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PURPOSE: In the past we have developed and validated the hernia-specific quality of life assessment instrument, HERQL, for groin hernias. In current study we evaluated the conceptual structure and validated HERQL for abdominal wall hernias. METHODS: Subjective quality-of-life perceptions from abdominal wall hernia patients were assessed. Clinical responsiveness was evaluated comparing treatment naïve with follow-up hernia patients. Measurement invariance between groin and abdominal wall hernias was approached with structural equation modeling (SEM). Subgroup comparisons were conducted between primary ventral and incisional hernias, as well as the presence of co-morbidity, hernia incarceration, surgical complications, and recurrent abdominal wall hernias. RESULTS: A total of 775 HERQL assessments, including 167 from abdominal wall hernias, were successfully performed. Cronbach's alpha coefficients for the summative pain, worse symptoms for treatment-naïve patients, and improving summative pain scores across the pre-operative, immediately post-operative, and post-operative 3-month assessments indicating clinical responsiveness were observed and comparable between groin and abdominal wall hernias. Configural invariance was evidenced by that the same model held true for both types of hernias with multi-group SEM, while mean structure exploration showed that abdominal wall hernia patients reported less latent summative pain (- 0.535, p < 0.0001) but worse latent quality-of-life score (0.207, p < 0.0001). Patients with peri-operative complications suffered from worse pain during mild activities (2.7 versus 1.5, p = 0.01), and patients with recurrent hernias reported compromised global health/quality of life (2 versus 1.6, p = 0.001). CONCLUSIONS: The study successfully validated and extended the clinical applicability of HERQL across distinct types of hernias. Measurement invariance was ascertained and the same HERQL construct could be administered for both abdominal wall and groin hernias in Taiwan.
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Pared Abdominal/cirugía , Herniorrafia , Calidad de Vida , Adulto , Femenino , Ingle/cirugía , Hernia Inguinal/cirugía , Hernia Ventral/cirugía , Humanos , Hernia Incisional/cirugía , Masculino , Persona de Mediana Edad , Medición de Resultados Informados por el Paciente , Periodo Posoperatorio , TaiwánRESUMEN
INTRODUCTION: The objective of this study was to assess the prevalence of young females at risk of developing eating disorders (ED) and the associated socio-demographical variables. METHODS: A set of self-administered questionnaires consisting of an Eating Attitude Test (EAT), an Eating Disorder Inventory (EDI) and a socio-demographical questionnaire was administered to 4,461 young females. Based on scores for EAT and/or EDI-drive for thinness (EDI-DT) subscale, subjects were categorised into either "normal" (NM) or "at risk" (AR) of ED. RESULTS: Mean age of the subjects was 16.7 years (range 12-26 years). The ethnic composition was 78.8 percent Chinese, 11.7 percent Malay, 6.6 percent Indian and 3 percent other ethnic groups. Prevalence of AR was 7.4 percent (95 percent confidence interval [CI] 6.7-8.2 percent). Mean EAT and EDI-DT scores for AR were significantly higher than that of NM (EAT: mean difference is 22.1, 95 percent CI 20.7-23.4, p-value is less than 0.0001; EDI-DT: mean difference is 10.9, 95 percent CI 10.5-11.4, p-value is less than 0.0001). Female Malays constituted a significantly larger proportion of AR (20.6 percent) as compared to NM (10.9 percent). AR females are more likely to use Malay as a spoken language at home (prevalence rate ratio 1.70, p-value is 0.001) and to be better educated with completion of General Certificate of Education (GCE) "O" levels. However, the parents of AR females are likely to be less well educated (below GCE "A" levels). CONCLUSION: The prevalence of females at risk of developing ED is 7.4 percent. Malay ethnic group, using Malay language at home and the educational levels of both the subjects and their parents appear to be associated with an increased risk for development of ED.
