Miguel Angel Sala

Histometric study of socket healing after tooth extraction in rats treated with diclofenac

The purpose of the present study was to investigate if diclofenac administration interferes with the time course of alveolar wound healing in rats. Forty-two Wistar rats were used, 21 rats received 10 mg/kg/day of diclofenac one day before and 4 days after extraction of the right maxillary incisors and 21 rats received saline. The animals were sacrificed 7, 14 and 21 days after tooth extraction. Progressive new bone formation and a decrease in the volume fraction of blood clot and connective tissue from 1 to 3 weeks after tooth extraction was quantified using the histometric point-counting method. Diclofenac treatment caused a significant delay in new bone formation in association with an impairment of blood clot remission/organization.

Action of trivalent chromium on rat liver structure. Histometric and haematological studies

El cromo trivalente (Cr3+) es un nutriente esencial involucrado en la regulacion del metabolismo de carbohidratos, lipidos y proteinas, a traves de un estimulo a la accion de la insulina. El objetivo del presente trabajo fue caracterizar histopatologicamente e histometricamente las alteraciones hepaticas de ratas Wistar hembras, provocadas por la administracion de cromo III en agua potable. Ratas adultas recibieron racion y agua potable ad libitum, conteniendo 300 o 500 mg/l de cromo III, durante 4 meses. Los animales control recibieron solo agua y racion. Todos los animales fueron sacrificados con dosis letal de anestesico. Muestras de higado, fijadas en formol al 10% por 24 h, fueron cortadas a 6 µm y tenidas con hematoxilina y eosina o PAS. Ademas del examen histopatologico, fueron usadas tecnicas histometricas. La sangue fue recolectada y procesada para estudio hematologico. El analisis histopatologico revelo, en la zonas periportal, intermediaria y pericentrolobular, celulas parenquimatosas con grados variables de vacuolizacion. Muchos hepatocitos mostraban degeneracion baloniforme con nucleos lisados. La vena centrolobular estaba dilatada y congestionada. Se observaron sinusoides dilatados conteniendo eritrocitos. La zona porta mostro fibrosis y proliferacion de ductos biliares con pequenas celulas. La histometria mostro aumento de los volumenes de citoplasma y celular, y valores menores para el numero de hepatocitos por mm3. Linfopenia fue observada en los animales tratados con 500 mg/l de Cr3+. Estos resultados indican que el cromo III tiene una participacion directa en las alteraciones de las estructuras hepaticas

Efectos del Albendazol en el hígado de feto de rata. Estudios morfológico y morfométrico

El objetivo del presente trabajo fue caracterizar morfologica, morfometrica y estereologicamente las alteraciones causadas por la administracion de albendazol en ratas prenadas en el higado de los fetos. Fueron usadas ratas Wistar, que recibieron entre los dias 9 y 11 de la prenez, una dosis diaria de 5 mg/kg de peso de albendazol. Las ratas control recibieron volumen semejante de suero fisiologico en los mismos dias. Al 20 dia, las ratas fueron sacrificadas por inhalacion de eter, siendo retirados los fetos e inmediatamente fijados en alfac por 24 h. Los fetos, uteros y placentas, luego de fijados, fueron secados en papel de filtro y pesados en balanza de precision, siendo medidos los cordones umbilicales con nonio. Los cuerpos de los fetos fueron seccionados longitudinalmente e incluidos en parafina. Los cortes seriados de 6 µm de espesor, fueron tenidos con hematoxilina y eosina. Ademas del examen histopatologico, fueron utilizadas tecnicas histometricas. Los resultados obtenidos, en las condiciones experimentales, sugieren que la exposicion prenatal al albendazol actua directamente en la embriogenesis, causando malformaciones como agenesia del rabo y fetos hidropicos. En los fetos sin malformaciones, la droga causo retardo del desarrollo fetal, caracterizado por reduccion de peso corporal, peso de la placenta y longitud del cordon umbilical, asi como alteraciones estructurales hepaticas, reflejadas en hepatocitos menores con nucleos menores y citoplasma mas escaso y aumento de la densidad numerica. Los megacariocitos eran mayores, con nucleos lobulados grandes, con mayor volumen relativo. Los sinusoides ocuparon un volumen relativo semejante en los fetos de los dos grupos estudiados. Los fetos tratados, ademas de las malformaciones, mostraron aspectos que sugieren inmadurez al ser comparados con los controles

Efecto de la infección aguda por diferentes cepas de Trypanosoma cruzi sobre el crecimiento intrauterino de fetos de ratón

old, were i.p. inoculated with 2 x 10 5 trypomastigotes blood stream of T. cruzi (Colombian, Y, Bolivia or RC strains). The results allow to conclude that the T. cruzi infection affect the intrauterine growth of the mouse fetus, with reduction of both weight and length, umbilical cord length, body weight to placenta weight ratio and body weight to umbilical cord length ratio. T. cruzi strains showed different behavior. In general, the less prejudicial to the fetal growth was the RC strain, whereas the most prejudicial were the Bolivia and Y strains. The parasitemic curves of these strains show the most rapid growth, reaching the peak at the 5th and 7th day, respectively. As inoculation was made to agree the last pregnancy day with the parasitemic peak, the infected animals had the most rapid infection with elevated parasitemy, without possibility of maternal adaptation.

Attitudes of dental students and dental professionals caring for HIV-positive patients in São Paulo, Brazil.

