Biomedical subjects

F Luna

Publications and source records attributed to F Luna.

At least 19 recordsLinked to original sources

PubMed2003

The effects of superior ovarian nerve sectioning on ovulation in the guinea pig.

The effects on spontaneous ovulation associated with the unilateral or bilateral sectioning of the superior ovarian nerves (SON) were analyzed in guinea pigs at different time intervals of the estrous cycle. Day 1 of the estrous cycle was defined as the day when the animal presents complete loss of the vaginal membrane (open vagina). Subsequent phases of the cycle were determined by counting the days after Day 1. All animals were autopsied on the fifth day of the estrous cycle after surgery. Sectioning the right, left, or both SONs on day 5 (early luteal phase) resulted in a significant increase in the number of fresh corpora lutea. Ovulation increased significantly when the left SON (L-SON) was sectioned during late follicular phase (day 1) and medium luteal phase (day 8). When surgery was performed on days 1 or 8, neither sectioning the right SON (R-SON) nor sectioning the SON bilaterally had an apparent effect on ovulation rates. Similarly, ovulation rates were not affected when unilateral (right or left) or bilateral sectioning of the SON was performed during late luteal phase two (day 12). Unilateral or bilateral sectioning of the SON performed during the early luteal phase (day 5) was associated with a significant decrease in uterine weight. A comparable effect was observed when the L-SON was sectioned during late follicular phase (day 1), or medium luteal phase (day 8). No effects on uterine weight were observed when unilateral or bilateral sectioning of the SON was performed during late luteal phase. Our results suggest that in the guinea pig the SON modulates ovulation, and that the degree of modulation varies along the estrous cycle. The strongest influence of the SONs on ovulation occurs during early luteal phase, and decrease thereafter, being absent by late luteal phase. In addition, sectioning the left or the right SON caused different responses by the ovaries of adult guinea pigs. This paper discusses the mechanisms by which ovulation increased when the SON was surgically cut.

Animals↗

PubMed2002

Twenty nuclear DNA polymorphisms in a Moroccan population: a comparison with seven other human populations.

A south central Moroccan sample was analyzed for 20 nuclear DNA polymorphisms (restriction fragment length polymorphisms). The population was chosen on the basis of available information on its history, making it suitable for comparisons with data from other European populations. The markers analyzed have been studied previously in several human groups from different continents, and data on African and European samples have been compared to evaluate the genetic affinity of the studied sample with other populations, especially with two Spanish groups: Basques and Andalusians. Heterozygosity levels showed intermediate values between the African and European groups and higher than those found so far in an African group for the studied markers. Genetic distances closely matched geographical relationships through neighbor-joining tree and correspondence analysis, the Moroccans being closer to the European groups than the sub-Saharan Africans included in the analysis. Allele distributions revealed specific population associations with large weight of several alleles in the differentiation of some groups. Gene flow from sub-Saharan Africa appears to be relevant in understanding the differentiation of present Moroccan populations.

Africa↗

PubMed2001

Is 'best proven' a useless criterion?

In this article, I examine some proposals for modification of ethical documents regulating research, particularly, the problems that introducing certain economic clauses may pose. I evaluate suggestions that reject the notion of providing the 'best proven diagnostic and therapeutic method' in favor of 'the highest attainable therapeutic method' or 'the proven effective prophylactic, diagnostic and therapeutic methods.' I analyze the plausibility and problems of introducing a double standard and the consequences it may have in developing countries. Finally I highlight the impact these changes may imply for these countries.

Clinical Trials as Topic↗

PubMed2001

Stillbirth pattern in an isolated mediterranean population: La Alpujarra, Spain.

This study attempted to analyze the effect of several factors on the stillbirth pattern in a relatively isolated rural population, La Alpujarra (Spain), during the first half of the 20th century. The study was a retrospective analysis from a total sample of 2199 births to 525 mothers, allowing for birth year of mother, maternal age, parental inbreeding, family size, birth order, sex, single/twin delivery, and birth interval. Binomial probability distribution of stillbirths provided no evidence for any significantly increased risk in relation to family size. Analysis of covariance (ANCOVA) of stillbirth risk in affected families indicated a significant effect for sex of the child, parental consanguinity, and birth year of mother. Logistic regression showed increased risk in twin delivery and pregnancy order one, but not for birth order other than one. Multivariate analysis of variance (MANOVA) testing for differences between affected and unaffected families supported a temporal decrease of stillbirths during the period studied. Although the birth interval average was significantly shorter in affected families (p < 0.0001), this association did not hold, in a more detailed analysis, for individual intervals in these families (p = 0.20). There was no significant effect of maternal age on stillbirths in the whole sample or limited to first pregnancies. These results suggest that birth order one and twin delivery were the main determinants of the stillbirth pattern in La Alpujarra. Furthermore, our data indicate that the decline in stillbirth rate began before medical facilities for perinatal care became available, which was not until after 1950. The temporal decrease in stillbirth rates may therefore be related to an increasing social attention to deliveries rather than to prenatal care medical facilities.

