Transitions in development - an interview with Ariel Waisman.

Ariel Waisman is a CONICET Junior Researcher in the Laboratory of Applied Research in Neurosciences at FLENI in Buenos Aires, Argentina. Ariel's group studies gene regulatory networks in human pluripotent stem cells to address mechanisms of development and cardiac differentiation, among other topics. We spoke to Ariel over Teams to learn more about his career path, the research interests in his group, and the challenges faced by researchers in Argentina and the Global South.

A Triassic stem lepidosaur illuminates the origin of lizard-like reptiles.

The early evolution of diapsid reptiles is marked by a deep contrast between our knowledge of the origin and early evolution of archosauromorphs (crocodiles, avian and non-avian dinosaurs) to that of lepidosauromorphs (squamates (lizards, snakes) and sphenodontians (tuataras)). Whereas the former include hundreds of fossil species across various lineages during the Triassic period1, the latter are represented by an extremely patchy early fossil record comprising only a handful of fragmentary fossils, most of which have uncertain phylogenetic affinities and are confined to Europe1-3. Here we report the discovery of a three-dimensionally preserved reptile skull, assigned as Taytalura alcoberi gen. et sp. nov., from the Late Triassic epoch of Argentina that is robustly inferred phylogenetically as the earliest evolving lepidosauromorph, using various data types and optimality criteria. Micro-computed tomography scans of this skull reveal details about the origin of the lepidosaurian skull from early diapsids, suggesting that several traits traditionally associated with sphenodontians in fact originated much earlier in lepidosauromorph evolution. Taytalura suggests that the strongly evolutionarily conserved skull architecture of sphenodontians represents the plesiomorphic condition for all lepidosaurs, that stem and crown lepidosaurs were contemporaries for at least ten million years during the Triassic, and that early lepidosauromorphs had a much broader geographical distribution than has previously been thought.

A devastating blow: personal reflections on Argentina's scientific decline.

As an Argentine scientist, the defunding of CONICET and INTA feels like a blow to progress and our future. Despite free education, these cuts force talented researchers to seek opportunities abroad. Argentina's history of scientific achievement, from Nobel Prizes to COVID-19 vaccines, is at risk. Defunding science weakens our ability to solve problems and compete globally.

Behavioural Thermoregulation of Flowers via Petal Movement.

Widely documented in animals, behavioural thermoregulation mitigates negative impacts of climate change. Plants experience especially strong thermal variability but evidence for plant behavioural thermoregulation is limited. Along a montane elevation gradient, Argentina anserina flowers warm more in alpine populations than at lower elevation. We linked floral temperature with phenotypes to identify warming mechanisms and documented petal movement and pollinator visitation using time-lapse cameras. High elevation flowers were more cupped, focused light deeper within flowers and were more responsive to air temperature than low; cupping when cold and flattening when warm. At high elevation, a 20° increase in petal angle resulted in a 0.46°C increase in warming. Warming increased pollinator visitation, especially under cooler high elevation temperatures. A plasticity study revealed constitutive elevational differences in petal cupping and stronger temperature-induced floral plasticity in high elevation populations. Thus, plant populations have evolved different behavioural responses to temperature driving differences in thermoregulatory capacity.

Enterocytozoon bieneusi Infection after Hematopoietic Stem Cell Transplant in Child, Argentina.

We report a case of Enterocytozoon bieneusi infection in a pediatric hematopoietic stem cell transplant recipient in Argentina. Spores were visualized in feces using Calcofluor White and modified trichrome stainings. PCR and sequencing identified E. bieneusi genotype D in fecal samples and liver samples, confirming extraintestinal dissemination of the parasite.

Highly Pathogenic Avian Influenza A(H5N1) Viruses from Multispecies Outbreak, Argentina, August 2023.

We report full-genome characterization of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus from an outbreak among sea lions (August 2023) in Argentina and possible spillover to fur seals and terns. Mammalian adaptation mutations in virus isolated from marine mammals and a human in Chile were detected in mammalian and avian hosts.

