Soluble factors in COVID-19 mRNA vaccine-induced myocarditis causes cardiomyoblast hypertrophy and cell injury: a case report.

BACKGROUND: Inflammation affecting the heart and surrounding tissues is a clinical condition recently reported following COVID-19 mRNA vaccination. Assessing trends of these events related to immunization will improve vaccine safety surveillance and best practices for forthcoming vaccine campaigns. However, the causality is unknown, and the mechanisms associated with cardiac myocarditis are not understood. CASE PRESENTATION: After the first dose, we reported an mRNA vaccine-induced perimyocarditis in a young patient with a history of recurrent myocardial inflammation episodes and progressive loss of cardiac performance. We tested this possible inflammatory cytokine-mediated cardiotoxicity after vaccination in the acute phase (ten days), and we found a significant elevation of MCP-1, IL-18, and IL-8 inflammatory mediators. Still, these cytokines decreased considerably at the recovery phase (42 days later). We used the cardiomyoblasts cell line to test the effect of serum on cell viability, observing that serum from the acute phase reduced the cell viability to 75%. We did not detect this toxicity in cells when we tested serum from the patient in the recovery phase. We also tested serum-induced hypertrophy, a phenomenon in myocarditis and heart failure. We found that acute phase-serum has hypertrophy effects, increasing 25% of the treated cardiac cells' surface and significantly increasing B-type natriuretic peptide. However, we did not observe the hypertrophic effect in the recovery phase or sera from healthy controls. CONCLUSION: Our results opened the possibility of the inflammatory cytokines or serum soluble mediators as key factors for vaccine-associated myocarditis. In this regard, identifying anti-inflammatory molecules that reduce inflammatory cytokines could help avoid vaccine-induced myocardial inflammation.

A cross-sectional study evidences regulations of leukocytes in the colostrum of mothers with obesity.

BACKGROUND: Breastmilk is a dynamic fluid whose initial function is to provide the most adapted nutrition to the neonate. Additional attributes have been recently ascribed to breastmilk, with the evidence of a specific microbiota and the presence of various components of the immune system, such as cytokines and leukocytes. The composition of breastmilk varies through time, according to the health status of mother and child, and altogether contributes to the future health of the infant. Obesity is a rising condition worldwide that creates a state of systemic, chronic inflammation including leukocytosis. Here, we asked whether colostrum, the milk produced within the first 48 h post-partum, would contain a distinct leukocyte composition depending on the body mass index (BMI) of the mother. METHODS: We collected peripheral blood and colostrum paired samples from obese (BMI > 30) and lean (BMI < 25) mothers within 48 h post-partum and applied a panel of 6 antibodies plus a viability marker to characterize 10 major leukocyte subpopulations using flow cytometry. RESULTS: The size, internal complexity, and surface expression of CD45 and CD16 of multiple leukocyte subpopulations were selectively regulated between blood and colostrum irrespective of the study groups, suggesting a generalized cell-specific phenotype alteration. In obesity, the colostrum B lymphocyte compartment was significantly reduced, and CD16+ blood monocytes had an increased CD16 expression compared to the lean group. CONCLUSIONS: This is the first characterization of major leukocyte subsets in colostrum of mothers suffering from obesity and the first report of colostrum leukocyte subpopulations in Latin America. We evidence various significant alterations of most leukocyte populations between blood and colostrum and demonstrate a decreased colostrum B lymphocyte fraction in obesity. This pioneering study is a stepping stone to further investigate active immunity in human breastmilk.

Unexpected arterial thrombosis and acute limb ischemia in COVID-19 patients. Results from the Ibero-Latin American acute arterial thrombosis registry in COVID-19: (ARTICO-19).

