Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
1.
Stem Cells ; 40(4): 371-384, 2022 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-35284915

RESUMEN

CD133 is a transmembrane protein that mainly localizes to the plasma membrane in hematopoietic/neural stem cells and cancer stem cells. Although CD133 also localizes to the cytoplasm and is degraded through autophagy, the precise mechanisms responsible for the autophagic degradation of endosomal CD133 currently remain unknown. We demonstrated that endosomal CD133 has unique properties for cell homeostasis. Endosomal CD133 is degraded through p62/SQSTM1-mediated selective autophagy. However, in low basal autophagic cells, such as SK-N-DZ and SH-SY5Y cells, endosomal CD133 accumulates at the pericentrosomal region and conversely suppresses autophagy. Endosomal CD133 also asymmetrically distributes to the pericentrosomal region and induces unequal autophagic activity between 2 daughter cells during cytokinesis in SK-N-DZ and TGW cells. In addition, the asymmetric distribution of pericentrosomal CD133 endosomes and nuclear ß-catenin cooperatively suppresses autophagic activity against p62 in SK-N-DZ cells. Thus, the present study suggests that the asymmetric distribution of pericentrosomal CD133 endosomes induces the symmetry breaking of autophagic activity during cytokinesis in cooperation with nuclear ß-catenin.


Asunto(s)
Neuroblastoma , beta Catenina , Antígeno AC133 , Autofagia , Citocinesis , Endosomas/metabolismo , Humanos , Neuroblastoma/metabolismo , beta Catenina/metabolismo
2.
Thorax ; 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35474029

RESUMEN

BACKGROUND: Multiple serotypes of pneumococci have epidemiological and clinical implications, such as the emergence of non-vaccine serotypes and the acquisition of antimicrobial resistance. Prevalence of multiple serotypes of pneumococci in adults and their risk factors are not known. METHODS: We enrolled adult patients from age ≥15 years with radiologically confirmed pneumonia in four hospitals across Japan. Pneumococcal pneumonia was defined with a pneumococcal bacterial density of ≥104/mL in sputum by lytA quantitative PCR, and serotypes were determined. Pneumonias with a single serotype were categorised as single-serotype pneumococcal pneumonia and with two or more serotypes as multiple-serotype pneumococcal pneumonia. Multivariable logistic regression was used to assess the risk factors. RESULTS: 3470 patients (median age 77 years, IQR 65-85) were enrolled. Pneumococcal pneumonia was identified in 476 (18.3%, n=2605) patients. Multiple serotypes were detected in 42% of them. Risk of having multiple serotypes was low among patients who had received 23-valent pneumococcal polysaccharide vaccine (PPSV23) vaccines (adjusted OR 0.51 (95% CI 0.27 to 0.94)). Proportion of non-PCV7 PPSV23 serotypes in overall distribution of multiple serotypes was 67.4% (n=324/481) compared with 46.4% (n=128/276) in that of single serotypes (p=0.001). Serotypes 5, 9N/9L, 10A, 12/22/46, 17F and 35F were associated with multiple-serotype pneumonia, and serotypes 6A/6B, 23F, 11 and 6C/6D were associated with single-serotype pneumonia. Proportion of more invasive serotypes (serotypes 1, 5, 7F, 8) was significantly higher in multiple-serotype pneumonia (p=0.001). CONCLUSIONS: Multiple serotypes of pneumococci are common in sputum of adult patients with pneumonia. The risk of multiple-serotype pneumococcal pneumonia is lower than that of single-serotype pneumococcal pneumonia among PPSV23-vaccinated patients. TRIAL REGISTRATION NUMBER: UMIN000006909.

