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R Calderón

Publications and source records attributed to R Calderón.

14 recordsLinked to original sources
PubMed1995

Sex linked versus autosomal inbreeding coefficient in close consanguineous marriages in the Basque country and Castile (Spain): genetic implications.

Pedigree structures of 161 uncle/niece-aunt/nephew and 4420 first cousin consanguineous marriages registered during the 19th and 20th centuries in two large and very different Spanish regions have been analysed and their genetic consequences evaluated. The frequencies of the different pedigree subtypes within each degree of relationship were quite similar in both populations despite significant heterogeneity in inbreeding patterns. The mean X-linked inbreeding coefficient (Fx) for each type of cousin mating was calculated and compared to that expected for autosomal genes (F). The effect of genealogical structure on the Fx/F ratio was compared to different cultural populations worldwide. Preferentiality and avoidance of close consanguinity along with specific types of pedigrees are discussed on the basis of premarital migration and sociocultural rules still deeply rooted in certain human groups. By admitting that the observed Fx coefficient is usually higher than F in most human populations some remarks have been made in terms of population genetic risk.

Chromosome Aberrations↗
PubMed1993

Inbreeding patterns in the Basque Country (Alava Province, 1831-1980).

A considerable number of studies have shown that Spain is one of the countries on the European continent with a high level of inbreeding and that, in general, this level decreased more quickly and later than the levels in the rest of Europe. The types and frequencies of consanguineous marriages (up to third cousins), the mean inbreeding coefficient, and secular trends have been studied within the Basque Country (Alava Province) using information from ecclesiastic dispensations from 1831 to 1980. A total of 5583 consanguineous marriages were registered in Alava over the whole period (150 years), and 79 different categories of relationship were observed. The analysis of the structure of consanguinity has shown some appreciable levels of close consanguineous unions: 0.08% (uncle-niece or aunt-nephew marriages) and 0.96% (first-cousin marriages) of the total number of marriages. This seems to be a common phenomenon among provinces of northern Spain. The rates of total consanguinity and the mean coefficient of inbreeding in the population of Alava from 1861 to 1980 were 4.62% and 0.00124, respectively. The temporal trend pattern of inbreeding in Alava closely fits the pattern observed in other large European populations: France, Italy, and Belgium. This early fall in the level of inbreeding in Alava compared to the levels found in both large and small populations in central and western Spain might be due to the early industrial development of the Basque Country and the resulting loss of importance of landownership.

Consanguinity↗
PubMed1990

Incidence of red-green color blindness in the Basque population.

The incidence of red-green colour vision defects was studied in a sample of 392 Basque students (174 males and 218 females), using the Ishihara test cards (1987). The frequency of red-green colour blindness was 4.02 percent in the males and 0.46 percent in the females. The colour blindness frequencies found among males are within the range of other Spanish samples. Nevertheless they are lower than the values reported in other European populations.

Adolescent↗
PubMed1984

Lewis phenotypes and secretor character in the "Castilla la Nueva"-region (Spain). ABH and Lewis antigen levels in salivary secretion.

In 1980 blood and saliva samples were taken from Spanish students of the University of Madrid. Red cells were analysed for A1B2BO and Lewis blood groups. Saliva samples were tested to detect the specific group substances ABH, Lea and Leb. A slightly higher frequency of the "le" gene (0.419) was found in our sample as compared to other Spanish samples. The phenotype frequencies of ABH secretors (77.2%) and non-secretors (22.8%) are in the range of other European populations. The levels of A and B antigens of individuals belonging to these blood groups were similar, whereas the average titration of the H substance showed the relation O greater than A2 greater than A1 greater than A1B greater than B. Analysis of variance proved this heterogeneity to be statistically significant. The amount of Lea substance in non-secretors was higher than in secretors. This shows again that the ABH secretor status has some influence on the quantity of this antigen. The average titration of the Leb substance in secretors was higher than that of Lea in individuals belonging to O, A and AB blood groups, but not in those with blood group B.

ABO Blood-Group System↗
PubMed1980

What is your diagnosis? Gastric leiomyoma.

Smooth muscle tumors are the second most common benign tumors of the stomach after adenomatous polyps. Most often they present as solitary submucosal lesion. Occassionally they may be multiple. They usually present as a smooth mass, although they may be pedunculated and rarely present as gastroduodenal intusuception, when they are located in the distal antrum and prolapse into the duodenum. Leiomyomas may be submucosal, intramural or subserosal. Because of this peculiarity they may grow predominantly intraluminal as well as extraluminally.

Humans↗
PubMed1979

Acatalasia in two Peruvian siblings.

The oral findings in two Peruvian brothers, 10- and 11-years-old, with acatalasia are presented. Gingival necrosis and severe alveolar bone destruction were the main oral manifestations. Otherwise the patients were in good health. Thirteen hypocatalasemic individuals, including both parents, were found among 29 relatives of the probands examined from four generations. No other acatalasemic individuals were found. Hypocatalectic relatives of the probands did not have oral lesions, and no other abnormalities were detected. The parents of the affected children were not known to be related; however, both parents and their families come from the same small rural community. The inheritance pattern in the kindred was compatible with an autosomal recessive disorder. It is postulated that the gingival lesions resulted from damage to tissue from hydrogen peroxide generated by organisms in gingival plaque. The hydrogen peroxide cannot be degraded by gingival tissue or by leukocytes genetically lacking the enzyme catalase.

Catalase↗
PubMedDate not supplied

[An anthropologic reflection on genetic epidemiology. On the need of a multidisciplinary approach].

Historically, Epidemiology arose from the need to take steps in forming health care policy, and up until a few decades ago, its interest has centred on illnesses caused by infectious agents. Recent developments in Medicine and Biology have permitted the evaluation of the behaviour of genetic material in vital processes. From these advances arose Genetic Epidemiology which researches the relationship between heredity and illness among human populations defined by their biosocial characteristics. Its primary field of application is in complex aetiology illnesses in which the genotype and the environment interact. Its complexity has inevitably converted it into a multi-disciplinary science. The basic parametres of the population structures, such as parentage and consanguinity, which is what physical anthropologists have been researching in recent years in Spain, form an important data base which must be integrated into future Genetic Epidemiology studies; these studies will result in its natural progression. Significant success is being obtained in this direction in many advanced countries, therefore it is advisable for our health care authorities to do the same and encourage this type of multidisciplinary work which will serve as a basis for a modern and efficient health care policy.

Anthropology, Physical↗
PubMedDate not supplied

[Primary hepatic actinomycosis].

We present a patient complaining of abdominal pain during eighteen months, localized in left subcostal region, weight loss, asthenia and anorexia for the previous 5 months and fever one month before his admission. He presented painful hepatomegaly, leukocytosis, with an increased percentage of mature and inmature neutrophils, anemia, elevated erythrocyte sedimentation, thrombocytosis, hypergammaglobublinemia and dissociated cholestasis. Complementary exams demonstrated the presence of a poorly vascularized occupying process, localized in the left hepatic lobe. Following laparotomy and biopsy-resection of the process in hepatic left lobe, staining revealed isolated, Gram + filaments and histopathological study showed multiple micro-abcesses displaying actinomyces-like characteristics. There was no evidence of any other pathological process except for previous history of dental abscesses and extractions, which could represent the primary focus for hematogenous dissemination. There was satisfactory response to erythromycin.

Actinomycosis↗