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Imagen Corporal , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Adolescente , Adulto , Índice de Masa Corporal , Niño , Estudios Transversales , Femenino , Humanos , Prevalencia , Medición de Riesgo , Factores de Riesgo , Singapur/epidemiología , Encuestas y CuestionariosRESUMEN
Enlarged iliopectineal bursitis in the hip region, which usually occurs with degenerative, infectious, or traumatic disorders, is relatively rare. Iliopectineal bursitis complicating bipolar hemiarthroplasty is even more rare. Reported here is an unusual case of a patient with an inguinal mass presenting 8 years after bipolar hemiarthroplasty. Enlarged bursitis complicating the hip prosthesis is rare and has been described only anecdotally in the literature. The enlarged iliopectineal bursa arises from the hip, and the most apparent cause of its formation is polyethylene debris. Treatment should be directed at the source of the debris intraarticularly. Wearing of the polyethylene insert was difficult to discern radiographically for this patient; it was seen on the scout film of the computed tomography of the pelvis while evaluating the enlarged bursitis. The scout film of the computed tomography and the two-dimensional reconstruction of computed tomograms of the hip may be helpful in evaluating wearing of the polyethylene insert.
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Artroplastia de Reemplazo de Cadera/efectos adversos , Bursitis/etiología , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: P maximum and P dispersion are evaluated as predictors of paroxysmal atrial fibrillation in adults. In this study, these variables are being investigated in children with secundum ASD in comparison with that of normal controls and in relation to size of ASD and the presence or absence of atrial dilation. METHODS: Ninety-four children with isolated secundum ASD (33 boys, 60 girls; mean +/- SD age at diagnosis 2.9 +/- 4.1 years) and 65 age-matched controls (mean +/- SD age 4.2 +/- 4.2 years) were evaluated. Resting 12-lead ECG was used to measure P waves from which P maximum and P dispersion (difference between maximum and minimum P-wave duration) were derived. ASD children were arbitrarily subgrouped according to ASD sizes (small: 1-3 mm, moderate: 4-7 mm, large: > or = 8 mm). The presence of right atrial dilation was noted from echocardiography. RESULTS: Children with ASD had significantly longer mean P dispersion compared to controls (P dispersion: 30.2 +/- 11.1 vs 26.4 +/- 6.6 ms, P = 0.008). Mean P maximum and P dispersion were significantly prolonged with increasing ASD size (P < 0.001). Children with right atrial dilation had significantly longer P maximum (102.3 +/- 15.2 vs 82.8 +/- 13.4 ms, P < 0.001) and larger P dispersion (36.1 +/- 12.5 vs 27.6 +/- 9.4 ms, P = 0.003) compared to those without right atrial dilation. CONCLUSION: Prolonged atrial conduction time and inhomogeneity of atrial conduction may possibly be present in children with moderate to large sized ASD and in those with atrial dilation.
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Electrocardiografía , Defectos del Tabique Interatrial/fisiopatología , Análisis de Varianza , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Preescolar , Femenino , Defectos del Tabique Interatrial/patología , Humanos , MasculinoAsunto(s)
Diarrea/terapia , Fluidoterapia/métodos , Oryza , Soluciones para Rehidratación/uso terapéutico , Niño , Preescolar , Humanos , LactanteRESUMEN
OBJECTIVES: To compare blood lipids, lipoproteins, apoproteins, fibrinogen, insulin and aerobic capacity in obese and non-obese Chinese Singaporean boys. To examine relationships between blood metabolites, body composition and aerobic capacity in these groups. DESIGN: Cross-sectional. SUBJECTS: Forty Chinese Singaporean boys aged 13-15 y. Classified as obese (n=20) or non-obese (n=20) based on adiposity (fat mass/fat free mass): >0.60=obese, <0.40=non-obese. MEASUREMENTS: Body composition (dual energy X-ray absorptiometry), waist circumference, peak oxygen consumption (VO(2) peak), serum concentrations of total cholesterol, triacylglycerol, high density lipoprotein cholesterol (HDL-C), total cholesterol/HDL-C, apoproteins AI and B, lipoprotein(a), insulin and glucose. Plasma concentration of fibrinogen. RESULTS: Obese boys had significantly (P<0.01) higher (mean+/-s.d.) concentrations of serum triacylglycerol (1.51+/-0.65 vs 1.04+/-0.34 mmol/l), serum insulin (24.1+/-11.5 vs 12.3+/-4.45 mU/l) and plasma fibrinogen (4.01+/-0.54 vs 3.35+/-0.76 g/l) than non-obese boys. Within the non-obese group plasma fibrinogen concentration was significantly related to percentage body fat (r=0.546, P<0.05). VO(2) peak relative to body mass (ml/kg/min or ml/kg(-0.67)/min) was significantly (P<0.001) lower in obese compared to non-obese boys but absolute VO(2) peak (l/min), adjusted for fat-free mass via analysis of covariance, was higher in obese than non-obese boys (P<0.01). Partial correlations revealed that none of the blood metabolites were significantly related to VO(2) peak independent of body fatness. CONCLUSIONS: Obesity was related to elevated concentrations of serum triacylglycerol, serum insulin and plasma fibrinogen in Chinese Singaporean boys. These elevated concentrations did not appear to be associated with a lower aerobic capacity (independent of body fatness) in the obese.
