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1.
JCI Insight ; 6(19)2021 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-34622805

RESUMEN

Common variable immunodeficiency (CVID) is characterized by profound primary antibody defects and frequent infections, yet autoimmune/inflammatory complications of unclear origin occur in 50% of individuals and lead to increased mortality. Here, we show that circulating bacterial 16S rDNA belonging to gut commensals was significantly increased in CVID serum (P < 0.0001), especially in patients with inflammatory manifestations (P = 0.0007). Levels of serum bacterial DNA were associated with parameters of systemic immune activation, increased serum IFN-γ, and the lowest numbers of isotype-switched memory B cells. Bacterial DNA was bioactive in vitro and induced robust host IFN-γ responses, especially among patients with CVID with inflammatory manifestations. Patients with X-linked agammaglobulinemia (Bruton tyrosine kinase [BTK] deficiency) also had increased circulating bacterial 16S rDNA but did not exhibit prominent immune activation, suggesting that BTK may be a host modifier, dampening immune responses to microbial translocation. These data reveal a mechanism for chronic immune activation in CVID and potential therapeutic strategies to modify the clinical outcomes of this disease.


Asunto(s)
Agammaglobulinemia/sangre , Inmunodeficiencia Variable Común/sangre , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Microbioma Gastrointestinal/genética , Enfermedades Genéticas Ligadas al Cromosoma X/sangre , Inflamación/sangre , Adolescente , Adulto , Agammaglobulinemia/inmunología , Anciano , Anemia Hemolítica Autoinmune/sangre , Anemia Hemolítica Autoinmune/complicaciones , Anemia Hemolítica Autoinmune/inmunología , Linfocitos B/inmunología , Traslocación Bacteriana , Niño , Preescolar , Inmunodeficiencia Variable Común/complicaciones , Inmunodeficiencia Variable Común/inmunología , ADN Bacteriano/inmunología , ADN Ribosómico/inmunología , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/inmunología , Granuloma/sangre , Granuloma/complicaciones , Granuloma/inmunología , Humanos , Cambio de Clase de Inmunoglobulina , Memoria Inmunológica/inmunología , Inflamación/inmunología , Interferón gamma/sangre , Enfermedades Pulmonares Intersticiales/sangre , Enfermedades Pulmonares Intersticiales/complicaciones , Enfermedades Pulmonares Intersticiales/inmunología , Masculino , Persona de Mediana Edad , Poliendocrinopatías Autoinmunes/sangre , Poliendocrinopatías Autoinmunes/complicaciones , Poliendocrinopatías Autoinmunes/inmunología , Púrpura Trombocitopénica Idiopática/sangre , Púrpura Trombocitopénica Idiopática/complicaciones , Púrpura Trombocitopénica Idiopática/inmunología , Esplenomegalia/sangre , Esplenomegalia/complicaciones , Esplenomegalia/inmunología , Adulto Joven
2.
J Infect Dis ; 221(5): 786-795, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31630194

RESUMEN

Accurate malaria diagnosis is foundational for control and elimination, and Haiti relies on histidine-rich protein 2 (HRP2)-based rapid diagnostic tests (RDTs) identifying Plasmodium falciparum in clinical and community settings. In 2017, 1 household and 2 easy-access group surveys tested all participants (N = 32 506) by conventional and high-sensitivity RDTs. A subset of blood samples (n = 1154) was laboratory tested for HRP2 by bead-based immunoassay and for P. falciparum 18S rDNA by photo-induced electron transfer polymerase chain reaction. Both RDT types detected low concentrations of HRP2 with sensitivity estimates between 2.6 ng/mL and 14.6 ng/mL. Compared to the predicate HRP2 laboratory assay, RDT sensitivity ranged from 86.3% to 96.0% between tests and settings, and specificity from 90.0% to 99.6%. In the household survey, the high-sensitivity RDT provided a significantly higher number of positive tests, but this represented a very small proportion (<0.2%) of all participants. These data show that a high-sensitivity RDT may have limited utility in a malaria elimination setting like Haiti.


Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Malaria Falciparum/diagnóstico , Malaria Falciparum/transmisión , Plasmodium falciparum/genética , Plasmodium falciparum/inmunología , Adolescente , Antígenos de Protozoos/sangre , Antígenos de Protozoos/inmunología , Niño , Preescolar , ADN Protozoario/sangre , ADN Protozoario/genética , ADN Ribosómico/sangre , ADN Ribosómico/genética , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Haití/epidemiología , Humanos , Lactante , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Masculino , Reacción en Cadena de la Polimerasa/métodos , Proteínas Protozoarias/sangre , Proteínas Protozoarias/inmunología , Sensibilidad y Especificidad
3.
Parasit Vectors ; 12(1): 495, 2019 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-31640746