Molecular Epidemiology of Western Equine Encephalitis Virus, South America, 2023-2024.

Western equine encephalitis virus (WEEV) is a mosquitoborne virus that reemerged in December 2023 in Argentina and Uruguay, causing a major outbreak. We investigated the outbreak using epidemiologic, entomological, and genomic analyses, focusing on WEEV circulation near the Argentina‒Uruguay border in Rio Grande do Sul state, Brazil. During November 2023‒April 2024, the outbreak in Argentina and Uruguay resulted in 217 human cases, 12 of which were fatal, and 2,548 equine cases. We determined cases on the basis of laboratory and clinical epidemiologic criteria. We characterized 3 fatal equine cases caused by a novel WEEV lineage identified through a nearly complete coding sequence analysis, which we propose as lineage C. Our findings highlight the importance of continued surveillance and equine vaccination to control future WEEV outbreaks in South America.

Orthohantaviruses in Misiones Province, Northeastern Argentina.

Few cases of hantavirus pulmonary syndrome have been reported in northeastern Argentina. However, neighboring areas show a higher incidence, suggesting underreporting. We evaluated the presence of antibodies against orthohantavirus in small rodents throughout Misiones province. Infected Akodon affinis montensis and Oligoryzomys nigripes native rodents were found in protected areas of Misiones.

5th Argentinean Meeting on Evolutionary Biology (RABE V): Report on the "Evo-Devo" Extended Symposium.

Evolutionary developmental biology (Evo-Devo) is flourishing in Latin America, particularly Argentina, where researchers are leveraging this integrative field to unlock the secrets of the region's remarkable biodiversity. A recent symposium held at the 5th Argentinean Meeting on Evolutionary Biology (RABE V) showcased a vibrant Evo-Devo community and the diversity of its research endeavors. The symposium included 3 plenary talks, 3 short talks, and 12 posters, and spanned a range of organisms and approaches. Interestingly, the symposium highlighted a prevalence of "top-down" Evo-Devo studies in the region, where researchers first analyze existing diversity and then propose potential developmental mechanisms. This approach, driven in part by financial constraints and the region's historical focus on natural history, presents a unique opportunity to bridge disciplines like comparative biology, paleontology, and botany. The symposium's success underscores the vital role of Evo-Devo in Latin America, not only for advancing our understanding of evolution but also for providing valuable tools to conserve and manage the region's irreplaceable biodiversity. As Evo-Devo continues to grow in Latin America, fostering collaboration and knowledge exchange within the region and beyond will be crucial for realizing the full potential of this transformative field.

Telemedicine in HIV health care during the COVID-19 pandemic: An implementation research study in Buenos Aires, Argentina.

BACKGROUND: From October 2020 to October 2022, we conducted an implementation study to offer telemedicine (TM) across four HIV units of general public hospitals in Buenos Aires. The intervention used TM to provide a continuum of care to patients with HIV. METHODS AND SETTING: We used the RE-AIM framework to evaluate the strategy. The study started during a COVID-19 outbreak with strict lockdown policies and continued until return to normal practices. Implementation facilitation served as the core implementation strategy. RESULTS: We reached 4118 patients (58% of eligible individuals), and the main perceived benefits were the ability to avoid exposure to infectious diseases and reduced travel time and cost. After a median of 515 days of follow-up, 95.7% of participants with HIV were receiving antiretroviral therapy, and 87.8% were virally suppressed, with a median CD4+ count of 648 cells/µL. In total, 36.6% reported clinical events, and 20.4% presented with COVID-19 infection. The proportion of physicians adopting TM was 69.37%. After enrolment, 2406 of 5640 (43%) follow-up visits were conducted via TM. By the end of the study, 26.29% of appointments offered in the four centres were through TM, whereas 73.71% were in-person appointments. CONCLUSION: It was feasible to implement TM in the four centres in the public health sector in Buenos Aires, Argentina. It was acceptable for both patients and healthcare workers, and effectively reached a large proportion of the population served in these clinics. Both healthcare workers and patients consider it a model of care that will continue to be offered in the future.

