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1.
Osteoporos Int ; 33(4): 889-899, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34797391

RESUMEN

This population-based cohort study with a 3-year follow-up revealed that the annual incidence rates of vertebral fracture (VF) and severe VF (sVF) were 5.9%/year and 1.7%/year, respectively. The presence of mild VF at the baseline was a significant risk factor for incident sVF in participants without prevalent sVF. INTRODUCTION: This study aimed to estimate the incidence of morphometric vertebral fracture (VF) and severe VF (sVF) in men and women and clarify whether the presence of a mild VF (mVF) increases the risk of incident sVF. METHODS: Data from the population-based cohort study, entitled the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study, were analyzed. In total, 1190 participants aged ≥ 40 years (mean age, 65.0 ± 11.2) years completed whole-spine lateral radiography both at the third (2012-2013, baseline) and fourth surveys performed 3 years later (2015-2016, follow-up). VF was defined using Genant's semi-quantitative (SQ) method: VF as SQ ≥ 1, mVF as SQ = 1, and sVF as SQ ≥ 2. Cumulative incidence of VF and sVF was estimated. Multivariate logistic regression analyses were performed to evaluate risk factors for incident sVF. RESULTS: The baseline prevalence of mVF and sVF were 16.8% and 6.0%, respectively. The annual incidence rates of VF and sVF were 5.9%/year and 1.7%/year, respectively. The annual incidence rates of sVF in participants without prevalent VF, with prevalent mVF, and with prevalent sVF were 0.6%/year, 3.8%/year, and 11.7%/year (p < 0.001), respectively. Multivariate logistic regression analyses in participants without prevalent sVF showed that the adjusted odds ratios for incident sVF were 4.12 [95% confident interval 1.85-9.16] and 4.53 [1.49-13.77] if the number of prevalent mVF at the baseline was 1 and ≥ 2, respectively. CONCLUSIONS: The annual incidence rates of VF and sVF were 5.9%/year and 1.7%/year, respectively. The presence of prevalent mVF was an independent risk factor for incident sVF.


Asunto(s)
Osteoartritis , Osteoporosis , Fracturas de la Columna Vertebral , Adulto , Anciano , Densidad Ósea , Estudios de Cohortes , Femenino , Humanos , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Prevalencia , Factores de Riesgo , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología
3.
Clin Exp Allergy ; 45(1): 249-54, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25207855

RESUMEN

BACKGROUND: Studies suggest that siblings of children with peanut allergy (PNA) have a higher prevalence of PNA than the general population. OBJECTIVES: The Canadian Peanut Allergy Registry was used to assess the percentage of siblings of registered index PNA children who were 1) never exposed to peanut or 2) reportedly diagnosed with PNA by a physician without either a history of allergic reaction or a confirmatory testing. Sociodemographic and clinical factors that may be associated with either outcome were evaluated. METHODS: Parents completed a questionnaire on siblings' sociodemographic characteristics, exposure and reaction to peanut, confirmatory tests performed and whether PNA had been diagnosed. RESULTS: Of 932 Registry families, 748 families responded, representing 922 siblings. 13.6% of siblings had never been exposed to peanut, 70.4% (n = 88) of which were born after the index child. Almost 9% of siblings (80) were reported as PNA, but almost half of this group had no history of an allergic reaction to peanut, including five children who also had no testing to confirm PNA. Of these 5, 4 were born after PNA diagnosis in the index child. In a multivariate regression analysis for siblings at least 3 years old, those born after PNA diagnosis in the index child were more likely to have never been exposed to peanut. In a univariate analysis, siblings born after the diagnosis of PNA in the index child were more likely to be diagnosed with PNA without supportive history or confirmatory testing. CONCLUSIONS AND CLINICAL RELEVANCE: These data estimate that more than 10% of siblings of PNA patients will avoid peanut and that siblings born after the diagnosis of PNA in an index child are more likely to have never been exposed. Educational programs and guidelines that caution against unnecessary avoidance are required.


