RESUMEN
BACKGROUND: Cow's milk allergy (CMA) is the most common IgE-mediated food allergy and Bos d 5 is the major allergen in cow's milk proteins. More than 60% of the patients with CMA are sensitized to this protein. METHODS AND RESULTS: A recombinant protein, encoded by a synthetic gene and consisting of reassembled Bos d 5 fragments, was expressed in E. coli strain BL21 (DE3) cells and purified to homogeneity. The B5M lacked relevant IgE-reactivity and allergenic activity compared with Bos d 5 in dot-blot and basophil activation assays. T-cell proliferation experiments demonstrated that B5M preserved the main T cell epitopes of Bos d 5. Immunization of rabbits with B5M induced protective IgG antibodies that blocked the binding of patients' IgE antibodies to the wild-type allergen and inhibited the degranulation of basophils induced by Bos d 5. CONCLUSION: Thus, we developed a new strategy, which was based on rational molecular reassembly for allergen-specific immunotherapy (AIT) of CMA and food allergy.
Asunto(s)
Alérgenos/inmunología , Lipocalinas/inmunología , Hipersensibilidad a la Leche/inmunología , Leche/efectos adversos , Vacunas/inmunología , Alérgenos/química , Alérgenos/genética , Animales , Especificidad de Anticuerpos/inmunología , Basófilos/inmunología , Basófilos/metabolismo , Bovinos , Epítopos de Linfocito T/inmunología , Humanos , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Inmunoterapia , Lipocalinas/química , Lipocalinas/genética , Hipersensibilidad a la Leche/prevención & control , Unión Proteica/inmunología , Proteínas Recombinantes/química , Proteínas Recombinantes/inmunología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Vacunas/administración & dosificaciónRESUMEN
OBJECTIVES: To study the expression of adipokines in children with primary nephrotic syndrome (PNS) before and after treatment and its correlation with blood lipids, as well as the role of adipokines in PNS children with hyperlipidemia. METHODS: A total of 90 children who were diagnosed with incipient PNS or recurrence of PNS after corticosteroid withdrawal for more than 6 months were enrolled as subjects. Thirty children who underwent physical examination were enrolled as the control group. Venous blood samples were collected from the children in the control group and the children with PNS before corticosteroid therapy (active stage) and after urinary protein clearance following 4 weeks of corticosteroid therapy (remission stage). ELISA was used to measure the levels of adipokines. An automatic biochemical analyzer was used to measure blood lipid levels. RESULTS: Compared with the control group, the children with PNS had a significantly lower level of omentin-1 in both active and remission stages, and their level of omentin-1 in the active stage was significantly lower than that in the remission stage (P<0.001). For the children with PNS, the level of chemerin in the active stage was significantly higher than that in the remission stage, and the children with PNS in the active stage had a significantly higher level of chemerin than the control group (P<0.001). For the children with PNS, atherogenic index of plasma, atherogenic coefficient (AC), castelli risk index-1 (CRI-1), castelli risk index-2 (CRI-2), and non-high-density lipoprotein in the active stage were significantly higher than those in the remission stage (P<0.001), and these indices in the children with PNS in the active stage were significantly higher than those in the control group (P<0.001). The children with PNS in the remission stage had significantly higher atherogenic index of plasma, AC, CRI-1, and non-high-density lipoprotein than the control group (P<0.001). Compared with the control group, the children with PNS in the remission stage had significantly higher serum levels of total cholesterol, triglyceride, high-density lipoprotein, low-density lipoprotein, apolipoprotein B, and apolipoprotein A (P<0.01). In the children with PNS, the ratio of omentin-1 before and after corticosteroid therapy was positively correlated with that of high-density lipoprotein, 24-hour urinary protein excretion, and high-density lipoprotein/apolipoprotein A before and after treatment, and it was negatively correlated with the ratio of AC and CRI-1 before and after treatment (P<0.05). The PNS children with low omentin-1 levels in the active stage had significantly higher levels of CRI-1, CRI-2, AC, and apolipoprotein B/apolipoprotein A ratio than those with high omentin-1 levels (P<0.05). CONCLUSIONS: Omentin-1 may be associated with disease activity, dyslipidemia, and proteinuria in children with PNS. Blood lipid ratios may be more effective than traditional blood lipid parameters in monitoring early cardiovascular risk in children with PNS.