Haemovigilance survey and screening strategy for arthropod-borne viruses in blood donors from Argentina.

Arthropod-borne viruses (arboviruses) count among emerging infections, which represent a major challenge for transfusion safety worldwide. To assess the risk of arboviruses-transmission by transfusion (ATT), we performed a survey to evaluate the potential threat for transfusion safety. Samples were retrospectively and randomly collected from donors who donated during the peak of dengue incidence in Cordoba (years: 2016 and 2019-2022). A cost-efficient strategy for molecular screening was implemented with a nucleic acid test (NAT) configured with Flavivirus and Alphavirus-universal degenerated primers targeting conserved gene regions. Besides, we evaluated the neutralizing antibody (NAb) prevalence by plaque reduction neutralization test (PRNT). A total of 1438 samples were collected. Among the NAT-screened samples, one resulted positive for Flavivirus detection. Subsequent sequencing of the PCR product revealed Saint Louis Encephalitis Virus (SLEV) infection (GeneBank accession number OR236721). NAb prevalence was 2.95% for anti-Dengue, 9.94% anti-SLEV, 1.09% anti-West Nile Virus, and 0% anti-Chikungunya. One of the NAb-positive samples also resulted positive for IgM against SLEV but negative by ARN detection. This is the first haemovigilance study developed in Argentina that evaluates the potential risk of ATT and the first research to determine the prevalence of NAb against Flavivirus through PNRT to avoid possible cross-reactions between Ab against Flavivirus. Herein, the finding of one SLEV-viremic donor and the detection of anti-SLEV IgM in a different donor demonstrated a potential threat for transfusion safety and emphasized the need for increased vigilance and proactive measures to ensure the safety of blood supplies.

Introgression from local cultivars is a driver of agricultural adaptation in Argentinian weedy rice.

Weedy rice, a pervasive and troublesome weed found across the globe, has often evolved through fertilization of rice cultivars with little importance of crop-weed gene flow. In Argentina, weedy rice has been reported as an important constraint since the early 1970s, and, in the last few years, strains with herbicide-resistance are suspected to evolve. Despite their importance, the origin and genetic composition of Argentinian weedy rice as well its adaptation to agricultural environments has not been explored so far. To study this, we conducted genotyping-by-sequencing on samples of Argentinian weedy and cultivated rice and compared them with published data from weedy, cultivated and wild rice accessions distributed worldwide. In addition, we conducted a phenotypic characterization for weedy-related traits, a herbicide resistance screening and genotyped accessions for known mutations in the acetolactate synthase (ALS) gene, which confers herbicide resistance. Our results revealed large phenotypic variability in Argentinian weedy rice. Most strains were resistant to ALS-inhibiting herbicides with a high frequency of the ALS mutation (A122T) present in Argentinian rice cultivars. Argentinian cultivars belonged to the three major genetic groups of rice: japonica, indica and aus while weeds were mostly aus or aus-indica admixed, resembling weedy rice strains from the Southern Cone region. Phylogenetic analysis supports a single origin for aus-like South American weeds, likely as seed contaminants from the United States, and then admixture with local indica cultivars. Our findings demonstrate that crop to weed introgression can facilitate rapid adaptation to agriculture environments.

Plastid phylogenomics of the tribe potentilleae (Rosaceae).