Asunto(s)
Arachis , Hipersensibilidad al Cacahuete/diagnóstico , Hipersensibilidad al Cacahuete/epidemiología , Sistema de Registros , Hermanos , Encuestas y Cuestionarios , Adolescente , Canadá/epidemiología , Niño , Femenino , Humanos , Masculino
4.
Allergy ; 68(12): 1605-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24410784

RESUMEN

Prompt epinephrine administration is crucial in managing anaphylaxis, but epinephrine auto-injectors (EAIs) are underutilized by patients and their families. Children with peanut allergy were recruited from the Allergy Clinics at the Montreal Children's Hospital, food allergy advocacy organizations and organizations providing products to allergic individuals. Parents of children who had been prescribed an EAI were queried on whether they were fearful of using it and on factors that may contribute to fear. A majority of parents (672/1209 = 56%) expressed fear regarding the use of the EAI. Parents attributed the fear to hurting the child, using the EAI incorrectly or a bad outcome. Parents whose child had longer disease duration or a severe reaction and parents who were satisfied with the EAI training or found it easy to use were less likely to be afraid. Families may benefit from simulation training and more education on the recognition and management of anaphylaxis.


Asunto(s)
Epinefrina/administración & dosificación , Miedo , Hipersensibilidad al Cacahuete/tratamiento farmacológico , Hipersensibilidad al Cacahuete/psicología , Adolescente , Anafilaxia/prevención & control , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Inyecciones Intramusculares , Masculino , Hipersensibilidad al Cacahuete/epidemiología , Factores de Riesgo
5.
Int Arch Allergy Immunol ; 160(1): 27-36, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22948082

RESUMEN

BACKGROUND: Airway viral infections provoke exacerbations of asthma and chronic obstructive pulmonary disease. B7-H1 is a costimulatory molecule that is implicated in an escape mechanism of viruses from host immune systems. This escape may be associated with the persistence of viral infection and lead to exacerbation of underlying diseases. We have shown that an analog of viral double-stranded RNA, polyinosinic-polycytidylic acid (poly IC), upregulated the expression of B7-H1 on airway epithelial cells, an effect which was corticosteroid-resistant. We investigated the effects of corticosteroids plus long-acting ß(2)-agonists (LABAs; fluticasone/salmeterol or budesonide/formoterol) on the expression of B7-H1. METHODS: BEAS-2B cells and primary airway epithelial cells were stimulated with poly IC or respiratory syncytial virus. The expression of B7-H1 was assessed by flow cytometry. RESULTS: Poly IC upregulated the expression of B7-H1, which was suppressed by high-concentration corticosteroids but not by LABAs. The upregulation was suppressed by very low-concentration corticosteroids when used in combination with LABAs. Their combination also suppressed the virus-induced upregulation of B7-H1. Poly IC stimulation induced the nuclear translocation of nuclear factor ĸB (NF-ĸB). Inhibitors of NF-ĸB activation prevented the poly IC-induced upregulation of B7-H1. Low-concentration corticosteroids in combination with LABAs enhanced the de novo induction of IĸBα, the endogenous inhibitor of NF-ĸB activation. CONCLUSIONS: Fluticasone/salmeterol or budesonide/formoterol attenuate the virus-associated upregulation of B7-H1 on airway epithelial cells via suppression of NF-ĸB activation.


Asunto(s)
Corticoesteroides/farmacología , Agonistas de Receptores Adrenérgicos beta 2/farmacología , Antígeno B7-H1/metabolismo , Poli I-C/farmacología , Mucosa Respiratoria/metabolismo , Albuterol/análogos & derivados , Albuterol/farmacología , Androstadienos/farmacología , Budesonida/farmacología , Línea Celular , Combinación de Medicamentos , Etanolaminas/farmacología , Combinación Fluticasona-Salmeterol , Fumarato de Formoterol , Humanos , Proteínas I-kappa B/metabolismo , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Mucosa Respiratoria/patología , Mucosa Respiratoria/virología , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/metabolismo , Virus Sincitiales Respiratorios/patogenicidad , Regulación hacia Arriba
6.
Allergy Asthma Clin Immunol ; 19(1): 89, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37833754

