 10 (IL-10), and increased M. tuberculosis numbers. M. tuberculosis numbers correlated positively with IL-10 and interferon α levels and fewer CD4+ and CD8+ T cells. ART reduced IL-10 production. CONCLUSIONS: Peripheral CD4+ T-cell depletion correlated with increased M. tuberculosis presence, increased IL-10 production, and other phenotypic changes within granulomas, demonstrating the HIV infection progressively changes these granulomas.


Asunto(s)
Coinfección/metabolismo , Granuloma/metabolismo , Infecciones por VIH/metabolismo , Interleucina-10/metabolismo , Ganglios Linfáticos/metabolismo , Tuberculosis/metabolismo , Adulto , Anciano , Recuento de Linfocito CD4/métodos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/microbiología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/microbiología , Linfocitos T CD8-positivos/virología , Coinfección/microbiología , Coinfección/virología , Femenino , Granuloma/microbiología , Granuloma/virología , Infecciones por VIH/microbiología , Infecciones por VIH/virología , VIH-1/patogenicidad , Humanos , Interferón gamma/metabolismo , Ganglios Linfáticos/microbiología , Ganglios Linfáticos/virología , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/patogenicidad , Tuberculosis/microbiología , Tuberculosis/virología , Adulto Joven
6.
Hepatology ; 61(5): 1721-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25644940

RESUMEN

UNLABELLED: Liver disease complicates human immunodeficiency virus (HIV)/acquired immune deficiency syndrome; however, liver pathology data are limited, particularly from high HIV prevalence countries. We investigated the spectrum and clinicopathological correlates of liver pathology in a high HIV burden setting. In a single-center study, all HIV/acquired immune deficiency syndrome patients with complete clinical and demographic data who underwent liver biopsy were analyzed and clinicopathologically assessed by hepatologists and one of two experienced liver pathologists. We evaluated 301 patients, with a median age of 34 (interquartile range 29-40) years. Women (n = 143) were younger than men (n = 158), with a median age of 33 (interquartile range 28-37) versus 35 (interquartile range 31-41) years, P = 0.001. The majority, 76.1%, were black African. Median CD4 at time of biopsy was 127 (52-260) cells/mm(3) . Drug-induced liver injury was the predominant finding (42.2%), followed by granulomatous inflammation (29%), steatosis/steatohepatitis (19.3%), hepatitis B (19%), and hepatitis C coinfection (3.3%), with more than one pathology in 16.2%. With granulomatous inflammation, 52% met the criteria for tuberculosis immune reconstitution syndrome. By univariate analysis, cotrimoxazole and antiretroviral therapy conferred risk for drug injury (odds ratio [OR] = 2.78 [1.72-4.48], P < 0.001; OR = 1.69 [1.06-2.68], P = 0.027). In multivariate analysis, cotrimoxazole was associated with a cholestatic or ductopenic injury (OR = 7.05 [2.50-19.89], P < 0.001; OR = 17.6 [3.26-95.3], P < 0.0001); efavirenz was associated with nonspecific hepatitis or submassive necrosis (OR = 4.3 [1.92-9.83], P < 0.001; OR = 10.46 [2.7-40.5], P < 0.001). Cholestatic injury was associated with female gender and a CD4 of >200 cells/mm(3) , and submassive necrosis was associated with younger age. Hepatitis B demonstrated no association. CONCLUSION: In a high HIV burden area, drug-induced liver injury due to antiretroviral therapy and cotrimoxazole was a frequent clinicopathological finding; Mycobacterium tuberculosis was the leading opportunistic infection, with more than half of patients fulfilling criteria for tuberculosis immune reconstitution syndrome; liver biopsy remains a useful diagnostic procedure in this setting.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Hepatopatías/etiología , Hepatopatías/patología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino
7.
Alcohol Clin Exp Res ; 40(4): 753-64, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27038593