3.
J Autoimmun ; 126: 102775, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34864633

RESUMEN

Primary biliary cholangitis (PBC) is a chronic cholestatic autoimmune liver disease that appears to be strongly influenced by genetic factors. Recently, an international meta-analysis of genome-wide association studies (GWAS) identified CC-Motif Chemokine Receptor-6 (CCR6) and FGFR1 Oncogene-Partner (FGFR1OP) as PBC-susceptibility genes. However, the lead single nucleotide polymorphisms (SNPs) of CCR6/FGFR1OP showed low linkage disequilibrium with each other in East Asian and European populations. Additionally, the primary functional variants and the molecular mechanisms responsible for PBC-susceptibility remain unclear. Here, among the PBC-susceptibility SNPs identified by high-density association mapping in our previous meta-GWAS (Patients: n = 10,516; healthy controls: n = 20,772) within the CCR6/FGFR1OP locus, rs9459874 and rs1012656 were identified as primary functional variants. These functional variants accounted for the effects of GWAS-identified lead SNPs in CCR6/FGFR1OP. Additionally, the roles of rs9459874 and rs1012656 in regulating FGFR1OP transcription and CCR6 translation, respectively, were supported by expression quantitative trait loci (eQTL) analysis and gene editing technology using the CRISPR/Cas9 system. Immunohistochemistry showed higher expression of CCR6 protein in the livers of patients with PBC than in those of a non-diseased control. In conclusion, we identified primary functional variants in CCR6/FGFR1OP and revealed the molecular mechanisms by which these variants confer PBC-susceptibility in an eQTL-dependent or -independent manner. The approach in this study is applicable for the elucidation of the pathogenesis of other autoimmune disorders in which CCR6/FGFR1OP is known as a susceptibility locus, as well as PBC.


Asunto(s)
Estudio de Asociación del Genoma Completo , Cirrosis Hepática Biliar , Proteínas Proto-Oncogénicas/genética , Pueblo Asiatico , Predisposición Genética a la Enfermedad , Humanos , Cirrosis Hepática Biliar/genética , Polimorfismo de Nucleótido Simple , Receptores CCR6/genética
4.
Artículo en Japonés | MEDLINE | ID: mdl-34986641

RESUMEN

The emergence and dissemination of drug-resistant Gram-negative bacilli have been recognized as a serious health concern in worldwide. The isolation rates of Extended-Spectrum ß-lactamases (ESBL) and AmpC ß-lactamases (AmpC) producing gram negative rods are increasing in our hospital. In the present study, we evaluate the availability of the antimicrobial resistance testing by the direct disc methods using AmpC/ESBL differential discs. One hundred and ten strains of Enterobacterales were isolated during the observation period, of which 19 strains (17%) were ESBL-positive and 6 strains (5%) were AmpC-positive. The positive and negative coincidence rate between direct disc methods and standard disc methods were 100%. We conclude that the direct disc method is a useful and rapid detection method for ESBL and AmpC from blood culture samples.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Enterobacteriaceae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/métodos , Antibacterianos/farmacología , Proteínas Bacterianas , Cultivo de Sangre , Bacterias Gramnegativas , beta-Lactamasas
5.
J Clin Microbiol ; 56(5)2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29444834

RESUMEN

The lack of reliable diagnostic tests for detecting vaccine serotype pneumococcal pneumonia (VTPP) remains a challenging issue in pneumococcal vaccine studies. This study assessed the performances of high-throughput nanofluidic PCR-based pneumococcal serotyping and quantification assay methods using sputum samples (the nanofluidic sputum quantitative PCR [Sp-qPCR] assay) to diagnose 13-valent pneumococcal conjugate VTPP compared with the performance of the serotype-specific urinary antigen detection (UAD) assay using urine samples. Adult pneumonia patients from Japan were enrolled in this study between September 2012 and August 2014. Sputum samples were subjected to the nanofluidic Sp-qPCR assay, quantitatively cultured, and serotyped by the Quellung reaction (SpQt). Urine samples were tested by the UAD method. The diagnostic performances of these tests were assessed using composite reference standards and Bayesian latent class models (BLCMs). Among 244 total patients, 27 (11.1%) tested positive with the UAD assay, while 16 (6.6%) and 34 (13.9%) tested positive with the SpQt and nanofluidic Sp-qPCR assays, respectively, with a cutoff value of ≥104 DNA copies/ml, which showed the maximum value of the Youden index. Using BLCMs, the estimated prevalence for VTPP was 12.9%, and the nanofluidic Sp-qPCR assay demonstrated the best performance (sensitivity, 90.2%; specificity, 96.9%), followed by UAD (sensitivity, 75.6%; specificity, 97.9%) and SpQt (sensitivity, 45.8%; specificity, 99.5%). However, when a higher cutoff value of ≥107 DNA copies/ml was applied, the performance of UAD became comparable to that of Sp-qPCR. The vaccine serotype-specific pneumococcal DNA load in sputum among UAD-positive patients was 3 logs higher than that among UAD-negative patients (P = 0.036). The nanofluidic Sp-qPCR assay may be accurate and useful for detecting VTPP among adults.