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Fibrinógeno/análisis , Insulina/sangre , Lípidos/sangre , Obesidad/fisiopatología , Consumo de Oxígeno/fisiología , Absorciometría de Fotón , Adolescente , Composición Corporal , Niño , Estudios Transversales , Humanos , Masculino , Obesidad/metabolismoRESUMEN
Studies have indicated that adult patients with mitral valve prolapse (MVP) may have autonomic dysfunction. The purpose of this study was to evaluate heart rate variability (HRV) in children with MVP. Sixty-seven children with MVP (ages 6 to 18 years; 30 boys and 37 girls) were consecutively studied and subdivided into those with or without symptoms. Thirty-seven normal age-matched children (17 boys and 20 girls) were studied as controls. The patients were further divided into 4 age subgroups. HRV was measured using a 24-hour Holter electrocardiogram (ECG) system (Laser SXP Holter Analysis System, Marquette Electronics, Milwaukee, WI). The ECGs were analyzed in both time domain and frequency domain (spectral analysis). Symptomatic and asymptomatic children with MVP were combined for analysis because they were not significantly different in terms of their HRV. All time-domain indices, with the exception of SDANN (SD of the mean of RR intervals in all 5-minute segments of the 24-hour ECG), were significantly lower in children with MVP than in controls. Children with MVP showed significantly lower spectral power of the high frequency (HF) and low frequency (LF) components when compared with controls. The ratio of LF to HF (LF/HF) was significantly higher in children with MVP. Similar differences were observed in the 4 age subgroups. Sex differences in HRV were observed when girls had lower HRV compared with boys. Lower time-domain and frequency-domain indices of HRV in children with MVP are suggestive of decreased parasympathetic activity and a shift in sympathovagal balance. Various factors including differences in heart rate may contribute to sex differences in HRV.
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Frecuencia Cardíaca/fisiología , Prolapso de la Válvula Mitral/fisiopatología , Adolescente , Niño , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVE: TT virus (TTV) is a newly discovered human DNA virus of uncertain clinical significance. The aim of this study was to determine the prevalence of TTV infection among blood donors in Taiwan. METHODS: Viral DNA was studied in 224 healthy blood donors and 118 deferred donors. DNA was extracted from plasma and amplified by seminested polymerase chain reaction with reported primer sets from a conserved region of the TTV genome. RESULTS: The prevalence of TTV DNA in the deferred donors was 24.6%, significantly higher than in the healthy donors (11.9%). TTV was also more prevalent in those with hepatitis B surface antigen than in those without it (p = 0.002). CONCLUSION: In comparing normal with deferred Taiwanese blood donors, hepatitis B virus infection is linked to a higher prevalence of TTV infection.
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Donantes de Sangre , Infecciones por Virus ADN/epidemiología , Torque teno virus/genética , Distribución de Chi-Cuadrado , Infecciones por Virus ADN/virología , ADN Viral/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Tamizaje Masivo , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Taiwán/epidemiologíaRESUMEN
BACKGROUND/AIMS: A cultural preference for thinness has been implicated in the development of eating disorders in Western, post-industrialised societies. In transitional societies like Singapore, a shift in expectations of ideal body size (toward thinness) may lead to an increase in eating disorders. This study investigated perceptions about body size and shape in over 200 youths living in Singapore, and the influences of adiposity, gender, Westernization and parents' education. METHODS: A self-administered questionnaire was used to gather social and cultural information from 137 males and 143 females, aged 17-22 years. It included questions relating to eating behaviour and body satisfaction from which a "preference for thinness score" was derived. Westernization was indicated by language spoken at home. Adiposity was measured by triceps skinfold and body mass index. Multiple linear regression analysis was used to assess the associations of adiposity, mother's education, father's education, and language spoken at home with the preference for thinness score. RESULTS: Dissatisfaction with body size and shape increased with tertile of adiposity among females, and thoughts about dieting and becoming thinner were present even among underweight girls. Unlike the females, the highest proportion of males satisfied with their body size and shape, was associated with the middle tertile of BMI. Speaking English at home, but not parents' education, was positively associated with body dissatisfaction after controlling for BMI. CONCLUSION: Chinese Singaporean female youths have a preference for thinness as an ideal body size. The epidemiology of eating disorders in Singapore and other newly industrialised societies warrants further investigation.
