Ancient DNA Analysis Suggests Negligible Impact of the Wari Empire Expansion in Peru's Central Coast during the Middle Horizon.

The analysis of ancient human DNA from South America allows the exploration of pre-Columbian population history through time and to directly test hypotheses about cultural and demographic evolution. The Middle Horizon (650-1100 AD) represents a major transitional period in the Central Andes, which is associated with the development and expansion of ancient Andean empires such as Wari and Tiwanaku. These empires facilitated a series of interregional interactions and socio-political changes, which likely played an important role in shaping the region's demographic and cultural profiles. We analyzed individuals from three successive pre-Columbian cultures present at the Huaca Pucllana archaeological site in Lima, Peru: Lima (Early Intermediate Period, 500-700 AD), Wari (Middle Horizon, 800-1000 AD) and Ychsma (Late Intermediate Period, 1000-1450 AD). We sequenced 34 complete mitochondrial genomes to investigate the potential genetic impact of the Wari Empire in the Central Coast of Peru. The results indicate that genetic diversity shifted only slightly through time, ruling out a complete population discontinuity or replacement driven by the Wari imperialist hegemony, at least in the region around present-day Lima. However, we caution that the very subtle genetic contribution of Wari imperialism at the particular Huaca Pucllana archaeological site might not be representative for the entire Wari territory in the Peruvian Central Coast.

Ancient mitochondrial DNA provides high-resolution time scale of the peopling of the Americas.

The exact timing, route, and process of the initial peopling of the Americas remains uncertain despite much research. Archaeological evidence indicates the presence of humans as far as southern Chile by 14.6 thousand years ago (ka), shortly after the Pleistocene ice sheets blocking access from eastern Beringia began to retreat. Genetic estimates of the timing and route of entry have been constrained by the lack of suitable calibration points and low genetic diversity of Native Americans. We sequenced 92 whole mitochondrial genomes from pre-Columbian South American skeletons dating from 8.6 to 0.5 ka, allowing a detailed, temporally calibrated reconstruction of the peopling of the Americas in a Bayesian coalescent analysis. The data suggest that a small population entered the Americas via a coastal route around 16.0 ka, following previous isolation in eastern Beringia for ~2.4 to 9 thousand years after separation from eastern Siberian populations. Following a rapid movement throughout the Americas, limited gene flow in South America resulted in a marked phylogeographic structure of populations, which persisted through time. All of the ancient mitochondrial lineages detected in this study were absent from modern data sets, suggesting a high extinction rate. To investigate this further, we applied a novel principal components multiple logistic regression test to Bayesian serial coalescent simulations. The analysis supported a scenario in which European colonization caused a substantial loss of pre-Columbian lineages.

AmericaPlex26: a SNaPshot multiplex system for genotyping the main human mitochondrial founder lineages of the Americas.

Phylogeographic studies have described a reduced genetic diversity in Native American populations, indicative of one or more bottleneck events during the peopling and prehistory of the Americas. Classical sequencing approaches targeting the mitochondrial diversity have reported the presence of five major haplogroups, namely A, B, C, D and X, whereas the advent of complete mitochondrial genome sequencing has recently refined the number of founder lineages within the given diversity to 15 sub-haplogroups. We developed and optimized a SNaPshot assay to study the mitochondrial diversity in pre-Columbian Native American populations by simultaneous typing of 26 single nucleotide polymorphisms (SNPs) characterising Native American sub-haplogroups. Our assay proved to be highly sensitive with respect to starting concentrations of target DNA and could be applied successfully to a range of ancient human skeletal material from South America from various time periods. The AmericaPlex26 is a powerful assay with enhanced phylogenetic resolution that allows time- and cost-efficient mitochondrial DNA sub-typing from valuable ancient specimens. It can be applied in addition or alternative to standard sequencing of the D-loop region in forensics, ancestry testing, and population studies, or where full-resolution mitochondrial genome sequencing is not feasible.

Ureaplasmas and mycoplasmas in vaginal samples from prepubertal girls and the reasons for gynecological consultation.

