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Biomedical subjects

L Madrigal

Publications and source records attributed to L Madrigal.

At least 19 recordsLinked to original sources
PubMed2005

[Improvements in lung preservation: 3 years' experience with a low-potassium dextran solution].

OBJECTIVE: Lung preservation quality is a crucial factor in the success of a lung transplant. In October 2000 we stopped using Euro-Collins (EC) lung preservation solution and began using a low potassium dextran solution (Perfadex [PER]). The objective of the present study was to assess outcome with the 2 solutions. MATERIAL AND METHODS: We analyzed the results of 68 lung transplants in which PER was used and compared the results with those of a historical control group consisting of the same number of transplants in which EC was used. RESULTS: There were no significant differences in the ages and diagnoses of the recipients in the 2 groups. Waiting list time was longer in the PER group. The most frequent cause of donor death in the EC group was craniocerebral trauma (62%), whereas in the PER group it was cerebral hemorrhage (54%). In the PER group more double lung transplants were performed than in the EC group (78% and 53% respectively; P=.002). There were no differences in the use of extracorporal circulation or ischemia time between the 2 groups. Early graft function, based on the patient's oxygenation index (ratio of PaO2 to inspired oxygen fraction [FiO2]) on arrival at the intensive care unit, was similar in the 2 groups. The incidence of severe graft failure (PaO2/FiO2<150 mm Hg) was significantly lower in the PER group than in the EC group (16% and 37% respectively; P=.01). No significant differences in hours of mechanical ventilation or postoperative mortality between the 2 patient series were found. CONCLUSIONS: Use of the newer lung preservation solution --PER-- led to a 50% lower incidence of severe ischemia-reperfusion graft injury during the early recovery from lung transplantation.

Adolescent↗
PubMed2003

Widow and widower remarriage: an analysis in a rural 19th century Costa Rican population and a cross-cultural discussion.

Although the topic of remarriage features saliently in the cultural anthropological literature, it is virtually absent in the biological anthropology journals. This is perplexing, given that remarriage affects the differential reproductive success of males and females in a community, and could well impact a community's population structure. In this paper, we research remarriage practices in a rural 19th century community in Costa Rica. Although we find support for the proposition that males are more likely to remarry than females, we find that widows who remarry are not all young and able to reproduce. Our findings support the cross-culturally-generated suggestion that a female's ability not to remarry is tied to her to ability to own property. Remarriage is a topic of interest to biological anthropologists from a cross-cultural and biocultural perspective.

Age Factors↗
PubMed2003

Epidemic cycles in agricultural populations: a cross-cultural study.

A cross-cultural analysis of mortality patterns is of interest to biological anthropologists and genetic epidemiologists. In this paper, we examine four agricultural populations from Costa Rica, Hungary, and the United States in order to determine if they suffered from a cyclical distribution of epidemics. When possible, we look at the mortality time series of adults and children separately. Of the 2 series, only 2 show significant epidemic cycles. Both are in the Hungarian groups and both affect subadults. Otherwise, the Costa Rica, U.S., and adult series of the Hungarian groups do not show any periodicity of mortality peaks. Our results indicate that epidemic cycles are not as ubiquitous in small agricultural groups as the literature would suggest.

Adolescent↗
PubMed2001

Presenilin-1-associated abnormalities in regional cerebral perfusion.