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Citocinas/metabolismo , Hiperlipidemias , Lectinas/metabolismo , Síndrome Nefrótico , Adipoquinas , Quimiocinas , Niño , Citocinas/genética , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Humanos , Lectinas/genética , Lípidos , Síndrome Nefrótico/tratamiento farmacológico , ProteinuriaRESUMEN
OBJECTIVE: To analyze the clinical and molecular characteristics of a child with very long chain acyl-CoA dehydrogenase deficiency (VLCADD). METHODS: Peripheral blood sample of the patient was collected for the extraction of genomic DNA. Next generation sequencing (NGS) was carried out for the proband. Suspected mutations were validated by Sanger sequencing. RESULTS: The patient, a 12-month-old girl, was admitted for diarrhea, vomiting, fever, poor spirit and decreased blood pressure. During the course of the disease, she also manifested hypertrophic cardiomyopathy, cardiogenic shock, elevated myocardial enzyme kinase, fever and metabolic acidosis, and had died after three days due to ventricular tachycardia and respiratory failure. Genetic testing showed that she has carried heterozygous mutations of of the ACADVL gene, namely c.664G>A (exon 8) and c.1056_1057del (exon 10). Blood screening for metabolic genetic diseases showed increased C12, C14, C16, C18, C14:1, C14:2, C16:1, C4/C3 and C8/C3, accompanied with decreased C0, C0/C16 and C8/C10. VLCADD and secondary carnitine deficiency could not be excluded, which was in keeping with the result of genetic testing. CONCLUSION: The child was diagnosed with VLCADD, which may be attributed to the compound heterozygous c.664G>A and c.1056_1057del variants of the ACADVL gene.
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Acil-CoA Deshidrogenasa de Cadena Larga/deficiencia , Síndromes Congénitos de Insuficiencia de la Médula Ósea/genética , Errores Innatos del Metabolismo Lipídico/genética , Enfermedades Mitocondriales/genética , Enfermedades Musculares/genética , Acil-CoA Deshidrogenasa de Cadena Larga/genética , Femenino , Pruebas Genéticas , Humanos , LactanteRESUMEN
OBJECTIVE: To carry out genetic testing for two families affected with cobalamin C (cblC) and establish a rapid method for the detection of a hotspot pathogenic variant c.609G>A of the MMACHC gene by using a PCR-high-resolution melting curve (PCR-HRM) method. METHODS: Genomic DNA was extracted from peripheral blood samples of the probands and their parents. Potential variants of the MMACHC gene was analyzed by Sanger sequencing. The c.609G>A variant of the MMACHC gene was screened among 100 healthy children with the PCR-HRM method. RESULTS: Sanger sequencing revealed that proband 1 carried compound heterozygous variants c.394C>T and c.609G>A of the MMACHC gene, while proband 2 carried compound heterozygous variants c.482G>A and c.609G>A of the same gene. PCR-HRM analysis of the two probands and the 100 healthy children were consistent with the Sanger sequencing. CONCLUSION: c.609G>A is a hotspot pathogenic variant of the MMACHC gene. The diagnosis of cblC may be rapidly attained through detection by PCR-HRM.
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Homocistinuria , Reacción en Cadena de la Polimerasa , Vitamina B 12 , Proteínas Portadoras/genética , Niño , ADN , Homocistinuria/diagnóstico , Homocistinuria/genética , Humanos , Mutación , Oxidorreductasas , Vitamina B 12/genéticaRESUMEN
OBJECTIVE: To analyze the molecular etiology of a Chinese child affected with dihydropyrimidinase deficiency. METHODS: Genomic DNA was extracted from peripheral blood samples of the family members. Pathogenic variant was determined by whole exome sequencing and verified by Sanger sequencing. RESULTS: The child was found to harbor homozygous c.905G>A (p.Arg302Gln) variants in exon 5 of the DPYS gene, for which her parents were both heterozygous carriers. CONCLUSION: The homozygous c.905G>A (p.Arg302Gln) variants of the DPYS gene probably underlies the dihydropyrimidinase deficiency in the child. Above result has enabled genetic counseling and prenatal diagnosis for this family.