RESUMEN

BACKGROUND: Our study aimed to assess the diversity of the species of Anaplasmataceae in Senegal that infect animals and ticks in three areas: near Keur Momar Sarr (northern region), Dielmo and Diop (Sine Saloum, central region of Senegal), and in Casamance (southern region of Senegal). METHODS: A total of 204 ticks and 433 blood samples were collected from ruminants, horses, donkeys and dogs. Ticks were identified morphologically and by molecular characterization targeting the 12S rRNA gene. Molecular characterization of species of Anaplasmataceae infecting Senegalese ticks and animals was conducted using the 23S rRNA, 16S rRNA, rpoB and groEL genes. RESULTS: Ticks were identified as Rhipicephalus evertsi evertsi (84.3%), Hyalomma rufipes (8.3%), Hyalomma impeltatum (4.9%), R. bursa (1.5%) and R. muhsamae (0.9%). The overall prevalence of Anaplasmataceae infection in ticks was 0.9%, whereas 41.1% of the sampled animals were found infected by one of the species belonging to this family. We identified the pathogen Anaplasma ovis in 55.9% of sheep, A. marginale and A. centrale in 19.4% and 8.1%, respectively, of cattle, as well as a putative new species of Anaplasmataceae. Two Anaplasma species commonly infecting ruminants were identified. Anaplasma cf. platys, closely related to A. platys was identified in 19.8% of sheep, 27.7% of goats and 22.6% of cattle, whereas a putative new species, named here provisionally "Candidatus Anaplasma africae", was identified in 3.7% of sheep, 10.3% of goats and 8.1% of cattle. Ehrlichia canis and Anaplasma platys were identified only from dogs sampled in the Keur Momar Sarr area. Ehrlichia canis was identified in 18.8% of dogs and two R. e. evertsi ticks removed from the same sheep. Anaplasma platys was identified in 15.6% of dogs. Neither of the dogs sampled from Casamance region nor the horses and donkeys sampled from Keur Momar Sarr area were found infected by an Anaplasmataceae species. CONCLUSIONS: This study presents a summary of Anaplasmataceae species that infect animals and ticks in three areas from the northern, central and southern regions of Senegal. To our knowledge, our findings demonstrate for the first time the presence of multiple Anaplasmataceae species that infect ticks and domestic animals in Senegal. We recorded two potentially new species commonly infecting ruminants named here provisionally as Anaplasma cf. platys and "Candidatus Anaplasma africae". However, E. canis was the only species identified and amplified from ticks. None of the other Anaplasmataceae species identified in animals were identified in the tick species collected from animals.


Asunto(s)
Infecciones por Anaplasmataceae/veterinaria , Anaplasmataceae/clasificación , Anaplasmataceae/genética , Animales Domésticos/microbiología , Garrapatas/microbiología , Infecciones por Anaplasmataceae/microbiología , Animales , Animales Domésticos/parasitología , Bovinos , Chaperonina 60/genética , ADN Ribosómico/sangre , ADN Ribosómico/química , ADN Ribosómico/aislamiento & purificación , ARN Polimerasas Dirigidas por ADN/genética , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/parasitología , Perros , Equidae/microbiología , Equidae/parasitología , Femenino , Variación Genética , Cabras , Enfermedades de los Caballos/microbiología , Enfermedades de los Caballos/parasitología , Caballos , Masculino , Filogenia , ARN Ribosómico/genética , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Rumiantes/microbiología , Rumiantes/parasitología , Senegal , Alineación de Secuencia/veterinaria , Ovinos , Infestaciones por Garrapatas/complicaciones , Infestaciones por Garrapatas/veterinaria
4.
Sci Rep ; 9(1): 7536, 2019 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-31101866

RESUMEN

Circulating microbial dysbiosis is associated with chronic liver disease including nonalcoholic steatohepatitis and alcoholic liver disease. In this study, we evaluated whether disease-specific alterations of circulating microbiome are present in patients with cirrhosis and hepatocellular carcinoma (HCC), and their potential as diagnostic biomarkers for HCC. We performed cross-sectional metagenomic analyses of serum samples from 79 patients with HCC, 83 with cirrhosis, and 201 matching healthy controls, and validated the results in the same number of subjects. Serum bacterial DNA was analyzed using high-throughput pyrosequencing after amplification of the V3-V4 hypervariable regions of 16S rDNA. Blood microbial diversity was significantly reduced in HCC, compared with cirrhosis and control. There were significant differences in the relative abundances of several bacterial taxa that correlate with the presence of HCC, thus defining a specific blood microbiome-derived metagenomic signature of HCC. We identified 5 microbial gene markers-based model which distinguished HCC from controls with an area under the receiver-operating curve (AUC) of 0.879 and a balanced accuracy of 81.6%. In the validation, this model accurately distinguished HCC with an AUC of 0.875 and an accuracy of 79.8%. In conclusion, circulating microbiome-based signatures may be potential biomarkers for the detection HCC.


