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Biomedical subjects

C Retamal

Publications and source records attributed to C Retamal.

At least 19 recordsLinked to original sources
PubMed2001

[Indoor air pollution in a zone of extreme poverty of La Pintana, Santiago-Chile].

BACKGROUND: Indoor pollution can be an important risk factor for human health, considering that people spend more than 60% of their time in their houses. AIM: To investigate indoor pollution in a zone of extreme poverty in Metropolitan Santiago. MATERIAL AND METHODS: During 24 h, carbon monoxide (CO), sulfur dioxide (SO2), respirable particulate matter (PM10), polycyclic aromatic hydrocarbons absorbed in PM5, temperature and humidity, were measured in the interior of 24 houses in a La Pintana, Santiago. RESULTS: The higher pollutant concentrations were observed during hours when heating was used, in houses that used coal (mean PM10 250 micrograms/m3, CO 42 ppm, SO2 192 pph) or firewood (mean PM10 489 micrograms/m3, CO 57 ppm, SO2 295 pph). In all houses, polycyclic aromatic hydrocarbons were detected and they came from the interior of the house and not from external filtered air. Coal, firewood and cigarette smoke were important sources of carcinogenic and kerosene and gas were sources of non carcinogenic polycyclic aromatic hydrocarbons. CONCLUSIONS: In the houses studied, the population was exposed to an accumulation of highly toxic pollutants, caused by a lack of ventilation. A high relative humidity also contributed to the growth of biological pollutants.

Adolescent↗
PubMed2000

[Echinococcosis/hydatidosis in the VII Region of Chile: diagnosis and educational intervention].

This study was designed to embrace three areas: a) serologic and radiologic diagnosis and surgical treatment of hydatidosis in an asymptomatic human population, b) animal diagnosis and the treatment of dogs, and c) evaluation of extent of knowledge and performance of educational interventions among rural families and health, livestock, and education professionals and technicians, in order to help control the disease transmission cycle. Indirect hemagglutination and ELISA tests were performed on 5,556 apparently healthy people. Of these, 42 (0.8%) had positive results on both tests, for a seroprevalence of 754.6 per 100,000. These 42 subjects were scheduled for liver ultrasonography and a chest x-ray; of the 26 who complied, 16 showed images compatible with a hydatid cyst. Those 16 cases were sent to the hospital for surgery. In 9 of the cases the diagnosis was confirmed surgically, for a prevalence of 161.7 per 100,000. Arecoline hydrobromide was administered as a laxative to 2,358 dogs to detect the strobilar form of Echinococcus granulosus, and positive results were found in 11% of the dogs. Official data for slaughterhouses indicated the presence of hydatid cysts in 13% of the cattle, 4.4% of the sleep, and 4.2% of the pigs slaughtered in the region. The educational program included an evaluation of the extent of knowledge by surveying heads of household; an educational intervention among families through an informal active participatory process using educational games, in which 1,082 families participated; and an educational intervention with professionals and technicians using distance and in-person approaches. To evaluate the program, the results of knowledge tests before and after educational interventions with 200 families (cases) were compared with those from 95 families who did not participate (controls). Of the 1,423 heads of household initially surveyed about their knowledge of echinococcosis/hydatidosis, 783 of them (55%) said they knew nothing about the infection. It was found that the participatory educational games were well adapted to the lifestyle of people from rural areas and made change possible. Training was provided to 276 health professionals, 201 technical assistants, and 453 rural teachers. The program reached 100% of the staff members of the area's rural primary health care services.

Animals↗
PubMed2000

Cytochemical and electrophoretic study of the stallion epididymal glycoproteins.

It has been suggested that proteins produced in specific regions of the epididymis, mostly androgen dependent glycoproteins, are involved in the sperm maturation process. In the present work, the glycoconjugated distribution pattern and the electrophoretic characteristics of the stallion epididymal proteins were examined using lectin probes. The identification in the luminal fluid of some new proteins, probably synthesized and secreted by the epididymis, is an important initial step to investigate their interaction with the stallion sperm membrane. The binding of FITC-lectins (ConA, WGA, LPA, UEA, RCA, HPA) confirmed the presence of macromolecules containing carbohydrate residues in the epithelial cells with a distribution and relative density that was dependent on the epididymal region analyzed. The epithelium displayed affinity for more than one lectin, indicating diversity in the exposed sugar residues. The electrophoretic pattern of proteins obtained from ductus efferentes, corpus and cauda epididymis differed not only from those of the homologous blood serum, but also among the different epididymal regions. The most prominent bands correspond to 66, 55, 45 and 14 kDa proteins, present in different relative concentrations, in the three analyzed regions. A major band of 36 kDa was observed in the cauda epididymis region. The relative concentrations of protein bands of Mw 45, 36, 32, 20 and 18 kDa were significantly increased towards the distal regions of the ductus. The proteins of Mw 66, 55 and 14 kDa showed a relative higher concentration in the efferent ducts, decreasing to 25-30% in the cauda epididymal regions. The Mw 70, 66, 55, 45, 36, 32, 29, 23, 21, 18 and 14 kDa protein bands gave positive PAS reaction indicating that it corresponds to glycoproteins. Mannose residues were detected in the 70, 66, 55, 45, 36 and 32 kDa proteins. WGA-FITC binds to protein bands of Mw 70, 55, 45, 36, 32, 29, 25 and 24 kDa, suggesting the presence of N-linked glycoproteins. However, based on the resistance to the neuraminidase treatment, we suggest that the stallion epididymis contains both O- and N-glycoconjugates, probably in the N-acetyl O-diacetyl form. Although sperm maturation is an androgen-dependent process, no striking differences were detected in the SDS-PAGE obtained from animals in breeding and non-breeding seasons.

