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1.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 38(12): 919-921, 2020 Dec 20.
Artículo en Zh | MEDLINE | ID: mdl-33406553

RESUMEN

Objective: To explore the feasibility of soft copy image of chest digital radiography (DR(SC)) in pneumoconiosis diagnosis by observing the reading effect of DR(SC) and comparing it with high kV film-screen chest radiography (FSR(HkV)) . To provide a basis for the establishment of a regional information network platform for pneumoconiosis diagnosis. Methods: A total of 119 miners who were exposed to silica dust and engaged in copper or lead-zinc mining were collected by the Third People's Hospital of Yunnan from October 2017 to August 2019. The pulmonary X-ray findings of DRSC and FSR(HkV) in each case were independently judged and diagnosed by three experienced diagnostic physicians, and the final decision was made according to the consensus of most doctors. The consistency of the two imaging methods was analyzed by observing the main small opacity shape, the overall density, the range of distribution, the aggregation of the small opacity and the big opacity, and the diagnosis stage. Results: there were 118 males and 1 female with an average age of 46.21 years. Average exposure time 7.38 years. The pulmonary X-ray findings of 113 cases with two imaging methods were mainly the round small opacity of p,q and r,but the reticular irregular opacity were not prominent, Only one case of FSR(HkV) judgment p shape and DR(SC) judgment q shape were observed, The coincidence rate was 99.12% (112/113) . huger opacity were observed in the other 6 cases. The coincidence rate was 95.51% (4/89) between pneumoconiosis-free and stageⅠ, and there was no significant difference between stageⅡand stage Ⅲ (30/30, P>0.05) . Conclusion: The x-ray findings of Silicosis with small round shadow in lung can be used by DR(SC) in diagnosis and staging.


Asunto(s)
Neumoconiosis , Silicosis , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumoconiosis/diagnóstico por imagen , Intensificación de Imagen Radiográfica , Radiografía , Radiografía Torácica , Silicosis/diagnóstico por imagen
2.
BJOG ; 125(9): 1077-1084, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29243299

RESUMEN

BACKGROUND: Evidence for the relationship between antidepressant use during pregnancy and the risk of attention-deficit/hyperactivity disorder (ADHD) in the children is conflicting. OBJECTIVE: To assess the association between fetal exposure to antidepressant drugs and the subsequent development of ADHD. SEARCH STRATEGY: A systematic literature search was conducted in PubMed, EMBASE, PsycINFO, and CINAHL databases to identify relevant cohort studies published from inception until October 2017. SELECTION CRITERIA: Cohort studies, identifying children with ADHD diagnosis and linking antidepressant use during pregnancy in their mothers. DATA COLLECTION: Two reviewers independently abstracted data and assessed study quality. MAIN RESULTS: The literature search identified six relevant cohort studies with association between antidepressant exposure during pregnancy and the risk of ADHD in children [hazard ratio (HR) 1.34; 95% confidence interval (CI) 1.14-1.57]. However, the association was not statistically significant when the reference group was mothers with psychiatric disorders not treated during pregnancy (HR 0.96; 95% CI 0.76-1.2; n = 2 studies). Moreover, preconception exposure to antidepressants was significantly associated with increased risk of ADHD (HR 1.82; 95% CI 1.54-2.15; n = 3 studies). CONCLUSIONS: The significant association between antidepressant exposure during pregnancy and ADHD in the children can be partially explained by confounding by indication. Given the low number of included studies, further studies with prospective designs that use validated measurements and controls for important confounders are needed to verify our findings. TWEETABLE ABSTRACT: Antidepressant use during pregnancy may be not associated with ADHD in the offspring.


