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Considering that their distribution is limited to altitudinal gradients along mountains that are likely to become warmer and drier, climate change poses an increased threat to temperate forest species from tropical regions. We studied whether the understorey shrub Lupinus elegans, endemic to temperate forests of west-central Mexico, will be able to withstand the projected temperature increase under seven climate change scenarios. Seeds were collected along an altitudinal gradient and grown in a shade-house over 7 months before determining their temperature tolerance as electrolyte leakage. The plants from colder sites tolerated lower temperatures, i.e. the temperature at which half of the maximum electrolyte leakage occurred ( LT50), ranged from −6.4 ± 0.7 to −2.4 ± 0.3 °C. In contrast, no pattern was found for tolerance to high temperature ( LT50 average 42.8 ± 0.3 °C). The climate change scenarios considered here consistently estimated an increase in air temperature during the present century that was higher for the maximum air temperature than for the mean or minimum. In particular, the anomaly from the normal maximum air temperature at the study region ranged from 2.8 °C by 2030 to 5.8 °C by 2090. In this respect, the inability of L. elegans to adapt to increasingly higher temperatures found here, in addition to a possible inhibition of reproduction caused by warmer winters, may limit its future distribution. [ABSTRACT FROM AUTHOR]

Objectives: To test the hypothesis that an inverse association exists between socioeconomic position and all-cause mortality in a developing country in Latin America. Study design: Prospective cohort study carried out in Chile using data from a simple random sample of 920 apparently healthy subjects (weighted population 11,600 aged 30-89 years) followed for 8 years. Methods: Education level (0-8 years, 9-12 years and ≥13 years) and income quartiles were established at the outset of the study, along with behavioural and biological risk factors for chronic diseases: smoking, alcohol use, obesity, diabetes, hypertension, lipids and family history of death by cardiovascular disease. Relative risks of all-cause mortality were estimated using age-adjusted Cox regression models. Results: During the follow-up period, 46 deaths were observed. Adjusting for age, gender, and behavioural and biological risk factors, the mortality risk for increasing categories of education after controlling for income was 1.0, 0.76 and 0.33 (P for trend < 0.01). In contrast, the relative risk for increasing levels of income after controlling for education was 1.0, 0.98, 1.33 and 1.17 (P for trend = 0.07). Conclusion: While education level had a protective effect on mortality risk of Chilean adults, income had a slightly unfavourable effect on survival. This finding is described as suggestive of a 'pauper-rich paradox', since the higher income quantiles in this study correspond with the lower income levels in most developed countries. Nevertheless, due to the small number of deaths, additional research is required to assess the validity of these findings. [ABSTRACT FROM AUTHOR]

Background: Cancer is the fourth leading cause of death in adolescents and young adults (AYA) worldwide. Although successful treatment of cancer in AYA has increased in recent years in most of the world, this is not true for many low- and middle-income countries (LMIC) where over 80% of all AYA live. This study investigated the needs of AYA with cancer in parts of Latin America (LATAM) through the perspectives of non-physician health care providers and partners., Methods: Semi-structured interviews (in Spanish) were conducted with non-physician partners from Mexico, Peru, Central America, and the Caribbean over Zoom. Participants were recruited through previously identified local physicians and international non-physician professionals working in these countries. Transcripts were coded and key themes identified until thematic saturation was reached (Atlas.ti)., Findings: Thirty participants representing eight countries were interviewed, providing 1202 min of transcript data. Data were organized into barriers, facilitators, and strategies to improve the delivery of health care for AYA with cancer in LATAM at the patient- (e.g., financial barriers, continued schooling), parent- (e.g., limited medical literacy, advocacy), and hospital-level (e.g., structural barriers, increasing funding)., Interpretation: There are many similarities in the barriers and facilitators to AYA care between LATAM and high-income countries (HIC); however, some characteristics are more unique to LATAM, for example, strict age restrictions for pediatric care and abandonment of therapy. As LATAM countries continue to build cancer control programs, there is an opportunity to consider our identified barriers, facilitators, and strategies to address the unique needs of AYA with cancer., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Background: HIV-positive patients are underrepresented in clinical trials of metastatic squamous cell carcinoma of the anal canal (mSCCA). We aimed to compare the clinical outcomes of mSCCA patients according to HIV infection., Methods: This was a retrospective multicenter cohort study of consecutive patients with mSCCA. All HIV-positive patients received antiretroviral therapy. The primary endpoint was overall survival (OS), and secondary endpoints were progression-free survival (PFS) and response rate (RR)., Results: From January 2005 to December 2019, 113 patients were included: 20 (17.6%) had HIV infection. HIV-positive patients were younger at diagnosis and more frequently male, and 20% (n = 8) received exclusively best supportive care in comparison with 8.6% of HIV-negative patients (P = .13). Both groups were similar in terms of Eastern Cooperative Oncology Group (ECOG) performance status, pattern of metastatic disease, and type of first-line chemotherapy. Five (25%) HIV-positive and 36 (38.7%) HIV-negative patients received second-line therapies (P = .24). RR and median PFS in first-line were similar between the groups: 35% and 30.1% (P = .78) and 4.9 and 5.3 months (P = .85) for patients with and without HIV infection, respectively. At a median follow-up of 26 months, median OS was 11.3 months (95% confidence interval [CI] 10.1 to 26.4) for HIV-infected patients versus 14.6 months (95% CI 11.1 to 18.1) for HIV-negative patients (P = .92). In the univariate analysis for OS, only ECOG performance status was significant., Conclusion: HIV-positive mSCCA patients under antiretroviral therapy have oncological outcomes similar to those of HIV-negative patients. These patients should be included in trials of mSCCA., Competing Interests: Declaration of Competing Interest None to declare, (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: Latin America bears an important burden of critical care disease, yet the information about it is scarce. Our objective was to describe structure, organization, processes of care, and research activities in Latin-American ICUs., Design: Web-based survey submitted to ICU directors., Settings: ICUs located in nine Latin-American countries., Subjects: Individual ICUs., Interventions: None., Measurements and Main Results: Two hundred fifty-seven of 498 (52%) of submitted surveys responded: 51% from Brazil, 17% Chile, 13% Argentina, 6% Ecuador, 5% Uruguay, 3% Colombia, and 5% between Mexico, Peru, and Paraguay. Seventy-nine percent of participating hospitals had less than 500 beds; most were public (59%) and academic (66%). ICUs were mainly medical-surgical (75%); number of beds was evenly distributed in the entire cohort; 77% had 24/7 intensivists; 46% had a physician-to-patient ratio between 1:4 and 7; and 69% had a nurse-to-patient ratio of 1 ≥ 2.1. The 24/7 presence of other specialists was deficient. Protocols in use averaged 9 ± 3. Brazil (vs the rest) had larger hospitals and ICUs and more quality, surveillance, and prevention committees, but fewer 24/7 intensivists and poorer nurse-to-patient ratio. Although standard monitoring, laboratory, and imaging practices were almost universal, more complex measurements and treatments and portable equipment were scarce after standard working hours, and in public hospitals. Mortality was 17.8%, without differences between countries., Conclusions: This multinational study shows major concerns in the delivery of critical care across Latin America, particularly in human resources. Technology was suboptimal, especially in public hospitals. A 24/7 availability of supporting specialists and of key procedures was inadequate. Mortality was high in comparison to high-income countries.