Asunto(s)
Microfluídica , Vacunas Neumococicas/aislamiento & purificación , Neumonía Neumocócica/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Serotipificación/métodos , Esputo/microbiología , Streptococcus pneumoniae/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Antígenos Bacterianos/orina , Teorema de Bayes , Femenino , Humanos , Japón/epidemiología , Análisis de Clases Latentes , Masculino , Persona de Mediana Edad , Vacunas Neumococicas/genética , Neumonía Neumocócica/epidemiología , Prevalencia , Estudios Prospectivos , Sensibilidad y Especificidad , Serotipificación/normas , Esputo/química , Streptococcus pneumoniae/genética , Adulto Joven
6.
Emerg Infect Dis ; 23(8): 1404-1408, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28726625

RESUMEN

In Afghanistan, childhood deaths from pneumonia are high. Among 639 children at 1 hospital, the case-fatality rate was 12.1%, and 46.8% of pneumococcal serotypes detected were covered by the 13-valent vaccine. Most deaths occurred within 2 days of hospitalization; newborns and malnourished children were at risk. Vaccination could reduce pneumonia and deaths.


Asunto(s)
Neumonía/epidemiología , Adolescente , Afganistán/epidemiología , Niño , Preescolar , Femenino , Hospitalización , Humanos , Lactante , Recién Nacido , Masculino , Mortalidad , Oportunidad Relativa , Vacunas Neumococicas/inmunología , Neumonía/etiología , Neumonía/mortalidad , Neumonía/prevención & control , Riesgo , Factores de Riesgo , Serogrupo , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/inmunología
7.
J Hum Genet ; 61(9): 793-6, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27193219

RESUMEN

In this study, associations between invasive cervical cancer and four cervical cancer susceptibility loci (rs13117307 at 4q12, rs8067378 at 17q12, and rs4282438 and rs9277952 at 6p21.32) in the Han Chinese population were investigated in a Japanese population. Human leukocyte antigen (HLA)-DPB1 alleles were also investigated for their association with cervical cancer risk in the Japanese population. After receiving written informed consent, 214 unrelated Japanese women with invasive cervical cancer and 288 cancer-free Japanese women were recruited, and DNA samples were obtained (study protocol approved by Institutional Review Board of Nagasaki University). Of the four single-nucleotide polymorphisms, rs8067378 showed a significant association with invasive cervical cancer (P=0.0071). Under a recessive model, the minor allele G of rs8067378 contributed to the risk of invasive cervical cancer (odds ratio=2.92, 95% confidence interval=1.40-6.36; P=0.0021). No association was detected between HLA-DPB1 alleles and cervical cancer risk in the Japanese population. In conclusion, we show for the first time, to the best of our knowledge, that an association between increased risk of invasive cervical cancer and rs8067378 in the Han Chinese population is replicated in a Japanese population. In addition, Japanese women with the GG genotype of rs8067378 are a candidate high-risk group for invasive cervical carcinoma.


Asunto(s)
Pueblo Asiatico/genética , Cromosomas Humanos Par 17 , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Adulto , Anciano , Alelos , Estudios de Casos y Controles , China , Femenino , Genotipo , Cadenas beta de HLA-DP/genética , Humanos , Japón , Persona de Mediana Edad , Invasividad Neoplásica , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Riesgo
8.
Am J Hum Genet ; 91(4): 721-8, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23000144

RESUMEN

For the identification of susceptibility loci for primary biliary cirrhosis (PBC), a genome-wide association study (GWAS) was performed in 963 Japanese individuals (487 PBC cases and 476 healthy controls) and in a subsequent replication study that included 1,402 other Japanese individuals (787 cases and 615 controls). In addition to the most significant susceptibility region, human leukocyte antigen (HLA), we identified two significant susceptibility loci, TNFSF15 (rs4979462) and POU2AF1 (rs4938534) (combined odds ratio [OR] = 1.56, p = 2.84 × 10(-14) for rs4979462, and combined OR = 1.39, p = 2.38 × 10(-8) for rs4938534). Among 21 non-HLA susceptibility loci for PBC identified in GWASs of individuals of European descent, three loci (IL7R, IKZF3, and CD80) showed significant associations (combined p = 3.66 × 10(-8), 3.66 × 10(-9), and 3.04 × 10(-9), respectively) and STAT4 and NFKB1 loci showed suggestive association with PBC (combined p = 1.11 × 10(-6) and 1.42 × 10(-7), respectively) in the Japanese population. These observations indicated the existence of ethnic differences in genetic susceptibility loci to PBC and the importance of TNF signaling and B cell differentiation for the development of PBC in individuals of European descent and Japanese individuals.