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Amidohidrolasas/genética , Errores Innatos del Metabolismo/genética , Pueblo Asiatico/genética , Niño , Exones , Femenino , Humanos , Mutación , LinajeRESUMEN
OBJECTIVE: To detect potential mutation in a Chinese pedigree affected with congenital limb malformations. METHODS: Clinical data was collected. Genomic DNA was extracted from peripheral blood samples of family members. The zone of polarizing activity regulatory sequence (ZRS) were amplified by PCR and subjected to direct sequencing. RESULTS: Among the 13 individuals in this pedigree, there were 4 PPD patients, who were characterized by varying degrees of deformity. The female patients suffered triphalangeal thumb and preaxial polydactyly, while the male patients only had preaxial polydactyly. Only one patient had foot involvement. TA heterogeneous mutations was discovered in the ZRS (105C>G) in all patients, the same mutation was not detected in 2 healthy family members. CONCLUSION: The inheritance pattern of PPD was autosomal dominant inheritance. There was a significant variability of symptoms among family patients. The heterozygous mutation of the ZRS (105C>G) probably underlie the disease.
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Deformidades Congénitas de la Mano/genética , Deformidades Congénitas de las Extremidades/genética , Proteínas de la Membrana/genética , Polidactilia/genética , Femenino , Pruebas Genéticas , Humanos , Masculino , Linaje , Pulgar/patologíaRESUMEN
OBJECTIVE: To investigate the molecular epidemiological characteristics of norovirus (NoV) among children with acute gastroenteritis in Tianjin in 2017. METHODS: A total of 758 stool specimens were collected from the children with acute gastroenteritis possibly caused by viral infection in Tianjin Children's Hospital between January and December, 2017. Quantitative real-time RT-PCR was used for primary screening of NoV, and conventional RT-PCR was used for gene amplification, sequencing and genotype identification of the VP1 region of capsid protein in positive specimens. RESULTS: Among the 758 specimens, 241 (31.8%) were found to have GII NoV. Sequencing of the VP1 region of capsid protein in positive specimens showed that among the 241 specimens with GII NoV, 69 (28.6%) had GII.4 subtype, 51 (21.2%) had GII.3 subtype, 24 (10.0%) had GII.2 subtype, and 18 (7.5%) had other subtypes. There was a significant difference in NoV detection rate between different age groups (P=0.018), and the 1- <4 years group had the highest NoV detection rate (37.3%). There was also a significant difference in NoV detection rate across seasons (P<0.001), and there was a highest NoV detection rate in winter (48.1%). Twenty-seven children (3.6%) had co-infections with NoV and rotavirus. CONCLUSIONS: NoV is one of the major pathogens of the children with acute gastroenteritis from Tianjin in 2017. GII genotype, especially GII.4 subtype, is the prevalent strain. NoV infection is commonly seen in children less than 4 years and reaches the peak in winter. Some children are found to have co-infections with rotavirus.
Asunto(s)
Gastroenteritis , Norovirus , Infecciones por Caliciviridae , Niño , China/epidemiología , Heces , Gastroenteritis/epidemiología , Genotipo , Humanos , Epidemiología Molecular , Filogenia , ARN Viral , Análisis de Secuencia de ADNRESUMEN
OBJECTIVE: To explore the molecular etiology for a Chinese family affected with beta-ureidopropinoase deficiency. METHODS: Genomic DNA was extracted from the peripheral blood samples of family members. All exons and flanking intron regions of the UPB1 gene were amplified by PCR and detected by direct sequencing. The pathogenicity of identified mutation was analyzed using Polyphen2 and SIFT software. RESULTS: Compound heterozygous mutations of the UPB1 gene, including c.853G>A (p.A285T) and c.917-1G>A, were discovered in the proband, which were inherited respectively from his mother and father. Bioinformatics analysis suggested that this novel mutation was damaging. CONCLUSION: The compound heterozygous mutations of the UPB1 gene probably underlie the beta-ureidopropinoase deficiency in the infant. Discovery of c.853G>A also enriched the mutation spectrum of the UPB1 gene.
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Anomalías Múltiples/genética , Amidohidrolasas/deficiencia , Amidohidrolasas/genética , Pueblo Asiatico , Encefalopatías/genética , Trastornos del Movimiento/genética , Errores Innatos del Metabolismo de la Purina-Pirimidina/genética , China , Exones , Humanos , Lactante , Intrones , Mutación , LinajeRESUMEN
OBJECTIVE: To detect potential mutation in a Chinese family affected with succinic semialdehyde dehydrogenase deficiency. METHODS: Genomic DNA was extracted from the peripheral blood samples of the proband, her family members and 100 healthy controls. All exons and flanking intronic regions of the ALDH5A1 gene were amplified by PCR and subjected to direct sequencing. RESULTS: The proband was found to have compound heterozygous mutations of the ALDH5A1 gene, namely c.398_399delAA (p.N134X) and c.638G>T (p.R213L), for which her parents were both heterozygous carriers. The same mutations were not found among the 100 healthy controls. CONCLUSION: The novel mutations of the ALDH5A1 gene probably underlie the pathogenesis of the disease in the infant, which also enriched the mutation spectrum of the ALDH5A1 gene.