OBJECTIVE: To investigate the influence of the presenilin-1 gene (PS-1) mutation on regional cerebral perfusion, SPECT was evaluated in 57 individuals. The subjects were members of a large pedigree from Colombia, South America, many of whom carry a PS-1 mutation for early-onset AD. METHODS: Members of this large kindred who were cognitively normal and did not carry the PS-1 mutation (n = 23) were compared with subjects who were carriers of the mutation but were asymptomatic (n = 18) and with individuals with the mutation and a clinical diagnosis of AD (n = 16). Cerebral perfusion was measured in each subject using hexamethylpropyleneamine oxime SPECT. The data were analyzed in two ways: 1) Mean cerebral perfusion in each of 4320 voxels in the brain was compared among the groups using t-tests (t-maps); and 2) each individual received a weighted score on 20 vectors (factors), based on a large normative sample (n = 200), using a method known as singular value decomposition (SVD). RESULTS: Based on t-maps, subjects with the PS-1 mutation who were asymptomatic demonstrated reduced perfusion in comparison with the normal control subjects in the hippocampal complex, anterior and posterior cingulate, posterior parietal lobe, and anterior frontal lobe. The AD patients demonstrated decreased perfusion in the posterior parietal and superior frontal cortex in comparison with the normal control subjects. Discriminant function analysis of the vector scores derived from SVD (adjusted for age and gender) accurately discriminated 86% of the subjects in the three groups (p < 0.0005). CONCLUSION: Regional cerebral perfusion abnormalities based on SPECT are detectable before development of the clinical symptoms of AD in carriers of the PS-1 mutation.

Adult↗
PubMed2001

Ethnicity, gene flow, and population subdivision in Limón, Costa Rica.

In this paper we examine the effects of ethnicity on the gene flow between two groups living in Limón, Costa Rica. Our main interest is to determine if ethnicity has acted as a barrier to the exchange of genes, and if the groups have remained distinct genetically. We report the admixture estimates, F(st) values, and inbreeding coefficients of the two samples. The data consist of blood samples and surnames obtained from 375 individuals. The subjects' two surnames were analyzed to determine the ethnicity of their parents (individuals carry their father's and mother's first surnames). We used the formula of Crow and Mange ([1965] Eugen Q 12:199-203) to compute F(t), F(n), and F(r) with the surnames. Admixture estimates were computed for both groups using the computer program ADMIX.PAS kindly provided by Jeffrey Long. The estimates for the Hispanic-Limonense group are M1 = 0.5866 European, M2 = 0.3383 Amerindian, and M3 = 0.0751 African ancestry. For the Afro-Limonense group, the admixture estimates indicate M1 = 0.1047 European, M2 = 0.1357 Amerindian, and M3 = 0.7595 African ancestry. The F(st) values are F(st) = 0.00558 for the Hispanic group and F(st) = 0.05137 for the Afro-Limonense group. These F(st) values indicate that the Afro-Limonense group has experienced more genetic drift than has the other group, possibly as a result of its long history of isolation in Costa Rica. Indeed, when plotted along a scaled eigenvector R matrix of Caribbean gene frequencies, the two Limonense groups did not cluster with each other. Thus we conclude that the two ethnic groups have remained distinct breeding populations.

Adult↗
PubMed2000

Neuropsychological profile of a large kindred with familial Alzheimer's disease caused by the E280A single presenilin-1 mutation.

It was hypothesized that subjective memory complaints represent the earliest sign of dementia in carriers of the presenilin-1 (PS1) mutation. A total of 122 subjects (44 males, 78 females) were included in this study. Forty of them were positive for the mutation in the PS1 gene (mutation positive, MP) whereas 82 showed negative results (mutation negative, MN). Subjects were active, functionally normal, even though some of them complained of memory difficulties. Two groups of neuropsychological instruments were administered: (a) The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological test battery (Morris et al., 1989), and (b) some additional neuropsychological tests (Raven Test, Wechsler Memory Scale, Rey-Osterrieth Complex Figure, Boston Naming Test, Naming of Categories, Boston Diagnostic Aphasia Examination, Memory of Three Phrases, Knopman Test, Digit Symbol, and Visual "A" Cancellation Test). Performance in both groups was quite similar. In a secondary analysis, the MP group was subdivided into two subgroups: without and with memory complaints. When comparing both subgroups, a better performance in the first subgroup was found throughout the different subtests. Statistically significant differences were observed in the following test scores: Mini-Mental State Examination, Naming Test (Low Frequency), Memory of Words Test, Recall of Drawings, Wechsler Memory Scale (Logical Memory, Associative Learning, and Total Score), Rey-Osterrieth Complex Figure (Immediate Recall Condition), Boston Diagnostic Aphasia Examination (Complex Ideational Material Subtest), Memory of Three Phrases Test, Serial Verbal Learning (maximum score and Delayed Recall), Knopman Test (First Trial, Second Trial, and Recall after 5 Minutes), Digit Symbol, and Visual "A" Cancellation Test (Additions). Results supported the hypothesis that memory complaints represent the earliest symptom of familial Alzheimer's disease. In addition to the memory difficulties, other minor cognitive impairments were also found, particularly, mild anomia, concentration difficulties and defects in the understanding of complex verbal material.