Asunto(s)
Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/diagnóstico , ADN Bacteriano/sangre , Disbiosis/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/diagnóstico , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/microbiología , Estudios Transversales , ADN Ribosómico/sangre , ADN Ribosómico/genética , Disbiosis/microbiología , Femenino , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/microbiología , Neoplasias Hepáticas/microbiología , Masculino , Metagenoma/genética , Microbiota/genética , Persona de Mediana Edad , ARN Ribosómico 16S/genética , República de Corea
5.
Carcinogenesis ; 40(8): 975-978, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-30859204

RESUMEN

Disruption of ribosomal DNA (rDNA) has been linked to a variety of diseases in humans, including carcinogenesis. To evaluate the associations between rDNA copy number (CN) and risk of lung cancer, we measured 5.8S and 18S rDNA CN in the peripheral blood of 229 incident lung cancer cases and 1:1 matched controls from a nested case-control study within a prospective cohort of male smokers. There was a dose-response relationship between quartiles of both 18S and 5.8S rDNA CN and risk of lung cancer (odds ratio [OR], 95% confidence interval [CI]: 18S: 1.0 [ref]; 1.2 [0.6-2.1]; 1.8 [1.0-3.4]; 2.3 [1.3-4.1; Ptrend = 0.0002; 5.8S: 1.0 [ref]; 1.6 [0.8-2.9]; 2.2 [1.1-4.2]; 2.6 [1.3-5.1]; Ptrend = 0.0001). The associations between rDNA CN and lung cancer risk were similar when excluding cases diagnosed within 5 years of follow-up, and when stratifying by heavy (>20 cigarettes per day) and light smokers (≤20 cigarettes per day). We are the first to report that rDNA CN may be associated with future risk of lung cancer. To further elucidate the relationship between rDNA and lung cancer, replication studies are needed in additional populations, particularly those that include non-smokers.


Asunto(s)
Carcinogénesis/genética , Variaciones en el Número de Copia de ADN/genética , ADN Ribosómico/genética , Neoplasias Pulmonares/genética , Anciano , Carcinogénesis/patología , Estudios de Casos y Controles , Estudios de Cohortes , ADN Ribosómico/sangre , Suplementos Dietéticos , Finlandia/epidemiología , Humanos , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/dietoterapia , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Fumar/efectos adversos , Fumar/sangre , alfa-Tocoferol/administración & dosificación , beta Caroteno/administración & dosificación
6.
Microbiome ; 7(1): 25, 2019 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-30764863

RESUMEN

BACKGROUND: Increased autoreactive antibodies have been reported in HIV disease; however, the mechanism accounting for autoantibody induction in HIV remains unknown. RESULTS: Herein, we show that seasonal influenza vaccination induces autoantibody production (e.g., IgG anti-nuclear antibody (ANA) and anti-double-stranded DNA antibody (anti-dsDNA)) in some viral-suppressed antiretroviral therapy (ART)-treated HIV+ subjects, but not in healthy controls. These autoantibodies were not derived from antigen-specific B cells but from activated "bystander" B cells analyzed by single-cell assay and by study of purified polyclonal ANAs from plasma. To explore the mechanism of autoantibody generation in HIV+ subjects, plasma level of microbial products, gene expression profile of B cells, and B cell receptor (BCR) repertoires were analyzed. We found that autoantibody production was associated with increased plasma level of microbial translocation; the patients with high autoantibodies had skewed B cell repertoires and upregulation of genes related to innate immune activation in response to microbial translocation. By analyzing circulating microbial 16S rDNA in plasma, the relative abundance of Staphylococcus was found to be associated with autoantibody production in HIV+ subjects. Finally, we found that injection of heat-killed Staphylococcus aureus promoted germinal center B cell responses and autoantibody production in mice, consistent with the notion that autoantibody production in HIV+ patients is triggered by microbial products. CONCLUSIONS: Our results showed that translocation of Staphylococcus can promote B cell activation through enhancing germinal center response and induces autoantibody production. It uncovers a potential mechanism linking microbial translocation and autoimmunity in HIV+ disease and provides a strong rationale for targeting Staphylococcus to prevent autoantibody production.


Asunto(s)
Autoanticuerpos/metabolismo , Traslocación Bacteriana , Infecciones por VIH/inmunología , Vacunas contra la Influenza/inmunología , Staphylococcus/fisiología , Animales , Autoanticuerpos/sangre , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Modelos Animales de Enfermedad , Centro Germinal/inmunología , Células Hep G2 , Humanos , Inmunidad Innata , Gripe Humana/prevención & control , Activación de Linfocitos , Masculino , Ratones , Análisis de la Célula Individual , Staphylococcus/genética , Staphylococcus/inmunología , Regulación hacia Arriba
7.
Artículo en Inglés | MEDLINE | ID: mdl-32039040