Adult↗

PubMed2000

Determinants of birth interval in a rural Mediterranean population (La Alpujarra, Spain).

The fertility pattern, in terms of birth intervals, in a rural population not practicing contraception belonging to La Alta Alpujarra Oriental (southeast Spain) is analyzed. During the first half of the 20th century, this population experienced a considerable degree of geographical and cultural isolation. Because of this population's high variability in fertility and therefore in birth intervals, the analysis was limited to a homogenous subsample of 154 families, each with at least five pregnancies. This limitation allowed us to analyze, among and within families, effects of a set of variables on the interbirth pattern, and to avoid possible problems of pseudoreplication. Information on birth date of the mother, age at marriage, children's birth date and death date, birth order, and frequency of miscarriages was collected. Our results indicate that interbirth intervals depend on an exponential effect of maternal age, especially significant after the age of 35. This effect is probably related to the biological degenerative processes of female fertility with age. A linear increase of birth intervals with birth order within families was found as well as a reduction of intervals among families experiencing an infant death. Our sample size was insufficient to detect a possible replacement behavior in the case of infant death. High natality and mortality rates, a secular decrease of natality rates, a log-normal birth interval, and family-size distributions suggest that La Alpujarra has been a natural fertility population following a demographic transition process.

Adult↗

PubMed1999

Variation of 17 RFLP markers on chromosome 13 in southeastern Spain.

The allele frequency distribution of 17 nuclear DNA restriction polymorphisms at 15 loci on chromosome 13 was examined in a sample of 70 unrelated autochthonous individuals from La Alpujarra rural mountainous region in Southeastern Spain. The markers typed, 14 associated with anonymous segments and three located on coding regions, constitute a subset from the battery of the nuclear RFLPs previously proposed for population studies (Bowcock et al. 1991). In our sample no Hardy-Weinberg equilibrium deviations were present and the average heterozygosity over all loci was 0.367 +/- 0.031. The significant differences for five markers observed between our sample and a Spanish Basque group underline the usefulness of this kind of DNA markers for the analysis of populations relationships even at the continental level.

Adult↗

PubMed1999

Red cell enzyme polymorphisms in Moroccans and southern Spaniards: new data for the genetic history of the western Mediterranean.

Population samples from Morocco (El Jadida, south Atlantic coast) and La Alpujarra (Granada mountains, Spain), located on both shores of the western Mediterranean, were typed for 8 erythrocyte genetic markers: ACP1, ESD, PGD, AK1, GLO1, PGM1, SODA, and DIA. Genetic heterogeneity within western Mediterranean groups was investigated on the basis of allele frequencies of these 8 polymorphisms plus ABO and Rh (CDE). Only slight peculiarities for the ACP1, GLO1, and AK1 systems were observed in the 2 samples compared with other Mediterranean data. The new data are consistent with a main north to south genetic differentiation in the Mediterranean region. However, with regard to other European groups, the La Alpujarra population shows a particular affinity with North Africans that may be compatible with both an ancient common substratum and/or a special historical influence during the Muslim domination of the Iberian Peninsula.

Adult↗

PubMed1999

Determinants of protogenetic interval in a west Mediterranean rural population: La Alpujarra (southeast Spain).

This paper analyzes the protogenetic interval determinants and the influence on family size. The data came from La Alpujarra (Southeast Spain), consisting on a sample of 847 families marrying through-out the first half of the present century. The marital fertility includes 85% deliveries, 5% premarital births and the remaining 10% premarital conceptions. The protogenetic interval was clearly associated with the reproductive success since family size was nearly one child greater for short intervals (= < 16 months). The protogenetic interval largely depends on the occurrence of miscarriages preceding the first liveborn delivery as well as on maternal age. Consanguineous couples show slightly shorter intervals. A temporal decrease of protogenetic intervals was observed.