The tribe Potentilleae comprises approximately 1700 species in 13 genera, making it one of the largest of the 16 tribes in Rosaceae. Our understanding of the composition and relationships among members of Potentilleae has advanced dramatically with the application of molecular markers in the last two decades. Yet there is still much work remaining toward a robust phylogenetic framework for the entire Potentilleae and a comprehensive genus-level dating framework for the tribe. The goals of the present study were to establish a phylogenetic framework for Potentilleae, infer the origin and diversification of the tribe using a temporal framework, and explore the taxonomic implications in light of the updated phylogenetic framework. We used the plastome sequences from 158 accessions representing 139 taxa covering all 13 recognized genera of the tribe to reconstruct the Potentilleae phylogeny. High phylogenetic resolution was recovered along the Potentilleae backbone. Two major clades were recovered within Potentilleae, corresponding to the two subtribes Fragariinae and Potentillinae. Within Fragariinae, two subclades were recovered. In one subclade, Sibbaldia sensu stricto is sister to a clade containing Sibbaldianthe, Comarum, Farinopsis, and Alchemilla sensu lato. In the other subclade, Fragaria is sister to a clade comprising Chamaerhodos, Chamaecallis, Drymocallis, Dasiphora, and Potaninia. Within Potentillinae, Argentina is sister to Potentilla sensu stricto. Within Potentilla sensu stricto, clade Himalaya is sister to Alba, and the Himalaya-Alba clade together is sister to a clade comprising Reptans, Potentilla ancistrifolia Bunge, Fragarioides, Ivesioid, and Argentea. Divergence time estimates indicated that tribe Potentilleae originated during the middle Eocene, and subtribes Fragariinae and Potentillinae diverged around the Eocene-Oligocene transition, and divergence times dated for Potentilleae genera ranged from the early Miocene to the late Pleistocene.

Implementation of WHO guidelines for cervical cancer screening, diagnosis and treatment: knowledge and perceptions of health providers from Argentina.

BACKGROUND: The 2021 World Health Organization (WHO) guidelines on cervical cancer screening and treatment provide countries with evidence-based recommendations to accelerate disease elimination. However, evidence shows that health providers' adherence to screening guidelines is low. We conducted a study in Argentina to analyze health providers' knowledge and perceptions regarding the 2021 WHO Guidelines. METHODS: A qualitative study was conducted based on individual, semi-structured interviews with health providers specializing in gynecology (n = 15). The themes explored were selected and analyzed using domains and constructs of the Consolidated Framework for Implementation Research. RESULTS: Although health providers perceive WHO as a reliable institution, they do not know the 2021 guidelines, its supporting evidence, and its elaboration process. Their clinical practice is mainly guided by local recommendations developed by national professional medical associations (PMAs). For interviewees, WHO guidelines should be disseminated through health authorities and national PMAs, mainly through in-service training. Health providers had a positive assessment regarding WHO Recommendation 1 (screen, triage, and treatment for women aged 30 + with HPV-testing every 5 to 10 years) and perceived a favorable climate for its implementation. HPV-testing followed by triage was considered a low-complexity practice, enabling a better detection of HPV, a better selection of the patients who will need diagnosis and treatment, and a more efficient use of health system resources. However, they suggested adapting this recommendation by removing screening interval beyond 5 years. WHO Recommendation 2 (screen-and-treat approach with HPV-testing for women aged 30 + every 5 to 10 years) was predominantly rejected by interviewees, was considered an algorithm that did not respond to women's needs, and was not adequate for the Argentinean context. Regarding the HPV-test modality, clinician-collected tests were the preferred mode. Health providers considered that HPV self-collection should be used primarily among socially vulnerable women to increase screening coverage. CONCLUSION: WHO guidelines should be widely disseminated among health providers, especially in settings that could benefit from a screen-and-treat approach. Identifying areas of partnership and collaboration with PMAs in implementing WHO guidelines is essential.

Sex and Socioeconomic Disparities in Dementia Risk: A Population-Attributable Fraction Analysis in Argentina.

INTRODUCTION: Twelve modifiable risk factors (RFs) account for 40% of dementia cases worldwide. However, limited data exist on such factors in middle- and low-income countries. We aimed to estimate the population-attributable fractions (PAFs) for the 12 RFs in Argentina, assessing changes over a decade and exploring socioeconomic and sex influences. METHODS: We conducted cross-sectional analyses of the 12 RFs from Argentinian surveys conducted in 2009, 2015, and 2018, including 96,321 people. We calculated PAFs and stratified estimates based on sex and income. RESULTS: We estimated an overall PAF of 59.6% (95% CI = 58.9-60.3%). The largest PAFs were hypertension = 9.3% (8.7-9.9%), physical inactivity = 7.4% (6.8-8.2%), and obesity = 7.4% (6.8-7.9%). Men were more impacted by excessive alcohol, while women by isolation and smoking. Lower income linked to higher PAFs in education, hypertension, and obesity. DISCUSSION: Argentina has a higher PAF for dementia than the world population, with distinct RF distribution. PAF varied by sex and economic status, advocating tailored prevention strategies.