RESUMEN

BACKGROUND: Animal studies have demonstrated adverse effects of prenatal alcohol exposure on placental development, but few studies have examined these effects in humans. Little is known about effects of prenatal exposure to methamphetamine, marijuana, and cigarette smoking on placental development. METHODS: Placentas were collected from 103 Cape Coloured (mixed ancestry) pregnant women recruited at their first antenatal clinic visit in Cape Town, South Africa. Sixty-six heavy drinkers and 37 nondrinkers were interviewed about their alcohol, cigarette smoking, and drug use at 3 antenatal visits. A senior pathologist, blinded to exposure status, performed comprehensive pathology examinations on each placenta using a standardized protocol. In multivariable regression models, effects of prenatal exposure were examined on placental size, structure, and presence of infections and meconium. RESULTS: Drinkers reported a binge pattern of heavy drinking, averaging 8.0 drinks/occasion across pregnancy on 1.4 d/wk. 79.6% smoked cigarettes; 22.3% used marijuana; and 17.5% used methamphetamine. Alcohol exposure was related to decreased placental weight and a smaller placenta-to-birthweight ratio. By contrast, methamphetamine was associated with larger placental weight and a larger placenta-to-birthweight ratio. Marijuana was also associated with larger placental weight. Alcohol exposure was associated with increased risk of placental hemorrhage. Prenatal alcohol, drug, and cigarette use were not associated with chorioamnionitis, villitis, deciduitis, or maternal vascular underperfusion. Alcohol and cigarette smoking were associated with a decreased risk of intrauterine passing of meconium, a sign of acute fetal stress and/or hypoxia; methamphetamine, with an increased risk. CONCLUSIONS: This is the first human study to show that alcohol, methamphetamine, and marijuana were associated with distinct patterns of pathology, suggesting different mechanisms mediating their effects on placental development. Given the growing body of evidence linking placental abnormalities to neurodevelopmental deficits, these findings may be important in the long-term teratogenic effects of prenatal alcohol and drug exposure.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Fumar Marihuana/efectos adversos , Metanfetamina/efectos adversos , Placenta/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/patología , Etanol/efectos adversos , Femenino , Humanos , Estudios Longitudinales , Fumar Marihuana/patología , Metanfetamina/administración & dosificación , Placenta/patología , Embarazo , Efectos Tardíos de la Exposición Prenatal/patología , Estudios Prospectivos , Fumar/efectos adversos , Fumar/patología , Adulto Joven
8.
BMC Pulm Med ; 15: 38, 2015 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-25896166

RESUMEN

BACKGROUND: There is a paucity of clinical and histopathological data about HIV-associated lymphocytic interstitial pneumonitis (LIP) in adults from HIV endemic settings. The role of Ebstein-Barr virus (EBV) in the pathogenesis remains unclear. METHODS: We reviewed the clinical, radiographic and histopathological features of suspected adult LIP cases at the Groote Schuur Hospital, Cape Town South Africa, over a 6 year period. Archived tissue sections were stained for CD3, CD4, CD8, CD20 and LMP-1 antigen (an EBV marker). RESULTS: 42 cases of suspected LIP(100% HIV-infected) were identified. 75% of patients were empirically treated for TB prior to being referred to the chest service for further investigation. Tissue samples were obtained using trans-bronchial biopsy. 13/42 were classified as definite LIP (lymphocytic infiltrate with no alternative diagnosis), 19/42 probable LIP (lymphocytic infiltrate but evidence of anthracosis or fibrosis) and 10 as non-LIP (alternative histological diagnosis). Those with definite LIP were predominantly young females (85%) with a median CD4 count of 194 (IQR 119-359). Clinical or radiological features had poor predictive value for LIP. Histologically, the lymphocytic infiltrate comprised mainly B cells and CD8 T cells. The frequency of positive EBV LMP-1 antigen staining was similar in definite and non- LIP patients [(2/13 (15%) vs. 3/10 (30%); p = 0.52]. CONCLUSIONS: In a HIV endemic setting adult HIV-associated LIP occurs predominantly in young women. The diagnosis can often be made on transbronchial biopsy and is characterized by a predominant CD8 T cell infiltrate. No association with EBV antigen was found.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Enfermedades Endémicas , Infecciones por VIH/epidemiología , Enfermedades Pulmonares Intersticiales/inmunología , Adulto , Antígenos CD20/inmunología , Complejo CD3/inmunología , Antígenos CD4/inmunología , Antígenos CD8/inmunología , Femenino , Infecciones por VIH/complicaciones , Recursos en Salud , Humanos , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades Pulmonares Intersticiales/fisiopatología , Masculino , Persona de Mediana Edad , Sudáfrica/epidemiología , Proteínas de la Matriz Viral/metabolismo , Adulto Joven
9.
J Genet Couns ; 23(2): 147-55, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24122200