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Imagen Corporal , Obesidad/epidemiología , Delgadez/psicología , Adolescente , Adulto , Características Culturales , Femenino , Humanos , Industrias , Masculino , Prevalencia , Análisis de Regresión , Factores de Riesgo , Muestreo , Distribución por Sexo , Singapur/epidemiología , Factores Socioeconómicos , Encuestas y Cuestionarios , Delgadez/epidemiología , Mundo OccidentalRESUMEN
OBJECTIVE: For years, blood transfusion centers in Taiwan have used the Quantitative Buffy Coat (QBC(R)) Hematology System for platelet counts on capillary blood samples in the laboratory screening of apheresis donors. The system has not been evaluated for the prediction of yields in plateletpheresis. Methods : The QBC instrument was evaluated for reproducibility of platelet counts and compared with five electronic cell counters. We also collected both capillary and venous blood from voluntary donors before donation and counted platelets, comparing the QBC system and an electronic blood cell counter (Sysmex K1000). The correlation between donors' predonation platelet counts and plateletpheresis yields was analyzed. RESULTS: The R values for platelet counts between the QBC Hematology System and other electronic counters are lower (0.759-0. 890) than among the electronic counters (0.929-0.973). The mean capillary platelet count and the mean venous platelet count were 241. 9+/-50.3x10(3)/microl and 233.2 +/-47.9x10(3)/microl by the QBC system, and 244.9+/-54.1x10(3)/microl and 218.9+/-46.5x10(3)/microl by the Sysmex K1000, respectively. Linear regression analysis showed that platelet yields correlated well with donors' predonation platelet counts using the Sysmex K1000 counter (R = 0.777- 0.890, p<0.001), but not with the QBC system (R = 0.326 approximately 0.755, p<0.05). CONCLUSION: The QBC Hematology System is not accurate enough to determine predonation platelet counts that are to be used for calculating the number of processing cycles for plateletpheresis.
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Recuento de Plaquetas/métodos , Plaquetoferesis , Electrónica , Estudios de Evaluación como Asunto , Humanos , Modelos Lineales , Recuento de Plaquetas/instrumentación , Plaquetoferesis/normas , Reproducibilidad de los ResultadosRESUMEN
The purpose of the study was to evaluate, in a clinical study over 2 years, the deterioration of two glass ionomer cements used with the atraumatic restorative treatment (ART) technique or approach. Fifty-five Fuji IX and 45 ChemFil Superior restorations were placed randomly in 23 adult patients, mainly in small occlusal preparations in molar teeth. The restorations were placed in a dental hospital by one dentist using the ART technique. Photographs, radiographs and replicas were obtained at baseline and subsequent recalls. Both cements were easy to mix and place, but the radiolucency of ChemFil Superior was a disadvantage. Both cements also showed early high losses of sealant and restorative material. After 2 years, 34.5% of the sealants appeared to be completely lost, with caries recorded in 5.3% of the exposed fissures. In some instances, these small lesions may have been present, but not detected clinically, at the time of sealing. Restoration failures of 7.0% were from wear and fracture of the cements and recurrent caries. Mean cumulative wear was 83.1 microm for Fuji IX and 104.0 microm for ChemFil Superior, which was not statistically significant. The cements became darker after their placement to more closely match the restored teeth, but there were few exact matches. There was no surface staining and only minor marginal discrepancies and staining associated with the restorations. Although the short-term clinical performance of the two glass ionomer cements was reasonable, the materials require further improvements in their mechanical properties, to reduce sealant losses and wear. The cements evaluated appear suitable for restricted use only, in posterior teeth.