Asunto(s)
Antidepresivos/efectos adversos , Trastorno por Déficit de Atención con Hiperactividad/inducido químicamente , Depresión/tratamiento farmacológico , Complicaciones del Embarazo/tratamiento farmacológico , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Niño , Estudios de Cohortes , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/psicología , Modelos de Riesgos Proporcionales
3.
Zhonghua Gan Zang Bing Za Zhi ; 25(4): 313-316, 2017 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-28494556

RESUMEN

Chronic hepatitis B (CHB) is a major infectious disease which threatens people's health around the world. Health-related quality of life (HRQoL) has become an important index for evaluating the treatment and prognosis of patients with CHB. Many studies abroad have shown that the HRQoL of patients with CHB is influenced by various factors. Disease severity, clinical symptoms, and low self-efficacy are important influencing factors for patients' quality of life. Anti-viral therapy, proper physical therapy, or psychological intervention can significantly improve the HRQoL of community CHB patients, and HRQoL is even significantly improved in patients undergoing liver transplantation one year ago. These studies provide valid evidence for antiviral therapy for hepatitis B patients and liver transplantation techniques from the psychological level. At present, there still lacks studies on HRQoL of CHB patients in China. This article summarizes the measurement tools for HRQoL widely used in recent years in China and foreign countries, reviews the research advances in HRQoL in community patients with CHB, and discusses the perspectives for future studies.


Asunto(s)
Antivirales , Hepatitis B Crónica/psicología , Hepatitis B Crónica/terapia , Trasplante de Hígado , Calidad de Vida , Antivirales/uso terapéutico , China/epidemiología , Femenino , Estado de Salud , Hepatitis B Crónica/etnología , Humanos , Masculino , Índice de Severidad de la Enfermedad
4.
Artículo en Zh | MEDLINE | ID: mdl-29081122

RESUMEN

Objective: To investigate the blood lead level of children living around lead-zinc mining areas, in order to analyze its distribution features of the population. Methods: In August 2016, three natural villiages around lead-zinc mines were selected randomly as survey sites, which were grouped A, B and C according to each distances from the center field, totally 1 379 children from the three villages were selected by cluster random sampling method as the investigation subjects, and their elbow peripheral vein blood samples were collected to determine the blood lead level by graphite furnace atomic absorption spectrometry. The distribution features of blood lead in different district, gender and age groups were compared and analyzed. Results: The median and quartile range of blood lead were 0.066 and 0.058 mg/L respectively. The blood lead levels of 341 children were esceeding 100 µg/L and that account for 24.73%. The median blood lead showed statistical significant differrnce among three groups (P<0.01) , and the medians from high to low were: 0.075 mg/L (A) , 0.065 mg/L (B) and 0.059 mg/L (C) respectively. The average blood lead of male was higher than that of female (P<0.01) . There was significant difference in blood lead levels among different aged groups (P<0.01) , and the high blood lead rate dicreased with the increase of age (P<0.01) . Results of multivariate logistic regression analysis showed that there was a high risk of excessive lead in the blood lead of boys aged 1-6 years from the center of the area. Conclusion: The blood lead level of children living around lead-zinc mining areas is relatively high. There are difference in district distribution, gender and age.


Asunto(s)
Exposición a Riesgos Ambientales , Plomo/sangre , Minería , Distribución por Edad , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Distribución por Sexo , Espectrofotometría Atómica , Encuestas y Cuestionarios , Zinc
5.
Physiol Res ; 71(5): 657-666, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-36047729

RESUMEN

Stem cells have emerged as promising therapeutic options for several human diseases, including pulmonary fibrosis (PF). In this study, we investigated the therapeutic effects of adipose tissue-derived mesenchymal stem cells (ADMSCs) in the bleomycin-induced PF model rats and the underlying mechanisms. The PF model rats were generated by intratracheal injections of 5 mg/kg bleomycin sulfate. The ADMSC group rats were generated by injecting 2×10(6) ADMSCs via the tail vein at 0, 12, and 24 h after bleomycin injection. The control, PF, and ADMSC group rats were sacrificed on day 21 after bleomycin injections and the changes in lung histology and the levels of pro-inflammatory cytokines, collagen I, and caveolin-1 (Cav-1), and the activity of the NF-kappaB signaling pathway in the lung tissues was assessed by hematoxylin-eosin staining, ELISA, and western blotting assays. The lung tissues of the PF model rats showed significant infiltration of neutrophils, tissue destruction, and collagen deposition, but these effects were abrogated by the ADMSCs. The levels of pro-inflammatory cytokines such as IL-6, IL-1beta, and TGF-beta1 were elevated in the lung tissues and the bronchoalveolar lavage fluid (BALF) of the bleomycin-induced PF model rats, but these effects were reversed by the ADMSCs. The lung tissues of the PF model rats showed significant downregulation of Cav-1 and significantly higher activation of the pro-inflammatory NF-kappaB pathway. However, administration of the ADMSCs restored the expression levels of Cav-1 and suppressed the NF-kappaB signaling pathway in the lungs of the bleomycin-induced PF model rats. In conclusion, this study demonstrated that the ADMSCs protected against bleomycin-induced PF in the rat model by modulating the Cav-1/NF-kappaB axis.