OBJECTIVE: Few studies have focused on arterial thrombosis and acute limb ischemia in COVID-19. This international registry intended to study the spectrum of clinical characteristics, therapeutic trends, and outcomes in a cohort of Ibero-Latin American patients with arterial thrombosis or acute limb ischemia and COVID-19. METHODS: Data were retrospectively obtained from 21 centers in 9 countries. Patients with proven COVID-19 and asymptomatic or symptomatic arterial thrombosis were included. COVID-19 diagnosis was established by RT-PCR assay or IgM serology plus suggestive clinical/radiographical findings. We recorded and analyzed variables related to demography, clinical presentation, therapeutic trends, and outcomes. RESULTS: Eighty one patients were included in the registry. In 38.3%, acute limb ischemia symptoms were the first manifestation of COVID-19. Non-surgical management was more frequent in severe cases than surgical interventions, 11.1% vs. 88.9%, respectively (p = 0.004). Amputation rates were similar between all COVID severity groups (p = 0.807). Treatment was classified as non-surgical, open surgical, and endovascular treatment. Further analysis revealed an equal frequency of major leg amputation between treatment groups and increased mortality in patients with non-surgical management. However, multivariate regression analysis showed that treatment choices are associated with disease severity, with significant non-surgical treatment in critical patients; thus, mortality is related to the severity and confounds treatment analysis. CONCLUSION: Arterial thrombosis can be the initial symptom of a patient presenting with COVID-19. Physicians and health workers should potentially suspect COVID-19 in acute ischemia cases without a known risk factor or embolic cause. More experimental and clinical research is required to understand the complex phenomenon of arterial COVID-19 induced coagulopathy fully.

Covid-19 mortality in children and adolescents in Mexico.

OBJECTIVE: To estimate Covid-19 and pre-pandemic low respiratory infection (LRI) mortality in children and adolescents in Mexico. MATERIALS AND METHODS: We estimated the percentage of total mortality attributable to Covid-19 (95% confidence intervals; 95%CI) and made the corresponding estimates for pre-pandemic LRI mortality. RESULTS: In 2019, LRIs represented 8.6% (95%CI 8.3, 8.9) of deaths in children aged 0-9 years, and 2.0% (95%CI 1.8, 2.3) in those aged 10-19 years. In 2020, the corresponding estimates for Covid-19 were 4.4% (95%CI 4.1, 4.6) and 3.7% (95%CI 3.4, 4.1). CONCLUSIONS: Relative to LRI, Covid-19 may be exerting a considerable mortality burden, particularly in older children and adolescents.

Differences between surviving and non-surviving venous thromboembolism COVID-19 patients: a systematic review.

BACKGROUND: To our knowledge, the treatment, outcome, clinical presentation, risk stratification of patients with venous thromboembolism and COVID-19 have not been well characterized. METHODS: We searched for systematic reviews, cohorts, case series, case reports, editor letters, and venous thromboembolism COVID-19 patients' abstracts following PRISMA and PROSPERO statements. We analyzed therapeutic approaches and clinical outcomes of venous thromboembolism COVID-19 patients. Inclusion: COVID-19 patients with venous thromboembolism confirmed by an imaging method (venous doppler ultrasound, ventilation-perfusion lung scan, computed tomography pulmonary angiogram, pulmonary angiography). We assessed and reported the original Pulmonary Embolism Severity Index for each pulmonary embolism patient. In addition, we defined major bleedings according to the International Society of Thrombosis and Haemostasis criteria. RESULTS: We performed a systematic review from August 9 to August 30, 2020. We collected 1,535 papers from PubMed, Scopus, Web of Science, Wiley, and Opengrey. We extracted data from 89 studies that describe 143 patients. Unfractionated and low-molecular-weight heparin was used as parenteral anticoagulation in 85/143 (59%) cases. The Food and Drug Administration-approved alteplase regimen guided the advanced treatment in 39/143 (27%) patients. The mortality was high (21.6%, CI 95% 15.2-29.3). The incidence of major bleeding complications was 1 (0.9%) in the survival group and 1 (3.2%) in the death group. Pulmonary Embolism Severity Index was class I in 11.6% and II in 22.3% in survivors compared to 0% and 6.5% in non-survivors, respectively. Patients who experienced venous thromboembolism events at home were more likely to live than in-hospital events. CONCLUSIONS: We determined a high mortality incidence of pulmonary embolism and a low rate of bleeding. Unfractionated and low-molecular-weight heparin drove parenteral anticoagulation and alteplase the advanced treatment in both groups. The original Pulmonary Embolism Severity Index could be helpful in the risk stratification.

