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1.
J Infect Dis ; 220(2): 195-202, 2019 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-30788508

RESUMEN

BACKGROUND: In 2015, the laboratory at the Ebola treatment center in Coyah, Guinea, confirmed Ebola virus disease (EVD) in 286 patients. The cycle threshold (Ct) of an Ebola virus-specific reverse transcription-polymerase chain reaction assay and 13 blood chemistry parameters were measured on admission and during hospitalization. Favipiravir treatment was offered to patients with EVD on a compassionate-use basis. METHODS: To reduce biases in the raw field data, we carefully selected 163 of 286 patients with EVD for a retrospective study to assess associations between potential risk factors, alterations in blood chemistry findings, favipiravir treatment, and outcome. RESULTS: The case-fatality rate in favipiravir-treated patients was lower than in untreated patients (42.5% [31 of 73] vs 57.8% [52 of 90]; P = .053 by univariate analysis). In multivariate regression analysis, a higher Ct and a younger age were associated with survival (P < .001), while favipiravir treatment showed no statistically significant effect (P = .11). However, Kaplan-Meier analysis indicated a longer survival time in the favipiravir-treated group (P = .015). The study also showed characteristic changes in blood chemistry findings in patients who died, compared with survivors. CONCLUSIONS: Consistent with the JIKI trial, this retrospective study revealed a trend toward improved survival in favipiravir- treated patients; however, the effect of treatment was not statistically significant, except for its influence on survival time.


Asunto(s)
Amidas/uso terapéutico , Antivirales/uso terapéutico , Ebolavirus/efectos de los fármacos , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Pirazinas/uso terapéutico , Adolescente , Adulto , Niño , Preescolar , Ensayos de Uso Compasivo/métodos , Femenino , Guinea , Fiebre Hemorrágica Ebola/virología , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Carga Viral/efectos de los fármacos , Adulto Joven
2.
Int J Mol Med ; 38(3): 687-702, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27430658

RESUMEN

Serrated polyposis (SPP) is characterized by the development of multiple serrated polyps and an increased predisposition to colorectal cancer (CRC). In the present study, we aimed to characterize, at a clinical and molecular level, a cohort of SPP patients with or without a family history of SPP and/or polyps/CRC (SPP-FHP/CRC). Sixty-two lesions from 12 patients with SPP-FHP/CRC and 6 patients with sporadic SPP were included. The patients with SPP-FHP/CRC presented with an older mean age at diagnosis (p=0.027) and a more heterogeneous histological pattern of lesions (p=0.032) than the patients with sporadic SPP. We identified two molecular forms of SPP-FHP/CRC, according to the preferential location of the lesions: proximal/whole-colon or distal colon. Mismatch repair (MMR) gene methylation [mutS homolog 6 (MSH6)/mutS homolog 3 (MSH3)] or loss of heterozygosity (LOH) of D2S123 (flanking MSH6) were detected exclusively in the former (p=3.0x10-7), in most early lesions. Proximal/whole­colon SPP-FHP/CRC presented a higher frequency of O-6-methylguanine-DNA methyltransferase (MGMT) methylation/LOH, microsatellite instability (MSI) and Wnt mutations (19/29 vs. 7/17; 16/23 vs. 1/14, p=2.2x10-4; 15/26 vs. 2/15, p=0.006; 14/26 vs. 4/20, p=0.02) but a lower frequency of B-raf proto-oncogene, serine/threonine kinase (BRAF) mutations (7/30 vs. 12/20, p=0.0089) than the distal form. CRC was more frequent in cases of Kirsten rat sarcoma viral oncogene homolog (KRAS)-associated proximal/whole-colon SPP-FHP/CRC than in the remaining cases (4/4 vs. 1/8, p=0.01). Thus, SPP-FHP/CRC appears to be a specific entity, presenting two forms, proximal/whole-colon and distal, which differ in the underlying tumor initiation pathways. Early MGMT and MMR gene deficiency in the former may underlie an inherited susceptibility to genotoxic stress.