Journal Article↗
PubMed1999

Mating pattern and population structure in Escazú, Costa Rica: a study using marriage records.

A primary focus of historical demographic research is to understand how a population's mating pattern can affect its genetic structure. By using surnames, researchers can reconstruct gene flow into a population as well as within it: the population structure. Indeed, Lasker (1988a) noted that the distribution of surnames reflects the effect of mate choice on a population's genetic structure. Here, we study the mating pattern of a small, clearly established breeding population in Costa Rica (Escazú) during 1800-1839 and 1850-1899. We found that a large proportion of marriages involved individuals who were members of long-standing or core families. Indeed, 27 families provided 56% of all consorts throughout the period under study. When new surnames appeared in the records (presumably as a result of immigration), they were introduced more frequently by males, indicating that more males than females migrated into the community. The core families did not mate preferentially among themselves but appear to have readily accepted the migrants. Indeed,the greatest preponderance of repeated-surname marriages was that expected by chance. However, nonrandom surname repetition is evident when marriages between nonillegitimate consorts are analyzed. That is, the frequency of repeated-pair surname marriages is statistically significant in marriages involving brides and grooms who carried 2 surnames. Interestingly, significant departures from random repetition of surnames occurred during the decade in which the great cholera epidemic affected Costa Rica and during the decade following it. This departure from panmixia supports the notion that mating patterns were altered as a result of the epidemic, a suggestion we made previously when we reported that inbreeding increased in these same decades (Madrigal and Ware 1997).

Catholicism↗
PubMed1997

Clinical features of early-onset Alzheimer disease in a large kindred with an E280A presenilin-1 mutation.

OBJECTIVES: To characterize clinical features of a very large pedigree with early-onset Alzheimer disease (AD) in which all affected individuals carry the identical glutamic acid-to-alanine mutation at codon 280 in the presenilin-1 gene. DESIGN: Clinical histories were obtained by patient and family interviews and through medical or civil records. Using standard diagnostic criteria, a case series of 128 individuals was identified, of which 6 have definitive (autopsy-proven) early-onset AD, 93 have probable early-onset AD, and 29 have possible early-onset AD. SETTING: Community based in Antioquia, Colombia. PATIENTS: A population-based sample in which all members of 5 extended families (nearly 3000 individuals) were surveyed. Criteria for inclusion required obtaining sufficient information to categorize the individual as affected. MAIN OUTCOME MEASURES: Age at onset, neuropsychological profile, neurologic history, and examination. RESULTS: The patients had a mean age at onset of 46.8 years (range, 34-62 years). The average interval until death was 8 years. Headache was noted in affected individuals significantly more frequently than in those not affected. The most frequent presentation was memory loss followed by behavior and personality changes and progressive loss of language ability. In the final stages, gait disturbances, seizures, and myoclonus were frequent. CONCLUSIONS: Other than the early onset, this clinical phenotype is indistinguishable from sporadic AD except that affected individuals frequently complained of headache preceding and during the disease. Despite the uniform genetic basis for the disease, there was significant variability in the age at onset, suggesting an important role for environmental factors or genetic modifiers in determining the age at onset.

Adult↗
PubMed1997

E280A PS-1 mutation causes Alzheimer's disease but age of onset is not modified by ApoE alleles.