Animals↗
PubMed2000

Changes in the plasma membrane proteins of stallion spermatozoa during maturation in the epididymis.

The present paper reports modifications in the electrophoretic and cytochemical characteristics of mature and immature stallion spermatozoa. Some sperm surface glycoproteins (36, 32, 29, 21, 20, 18 kDa) detected in cauda epididymidis spermatozoa, were either absent or present in a very low relative concentration in immature sperm cells. A major 14 kDa protein band, observed in sperm extracts obtained from ductus efferentes, progressively decreased along the epididymal ductus. The nature and distribution of carbohydrate residues on the sperm membrane, during epididymal maturation, was also studied by use of lectin probes. Some protein bands bound concanavalin A while others, as the 36, 32 and 20 kDa proteins, exhibited higher affinity for WGA lectin. The distribution and relative density of mannose-, galactose-, N-acetylglucosamine-, N-acetylgalactosamine-, fucose- and sialic acid-containing macromolecules showed a characteristic pattern depending on the sperm membrane domain and on its origin. Some sperm surface domains displayed affinity for more than one lectin, indicating a diversity in their exposed carbohydrate residues, whereas others bound only one or no lectin. The passage of spermatozoa through the epididymidis was accompanied by changes in the accessibility or abundance of lectin ligands. Some lectins (UEA, WGA, LPA) gave stronger reaction in mature spermatozoa, while others (RCA, WFH, PNA) stained better immature spermatozoa. This remodeling of sperm surface molecules is probably a consequence of interactions between spermatozoa and the epididymal secretions, and may reflect addition or adsorption of new molecules, space configurations changes or biochemical modifications of pre-existing compounds. Our results suggest that the distribution and density of terminal oligosaccharidic residues on the sperm plasma membrane have species-specific characteristics. These post testicular developmental changes may be of significance in the overall understanding of the stallion fertility.

Animals↗
PubMed1997

Regional differentiation of the blood-epididymis barrier in stallion (Equus caballus).

The occurrence, localization and ultrastructural characteristics of a blood-tissue barrier throughout the stallion proximal seminal excurrent duct system were studied by the exclusion of electron-dense tracers and freeze-fracture techniques. Striking differences were observed in the distribution of lanthanum tracer and in the geometrical organization of the zonulae occludentes along the ductus efferentes, epididymides and vas deferens. The zonulae occludentes domain, the principal structural component of the blood-epididymis barrier, differed in permeability, width and strand numbers along the ductus. The flow of tracer was not impeded by the vascular endothelium, the peritubular myoid layer or other surface membrane specialization. The tight junctions of the ductuli efferentes are poorly developed but unlike those of rats, guinea pigs or man they are not associated with gap junctions. The result of the tracer experiments and the low number of tight junctional strands in the ductuli efferentes suggests that the barrier of the ductuli efferentes corresponds to the 'leaky type'. In the epididymis the zonulae occludentes are well developed throughout the duct. The greatest number of strands, especially in the cauda epididymidis regions, correlates well with a decreased junctional permeability in this area. Another evidence for the existence of the stallion blood-epididymis barrier are the differences in the proteins electrophoretic profiles between blood plasma as compared with the fluid inside the seminal ductus. This junctional complexes contribute to create a highly defined luminal fluid microenvironment that ensures the sperm maturation and survival.

Animals↗
PubMed1995

[Absent or reverse diastolic umbilical flow].

We show our experience in the diagnostic and management of 19 pregnancies with absent or reverse diastolic blood flow velocity (ARFV) in the umbilical artery. The presence of ARFV was a rare condition (2.2% of the high risk patients), and it was associated with a poor prognosis shown by the high percentage of fetuses SGD (small for gestational age) (63.2%), malformations and hydrops fetalis (26%) and asphyxiated fetuses, giving a final perinatal mortality rate of 36.8%. In 8 cases (42.1%) the termination or pregnancy was delayed for at least 48 hours, allowing in some cases the administration of corticosteroid. There were significant differences when comparing the groups of survivors and non survivors in relation to the gestational age at the moment of delivery (33.1 +/- 3.4 vs 28.6 +/- 3.8 weeks), malformations (8.3 vs 57.1%) and C-section (91.7 vs 42.9%). Finally, we conclude that the presence of ARFV in the umbilical artery is associated with a critical fetal condition and termination of pregnancy should be considered. In this decision the gestational age and fetal and maternal well being ought to be taken into account when choosing the best moment and route of delivery.