Seroprevalencia de SARS-CoV-2 en niños y adolescentes mexicanos en edad escolar.

Objetivo. Estimar la seroprevalencia de SARS-CoV-2 en población de edad escolar en México. Material y métodos. Se categorizaron a niños y adolescentes que participaron en la Encuesta Nacional de Salud y Nutrición 2020 sobre Covid-19 (Ensanut 2020 Covid-19) por edad escolar y nivel educativo. En participantes seropositivos, se identificó la proporción de infecciones asintomáticas. Se estimaron razones de prevalencia usando un modelo de regresión log-binomial. Resultados. La seroprevalencia en educación básica y media fue de 18.7% (IC95%: 14.9, 22.5) y 26.7% (IC95%: 22.1, 31.3), respectivamente. La infección asintomática fue más frecuente en educación básica (88.5% [IC95%: 80.5, 93.5]). Conclusiones. En población de educación básica la infección por SARS-CoV-2 es baja y usualmente asintomática.

Clinical and Epidemiological Characteristics of Paediatric Patients Diagnosed with COVID-19 in a Tertiary Hospital in Mexico City.

COVID-19 affects the paediatric population less frequently than adults. A retrospective study was performed in a tertiary paediatric hospital in Mexico City in children <18 years of age who were hospitalized with a positive reverse transcription-polymerase chain reaction for SARS-CoV-2. Included in the study were 86 patients with a median age of 10 years old (IQR 2.6-14.3 years), who were classified in three groups: previously healthy, with chronic disease and immunosuppressed patients. The principal signs and symptoms were fever (81%), cough (51%) and headache (35%). A total of 20 patients (23%) required management in the paediatric intensive care unit (PICU) and 17% needed mechanical ventilation for an average of 12.7 days (IQR 2-29 days). There was no statistically significant difference between the three clinical classification groups in those patients admitted to the PICU, most of which were previously healthy patients. The mortality rate was 5% (four patients). Given that the paediatric population is susceptible to infection, potential transmitters and to clinical presentations with variable degrees of severity, it is important to continue reinforcing social distancing measures.

Interventional pain training using phantom model during COVID-19 pandemic.

BACKGROUND: Fluoroscopic-guided lumbar procedures have increased in daily pain practice because the lumbar spine is one of the most common sources of pain. Interventional pain fellows must develop a minimum number of skills during their training in order to achieve the competences without neglecting radiological safety. However, medical training in fluoroscopic-guided interventions is being affected by the current coronavirus disease 2019 (COVID-19) situation. METHODS: The objective of this study was to evaluate the use of a phantom model for lumbar injection as a training strategy during the COVID-19 pandemic in fellows of interventional pain. The study was divided into theoretical and practical modules. The hands-on practice was performed in a lumbar model phantom where fellows were evaluated in four fluoroscopically guided approaches: intra-articular facet block (IAFB), medial branch block (MBB), transforaminal block (TFB), and interlaminar block (ILB) divided in 5 sessions. The aim was to make as many punctures as possible in every session. We measured total procedural performance (TPP), total needle hand time (TNH), and total radiation dose generated by the fluoroscopic machine (TRD) during each procedure. Additionally, a survey was applied to evaluate confidence and satisfaction before and after training. RESULTS: A total of 320 lumbar punctures were completed. The results were statistically significant in all approaches attempted (p < 0.01). The fellow's survey for satisfaction and confidence demonstrated a significant difference between pre and post-test (p < 0.01). CONCLUSIONS: The results of this study highlight the importance of adaptations and adoption of new educational models. The use of the phantom model for simulation could be a strategy for other emerging situations, like the COVID-19 pandemic. Including this practice in the interventional pain programs could lead to better results for the patient and operator radiology safety.

Co-infection with Streptococcus anginosus and Mycobacterium tuberculosis in an immunocompetent pediatric patient. A case report.