Asunto(s)
Colon/patología , Pólipos del Colon/patología , Neoplasias Colorrectales/patología , Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Colon/metabolismo , Pólipos del Colon/genética , Pólipos del Colon/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Metilación de ADN , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Proteínas de Unión al ADN/genética , Salud de la Familia , Femenino , Humanos , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Proteína 3 Homóloga de MutS , Mutación , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Recto/metabolismo , Análisis de Secuencia de ADN/métodos , Proteínas Supresoras de Tumor/genética
3.
Nature ; 533(7601): 100-4, 2016 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-27147028

RESUMEN

Despite the magnitude of the Ebola virus disease (EVD) outbreak in West Africa, there is still a fundamental lack of knowledge about the pathophysiology of EVD. In particular, very little is known about human immune responses to Ebola virus. Here we evaluate the physiology of the human T cell immune response in EVD patients at the time of admission to the Ebola Treatment Center in Guinea, and longitudinally until discharge or death. Through the use of multiparametric flow cytometry established by the European Mobile Laboratory in the field, we identify an immune signature that is unique in EVD fatalities. Fatal EVD was characterized by a high percentage of CD4(+) and CD8(+) T cells expressing the inhibitory molecules CTLA-4 and PD-1, which correlated with elevated inflammatory markers and high virus load. Conversely, surviving individuals showed significantly lower expression of CTLA-4 and PD-1 as well as lower inflammation, despite comparable overall T cell activation. Concomitant with virus clearance, survivors mounted a robust Ebola-virus-specific T cell response. Our findings suggest that dysregulation of the T cell response is a key component of EVD pathophysiology.


Asunto(s)
Ebolavirus/inmunología , Fiebre Hemorrágica Ebola/inmunología , Fiebre Hemorrágica Ebola/fisiopatología , Linfocitos T/inmunología , Antígeno CTLA-4/metabolismo , Femenino , Citometría de Flujo , Guinea/epidemiología , Fiebre Hemorrágica Ebola/mortalidad , Humanos , Mediadores de Inflamación/inmunología , Estudios Longitudinales , Activación de Linfocitos , Masculino , Alta del Paciente , Receptor de Muerte Celular Programada 1/metabolismo , Sobrevivientes , Linfocitos T/metabolismo , Carga Viral
4.
Nature ; 530(7589): 228-232, 2016 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-26840485

RESUMEN

The Ebola virus disease epidemic in West Africa is the largest on record, responsible for over 28,599 cases and more than 11,299 deaths. Genome sequencing in viral outbreaks is desirable to characterize the infectious agent and determine its evolutionary rate. Genome sequencing also allows the identification of signatures of host adaptation, identification and monitoring of diagnostic targets, and characterization of responses to vaccines and treatments. The Ebola virus (EBOV) genome substitution rate in the Makona strain has been estimated at between 0.87 × 10(-3) and 1.42 × 10(-3) mutations per site per year. This is equivalent to 16-27 mutations in each genome, meaning that sequences diverge rapidly enough to identify distinct sub-lineages during a prolonged epidemic. Genome sequencing provides a high-resolution view of pathogen evolution and is increasingly sought after for outbreak surveillance. Sequence data may be used to guide control measures, but only if the results are generated quickly enough to inform interventions. Genomic surveillance during the epidemic has been sporadic owing to a lack of local sequencing capacity coupled with practical difficulties transporting samples to remote sequencing facilities. To address this problem, here we devise a genomic surveillance system that utilizes a novel nanopore DNA sequencing instrument. In April 2015 this system was transported in standard airline luggage to Guinea and used for real-time genomic surveillance of the ongoing epidemic. We present sequence data and analysis of 142 EBOV samples collected during the period March to October 2015. We were able to generate results less than 24 h after receiving an Ebola-positive sample, with the sequencing process taking as little as 15-60 min. We show that real-time genomic surveillance is possible in resource-limited settings and can be established rapidly to monitor outbreaks.


Asunto(s)
Ebolavirus/genética , Monitoreo Epidemiológico , Genoma Viral/genética , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/virología , Análisis de Secuencia de ADN/instrumentación , Análisis de Secuencia de ADN/métodos , Aeronaves , Brotes de Enfermedades/estadística & datos numéricos , Ebolavirus/clasificación , Ebolavirus/patogenicidad , Guinea/epidemiología , Humanos , Mutagénesis/genética , Tasa de Mutación , Factores de Tiempo
5.
PLoS One ; 6(10): e26265, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22039453

