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51.
52.
Differential neuronal survival in the avian ciliary ganglion after chronic acetylcholine receptor blockade 总被引:2,自引:0,他引:2
We have described in the preceding 2 papers the development of the pharmacological and contractile properties of all targets of the ciliary ganglion: the iris and ciliary body (Pilar et al., 1987), and the choroidal coat (Meriney and Pilar, 1987). In this paper, we examine the chronic effects of ACh receptor (AChR) blockade on ciliary ganglion neuron survival. Nicotinic or muscarinic AChR blockers were administered daily to developing chicken embryos during the normal neuronal death period in the ciliary ganglion. The effects of the blockers on ganglionic and neuromuscular transmission were assessed, and neuronal survival was assayed by counting both the total number of ganglion neurons and the selectively HRP-labeled ciliary neurons after the normal neuronal death period. Blockade of ganglionic transmission decreases survival in both populations of neurons. Blockade of neuromuscular muscular transmission increases survival in the ciliary population, which innervates the striated iris and ciliary body muscle. In contrast, blockade of synaptic activity has various influences on the survival of the choroid population, which innervates the smooth muscle of the choroid coat. Smooth muscle muscarinic receptor blockade with atropine does not influence survival. At higher doses (which block ganglionic transmission), atropine decreases choroid survival. Survival of the choroid population is increased by nicotinic blockade with 75 micrograms alpha bungarotoxin (alpha BTX), but decreased by 12.5 micrograms alpha BTX. Two main conclusions arise from these studies. Activation of postsynaptic AChRs in both the ganglion and the periphery are important in the regulation of neuronal survival. These effects usually occur in opposite directions: Blockade of ganglionic transmission decreases neuronal survival, while paralysis of neuromuscular transmission increases neuronal survival. This embodies the "balance" hypothesis (Cunningham, 1982) for neuronal survival, which states that motoneurons must balance afferent and target interactions during a critical period after synapses are formed in both regions. The present observations support this hypothesis. However, although both ciliary and choroid neurons have been shown to depend on the presence of the periphery for survival, target muscle paralysis via AChR blockade rescues the ciliary neurons but does not influence survival in the choroid population. Target-dependent regulation of choroid neuron survival during the normal neuronal death period is clearly different from the regulation of ciliary neuron survival. 相似文献
53.
Rosa M. García-García María Arias-lvarez Pilar Milln María Rodríguez Ana Snchez-Rodríguez Pedro L. Lorenzo Pilar G. Rebollar 《Nutrients》2021,13(2)
Nutritional status during gestation can influence mother and offspring metabolism. Undernutrition in pregnancy affects women in both western and developing countries, and it is associated with a high prevalence of chronic diseases in later life. The present work was conducted in the rabbit model, as a longitudinal study, to examine the effect of food restriction during early and mid-gestation, and re-feeding ad libitum until the end of pregnancy on metabolic status and body reserves of mother and, its association with development and metabolism of fetuses and female offspring to the juvenile stage. Little changes in live body weight (LBW), compensatory feed intake, similar body reserves, and metabolism were observed in dams. Placenta biometry and efficiency were slightly affected, but fetal BW and phenotype were not modified. However, hyperinsulinemia, insulin resistance, and hypertriglyceridemia were demonstrated in pre-term fetuses. In the juvenile period, these changes were not evidenced, and a similar pattern of growth and serum metabolic parameters in offspring of food-restricted mothers were found, except in serum aminotransferases levels, which increased. These were associated with higher liver fibrosis. Maternal food restriction in the early and mid-pregnancy followed by re-feeding in our rabbit model established a compensatory energy status in dams and alleviated potential long-term consequences in growth and metabolism in the offspring, even if fetal metabolism was altered. 相似文献
54.
Alfredo García-Layana Sergio Recalde Maria Hernandez Maximino J. Abraldes Joo Nascimento Emiliano Hernndez-Galilea Begoa Olmedilla-Alonso Jose Juan Escobar-Barranco Miguel Angel Zapata Rufino Silva Mariana Caballero Arredondo María Carmen Lopez-Sabater Silvia Mendez-Martínez Nieves Pardias-Barn Pilar Calvo Patricia Fernndez-Robredo 《Nutrients》2021,13(4)
The purpose of this study is evaluate the efficacy and safety of medicinal products containing the original Age-Related Eye Disease group (AREDS) formulation at doses approved in Europe (EU, control group; n = 59) with a product that adds DHA, lutein, zeaxanthin, resveratrol and hydroxytyrosol to the formula (intervention group; n = 50). This was a multicenter, randomized, observer-blinded trial conducted in patients aged 50 years or older diagnosed with unilateral exudative Age related Macular Degeneration AMD. At month 12, the intervention did not have a significant differential effect on visual acuity compared with the control group, with an estimated treatment difference in Early Treatment Diabetic Retinopathy Study (ETDRS) of −1.63 (95% CI −0.83 to 4.09; p = 0.192). The intervention exhibited a significant and, in most cases, relevant effect in terms of a reduction in some inflammatory cytokines and a greater improvement in the fatty acid profile and serum lutein and zeaxantin concentration. In patients with unilateral wet AMD, the addition of lutein, zeaxanthin, resveratrol, hydroxytyrosol and DHA to the AREDS EU recommended doses in the short-term did not have a differential effect on visual acuity compared to a standard AREDS EU formula but, in addition to improving the fatty acid profile and increasing carotenoid serum levels, may provide a beneficial effect in improving the proinflammatory and proangiogenic profile of patients with AMD. 相似文献
55.