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Fracaso de la Restauración Dental , Restauración Dental Permanente/métodos , Cementos de Ionómero Vítreo , Adulto , Adaptación Marginal Dental , Alisadura de la Restauración Dental , Femenino , Humanos , Masculino , Diente Molar , Estadísticas no ParamétricasRESUMEN
PURPOSE: We retrospectively evaluated the usefulness of sonography in the diagnostic assessment of children with abdominal pain. METHODS: From July 1988 to October 1996, 676 children who had abdominal pain and were referred for sonography underwent abdominal and pelvic sonographic examination. Of these, 644 children had recurrent abdominal pain (RAP) and 32 children had acute or subacute abdominal pain (ASAP). The mean ages and relative risks of underlying abnormalities were calculated for children with RAP and ASAP. RESULTS: Abdominal abnormalities were sonographically detected in 10 children with RAP (2%), a significantly lower incidence than in children with ASAP (56%, p < 0.0001), with a relative risk of 0.028 (95% CI, 0.014-0.055). In the RAP group, an underlying abnormality was more likely (p < 0.001) to be sonographically detected in children who had atypical clinical features (5 of 46%; 11%) than in those with typical clinical features (5 of 598; 1%), with a relative risk of 12.94 (95% CI, 3.90-43.30). Children with RAP were found to have hydronephrosis (3), urinary cystitis (2), duplex kidney (1), hypoplastic low-lying kidney (1), choledochal cyst (1), ovarian teratoma (1), and gross gaseous distention with fecal masses (1). Children with ASAP had urinary cystitis (4), intussusception (2), appendicitis (2), appendiceal abscess (1), perforated gut with ascites (1), gut duplication (1), thickened gut wall with fluid from severe gastroenteritis (1), gross gaseous distention with fecal masses (1), hepatosplenomegaly (1), cholecystitis (1), gross hydronephrosis (1), Wilms' tumor (1), and abdominal neuroblastoma (1). CONCLUSIONS: Abdominal sonography is useful in children with ASAP. Although an underlying abnormality was rarely found in children with RAP, children who have RAP with atypical clinical features should have sonographic screening. If no abnormalities are found, the normal sonograms may be reassuring to parents.
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Abdomen Agudo/diagnóstico por imagen , Abdomen Agudo/etiología , Dolor Abdominal/diagnóstico por imagen , Dolor Abdominal/etiología , Adolescente , Análisis de Varianza , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Factores de Riesgo , UltrasonografíaRESUMEN
Signal-averaged electrocardiograms (SAECGs) have been found to be influenced by sex and anthropometry in adults. The purpose of this study was to evaluate this relationship in children. Total filtered QRS duration (TQRS), duration of high-frequency, low-amplitude signals in the terminal portion of the QRS complex that were less than 40 microV (HFLA) root-mean-square voltage in the last 40 ms of the filtered QRS (RMS40) were determined by high-resolution electrocardiographic (ECG) recording (MAC 15 ECG System, Marquette Electronics, Milwaukee, WI). These parameters were correlated with age, sex, body weight, height, relative weight, body mass index, and body surface area. As HFLA and RMS40 were not normally distributed, they were logarithmically transformed for regression analysis. The best subset multiple regression procedure was used to evaluate the variables that would optimally influence SAECG measurements and to obtain regression equations for the prediction of each SAECG parameter. Although univariate analysis shows that almost all the body characteristics and age are significantly correlated with SAECGs, multiple regression analysis reveals that TQRS is significantly influenced by height (P < .0001), relative weight (P = .012), and body mass index (P = .041); HFLA is influenced by weight (P = .001), height (P = .004), and body mass index (P = .001); and RMS40 is influenced by height (P < .0001) and relative weight (P = .001). Sex is noted to significantly influence both TQRS and RMS40 (P < .0001, P = .002, respectively), while HFLA is found to be significantly related to age (P = .001). In summary, SAECGs in Chinese children are shown to be influenced by height, weight, and relative weight or body mass index, but not body surface area, while age and sex also significantly contribute to the variation of some SAECG parameters.
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Envejecimiento , Constitución Corporal , Electrocardiografía , Caracteres Sexuales , Procesamiento de Señales Asistido por Computador , Adolescente , Niño , China , Femenino , Humanos , Masculino , Valores de Referencia , Análisis de RegresiónRESUMEN
The serum lipid and lipoprotein levels of 59 obese Chinese children with a mean age of 13.0 years and mean relative weight of 164.2% were analysed. Between 40% to 54% of these children had elevated lipid and lipoprotein levels and about 78% had reduced high density lipoprotein (HDL) level when compared to healthy American and Japanese children. The obese children also had higher mean levels of total cholesterol (TC) and lower HDL compared to male adults in the local population. Those with elevated TC had higher mean relative weight (170% vs 159%, p < 0.05). In view of the close association between hyperlipidaemia and atherosclerosis, obese children should be carefully screened and managed to prevent long term morbidity and mortality of coronary artery disease.
