RESUMEN
BACKGROUND: Cervical mucus is a heterogeneous mixture of water, ions and mucins that form a hydrophilic polymer gel. Mucins, the main components of mucus, are condensed inside secretory granules and swell to become a hydrogel after exocytosis. Using human cervical secretory cell primary cultures, the effect of [Ca(2+)] and [H(+)] on the swelling velocity of mucin granules was investigated in vitro. METHODS AND RESULTS: Immunocytochemistry demonstrated that estrogen and progesterone receptors were expressed in cultured secretory cells along with mucins type 1, 4, 5AC and 5B. Exocytosis of secretory cells, recorded by videomicroscopy, showed that during swelling, the radius of the secretory granule matrix followed first-order kinetics. An increase in extracellular [Ca(2+)] from 1 to 4 mmol/l or a reduction in pH from 7.4 to 6.5 was seen to produce a significant decrease in the velocity of swelling of the secretory granule matrix. CONCLUSIONS: The inverse relationship observed between the diffusion of the granular matrix and the extracellular [Ca(2+)] or [H(+)] suggested that changes in cation concentration might drastically affect the swelling characteristics of mucins and provide a control mechanism for the observed viscoelastic properties of mucus.
Asunto(s)
Ácidos/metabolismo , Calcio/metabolismo , Cuello del Útero/metabolismo , Espacio Extracelular/metabolismo , Mucinas/fisiología , Células Cultivadas , Cuello del Útero/citología , Células Epiteliales/metabolismo , Femenino , Humanos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Vesículas Secretoras/fisiología , Factores de TiempoRESUMEN
A cross-national study of hip fracture incidence was carried out in five geographic areas--Beijing, China; Budapest, Hungary; Hong Kong; Porto Alegre, Brazil; and Reykjavik, Iceland--during the years 1990-1992. Cases of hip fracture among women and men of age 20 years and older were identified using hospital discharge data in conjunction with medical records, operating room logs, and radiology logs. Estimated incidence rates varied widely, with Beijing reporting the lowest rates (age-adjusted rate per 100,000 population for men 20 years and older = 45.4; women = 39.6) and Reykjavik the highest rates (man = 141.3; women = 274.1). Rates were higher for women than for men in every area except Beijing. In every area except Budapest, review of the operating room or radiology logs identified additional cases that were not reported in the discharge list, increasing the estimated number of hip fractures by 11% to 62%, depending on the area. Review of medical records identified miscoding of hip fractures (ICD 9820) as 'shaft of femur and other femur fractures' (ICD 9821) in the discharge lists of every area except Budapest, increasing the estimated number of hip fractures by 1% to 30%. The final estimates of hip fracture incidence taking into account all investigated sources of undercount and overcount ranged from 15% lower to 89% higher than an estimate based on the discharge diagnoses alone. Although these results indicate substantial limitations in relying on hospital discharge data alone to estimate hip fracture incidence rates, the extent of errors found in the discharge lists is smaller than the large international variation found here and previously reported in incidence rates. The findings support the conclusion that the differences reported among countries mainly reflect genuine variation in the hip fracture incidence rates.
Asunto(s)
Fracturas de Cadera/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , China/epidemiología , Femenino , Hong Kong/epidemiología , Humanos , Hungría/epidemiología , Incidencia , Masculino , Registros Médicos , Persona de Mediana Edad , Distribución por SexoRESUMEN
OBJECTIVE: To study patients with atrioventricular septal defect to determine the pathognomonic morphological features of the lesion and the relation between the septal structures and the atrioventricular junction. Setting : Tertiary level paediatric cardiology centre. METHODS: Cross sectional echocardiograms from 60 patients were reviewed using qualitative and quantitative analysis. The unifying feature was the presence of a common atrioventricular junction. The overall dimensions of the septal defect were determined and related to the plane of the common junction; the extent of both the atrial and the ventricular septal components was then measured according to the site of closure of the bridging leaflets. RESULTS: In 48 cases, the common junction was guarded by a common valvar orifice, but in 12 cases there were separate right and left valvar orifices. Irrespective of the valvar morphology, no significant difference was found between the groups in terms of the dimensions of the atrial and ventricular septal components. In all patients, the hole permitting shunting at atrial level extended below the plane of the atrioventricular junction, with a variable position of the leading edge of the atrial septum itself. CONCLUSIONS: The atrioventricular junction is a common structure irrespective of valvar morphology. In spite of the presence of unequivocal shunting at atrial level, the atrial septum is usually a well formed structure, even extending in some below the level of the common atrioventricular junction.