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects children and adults. Poor treatment adherence in AD requires interventions to promote self-management; patient education in chronic diseases is key to self-management. Many international AD management guidelines published to date include a recommendation for educating patients as part of their treatment but there are no formal recommendations on how to deliver this knowledge. MAIN: We performed a scoping review to map the existing literature on patient education practices in AD and to highlight the clinical need for improved patient education in AD. The literature search was performed with the online databases MEDLINE, Embase, Grey Matters, ClinicalTrails.gov and the International Clinical Trials Registry Platform (ICTRP). The search strategy yielded 388 articles. Of the 388 articles screened, 16 studies met the eligibility criteria, and the quantitative data was summarized by narrative synthesis. The majority of studies were randomized controlled trials conducted in Europe, Asia and North America. Since 2002, there have been limited studies evaluating patient education in the treatment of AD. Frequent education methods used included group-based educational programs, educational pamphlets, individual consultations and online resources. Education was most commonly directed at caregivers and their children. Only one study compared the efficacy of different education methods. In all included studies, the heterogenous nature of outcome measures and study design limited the consistency of results. Despite the heterogeneity of studies, patient education was shown to improve quality of life (QoL), disease severity and psychological outcomes in AD patients. CONCLUSION: This scoping review highlights that patient education is effective in a variety of domains relevant to AD treatment. Further comparative studies and randomized trials with longer-term follow-up are needed to provide validated and consistent patient education recommendations for AD; these may depend on age and population.

7.
Diabet Med ; 29(7): e138-41, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22356209

RESUMEN

BACKGROUND: Insulinoma is a tumour of insulin-producing cells of the pancreas and is known to be one of the causes of hypoglycaemia. Usually, appropriate removal of the insulinoma results in normalization of blood glucose levels. However, we found novel cases of insulinoma, in which hyperglycaemia developed soon after resection of the insulinoma. CASE REPORT: We encountered two patients with repeated hypoglycaemia caused by insulinoma. Following removal of the insulinoma, unanticipated hyperglycaemia was observed in both patients. Thereafter, their blood tests revealed low levels of serum C-peptide and high titres of anti-glutamic acid decarboxylase antibody, indicating concomitant Type 1 diabetes. Indeed, histological examination of the resected specimen revealed that one patient showed insulitis in non-tumorous pancreatic tissue in which ß-cells had already disappeared. Moreover, inflammatory cells infiltrated the insulinoma, as if it were insulitis of Type 1 diabetes, suggesting the existence of anti-islet autoimmunity. CONCLUSION: These are first cases of insulinoma associated with underlying Type 1 diabetes. Physicians should be aware of the possibility that insulinoma may mask Type 1 diabetes, and measurement of anti-islet autoantibodies may be helpful to find underlying Type 1 diabetes, such as in these cases. It is pathologically interesting that the immune cell infiltration into insulinoma may be suggestive of anti-islet autoimmunity.


Asunto(s)
Autoanticuerpos/sangre , Diabetes Mellitus Tipo 1/diagnóstico , Hiperglucemia/diagnóstico , Insulinoma/diagnóstico , Islotes Pancreáticos/inmunología , Neoplasias Pancreáticas/diagnóstico , Adulto , Anciano , Péptido C/sangre , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/inmunología , Diagnóstico Diferencial , Femenino , Humanos , Hiperglucemia/sangre , Hiperglucemia/inmunología , Insulinoma/sangre , Insulinoma/inmunología , Masculino , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/inmunología
9.
Water Sci Technol ; 62(8): 1807-12, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20962396

RESUMEN

Underground is an important space that supports function of cities, such as subways, shopping malls and basement parking. However in consequence a new type of disaster, the "urban flood" menaces these spaces. In the last decade, urban floods struck Tokyo, Nagoya and Fukuoka. When underground inundation occurs, people must evacuate to the ground as soon as possible. But, when such an inundation situation happens, aged persons may not be able to evacuate quickly to ground level. In this paper, the method of safety assessment for aged persons is discussed on the experimental results and flood simulation data in an underground space. As a criterion of the safety evacuation, the specific force per unit width is used in this study. From the result of experiments, it is difficult to implement safety evacuation when the specific force per unit width is over 0.100 m(2) for the aged male.