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Pueblo Asiatico , Lípidos/sangre , Lipoproteínas/sangre , Obesidad/sangre , Adolescente , Adulto , Niño , Preescolar , China , Femenino , Humanos , MasculinoRESUMEN
The purpose of this study was to evaluate the relationship between rate-pressure product (RPP) and degree of obesity in 511 obese 7 and 12 year old Chinese children. Obesity was assessed by anthropometry and skinfold thickness. The children were defined obese by relative weight (RW) > 120%. Bodyweight (W) and height (H) were used to derive body mass index (W/H2). Brachial systolic and diastolic pressures in these children were measured by cuff sphygmomanometry. RPP was calculated by the formula: heart rate x mean arterial pressure. More obese children (RW > or = 150%) had greater mean RPP (7 year old: 6389 vs 5976 beats/min x mmHg, P < 0.05; 12 year old: 7024 vs 6686 beats/min x mmHg) than those with RW < 150%. Children in the upper 25 percentiles of RPP had significantly larger BMI (7 and 12 year olds) and RW (12 year olds), thicker biceps, triceps and subscapular skinfolds (12 year olds) (P < 0.01-< 0.05). The results indicate that RPP is, to some extent, related to the degree of obesity in obese children. The differences in RPP may imply varying degrees of hemodynamic stress to the heart. Whether such differences may contribute to the long-term development of cardiovascular morbidity in more obese individuals is uncertain.
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Presión Sanguínea , Frecuencia Cardíaca , Obesidad/fisiopatología , Antropometría , Niño , Femenino , Humanos , Masculino , Grosor de los Pliegues CutáneosRESUMEN
In the present study, A23187-induced pleurisy in mice was used to investigate the anti-inflammatory effect of magnolol, a phenolic compound isolated from Chinese medicine Hou p'u (cortex of Magnolia officinalis). A23187-induced protein leakage was reduced by magnolol (10 mg kg-1, i.p.), indomethacin (10 mg kg-1, i.p.) and BW755C (30 mg kg-1, i.p.). A23187-induced polymorphonuclear (PMN) leucocyte infiltration in the pleural cavity was suppressed by magnolol and BW755C, while enhanced by indomethacin. Like BW755C, magnolol reduced both prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) levels in the pleural fluid of A23187-induced pleurisy, while indomethacin reduced PGE2 but increased LTB4 formation. In the rat isolated peripheral neutrophil suspension, magnolol (3.7 microM) and BW755C (10 microM) also suppressed the A23187-induced thromboxane B2 (TXB2) and LTB4 formation. These results suggest that magnolol, like BW755C, might be a dual cyclo-oxygenase and lipoxygenase inhibitor. The inhibitory effect of magnolol on the A23187-induced pleurisy is proposed to be, at least partly, dependent on the reduction of the formation of eicosanoids mediators in the inflammatory site.
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Antiinflamatorios no Esteroideos/farmacología , Compuestos de Bifenilo/farmacología , Lignanos , Pleuresia/tratamiento farmacológico , Animales , Ácido Araquidónico/metabolismo , Líquidos Corporales/metabolismo , Calcimicina/toxicidad , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Leucotrieno B4/metabolismo , Ratones , Ratones Endogámicos ICR , Extractos Vegetales/farmacología , Pleura/metabolismo , Pleuresia/inducido químicamente , Pleuresia/metabolismo , Proteínas/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Molecular analogs of amino acids can be incorporated into proteins. The amino acid analog selenomethionine (SeMet) has been shown to be efficiently incorporated into the proteins of growing Escherichia coli. SeMet-containing proteins are known to produce sufficiently strong anomalous scatter permitting the solution of the selenomethionyl crystal structure by multiwavelength anomalous diffraction (MAD) techniques. The recombinant protein chosen for these studies is mature, truncated neutrophil collagenase (rmNC-t). The rmNC-t protein is a monomer of 163 amino acid residues featuring one active site and two Met residues. We developed a T7 polymerase expression system allowing incorporation of SeMet into rmNC-t protein produced in E. coli. Substitution of Met with SeMet was accomplished by culturing E. coli DL41(DE3), a SeMet-tolerant strain with metA lesion, in a defined medium containing SeMet as the sole source of Met. The SeMet-labeled rmNC-t was isolated from inclusion bodies by solubilizing in urea, purified by anion column chromatography, and then refolded in the presence of Ca2+ and Zn2+. Analysis of SeMet-labeled rmNC-t demonstrated that Met replacement was 100%. Enzymatic characterization revealed no obvious differences in activity or inhibitor binding between rmNC-t and the SeMet-labeled product. We have produced pure, active SeMet-labeled rmNC-t in sufficient quantities for macromolecular crystallography studies.