RESUMEN

Rheumatoid Arthritis (RA) has been increasingly associated with perturbations to the microbial communities that reside in and on the body (the microbiome), in both human and animal studies. To date, such studies have mainly focused on the microbial communities that inhabit the gut and oral cavity. Mounting evidence suggests that microbial DNA can be detected in the blood circulation using a range of molecular methods. This DNA may represent an untapped pool of biomarkers that have the potential to report on changes to the microbiome of distant sites (e.g., example, the gut and oral cavity). To this end, through amplification and sequencing of the bacterial 16S rRNA variable region four, we evaluated the presence and identity of microbial DNA in blood samples obtained from RA patients (both prior to and 3 months following the instigation of treatment) in comparison to a small number of healthy control subjects and samples obtained from patients with ankylosing spondylitis (AS) and psoriatic arthritis (PA). Bacterial-derived DNA was identified in the majority of our patient samples. Taxonomic classification revealed that the microbiome community in RA was distinct from AS, PA, and the healthy state. Through analysis of paired patient samples obtained prior to and 3 months following treatment (V0 vs. V3), we found the microbiome to be modulated by treatment, and in many cases, this shift reduced the distance between these samples and the healthy control samples, suggesting a partial normalization following treatment in some patients. This effect was especially evident in seronegative arthritis patients. Herein, we provide further evidence for the existence of a blood microbiome in health and identify specific taxa modulated in disease and following treatment. These blood-derived signatures may have significant utility as disease biomarkers and suggest this area warrants further investigation.


Asunto(s)
Artritis Reumatoide/patología , Biomarcadores/sangre , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Microbioma Gastrointestinal , Microbiota , Boca/microbiología , Humanos , ARN Ribosómico 16S/genética
8.
Curr HIV Res ; 16(3): 208-215, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30062968

RESUMEN

BACKGROUND: Immune Activation (IA) has been previously documented in both pregnant (PG) and non-PG HIV-1 infected (HIV+) women as well as in HIV- uninfected PG women; the latter as a result of the fetal allograft. To determine whether the combined effects of HIV and pregnancy result in increased IA and whether IA is associated with Microbial Translocation (MT), we performed a prospective, longitudinal, controlled study during pregnancy and the postpartum (PP) period. METHODS: HIV+ PG women had biomarkers of IA and MT tested at 12-20 weeks (T1), and 24-36 weeks (T2) of pregnancy and at 6-8 weeks Postpartum (T3). HIV+, non-PG women were tested at comparable time points. HIV- PG women were tested at T1 only. HIV+ women were not started on antiretroviral therapy (ART) until T1. Biomarkers of IA assessed included: CD4DR+, CD4CD38+, CD4DR+CD38+, CD8DR+, CD8CD38+, and CD8DR+CD38+. Biomarkers of MT included LPS, sCD14, and 16SrDNA. RESULTS: 30 HIV+PG women, 18 HIV+ non-PG and 10 HIV-PG were enrolled. In the HIV+ women, there were no differences in median age, viral load, % or absolute CD4 at entry. Significant differences between T1 and T2 and between T1 and T3 were noted in CD8DR+CD38+ in HIV+PG women after ART. CD4DR+, CD4DR+CD38+, and CD8DR+ decreased post ART in HIV+PG women but a decline in IA was less evident in HIV+ non-PG. LPS decreased post ART by T3 in both HIV+PG and HIV+ non-PG groups; 16SrDNA was elevated at all time points in both groups when compared to control values, and declined post ART in the HIV+PG group. A subgroup of HIV-PG at T1 had IA and MT as evidenced by several IA markers and increased LPS. CONCLUSION: The degree of IA and MT was similar among HIV+PG and HIV+ non-PG women followed longitudinally. There was no incremental increase due to the combined effects of HIV and pregnancy. Several markers of IA and MT (LPS, 16SrDNA) decreased post ART. IA and MT occurred in a subgroup of HIV-PG women during the 1st trimester. Further study must be done to confirm whether MT consistently occurs in some healthy women during PG.


Asunto(s)
Traslocación Bacteriana , Infecciones por VIH/patología , VIH-1/crecimiento & desarrollo , Complicaciones Infecciosas del Embarazo/patología , Adolescente , Adulto , Antígenos CD/análisis , Biomarcadores/sangre , Sangre/microbiología , Sangre/virología , ADN Ribosómico/sangre , Femenino , Infecciones por VIH/microbiología , Infecciones por VIH/virología , Humanos , Lipopolisacáridos/sangre , Estudios Longitudinales , Activación de Linfocitos , Persona de Mediana Edad , Periodo Posparto , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/virología , Estudios Prospectivos , ARN Ribosómico 16S/sangre , Carga Viral , Adulto Joven
10.
Am J Trop Med Hyg ; 98(6): 1683-1691, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29557337