RESUMEN

Biallelic germline mutations in mismatch repair genes predispose to constitutional mismatch repair deficiency syndrome (CMMR-D). The condition is characterized by a broad spectrum of early-onset tumors, including hematological, brain and bowel and is frequently associated with features of Neurofibromatosis type 1. Few definitive screening recommendations have been suggested and no published reports have described predictive testing. We report on the first case of predictive testing for CMMR-D following the identification of two non-consanguineous parents, with the same heterozygous mutation in MLH1: c.1528C > T. The genetic counseling offered to the family, for their two at-risk daughters, is discussed with a focus on the ethical considerations of testing children for known cancer-causing variants. The challenges that are encountered when reporting on heterozygosity in a child younger than 18 years (disclosure of carrier status and risk for Lynch syndrome), when discovered during testing for homozygosity, are addressed. In addition, the identification of CMMR-D in a three year old, and the recommended clinical surveillance that was proposed for this individual is discussed. Despite predictive testing and presymptomatic screening, the sudden death of the child with CMMR-D syndrome occurred 6 months after her last surveillance MRI. This report further highlights the difficulty of developing guidelines, as a result of the rarity of cases and diversity of presentation.


Asunto(s)
Disparidad de Par Base , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Neoplasias/genética , Adulto , Secuencia de Bases , Niño , Cartilla de ADN , Humanos , Reacción en Cadena de la Polimerasa , Adulto Joven
10.
Gene ; 894: 147951, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37918548

RESUMEN

BACKGROUND: Fetal alcohol spectrum disorders (FASD) are the most common preventable cause of birth defects and neurodevelopmental disorders worldwide. The placenta is the crucial interface between mother and fetus. Prenatal alcohol exposure (PAE) has been shown to alter placental structure and expression of genes in bulk placental tissue samples, but prior studies have not examined effects on placental cell-type composition or taken cell-type into consideration in transcriptome analyses. METHODS: We leveraged an existent placenta single-cell RNA-seq dataset to perform cell-type deconvolution of bulk placental RNA-seq data from 35 heavy drinking pregnant women and 33 controls in a prospective birth cohort in Cape Town, South Africa. We used bivariate analyses and multivariable adjusted linear regression models to assess the relation of PAE on inferred placental cell-type proportions. We also examined differential expression of inflammatory response genes and PAE, using multivariable adjusted linear models. RESULTS: Deconvolution analyses showed heterogeneous placenta cell-type composition in which stromal (27 %), endothelial (26 %) and cytotrophoblasts (18 %) were the predominant cell-types. PAE around conception was associated with a higher proportion of Hofbauer cells (B = 0.51, p = 0.035) in linear models adjusted for maternal age, infant sex, and gestational age. Among the 652 inflammatory genes examined, 35 were differential expressed in alcohol exposed placentas (FDR p < 0.05). CONCLUSIONS: Our findings suggest that heavy alcohol exposure during pregnancy can influence the proportion of fetal placental villi macrophages (Hofbauer cells) and increased expression of inflammatory genes. Future studies are needed to further characterize these effects and to assess the potential functional roles of placental inflammation in FASD.