A single base substitution of a glutamic acid to an alanine codon 280 was found in the presenilin-1 (PS-1) gene on chromosome 14 in affected individuals in each of seven Colombian early-onset Alzheimer's disease (AD) kindreds. The mutation segregated with disease in kindreds tested. In the largest kindred (C2), the maximum two-point lod score between the mutation and AD was Z = 8.14 at theta = 0. The presence of a single mutation and the common geographic origin, with all families from the state of Antioquia, suggest a founder effect in this population. This finding is supported by the observation of a rare haplotype inherited with AD in all kindreds. These kindreds form the largest collection of AD cases with the same PS-1 mutation and the same educational, environmental, and ethnic background in which to study the phenotypic effect of putative risk factors, such as the epsilon4 allele of apolipoprotein E (ApoE) or head trauma. Of the few AD cases having a history of head trauma, the age of onset was not lowered. No effect of ApoE genotype on the age of onset was detected. Previous investigations of the effect of ApoE genotype on the age of onset were confounded by small patient numbers, familial clustering of ApoE genotypes, and combining data from unrelated families with different mutations.

Adult↗
PubMed1997

Twinning trend in Escazú, Costa Rica, 1851-1901.

The cross-cultural study of secular trends in twinning has been of interest to students of human biology. Although recent vital statistics are likely to be more reliable, older vital records allow a long-term study of twinning trends and of the effect of epidemics on twin incidence. Here, I report the results of an investigation of the secular trend of twin maternities from 1851 to 1901 in Escazú, Costa Rica. The research also investigates whether epidemics affected twin incidence in a consistent manner. Because the church records did not state the mother's age, it was not possible to standardize the raw twinning rate for maternal age. Thus the moving averages of the raw rates for every 33 years (the average length of a generation) were computed to minimize the effect of changing average maternal age on twin incidence. No consistent response to epidemics is apparent in the twinning rates. However, both the raw twinning rates and their moving averages indicate that the frequency of twinning decreased in Escazú during the second part of the nineteenth century. A decline in the twinning rate in other populations is usually attributed to environmental changes caused by the process of industrialization. However, the decline in the twin maternity incidence in Escazú could not be the result of such an environment because the population was rural and nonindustrialized. This study indicates that a decline in twin maternities may result from more diverse causes than was previously thought.

Costa Rica↗
PubMed1997

Inbreeding in Escazú, Costa Rica (1800-1840, 1850-1899): isonymy and ecclesiastical dispensations.

We investigate the inbreeding levels in Escazú, Costa Rica, during 1800-1840 and 1850-1899. Inbreeding was researched through analysis of ecclesiastical dispensations and by two isonymy methods (Crow and Mange 1965; Pinto-Cisternas et al. 1985). As expected, the dispensation inbreeding coefficients were lower than those obtained through isonymy. However, the three methods indicate that consanguinity increased in the community during the second part of the nineteenth century.

Anthropology↗
PubMed1996

[The treatment of tracheobronchial ruptures: a review of 6 cases].

Tracheobronchial ruptures represent a serious pathology difficult to diagnose at the first examination. The authors review 6 cases: four as acute types with pneumomediastinum, pneumothorax and subcutaneous emphysema with a delay in diagnosis of 3.25 days, meanwhile 2 cases were chronic forms with a delay in diagnosis of 124.5 days. Diagnosis should be performed as soon as possible based in the presence of uni or bilateral pneumothorax with pneumomediastinum being confirmed by fiber bronchoscopy. The treatment is based in the resection of the fractured fragments, followed by bronchoplasty always with reabsorbable sutures the most frequent surgical technique, meanwhile in the atelectatic forms it is not possible to perform sometimes and we must practise lung resections.

Accidents, Traffic↗
PubMed1996

The E280A presenilin 1 Alzheimer mutation produces increased A beta 42 deposition and severe cerebellar pathology.