Asunto(s)
Cirrosis Hepática Biliar/genética , Transactivadores/genética , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Linfocitos B , Estudios de Casos y Controles , Diferenciación Celular/genética , Femenino , Sitios Genéticos/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Antígenos HLA/genética , Humanos , Masculino , Persona de Mediana Edad , Subunidad p50 de NF-kappa B/genética , Polimorfismo Genético , Factor de Transcripción STAT4/genética , Factor de Necrosis Tumoral alfa/genética , Población Blanca/genética , Adulto Joven
9.
Rheumatology (Oxford) ; 54(4): 660-5, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25240611

RESUMEN

OBJECTIVE: The aim of this study was to analyse the role of circulating cleaved IL-1ß in patients with FMF. METHODS: We enrolled 20 patients with FMF (5 males and 15 females), 22 patients with RA (4 males and 18 females) and 22 healthy controls (6 males and 16 females). Serum levels of serum amyloid A (SAA) were measured by ELISA. We also determined whether IL-1ß was present as the cleaved form (p17) in the sera of FMF patients by immunoblotting using anti-cleaved IL-1ß antibody. RESULTS: Although SAA concentrations were elevated in the sera, there was no significant difference in these concentrations between FMF patients and RA patients. Immunoblot analysis demonstrated that the cleaved form of IL-1ß (p17) was present in sera from FMF patients during febrile attack periods, but not in healthy controls. Bands representing the cleaved form of IL-1ß were not detected in serum from FMF patients at non-febrile attack periods or remission periods under colchicine treatment. The amounts of cleaved IL-1ß (p17) were significantly higher in patients with FMF compared with those in patients with RA in the inflammatory phase. CONCLUSION: The cleaved form of IL-1ß is a valuable biomarker for monitoring disease activity and response to colchicine treatment in patients with FMF. It might be useful to discriminate FMF from other non-IL-1ß-mediated inflammatory disorders.


Asunto(s)
Fiebre Mediterránea Familiar/metabolismo , Interleucina-1beta/metabolismo , Proteína Amiloide A Sérica/metabolismo , Adulto , Anciano , Artritis Reumatoide/metabolismo , Pueblo Asiatico , Biomarcadores/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Immunoblotting , Masculino , Persona de Mediana Edad
10.
Tohoku J Exp Med ; 233(2): 73-7, 2014 06.
Artículo en Inglés | MEDLINE | ID: mdl-24835548

RESUMEN

Autoinflammatory diseases represent an expanding spectrum of genetic and non-genetic inflammatory diseases characterized by recurrent episodes of fever and systemic inflammation, affecting joints, skin and serosal surfaces. Familial Mediterranean fever (FMF) is the most common autosomal recessive hereditary autoinflammatory disease. Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is an autosomal dominant hereditary autoinflammatory disease. They share some clinical manifestations such as a periodic fever and skin rash. We present here the association of FMF with TRAPS in a systemic lupus erythematosus (SLE) patient. A 54-year-old SLE patient with recurrent attacks of fever, arthritis, and skin rashes was referred to our hospital. She had been diagnosed with lupus nephritis at 19 years old. Her lupus nephritis was controlled by steroid treatments; however, since childhood she has suffered from recurrent episodes of periodic fever, abdominal pain, arthritis, and erythematous skin rashes. An initial diagnosis of FMF was suspected based on the genetic analysis, showing the compound heterozygous L110P/E148Q mutations in the MEFV gene that is responsible for FMF. Her symptoms responded to colchicine, but the febrile attacks were not completely resolved. Therefore, genetic testing for TRAPS was performed. The results revealed a heterozygous T61I mutation in the TNFRSF1A gene that encodes tumor necrosis factor-α receptor and is responsible for TRAPS. The patient was diagnosed with overlapping FMF and TRAPS, in addition to SLE. This is the first report of SLE associated with both FMF and TRAPS.