OBJECTIVES: The aim of the study was to evaluate vaginal colonization with Ureaplasmaurealyticum (UU) and Mycoplasma hominis (MH) in prepubertal girls and reason for gynecological consultation. PATIENTS AND METHODS: All prepubertal girls sent for consultation for medical issues to a pediatric gynecology department. Vaginal swabs were obtained for culture and were seeded using specific media. Patients colonized with genital mycoplasmas (GMs) were evaluated by a psychologist to rule out sexual abuse (SA). RESULTS: A total of119 patients were included. The mean age was 5.9 y. Reasons for consultation were vulvovaginitis in 78 (66%), SA before study entry in 19 (16%), labial adhesion in 8 (7%), genital bleeding in 8 (7%), suspected sexual abuse in 3 (3%) and 1 patient was sent for consultation for labial adhesion but had a normal examination (1%), physical neglect in 1 (1%), and genital ulcers in 1 (1%). UU was isolated in 14 (12%) MH was isolated in 3 (3%). UU was isolated in 9 patents (47%) with SA before study entry. Five patients colonized with UU that had consulted for other reasons were evaluated by a pediatric psychologist; 4 disclosed SA. One patient colonized with UU did not disclose SA. Patients with GMs were more likely to disclose sexual abuse (UU P < .0001. MH P < .0065). CONCLUSION: GMs were isolated more in SA cases. Patients colonized with GMs and consulted for other issues than SA were more likely to disclose SA.

[Illicit and psychotropic drug use among medical students at the Pontificia Universidad Católica de Chile]. / Consumo de sustancias ilícitas y psicotrópicos entre los estudiantes de medicina de la Pontificia Universidad Católica de Chile.

BACKGROUND: Illicit drug abuse is a public health problem, generally starting in adolescence. Medical students are not an exception. AIM: To assess the consumption of illicit drugs among medical students of the Pontificia Universidad Católica de Chile. MATERIAL AND METHODS: A questionnaire used by the National Council for the Control of Substance Abuse (CONACE) to evaluate substance use and the Goldberg Health Questionnaire (GHQ-12), were applied to medical students. The questionnaires were self administered under supervision. RESULTS: The survey was completed by 569 of 775 students (74%). "Ever used" reached 33% for marijuana, 1.196 for cocaine, 2.1% for amphetamines without prescription, 6.9% for not prescribed benzodiazepines and 5.8% for not prescribed antidepressants. The use of these substances was only associated for ever used marijuana and level of career (p <0.01), with the highest rate in the seventh final year (51.4%). Benzodiazepine use was also associated with the level of career (p <0.01) with less than 6% prevalence from first to fourth and the highest in seventh year (32.4%). Non prescribed antidepressant use was significantly higher among women. Tobacco and alcohol use were associated with consumption of marijuana (p <0.0001) and benzodiazepines (p <0.0001). CONCLUSIONS: Our medical students have low marijuana consumption rates, only above Turkey. Cocaine and amphetamines use is low, benzodiazepine consumption is higher among final year students. Antidepressant use is higher among women.

[Smoking and alcohol drinking among medical students at the Pontificia Universidad Católica de Chile]. / Consumo de tabaco y alcohol entre los estudiantes de medicina de la Pontificia Universidad Católica de Chile.

BACKGROUND: Tobacco and alcohol consumption are public health problems, generally starting in adolescence. Medical students are not an exception. AIM: To determine the characteristics of tobacco and alcohol use among medical students at the Pontificia Universidad Católica de Chile and their association with gender, career level and mental health. MATERIAL AND METHODS: A questionnaire to evaluate substance use was applied along with Goldberg Health Questionnaire (GHQ-12), as a mental health risk predictor, to all medical students in November 2005. RESULTS: The survey was completed by 569 of 775 students (74%). Current smokers were 23- 7%, with the lowest figure, 13-5% in sixth year, and the highest, 40.5% in seventh year (p <0.01). Thirty one percent of students with an score of five and over in the GHQ-12 were smokers, compared to 19% among those with a lower score. Daily smokers were 40%o of the current smokers. Seventy four percent of students consumed alcohol during the last month. No association with sex or GHQ-12 was observed. The lowest alcohol consumption rate was observed in second year, and the highest in sixth year (66%o and 89-2%o, respectively, p <0.01). Fifty three percent of men and 26%o of women drank three or more drinks in any given day (p <0.01). Sixty three percent of men and 81% of women never drank more than five drinks in one day, during the last month (p <0.01). CONCLUSIONS: Our medical students smoke less than Chilean youth but more than medical students of countries such as the USA. They drink less than Anglo-Saxon medical students but more than Chilean youth. Male consumption is greater than that of women. Smoking and alcohol drinking are mutually associated.

