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AIM Multidrug-resistant bacterial infections are a public health problem worldwide. However, most of the information available refers to adults. The main objectives were to determine the incidence, risk factors, and outcomes for device-associated infections, especially those involving multidrug-resistant bacteria. METHODS This is a prospective, observational study. Children aged ≥1 month and

OBJECTIVES: Based on the existing sex differences in mortality rates in children, we would like to explore whether girls and boys respond differently under severe health conditions, in terms of mortality and cause of admission. METHODS: We analyzed demographic characteristics (age and sex), causes of admission, clinical parameters, and mortality in a sample of 2,609 patients from a Pediatric Intensive Care Unit (PICU) in a children's hospital in Barcelona, Spain. RESULTS: PICU admittance was significantly higher in boys (57.5% vs. 42.5%) whereas PICU mortality was significantly higher in girls (4.9% vs. 3.3%). Female sex was a risk factor for PICU in-hospital mortality (OR = 1.55, P = 0.033), while increasing age had a protective effect (OR = 0.808, P = 0.021). In cases of PICU mortality, girls died from a broader range of causes and boys were more affected by respiratory and polytraumatic injuries. Boys were affected by polytraumatic injuries throughout the year, less frequently in winter, while girls showed a higher occurrence in holiday months. CONCLUSIONS: Although more boys were admitted to the PICU, a significantly higher number of girls died. Younger age and higher occurrence of nosocomial infection among girls could explain this finding. More frequent polytraumatic injuries in boys could reflect an increased exposure to risky activities and/or more careless behavior. Am. J. Hum. Biol., 2015. © 2015 Wiley Periodicals, Inc. Language: en

The APOE/C1/C4/C2 gene cluster presents high relevance in lipid metabolism and, therefore, has important epidemiological implications. Here, we study for the first time the variation patterns of 25 polymorphisms (10 short tandem repeats, STRs, and 15 single nucleotide polymorphismas, SNPs) in two native Andean samples from Bolivia (45 Aymaras and 45 Quechuas) as well as one European sample (n = 41) as external reference. We estimated diversity parameters, linkage disequilibrium patterns, population structure, and possible selective effects. In general, diversity was low and could be partly attributed to selection (probably due to its physiological importance), since the APOE/C1/C4/C2 region was highly conserved compared to the flanking genes in both Bolivians and Europeans. Moreover, the lower gene diversity in Bolivians compared to Europeans for some markers might indicate different demographic histories. Regarding the APOE isoforms, in addition to ɛ3 (94%) and ɛ4 (5%), isoform ɛ2 (1%) was also detected in Bolivians. In relation to previous hypotheses, our results support that genetic drift or founder effects rather than selection for increased cholesterol absorption are the main factors that have shaped the distribution of APOE isoforms observed in South America.

The variation of 18 Alu polymorphisms and 3 linked STRs was determined in 1,831 individuals from 15 Mediterranean populations to analyze the rela- tionships between human groups in this geographical region and provide a complementary perspective to information from studies based on uniparental markers. Patterns of population diversity revealed by the two kinds of markers examined were different from one another, likely in relation to their different mutation rates. There- fore, while the Alu biallelic variation underlies general heterogeneity throughout the whole Mediterranean region, the combined use of Alu and STR points to a con- siderable genetic differentiation between the two Mediter- ranean shores, presumably strengthened by a consider- able sub-Saharan African genetic contribution in North Africa (around 13% calculated from Alu markers). Gene flow analysis confirms the permeability of the Sahara to human passage along with the existence of trans-Mediter- ranean interchanges. Two specific Alu/STR combina- tions—CD4 110(2) and DM 107(2)—detected in all North African samples, the Iberian Peninsula, Greece, Turkey, and some Mediterranean islands suggest an ancient genetic background of current Mediterranean peoples. Am J Phys Anthropol 141:430-439, 2010. V C 2009 Wiley-Liss, Inc.

Summary The origin of Pacific islanders is still an open issue in human population genetics. To address this topic we analyzed a set of 18 Alu insertion polymorphisms in a total of 176 chromosomes from native Easter Island inhabitants (Rapanui). Available genealogical records allowed us to subdivide the total island sample into two groups, representative of the native population living in the island around 1900, and another formed by individuals with some ancestors of non-Rapanui origin. Significant genetic differentiation was found between these groups, allowing us to make some biodemographic and historical inferences about the origin and evolution of this geographically isolated island population. Our data are consistent with equivalent and recent contributions from Amerindian and European migrants to the 1900s Rapanui population, with an accelerated increase in the European gene flow during the 20th century, especially since the 1960s. Comparative analysis of our results with other available Alu variation data on neighbouring populations supports the “Voyaging Corridor” model of Polynesian human settlement, which indicates that pre-Polynesians are mainly derived from Southeast Asian and Wallacean populations rather than from Taiwan or the Philippines. This study underlines the importance of sampling and taking into account historical information in genetic studies to unravel the recent evolution of human populations.