BACKGROUND: Simultaneous infection in tuberculosis (TB) is rare. The mixed infection between Streptococcus anginosus group (SAG) and M. tuberculosis (MTB) has not been reported in children. The aim of this report was to describe a pediatric case with a pulmonary abscess caused by the duality SAG-MTB co-infection. CASE PRESENTATION: An 11-year-old boy with an acute onset of throbbing pain of two-day evolution located in the anterior chest wall. The patient reported a history of fever, cough and rhinorrhea during the last seven days. An anterior chest radiography revealed a heterogenic opacity at the lower right lobe while the lateral projection showed an obliteration at the anterior diaphragmatic insertion. Parenteral Ceftriaxone (100 mg/kg/day) and Dicloxacillin (200 mg/kg/day) was started. The abscess was subsequently drained and analyzed. After a year of follow-up, the patient remained asymptomatic. CONCLUSION: This case represents the first reported case of pulmonary co-infection involving MTB and SAG in an immunocompetent pediatric patient.

What Is the Role of the Inflammation in the Pathogenesis of Heart Failure?

PURPOSE OF REVIEW: In heart failure, whether it is associated with reduced or preserved ejection fraction, the immune system is activated and contributes to heart remodeling and impaired function. RECENT FINDINGS: Studies indicate that cells of the immune system not only play a role in the pathology but are also critical regulators of heart function. Knowledge about the role of the immune system driving heart failure will lead to the development of new targets to this system, particularly in those patients that, despite the apparent wellness, relapse and worsen. In this review, we will address the diverse mechanisms that trigger inflammation and their impact on heart failure progression.

Carbapenemase-producing Enterobacteriaceae in Mexico: report of seven non-clonal cases in a pediatric hospital.

BACKGROUND: Carbapenemases-producing Enterobacteriaceae (CPE) are a worldwide public health emergency. In Mexico, reports of CPE are limited, particularly in the pediatric population. Here, we describe the clinical, epidemiological, and molecular characteristics of seven consecutive cases in a third-level pediatric hospital in Mexico City over a four-month period during 2016. RESULTS: The Enterobacteriaceae identified were three Escherichia coli strains (producing OXA-232, NDM-1 and KPC-2), two Klebsiella pneumoniae strains (producing KPC-2 and NDM-1), one Klebsiella oxytoca strain producing OXA-48 and one Enterobacter cloacae strain producing NDM-1. The majority of patients had underlying disesases, three were immunocompromised, and three had infections involved the skin and soft tissues. Half patients died as a result of CPE infection. CONCLUSIONS: This study represents the first report of E. coli ST131-O25b clone producing NDM-1 in Latin America. In addition, this study is the first finding of K. oxytoca producing OXA-48 and E. coli producing OXA-232 in Mexican pediatric patients.

Black Lives Matter, but What About Our Health?

In the setting of the current social and political climate, the focus on protection of Black lives in America has come to the forefront. We evaluate how health in the Black community should be a paramount concern that can be addressed in three ways: 1. Connecting the medical community to the Black community, empowering patients with knowledge, and diversifying the medical workforce. These three initiatives will help to decrease the health disparities seen in Black health.

Temporal Frame of Immune Cell Infiltration during Heart Failure Establishment: Lessons from Animal Models.

Heart failure (HF) is a cardiovascular syndrome characterized by maladaptive changes with an underlying inflammatory mediated pathogenesis. Nevertheless, current therapy is aimed at the heart workload and neurohormonal axis; thus, prognosis remains poor. To continue improving treatment, we rely on murine models for a better understanding of HF pathophysiology. Among them, pressure overload HF (PO-HF) animal models are a common strategy. Development of PO-HF is characterized by monocyte infiltration, which orchestrates a cascade of events leading to sustained inflammation and maladaptive changes. Here, we divide the PO-HF model progression into four phases and describe the inflammatory, structural, and gene expression profiles. This division is relevant due to its similarities with clinical hypertensive heart disease progression to HF. Evidence shows improvement in hemodynamic and other local parameters by altering the inflammatory response in a specific immune response at a specific point of time. Thus, it is relevant to focus on the time-dependent immune response interaction in order to provide more effective therapy. This review summarizes the pathogenesis of PO-HF murine models, highlighting the inflammatory events in a time frame view. By this approach, we expect to provide researchers with a better understanding of the intertwining time-dependent events that occur in PO-HF.