Lorena Villalba-Heredia Cristina Comeras-Chueca Alejandro Gonzlez-Agüero Daniel Domingo-del-Val Pilar Calmarza Germn Vicente-Rodríguez Jos A. Casajús ngel Matute-Llorente 《Nutrients》2021,13(5)
Childhood obesity has become a major global health problem. Vitamin D deficiency and poor cardiorespiratory fitness are highly prevalent in children with overweight or obesity, but little is known about their relationships. In this study, we aimed to analyze the relationship between serum 25-hydroxyvitamin D (25(OH)D) and cardiorespiratory fitness parameters in prepubertal obese and overweight children. A cross-sectional design with a sample of 57 prepubertal children, aged 9–11 years, with overweight or obesity was used. The fasting concentration of 25(OH)D was analyzed with a chemiluminescent microparticle immunoassay. Fat and lean body masses were determined by using DXA. Maximal oxygen uptake (VO2max) was measured with the maximal treadmill test. A total of 68.4% of the sample had sufficient levels of 25(OH)D. As expected, their cardiorespiratory fitness was poor compared with that of normal-weight children, but 60% of the group exceeded the median obesity-specific reference values. No differences were found between the sexes for relative VO2max or 25(OH)D levels. Moreover, no correlations were found between 25(OH)D and body composition or cardiorespiratory parameters for sex or vitamin D groups. Vitamin D status seems not to be directly related to body composition or cardiorespiratory fitness in prepubertal overweight or obese children. 相似文献
56.
57.
Sara Ares-Blanco María Pilar Astier-Peña Raquel Gómez-Bravo María Fernández-García José Miguel Bueno-Ortiz 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2021,53(10):102132
This article describes the management of human resource and the vaccination strategies in primary care in twelve European countries in relation to the COVID-19 pandemic. All the countries have found solutions to increase their workforce in primary care. Other healthcare professionals were incorporated to support family doctors assuming their tasks, under their supervision and coordination. The European Commission had a crucial role in the production, purchase and distribution of the vaccines. The engagement of primary care in the vaccination campaign has had an unequal participation in the different countries, although the greatest burden has been managed from the government's public health departments. 相似文献
58.
M. Pilar Honrubia M. Paz Herráez Rafael Alvarez 《Archives of environmental contamination and toxicology》1993,25(2):184-191
Embryos of Rana perezi were kept under laboratory conditions and treated with carbamate ZZ-Aphox® at chronic doses of 0.02 and 0.14 for 9 weeks. Both the histological study and the analysis of mortality show a direct relationship between the dosage and the effects of the pesticide. The histological study of the survivors over 56 days show damages in gills, liver, gall-bladder, heart, and notochord. Damages on the epithelia of gills (on their distal portion) and gall-bladder recover over a few days, whereas those provoked on the compacting of the hepatic parenchyma and the hepatocytes, the auricle and the perinotochordal collagenic fibers alter their structure in a lasting way. Potentials of such alterations are discussed, with special reference to the possible interference of the pesticide on the successful synthesis of the supporting connective sheaths. 相似文献
59.
Summary A seroepidemiological study was carried out in order to determine the prevalence of markers of viral hepatitis infection in employees of five health-care companies and their cohabiting family members. Each participating family unit was required to fill out a questionnaire, in which, among other data, the employee was requested to indicate his or her job category. Markers of hepatitis B infection (anti-HBs, anti-HBc or HBsAg) were observed in 11.7% (58/497) of all subjects. When employees and family members were analysed according to the employee's job category, significant differences were found between staff (3%) and administrative personnel (13.3%; p<0.01) or factory workers (16.9%; p<0.01). Of 489 individuals tested for the presence of anti-HAV and anti- HCV, 59.1% and 0.6% respectively, were positive. There was a correlation between the prevalence of anti-HAV and age; a large proportion of the subjects under the age of 30 years had no evidence of prior HAV infection.
Prävalenz der Hepatitis B, A und C in einer gesunden spanischen Bevölkerungsgruppe. Aktuelle seroepidemiologische Studie
Zusammenfassung Um die Prävalenz von Virus-Hepatitis-Markern zu ermitteln, wurde eine seroepidemiologische Studie durchgeführt, in die Beschäftigte von fünf pharmazeutischen Firmen und Familienmitglieder der Wohngemeinschaft aufgenommen wurden. Fragebogen, die alle teilnehmenden Familien auszufüllen hatten, enthielten unter anderem Daten zur Berufsbezeichnung. 58 von 497 untersuchten Seren (11,7%) wiesen Marker einer Hepatitis B Virus-Infektion auf (anti-HBs, anti-HBc oder HBsAg). Nach Berufskategorie aufgeschlüsselt, fanden sich zwischen Beschäftigten und Familienmitgliedern signifikante Unterschiede: Personen, die zum Staff gehörten, waren in 3% der Fälle positiv, Verwaltungspersonal in 13,3% (p<0,01), Fabrikarbeiter in 16,9% (p<0,01). Von den 489 auf anti- HAV getesteten Personen waren 59,1 % positiv, anti-HCV-Antikörper wiesen in derselben Gruppe 0,6% der Getesteten auf. Die Prävalenz von anti-HAV zeigte eine Altersabhängigkeit; ein großer Anteil der unter 30jährigen hatte keine Marker für eine durchgemachte HAV-Infektion.相似文献
60.
Francisco Javier Torres Gómez Pilar Jurado Escámez Francisco Javier Torres Olivera 《Clinical & translational oncology》2004,6(8):493-495
Hibernoma is a rare benign tumor arising in brown fat arising in young adults with similar incidence in both sexes. They are generally subcutaneous reaching in some instances a considerable size. The interscapular region, shoulders, head and neck are the main locations, but rare cases have been described in a wide variety of sites. Histologically three types of cells mixed in different proportions corresponding to the stages of maduration of the fatty cells. They are benign tumors with not recurrence after excision. We report a pleural hibernoma, a location not reported previously in the literature. 相似文献