Asunto(s)
Nodo Atrioventricular/diagnóstico por imagen , Defectos de los Tabiques Cardíacos/diagnóstico por imagen , Tabiques Cardíacos/diagnóstico por imagen , Adolescente , Adulto , Niño , Preescolar , Ecocardiografía , Femenino , Defectos de los Tabiques Cardíacos/fisiopatología , Humanos , Lactante , Recién Nacido , Masculino , Estudios RetrospectivosRESUMEN
A comparison of hip fracture rates among nine countries (Canada, Chile, Finland, Hong Kong, Scotland, Sweden, Switzerland, the United States and Venezuela) was made using national hospital discharge data for the same time interval. The rates increased by age and were higher for females than males in all nine countries. When based on overall discharge rates, the incidence of hip fracture appeared high in three European countries (Finland, Scotland and Sweden) relative to the other countries. However, when transfer cases were removed and adjustments made for differences in case definition, the risk of hip fracture for both men and women was much similar among the four European and two North American countries, but higher than in Hong Kong. Rates of fracture were lowest in Venezuela and Chile, varying from three to 11 times less than for residents of the other seven countries. Although there are limitations in using hospital discharge data as a measure of incidence, the wide variation in the risk of hip fracture across the nine countries appears real but differences between North American and north European countries may not be as great as previously reported. Such cross-national comparisons may help clarify different etiologic hypotheses.
Asunto(s)
Fracturas de Cadera/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Europa (Continente)/epidemiología , Femenino , Hong Kong/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , América del Norte/epidemiología , Alta del Paciente/estadística & datos numéricos , Factores Sexuales , América del Sur/epidemiologíaRESUMEN
The report describes the morphologic features of 102 specimens with hypoplasia of the chambers of the left heart, all with either a concordant atrioventricular connection (66 cases) or absence of the left atrioventricular connection, the right atrium being connected to a dominant right ventricle (36 cases). Either the aorta was connected to the left ventricle, having a patent valve in 23 cases and an imperforate valve in 5, or else the aortic trunk was atretic (74 cases). It was not possible to determine with certainty the ventricular origin of the aorta when its trunk was atretic, but in all hearts but 1 it seemed to be connected to the left ventricle. The atrial septum was intact in 11 hearts and grossly restrictive in a further 8. Deviation of the atrial septum relative to the infolded atrial roof (septum secundum) was seen in 32 specimens. The ventricular septum was intact in 88 hearts. The length of the left ventricle compared to the right was greatest in the 14 hearts with a ventricular septal defect. The left ventricular length was also significantly greater in hearts with a patent aortic valve. The state of the atrial septum, in contrast, bore no relationship to the dimensions of the left ventricle. Aortic coarctation was found in 44 of the hearts, and in all but 2 the shelf lesion was preductal in location. Coarctation was significantly more frequent in those hearts in which the ascending aorta was less than 3 mm in diameter. The anatomic findings are discussed in relation to recent advances in the surgical palliation of these malformations.
Asunto(s)
Cardiopatías Congénitas/patología , Coartación Aórtica/patología , Válvula Aórtica/anomalías , Estenosis de la Válvula Aórtica/congénito , Estenosis de la Válvula Aórtica/patología , Atrios Cardíacos/anomalías , Ventrículos Cardíacos/anomalías , Humanos , Recién Nacido , SíndromeRESUMEN
We report a case of pulmonary atresia with ventricular septal defect and absent pulmonary trunk. The sources of pulmonary blood supply were the arterial duct and systemic pulmonary collateral arteries. The left lung received blood from both sources which is very rare. One of the systemic pulmonary collateral arteries arose from the right coronary artery in an unusual fashion.
Asunto(s)
Anomalías de los Vasos Coronarios/patología , Defectos del Tabique Interventricular/patología , Pulmón/irrigación sanguínea , Arteria Pulmonar/anomalías , Válvula Pulmonar/anomalías , Circulación Colateral , Humanos , Recién Nacido , MasculinoAsunto(s)
Servicios de Salud Materna , Enfermería Pediátrica , Niño , Femenino , Humanos , Embarazo , InvestigaciónRESUMEN
There were 177 pairs of twins reviewed. The incidence of twin pregnancy was 1:112.2 deliveries in a population consisting of 76.8 per cent Mexican-Americans. The incidence of breech, cesarean section, and assisted deliveries was higher in twins than singleton deliveries, and the incidence was higher in twin 2 than twin 1. Mortality rates, fetal and neonatal, were lower than those previously reported. Neonatal findings and complications include low Apgar scores, small-for-dates infants, hyaline membrane disease, hypoglycemia, hypocalcemia, hyperbilirubinemia, and congenital malformation. The increased incidence of deaths and morbidity in twin pregnancy, as compared to singleton pregnancy, was attributed to prematurity, and to complications and diseases pertaining to prematurity, rather than to twinning per se.