Asunto(s)
Células Madre Mesenquimatosas , Neumonía , Fibrosis Pulmonar , Animales , Ratas , Bleomicina/toxicidad , Caveolina 1/metabolismo , Caveolina 1/farmacología , Caveolina 1/uso terapéutico , Colágeno/metabolismo , Citocinas/metabolismo , Pulmón , Células Madre Mesenquimatosas/metabolismo , FN-kappa B/metabolismo , Neumonía/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/terapia , Fibrosis Pulmonar/metabolismo , Ratas Sprague-Dawley , Transducción de Señal
6.
Artículo en Zh | MEDLINE | ID: mdl-34666446

RESUMEN

Objective: To analyze the clinical manifestations of a patient with branchiootic syndrome(BOS) and her families and to carry out genetic testing in order to specify the biological pathogenesis. Methods: Clinical data of the patient and her families were collected. Genomic DNA in the peripheral blood of the proband and her family members was extracted. All exons of 406 deafness-related susceptible genes as well as their flanking regions were sequenced by high-throughput sequencing, and the mutation sites of the proband and her parents were validated by Sanger sequencing. Results: There were nine members in three generations, of whom four presented with hearing loss, preauricular fistula and branchial fistula which met the diagnostic criteria of BOS. Proband and her mother presented with auricle malformation and inner ear malformation. And no one had abnormalities in the kidneys of all the patients. Pedigree analysis revealed that the mode of inheritance in the family was consistent with the autosomal dominant pattern. Mutational analysis showed that all the affected patients detected a heterozygous frameshift variation c.1255delT in the EYA1 gene, which had not been reported. Genotype and phenotype were co-isolated in this family. Such a frameshift variation produced a premature termination codon, thereby causing premature termination of translation (p.C419VFS*12). ACMG identified that the mutation was pathogenic. This mutation was novel and not detected in controls. A heterozygous missense variation mutation c.403G>A(p.G135S) in EYA1 gene was also detected in three members of this family. ACMG identified that the mutation clinical significance was uncertain. However, two of whom were normal, which seemed the disease was not caused by this mutation in this family. Conclusions: A novel frameshift mutation in EYA1(c.1255delT) is the main molecular etiology of BOS in the Chinese family. This study expands the mutational spectrum of EYA1 gene. The clinical manifestations are heterogeneous among patients in this family. The diagnosis of BOS should combine gene tests with clinical phenotypes analysis.


Asunto(s)
Síndrome Branquio Oto Renal , Síndrome Branquio Oto Renal/genética , Análisis Mutacional de ADN , Femenino , Pruebas Genéticas , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Mutación , Proteínas Nucleares , Linaje , Proteínas Tirosina Fosfatasas/genética
7.
Artículo en Zh | MEDLINE | ID: mdl-33472302