Asunto(s)
Fiebre Mediterránea Familiar/complicaciones , Enfermedades Autoinflamatorias Hereditarias/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Secuencia de Bases , Biopsia , Proteínas del Citoesqueleto/genética , Análisis Mutacional de ADN , Fiebre Mediterránea Familiar/genética , Fiebre Mediterránea Familiar/patología , Femenino , Fiebre , Enfermedades Autoinflamatorias Hereditarias/genética , Enfermedades Autoinflamatorias Hereditarias/patología , Humanos , Riñón/patología , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/patología , Nefritis Lúpica/complicaciones , Nefritis Lúpica/patología , Persona de Mediana Edad , Datos de Secuencia Molecular , Pirina , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Adulto Joven
11.
Mod Rheumatol ; 24(1): 212-6, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24261781

RESUMEN

Familial Mediterranean fever (FMF) is an autoinflammatory disorder characterized by recurrent febrile polyserositis and arthritis. Although accompanying seronegative spondyloarthropathy has been reported in FMF, coexistence with rheumatoid arthritis (RA) is very rare. This case report describes a Japanese female RA patient who presented with periodic fever. Genetic analysis revealed compound heterozygous mutations in exon 2 and 3 of the MEFV gene (E148Q/G304R/P369S/R408Q). The patient was successfully treated with colchicine with 3-year follow-up.


Asunto(s)
Artritis Reumatoide/complicaciones , Fiebre Mediterránea Familiar/complicaciones , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/genética , Colchicina/uso terapéutico , Proteínas del Citoesqueleto/genética , Fiebre Mediterránea Familiar/tratamiento farmacológico , Fiebre Mediterránea Familiar/genética , Femenino , Humanos , Persona de Mediana Edad , Mutación , Pirina , Resultado del Tratamiento
13.
J Autoimmun ; 47: 25-33, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23953137

RESUMEN

HLA locus contains immune-related genes and genetically regulates immune responses against both foreign- and self-antigens in humans. Inhibitor of κB-like protein (IκBL), encoded by HLA-linked NFKBIL1, is a protein of unknown function, while genetic variations in NFKBIL1 are known to associate with the susceptibility to inflammatory and/or autoimmune diseases. In this study, we found that IκBL suppressed exon exclusion in alternative splicing of human immune-related genes such as CD45. Yeast-two-hybrid screening and immunoprecipitation assay revealed molecular association of IκBL with CLK1, a serine/threonine and tyrosine kinase, which plays a role in the alternative splicing. Unexpectedly, we found that the regulation of alternative splicing in CD45 by IκBL was independent from the kinase activity of CLK1. On the other hand, it was demonstrated that an SR protein, ASF/SF2, bound both IκBL and CLK1 at the RNA-recognition motifs of ASF/SF2, implying a competition of IκBL and CLK1 on SR protein. In addition, IκBL was found to regulate the CLK1-dependent synthesis of M2 RNA, a splice variant of influenza A virus M gene. These observations suggest a functional involvement of IκBL in the regulation of alternative splicing in both human and viral genes, which is a novel link of HLA locus to the regulation of immunity and infection in humans.


Asunto(s)
Empalme Alternativo , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase II/inmunología , Virus de la Influenza A/genética , Antígenos Comunes de Leucocito/genética , Proteínas de la Matriz Viral/genética , Proteínas Adaptadoras Transductoras de Señales , Animales , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Células COS , Chlorocebus aethiops , Células HEK293 , Células HeLa , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Inflamación/genética , Inflamación/inmunología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/inmunología , Estructura Terciaria de Proteína , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/inmunología , Interferencia de ARN , ARN Interferente Pequeño , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Factores de Empalme Serina-Arginina
14.
Immunogenetics ; 64(1): 15-29, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21744114

RESUMEN

Toll-like receptor 2 (TLR2) plays an important role in the recognition of a variety of pathogenic microbes. In the present study, we compared polymorphisms of TLR2 locus in two closely related old world monkey species, rhesus monkey (Macaca mulatta) and Japanese monkey (Macaca fuscata). By nucleotide sequencing of the third exon of TLR2 gene from 21 to 35 respective individuals, we could assign 17 haplotype combinations of 17 coding SNPs of ten non-synonymous and seven synonymous substitutions. A non-synonymous substitution at codon position 326 appeared to be differentially fixed in each species, asparagine for M. mulatta whereas tyrosine for M. fuscata, and may contribute to certain functional properties because it locates in the region contributing to ligand binding and interaction with dimerization partner of TLR2-TLR1 heterodimeric complex. Although TLR2 alleles have diverged to similar extent in both species, they have evolved in significantly different ways; TLR2 of M. fuscata has undergone purifying selection while the membrane-proximal part of the extracellular domain of M. mulatta TLR2 exhibits higher rates of non-synonymous substitutions, indicating a trace of Darwinian positive selection.