Asunto(s)
Planificación en Desastres/métodos , Inundaciones , Modelos Teóricos , Trabajo de Rescate/métodos , Urbanización , Anciano , Anciano de 80 o más Años , Simulación por Computador , Humanos , Japón , Seguridad , Caminata , Movimientos del Agua
10.
Physiol Res ; 69(5): 861-870, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-32901491

RESUMEN

The effects of exercise on mechanical hyperalgesia, joint contracture, and muscle injury resulting from immobilization are not completely understood. This study aimed to investigate the effects of cyclic stretching on these parameters in a rat model of chronic post-cast pain (CPCP). Seventeen 8-week-old Wistar rats were randomly assigned to (1) control group, (2) immobilization (CPCP) group, or (3) immobilization and stretching exercise (CPCP+STR) group. In the CPCP and CPCP+STR groups, both hindlimbs of each rat were immobilized in full plantar flexion with a plaster cast for a 4-week period. In the CPCP+STR group, cyclic stretching exercise was performed 6 days/week for 2 weeks, beginning immediately after cast removal prior to reloading. Although mechanical hyperalgesia in the plantar skin and calf muscle, ankle joint contracture, and gastrocnemius muscle injury were observed in both immobilized groups, these changes were significantly less severe in the CPCP+STR group than in the CPCP group. These results clearly demonstrate the beneficial effect of cyclic stretching exercises on widespread mechanical hyperalgesia, joint contracture, and muscle injury in a rat model of CPCP.


Asunto(s)
Dolor Crónico/rehabilitación , Contractura/rehabilitación , Hiperalgesia/rehabilitación , Músculo Esquelético/fisiología , Condicionamiento Físico Animal/métodos , Animales , Moldes Quirúrgicos , Dolor Crónico/etiología , Dolor Crónico/patología , Contractura/etiología , Contractura/patología , Modelos Animales de Enfermedad , Humanos , Hiperalgesia/etiología , Hiperalgesia/patología , Inmovilización , Masculino , Ratas , Ratas Wistar
11.
J Food Prot ; 71(7): 1460-4, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18680947

RESUMEN

A total of 353 samples of 29 types of seafood were tested for Salmonella prevalence and total microbial population. Salmonella enterica serotype Weltevreden was isolated from 2 of 47 black tiger prawn samples. The contamination levels of Salmonella were in a range of <30 to 40 most probable number per 100 g. In addition, one sample of black tiger prawns and two samples of white shrimp were positive for Salmonella invA gene on PCR assay. Although the mean aerobic bacterial count was greater than 4 log CFU/g in most of the sample types, those in the two Salmonella-isolated samples of black tiger prawn were 7.48 and 5.18 log CFU/g, respectively. These results indicate the possibility that shrimp and prawns contribute to foodborne infections. The improvement of seafood quality is an important issue, and the information on contamination by pathogens should be provided as feedback to the originating country, with the aim of increasing safety.


Asunto(s)
Contaminación de Alimentos/análisis , Salmonella/aislamiento & purificación , Alimentos Marinos/microbiología , Mariscos/microbiología , Animales , Recuento de Colonia Microbiana/métodos , Seguridad de Productos para el Consumidor , Microbiología de Alimentos , Humanos , Japón , Prevalencia , Salmonella/crecimiento & desarrollo , Salmonella enterica/crecimiento & desarrollo , Salmonella enterica/aislamiento & purificación
12.
Obes Rev ; 19(11): 1557-1568, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30047228

RESUMEN

BACKGROUND: Work-related psychosocial factors have been associated with metabolic syndrome. However, no systematic reviews or meta-analyses have evaluated this association. METHODS: A systematic literature search was conducted, using PubMed, Embase, PsycINFO, PsycARTICLES and the Japan Medical Abstracts Society. Eligible studies included those that examined the previously mentioned association; had a longitudinal or prospective cohort design; were conducted among workers; provided sufficient data for calculating odds ratios, relative risks or hazard ratios with 95% confidence intervals; were original articles in English or Japanese; and were published no later than 2016. Study characteristics, exposure and outcome variables and association measures of studies were extracted by the investigators independently. RESULTS: Among 4,664 identified studies, 8 were eligible for review and meta-analysis. The pooled risk of adverse work-related stress on metabolic syndrome onset was significant and positive (RR = 1.47; 95% CI, 1.22-1.78). Sensitivity analyses limiting only the effects of job strain and shift work also indicated a significant positive relationship (RR = 1.75; 95% CI, 1.09-2.79; and RR = 1.59; 95% CI, 1.00-2.54, P = 0.049 respectively). CONCLUSION: This study reveals a strong positive association between work-related psychosocial factors and an elevated risk of metabolic syndrome onset. The effects of job strain and shift work on metabolic syndrome appear to be significant.