RESUMEN

Objective: To screen and analyze the mutations of MITF gene in two children of type Ⅱ Waardenburg syndrome (WS2) from different families in Yunnan,China,and to explore the possible molecular pathogenesis. Methods: With informed consent, medical history collection, physical examinations, audiological evaluation, and high resolution computer tomography (HRCT) scan of temporal bone were performed on the two WS2 probands and their family members. Genomic DNA was extracted from peripheral blood of all individuals. The coding regions including all exons, part of introns and promoters of MITF, PAX3, SOX10, SNAI2, END3, ENDRB, and KITLG genes were sequenced by high-throughput sequencing. According to the results of high-throughput sequencing, pathogenic mutations detected in the probands and their parents were verified by Sanger sequencing. Results: The proband 1 carried c.641_643delGAA mutation in the 7th exon of MITF gene, which was a frame-shift mutation resulting in an amino acid change of p.214delR. It was a de novo mutation as the parents of proband 1 showed no variation on this site. The proband 2 carried heterozygous loss of the large fragment ranging from exon 1 to exon 9 of MITF gene, which defected the function of MITF protein. Conclusion: Genetic examinations provide important evidence for diagnosis of Waardenburg syndrome. Heterozygous mutation c.641_643delGAA and heterozygous loss of the large fragment ranging from exon 1 to exon 9 of MITF gene might be the molecular pathogenesis of the two WS2 probands in this study.


Asunto(s)
Síndrome de Waardenburg , Pueblo Asiatico/genética , Niño , China , Humanos , Mutación , Linaje , Factores de Transcripción SOXE/genética , Síndrome de Waardenburg/genética
8.
Rev Sci Instrum ; 89(10): 10H105, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30399888

RESUMEN

The capabilities of the joint-Texas experimental tokamak correlation electron cyclotron emission (CECE) diagnostic have recently been extended with an upgrade. Four new yttrium iron garnet (YIG) filters from 4 GHz to 18 GHz with a bandwidth of 90 ∼ 230 MHz are added to the previous 4 channels. Optical optimization of the transmission line has improved the poloidal resolution, which allows k θ < 3.08 cm-1. The improvement of video amplifiers allows the frequency and amplitude gain to be adjusted discretely from 200 kHz to 1 MHz and from 200 to 1000, respectively, for different situations. A controller is designed to remotely adjust the center frequency of the YIG filters. Based on the CECE, the distribution and the effect of magnetohydrodynamic instabilities on electron temperature fluctuations have been observed. The experiment results show good performance of the upgraded CECE diagnostic.

9.
Artículo en Zh | MEDLINE | ID: mdl-29798205

RESUMEN

Objective:To investigate the surgical treatment of cholesteatoma of the middle ear. Method:A retrospective analysis of patients from June 2013 to July 2016 diagnosed as cholesteatoma. 137 ears were divided into A group (retaining part of the external auditory canal posterior wall with epitympanoplasty in soft wall reconstruction for 75 ears) and B group (canal wall down mastoidotympanoplasty for 62 ears). the extent and damage of cholesteatoma were observed, comparing the time of dry ear and epithelial postoperative, the incidence of complications such as dizziness and hearing changes. Result:compared with B group, the postoperative dry ear time, epithelial time and hearing improvement in the A group were obviously improved, and the incidence of vertigo after operation was decreased, and the anatomical and physiological functions of the external auditory canal were protected. Conclusiont:The technique of retaining part of the external auditory canal posterior wall with epitympanoplasty in soft wall reconstruction is conductive to the removal of lesions and normal anatomical and physiological protection to external auditory canal, can prevent the forming of the abstraction pocket effectively and the recurrence of cholesteatoma, has clinical and practical value.


Asunto(s)
Colesteatoma del Oído Medio/cirugía , Timpanoplastia , Conducto Auditivo Externo , Oído Medio , Estudios de Seguimiento , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
10.
Rev Sci Instrum ; 87(11): 11E112, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910414

RESUMEN

To meet experimental requirements, the J-TEXT electron cyclotron emission (ECE) diagnostic is being upgraded. The front end antenna and transmission line have been modified and a new 8-channel W-band detecting unit has been developed. The improved ECE system will extend the frequency range from 94.5-124.5 GHz to 80.5-124.5 GHz. This will enable the system to cover the most plasma in the radius direction for BT = 1.8-2.2 T, and it even can cover almost the whole plasma range ρ = - 0.8-0.9 (minus means the high field side) at BT = 1.8 T. A new auxiliary channel bank with 8 narrow band, tunable yttrium iron garnet filters is planned to add to the ECE system. Due to observations along a major radius, perpendicular to BT, and relatively low electron temperature, Doppler and relativistic broadening are minimal and thus high spatial resolution measurements can be made at variable locations with these tunable channels.