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Colagenasas/genética , Escherichia coli/genética , Selenometionina/metabolismo , Secuencia de Bases , Colagenasas/aislamiento & purificación , Colagenasas/metabolismo , Cartilla de ADN , Humanos , Hidrólisis , Cinética , Metaloproteinasa 8 de la Matriz , Datos de Secuencia Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Selenio/metabolismoRESUMEN
Human neutrophil collagenase (HNC) is a member of a family of matrix metalloproteinases (MMP). HNC is capable of cleaving all three alpha-chains of types I, II and III collagens. In rheumatoid and osteo-arthritis, MMP members have been implicated in the pathology associated with these diseases due to the accelerated breakdown of the extracellular matrix of articular cartilage. A cDNA coding for the HNC catalytic domain (lacking both the propeptide and C-terminal fragments) was sub-cloned into the pETlla prokaryotic expression vector. The cloned fragment encodes a protein that extends from amino acids (aa) Met100 through Gly262 of the full-length proenzyme, which as a result, would not require proteolytic or chemical activation. The HNC construct was expressed in Escherichia coli and recombinant mature, truncated neutrophil collagenase (re-mNC-t) was produced at high levels (approx. 30% of total bacterial protein). The re-mNC-t protein was extracted from inclusion bodies by solubilization in 6 M urea, followed by ion-exchange chromatography. The protein was refolded to an active conformation in the presence of Ca2+ and Zn2+. A final purification step on size-exclusion chromatography yielded 30 mg per liter of active re-mNC-t with minor autodegradative products. Alternatively, hydroxamate affinity chromatography was used to obtain pure, non-degraded re-mNC-t (20-25 mg per liter). The catalytic activity of re-mNC-t was abolished by known MMP inhibitors and the Ki measurement against actinonin was similar to that of HNC prepared from human blood.
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Colagenasas/genética , Fragmentos de Péptidos/genética , Secuencia de Aminoácidos , Colagenasas/química , Colagenasas/metabolismo , Escherichia coli/enzimología , Regulación Enzimológica de la Expresión Génica , Humanos , Metaloproteinasa 8 de la Matriz , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Reacción en Cadena de la PolimerasaRESUMEN
A23187-induced pleurisy in the mouse was demonstrated in this study. The protein leakage, leukocyte accumulation, LTB4 and PGE2 production in the pleural cavity of mice were increased by A23187 in a dose-dependent manner. At 7.5 nmole A23187 intrapleural injection, the protein level peaked at 0.5-2 h, PMN leukocytes accumulation peaked at 3-4 h, and LTB4 and PGE2 production peaked at 0.5-1 h. In this in vivo model we investigated the anti-inflammatory effect of norathyriol, isolated from Tripterospermum lanceolatum. A23187-induced protein leakage was reduced by norathyriol (ID50 was about 30.6 mg/kg i.p.), indomethacin and BW755C. A23187-induced PMN leukocytes accumulation was suppressed by norathyriol (ID50 was about 16.8 mg/kg, i.p.) and BW755C, while enhanced by indomethacin. Like BW755C, norathyriol reduced both LTB4 and PGE2 production (ID50 was about 18.6 and 29.1 mg/kg i.p., respectively), while indomethacin reduced PGE2 but not LTB4 generation. We also demonstrated the analgesic effect of norathyriol on the acetic acid-induced writhing response. Acetic acid-induced writhing response was depressed by norathyriol (ID50 was about 27.9 mg/kg i.p.), indomethacin and ibuprofen. These results suggest that norathyriol, like BW755C, might be a dual, yet weak, cyclooxygenase and lipoxygenase pathway blocker. The inhibitory effect of norathyriol on the A23187-induced pleurisy and acetic acid-induced writhing response in mice is proposed to be dependent on the reduction of eicosanoids mediators formation in the inflammatory site.