Asunto(s)
Síndrome Metabólico/psicología , Lugar de Trabajo/psicología , Humanos
13.
Biochim Biophys Acta ; 1179(2): 109-16, 1993 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-8218352

RESUMEN

Upon exposure to heat shock, non-thermotolerant (NT) HeLa cells transiently synthesize a large amount of 70-kDa heat-shock protein (hsp70), whereas thermotolerant (TT) cells synthesize a small amount of hsp70. When the hsp70 mRNA of HeLa cells was analyzed, it became apparent that hsp70 mRNA in TT cells did not increase following heat shock, whereas hsp70 mRNA in NT cells did increase dramatically. A further analysis of the activation of the heat-shock transcription factor (HSF) showed that significant activation of HSF was observed immediately after heat shock in both NT and TT cells. However, activated HSF was rapidly repressed in the TT cells, but not in the NT cells. Thus, the decreased induction of hsp70 synthesis observed in the TT HeLa cells may be due to the immediate repression of activated cellular HSF, which probably results in the reduced induction of hsp70 mRNA. The hsp70 content in the TT cells was usually higher than in the NT cells. However, after heat-shock treatment, the hsp70 content of the NT cells increased to nearly the level of the TT cells concomitant with the repression of hsp70 synthesis. The association of activated HSF with hsp70 was observed in both NT and TT cells, and the amount of HSF-hsp70 complex within the cell increased in proportion to the increase in hsp70 in the cells. These findings strongly suggest that the activity of HSF is negatively regulated by the intracellular content of hsp70 in these cells. Furthermore, in vitro experiments on the activation of HSF suggest that HSFs of NT and TT cells may have different properties, or an unknown factor may exist which regulates HSF activation in these cells.


Asunto(s)
Células HeLa/metabolismo , Proteínas de Choque Térmico/biosíntesis , Calor , Secuencia de Bases , Extractos Celulares , Regulación de la Expresión Génica , Proteínas de Choque Térmico/genética , Humanos , Datos de Secuencia Molecular , ARN Mensajero/biosíntesis , Factores de Transcripción/metabolismo
14.
J Mol Biol ; 285(4): 1537-47, 1999 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-9917395

RESUMEN

The rotation of the Na+-driven flagellar motor is specifically and strongly inhibited by phenamil, an amiloride analog. Here, we provide the first evidence that phenamil interacts directly with the Na+-channel components (PomA and PomB) of the motor. The alterations in Mpar (motility resistant to phenamil) strains were mapped to the pomA and/or pomB genes. We cloned and sequenced pomA and pomB from two Mpar strains, NMB205 and NMB201, and found a substitution in pomA (Asp148 to Tyr; NMB205) and in pomB (Pro16 to Ser; NMB201). Both residues are predicted to be near the cytoplasmic ends of the putative transmembrane segments. Mutational analyses at PomA-Asp148 and PomB-Pro16 suggest that a certain structural change around these residues affects the sensitivity of the motor to phenamil. Co-expression of the PomA D148Y and PomB P16S proteins resulted in an Mpar phenotype which seemed to be less sensitive to phenamil than either of the single mutants, although motility was more severely impaired in the absence of inhibitors. These results support the idea that PomA and PomB interact with each other and suggest that multiple residues, including Asp148 of PomA and Pro16 of PomB, constitute a high-affinity phenamil-binding site at the inner face of the PomA/PomB channel complex.


Asunto(s)
Amilorida/análogos & derivados , Flagelos/efectos de los fármacos , Flagelos/fisiología , Proteínas Motoras Moleculares/efectos de los fármacos , Proteínas Motoras Moleculares/genética , Sodio/metabolismo , Amilorida/farmacología , Secuencia de Aminoácidos , Proteínas Bacterianas , Secuencia de Bases , Sitios de Unión/genética , Cartilla de ADN/genética , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Modelos Moleculares , Proteínas Motoras Moleculares/fisiología , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Conformación Proteica , Canales de Sodio/efectos de los fármacos , Canales de Sodio/genética , Canales de Sodio/fisiología , Vibrio/efectos de los fármacos , Vibrio/genética , Vibrio/fisiología
15.
J Dent Res ; 84(5): 456-61, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15840783