Asunto(s)
Trastornos del Espectro Alcohólico Fetal , Efectos Tardíos de la Exposición Prenatal , Femenino , Embarazo , Humanos , Placenta/metabolismo , Trastornos del Espectro Alcohólico Fetal/genética , Trastornos del Espectro Alcohólico Fetal/metabolismo , Estudios Prospectivos , RNA-Seq , Efectos Tardíos de la Exposición Prenatal/genética , Efectos Tardíos de la Exposición Prenatal/metabolismo , Sudáfrica , Etanol/toxicidad , Expresión Génica
11.
Sci Rep ; 14(1): 2687, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302628

RESUMEN

Alcohol consumption during pregnancy can result in a range of adverse postnatal outcomes among exposed children. However, identifying at-risk children is challenging given the difficulty to confirm prenatal alcohol exposure and the lack of early diagnostic tools. Placental surveys present an important opportunity to uncover early biomarkers to identify those at risk. Here, we report the first transcriptome-wide evaluation to comprehensively evaluate human placental pathways altered by fetal alcohol exposure. In a prospective longitudinal birth cohort in Cape Town, South Africa, we performed bulk tissue RNAseq in placenta samples from 32 women reporting heavy drinking during pregnancy and 30 abstainers/light drinkers. Weighted gene co-expression network analysis (WGCNA) and differential gene expression analysis were performed to assess associations between fetal alcohol exposure and placental gene expression patterns at a network-wide and single gene level, respectively. The results revealed altered expression in genes related to erythropoiesis and angiogenesis, which are implicated in established postnatal phenotypes related to alcohol exposure, including disruptions in iron homeostasis, growth, and neurodevelopment. The reported findings provide insights into the molecular pathways affected by prenatal alcohol exposure and highlight the potential of placental biomarkers for detecting and understanding the effects of alcohol on fetal development.


Asunto(s)
Placenta , Efectos Tardíos de la Exposición Prenatal , Niño , Humanos , Femenino , Embarazo , Placenta/metabolismo , Estudios Prospectivos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Sudáfrica , Etanol/farmacología , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/genética , Biomarcadores/metabolismo
12.
Infect Immun ; 81(3): 764-76, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23264051

RESUMEN

Trehalose 6,6'-dimycolate (TDM) is a cell wall glycolipid and an important virulence factor of mycobacteria. In order to study the role of TDM in the innate immune response to Mycobacterium tuberculosis, microarray analysis was used to examine gene regulation in murine bone marrow-derived macrophages in response to 90-µm-diameter polystyrene microspheres coated with TDM. A large number of genes, particularly those involved in the immune response and macrophage function, were up- or downregulated in response to these TDM-coated beads compared to control beads. Genes involved in the immune response were specifically upregulated in a myeloid differentiation primary response gene 88 (MyD88)-dependent manner. The complexity of the transcriptional response also increased greatly between 2 and 24 h. Matrix metalloproteinases (MMPs) were significantly upregulated at both time points, and this was confirmed by quantitative real-time reverse transcription-PCR (RT-PCR). Using an in vivo Matrigel granuloma model, the presence and activity of MMP-9 were examined by immunohistochemistry and in situ zymography (ISZ), respectively. We found that TDM-coated beads induced MMP-9 expression and activity in Matrigel granulomas. Macrophages were primarily responsible for MMP-9 expression, as granulomas from neutrophil-depleted mice showed staining patterns similar to that for wild-type mice. The relevance of these observations to human disease is supported by the similar induction of MMP-9 in human caseous tuberculosis (TB) granulomas. Given that MMPs likely play an important role in both the construction and breakdown of tuberculous granulomas, our results suggest that TDM may drive MMP expression during TB pathogenesis.


Asunto(s)
Factores Cordón/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Macrófagos/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Animales , Granuloma/metabolismo , Granuloma/microbiología , Humanos , Macrófagos/citología , Macrófagos/fisiología , Metaloproteinasas de la Matriz/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mycobacterium tuberculosis , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN/genética , ARN/metabolismo , Transcriptoma
14.
Nutrients ; 15(19)2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37836388