RESUMEN

Plasmodium falciparum histidine-rich protein 2 (PfHRP2) forms the basis of many current malaria rapid diagnostic tests (RDTs). However, the parasites lacking part or all of the pfhrp2 gene do not express the PfHRP2 protein and are, therefore, not identifiable by PfHRP2-detecting RDTs. We evaluated the performance of the SD Bioline Malaria Ag P.f/Pan RDT together with pfhrp2 variation in Madagascar. Genomic DNA isolated from 260 patient blood samples were polymerase chain reaction (PCR)-amplified for the parasite 18S rRNA and pfhrp2 genes. Post-PCR ligation detection reaction-fluorescent microsphere assay (LDR-FMA) was performed for the identification of parasite species. Plasmodium falciparum histidine-rich protein 2 amplicons were sequenced. Polymerase chain reaction diagnosis of patient samples showed that 29% (75/260) were infected and P. falciparum was present in 95% (71/75) of these PCR-positive samples. Comparing RDT and P. falciparum detection by LDR-FMA, eight samples were RDT negative but P. falciparum positive (false negatives), all of which were pfhrp2 positive. The sensitivity and specificity of the RDT were 87% and 90%, respectively. Seventy-three samples were amplified for pfhrp2, from which nine randomly selected amplicons were sequenced, yielding 13 sequences. Amplification of pfhrp2, combined with RDT analysis and P. falciparum detection by LDR-FMA, showed that there was no indication of pfhrp2 deletion. Sequence analysis of pfhrp2 showed that the correlation between pfhrp2 sequence structure and RDT detection rates was unclear. Although the observed absence of pfhrp2 deletion from the samples screened here is encouraging, continued monitoring of the efficacy of the SD Bioline Malaria Ag P.f/Pan RDT for malaria diagnosis in Madagascar is warranted.


Asunto(s)
Antígenos de Protozoos/genética , Malaria Falciparum/diagnóstico , Plasmodium falciparum/aislamiento & purificación , Proteínas Protozoarias/genética , ADN Protozoario/sangre , ADN Ribosómico/sangre , Pruebas Diagnósticas de Rutina , Humanos , Madagascar , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad
11.
Parasitology ; 144(9): 1203-1210, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28696186

RESUMEN

Babesia are intraerythrocytic parasites of importance worldwide within the fields of human and veterinary medicine, as some Babesia sp., including Babesia microti are potentially zoonotic and can cause fatal disease in both humans and animals. The aims of this study were to use a nested PCR (amplifying the 18S rRNA gene) to determine the presence and species of Babesia parasite DNA found in blood (n = 47) and spleen (n = 47) samples collected from Eurasian badgers (Meles meles) in Scotland. The results showed 28/47 (59·6%) blood and 14/47 (29·8%) spleen samples tested positive for the presence of Babesia DNA. Initial sequence analysis of the Babesia DNA identified three distinct sequence types (submitted to GenBank KX528553, KX528554 and KX528555), which demonstrated ⩾99% identity to Babesia sp. parasites previously identified in badgers in Spain (KT223484 and KT223485). Phylogenetic analysis showed that the three isolates are closely related to Babesia annae, B. microti and other Piroplasmida species found in wildlife. Further sequence analysis of the samples demonstrated that the badgers were routinely infected with more than one parasite isolate and there was also evidence of genetic recombination between the Babesia parasite isolates (submitted to GenBank KY250472 - KY250477).


Asunto(s)
Babesia/aislamiento & purificación , Babesiosis/parasitología , ADN Protozoario/sangre , Mustelidae/parasitología , Bazo/parasitología , Animales , Babesia/genética , Babesiosis/epidemiología , ADN Protozoario/aislamiento & purificación , ADN Ribosómico/sangre , Humanos , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Escocia/epidemiología , Análisis de Secuencia de ADN/veterinaria
12.
Mutat Res ; 791-792: 49-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27648955

RESUMEN

A single exposure to ionizing radiation (IR) results in an elevated cell-free DNA (cfDNA) content in the blood plasma. In this case, the cfDNA concentration can be a marker of the cell death in the organism. However, a chronic exposure to a low-dose IR enhances both the endonuclease activity and titer of antibodies to DNA in blood plasma, resulting in a decrease of the total concentration of circulating cfDNA in exposed people. In this case, the total cfDNA concentration should not be considered as a marker of the cell death in an exposed body. We assumed that a pool of the cfDNA circulating in the exposed people contains DNA fragments, which are resistant to a double-strand break formation in the environment of the elevated plasma endonuclease activity, and can be accumulated in the blood plasma. In order to test this hypothesis, we studied the content of GC-rich sequences (69%GC) of the transcribed region of human ribosomal repeat (rDNA), as well as the content of AT-rich repeat (63%AT) of satellite III (1q12) in the cfDNA samples obtained from 285 individuals. We have found that a chronic exposure to gamma-neutron radiation (N=88) and tritium ß-radiation (N=88) evokes an increase of the rDNA content (RrDNA index) and a decrease of the satellite III content (RsatIII index) in the circulating cfDNA as compared with the cfDNA of non-exposed people (N=109). Such index that simultaneously displays both the increase of rDNA content and decrease of satellite III content in the cfDNA (RrDNA/RsatIII) can be recommended as a marker of chronic processes in the body that involve the elevated cell death rate and/or increased blood plasma endonuclease activity.