RESUMEN

Infection with Helicobacter pylori is the major cause for the development of peptic ulcer disease (PUD). In children, with no other etiology for the disease, this rare event occurs shortly after infection. In these young patients, habits of smoking, diet, consumption of alcohol and non-steroid anti-inflammatory drugs and stress, in addition to the genetic susceptibility of the patient, represent a minor influence. Accordingly, the virulence of the implicated H. pylori strain should play a crucial role in the development of PUD. Corroborating this, our in vitro infection assays comparing a pool of five H. pylori strains isolated from children with PUD to a pool of five other pediatric clinical isolates associated with non-ulcer dyspepsia (NUD) showed the greater ability of PUD strains to induce a marked decrease in the viability of gastric cells and to cause severe damage in the cells cytoskeleton as well as an impairment in the production/secretion of mucins. To uncover virulence features, we compared the proteome of these two groups of H. pylori strains. Two-dimensional gel electrophoresis followed by mass-spectrometry allowed us to detect 27 differentially expressed proteins between them. In addition to the presence of genes encoding well established virulence factors, namely cagA, vacAs1, oipA "on" status, homB and jhp562 genes, the pediatric ulcerogenic strains shared a proteome profile characterized by changes in the abundance of: motility-associated proteins, accounting for higher motility; antioxidant proteins, which may confer increased resistance to inflammation; and enzymes involved in key steps in the metabolism of glucose, amino acids and urea, which may be advantageous to face fluctuations of nutrients. In conclusion, the enhanced virulence of the pediatric ulcerogenic H. pylori strains may result from a synergy between their natural ability to better adapt to the hostile human stomach and the expression of the established virulence factors.


Asunto(s)
Helicobacter pylori/patogenicidad , Proteínas Bacterianas/metabolismo , Niño , Técnicas de Cocultivo , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/metabolismo , Humanos , Proteómica , Virulencia
6.
Fam Cancer ; 10(4): 623-31, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21837511

RESUMEN

In a fraction of families fulfilling the Amsterdam criteria for hereditary non-polyposis colorectal cancer, colorectal cancers are microsatellite stable and DNA mismatch repair gene (MMR) mutations are not found. These families were designated as familial colorectal cancer type X (FCCTX). We aimed to characterise a group of FCCTX families defined by the Amsterdam criteria and MSS tumours at clinical and molecular level. Twenty-four tumours from 15 FCCTX families were analysed for loss of known tumour suppressor gene (TSG) loci (APC, TP53, SMAD4 and DCC), MGMT and MMR genes promoter methylation, and also APC and KRAS somatic mutations. FCCTX families presented specific clinical features: absence of endometrial tumours, high adenoma/carcinoma ratio (1.91) and prevalence of rectal cancers (13/27, 48%). New molecular features were found: the majority of FCCTX tumours (13/18; 72%) presented TSG loss. TSG loss positive tumours presented frequent APC and KRAS somatic mutations and MGMT methylation [10/13 (77%), 7/13 (54%) and 6/11 (54%), respectively]. In TSG loss negative tumours (5/18; 28%), the same molecular events were found in 2/5 (40%), 2/5 (40%) and 1/3 (33%) tumours, respectively. Transition mutations in KRAS were more frequent among MGMT methylated tumours than in unmethylated [5/8 (63%) vs. 1/10 (10%), P = 0.03]. Although sharing similar clinical features, at least two different molecular entities should exist among FCCTX families, one whose tumours present frequent TSG loss, APC and KRAS somatic mutations, and MGMT promoter methylation, and a second, lesser predominant, with no evidence of TSG loss and rarely presenting promoter methylation.


Asunto(s)
Adenoma/genética , Carcinoma/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Genes Supresores de Tumor , Síndromes Neoplásicos Hereditarios/genética , Adulto , Anciano , Neoplasias Colorrectales Hereditarias sin Poliposis/clasificación , Metilación de ADN , Reparación de la Incompatibilidad de ADN/genética , Femenino , Humanos , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/clasificación , Proteínas Nucleares/genética , Portugal , Regiones Promotoras Genéticas/genética
7.
Helicobacter ; 16(2): 153-68, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21435094