RESUMEN

Prenatal alcohol exposure (PAE) is associated with alterations in maternal and infant iron homeostasis that are consistent with changes seen in the setting of inflammation. We hypothesized that PAE leads to alterations in the placental expression of genes related to iron metabolism and inflammation that play functional roles in the teratogenic effects of alcohol on iron homeostasis. A total of 126 heavy-drinking women (≥1 oz (30 mL) absolute alcohol/day (~1.67 standard drinks/day) or women reporting binge drinking (≥2 drinks/occasion)) and 80 control women (<0.5 oz AA per day, no binging) in Cape Town, South Africa were interviewed prenatally regarding demographics, and alcohol, smoking, and drug use around conception and during pregnancy. Prenatal/maternal and infant hemoglobin and ferritin were measured. Whole-transcriptome RNA sequencing analysis was performed on flash-frozen transplacental tissue samples. Gene sets related to iron metabolism (n = 398) and inflammation (n = 467) were constructed by searching the Molecular Signatures Database for related ontology terms. Principal component analysis (PCA) yielded 59 factors for each theme. In multivariable regression models, PAE was related to 2 iron metabolism PCA factors (PCs) and 5 inflammation PCs, among which 2 iron metabolism and 4 inflammation factors were related to at least 1 key maternal or infant iron outcome. In causal inference analyses based on marginal structural models and the product method, the alterations in the expression profile of genes with functions in immune cell regulation, cytokine activity, angiogenesis, hematopoiesis, and ubiquitous cell processes appeared to partially mediate the relation of prenatal drinking frequency (days/week) around conception to a lower maternal hemoglobin-to-log(ferritin) ratio (proportion mediation = 51.35%). These findings suggest that placental inflammation may be partly responsible for the differences in alcohol-related iron homeostasis patterns between pregnant and non-pregnant adults.


Asunto(s)
Placenta , Efectos Tardíos de la Exposición Prenatal , Lactante , Adulto , Femenino , Humanos , Embarazo , Placenta/metabolismo , Sudáfrica , Consumo de Bebidas Alcohólicas/efectos adversos , Hierro/metabolismo , Ferritinas/metabolismo , Etanol , Inflamación , Hemoglobinas/metabolismo , Vitaminas , Homeostasis , Expresión Génica
15.
Am J Clin Nutr ; 114(3): 1107-1122, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34091657

RESUMEN

BACKGROUND: Prenatal alcohol exposure (PAE) is associated with postnatal iron deficiency (ID), which has been shown to exacerbate deficits in growth, cognition, and behavior seen in fetal alcohol spectrum disorders. However, the mechanisms underlying PAE-related ID remain unknown. OBJECTIVES: We aimed to examine biochemical measures of iron homeostasis in the mother, placenta, neonate, and 6.5-month-old infant. METHODS: In a prenatally recruited, prospective longitudinal birth cohort in South Africa, 206 gravidas (126 heavy drinkers and 80 controls) were interviewed regarding alcohol, cigarette, and drug use and diet at 3 prenatal visits. Hemoglobin, ferritin, and soluble transferrin receptor (sTfR) were assayed twice during pregnancy and urinary hepcidin:creatinine was assayed once. Infant ferritin and hemoglobin were measured at 2 weeks and 6.5 months and sTfR was measured at 6.5 months. Histopathological examinations were conducted on 125 placentas and iron transport assays (iron regulatory protein-2, transferrin receptor-1, divalent metal transporter-1, ferroportin-1, and iron concentrations) were conducted on 63. RESULTS: In multivariable regression models, prenatal drinking frequency (days/week) was related to higher maternal hepcidin and to sequestration of iron into storage at the expense of erythropoiesis in mothers and neonates, as evidenced by a lower hemoglobin (g/dL)-to-log(ferritin) (ug/L) ratio [mothers: raw regression coefficient (ß) = -0.21 (95% CI: -0.35 to -0.07); neonates: ß = -0.15 (95% CI: -0.24 to -0.06)]. Drinking frequency was also related to decreased placental ferroportin-1:transferrin receptor-1 (ß = -0.57 for logged values; 95% CI: -1.03 to -0.10), indicating iron-restricted placental iron transport. At 6.5 months, drinking frequency was associated with lower hemoglobin (ß = -0.18; 95% CI: -0.33 to -0.02), and increased prevalences of ID (ß = 0.09; 95% CI: 0.02-0.17) and ID anemia (IDA) (ß = 0.13; 95% CI: 0.04-0.23). In causal inference analyses, the PAE-related increase in IDA was partially mediated by decreased neonatal hemoglobin:log(ferritin), and the decrease in neonatal hemoglobin:log(ferritin) was partially mediated by decreased maternal hemoglobin:log(ferritin). CONCLUSIONS: In this study, greater PAE was associated with an unfavorable profile of maternal-fetal iron homeostasis, which may play mechanistic roles in PAE-related ID later in infancy.


