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Biomedical subjects

L Madrigal

Publications and source records attributed to L Madrigal.

34 records · Page 2Linked to original sources
PubMed1993

Flow cytometric analysis of surface major histocompatibility complex class II expression on human epithelial cells prepared from small intestinal biopsies.

A technique for preparing viable, single cell suspensions of the epithelial layer of small intestinal tissue obtained endoscopically is described. Constant agitation of four biopsies for 60 min in the presence of chelating and reducing agents gave yields of 1.2-6.7 x 10(6) cells, of which 11-30% were intraepithelial lymphocytes (IEL). Passage through a nylon wool column removed dead cells. This preparation was suitable for flow cytometric analysis. Using this technique, surface MHC class II molecule expression was studied in 14 patients with normal small intestinal mucosa. Fluorescence labelling of these cells showed strong HLA-DR expression by epithelial cells (EC), DP was expressed less strongly, while little DQ expression could be detected. This technique demonstrates that small intestinal biopsies taken during routine endoscopy can yield adequate numbers of viable epithelial cells to perform flow cytometric analysis.

Adolescent↗
PubMed1993

Intrahousehold allocation of resources in larger and smaller Mexican households.

This paper focuses on aspects of intrahousehold allocation of resources. It suggests that there is a first step involved in understanding household decisions as to allocation or misallocation of food within the household, which is that of understanding intrahousehold allocation of income. In this study, carried out in northwestern Mexico, what has been reported in the literature as examples of unequal access to food, particularly in larger households, may better be considered examples of lack of access on the part of purchasers of household food to all of the income which comes into the household.

Decision Making↗
PubMed1993

Lack of birth seasonality in a nineteenth-century agricultural population: Escazú, Costa Rica.

Demographic studies repeatedly indicate that human births tend to fluctuate in a seasonal pattern, particularly in agricultural groups. Interestingly, lack of seasonal variation has been infrequently reported. Recently, Arcury et al. (1990) indicated that only one published study identified a population in which no seasonality of births was demonstrated. Here, I report the results of a historical demographic study that investigates whether Escazú, a nineteenth-century population from Costa Rica, experienced birth seasonality. The data set consists of certificates of baptisms from 1851 to 1901 collected at the Parish of San Miguel de Escazú, Costa Rica. The data are an accurate reflection of the actual number of births in the population because even newborn infants who appeared to be in imminent danger of dying (and who subsequently did) were baptized. The baptism series was analyzed by fitting an ARIMA model (0, 1, 1) and cross-correlating it with two climatic series: rainfall and temperature. The autocorrelation analysis of the baptism data fails to demonstrate any cyclical pattern of births in Escazú. Moreover, there is no indication that temperature or rainfall influences the frequency of births. This lack of seasonality is unexpected in an agrarian population such as Ecazú. The results of this analysis indicate that human fertility cycles might not be as prevalent as previously thought.

Agriculture↗
PubMed1992

Differential sex mortality in a rural nineteenth-century population: Escazu, Costa Rica.

Cross-cultural studies of sex-specific mortality indicate that, whereas males experience their greatest mortality in industrialized societies, females experience their greatest mortality in populations with low life expectancy. The higher mortality of females in low-life-expectancy communities has been interpreted as a reflection of nutritional and health-care discrimination against females. Cross-cultural demographic studies also indicate that males have a higher frequency of violent and accidental deaths, possibly because of more frequent risky behaviors. This study focuses on Escazu, a rural nineteenth-century population from Costa Rica with low life expectancy. I investigate whether Escazu males had higher violent and accidental deaths and whether females had higher diarrhea-related deaths, an indication of nutritional discrimination. An analysis of mortality by cause of death indicates that males and females did not experience significantly different diarrhea-related death rates, although males did experience greater violent mortality. This study illustrates that more anthropological community-specific studies of mortality are needed to elucidate variation of death rates within large national or international regions.

Cause of Death↗
PubMed1991

Pulmonary hydatidosis in childhood. Review of 21 cases.

Spain is one of the countries with a very high incidence of hydatidosis in the childhood. It represents 16.8% of all cases intervened for thoracic surgery for hydatidosis cysts in our department during the last ten years with a total of 21 children (inferior to 14 years) operated due to hydatidosis. Cough and pain were the symptoms more frequently encountered. The ratio unruptured/ruptured cysts was 3/1, higher than in the adults, with an average of 2.62 cysts per patient. Specific immunoglobulin E and histamine liberation test were the most useful tests in the laboratory. The usual surgical technique was a cystopericystectomy with total extirpation of the parasite of its rests. No recurrence was found in the follow-up of our patients.