RESUMEN

BACKGROUND: The human gastroduodenal pathogen, Helicobacter pylori, is characterized by an unusual extent of genetic heterogeneity. This dictates differences in the antigenic pattern of strains resulting in heterogeneous human humoral immune responses. Here, we examined the antigenic variability among a group of 10 strains isolated from Portuguese patients differing in age, gender, and H. pylori-associated gastric diseases. MATERIAL AND METHODS: Immunoassays were performed on two-dimensional electrophoresis gels obtained for the proteome of each strain, using a commercial pool of antibodies produced in rabbit, against the whole cell lysate of an Australian H. pylori strain. Relevant proteins were identified by mass spectrometry. RESULTS: Immunoproteomes of the Portuguese strains showed no correlation between the number of antigenic proteins or the antigenic profile, and the disease to which each strain was associated. The Heat shock protein B was the unique immunoreactive protein common to all of them. Additionally, seven proteins were found to be antigenic in at least 80% of strains: enoyl-(acyl-carrier-protein) reductase (NADH); Catalase; Flagellin A; 2 isoforms of alkyl hydroperoxide reductase; succinyl-CoA transferase subunit B; and an unidentified protein. These proteins were present in the proteome of all tested strains, suggesting that differences in their antigenicity are related to antigenic variance. CONCLUSIONS: This study showed evidence of the variability of antigenic pattern among H. pylori strains. We believe that this fact contributes to the failure of anti-H. pylori vaccines and the low accuracy of serological tests based on a low number of proteins or antigens of only one strain.


Asunto(s)
Variación Antigénica/inmunología , Helicobacter pylori/inmunología , Adolescente , Adulto , Anciano , Antígenos Bacterianos/análisis , Niño , Preescolar , Electroforesis en Gel Bidimensional , Femenino , Humanos , Inmunoensayo/métodos , Masculino , Persona de Mediana Edad , Adulto Joven
8.
Dis Colon Rectum ; 52(4): 742-5, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19404084

RESUMEN

MYH-associated polyposis is an inherited autosomal recessive disease, linked to biallelic germline MYH mutations, which predisposes to the development of multiple colorectal adenomas and cancer. The colonic and extracolonic phenotype of this syndrome is very heterogeneous. We report the case of a young male patient with an aggressive MYH-associated polyposis phenotype. He presented at aged 30 years with more than 100 colonic polyps and 4 colonic adenocarcinomas. At aged 35 years, Spigelman Stage IV duodenal adenomatosis was detected. When he was 39 years old, he developed three synchronous jejunal adenocarcinomas and a mesenteric desmoid tumor. Based on this report, we believe that screening of the entire small bowel should be recommended in MYH-associated polyposis patients, especially in those with duodenal adenomas. Similar to patients with familial adenomatous polyposis, desmoid tumors also may be part of the clinical spectrum of MYH-associated polyposis and may prove to be a significant clinical problem in patients submitted to prophylactic colectomy.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Neoplasias Colorrectales/genética , Fibromatosis Agresiva/genética , Neoplasias del Yeyuno/genética , Neoplasias Primarias Múltiples/genética , Neoplasias Peritoneales/genética , Adenocarcinoma/genética , Adenoma/genética , Adulto , ADN Glicosilasas/genética , Neoplasias Duodenales/genética , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Neoplasias Intestinales/genética , Obstrucción Intestinal/etiología , Neoplasias del Yeyuno/complicaciones , Neoplasias Hepáticas/secundario , Masculino , Mesenterio , Mutación , Fenotipo , Síndrome
9.
Acta Med Port ; 20(3): 243-7, 2007.
Artículo en Portugués | MEDLINE | ID: mdl-17868535

RESUMEN

MYH-associated polyposis (MAP) is an autosomal recessive disease associated with multiple colonic adenomas and colorectal cancer. Y165C and G382D MYH missense mutations are involved in more than 80% of cases in Caucasians and the large series published do not include patients homozygous for other mutations. We present the report of two siblings homozygous for the nonsense frameshift mutation 1103delC. The proband aged 28 presented with four colonic adenocarcinomas and 20-30 synchronous adenomas. Her sister aged 24 had 20 colonic adenomas and a severe Spigelman's III duodenal adenomatosis. Their parents, aged 60 and 51, heterozygous for the 1103delC MYH mutation, presented 5 and 2 low risk colorectal adenomas, respectively.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , ADN Glicosilasas/genética , Mutación , Adulto , Femenino , Homocigoto , Humanos , Linaje , Fenotipo , Índice de Severidad de la Enfermedad
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