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Errores Innatos del Metabolismo de los Aminoácidos/genética , Discapacidades del Desarrollo/genética , Mutación , Succionato-Semialdehído Deshidrogenasa/deficiencia , Errores Innatos del Metabolismo de los Aminoácidos/etnología , Secuencia de Aminoácidos , Pueblo Asiatico/genética , Secuencia de Bases , China , Análisis Mutacional de ADN/métodos , Discapacidades del Desarrollo/etnología , Exones/genética , Salud de la Familia , Femenino , Heterocigoto , Humanos , Lactante , Intrones/genética , Masculino , Homología de Secuencia de Aminoácido , Succionato-Semialdehído Deshidrogenasa/genéticaRESUMEN
OBJECTIVE: To investigate the relationship of KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) with acute respiratory infection in children in Tianjin, China. METHODS: A total of 3 730 nasopharyngeal secretions were collected from hospitalized children with acute respiratory infection in Tianjin Children's Hospital from January 2011 to December 2013. Viral nucleic acid was extracted, and virus infection (KIPyV and WUPyV) was determined by PCR. Some KIPyV-positive and WUPyV-positive PCR products were subjected to sequencing. Sequencing results were aligned with the known gene sequences of KIPyV and WUPyV to construct a phylogenetic tree. Amplified VP1 fragments of KIPyV were inserted into the cloning vector (PUCm-T) transformed into E.â coli competent cells. Positive clones were identified by PCR and sequencing. The nucleotide sequences were submitted to GenBank. In addition, another seven common respiratory viruses in all samples were detected by direct immunofluorescence assay. RESULTS: In the 3 730 specimens, the KIPyV-positive rate was 12.14% (453/3 730) and the WUPyV-positive rate was 1.69% (63/3 730). The mean infection rate of KIPyV was significantly higher in June and July, while the mean infection rate of WUPyV peaked in February and March. Most of the KIPyV-positive or WUPyV-positive children were <3 years. The co-infections with KIPyV, WUPyV, and other respiratory viruses were observed in the children. The co-infection rate was 2.31% (86/3 730) and there were nine cases of co-infections with WUPyV and KIPyV. Thirty-five KIPyV-positive and twelve WUPyV-positive PCR products were sequenced and the alignment analysis showed that they had high homology with the known sequences (94%-100% vs 95%-100%). The VP1 gene sequences obtained from two KIPyV strains in this study were recorded in GenBank with the accession numbers of KY465925 and KY465926. CONCLUSIONS: For some children with acute respiratory infection in Tianjin, China, the acute respiratory infection may be associated with KIPyV and WUPyV infections. KIPyV infection is common in summer, and WUPyV infection in spring. The epidemic strains in Tianjin have a high homology with those in other regions.
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Poliomavirus/aislamiento & purificación , Infecciones del Sistema Respiratorio/virología , Enfermedad Aguda , Adolescente , Niño , Femenino , Humanos , Masculino , Epidemiología Molecular , Poliomavirus/genética , Infecciones por Polyomavirus/epidemiologíaRESUMEN
OBJECTIVE: To explore the value of urine gas chromatography-mass spectrometry (GC-MS) in the screening of children at risk of inherited metabolic diseases (IMD), and to identify the disease spectrum of IMD and the clinical characteristics of children with IMD. METHODS: The clinical data of 15 851 children at risk of IMD who underwent urine GC-MS in the Tianjin Children's Hospital between February 2012 and December 2016 were retrospectively analyzed. RESULTS: In the 15 851 children, 5 793 (36.55%) were detected to have metabolic disorders. A total of 117 (0.74%) children were confirmed to have IMD, including 77 cases of methylmalonic acidemia (65.8%). The clinical manifestations of confirmed cases in the neonatal period mainly included jaundice, metabolic acidosis, abnormal muscular tension, feeding difficulty, poor response, and lethargy or coma. The clinical manifestations of confirmed cases in the non-neonatal period mainly included delayed mental and motor development, metabolic acidosis, convulsion, recurrent vomiting, and anemia. CONCLUSIONS: GC-MS is an effective method for the screening for IMD in children at risk. Methylmalonic acidemia is the most common IMD. The clinical manifestations of IMD are different between the confirmed cases in the neonatal and non-neonatal periods.