Asunto(s)
Macaca mulatta/genética , Macaca/genética , Polimorfismo de Nucleótido Simple , Selección Genética , Receptor Toll-Like 2/genética , Alelos , Secuencia de Aminoácidos , Animales , Evolución Molecular , Células HEK293 , Humanos , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Receptor Toll-Like 2/química
15.
Malar J ; 11: 168, 2012 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-22594374

RESUMEN

BACKGROUND: In areas mesoendemic for malaria transmission, symptomatic individuals play a significant role as reservoirs for malaria infection. Understanding the pathogenesis of symptomatic malaria is important in devising tools for augmenting malaria control. In this study, the effect of TLR9 polymorphisms on susceptibility to symptomatic malaria was investigated among Ghanaian children. METHODS: Four hundred and twenty nine (429) healthy Ghanaian children, aged three to eleven years (3-11 years), were enrolled into a cohort study and actively followed up for symptomatic malaria for one year. Four TLR9 single nucleotide polymorphisms (SNPs) namely: rs187084 (C-1486 T), rs5743836(C-1237 T), rs352139 (G + 1174A) and rs352140 (G + 2848A) were genotyped by direct sequencing, and their attributable and relative risks for symptomatic malaria determined. TLR9 haplotypes were inferred using the PHASE software and analysed for the risk of symptomatic malaria. A luciferase assay was performed to investigate whether the TLR9 haplotypes influence TLR9 promoter activity. RESULTS: The rs352139 GG genotype showed a significantly increased relative risk of 4.8 for symptomatic malaria (P = 0.0024) and a higher mean parasitaemia (P = 0.04). Conversely, the rs352140 GG genotype showed a significantly reduced relative risk of 0.34 (P = 0.048). TLR9 haplotypes analyses showed that TTAG haplotype was significantly associated with reduced relative risk of 0.2 for symptomatic malaria (P = 4×10⁻6) and a lower mean parasitaemia (0.007), while CTGA haplotype had an increased relative risk of 3.3 (P = 0.005). Functional luciferase reporter gene expression assay revealed that the TTA haplotype had a significantly higher promoter activity than the CCG, CTG and TCG haplotypes. CONCLUSIONS: Taken together, these findings indicate a significant association of TLR9 gene polymorphisms with symptomatic malaria among Ghanaian children in Dangme-West district.


Asunto(s)
Predisposición Genética a la Enfermedad , Malaria/genética , Malaria/inmunología , Polimorfismo de Nucleótido Simple , Receptor Toll-Like 9/genética , Niño , Preescolar , Estudios de Cohortes , Genotipo , Ghana , Haplotipos , Humanos , Estudios Longitudinales , Análisis de Secuencia de ADN
16.
PLoS Negl Trop Dis ; 16(5): e0010414, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35613181