Results and prognosis of kidney transplantation in lupus nephritis: Experience of an Argentine center.

INTRODUCTION: Although RT has improved the survival of the population with ESRD due to all causes, renal outcomes in SLE are controversial. The objective of this study is to describe the characteristics and evolution of the patients and the kidney transplant in LN, and compare it with patients transplanted for other causes. MATERIALS AND METHODS: Retrospective, observational, analytical, single-center study in which records of patients undergoing nephrotransplantation for LN were analyzed. They were compared with a group of patients transplanted at the same center for other causes of ESRD. RESULTS: 41 patients with kidney transplant due to SLE and 89 transplanted due to other causes of ESRD were registered. Graft loss occurred in 12 (29.26%) patients with LN and 34 (38.2%) patients in the comparison group (p = .428). Only one case (4.8%) presented reactivation of the LN in the graft, without graft loss. Median graft survival was 73.1 months in the LN group and 66.3 months in the comparison group (p = .221). A total of 8 (19.5%) patients with LN and 11 (12.4%) without LN died (p = .42), with infections being the main cause in both groups. There were no statistically significant differences between groups in graft and patient survival. In a sub-analysis of 28 patients with LN with aPL study, 4 thrombotic events were observed, in 3 different patients, in the aPL-positive group. There were no statistically significant differences in terms of causes of graft loss and graft survival (positive aFL 75.7 months vs negative aFL 72.7 months, p= .96). There were also no differences in mortality between the groups (p = .61). CONCLUSION: Patients transplanted for LN did not differ from the control population in terms of graft and patient survival. Infections were the main cause of death, so prophylaxis and vaccination continue to be a fundamental pillar in the prevention of infections in immunocompromised patients.

A new abelisaurid dinosaur from the end Cretaceous of Patagonia and evolutionary rates among the Ceratosauria.

Gondwanan dinosaur faunae during the 20 Myr preceding the Cretaceous-Palaeogene (K/Pg) extinction included several lineages that were absent or poorly represented in Laurasian landmasses. Among these, the South American fossil record contains diverse abelisaurids, arguably the most successful groups of carnivorous dinosaurs from Gondwana in the Cretaceous, reaching their highest diversity towards the end of this period. Here we describe Koleken inakayali gen. et sp. n., a new abelisaurid from the La Colonia Formation (Maastrichtian, Upper Cretaceous) of Patagonia. Koleken inakayali is known from several skull bones, an almost complete dorsal series, complete sacrum, several caudal vertebrae, pelvic girdle and almost complete hind limbs. The new abelisaurid shows a unique set of features in the skull and several anatomical differences from Carnotaurus sastrei (the only other abelisaurid known from the La Colonia Formation). Koleken inakayali is retrieved as a brachyrostran abelisaurid, clustered with other South American abelisaurids from the latest Cretaceous (Campanian-Maastrichtian), such as Aucasaurus, Niebla and Carnotaurus. Leveraging our phylogeny estimates, we explore rates of morphological evolution across ceratosaurian lineages, finding them to be particularly high for elaphrosaurine noasaurids and around the base of Abelisauridae, before the Early Cretaceous radiation of the latter clade. The Noasauridae and their sister clade show contrasting patterns of morphological evolution, with noasaurids undergoing an early phase of accelerated evolution of the axial and hind limb skeleton in the Jurassic, and the abelisaurids exhibiting sustained high rates of cranial evolution during the Early Cretaceous. These results provide much needed context for the evolutionary dynamics of ceratosaurian theropods, contributing to broader understanding of macroevolutionary patterns across dinosaurs.