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Errores Innatos del Metabolismo/diagnóstico , Acidosis/etiología , Adolescente , Errores Innatos del Metabolismo de los Aminoácidos/complicaciones , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Niño , Preescolar , Discapacidades del Desarrollo/etiología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Lactante , Recién Nacido , Masculino , Errores Innatos del Metabolismo/complicaciones , Estudios Retrospectivos , RiesgoRESUMEN
OBJECTIVE: To detect human bocavirus (HBoV) and investigate its genetic and evolutionary characteristics in children with acute respiratory infection in Tianjin, China. METHODS: A total of 1,259 samples of nasopharyngeal aspirates were collected from children with a confirmed diagnosis of acute respiratory infection between January and December, 2012. Viral nucleic acid was extracted, HBoV was detected by real-time quantitative PCR, and the gene segments of nucleocapsid protein of HBoV in positive samples were amplified by PCR. Several products were randomly selected and sequenced.The sequence obtained was compared with the known sequence of HBoV, and a phylogenetic analysis was performed. All the samples were examined to detect for other common respiratory tract viruses. RESULTS: Among the 1,259 samples, the positive rate of HBoV was 4.53% (57/1,259), and among the 57 samples with positive HBoV, 75% (43/57) were positive in children with an age of 6-36 months. The positive rate of HBoV in children peaked in summer (from June to August), and there was a mixed infection with other viruses. Sequence analysis was performed for the PCR products from 36 positive samples, and the presence of HBoV was confirmed, with a higher homology to the known sequence of HBoV. CONCLUSIONS: In Tianjin, acute respiratory infection in some children may be associated with HBoV infection, which is commonly seen in infants with an age of 6-36 months. The peak of HBoV infection occurs in summer. The phylogenetic analysis shows a high homology to the known sequence of HBoV, with few gene sequence variations.
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Bocavirus/aislamiento & purificación , Infecciones del Sistema Respiratorio/virología , Bocavirus/clasificación , Niño Hospitalizado , Preescolar , Femenino , Humanos , Lactante , Masculino , Filogenia , Reacción en Cadena de la Polimerasa , Estaciones del AñoRESUMEN
OBJECTIVE To detect potential mutation in a Chinese family affected with beta-ureidopropinoase deficiency. METHODS Genomic DNA was extracted from peripheral blood samples. All exons and flanking intron regions of the UPB1 gene were amplified by PCR and detected by direct sequencing. RESULTS A homozygous mutation c.977G>A was identified in exon 9 of the UPB1 gene in the proband. Both parents of the proband had heterozygous change of the same site. CONCLUSION The c.977G>A mutation of the UPB1 gene is responsible for the pathogenesis of the disease in the infant.
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Anomalías Múltiples/genética , Amidohidrolasas/deficiencia , Encefalopatías/genética , Trastornos del Movimiento/genética , Mutación , Errores Innatos del Metabolismo de la Purina-Pirimidina/genética , Amidohidrolasas/genética , Exones , Humanos , Lactante , MasculinoRESUMEN
OBJECTIVE: To study the association of FCGR2A gene single nucleotide polymorphism (SNP) rs1801274 with Kawasaki disease (KD) susceptibility and the efficacy of intravenous immunoglobulin (IVIG) therapy in Han Chinese children. METHODS: Thirty-five KD children and 25 age-and gender-matched healthy children (control group) were enrolled in the study. Polymerase chain reaction (PCR) and gene sequence analysis were applied to detect SNP of FCGR2A gene rs1801274. These KD patients were classified into two subgroups based on the presence of coronary artery lesion (CAL) following IVIG therapy: CAL (n=13) and non-CAL (n=22). RESULTS: FCGR2A gene SNP rs1801274 was detected in all subjects, including three genotypes (AA, AG and GG). For FCGR2A gene SNP rs1801274, there were significant differences in the genotype and allele frequencies between the KD and control groups (P<0.05), and significant differences in the genotype and allele frequencies were also found between the CAL and non-CAL subgroups (P<0.05). A allele and AA genotype were linked to an increased risk of KD susceptibility (A allele: OR=3.39, 95%CI:1.53-7.50; AA genotype: (OR=4.93, 95%CI:1.61-15.1). Both AG (OR=5.43, 95%CI:1.06-27.8) and G allele (OR=4.88, 95%CI:1.44-16.5) were linked to an increased risk of CAL in KD children. CONCLUSIONS: Polymorphism of the FCGR2A gene SNP rs1801274 is one of the important factors probably influencing susceptibility to KD and efficacy of IVIG therapy on KD in Han Chinese children.