Apolipoprotein LPA, APOE, APOC1, and APOC2 genotype frequencies have been determined for the first time in a North African population. A sample of 140 Berber individuals from the Moroccan Moyen Atlas region has been analyzed. Allelic and haplotypic data have been used to compare our sample with other world populations and the results clearly differentiate Berbers from Europeans and Sub-Saharans, suggesting several distinctive features of Moroccan Berbers as the extreme high values of LPA PNR*11 pentanucleotide allele (10.5%) and the relatively high and low values of APOE*E4 (15.7%) and *E2 (4.5%) in comparison to other Mediterraneans. Another remarkable result is the frequency distribution of the two APOC2 alleles (70% vs 30%) in comparison with the European pattern (50% of each allele). The high values of APOE*E4 and LPA PNR*7 together with the intermediate linkage disequilibrium values between APOE and APOC1 alleles in comparison with Europeans and Africans suggest a certain degree of Sub-Saharan influence in the current Moroccan population.

The effect of the C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene, traditionally associated with ischaemic heart disease (IHD), was assessed in a Spanish population. The transmission disequilibrium test (TDT) was used to determine a possible association in a sample of 101 trios of IHD patients. The distribution of MTHFR genotypes was similar in the IHD subjects and the parental group; the TT genotype was present in 14.9% of IHD patients, as compared to 15.2% in the parents. The frequency of the T allele was also similar in IHD cases and parents (39.6% vs. 42.4%; p = 0.649). The TDT confirmed that the observed transmission of the T allele did not deviate significantly from the expected one (chi2 = 0.743; p > 0.4). Our TDT analysis clearly demonstrates a lack of association between the T allele of the C677T mutation in MTHFR and cardiovascular artery disease, both for the general group and for different risk subgroups (smokers, hypertension, male sex, overweight and type A behaviour pattern) in the Spanish population.

Through the nitric oxide (NO) production in the vascular system, the endothelial nitric oxide synthase (eNOS or NOS3) is a key enzyme in blood pressure regulation and atherosclerosis control. Several previous studies have suggested an important role of eNOS as a genetic risk factor for cardiovascular diseases. In this context, a genetic association study was carried out between two eNOS polymorphisms (the ecNOS4a/b VNTR and the G894T substitution) in a sample of 101 nuclear families having one affected offspring of ischemic heart disease (IHD). Transmission disequilibrium test (TDT) revealed partial associations between the VNTR marker and IHD in patients with a type A behavior pattern (TABP) (P = 0.0325, RR = 3.67) and for the haplotype formed by variant b of the VNTR and the T mutation of the G894T substitution in the IHD-affected subgroup having body mass index (BMI) lower than 25 (P = 0.0348, RR = 0.22). However, once multiple testing correction was applied, the associations became nonsignificant. A significant effect of the haplotype b-G increasing high-density lipoprotein cholesterol (HDL-C) plasma levels was detected (P = 0.021 after Bonferroni correction). From a population point of view, frequencies found for G894T substitution in Spain were significantly different from other populations.

Apolipoprotein E (apoE) gene polymorphism was analyzed by polymerase chain reaction in one Moroccan and six Spanish populations, a total of 660 individuals. No significant differences were observed between samples, and the mean relative frequencies (with 95% confidence intervals) found were 0.104 (0.069-0.139) for the epsilon4 allele, 0.855 (0.813-0.897) for epsilon3 and 0.041 (0.015-0.067) for epsilon2. Frequencies of the epsilon4 allele were low in comparison to Northern European populations, but similar to those reported for other South-European populations. The presence of a rare mutation, E2 Christchurch, in one Basque individual was confirmed by sequence analysis.

Data on six protein polymorphisms (19 alleles) from the human population of Tenerife are presented and discussed along with other classical markers in relation to the origin of the Canarians. Genetic influences from three population groups were considered: the Iberians, and the Berbers and non-Berbers (Arabs) from north Africa. The systems examined show the Tenerife population lies within the limits of variation described for various Iberian groups, with a slight tendency towards the characteristics of north African populations. When blood groups, red cell enzymes and serum protein data were considered, the similarity of the Canary population to Iberians seems strengthened (70% estimated contribution of Iberian peninsula genes to the present-day Canarian pool), while some relation with north African groups is shown. Genetic distances between Canarians and Arabs and Canarians and Berbers are lower than those between the two north African groups, indicating a relative and comparable contribution of each to the present-day gene pool of the Canarian population. The Arab contribution could be attributable to the slaves who were introduced to these islands after the conquest in the 15th century, while the Berber contribution could be the remnants of the extinct aboriginal peoples of the islands (Guanches) or a more recent immigration due to slavery. Genetic data do not allow us to distinguish between these two possibilities.

An interesting aspect of the island of Sardinia (Italy) is the wide range of genetic variability within the island itself. The variability is widened by the presence of some populations of different ethnic origin who speak a language other than Sardinian. This work deals with the study of the genetic structure of the Carloforte population which inhabits the tiny island of S. Pietro 4 km off the southwest coast of Sardinia. S. Pietro was first populated in 1738 by emigrants coming from the island of Tabarka (Tunisia) who spoke an archaic form of the Ligurian dialect. Data on genetic polymorphisms in the Carloforte population are presented and discussed in relation to some Sardinian and Italian populations. Data on demographic and matrimonial structure are also presented. The genetic analyses show the Carloforte population as being clearly separated from both Sardinians and continental Italians. The isolation of Carloforte, highlighted by language diversity, endogamy, and consanguinity levels and marriage area, supports the idea of genetic diversity linked to cultural peculiarity.