Sao Paulo has a high incidence of AIDS. However many dentists are concerned about providing care for patients with AIDS/HIV. The reluctance of dentists to care for these patients is a matter of concern mostly because they are the health care providers who could easily detect the first signs and also observe the progression of the HIV infection. We sought to address the deficiencies in our community regarding the acceptance of HIV-infected patients. A self-administered survey questionnaire was given to graduate dental students (professors postgraduate students and fellows) and undergraduates working in the clinics of a dental school in Sao Paulo Brazil. All participants were informed that the survey participation was voluntary and confidential. The questionnaire consisted of questions focusing on knowledge about and attitudes toward AIDS/HIV. (excerpt)

Does l-arginine availability during the early pregnancy alters the immune response of Trypanosoma cruzi infected and pregnant Wistar rats?

Chagas disease induces a strong immune response and L-arginine is an essential amino acid which plays an important role in homeostasis of the immune system. The aims of this study were to evaluate parasitemia, corticosterone levels, production of nitric oxide (NO), fetal morphological measurements, and histology of heart and placenta. Twenty pregnant Wistar rats (180-220 g) were grouped in: pregnant control (PC), pregnant control and L-arginine supplied (PCA), pregnant infected (PI), pregnant infected and L-arginine supplied (PIA). Females were infected with 1×10(5) trypomastigotes of the Y strain (3rd day of pregnancy). Animals were supplied with 21 mg of L-arginine/kg/day during 14 days. PIA showed significant decreased levels of corticosterone and parasitemia. For control groups, any alteration in NO production was found with L-arginine supplementation; for PIA, enhanced nitrite concentrations were observed as compared to PI. Weights and lengths of fetuses were higher in L-arginine treated and infected pregnant rats as compared to untreated ones. Placental weight from the PIA group was significantly increased when compared to PI. In L-arginine treated animals, cardiac tissue showed reduced amastigote burdens. PIA and PI displayed similar placental parasitism. Based on these results, L-arginine supplementation may be potentially useful for the protection against Trypanosoma cruzi during pregnancy.

The carcinogenic potential of cadmium in the palatal and gingival epithelium of rats: a morphologic and morphometric analysis

Cadmium (Cd) is a heavy metal that exerts a variety of toxic effects, chronic and acute, in exposed organisms. The aim of this study was to investigate the carcinogenic potential of Cd in the palatal and gingival epithelium of Wistar rats. Two groups of animals were studied: group 1 consisted of 5 rats exposed to cadmium chloride (CdCl2) in drinking water (300 mg/L) for 6 months; group 2 also consisted of 5 rats placed in the same conditions as those of group 1, but kept free of Cd for 6 additional months. Two other groups (C1 and C2) with the same number of animals, but not exposed to CdCl2, were used as a control for groups 1 and 2, respectively. All animals were weighed before and after the experimental period. After animals being killed, tissues of interest were fixed in solution of 10% formalin, processed by standard histologic techniques, stained with HE, and analyzed under light microscopy using karyometric and stereologic parameters. Loss of body weight, atrophy of the gingiva and soft-palate epithelium were the principal findings of this study, and verified only in the group 1 (p < 0.05). In conclusion, at the concentration tested, Cd presented no carcinogenic effect on the oral tissues within the experimental time period.

Effects of cigarette smoke on the Meckel's cartilage of rat fetus : Morphologic, morphometric and stereologic study

The purpose of this study was to investigate the effects of cigarette smoke on the development of the embryo mandible (Meckels) cartilage in rat fetuses. When inhaled by female Wistar rats between the 9th and the 12th day of pregnancy, cigarette smoke (5 cigarettes a day) caused intrauterine growth retardation, providing smaller fetuses and placentas. In fetuses from the experimental group, the histopathologic examination revealed a poorly developed Meckels cartilage with smaller chondroblasts showing a scanty cytoplasm with spherical and paler central nuclei, as well as more abundant cartilage matrix. Morphometric analysis revealed that Meckels cartilage lacunae were smaller in the fetuses from the experimental group, although not showing any remarkable alteration in shape. The results suggested that inhalation of cigarette smoke by pregnant rats during the organogenic period induced growth retardation and delayed cellular differentiation in rat fetal Meckels cartilage.

Estudio Morfológico e Histoquímico de las Glándulas Cefálicas de Bothrops alternatus (Ophidia, Viperidae)

El objetivo del presente trabajo fue estudiar la histologia de las glandulas cefalicas de la vibora de la cruz (Bothrops alternatus), identificar los tipos celulares y caracterizar histoquimicamente el producto de secrecion. Con esta finalidad fueron usados ejemplares machos adultos de B. alternatus. Despues del sacrificio, las glandulas cefalicas fueron fijadas en formol neutro al 10% e incluidas en parafina. Los cortes, de 6 µm de espesor, fueron tenidos con hematoxilina y eosina, tricromico de Masson y con tecnicas histoquimicas para identificacion de mucopolisacaridos y proteinas. Los resultados histologicos demostraron que las glandulas linguales, de veneno y accesorias son de tipo tubular, las glandulas labiales y premaxilar son tubuloacinares y la glandula de Harder es tubuloacinar compuesta. Las celulas mucosas de los adenomeros y conductos secretores de las glandulas linguales, labiales y premaxilar, asi como las celulas de los conductos de la glandula de Harder, secretan sulfosialomucinas y mucopolisacaridos neutros. Las celulas mucoserosas de las glandulas linguales, labiales y premaxilar sintetizan mucopolisacaridos neutros, acido sialico y radicales tirosina, cistina, cisteina, arginina y triptofano. Las celulas seromucosas de las glandulas de veneno, accesorias y de Harder producen polisacaridos neutros y radicales cistina, cisteina y triptofano, mientras que la glandula de Harder tambien sintetiza tirosina.

Characteristics of primary care processes for the treatment of faecal incontinence in an urban area.

Aim  In this study, we investigated the adequacy of the healthcare response systems to detect and treat faecal incontinence in patients in the primary care areas (PCAs) in a core urban area of Barcelona.