Admixture occurs when individuals from parental populations that have been isolated for hundreds of generations form a new hybrid population. Currently, interest in measuring biogeographic ancestry has spread from anthropology to forensic sciences, direct-to-consumers personal genomics, and civil rights issues of minorities, and it is critical for genetic epidemiology studies of admixed populations. Markers with highly differentiated frequencies among human populations are informative of ancestry and are called ancestry informative markers (AIMs). For tri-hybrid Latin American populations, ancestry information is required for Africans, Europeans and Native Americans. We developed two multiplex panels of AIMs (for 14 SNPs) to be genotyped by two mini-sequencing reactions, suitable for investigators of medium-small laboratories to estimate admixture of Latin American populations. We tested the performance of these AIMs by comparing results obtained with our 14 AIMs with those obtained using 108 AIMs genotyped in the same individuals, for which DNA samples is available for other investigators. We emphasize that this type of comparison should be made when new admixture/population structure panels are developed. At the population level, our 14 AIMs were useful to estimate European admixture, though they overestimated African admixture and underestimated Native American admixture. Combined with more AIMs, our panel could be used to infer individual admixture. We used our panel to infer the pattern of admixture in two urban populations (Montes Claros and Manhuaçu) of the State of Minas Gerais (southeastern Brazil), obtaining a snapshot of their genetic structure in the context of their demographic history.

"The analysis of probable growth rates among families, based on census figures, proved that fertility rates in Mexico began to fall earlier and less selectively than suggested by previous studies. The first changes in reproductive patterns occurred prior to official family planning programs. A state-by-state probability analysis discovered the existence of three groups of states corresponding to the different stages of changing fertility rates." (SUMMARY IN ENG), (excerpt)

In order to study the efficacy and tolerance of isradipine, a new Ca++ antagonist for the treatment of stable chronic angina, a multicentric cooperative study was carried out in eight Latin American countries (Argentine, Chile, Colombia, Ecuador, Mexico, Peru, Uruguay and Venezuela), which included 169 patients (60% men and 40% women), average age 62.6 +/- 9.7. Patients with more than 4 biweekly anginal crisis were accepted, with one or more of the following inclusion criteria: coronariographic evidence of obstruction greater than 60% in one or more vessels, IAM history, positive scintigraphy and positive effort test. The trial was single-blind, with placebo during the admission phase (2 weeks) and active treatment for 12 weeks. isradipine was administered in increasing doses of 2.5, 5, and 7 mg thrice a day, according to the presence or absence of anginal crisis. It was observed that the average frequency of weekly pains decreased from 8.2 +/- 7 under placebo to 6.3 +/- 7.5 under isradipine at low doses, and to 2.0 +/- 2.0 (p less than 0.001) under maximum doses. TNT intake decreased parallel also in a significant way. At the end of the trial, 37% of patients had become asymptomatic, and angina had reduced to less than two crisis a week in 33%. A clear relation doses-effect was observed. There was no alteration in laboratory exams neither in ECG. Seven patients had complications derived from the evolutional course of disease (2 IAM, 5 unstable angina and one sudden death). Adverse events were relatively frequent and the majority derived from vasodilator effect (tibial oedema 37%, flushing 17%, headache 23%).(ABSTRACT TRUNCATED AT 250 WORDS)