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Pueblo Asiatico/genética , Síndrome Mucocutáneo Linfonodular/genética , Polimorfismo de Nucleótido Simple , Receptores de IgG/genética , Niño , Preescolar , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Lactante , MasculinoRESUMEN
OBJECTIVE: To measure levels of cytokines including IL-1ß, IL-12, IL-18 and TNF-α in children with newly diagnosed type 1 diabetes and to analyze their correlation with clinical indices such as infection and onset time. METHODS: A total of 33 children with newly diagnosed type 1 diabetes were assigned to the case group, and 27 healthy children to the control group. The case group was further divided into increased white blood cell (WBC) and normal WBC subgroups according to peripheral WBC level. The serum levels of cytokines including IL-1ß, IL-12, IL-18 and TNF-α were measured by enzyme-linked immunosorbent assay. Blood pH, blood sugar, blood lactate, fructosamine, peripheral leukocytes and neutrophils and some other clinical indices were also measured. RESULTS: The level of IL-12 in the case group was higher than in the control group (P<0.001). In the case group, the level of IL-18 was negatively correlated with onset time (r=0.413, P=0.015), the neutrophil count was positively correlated with IL-1ß level (r=0.413, P=0.023) and the WBC count was positively correlated with IL-18 level (r=0.352, P=0.038). IL-1ß, IL-12 and IL-18 levels in the increased WBC subgroup were higher than in the normal WBC subgroup (P<0.05 for all comparisons). CONCLUSIONS: Cytokine secretion disorders of Th1 cells exist in children with type 1 diabetes. Infections may induce cytokine secretion and might contribute to the early onset of diabetes.
Asunto(s)
Citocinas/sangre , Diabetes Mellitus Tipo 1/inmunología , Células TH1/inmunología , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , MasculinoRESUMEN
OBJECTIVE: To investigate the infection rate and genotypes of Mycoplasma pneumoniae (MP) by examining bronchoalveolar lavage fluid from children with community acquired pneumonia (CAP). METHODS: Polymerase chain reaction (PCR) was used for detecting MP in bronchoalveolar lavage fluid from 220 children hospitalized with CAP, and the accuracy was confirmed by quantitative real-time PCR. Positive samples were digested with Haeâ ¡ and Hae â ¢ and compared with standard strain to analyze the genotypes of MP from positive samples. The accuracy of genotyping was confirmed by sequencing the amplified products of some randomly selected positive samples. RESULTS: The positive rate of MP in 220 samples was 55.0% (121/220). MP infection occurred mostly in preschool and school-age children (63.5%, 101/159), and the lowest positive rate was seen in children aged under 6 months (20%, 1/5). The positive rate showed no significant differences between sexes and between seasons. Sixty randomly selected MP-positive samples showed a genotype of P1 type 1 after restriction digestion, which was further confirmed by sequencing of 4 samples. CONCLUSIONS: MP is one of the main pathogens of pneumonia in children, and the MP infection rate is significantly correlated with age. The dominant genotype of MP in children is P1 type 1.