Adolescent↗
PubMed1990

Thoracic surgery in the elderly: review of 100 cases.

One hundred cases surgically intervened due to thoracic pathology between 1977 and 1986 were studied. The ages were equal to or higher than 70 years. Mean age was 73.13 years (70-91). In 70 cases a neoplastic aetiology existed (78.57% of primary bronchial carcinoma), while in the other 30 cases the cause was not neoplastic. In these cases with a high operative risk, a detailed systematic study before surgery is recommended, which should be treated in the most conservative possible way. Although the complication rate was higher than the average in other groups (p less than 0.05), mortality was only 4%, being related, to a greater or lesser extent--, to the surgery (p less than 0.05). In the cases diagnosed as bronchial carcinoma, a 2-year survival was obtained in 66.4%, 3 years in 49.8% and 5 years in 25.7%, concluding that an age equal to, or higher than, 70 years does not represent any contraindication for thoracic surgery.

Age Factors↗
PubMed1990

Bilateral spontaneous pneumothorax associated with metastasis of a malignant fibrohistiocytoma.

The case of a 34-year-old female patient is presented. The patient was admitted because of bilateral pneumothorax caused by the metastasis of a malignant histiocytoma originating in the left gluteus. Bilateral chest-suction was made and the patient received complex chemotherapy. The chest X-ray taken 4 months later showed considerable regression of the lymph node metastases. Neither the time of development of pneumothorax nor its mechanism is known. There are only assumptions about it. Authors have considered their case worthy of publication because the lymph node metastasis of bilateral simultaneous pneumothorax due to histiocytoma has not so far been known in the literature.

Adult↗
PubMed1989

Subglottic inflammatory pseudotumor in a 6-year-old child.

Inflammatory pseudotumors have been given diverse--no fewer than 19--names in the literature. The most frequent localization is in the lung, the gastrointestinal tract, and salivary glands. The case presented here at the subglottic level is exceptional. Although the intraoperative diagnosis is not easy, the prognosis is usually good. Malignant degenerations have not been described. In those cases that cannot be operated on or that extend into the mediastinum, radiotherapy is indicated.

Child↗
PubMed1989

Surgical treatment of thoracic hydatidosis. A review of 100 cases.

Hydatid cystic disease continues to hold an important place in chest disease in our country. The authors review their experience from 1977 to 1987 of 100 patients who underwent surgery for pulmonary hydatidosis. Mean age was 36.21 years. Fifty-nine cases were ruptured cysts (RC) and 41 were unruptured cysts (UC). The diagnosis was based on epidemiological, radiological and mainly serological and endoscopic criteria. The indirect haemagglutination test was positive in 100% of RC and 80% of UC, while 70.2% of the patients who underwent fiberoptic bronchoscopy showed pathological changes. The most commonly used surgical procedure in UC was open subtotal cystopericystectomy (89.09%), while wedge resection (41.81%) was the most commonly used technique for the RC. There were no operative deaths and no recurrences were observed for a mean follow-up of 5.4 years. The indications for adjuvant chemotherapy with mebendazole are presented.

Adult↗
PubMed1989

Hemoglobin genotype, fertility, and the malaria hypothesis.

Epidemiological and clinical studies (Fleming et al. 1985; Perrin et al. 1982) indicate that hemoglobin (Hb) AS individuals have a selective advantage in malarial environments. Thus the high frequency of Hb S in human populations has been attributed to the decreased malarial morbidity and mortality experienced by Hb AS heterozygotes. It has also been suggested that Hb AS women have a higher fertility than that of Hb AA women, thus contributing to the elevated frequency of Hb S in malarial environments (Livingstone 1957). Firschein (1961) demonstrated a significantly greater fertility among Hb AS females, whereas Custodio and Huntsman (1984) documented no fertility differential between Hb AS and Hb AA women. Here I examine the reproductive careers of Hb AA and Hb AS subjects 40 years of age and older from Limon, Costa Rica. The purpose is to determine whether normal homozygotes and heterozygotes have significantly different fertilities. The research shows that these groups do not have significantly different completed family sizes (t = 0.38, ns) or significantly different numbers of pregnancies (t = 0.34, ns), live births (t = 0.36, ns), or abortions (t = 0.20, ns). My results support previous suggestions that differential fertility does not contribute to the maintenance of the Hb S polymorphism.