Asunto(s)
Partículas beta/efectos adversos , ADN Ribosómico/sangre , ADN Satélite/sangre , Rayos gamma/efectos adversos , Exposición Profesional/efectos adversos , Exposición a la Radiación/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Roturas del ADN de Doble Cadena , ADN Ribosómico/genética , ADN Satélite/genética , Relación Dosis-Respuesta en la Radiación , Secuencia Rica en GC , Humanos , Persona de Mediana Edad , Neutrones , Exposición Profesional/análisis , Dosis de Radiación , Exposición a la Radiación/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Federación de Rusia , Secuencias Repetidas en Tándem/genética , Tritio , Adulto Joven
13.
AIDS ; 30(7): 1069-74, 2016 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-27032111

RESUMEN

OBJECTIVE: Vitamin D has been linked to the immune response modulation and the integrity of the intestinal mucosal barrier. Therefore, vitamin D might be involved in bacterial translocation related to HIV infection. Our major aim was to analyze the association between plasma levels of 25-hydroxy-vitamin D [25(OH)D] and bacterial 16S ribosomal DNA (bactDNA) in 120 HIV/hepatitis c virus (HCV) coinfected patients. DESIGN: Cross-sectional study. METHODS: Plasma 25(OH)D levels were quantified by enzyme immunoassay. The vitamin D status was defined as deficient (<25 nmol/l), insufficient (25-74 nmol/l), and optimal (≥75 nmol/l) plasma levels. Plasma bactDNA levels were measured by quantitative real-time PCR. For bactDNA levels the cutoffs used were as follows: low [p75th). RESULTS: Eighteen (15%) patients had 25(OH)D deficiency, 93 (77.5%) had insufficiency and nine (7.5%) had 25(OH)D optimal values. The bactDNA levels were lower in patients with 25(OH)D at least 75 nmol/l [37 copies/µl] than in patients with 25(OH)D insufficiency [84.2 copies/µl; P = 0.042]. Conversely, low bactDNA levels (

Asunto(s)
Traslocación Bacteriana , Coinfección/complicaciones , ADN Bacteriano/sangre , Infecciones por VIH/complicaciones , Hepatitis C Crónica/complicaciones , Vitamina D/análogos & derivados , Adulto , Estudios Transversales , ADN Ribosómico/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Plasma/química , ARN Ribosómico 16S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Vitamina D/sangre
14.
Neurology ; 86(15): 1425-1432, 2016 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-26911637

RESUMEN

OBJECTIVE: To explore the effects of microglial activation on brain function and structure, and its relationship with peripheral inflammatory markers, in treated, HIV-positive individuals, using in vivo [(11)C]PBR28 PET (to measure the 18 kDa translocator protein [TSPO]). METHODS: Cognitively healthy HIV-positive individuals on suppressive antiretroviral therapy and HIV-negative individuals (controls) underwent brain [(11)C]PBR28 PET and MRI. HIV-positive patients completed neuropsychological testing and CSF testing for chemokines. The concentration of bacterial ribosomal 16sDNA in plasma was measured as a marker of microbial translocation. RESULTS: HIV-positive individuals showed global increases in TSPO expression compared to controls (corrected p < 0.01), with significant regional increases in the parietal (p = 0.001) and occipital (p = 0.046) lobes and in the globus pallidus (p = 0.035). TSPO binding in the hippocampus, amygdala, and thalamus were associated with poorer global cognitive performance in tasks assessing verbal and visual memory (p < 0.05). Increased TSPO binding was associated with increased brain white matter diffusion MRI mean diffusivity in HIV-positive individuals, a lower CD4/CD8 ratio, and both high pretreatment HIV RNA and plasma concentration ribosomal 16s DNA (p < 0.05). CONCLUSIONS: Cognitively healthy HIV-positive individuals show evidence for a chronically activated brain innate immune response and elevated blood markers of microbial translocation despite effective control of plasma viremia. Increased brain inflammation is associated with poorer cognitive performance and white matter microstructural pathology, suggesting a possible role in cognitive impairments found in some HIV-positive patients despite effective treatment.


Asunto(s)
Antirretrovirales/uso terapéutico , Encéfalo/diagnóstico por imagen , Encéfalo/inmunología , Infecciones por VIH/diagnóstico por imagen , Infecciones por VIH/inmunología , Receptores de GABA/metabolismo , Acetamidas , Adulto , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Encéfalo/efectos de los fármacos , Mapeo Encefálico , Relación CD4-CD8 , Radioisótopos de Carbono , Quimiocinas/líquido cefalorraquídeo , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Imagen de Difusión Tensora , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/psicología , Humanos , Masculino , Pruebas Neuropsicológicas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Piridinas , ARN Viral/líquido cefalorraquídeo , Radiofármacos , Receptores de GABA/genética , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/efectos de los fármacos , Sustancia Blanca/inmunología
15.
Parasitol Res ; 113(12): 4407-14, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25204728