RESUMEN

Community-acquired bacterial bloodstream infections are caused by diverse pathogens with changing antimicrobial-resistance patterns. In low-middle income countries in Southeast Asia, where dengue fever is endemic and a leading cause of fever, limited information is available about bacterial bloodstream infections due to challenges of implementing a blood culture service. This study describes bacterial bloodstream pathogens and antimicrobial-resistance patterns in Metro Manila, the Philippines. We aimed to identify the proportion of patients with a positive blood culture, the bacteria isolated and their antimicrobial resistance patterns, and the clinical characteristics of these patients, in this dengue endemic area. We conducted a prospective observational study in a single hospital enrolling febrile patients clinically suspected of having a community-acquired bacterial bloodstream infection between 1st July 2015 and 30th June 2019. Each patient had a blood culture and additional diagnostic tests according to their clinical presentation. We enrolled 1315 patients and a significant positive blood culture was found in 77 (5.9%) including Staphylococcus aureus (n = 20), Salmonella enterica Typhi (n = 18), Escherichia coli (n = 16), Streptococcus pneumoniae (n = 3) and Burkholderia pseudomallei (n = 2). Thirty-four patients had meningococcal disease diagnosed by culture (n = 8) or blood PCR (n = 26). Additional confirmed diagnoses included leptospirosis (n = 177), dengue virus infection (n = 159) and respiratory diphtheria (n = 50). There were 79 (6.0%, 95%CI 4.8%-7.4%) patients who died within 28 days of enrollment. Patients with a positive blood culture were significantly more likely to die than patients with negative culture (15.2% vs 4.4%, P<0.01). Among S. aureus isolates, 11/20 (55%) were methicillin-resistant (MRSA) and ST30: USA1100 was dominant sequence type (88.9%). Antimicrobial-susceptibility was well preserved in S. enterica Typhi. Among hospitalized patients with clinically suspected community-acquired bacterial bloodstream infection in Metro Manila, the Philippines, 5.9% had a blood culture confirmed infection of whom 15.6% died. S. aureus, including a significant number of MRSA (USA1100 clones), S. enterica Typhi, E.coli and Neisseria meningitidis were frequently identified pathogens.


Asunto(s)
Bacteriemia , Infecciones Comunitarias Adquiridas , Dengue , Salmonella enterica , Sepsis , Infecciones Estafilocócicas , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Dengue/complicaciones , Farmacorresistencia Bacteriana , Escherichia coli , Fiebre/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana , Filipinas/epidemiología , Salmonella typhi , Sepsis/microbiología , Staphylococcus aureus
17.
Parasitol Res ; 108(4): 807-14, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20978790

RESUMEN

To mimic a human malaria infection in the endemic condition, two strains of mice (Balb/c and CBA) were infected and treated several times to generate so-called semi-immune status. As previously reported, neither mice (Balb/c and CBA) strain showed cerebral malaria, even in the susceptible C57BL/6 (B6). The significant difference between the mice strains in our previous study was the rate of destruction of uninfected red blood cells (uRBCs) at infection. After the established repeated cycles of infection and treatment and the final challenge with 10(4) Plasmodium berghei ANKA until minimum Hb, Balb/c and CBA mice were sacrificed. The spleen, liver, brain, kidney, lung, heart, and muscle were removed, stained with hematoxylin-eosin and analyzed with light microscopy. Previous observation suggested that Balb/c destroyed uRBC at much higher rate than the other strains although the parasitemia was very low. Pathological investigation carried out in this study revealed that this destruction was mainly contributed by the uRBCs as no parasite sequestration was observed in any of the organs. However, malaria pigment deposition was observed in spleen and liver of all the semi-immune mice strains. This histopathological study in the severe malaria anemia model, which is difficult to conduct in humans, will be helpful in taking into account different responses to malaria infection when designing therapeutic interventions and vaccine studies.


Asunto(s)
Malaria/patología , Plasmodium berghei/patogenicidad , Estructuras Animales/patología , Animales , Modelos Animales de Enfermedad , Eritrocitos/parasitología , Histocitoquímica , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos CBA , Microscopía , Enfermedades de los Roedores/patología
18.
PLoS One ; 16(11): e0258936, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34723977

RESUMEN

The advanced platelet parameters Immature Platelet Fraction and Immature Platelet Fraction Count have been implemented in clinical practice as measures of thrombopoietic activity, mainly in hematologic disorders that cause thrombocytopenia. The purpose of this observational study was to examine thrombopoiesis as reflected by these 2 new CBC parameters in patients infected with dengue. The study was conducted in infectious disease referral hospital in Metro Manila, the Philippines. We enrolled hospitalized patients at admission who were diagnosed with acute dengue or community acquired bacterial infection (CABI). Immature Platelet Fraction (IPF) and Immature Platelet Fraction Count were evaluated at admission and during hospitalization. A total of 606 patients were enrolled from May 1, 2017 to June 1, 2018. The participants consisted of 152 patients with dengue infection, 180 confirmed CABI, and 274 suspected CABI patients. At admission, the percent IPF (IPF%) of the patients with dengue was significantly higher than that of the confirmed CABI patients (median 3.7% versus 1.9%; p <0.001). In a time course evaluation, there was no significant difference of IPF% between the patients with dengue infection and the confirmed CABI patients in the febrile phase (median 1.9% versus 2.4%; p = 0.488), however, the IPF% of the patients with dengue infection increased to be significantly higher than that of the confirmed CABI patients in the critical phase (median 5.2% versus 2.2%; p <0.001). Our study elucidated the unique characteristics and time-course trends of IPF percent and number (IPF#) in the patients with dengue infection. IPF% and IPF# are potentially valuable parameters in dengue and further investigation is required for the optimal use in clinical practice.