Missense mutations in the presenilin 1 (PS1) gene cause the most common form of dominant early-onset familial Alzheimer's disease (FAD) and are associated with increased levels of amyloid beta-peptides (A beta) ending at residue 42 (A beta 42) in plasma and skin fibroblast media of gene carriers. A beta 42 aggregates readily and appears to provide a nidus for the subsequent aggregation of A beta 40 (ref. 4), resulting in the formation of innumerable neuritic plaques. To obtain in vivo information about how PS1 mutations cause AD pathology at such early ages, we characterized the neuropathological phenotype of four PS1-FAD patients from a large Colombian kindred bearing the codon 280 Glu to Ala substitution (Glu280Ala) PS1 mutation. Using antibodies specific to the alternative carboxy-termini of A beta, we detected massive deposition of A beta 42, the earliest and predominant form of plaque A beta to occur in AD (ref. 6-8), in many brain regions. Computer-assisted quantification revealed a significant increase in A beta 42, but not A beta 40, burden in the brains from 4 PS1-FAD patients compared with those from 12 sporadic AD patients. Severe cerebellar pathology included numerous A beta 42-reactive plaques, many bearing dystrophic neurites and reactive glia. Our results in brain tissue are consistent with recent biochemical evidence of increased A beta 42 levels in PS1-FAD patients and strongly suggest that mutant PS1 proteins alter the proteolytic processing of the beta-amyloid precursor protein at the C-terminus of A beta to favor deposition of A beta 42.

Age of Onset↗
PubMed1996

Sex ratio in Escazú, Costa Rica, 1851-1901.

The long-term behavior of the secondary sex ratio (SSR) is of interest to human biologists partly because it could be responsive to cyclical environmental stress or to long-term changes in the environment. Indeed, the SSR has been reported to fluctuate in a seasonal pattern or to have a long-term trend in some populations but not in others. Here, I study the behavior of the SSR in Escazú, Costa Rica, from 1851 to 1901. Of particular interest is whether the SSR was seasonal, because Madrigal (1994) reported that in this population mortality is seasonal. The data were successfully modeled according to the Box-Jenkins methodology without incorporating a seasonal parameter. Thus the SSR did not fluctuate seasonally. For the time period under study no long-term trend was observed in the value of the SSR, which tended to fluctuate in accordance with the expected values. Finally, the behavior of the SSR was not observed to be influenced by the various epidemics that affected Escazú. These results indicate that, although severe epidemics and seasonal mortality affected the population, the community's SSR was not significantly affected by these stresses.

Costa Rica↗
PubMed1995

Differential fertility of mothers of twins and mothers of singletons: study in Limon, Costa Rica.

The reproductive performance of mothers of twins is of interest from an evolutionary perspective. Because mothers of twins have the potential of leaving a greater number of offspring, they could be favored by natural selection. At the same time, twin pregnancies are known to be associated with higher pre- and postnatal mortality. Thus mothers of twins at least have potentially higher fertility, a potential that may be hampered by greater mortality of twins. Here, I examine the completed fertility of 149 females, 50 years of age and older, from Limon, Costa Rica. In particular, the number of surviving children of mothers of twins and mothers of singletons at the time of the interview is compared. In this sample mothers of twins have a higher fertility at the end of their reproductive career. Their selection coefficient indicates that natural selection favors them through differential fertility.

Costa Rica↗
PubMed1994

Mortality seasonality in Escazú, Costa Rica, 1851-1921.

Mortality seasonality has been frequently reported in populations living under various ecological conditions. The number of deaths apparently varies by month as a result of fluctuating climatic variables. Here, I examine whether mortality was seasonally distributed in Escazú, Costa Rica, from 1851 to 1921. I also investigate which cause of death made the greatest contribution to mortality periodicity and which climatic variable caused the seasonality of deaths. Two different methodological approaches are used: chi-square and Freedman tests to determine the presence of seasonality and Box-Jenkins time series analysis. The tests to determine the presence of seasonality show that mortality was strongly seasonal in Escazú, with the highest number of deaths occurring during the early months of the rainy season. The Box-Jenkins analysis successfully modeled the series from 1851 to 1891 with a seasonal parameter. However, the more recent years of the data were modeled without seasonal parameters. Thus the time series approach indicates that mortality became less seasonally distributed in more recent years. An analysis of gastrointestinal- and respiratory-related deaths showed that gastrointestinal causes had a strong seasonal distribution (with more deaths in the early months of the rainy season) and that respiratory causes did not. Therefore rainfall appears to have been responsible for mortality seasonality through its impact on the frequency of gastrointestinal maladies. The analysis of cause of death also shows that the seasonal fluctuation of gastrointestinal-related deaths decreased in the more recent years. Such a decrease is reflected in the nonseasonal Box-Jenkins model for the 1892-1921 years.

Analysis of Variance↗