11.
Artículo en Zh | MEDLINE | ID: mdl-29771067

RESUMEN

Objective:To discuss the minimally invasive surgical techniques and the effect of cochlear implantation with round window pathways in young children(≤3 years).Method:One hundred and sixty patients with bilateral profound sensorineural hearin loss received MED-EL cochlear implantation,including 144 cases of normal middle and inner ear,4 cases of Mondini deformity,12 cases of large vestibular aqueduct syndrome.Result:Of 160 patients underwent CIs,148 patients were performed with round window pathways,the rate was 92.5%. Iit's difficult to exposure round window in 12 patients,performing from promontory.All electrodes of 158 cases with unilateral CI and 2 cases with bilateral CI were implanted successfully,in which the CI went normally and electrode array were protected well.All implant devices had worked normally and all patients had performed well during an average follow-up period of 8 month-3 years.Post-operatively complications of cerebrospinal fluid leakage,facial nerve injury haven't been found.Conclusion:Cochlear implantation could be performed in patients wit with round window pathways,and it is a safe and effective way in young children.


Asunto(s)
Implantación Coclear/métodos , Implantes Cocleares , Ventana Redonda/cirugía , Niño , Preescolar , Oído Interno/cirugía , Femenino , Pérdida Auditiva Sensorineural/cirugía , Humanos , Lactante , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos , Complicaciones Posoperatorias , Síndrome , Acueducto Vestibular
12.
Rev Sci Instrum ; 87(11): 11E106, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910430

RESUMEN

A new 2D Electron Cyclotron Emission Imaging (ECEI) diagnostic is being developed for the J-TEXT tokamak. It will provide the 2D electron temperature information with high spatial, temporal, and temperature resolution. The new ECEI instrument is being designed to support fundamental physics investigations on J-TEXT including MHD, disruption prediction, and energy transport. The diagnostic contains two dual dipole antenna arrays corresponding to F band (90-140 GHz) and W band (75-110 GHz), respectively, and comprises a total of 256 channels. The system can observe the same magnetic surface at both the high field side and low field side simultaneously. An advanced optical system has been designed which permits the two arrays to focus on a wide continuous region or two radially separate regions with high imaging spatial resolution. It also incorporates excellent field curvature correction with field curvature adjustment lenses. An overview of the diagnostic and the technical progress including the new remote control technique are presented.

13.
Braz J Med Biol Res ; 48(12): 1145-50, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26517336

RESUMEN

This study investigated the value of computed tomography (CT) in the diagnosis and treatment of hepatic veno-occlusive disease (HVOD) caused by Sedum aizoon (SA). The clinical manifestations, treatment results, imaging findings, and histological findings of the liver were analyzed in 39 patients with HVOD caused by SA. Hepatomegaly, liver dysfunction, abdominal effusion, and geographic density changes on liver CT scans were found in all 39 patients. The pathological findings of histological liver examination included swelling and point-like necrosis of liver cells, significant expansion and congestion of the sinuses, endothelial swelling, and wall thickening with incomplete lumen occlusion of small liver vessels. CT geographic density changes were confirmed by histological examination of the liver in 18 patients. Sixteen patients with small amounts of ascites that started within 4 weeks of treatment recovered completely or significantly improved after symptomatic and supportive treatment. However, only 43.75% of the patients with larger amounts of ascites improved following symptomatic and supportive treatment. In conclusion, liver CT examination is a valuable, safe, and noninvasive tool for the diagnosis of HVOD caused by SA. In selected cases, liver CT examination may replace liver biopsy and histological analysis.