Birth Intervals↗

PubMed1998

Genetic drift in present human populations: survey of a Mediterranean region (La Alpujarra, South-east Spain).

This paper presents information on the opportunity for genetic drift in La Alpujarra, a rural population of the Spanish Mediterranean. This region is characterized by its historical isolation. The analyses were based on a survey of 45% of the population. The Effective Population Size (NE = 1986), the Effective Migration Rate (M(E) = 12.4) and the Coefficient of Breeding Isolation (CBI = 246.2) of Lasker & Kaplan (1964) were calculated. The value of the latter index indicates that genetic drift in the Alpujarrenian population is negligible at present because of the cessation of reproductive isolation due to the development of communication networks.

Female↗

PubMed1997

Spontaneous abortion pattern in an isolated Mediterranean population: La Alta Alpujarra Oriental (southeast Spain).

The effects of several family and embryonic factors on the abortion pattern in a rural Mediterranean population (La Alta Alpujarra Oriental, Southeast Spain) were analyzed from interview data on 3163 pregnancies from the first half of the twentieth century. No significant differences in spontaneous abortion rates were detected between endogamous and exogamous couples. The abortion pattern of this population is characterized mainly by family and embryonic factors. High rates of early abortions were significantly associated with maternal age and pregnancy order, and parental consanguinity was linked with a notable decrease of abortion frequency during the earlier stages of pregnancy. A tendency toward a higher risk for abortion was also confirmed for twinship of the fetus. The interactions identified between abortion risk and maternal age, pregnancy order, and inbreeding emphasize the important contribution of sociodemographic factors to prereproductive mortality in human populations.

Abortion, Spontaneous↗

PubMed1991

A fast staining method for CNS slices.

We describe a staining technique for quick observation of the microanatomy of the vertebrate CNS. Successive soaking of the sections in tannic acid and ferric chloride produces a black colour in the gray matter. The procedure takes 5 min and is useful for identifying electrode penetrations, localization of lesions or teaching neuroanatomy.

Animals↗

PubMed1990

Reproductive pattern in a rural Mediterranean population: La Alpujarra, Spain.

The reproductive pattern of a sample of nuclear families from La Alpujarra (Andalusia, Spain) is analysed. The origin of the wife or consanguinity of the couple does not influence fertility. Variability in number of pregnancies is most closely associated with marriage duration followed by the wife's year of birth. Differences in the number of births are explained more by the number of pregnancies than by the number of miscarriages. The number of survivors to the first birthday is dependent on the number of births and to a lower extent on infant mortality. Data from incomplete families show that reproductive performance of the wife below the age of 45 cannot be accepted as a reliable estimate of complete reproduction.

Adolescent↗

PubMed1989

Distribution of middle phalangeal hair in a population of the south of Spain.

In this paper the presence or absence of middle phalangeal hair has been studied in an Andalusian population sample. This sample consists of 245 students from Granada (128 males and 117 females). The frequencies of middle phalangeal hair are similar to those obtained in the Basque population, which show the lowest frequencies so far reported. In our sample no significant sexual or bimanual differences are seen. The most affected finger is the ring-finger, the least affected one is the forefinger. The phenotypes were classified according to the nomenclatures given by Valls and Bernstein.

Adult↗

PubMed1987

Hepatic glucose extraction in normal and diabetic man.

Fractional hepatic extraction of glucose was determined from the appearance in the systemic circulation of ingested 3-[3H]glucose. Using the glucose clamp technique, studies were done under steady-state conditions of basal glycemia and insulinemia, normoglycemia (0.8 mg/mL) and mild hyperinsulinemia (approximately 40 microU/mL), hyperglycemia (2 mg/mL-1) and hyperinsulinemia (approximately 100 microU/mL). Based on previous results in the dog, an oral glucose load of 2 g was used to label the portal vein glucose; this amount was chosen so as to minimize disturbance of the portal steady state but still avoid excessive loss during absorption. Additional subjects with hyperglycemia and hyperinsulinemia received an oral load of 50 g of glucose. Fractional extraction in normal subjects under near-basal conditions of glycemia and insulinemia was 19% in normal subjects and in patients with noninsulin-dependent diabetes mellitus (NIDDM) elevation of serum insulin, with or without hyperglycemia, which led to an average extraction rate of 32% of the ingested glucose. Absolute hepatic glucose uptake, calculated from the fractional extraction the plasma glucose concentration, and hepatic plasma flow accounted for 50% to 72% of total glucose use during the various steady states and following ingestion of 50 g of glucose. It is concluded that hepatic uptake or extraction, as opposed to net uptake, proceeds actively even when plasma glucose and insulin are within the normal basal range; it is increased in the presence of hyperinsulinemia, with or without hyperglycemia; and it is unaltered in NIDDM.