Adult↗
PubMed1995

[Evaluation of ELISA and counterimmunoelectrophoresis in diagnosis of human neurocysticercosis in Chile].

The aim of this work was to assess the diagnostic accuracy for neurocysticercosis, of ELISA and counterimmunoelectrophoresis techniques, in sera and cerebrospinal fluid. Two hundred eight serum samples (47 coming from patients with confirmed cysticercosis) and 87 cerebrospinal fluid samples (27 coming from patients with confirmed cysticercosis) were analyzed. A crude and standardized extract of swine muscle cysticercus cellulose was used as antigen. ELISA and counter immunoelectrophoresis had a 100% specificity in cerebrospinal fluid. In sera, counterimmunoelectrophoresis had a 94.1% specificity. In sera and cerebrospinal fluid, ELISA had a 85.1% sensitivity. Cross reactions were observed in sera of patients with confirmed hydatidosis. Thus, the high specificity of both techniques in cerebrospinal fluid is probably due to the low incidence of cerebral hydatidosis in Chile. It is concluded that for the diagnosis of neurocysticercosis, antibodies against cysticercus cellulosae must be sought paralelly in serum and cerebrospinal fluid using ELISA and counterimmunoelectrophoresis.

Adult↗
PubMed1993

[Prevalence of fascioliasis in humans, horses, pigs, and wild rabbits in 3 Chilean provinces].

This study sought to estimate for the first time the prevalence of fascioliasis among the rural population in the Chilean provinces of Curico, Talca, and Linares, while also determining the disease's prevalence among horses and wild rabbits in Curico and Talca and among pigs in Talca. From January 1986 to December 1990 a randomly selected sample of 5,861 persons in the three provinces was given intradermal, complement-fixation, double-diffusion, and immunoelectrophoresis tests to detect antibody to Fasciola hepatica. In addition, the ELISA test was used in Talca and Linares. Fecal specimens from horses and pigs were inspected for eggs, and the liver and bile ducts of rabbits were examined histopathologically. The overall prevalence of infection among the human subjects was 0.70%, with rates of 0.6% in Curico, 0.75% in Talca, and 0.71% in Linares. The prevalences of infection in horses, rabbits, and pigs were 13.5%, 6.1%, and 20.6%, respectively. It is estimated that some 2,000 people are infected in the study area. It is recommended that rabbits be taken into account in all control programs for this zoonosis.

Adolescent↗
PubMed1992

[Fascioliasis in populations of rural areas with high prevalence of animal infection].

Between January 1986 and December 1990 the prevalence of F. hepatica infection was studied in 5861 rural inhabitants of the provinces of Curico, Talca and Linares, VII Region, an hyperendemic zone of animal fascioliasis. Every one was screened by intradermal (IDR), complement fixation (CF), double diffusion (DD) counterelectrophoresis (CIEF), immunoelectrophoresis (IEP) and enzyme-linked immunoabsorbent assay (ELISA) tests. 366/1881 (9.3%) had positive IDR; 61 (1.04%) positive CF; 14 (0.24%) positive DD and 105/3838 (2.73%) positive ELISA and thus considered under suspicion to be infected. F. hepatica eggs were searched in stool in 241 of these persons. 37 cases were thus confirmed. Another 4 individuals with positive immunobiological tests and absence of the parasite eggs in stools were confirmed by duodenal intubation. 21 of the confirmed cases (51.2%) had less than 15 years of age. Women were more frequently infected than men (73.2% vs 26.8%). The 41 cases represent 0.7% of the surveyed population predicting 2000 cases among the total rural population of these provinces (300,000 persons). These results indicate that human fascioliasis is an important problem in the zone, perhaps much higher if family contacts of the index cases and symptomatic persons are included.

Adolescent↗
PubMed1988

Determination of the molecular weight of proteins by electrophoresis in slab gels with a transverse pore gradient of crosslinked polyacrylamide in the absence of denaturing agents.

The molecular weight of proteins under nondenaturing conditions can be determined through polyacrylamide electrophoresis by comparing their relative mobilities at different gel concentrations with the relative mobilities of standard proteins under the same conditions (J. L. Hedrick and A. J. Smith (1968) Arch. Biochem. Biophys. 126, 155). This work describes a procedure that eliminates the need for several gels of different acrylamide concentrations with the use of a slab gel with a transverse pore gradient of crosslinked polyacrylamide.

Electrophoresis, Polyacrylamide Gel↗