Asunto(s)
Medicamentos Herbarios Chinos/envenenamiento , Enfermedad Veno-Oclusiva Hepática/diagnóstico por imagen , Circulación Hepática/efectos de los fármacos , Sedum/envenenamiento , Adulto , Anciano , Ascitis/etiología , Biopsia , China , Femenino , Enfermedad Veno-Oclusiva Hepática/etiología , Enfermedad Veno-Oclusiva Hepática/patología , Humanos , Masculino , Persona de Mediana Edad , Necrosis , Estudios Retrospectivos , Sedum/clasificación , Tomografía Computarizada por Rayos X
14.
Protein Sci ; 7(11): 2345-53, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9828000

RESUMEN

We have devised a procedure using monovalent phage display to select for stable mutants in the pro-domain of the serine protease, subtilisin BPN'. In complex with subtilisin, the pro-domain assumes a compact structure with a four-stranded antiparallel beta-sheet and two three-turn alpha-helices. When isolated, however, the pro-domain is 97% unfolded. These experiments use combinatorial mutagenesis to select for stabilizing amino acid combinations at a particular structural locus and determine how many combinations are close to the maximum protein stability. The selection for stability is based on the fact that the independent stability of the pro-domain is very low and that binding to subtilisin is thermodynamically linked to folding. Two libraries of mutant pro-domains were constructed and analyzed to determine how many combinations of amino acids at a particular structural locus result in the maximum stability. A library comprises all combinations of four amino acids at a structural locus. Previous studies using combinatorial genetics have shown that many different combinations of amino acids can be accommodated in a selected locus without destroying function. The present results indicate that the number of sequence combinations at a structural locus, which are close to the maximum stability, is small. The most striking example is a selection at an interior locus of the pro-domain. After two rounds of phagemid selection, one amino acid combination is found in 40% of sequenced mutants. The most frequently selected mutant has a deltaG(unfolding) = 4 kcal/mol at 25 degrees C, an increase of 6 kcal/mol relative to the naturally occurring sequence. Some implications of these results on the amount of sequence information needed to specify a unique tertiary fold are discussed. Apart from possible implications on the folding code, the phage display selection described here should be useful in optimizing the stability of other proteins, which can be displayed on the phage surface.


Asunto(s)
Aminoácidos/química , Bacteriófagos/genética , Subtilisinas/química , Subtilisinas/genética , Secuencia de Aminoácidos , Bacteriófagos/enzimología , Secuencia de Consenso , Estabilidad de Enzimas , Biblioteca de Genes , Cinética , Modelos Moleculares , Estructura Molecular , Mutagénesis Sitio-Dirigida , Pliegue de Proteína , Estructura Secundaria de Proteína , Relación Estructura-Actividad , Temperatura , Termodinámica
15.
Acta Biochim Pol ; 48(2): 313-21, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11732603

RESUMEN

Translation is the process by which ribosomes direct protein synthesis using the genetic information contained in messenger RNA (mRNA). Transfer RNAs (tRNAs) are charged with an amino acid and brought to the ribosome, where they are paired with the corresponding trinucleotide codon in mRNA. The amino acid is attached to the nascent polypeptide and the ribosome moves on to the next codon. Thus, the sequential pairing of codons in mRNA with tRNA anticodons determines the order of amino acids in a protein. It is therefore imperative for accurate translation that tRNAs are only coupled to amino acids corresponding to the RNA anticodon. This is mostly, but not exclusively, achieved by the direct attachment of the appropriate amino acid to the 3'-end of the corresponding tRNA by the aminoacyl-tRNA synthetases. To ensure the accurate translation of genetic information, the aminoacyl-tRNA synthetases must display an extremely high level of substrate specificity. Despite this highly conserved function, recent studies arising from the analysis of whole genomes have shown a significant degree of evolutionary diversity in aminoacyl-tRNA synthesis. For example, non-canonical routes have been identified for the synthesis of Asn-tRNA, Cys-tRNA, Gln-tRNA and Lys-tRNA. Characterization of non-canonical aminoacyl-tRNA synthesis has revealed an unexpected level of evolutionary divergence and has also provided new insights into the possible precursors of contemporary aminoacyl-tRNA synthetases.


Asunto(s)
Evolución Molecular , Genómica , Aminoacil-ARN de Transferencia/biosíntesis , Aminoacil-ARN de Transferencia/genética , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Filogenia , Biosíntesis de Proteínas , ARN Mensajero/genética
16.
Steroids ; 64(6): 385-95, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10433175

RESUMEN

Asymmetric dihydroxylation of (20(22)E)-cholesta-5,20(22)-dien-3beta-ol acetate (2a), prepared from pregnenolone, gave a 1:1 mixture (67% yield) of (20R,22R)-cholest-5-ene-3beta,20,22-triol 3-acetate (3a) and its 20S,22S isomer 3b. Highly purified 3a and 3b were obtained by semipreparative silver ion high performance liquid chromatography. Saponification of 3a and 3b gave (20R,22R)-cholest-5-ene-3beta,20,22-triol (4a) and its 20S,22S isomer 4b. This simple approach provided the natural isomer 4a more efficiently than previously described chemical or enzymatic syntheses. Full 1H and 13C nuclear magnetic resonance data were presented for triols 4a and 4b and their synthetic precursors. Side-chain conformations of 2a, its 20(22)Z isomer, 4a, and 4b were studied by molecular mechanics and nuclear Overhauser effect difference spectroscopy.


Asunto(s)
Hidroxicolesteroles/síntesis química , Pregnenolona/biosíntesis , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas de Unión al ADN , Hidroxicolesteroles/química , Hidroxicolesteroles/metabolismo , Receptores X del Hígado , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular , Receptores Nucleares Huérfanos
17.
Steroids ; 65(1): 29-39, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10624834

RESUMEN

Five unsaturated sterols relevant to the Smith-Lemli-Opitz syndrome have been prepared in high radiochemical purity with a tritium label at the 3alpha position. Swern oxidation of cholesta-5,8-dien-3beta-ol and other unlabeled C27 sterols afforded the corresponding 3-ketosteroids, and reduction with tritiated NaBH4 gave the desired 3alpha-3H sterols, with double bonds at the delta(5,8), delta(5,8(14)), delta(6,8), delta(6,8(14)), and delta8 positions. High radiochemical purity of the tritiated sterols was demonstrated by normal phase, reversed phase, and silver-ion (Ag+) high-performance liquid chromatography (HPLC). In the course of this work, we developed a medium-pressure variant of Ag+-HPLC for purifying radiolabeled samples, documented significant isotopic fractionation of the 3alpha-tritiated sterols and their acetates on Ag+-HPLC, and discovered unexpected effects of a delta(8(14)) bond on the conformation of 3-keto-delta5-steroids. The synthetic and analytical methodologies described herein should provide a sound basis for investigating the origin and metabolism of sterols involved in the Smith-Lemli-Opitz syndrome and in late stages of cholesterol biosynthesis.


Asunto(s)
Colestadienoles/síntesis química , Síndrome de Smith-Lemli-Opitz/metabolismo , Esteroles/síntesis química , Colestadienoles/metabolismo , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Radioquímica , Espectrofotometría Ultravioleta , Esteroles/metabolismo , Tritio
18.
Zhonghua Nei Ke Za Zhi ; 38(11): 733-6, 1999 Nov.
Artículo en Zh | MEDLINE | ID: mdl-11798711

RESUMEN

OBJECTIVE: To evaluate the significance of hepatitis E virus antibody (anti-HEV) IgG and IgM for the diagnosis of acute hepatitis E. METHODS: Acute phase sera from a total of 143 patients with sporadic hepatitis E in 7 cities of China were determined for anti-HEV IgM and IgG by using an enzyme-linked immunosorbent assay (EIA). 359 serial sera of 56 patients with hepatitis E and 68 serial sera of 4 rhesus macaques experimentally infected with hepatitis E virus (HEV) were also detected for anti-HEV IgG and IgM. RESULTS: In the 143 patients the positive rate of anti-HEV IgG was 100.0%, which was significantly higher than that of anti-HEV IgM (73.4%, 105/143). 97.2% of anti-HEV IgG positive patients had a titer over 1:40. The positive rate of anti-HEV IgM increased with the titer of anti-HEV IgG in sera. It was 0% (0/4), 44.4% (8/18) and 80.2% (97/121), respectively in patients with the anti-HEV IgG titer of 1:20, 1:40 and >or=1:80 (P < 0.001). All the anti-HEV IgM positive patients were also anti-HEV IgG positive. No patients were found to be anti-HEV IgM positive alone. Anti-HEV IgG was detected as early as 2 days after onset of the disease, with a cumulative positive seroconversion rate of 100% by 1 month. The negative seroconversion rate of anti-HEV IgG increased with course of the disease and 43.3% of the patients lost their anti-HEV IgG by 6 months after illness. Though anti-HEV IgM also seroconverted at the same time as anti-HEV IgG, its cumulative positive seroconversion rate was only 71.4% and declined rapidly. Up to 37.5% of anti-HEV IgM positive patients became negative by 1 month after onset. Similar antibody responses were observed in 4 rhesus macaques experimentally infected with HEV. CONCLUSION: It is suggested that as a result of the poor sensitivity of currently available anti-HEV IgM EIA kits, anti-HEV IgG will be a more reliable marker for the diagnosis of acute hepatitis E as compared with anti-HEV IgM.