RESUMEN

Blood and ectoparasitic ticks were collected from migratory seabirds in New Zealand, including Australasian gannets (n = 13) from two sites and red-billed gulls (n = 9) and white-fronted terns (n = 2) from a third location. Blood smears were screened for parasite presence by microscopy, while DNA from blood samples was subjected to PCR for the presence of tick-transmitted protozoan haemoparasites belonging to the order Piroplasmida. Parasites were identified by comparing small subunit ribosomal RNA (18S rDNA) gene sequences to related sequences on GenBank. Analyses indicated that nine birds were infected with unknown variants of a Babesia poelea-like parasite (recorded as genotypes I and II), while four harboured a piroplasm that was genetically similar to Babesia kiwiensis. There was no parasite stratification by bird species; both the gannets and gulls were positive for all three parasites, while the terns were positive for the B. kiwiensis-like and the B. poelea-like (genotype I) parasites. The B. kiwiensis-like parasite found in the birds was also found in two species of ticks: Carios capensis and Ixodes eudyptidis. This represents the first report of Babesia-positive ticks parasitising seabirds in New Zealand. The lack of host specificity and evidence of wide ranging distributions of the three piroplasm genotypes suggests there is a high degree of haemoparasite transmission occurring naturally between New Zealand seabird populations and species.


Asunto(s)
Babesia/clasificación , Babesiosis/parasitología , Enfermedades de las Aves/parasitología , Charadriiformes/parasitología , Migración Animal , Animales , Vectores Arácnidos/parasitología , Argasidae/parasitología , Babesia/genética , Babesiosis/epidemiología , Enfermedades de las Aves/epidemiología , Aves , Citocromos b/genética , ADN Protozoario/sangre , ADN Protozoario/química , ADN Ribosómico/sangre , ADN Ribosómico/química , Femenino , Genotipo , Ixodes/parasitología , Masculino , Nueva Zelanda/epidemiología , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN/veterinaria , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/veterinaria
16.
J Acquir Immune Defic Syndr ; 66(1): 16-24, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24378729

RESUMEN

BACKGROUND: Gut damage resulting in microbial translocation (MT) is considered a major cause of immune activation (IA) in HIV infection, but data in children are limited, particularly in the absence of antiretroviral therapy. METHODS: Sixty perinatally HIV-infected, antiretroviral therapy-naive children, aged 2-12 years, were evaluated for plasma levels of lipopolysaccharide, DNA sequences encoding bacterial 16 second ribosomal DNA (16S rDNA) and soluble CD14 concurrently with markers of CD4 and CD8 T-cell IA and immune exhaustion (IE), CD4 counts, and plasma viral load. At study entry, participants were classified into immune categories (ICs): IC1 (CD4% > 25), IC2 (CD4% 15-25), and IC3 (CD4% < 15). Age-matched HIV-uninfected children served as controls. Data were evaluated at study entry and at 12 months. RESULTS: Levels of MT, IA, and IE were increased in patients as compared with controls, were highest in patients in IC3 group, and did not change over 12 months. MT products lipopolysaccharide and 16S rDNA correlated with each other and each correlated with plasma viral load, soluble CD14, and T-cell IA and IE. There was a correlation of IA with IE. CD4 counts and percentage were inversely correlated with MT products and underlying CD4 activation. CONCLUSIONS: In a natural history cohort of HIV-infected children not on therapy, MT was more pronounced in the most severely immunocompromised patients and was associated with IA. Strategies to reduce MT may help to reduce IA and prevent CD4 depletion.


Asunto(s)
Traslocación Bacteriana , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/fisiopatología , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , Adolescente , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Niño , Preescolar , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Femenino , Infecciones por VIH/patología , Humanos , Lactante , Receptores de Lipopolisacáridos/sangre , Lipopolisacáridos/sangre , Masculino , Carga Viral
18.
Med Clin (Barc) ; 142(2): 47-52, 2014 Jan 21.
Artículo en Español | MEDLINE | ID: mdl-24120098