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Mycoplasma pneumoniae/genética , Neumonía por Mycoplasma/microbiología , Adolescente , Niño , Preescolar , Femenino , Genotipo , Hospitalización , Humanos , Lactante , Masculino , Mycoplasma pneumoniae/clasificación , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Estaciones del AñoRESUMEN
A prospective investigation was carried out among pediatric outpatients and inpatients with acute non-dysenteric diarrhea between August, 2008 and July, 2009 in Shanghai, Hangzhou, Chongqing, and Tianjin, China. One step real-time RT-PCR was used for detection of norovirus (NoV) genogroups I and II (GI, GII). The NoV genotypes were classified based on partial capsid sequences. Rotavirus (RV) was detected in parallel. Among 4,123 fecal samples from outpatients, 1,067 (25.9%) were NoV-positive, of which 1,051 (98.5%) belonged to GII and 1,309 (31.7%) were RV-positive. In the inpatient group (n = 317), 25.6% were NoV-positive and 41.6% were RV-positive. Four hundred and fifty-one out of 1,067 NoV-positive strains were sequenced and genotyped and 6 typed strains were GI (3 GI.3, 2 GI.5, 1 GI.4) and 445 typed strains were GII. GII strains clustered into nine genotypes including GII.4 2006b (69.2%), the only GII.4 variant identified in this study, followed by GII.3 (23.8%), GII.6 (3.6%), GII.12 (1.3%), GII.2 (0.9%), GII.13 (0.4%), GII.14 (0.2%), GII.7 (0.2%), and GII.16 (0.2%). A peak of NoV infections was observed during the cold season in Tianjin, while NoV activity was higher between late summer and autumn and lower during winter in Shanghai, Hangzhou, and Chongqing. NoV is a common causative agent of childhood diarrhea in China and the seasons of NoV-associated diarrhea varies between regions. The results show that NoV GII.4 2006b was the predominant strain circulating in China between 2008 and 2009.
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Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/virología , Gastroenteritis/epidemiología , Gastroenteritis/virología , Norovirus/clasificación , Norovirus/aislamiento & purificación , Adolescente , Niño , Preescolar , China/epidemiología , Análisis por Conglomerados , Femenino , Genotipo , Humanos , Lactante , Masculino , Epidemiología Molecular , Datos de Secuencia Molecular , Norovirus/genética , Prevalencia , Estudios Prospectivos , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADNRESUMEN
Viral diarrhea is a great threat to children's health in developing countries. We conducted a prospective surveillance study of acute diarrhea of young children at Tianjin Children's Hospital from April 2008 to April 2009. Viral infections were detected in 356 of the total 766 collected stool specimens (46.48%). Rotavirus infections were the most common (27.94%; predominant type G1), followed by adenovirus infections (17.62%; predominant type Ad41), norovirus infections (5.87%; predominant type GII-4/2006 b), and astrovirus infections (3.15%; only HAstV-1). Children younger than 1 year old were the most susceptible population to viral infections (87.9%). Diarrhea, vomiting, and fever were the most frequent clinical symptoms among the infected patients. The viral infections had no age, sex, or regional differences. Most infection rates were higher in the autumn, winter, and spring. This study supported that the rotavirus vaccine should be included in the Expanded Programme on Immunization in China.
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Diarrea/virología , Virus/aislamiento & purificación , Preescolar , China/epidemiología , Diarrea/epidemiología , Diarrea/etiología , Heces/virología , Femenino , Hospitalización , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Filogenia , Estudios Prospectivos , Estaciones del Año , Virus/clasificación , Virus/genéticaRESUMEN
The driver is one of the most important factors in the safety of the transportation system. The driver's perceptual characteristics are closely related to driving behavior, while electroencephalogram (EEG) as the gold standard for evaluating human perception is non-deceptive. It is essential to study driving characteristics by analyzing the driver's brain activity pattern, effectively acquiring driver perceptual characteristics, creating a direct connection between the driver's brain and external devices, and realizing information interchange. This paper first introduces the theories related to EEG, then reviews the applications of EEG in scenarios such as fatigue driving, distracted driving, and emotional driving. The limitations of existing research have been identified and the prospect of EEG application in future brain-computer interface automotive assisted driving systems have been proposed. This review provides guidance for researchers to use EEG to improve driving safety. It also offers valuable suggestions for future research.
RESUMEN
Train drivers' inattention, including fatigue and distraction, impairs their ability to drive and is the major risk factor for human-caused train accidents. Many experts have undertaken numerous studies on train driver exhaustion and distraction, but a systematic study is still missing. Through a systematic review, this work aims to outline the types, risk factors, consequences, and detection methods of train driver fatigue and distraction. The effects of central nervous fatigue and cognitive distraction in train drivers during driving are caused by rest and sleep schedules, workload, automation levels, and mobile phones. Furthermore, train drivers' fatigue and distraction can cause loss of concentration and slow reaction, resulting in dangerous driving behaviour such as speeding and SPAD. Researchers have combined subjective reporting, physiological parameters, and physical factors to construct detection algorithms with good results to detect train driver fatigue and distraction. This review offers recommendations for researchers looking into train driver fatigue and distraction. And it can also make valuable recommendations for future studies about railway traffic safety.