Consumo de sustancias ilícitas y psicotrópicos entre los estudiantes de medicina de la Pontificia Universidad Católica de Chile / Illicit and psychotropic drug use among medical students at the Pontificia Universidad Católica de Chile

Background: Illicit drug abuse is a public health problem, generally starting in adolescence. Medical students are not an exception. Aim: To assess the consumption of illicit drugs among medical students of the Pontificia Universidad Católica de Chile. Material and Methods: A questionnaire used by the National Council for the Control of Substance Abuse (CONACE) to evaluate substance use and the Goldberg Health Questionnaire (GHQ-12), were applied to medical students. The questionnaires were self administered under supervision. Results: The survey was completed by 569 of 775 students (74%). “Ever used” reached 33% for marijuana, 1.1% for cocaine, 2.1% for amphetamines without prescription, 6.9% for not prescribed benzodiazepines and 5.8% for not prescribed antidepressants. The use of these substances was only associated for ever used marijuana and level of career (p <0.01), with the highest rate in the seventh final year (51.4%). Benzodiazepine use was also associated with the level of career (p <0.01) withless than 6% prevalence from first to fourth and the highest in seventh year (32.4%). Non prescribed antidepessant use was significantly higher among women. Tobacco and alcohol use were associated with consumption of marijuana (p <0.0001) and benzodiazepines (p <0.0001). Conclusions: Our medical students have low marijuana consumption rates, only above Turkey. Cocaine and amphetamines use is low, benzodiazepine consumption is higher among final year students. Antidepressant use is higher among women.

Consumo de tabaco y alcohol entre los estudiantes de medicina de la Pontificia Universidad Católica de Chile / Smoking and alcohol drinking among medical students at the Pontificia Universidad Católica de Chile

Background: Tobacco and alcohol consumption are public health problems, generally starting in adolescence. Medical students are not an exception. Aim: To determine the characteristics of tobacco and alcohol use among medical students at the Pontificia Universidad Católica de Chile and their association with gender, career level and mental health. Material and methods: A questionnaire to evaluate substance use was applied along with Goldberg Health Questionnaire (GHQ-12), as a mental health risk predictor, to all medical students in November 2005- Results: The survey was completed by 569 of 775 students (74 percent). Current smokers were 23- 7 percent, with the lowest figure, 13-5 percent in sixth year, and the highest, 40.5 percent in seventh year (p <0.01). Thirty one percent of students with an score of five and over in the GHQ-12 were smokers, compared to 19 percent among those with a lower score. Daily smokers were 40 percento of the current smokers. Seventy four percent of students consumed alcohol during the last month. No association with sex or GHQ-12 was observed. The lowest alcohol consumption rate was observed in second year, and the highest in sixth year (66 percento and 89-2 percento, respectively, p <0.01). Fifty three percent of men and 26 percento of women drank three or more drinks in any given day (p <0.01). Sixty three percent of men and 81 percent of women never drank more than five drinks in one day, during the last month (p <0.01). Conclusions: Our medical students smoke less than Chilean youth but more than medical students of countries such as the USA. They drink less than Anglo-Saxon medical students but more than Chilean youth. Male consumption is greater than that of women. Smoking and alcohol drinking are mutually associated.

Reducing infant mortality in Chile: success in two phases.

Latin America, and especially Chile, has done well in reducing infant mortality, with rates of around twenty-five per thousand live births. There are two clear phases of declining mortality: one largely influenced by poverty reduction, primary health care, and environmental and demographic factors; and a second one more sensitive to focused health care interventions. In 2000 Chile reached 8.9 infant deaths per 1,000, using interventions that represent an increase in the provision of services related to perinatal risks, acute respiratory diseases, congenital heart conditions, and certain vaccine-preventable infections. Chile, with per capita income near 5,000 US dollars in 2000, has infant mortality that compares with that of wealthier countries.