Adult↗
PubMedDate not supplied

Frequency of twinning in two Costa Rican ethnic groups: an update.

Variation in the frequency of twinning among human populations has been presumed to reflect genetic differences. It has been commonly reported that populations of African ancestry have the highest, those of Asian ancestry the lowest, and those of European and Middle-Eastern ancestry intermediate frequencies of twinning. Populations from the Americas have been reported to have intermediate twinning frequencies, presumably reflecting their admixture. In this context, Madrigal (1994. Am J Hum Biol 6:215-218) reported virtually identical (and high) twinning frequencies in two Costa Rican ethnic groups, one of African, the other of Euro-Amerindian ancestry. These frequencies were interpreted in light of frequent inter-ethnic unions, and it was predicted that the two groups would not differ substantially in gene frequencies of several blood enzyme systems. This paper reports the gene frequencies of both groups for such systems. The samples differ significantly for systems that have clearly different frequencies in African and European populations. Given that the groups are actually different in gene frequencies and not homogenous as predicted earlier, the conclusion that twinning frequencies are similar as a result of a similar genetic make up can be questioned. The results challenge the assumption that if populations have similar twinning frequencies it is because they are genetically similar and argue for a stronger environmental component for twinning frequencies.

Costa Rica↗
PubMedDate not supplied

[Detection of antibodies to beta-amyloid in carriers of E280A mutation in the presenilin-1 gene].

OBJECTIVE: To investigate some immune component that could contribute to the pathogenesis of Alzheimer's disease associated with the E280A mutation of the presenilin-1 gene (PS-1). PATIENTS AND METHODS: Serum antibodies against both cardiolipin and beta-amyloid peptides (beta 1-40 and beta 1-42) were quantitated by means of an indirect ELISA technique in carriers of the mutation, either healthy or with Alzheimer's disease, as well as in normal controls without the mutation. RESULTS: Out of 19 patients with Alzheimer's disease only 2 had increased values of antibodies to cardiolipin, namely: one with 14.58 micrograms/ml of IgM and the other with 36.16 micrograms/ml of IgG. The remaining individuals revealed values under 10 micrograms/ml, considered normal, and there was no significant difference between the groups. Significant serum reactivity (p < 0.001) was detected against both beta-amyloid peptides in the mutation carriers, either with or without Alzheimer's disease, as compared to the control group. No correlation was detected between this antibody response and the mental or functional situation of the patients. CONCLUSION: beta-amyloid antibodies, present in the mutation carriers, may simply represent a marker of immune activation induced by beta-amyloid with no in vivo effect; however, despite the results, the possibility can not be ruled out of a pathogenic role of these antibodies in early onset Alzheimer's disease.

Adult↗
PubMedDate not supplied

[Factorial and discriminant analyses of neuropsychological variables in familial and sporadic late onset Alzheimer disease].

INTRODUCTION: Prevalence of late onset Alzheimer's disease (LOAD) both familial and sporadic is increasing with the raising proportion of third-age population. There are evidences either supporting or rejecting the existence of differences in the behavior of neuropsychological variables between familial and sporadic cases of LOAD. OBJECTIVE: To identify neuropsychological variables discriminating between familial and sporadic cases of LOAD, in order to detect clinical manifestations that may provide information on the pathological process of the neurodegenerative process. PATIENTS AND METHODS: Using sequential sampling, we selected individuals affected by LOAD according to the criteria of the DSM-IV and NINCS-ADRDA. The following neuropsychological protocol was used: CERAD, Wisconsin, Phonological Fluency, Rey's Figure, Raven, A Cancellation Test, WAIS (Arithmetic); also used were: Global Deterioration Scale, Functional Assessment Staging of Reisberg (FAST), Barthel and Yesavage. Parametrical and non-parametrical univariate, factorial (principal components) and discriminant analyses were performed. In total, 52 patients were analyzed (average age: 74.8 years; mean age at onset of the disease: 69 years; time of disease's evolution: 5.7 years; average of educational level: 6.4 years). RESULTS: No significant statistical differences were found in clinical or neuropsychological variables between familial and sporadic cases of LOAD. Additionally, neither variables nor models were detected discriminating significantly between them. CONCLUSION: Familial and sporadic cases of LOAD present the same clinical and neuropsychological phenotype which makes very probable that sporadic cases are low penetrance familial ones.

Age of Onset↗