Asunto(s)
Trastornos del Espectro Alcohólico Fetal/diagnóstico , Homeostasis/efectos de los fármacos , Hierro/metabolismo , Placenta/efectos de los fármacos , Adolescente , Adulto , Consumo de Bebidas Alcohólicas , Fumar Cigarrillos , Estudios de Cohortes , Femenino , Trastornos del Espectro Alcohólico Fetal/patología , Humanos , Lactante , Recién Nacido , Análisis Multivariante , Placenta/metabolismo , Embarazo , Adulto Joven
16.
Int J Cardiol ; 333: 119-126, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-33607192

RESUMEN

BACKGROUND: Heart failure (HF), the dominant form of cardiovascular disease in Africans, is mainly due to hypertension, rheumatic heart disease and cardiomyopathy. Cardiomyopathies pose a great challenge because of poor prognosis and high prevalence in low- and middle-income countries (LMICs). Little is known about the etiology and outcome of cardiomyopathy in Africa. Specifically, the role of myocarditis and the genetic causes of cardiomyopathy are largely unidentified in Africans. METHOD: The African Cardiomyopathy and Myocarditis Registry Program (the IMHOTEP study) is a pan-African multi-centre, hospital-based cohort study, designed with the primary aim of describing the clinical characteristics, genetic causes, prevalence, management and outcome of cardiomyopathy and myocarditis in children and adults. The secondary aim is to identify barriers to the implementation of evidence-based care and provide a platform for trials and other intervention studies to reduce morbidity and mortality in cardiomyopathy. The registry consists of a prospective cohort of newly diagnosed (i.e., incident) cases and a retrospective (i.e., prevalent) cohort of existing cases from participating centres. Patients with cardiomyopathy and myocarditis will be subjected to a standardized 3-stage diagnostic process. To date, 750 patients have been recruited into the multi-centre pilot phase of the study. CONCLUSION: The IMHOTEP study will provide comprehensive and novel data on clinical features, genetic causes, prevalence and outcome of African children and adults with all forms of cardiomyopathy and myocarditis in Africa. Based on these findings, appropriate strategies for management and prevention of the cardiomyopathies in LMICs are likely to emerge.


Asunto(s)
Cardiomiopatías , Miocarditis , Adulto , África/epidemiología , Cardiomiopatías/diagnóstico , Cardiomiopatías/epidemiología , Cardiomiopatías/genética , Niño , Estudios de Cohortes , Humanos , Miocarditis/diagnóstico , Miocarditis/epidemiología , Miocarditis/terapia , Estudios Prospectivos , Sistema de Registros , Estudios Retrospectivos
17.
Virchows Arch ; 453(2): 203-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18642028

RESUMEN

Autopsy of a stillborn neonate with hypochondrogenesis revealed severe cardiac abnormalities and extensive diverticulosis of the proximal region of the small intestine. Visceral ramifications are unusual in hypochondrogenesis; they may reflect heterogeneity of the intramolecular defect in the COL2A1 gene that codes for the achondrogenesis type II-hypochondrogenesis spectrum of disorders.


Asunto(s)
Intestino Delgado/anomalías , Osteocondrodisplasias/patología , Autopsia , Colágeno Tipo II , Femenino , Humanos , Recién Nacido , Mortinato
18.
Med Mycol Case Rep ; 19: 38-40, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29379704

RESUMEN

We present a 27-year-old lady with HIV-1 infection who died due to rapidly worsening respiratory failure one day after commencing amphotericin B deoxycholate therapy for cryptococcal meningitis. Chest x-ray appearances were consistent with pneumocystis pneumonia but post mortem examination showed evidence of severe necrotizing cryptococcal pneumonia. Cryptococcal pneumonia is an underrecognized condition and should be considered in the differential of patients with HIV-1 infection and low CD4 count who develop respiratory symptoms.