Asunto(s)
Recuento de Células Sanguíneas , Plaquetas/patología , Dengue/sangre , Infecciones Bacterianas/sangre , Infecciones Comunitarias Adquiridas/sangre , Femenino , Hospitalización , Humanos , Masculino , Recuento de Plaquetas , Trombocitopenia/sangre , Factores de Tiempo , Adulto Joven
19.
Sci Rep ; 11(1): 8676, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33883610

RESUMEN

A birth cohort study was conducted in Khan Hoa Province, central Vietnam between 2009 and 2012 to determine the seroprevalence of hepatitis B virus (HBV) in pregnant women and their children, and associated risk factors. We enrolled 1987 pregnant women with their babies at the birth phase, and 12.6% (95% confidence interval [CI]: 11.1-14.0) of mothers were hepatitis B surface antigen (HBsAg)+. At 2-year follow-up phase, 1339 (67.4%) children were enrolled of whom 76.6% completed hepatitis B vaccines (HepB) and 1.9% (95% CI: 1.2-2.7) were HBsAg+. When mothers were hepatitis B e antigen (HBeAg)+, 28.3% of children have got infected even with complete HepB. HBV infection in mothers, hepatitis B surface antibody (anti-HBs antibody) below the seroprotective level in children, and mothers with pre-pregnancy low body mass index were associated with HBV infection in children. Meanwhile, HBV infection in children, older maternal age, no or incomplete doses of HepB, and boys were associated with anti-HBs antibody below the seroprotective level in children. Our birth cohort study determined a low rate of congenital HBV infection and associated risk factors in Vietnam, however further studies are needed to advance prevention including anti-viral therapy in pregnant women at high risk.


Asunto(s)
Vacunas contra Hepatitis B/uso terapéutico , Hepatitis B/prevención & control , Vacunación Masiva , Complicaciones Infecciosas del Embarazo/prevención & control , Adolescente , Adulto , Preescolar , Femenino , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Lactante , Recién Nacido , Masculino , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Estudios Prospectivos , Factores de Riesgo , Vietnam/epidemiología , Adulto Joven
20.
J Exp Med ; 199(12): 1709-18, 2004 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-15210746

RESUMEN

Recently, encouraging AIDS vaccine trials in macaques have implicated cytotoxic T lymphocytes (CTLs) in the control of the simian human immunodeficiency virus SHIV89.6P that induces acute CD4(+) T cell depletion. However, none of these vaccine regimens have been successful in the containment of replication of the pathogenic simian immunodeficiency viruses (SIVs) that induce chronic disease progression. Indeed, it has remained unclear if vaccine-induced CTL can control SIV replication. Here, we show evidence suggesting that vaccine-induced CTLs control SIVmac239 replication in rhesus macaques. Eight macaques vaccinated with DNA-prime/Gag-expressing Sendai virus vector boost were challenged intravenously with SIVmac239. Five of the vaccinees controlled viral replication and had undetectable plasma viremia after 5 wk of infection. CTLs from all of these five macaques rapidly selected for escape mutations in Gag, indicating that vaccine-induced CTLs successfully contained replication of the challenge virus. Interestingly, analysis of the escape variant selected in three vaccinees that share a major histocompatibility complex class I haplotype revealed that the escape variant virus was at a replicative disadvantage compared with SIVmac239. These findings suggested that the vaccine-induced CTLs had "crippled" the challenge virus. Our results indicate that vaccine induction of highly effective CTLs can result in the containment of replication of a highly pathogenic immunodeficiency virus.


Asunto(s)
Vacunas contra el SIDA/inmunología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/fisiología , Linfocitos T Citotóxicos/inmunología , Replicación Viral/inmunología , Animales , Modelos Animales de Enfermedad , Genes env , Genes nef , Humanos , Macaca mulatta , Masculino , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda