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1.
Public Health ; 210: 34-40, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35870319

RESUMEN

OBJECTIVES: Contact tracing for COVID-19 relies heavily on the cooperation of individuals with authorities to provide information of contact persons. However, few studies have clarified willingness to cooperate and motivation to provide information for contact tracing. This study sought to describe willingness to cooperate and motivation to report contact persons for COVID-19 contact tracing among citizens in Japan, and to assess any associated sociodemographic factors. STUDY DESIGN: Cross-sectional study. METHODS: This was an online-based survey using quota sampling. Participants were asked about their willingness to cooperate in reporting contacts for COVID-19 contact tracing if they tested positive. Participants also responded to questions regarding their reasons for cooperating or not cooperating and provided sociodemographic data. Multiple logistic regression analysis was performed to clarify associations between sociodemographic factors and willingness to cooperate. RESULTS: This study included 2844 participants. The proportion of participants who were not willing to cooperate in reporting contacts was 27.6%, with their main reasons being concerns about causing trouble for the other person and being criticised for revealing their names. Willingness to cooperate was lower among men, young adults and those with an educational level less than a university degree. CONCLUSIONS: To improve the effectiveness of contact tracing, educational campaigns, such as reducing the fear and stigma associated with COVID-19, may be important. Furthermore, it is essential to understand that individuals may have contacts whom they do not wish to disclose to others and to be considerate when handling such situations.


Asunto(s)
COVID-19 , Trazado de Contacto , COVID-19/epidemiología , Estudios Transversales , Humanos , Japón/epidemiología , Masculino , Encuestas y Cuestionarios , Adulto Joven
3.
Ultrasound Obstet Gynecol ; 54(2): 199-206, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30381845

RESUMEN

OBJECTIVE: To evaluate Sylvian fissure development by assessing Sylvian fissure angles in fetuses with malformation of cortical development (MCD). METHODS: This was a retrospective study of 22 fetuses with MCD. Cases with a stored three-dimensional (3D) brain volume acquired at 18 + 0 to 30 + 6 weeks of gestation at an ultrasound-based research clinic between January 2010 and December 2017 were identified through a database. Of the 22 fetuses, seven had an extracranial abnormality, such as cardiac, renal, gastrointestinal and/or digital anomalies, and five had a minor abnormality such as micrognathia, low-set ears and/or single umbilical artery. To confirm the final clinical diagnosis of brain abnormality, postmortem histological findings or prenatal or postnatal magnetic resonance images were used. For measurement of Sylvian fissure angle, an anterior coronal plane of the fetal brain on transvaginal 3D volume multiplanar imaging was visualized as a single image from the three orthogonal views. The right and left Sylvian fissure angles were measured between a horizontal reference line (0°) and a line drawn along the upper side of the respective Sylvian fissure. The Sylvian fissure angle on both sides was plotted on the graphs of the reference ranges for gestational age in weeks. RESULTS: In 21 (95.5%; 95% CI, 86.8-100.0%) of 22 fetuses with MCD, the Sylvian fissure angle on one or both sides was larger than the 90th percentile of the normal reference. There was one case with apparent focal MCD in the parietal lobe, but the Sylvian fissure angles were normal. A case with apparent unilateral cortical dysplasia and one with apparent unilateral schizencephaly had conspicuous discrepancies between the left and right Sylvian fissure angles. Abnormal genetic test results were obtained in six cases, including four cases with a mutation in a single gene. CONCLUSIONS: This study has shown that the Sylvian fissures, as defined by the Sylvian fissure angle, have delayed development in most MCD cases prior to the diagnosis of the condition. The Sylvian fissure angle may potentially be a strong indicator for the subsequent development of cortical malformation, before the time point at which the gyri and sulci become obvious on the fetal brain surface. Further research is required to validate these findings. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Corteza Cerebral/anomalías , Corteza Cerebral/diagnóstico por imagen , Anomalías Congénitas/diagnóstico por imagen , Malformaciones del Desarrollo Cortical/diagnóstico por imagen , Autopsia , Encéfalo/anatomía & histología , Encéfalo/diagnóstico por imagen , Corteza Cerebral/embriología , Anomalías Congénitas/genética , Anomalías Congénitas/patología , Femenino , Desarrollo Fetal , Feto , Edad Gestacional , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética/métodos , Malformaciones del Desarrollo Cortical/genética , Malformaciones del Desarrollo Cortical/patología , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Valores de Referencia , Estudios Retrospectivos , Ultrasonografía Doppler Transcraneal/métodos , Ultrasonografía Prenatal/métodos
4.
Ultrasound Obstet Gynecol ; 54(2): 190-198, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30381851

RESUMEN

OBJECTIVE: To (1) evaluate the normal development of the Sylvian fissures in the anterior coronal view of the fetal brain at 18-30 weeks' gestation by transvaginal three-dimensional (3D) ultrasound, (2) develop reference ranges of measurements of the right and left Sylvian fissure angles during normal pregnancy at 18-30 weeks' gestation, and (3) examine intra- and interobserver repeatability of measurements of the right and left Sylvian fissure angles. METHODS: This was a prospective cross-sectional study of 422 women with a singleton pregnancy attending an ultrasound-based research clinic between March and December 2017. The entry criteria for the study were appropriately grown live fetus with no suspected structural and/or chromosomal defects between 18 + 0 and 30 + 6 weeks' gestation. Normal development of the Sylvian fissures was assessed in the anterior coronal plane of the fetal brain using transvaginal 3D volume multiplanar imaging. The coronal view was visualized as a single image from the three orthogonal views. Subsequently, the right and left Sylvian fissure angles were measured between a horizontal reference line (0°) and a line drawn along the upper side of the respective Sylvian fissure. Intra- and interobserver repeatability of the Sylvian fissure angle measurements was assessed by Bland-Altman plots. Reference equations were constructed for right and left Sylvian fissure angles for gestational age (GA) and head circumference (HC) using the Generalized Additive Models for Location Scale and Shape package. RESULTS: In the anterior coronal view of the fetal brain, an inward rotation of the upper portion of the Sylvian fissures was observed during the second and third trimesters of pregnancy. There was a significant negative polynomial association between the Sylvian fissure angles and GA and HC. Both Sylvian fissure angles crossed the reference line (zero), going from positive to negative, at around 25 weeks' gestation or at HC of 22 cm. Z-score difference between the smoothed percentiles of the right and left Sylvian fissure angles indicated that median, 10th and 90th smoothed percentiles were closest and almost the same for the GA-based references between 18 and 28 weeks and for the HC-based references between 14 and 24 cm. The intraclass correlation coefficient of the right and left Sylvian fissure angle measurements between the two sonographers was excellent at 0.993 (95% CI, 0.988-0.996) and 0.991 (95% CI, 0.985-0.995), respectively. On Bland-Altman analysis, the mean difference between the two sonographers in right Sylvian fissure angle measurement was 0.4° (95% CI, -10.2 to 10.1°) and in left Sylvian fissure angle it was 1.0° (95% CI, -9.6 to 11.6°). CONCLUSIONS: Assessment of the Sylvian fissure angles is highly reproducible. Sylvian fissure angle reference charts can serve as a screening tool for malformations of cortical development, guiding subsequent follow-up and referral for fetal brain magnetic resonance imaging and/or assessment by an expert neurosonologist. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Corteza Cerebral/anatomía & histología , Corteza Cerebral/diagnóstico por imagen , Imagenología Tridimensional/instrumentación , Adulto , Corteza Cerebral/embriología , Estudios Transversales , Femenino , Desarrollo Fetal/fisiología , Edad Gestacional , Humanos , Variaciones Dependientes del Observador , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Valores de Referencia , Ultrasonografía , Ultrasonografía Prenatal/métodos
5.
Osteoporos Int ; 27(12): 3495-3502, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27341809

RESUMEN

We conducted a prospective comparative study of the effect of teriparatide therapy for preventing vertebral-failure-type PJK after reconstructive surgery for adult spinal deformity. Prophylactic teriparatide improved the volumetric bone mineral density and fine bone structure of the vertebra above the upper-instrumented vertebra and reduced the incidence of vertebral-failure-type PJK. INTRODUCTION: Proximal junctional kyphosis (PJK) is a complication after corrective surgery for spinal deformity. This study sought to determine whether teriparatide (TP) is an effective prophylactic against PJK type 2 (vertebral fracture) in surgically treated patients with adult spinal deformity (ASD). METHODS: Forty-three patients who started TP therapy immediately after surgery and 33 patients who did not receive TP were enrolled in this prospective case series. These patients were female, over 50, surgically treated for ASD, and followed for at least 2 years. Preoperative and postoperative standing whole-spine X-rays and dual-energy X-ray absorptiometry scans, and multidetector CT images obtained before and 6 months after surgery were used to analyze the bone strength in the vertebra above the upper-instrumented vertebra (UIV+1). RESULTS: Mean age was 67.9 years. After 6 months of treatment, mean hip-bone mineral density (BMD) increased from 0.721 to 0.771 g/cm2 in the TP group and decreased from 0.759 to 0.729 g/cm2 in the control group. This percent BMD change between groups was significant (p < 0.05). The volumetric BMD (326 to 366 mg/cm3) and bone mineral content (BMC) (553 to 622 mg) at UIV+1 were also significantly increased in TP group. The bone volume/tissue volume ratio increased from 46 to 54 % in the TP group, and the trabecular bone thickness and number increased by 14 and 5 %, respectively. At the 2-year follow-up, the PJK type 2 incidence was significantly lower in the TP group (4.6 %) than in the control group (15.2 %; p = .02). CONCLUSIONS: Prophylactic TP treatment improved the volumetric BMD and fine bone structure at UIV+1 and reduced the PJK-type 2 incidence.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Columna Vertebral/efectos de los fármacos , Teriparatido/uso terapéutico , Anciano , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Columna Vertebral/anomalías , Columna Vertebral/cirugía , Resultado del Tratamiento
6.
Spinal Cord ; 54(9): 656-61, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26620877

RESUMEN

STUDY DESIGN: A cross-sectional study. OBJECTIVES: Neuropathic pain (NP) after spinal cord injury (SCI) tends to be hard to treat, and its heterogeneous properties make it difficult to identify and characterize. This study was conducted to assess the characteristics of SCI-related NP in detail. SETTING: A single hospital for SCI rehabilitation. METHODS: This study included 72 patients who were seen at our hospital in 2012 and 2013 and who had sustained SCI at least 3 months before enrollment. The patients completed the Neuropathic Pain Symptom Inventory (NPSI) and the Short Form (SF)-36 Health Inventory. The NPSI score was analyzed for correlations with clinical presentations of SCI and SF-36 subitems. RESULTS: Paresthesia/dysesthesia was the most common subtype of NP after SCI. With regard to location, below-level superficial NP was significantly more intense than at-level pain. Patients who underwent surgery showed significantly less evoked pain compared with patients with non-surgery. Patients reported significantly more severe pain if >1 year had elapsed after the SCI. Patients with an American Spinal Injury Association Impairment Scale grade of B for completeness of injury reported more intense NP than those with other grades. Among the SF-36 subitems, NP correlated significantly with bodily pain, general health and mental health. CONCLUSION: NP in SCI patients was significantly associated with the location of pain, the time period since the injury, surgery and quality-of-life factors. A more detailed understanding of the characteristics of NP may contribute to better strategies for relieving the pain associated with SCI.


Asunto(s)
Neuralgia/etiología , Calidad de Vida/psicología , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/psicología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Traumatismos de la Médula Espinal/cirugía , Estadística como Asunto , Estadísticas no Paramétricas
8.
J Clin Pharm Ther ; 39(2): 181-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24405193

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Itraconazole, a CYP3A inhibitor, is used for the treatment for onychomycosis with a three-cycle pulse therapy over 3 months, but its effects on in vivo CYP3A activity during the entire course remain unknown. METHODS: Urinary 6ß-hydroxycortisol/cortisol ratios were determined in 19 patients with onychomycosis, before therapy, during three cycles of itraconazole pulse therapy (200 mg twice daily for a week in each monthly cycle) and at 3 month after completion of therapy. RESULTS AND DISCUSSION: The mean 6ß-hydroxycortisol/cortisol ratio was reduced by 68% from baseline (P < 0·05) after the 1st pulse dosing, but the inhibitory effect appeared to be resolved before the next pulse dosing and at 3 months post-treatment. The magnitude of inhibition appeared in proportion to the baseline CYP3A activity. WHAT IS NEW AND CONCLUSION: The inhibitory effect of itraconazole pulse therapy on the in vivo CYP3A activity appears clinically relevant at the end of each cycle, but the inhibition resolves, on average, within 3 weeks.


Asunto(s)
Antifúngicos/uso terapéutico , Inhibidores del Citocromo P-450 CYP3A , Itraconazol/uso terapéutico , Onicomicosis/tratamiento farmacológico , Adulto , Anciano , Antifúngicos/administración & dosificación , Antifúngicos/farmacología , Monitoreo de Drogas/métodos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Hidrocortisona/análogos & derivados , Hidrocortisona/orina , Itraconazol/administración & dosificación , Itraconazol/farmacología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Quimioterapia por Pulso , Factores de Tiempo , Resultado del Tratamiento
9.
Vox Sang ; 105(3): 219-24, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23662632

RESUMEN

BACKGROUND AND OBJECTIVES: Despite growing demand for transfusion, the number of voluntary young blood donors has steadily decreased over recent years in Japan. This study aimed to develop an easy-to-use survey tool to assess barriers and motivators to blood donation among Japanese university students. MATERIALS AND METHODS: We conducted cross-sectional studies at two universities in Fukushima Prefecture, Japan, in December 2011 (Stage 1) and February 2012 (Stage 2) using self-administered questionnaires. A short list of motivators and barriers to blood donation was developed from the open-ended questions asked of 50 students in Stage 1. In the Stage 2, we asked 105 students how important these items were when they decided whether or not to donate blood. Items showing a significant difference between donors and non-donors were kept in the final list. RESULTS: Overall, 56% of the 100 participants analysed in Stage 2 were men, and ages ranged from 19 to 24 with a median of 20 years. Comparison of motivators and barriers between donors and non-donors revealed that only barrier item 8 ('Frightened by blood donation') showed a significant difference (P = 0·0006) in an expected direction and with a consistency between two universities. CONCLUSIONS: This study identified fear as being the most significant barrier to blood donation among Japanese university students, which could be used as a single convenient indicator to assess their readiness to donate. More academic and clinical efforts are needed to understand and address students' fear towards blood donation in order to increase the donor pool in Japan.


Asunto(s)
Actitud , Donantes de Sangre/psicología , Transfusión Sanguínea/estadística & datos numéricos , Miedo/psicología , Motivación , Encuestas y Cuestionarios , Pueblo Asiatico , Estudios Transversales , Femenino , Humanos , Japón , Masculino , Estudiantes , Universidades , Adulto Joven
10.
Public Health Pract (Oxf) ; 2: 100190, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36101615

RESUMEN

Objectives: There is limited evidence on methods to allocate budgets to healthcare providers under capitation schemes. The objective of this study was to construct and test models that predict outpatient visits and expenditure for each healthcare facility using subscriber data from the preceding year. Study design: We used the database of the Universal Coverage Scheme in Bangkok, Thailand that stores subscriber information and healthcare service utilization data. One-percent and ten-percent random samples of subscribers were selected as training and testing groups, respectively. Methods: Using data of the training group, we constructed a model using a random forest algorithm to predict outpatient visits and expenditure in 2017 from the 2016 data. The model was applied to the testing group and facility-level predicted number of visits and expenditure were compared with actual data. Results: The identically-structured training and testing groups consisted of 37,259 and 371,650 subscribers, respectively. Approximately 25% of subscribers utilized outpatient services. The R2 for models predicting facility-level utilization rate (visits/subscribers) and expenditure per subscriber in 2017 were 0.85 and 0.75, respectively. Conclusions: The model to predict outpatient visits and expenditure performed well. Such a prediction model may be useful for allocating budgets to healthcare facilities under capitation systems.

11.
Neuroscience ; 154(2): 821-31, 2008 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-18495360

RESUMEN

Sleep mechanisms and synaptic plasticity are thought to interact to regulate homeostasis and memory formation. However, the influences of molecules that mediate synaptic plasticity on sleep are not well understood. In this study we demonstrate that mice lacking Rab3 interacting molecule 1 alpha (RIM1 alpha) (Rim1 alpha KO), a protein of the synaptic active zone required for certain types of synaptic plasticity and learning, had 53+/-5% less baseline rapid eye movement (REM) sleep compared with their wild type littermates. Also, compared with wild type littermates, exposure of the mice to an open field or to a novel object induced more robust and longer lasting locomotion suggesting altered habituation. This difference in exploratory behavior correlated with genotype specific changes in REM and deregulated release of norepinephrine in the cortex and basal amygdala of the Rim1 alpha KO mice. Also, moderate sleep deprivation (4 h), a test of the homeostatic sleep response, induced REM sleep rebound with different time course in Rim1 alpha KO and their wild type littermates. As norepinephrine plays an important role in regulating arousal and REM sleep, our data suggest that noradrenergic deficiency in Rim1 alpha KO animals impacts exploratory behavior and sleep regulation and contributes to impairments in learning.


Asunto(s)
Ambiente , Proteínas de Unión al GTP/fisiología , Norepinefrina/metabolismo , Sueño/fisiología , Estrés Psicológico/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Conducta Animal/fisiología , Corteza Cerebral/metabolismo , Oscuridad , Electroencefalografía , Luz , Ratones , Ratones Noqueados , Actividad Motora/fisiología , Norepinefrina/genética , Sueño/genética , Estrés Psicológico/genética , Sinapsis/fisiología , Telemetría
12.
Stud Mycol ; 59: 11-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18490942

RESUMEN

Understanding the nature of species" boundaries is a fundamental question in evolutionary biology. The availability of genomes from several species of the genus Aspergillus allows us for the first time to examine the demarcation of fungal species at the whole-genome level. Here, we examine four case studies, two of which involve intraspecific comparisons, whereas the other two deal with interspecific genomic comparisons between closely related species. These four comparisons reveal significant variation in the nature of species boundaries across Aspergillus. For example, comparisons between A. fumigatus and Neosartorya fischeri (the teleomorph of A. fischerianus) and between A. oryzae and A. flavus suggest that measures of sequence similarity and species-specific genes are significantly higher for the A. fumigatus - N. fischeri pair. Importantly, the values obtained from the comparison between A. oryzae and A. flavus are remarkably similar to those obtained from an intra-specific comparison of A. fumigatus strains, giving support to the proposal that A. oryzae represents a distinct ecotype of A. flavus and not a distinct species. We argue that genomic data can aid Aspergillus taxonomy by serving as a source of novel and unprecedented amounts of comparative data, as a resource for the development of additional diagnostic tools, and finally as a knowledge database about the biological differences between strains and species.

13.
Rev Sci Instrum ; 78(6): 066101, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17614645

RESUMEN

A vacuum ultraviolet spectrometer equipped with a charge coupled device and an open multichannel plate has been used to analyze the temperature of carbon and oxygen ions in the NOVA-UNICAMP tokamak. The detection system was optimized and aligned to minimize the instrumental broadening. Also, higher order diffractions of the emissions were analyzed, resulting in lower experimental errors. The ion temperature was monitored during the tokamak discharge, presenting values between 30 and 70 eV.


Asunto(s)
Iones/química , Procesamiento de Señales Asistido por Computador/instrumentación , Espectrofotometría Ultravioleta/instrumentación , Termografía/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta/métodos , Termografía/métodos , Vacio
14.
Nucleic Acids Res ; 28(9): E38, 2000 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-10756205

RESUMEN

Attempts were made to apply atomic force microscopy (AFM) imaging to the detection and mapping of the sites of base substitutions in DNA molecules. In essence, DNA fragments to be examined for possible base substitutions were mixed with an equal amount of a corresponding DNA standard and subjected to heat denaturation and subsequent annealing. The reassociated DNA was incubated with MutS protein, a protein that recognizes and binds to mismatched base pairs in duplex DNA. Bound MutS protein molecules were then detected by AFM and their positions along the DNA molecules were determined by calculating the distance from one of the DNA termini, which had been tagged with a biotin-avidin complex. Base substitutions present in DNA molecules >1 kb were effectively detected by this procedure, and the positions determined were in good agreement with the actual mutation sites. This method is quite simple, has virtually no limitations on the size of DNA fragments to be examined and requires only a very small amount of DNA sample.


Asunto(s)
Adenosina Trifosfatasas , Disparidad de Par Base , Mapeo Cromosómico , Análisis Mutacional de ADN/métodos , Proteínas de Unión al ADN , Proteínas de Escherichia coli , Microscopía de Fuerza Atómica , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/ultraestructura , Clonación Molecular , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , ADN Bacteriano/ultraestructura , Escherichia coli/genética , Proteína MutS de Unión a los Apareamientos Incorrectos del ADN
15.
Biochim Biophys Acta ; 317(2): 563-8, 1973 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-19999739

RESUMEN

N-(1-Anilinonaphthyl-4)maleimide (ANM) (m.p. 207-208.5 degrees C), nonfluorescent, reacts selectively with thiols to give addition products which are strongly fluorescent (excitation maximum 355 nm, emission maximum 448 nm, in ethanol). 0.7 mole of ANM was introduced into thiol groups of egg albumin without modifying any other amino acid residues. In the fluorescence spectra of the reaction products of ANM with thiols, the quantum yields increase and the emission maxima shift towards the blue as the solvent polarity decreases. This remarkable solvent dependence was described in terms ofZ value of the solvents. ANM is thus expected to be a useful fluorescent hydrophobic probe directed to thiol groups in protein.


Asunto(s)
Colorantes Fluorescentes/química , Maleimidas/química , Proteínas/química , Compuestos de Sulfhidrilo/química , Albúminas/química , Etanol/química , Modelos Químicos , Óvulo/metabolismo , Unión Proteica , Solventes/química , Espectrometría de Fluorescencia/métodos , Espectrofotometría Infrarroja/métodos , Agua/química
16.
Biochim Biophys Acta ; 1079(2): 229-37, 1991 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-1911846

RESUMEN

The role of aspartic acid 53 of human lysozyme (peptidoglycan N-acetylmuramoylhydrolase, EC 3.2.1.17) has been investigated by a site-directed mutagenesis. In order to clarify the importance of precise positioning of the negatively charged carboxylate group in the active site geometry, both the three-dimensional structure and the enzymatic function of glutamic acid 53 human lysozyme (Glu-53 human lysozyme) have been characterized in comparison with those of wild type enzyme. Glu-53 human lysozyme was crystallized and analysed by X-ray crystallography. No remarkable difference in the conformation of whole molecule except the side chain of 53rd residue was observed. In spite of full retention of the binding activities against either beta-1,4-linked trisaccharide of N-acetylglucosamine ((GlcNAc)3) or the corresponding hexasaccharide ((GlcNAc)6), the conversion of Asp-53 to Glu reduced the enzymatic activities against both bacterial cell substrate and p-nitrophenyl penta-N-acetyl-beta(1----4)-chitopentaoside (p-NO2-(GlcNAc)5) to a few percent of the activities of wild type enzyme. Calculation of electrostatic potential around the reaction center predicted that no significant change in pKa of Glu-35 was caused by the mutation. These results indicate that the precise positioning of the negatively charged carboxylate in the geometry of reaction center is essential for the rate enhancement in the catalytic action of lysozyme, and suggest that Asp-53 of human lysozyme participates in the catalytic action not simply in an electrostatical manner but partly in a nucleophilical manner.


Asunto(s)
Ácido Aspártico , Ácido Carbónico/química , Muramidasa/química , Sitios de Unión , Dicroismo Circular , Electricidad , Humanos , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Difracción de Rayos X
17.
J Phys Condens Matter ; 27(46): 465701, 2015 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-26510184

RESUMEN

We report the results of inelastic neutron scattering measurements on particular phonons of a superconducting (SC) Ca10Pt4As8(Fe1-x Pt x As)10 with the onset transition temperature T c ~ 33 K to investigate mainly what roles orbital fluctuation plays in Cooper pairing, where we observed a slight softening of the in-plane transverse acoustic mode corresponding to the elastic constant C 66. This softening starts at temperature T well above the SC T c, as T decreases. An anomalously strong change of the scattering intensity of in-plane optical modes was observed at the M point of the pseudo tetragonal reciprocal space in the range of 35 < ω < 40 meV with decreasing T from far above T c. Because this ω region mainly corresponds to the motion of Fe and As atoms in the FeAs planes, the finding presents information on the coupling between the orbital fluctuation of Fe 3d electrons and the lattice system, useful for studying the possible roles of orbital fluctuation in the pairing mechanism and/or the appearance of the so-called nematic phase.

18.
Neurology ; 32(10): 1151-8, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6889700

RESUMEN

In 21 normal subjects, far-field somatosensory potentials were recorded from the scalp after stimulation of the tibial nerve at the ankle (tibial SEP). With the use of a knee reference contralateral to the side of stimulation, the tibial SEP consisted of three major positive peaks, P17, P24, and P31, and three additional but inconsistent components, P11, P21, and P27. Presumable generator sources of the tibial SEP are the popliteal fossa for P11, entry to the sacral plexus for P17, the cauda equina for P21, entry to the conus medullaris for P24, the rostral spinal cord for P27, and the brainstem for P31.


Asunto(s)
Electroencefalografía/métodos , Potenciales Evocados Somatosensoriales , Nervio Tibial/fisiología , Adolescente , Adulto , Encéfalo/fisiología , Nalgas , Estimulación Eléctrica , Humanos , Rodilla , Nervio Mediano/fisiología , Columna Vertebral
19.
Neurology ; 36(5): 647-52, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3703263

RESUMEN

In 24 median nerves from 12 healthy subjects, antidromic digital sensory potentials progressively diminished in size, averaging 40.4, 37.0, 30.7, and 23.9 microV X msec with stimulation at the palm, wrist, elbow, and axilla, respectively. In contrast, compound muscle action potentials changed minimally, measuring 19.4, 19.8, 19.0, and 18.2 mV X msec, respectively. Similar studies of the ulnar and radial nerves showed identical trends. Physiologic temporal dispersion can mimic conduction block of sensory nerves by summating the peaks of opposite polarity generated by fast- and slow-conducting axons. This type of cancellation affects muscle responses much less because motor unit potentials of longer duration superimpose nearly in phase, given the same latency shift as the sensory potentials.


Asunto(s)
Potenciales de Acción , Nervio Mediano/fisiología , Nervio Radial/fisiología , Nervio Cubital/fisiología , Adulto , Brazo , Electromiografía , Humanos , Nervio Mediano/anatomía & histología , Persona de Mediana Edad , Músculos/fisiología , Conducción Nerviosa , Nervio Radial/anatomía & histología , Nervio Cubital/anatomía & histología
20.
Biotechniques ; 23(2): 300-3, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9266087

RESUMEN

We have shown that an automated DNA sequencer is applicable to fluorescence-based detection of fragments in DNase I footprinting. We demonstrated the potential of long-range and highly sensitive DNase I footprinting taking advantage of an infrared-fluorescence automated DNA sequencer. Footprints of human transcription factor SpI were reproducibly detected ranging approximately between 100 and 750 bp on both strands of an 895-bp DNA fragment in a single electrophoresis run. We developed techniques in data collection and subsequent image processing for highly sensitive detection. Less than 0.1 footprinting unit (fpu: approximately 4.5 ng) of SpI was detected using 3.1 fmol of a 512-bp DNA fragment. This is greater than 10-fold increase in sensitivity over what has previously been reported by visible dye fluorescence DNA sequencers. This method will be very important in systematic analysis of transcription regulatory regions and in large-scale analysis of the transcription process.


Asunto(s)
Huella de ADN/métodos , Desoxirribonucleasa I , Análisis de Secuencia de ADN/métodos , ADN/análisis , Humanos , Sensibilidad y Especificidad , Análisis de Secuencia de ADN/instrumentación , Factor de Transcripción Sp1/genética , Espectrofotometría Infrarroja
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