RESUMEN

Oral treponemes are well-known as causative agents of periodontal diseases; however, the details have not been fully clarified. Here, we examined the effects of Treponema medium glycoconjugate on the activation of human gingival fibroblasts using phenol-water extracts from Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum subsp. nucleatum, and Actinobacillus actinomycetemcomitans. The phenol-water extracts activated human gingival fibroblasts to mediate IL-8 production, as well as IL-8 mRNA expression, phosphorylation of p38 mitogen-activated protein kinase, and expression of intercellular adhesion molecule-1. T. medium glycoconjugate exhibited no activation of human gingival fibroblasts, while phenol-water extract-induced activation of human gingival fibroblasts was clearly inhibited by T. medium glycoconjugate. Furthermore, binding of biotinylated phenol-water extracts to CD14 in the presence of LPS-binding protein was blocked with T. medium glycoconjugate. These results suggest that T. medium glycoconjugate has an inhibitory effect on host cell activation by periodontopathic bacteria caused by binding to CD14- and LPS-binding protein.


Asunto(s)
Extractos Celulares/farmacología , Fibroblastos/efectos de los fármacos , Encía/efectos de los fármacos , Glicoconjugados/farmacología , Bacterias Gramnegativas/fisiología , Enfermedades Periodontales/microbiología , Treponema/fisiología , Proteínas de Fase Aguda/inmunología , Aggregatibacter actinomycetemcomitans/fisiología , Proteínas Portadoras/inmunología , Células Cultivadas , Fibroblastos/inmunología , Fusobacterium nucleatum/fisiología , Encía/citología , Encía/inmunología , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Interleucina-8/biosíntesis , Receptores de Lipopolisacáridos/inmunología , Lipopolisacáridos/inmunología , Glicoproteínas de Membrana/inmunología , Fenoles , Fosforilación , Porphyromonas gingivalis/fisiología , Prevotella intermedia/fisiología , Treponema/inmunología , Agua , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
16.
Med Biol Eng Comput ; 43(3): 319-24, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16035218

RESUMEN

The digital imaging and communications in medicine (DICOM) standard proposed the grey-scale standard display function (GSDF) as a calibration tool for making the gradation characteristic of a radiographic output image consistent. This is designed in such a manner that the contrast visually recognised by observers (called psychophysical contrast) becomes a constant for all digital driving levels. The DICOM standard calls such an ideal characteristic perceptual linearisation. The psychophysical gradient that can express the psychophysical contrast was introduced for the evaluation of the GSDF using a liquid crystal display monitor. Investigations regarding its ability to yield a constant psychophysical contrast, independent of the digital driving level change and under an actual observation environment, such as for clinical radiographic diagnosis in hospital, were carried out. The psychophysical gradients of the GSDF were obtained for two kinds of observation environment: one was a restricted environment such as in a dark room, under steady-state adaptation, using the sinusoidal grading pattern corresponding to the peak frequency of the human eye response. The other was an actual environment reflecting that encountered during clinical diagnosis in a hospital. As a result, the psychophysical gradient under the restricted environment became almost constant and independent of the change in digital driving level, i.e. perceptual linearisation could be satisfied. Furthermore, under the actual observation environment, the psychophysical gradient decreased gradually with the increase in digital driving level, i.e. the perceptual linearisation could not be satisfied. The percentage decrease in the value of the psychophysical gradient at the maximum luminance area was approximately 60% compared with that at the minimum luminance area. Accordingly, the GSDF is unsuitable as a calibration tool for the liquid crystal display monitor, which will be used in actual clinical diagnosis, as it cannot achieve 'perceptual linearisation' under the actual environment. For the purpose of clinical diagnosis, it is necessary to enlarge the physical gradient of GSDF further in the high digital driving level range (which relates to a high luminance area) to give an approximation that is as close to the idealised form as possible.


Asunto(s)
Terminales de Computador/normas , Presentación de Datos/normas , Intensificación de Imagen Radiográfica/normas , Calibración , Sensibilidad de Contraste , Humanos , Psicofísica , Umbral Sensorial
17.
Pharmazie ; 60(3): 201-4, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15801673

RESUMEN

E5880, a novel platelet activating factor receptor antagonist, was dispersed in water for use in an injectable formulation and the physicochemical properties of the preparation were characterized. The critical concentration for formation of micelles was 0.12 mM. Using area per molecule data, the critical packing parameter was calculated, indicating that the structure of the micelles was spherical and that each micelle containes 49 molecules. The diameter of the micelles was 8.1 nm. Attractive interactions occurred between E5880 molecules in the micelle. The hydrocarbon region in the micelle was more rigid and less hydrated than that of other surfactants, stearyltrimethylammonium chloride and cetyltrimethylammonium chloride.