Asunto(s)
Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/inmunología , Hepatitis E/diagnóstico , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Enfermedad Aguda , Animales , Ensayo de Inmunoadsorción Enzimática , Humanos , Macaca mulatta , Sensibilidad y Especificidad
19.
Zhonghua Yi Xue Za Zhi ; 78(7): 498-500, 1998 Jul.
Artículo en Zh | MEDLINE | ID: mdl-10923456

RESUMEN

OBJECTIVE: To study the dynamics of anti-HEV ORF2, ORF3, IgM and IgG in serial sera of patients with hepatitis E. METHODS: Anti-HEV was detected in serial sera of 52 patients, by an enzyme-linked immunosorbent assay (EIA) based on two synthetic peptides separated or combined from open reading frame (ORF) 2 and 3 of HEV genome. RESULTS: Both anti-ORF2 and anti-ORF3 in serum were at the highest levels in early acute phase of the disease, and declined gradually with the course, especially anti-ORF3. The sensitivity of the EIA using both ORF2 and ORF3 peptides was higher than that of either alone. The positive rates of anti-HEV IgM and anti-HEV IgG were separately 71.1% (32/45) and 97.8% (44/45) within 15 days after onset, then decreased more dramatically in IgM than in IgG with the course. CONCLUSION: Both ORF2 and ORF3 proteins should be used for the development of anti-HEV EIA kit. It seems to be more specific in anti-HEV IgM and more sensitive in anti-HEV IgG as a diagnostic marker of hepatitis E.


Asunto(s)
Anticuerpos Antihepatitis/sangre , Virus de la Hepatitis E/genética , Hepatitis E/inmunología , Hepatitis E/virología , Proteínas Virales/inmunología , Adolescente , Adulto , Anciano , Ensayo de Inmunoadsorción Enzimática , Femenino , Anticuerpos Antihepatitis/genética , Virus de la Hepatitis E/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad
20.
Zhonghua Fu Chan Ke Za Zhi ; 33(11): 649-51, 1998 Nov.
Artículo en Zh | MEDLINE | ID: mdl-10806710

RESUMEN

OBJECTIVE: To analyze cardiotocograph by computer, the tracings recorded in paper form must first be converted into their digital equivalent. We developed a method by which this process may be performed. METHODS: Paper recordings were first scanned using a conventional flat bed scanner to obtain a digital image. Each image was firstly corrected for rotational misalignment error during scanning and, sceondly the grid was removed by performing logistic contrast enhancement to leave the discrete fetal heart rate and tocographic tracings. The method was validated by comparing differences between the fetal heart rate obtained from the paper record with that directly obtained from the fetal monitor. RESULTS: Forty recordings were analyzed. The mean difference per recording between the actual and derived values ranged from -0.26(-)-1.26 beats per minute. The 95% confidence interval for the pooled differences between the derived and actual fetal heart rate values was--7-5 beats per minute. CONCLUSION: By using the techniques described in this paper, it is now possible to convert the large number of paper records available so that they can be analyzed by computerized cardiotocograph interpreters.


Asunto(s)
Cardiotocografía , Frecuencia Cardíaca Fetal , Procesamiento Automatizado de Datos , Femenino , Humanos , Embarazo
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