Adult↗

PubMedDate not supplied

Seventy-three nuclear DNA polymorphisms in a Spanish population and a comparison with ten other populations.

An anthropologically well-defined Spanish sample from La Alpujarra (SE Spain) was analyzed for 73 nuclear DNA polymorphisms. The population was chosen on the basis of available information on its history and demographic characteristics making it suitable for comparisons with data from North African populations. The Moslem invasion in this area was longer than anywhere in the Iberian Peninsula (more than nine centuries). The markers analyzed have been studied previously in 10 human populations from different continents. The Alpujarrenian population was checked for these markers and it is the one with the highest number of chromosomes analyzed. Two new alleles were sized and heterozygosity levels were very similar to other European populations. Genetic distances closely matched geographical relationships both with neighbor joining tree and principal component analysis. Allele distributions revealed specific associations with some populations. This work reveals the importance of these markers for evolutionary studies of human populations.

Africa, Northern↗

PubMedDate not supplied

Genetic relationships among Berbers and South Spaniards based on CD4 microsatellite/Alu haplotypes.

BACKGROUND: CD4 STR/Alu haplotype diversity, both for its qualitative and quantitative properties, has been widely used in molecular anthropology to clarify the degree of genetic relationships among human populations. AIM: CD4 STR/Alu variation was studied in two West Mediterranean samples, Andalusians from La Alpujarra region on the north side of the Gibraltar Strait and Berbers from the south, to ascertain the pattern of affinities between them. SUBJECTS AND METHODS: Alu and microsatellite alleles were tested in 99 Andalusians from La Alpujarra region (Southeast Spain) and 124 Middle Atlas Berbers (Morocco). RESULTS: Two new combinations of Alu and STR alleles (75(+) and 80(-)) were found in Berbers. The CD4 STR/Alu haplotype distribution in South Spaniards is similar to that of other Europeans, the only special feature is the slight presence of the 90(+) and 130(+) typical Sub-Saharan haplotypes. The Berber sample is characterized by a high number of different haplotypes (18) with intermediate heterozygosity values (0.846) in comparison with other North African groups, and by a high frequency of the 110(-) combination that has been proposed as representative of an ancient Northwest African population. CONCLUSION: A geographical gradient of Sub-Saharan gene contribution has been detected in North Africa. The Middle Atlas Berbers showed an intermediate value in comparison with the high and low values found in Mauritanians and Moroccan Berbers, respectively. The analysis of the CD4 STR/Alu haplotype variation failed to indicate any particular relationship between South Spaniards and North Africans.

Alu Elements↗

PubMedDate not supplied

Mechanisms of natural selection in human rural populations, survey of a Mediterranean region (La Alpujarra, SE Spain).

Measures of fecundity and mortality among 476 women from a Mediterranean population in SE Spain (La Alpujarra) have been used to estimate the possibilities of the action of natural selection, using Crow's Index of Total Selection. The component due to differential fecundity was twice that attributed to mortality. The Crow's index variation in different populations seems to reflect a change in the action model of evolutionary factors from a primitive situation characterized by high mortality to a new situation typified by very low fecundity. The intermediate step could be represented by the rural communities defined by a sharp decrease of mortality while fecundity remains high. The selection potential found in La Alpujarra was in the range corresponding to these rural groups.

Adult↗

PubMedDate not supplied

Digital dermatoglyphic patterns of Moroccan Arabs: relationships with Mediterranean populations.

Dermatoglyphic finger patterns and pattern intensity were examined in a sample of 204 (105 males and 99 females) adults from the authochthonous Arab population of south central Morocco. No significant sex differences were found for the overall finger pattern incidence or for the pattern intensity index. A high incidence of arches is the most remarkable characteristic of this population as compared to other Mediterranean groups. The significant differences from two previous sets of Moroccan data indicate a remarkable heterogeneity within the present day Moroccan population. Also important is the differentiation of this sample from other north African ethnic groups such as Berbers and Tuaregs. An analysis of the dermatoglyphic relationships using R-matrix analysis, shows a relative proximity between this Moroccan series and other southwest European groups as compared to north African populations.

Adolescent↗