19.
J Neurol Neurosurg Psychiatry ; 78(12): 1320-4, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17470469

RESUMEN

OBJECTIVE: To report the nature of stroke in patients infected with human immunodeficiency virus (HIV) in a region with high HIV seroprevalence and describe HIV associated vasculopathy. METHODS: Patients with first ever stroke, infected with HIV and prospectively included in the stroke register of the Groote Schuur Hospital/University of Cape Town stroke unit were identified and reviewed. RESULTS: Between 2000 and 2006, 67 of the 1087 (6.1%) stroke patients were HIV infected. Of these, 91% (n = 61) were younger than 46 years. Cerebral infarction occurred in 96% (n = 64) of the HIV positive patients and intracerebral haemorrhage in 4% (n = 3). HIV infected young stroke patients did not demonstrate hypertension, diabetes, hyperlipidaemia or smoking as significant risk factors for ischaemic stroke. Infection as a risk factor for stroke was significantly more common in HIV positive patients (p = 0.018, OR 6.4, CI 3.1 to 13.2). In 52 (81%) patients with ischaemic stroke, an aetiology was determined. Primary aetiologies comprised infectious meningitides/vasculitides in 18 (28%) patients, coagulopathy in 12 (19%) patients and cardioembolism in nine (14%) patients. Multiple aetiologies were present in seven (11%) patients with ischaemic stroke. HIV associated vasculopathy was identified in 13 (20%) patients. The HIV associated vasculopathy manifested either extracranially (seven patients) as total or significant carotid occlusion or intracranially (six patients) as medium vessel occlusion, with or without fusiform aneurysmal dilation, stenosis and vessel calibre variation. CONCLUSION: Investigation of HIV infected patients presenting with stroke will determine an aetiology in the majority of patients. In our cohort, 20% of patients demonstrated evidence of an HIV associated vasculopathy.


Asunto(s)
Infecciones por VIH/epidemiología , Accidente Cerebrovascular/epidemiología , Adulto , Aneurisma/complicaciones , Aneurisma/epidemiología , Encéfalo/irrigación sanguínea , Encéfalo/patología , Estenosis Carotídea/complicaciones , Estenosis Carotídea/epidemiología , Hemorragia Cerebral/epidemiología , Hemorragia Cerebral/etiología , Hemorragia Cerebral/patología , Infarto Cerebral/epidemiología , Infarto Cerebral/etiología , Infarto Cerebral/patología , Coagulación Intravascular Diseminada/complicaciones , Coagulación Intravascular Diseminada/epidemiología , Embolia/complicaciones , Embolia/epidemiología , Femenino , Cardiopatías/complicaciones , Cardiopatías/epidemiología , Humanos , Masculino , Meningitis Meningocócica/complicaciones , Meningitis Meningocócica/epidemiología , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Sistema de Registros , Factores de Riesgo , Sudáfrica/epidemiología , Accidente Cerebrovascular/etiología
20.
Eur J Gastroenterol Hepatol ; 19(2): 93-5, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17272991

RESUMEN

Hepatic granulomas were present in 3.7% of liver biopsies from a 6-year Greek study. The majority of cases were due to autoimmune disease (primary biliary cirrhosis), followed by sarcoidosis and idiopathic causes. Infections were infrequent. This profile is similar to series from the USA, Ireland and Scotland. It contrasts dramatically with series from Turkey and Saudi Arabia where infectious aetiologies form the majority of cases, and autoimmune cases are not reported. Tuberculosis and schistosomiasis are the most prevalent infections. The patient sex and age differ strikingly in some series. The series were tabulated for easy comparison.


Asunto(s)
Granuloma/etiología , Hepatopatías/etiología , Enfermedades Autoinmunes/complicaciones , Humanos , Cirrosis Hepática Biliar/complicaciones , Sarcoidosis/complicaciones
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