Asunto(s)
Piperidinas/química , Factor de Activación Plaquetaria/antagonistas & inhibidores , Compuestos de Piridinio/química , Algoritmos , Fenómenos Químicos , Química Farmacéutica , Química Física , Lípidos/química , Micelas , Tamaño de la Partícula , Propiedades de Superficie
18.
Gene ; 158(1): 87-90, 1995 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-7789816

RESUMEN

A 2.5-kb EcoRI fragment containing the aspartase-encoding gene (aspA) of Brevibacterium flavum MJ233 was cloned into plasmid pUC18 using Southern hybridization with the Escherichia coli aspA gene as a probe. The complete nucleotide (nt) sequence of the cloned DNA indicated that the deduced gene product of the Br. flavum aspA is composed of 526 amino acids (aa). Comparison of the aa sequence to the corresponding sequences from E. coli, Bacillus subtilis and Pseudomonas fluorescens revealed 63, 47 and 57% homology, respectively. The aspA product was determined to have a size of approx. 57 kDa by SDS-PAGE.


Asunto(s)
Aspartato Amoníaco-Liasa/genética , Brevibacterium/enzimología , Secuencia de Aminoácidos , Secuencia de Bases , Brevibacterium/genética , Clonación Molecular , ADN Bacteriano , Escherichia coli/genética , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
19.
Gene ; 139(1): 99-103, 1994 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-8112597

RESUMEN

A conserved domain of the secY genes from Bacillus subtilis, Mycoplasma capricolum and Escherichia coli was used to design degenerate oligodeoxyribonucleotides. These synthetic DNA sequences were used to screen a lambda library of Brevibacterium flavum MJ233. A 1.5-kb KpnI fragment of a recombinant lambda phage containing the secY homology from Br. flavum MJ233 was subsequently subcloned into plasmid pUC118. The complete nucleotide (nt) sequence of the cloned fragment indicated that the deduced gene product of the Br. flavum secY homolog is composed of 440 amino acids (aa) with a deduced M(r) of 47,871. Comparison of this aa sequence to the corresponding sequences from E. coli and B. subtilis revealed a high degree of conservation, and suggested that the Br. flavum secY homolog is a membrane protein containing ten transmembrane segments. In addition, we could identify, downstream from secY, a putative coding sequence of the enzyme adenylate kinase. This gene organization is identical to that observed in the B. subtilis genome.


Asunto(s)
Actinomycetales/genética , Bacillus subtilis/genética , Proteínas Bacterianas/genética , Brevibacterium/genética , Secuencia Conservada , Proteínas de Escherichia coli , Genes Bacterianos , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Secuencia de Bases , Escherichia coli/genética , Biblioteca de Genes , Prueba de Complementación Genética , Datos de Secuencia Molecular , Mycoplasma/genética , Oligodesoxirribonucleótidos , Plásmidos , Estructura Secundaria de Proteína , Canales de Translocación SEC , Homología de Secuencia de Aminoácido
20.
FEBS Lett ; 446(1): 169-72, 1999 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-10100636

RESUMEN

The effects of ubiquinone-3 (UQ) on dipalmitoylphosphatidylcholine (DPPC) membrane were studied by surface monolayer, differential scanning calorimetry (DSC) and fluorescence techniques. DPPC and UQ are proved to be freely miscible in the mixed monolayer at an air/water interface, and to be partially miscible in bulk phase, i.e. bilayer and solid phase. There is a condensing interaction between UQ and DPPC in the UQ/DPPC mixed monolayers. The solubility of UQ in the DPPC is about 20 mole% and the solubility of DPPC in UQ is about 10 mole%. The membrane fluidity of DPPC was increased by the addition of UQ and the phase transition temperature was decreased.


Asunto(s)
Membranas Artificiales , Fosfolípidos/metabolismo , Ubiquinona/metabolismo , Fluidez de la Membrana , Lípidos de la Membrana/metabolismo
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