RESUMEN

BACKGROUND AND OBJECTIVE: Inflammatory biomarkers are increased in patients with human immunodeficiency virus (HIV) infection. Antiretroviral treatment (ART) improves some parameters but do not normalize them. The aim of this study is to determine those factors (including microbial translocation) associated with higher inflammation in HIV treated patients. PATIENTS AND METHODS: Transversal observational study. INCLUSION CRITERIA: HIV patients receiving ART with an HIV viral load (VL)<400 copies/mL. Selection of patients: consecutively between November 2011 and January 2012. Main variable: plasma levels of interleukin 6 (IL-6) and tumour necrosis factor α (TNF-α). Main explanatory variable: microbial translocation markers (16S ribosomal DNA and sCD14). Patients with IL-6 or TNF-α levels above percentile 75 (group 1) were compared with the rest of patients (group 2). Odds ratio (OR) were determined. RESULTS: Eighty-one patients were included (73% male, median age 45 years, 48% stage C). Twenty-six percent had chronic hepatitis C. Median CD4 cell was 493/mm(3) and 30% had detectable HIV VL. 16S ribosomal DNA was detected in 21% of patients. Factors associated with the higher levels of inflammatory markers were 16S ribosomal DNA (OR 77, P<.0001), sCD14 levels (P<.0001) and history of cardiovascular disease (OR 15, P<.01). In multivariate analysis, associations remained for 16S ribosomal DNA (OR 62, P<.0001) and previous cardiovascular disease (OR 25, P<.01). CONCLUSIONS: In patients with HIV infection receiving treatment, the higher levels of inflammatory markers are associated with microbial translocation and past cardiovascular events.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Traslocación Bacteriana , Citocinas/sangre , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Infecciones por VIH/sangre , Inflamación/sangre , Adulto , Anciano , Biomarcadores , Enfermedades Cardiovasculares/epidemiología , Comorbilidad , Estudios Transversales , Diabetes Mellitus/epidemiología , Dislipidemias/epidemiología , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/microbiología , Hepatitis C Crónica/sangre , Hepatitis C Crónica/epidemiología , Humanos , Inflamación/epidemiología , Inflamación/microbiología , Masculino , Persona de Mediana Edad , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Abuso de Sustancias por Vía Intravenosa/sangre , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adulto Joven
19.
PLoS One ; 8(10): e76969, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24130820

RESUMEN

BACKGROUND: Development of inflammatory bowel disease (IBD) involves the interplay of environmental and genetic factors with the host immune system. Mechanisms contributing to immune dysregulation in IBD are not fully defined. Development of novel therapeutic strategies is focused on controlling aberrant immune response in IBD. Current IBD therapy utilizes a combination of immunomodulators and biologics to suppress pro-inflammatory effectors of IBD. However, the role of immunomodulatory factors such as annexin A1 (ANXA1) is not well understood. The goal of this study was to examine the association between ANXA1 and IBD, and the effects of anti-TNF-α, Infliximab (IFX), therapy on ANXA1 expression. METHODS: ANXA1 and TNF-α transcript levels in PBMC were measured by RT PCR. Clinical follow up included the administration of serial ibdQs. ANXA1 expression in the gut mucosa was measured by IHC. Plasma ANXA1 levels were measured by ELISA. RESULTS: We found that the reduction in ANXA1 protein levels in plasma coincided with a decrease in the ANXA1 mRNA expression in peripheral blood of IBD patients. ANXA1 expression is upregulated during IFX therapy in patients with a successful intervention but not in clinical non-responders. The IFX therapy also modified the cellular immune activation in the peripheral blood of IBD patients. Decreased expression of ANXA1 was detected in the colonic mucosa of IBD patients with incomplete resolution of inflammation during continuous therapy, which correlated with increased levels of TNF-α transcripts. Gut mucosal epithelial barrier disruption was evident by increased plasma bacterial 16S levels. CONCLUSION: Loss of ANXA1 expression may support inflammation during IBD and can serve as a biomarker of disease progression. Changes in ANXA1 levels may be predictive of therapeutic efficacy.


Asunto(s)
Anexina A1/genética , Anexina A1/metabolismo , Enfermedad de Crohn/metabolismo , Progresión de la Enfermedad , Regulación de la Expresión Génica , Adulto , Anciano , Anexina A1/sangre , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Enfermedad de Crohn/sangre , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/inmunología , ADN Bacteriano/sangre , ADN Ribosómico/sangre , Femenino , Humanos , Inflamación/genética , Inflamación/metabolismo , Infliximab , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Activación de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/genética , Adulto Joven
20.
Ticks Tick Borne Dis ; 4(6): 503-5, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24050934

RESUMEN

Recent work has identified the presence of Anaplasma bovis, a tick-borne pathogen of cattle, in a previously undescribed species of tick collected from eastern rock sengis, Elephantulus myurus, in Limpopo Province, South Africa. These small insectivores are endemic to Africa and are important hosts of immature ticks, however, their role as reservoirs of tick-borne pathogens has not been investigated. In order to elucidate the role of sengis in the epidemiology of A. bovis, we screened the blood of 105 sengis from Limpopo Province, South Africa, for the presence of members of the genera Anaplasma and Ehrlichia by PCR. A total of 30/105 (28.6%) of individuals were infected with A. bovis, and nucleotide sequencing revealed the presence of a novel genetic variant of this pathogen. This represents the first evidence that sengis may be natural reservoir hosts of A. bovis.


Asunto(s)
Anaplasma/aislamiento & purificación , Anaplasmosis/epidemiología , Reservorios de Enfermedades , Ehrlichia/aislamiento & purificación , Ehrlichiosis/veterinaria , Musarañas/microbiología , Anaplasma/genética , Anaplasmosis/microbiología , Animales , Secuencia de Bases , Bovinos , ADN Bacteriano/sangre , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/sangre , ADN Ribosómico/química , ADN Ribosómico/genética , Ehrlichia/genética , Ehrlichiosis/epidemiología , Ehrlichiosis/microbiología , Femenino , Variación Genética , Masculino , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN/veterinaria , Sudáfrica/epidemiología
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