Venous thromboembolism: thrombosis, inflammation, and immunothrombosis for clinicians.

Venous thromboembolism (VTE) is a worldwide disease related with mortality, cardiovascular disability, impaired quality of life and, cause major long-term complications. Clinicians related to the acute and long-term patients care must be involved in the molecular mechanisms of thrombosis. The vessel wall and its inner lining of the endothelium are critical to the maintenance of a patent vasculature. After endothelial disruption, collagen (first line of endothelial defense) and intravascular tissue factor (second line of endothelial defense) are exposed to blood flow, starting the formation of a thrombus. Anticoagulant endovascular proteins and endogenous fibrinolysis have an active role in hemostasis. Currently, the process of coagulation is a cell surface-based model that includes three overlapping phases: initiation, amplification, and propagation. From a simple view, inflammation is one of the first responses of the immune system to infection; inflammation is driven by eicosanoids and cytokines, which are released by injured or infected cells. Common cytokines, which regulate inflammatory response, include interleukins (mainly interleukin-6) that are responsible for communication among white blood cells, chemokines that promote chemotaxis, and interferons that have anti-viral effects. Acute infections have been associated with a transient increase in the risk of myocardial infarction, stroke and recently with venous thrombosis, supporting the notion that systemic and respiratory infections increase the risk of thromboembolic events. Recently, immunothrombosis, another thrombosis mechanism that includes innate immune mechanisms, the neutrophil extracellular genetic traps, and the immunothrombosis dysregulation, could explain some cases of "unprovoked" VTE especially in elderly, a high-risk population for thrombosis.

Assessment of immune reconstitution status in recipients of a successful hematopoietic stem cell transplant from peripheral blood after reduced intensity conditioning.

OBJECTIVE: To document immune reconstitution status after hematopoietic stem cell transplantation (HSCT) for malignant hematologic diseases. METHODS: Hematology patients who received a reduced intensity conditioning (RIC) were followed after successful allogeneic or autologous HSCT. Patients had at least 100days post-transplant. T, B and NK cells in peripheral blood (PB), and CD34+, CD133+ progenitor cells in bone marrow (BM) and peripheral blood (PB) were determined by flow cytometry. RESULTS: Twenty-seven HSCT recipients, 19 allogeneic and 8 autologous, were studied at a median 155 (100-721) days post-transplant. In the whole group the median value of CD34+ cells was 1.03% in the bone marrow and 0.04% in PB, whereas values for CD133+ cells were 0.39% and 0.13%, respectively, without statistical differences between autologous and allogeneic recipients. Significantly more B cells (CD3-/CD56-/CD19+) were found in the autologous compared to the allogeneic group, 12.6 vs. 5.01, p=0.04. An increased number of CD8+ lymphocytes with a 0.63 CD4:CD8 relationship was documented in PB. CONCLUSION: In clinically recovered autologous and allogeneic HSCT recipients BM and PB CD34+/CD133+ hematoprogenitor homeostasis is maintained within normal ranges, with better B-cell reconstitution in the autologous group.

Increased bacterial infections after transfusion of leukoreduced non-irradiated blood products in recipients of allogeneic stem cell transplants after reduced-intensity conditioning.

Blood components transfused to hematopoietic stem cell transplant (HSCT) recipients are irradiated to prevent transfusion-associated graft-versus-host disease (TA-GVHD). The effect of transfusing non-irradiated blood products in HSCT outcome, including incidence of transplant complications, bacterial infections, acute and chronic GVHD presentation, and characteristics, has not been documented. Clinical records as well as blood bank and electronic databases of HSCT patients grafted after reduced-intensity conditioning who received irradiated versus non-irradiated blood products, after blood irradiation became unavailable at our center, were scrutinized for transplant outcome, clinical evolution, engraftment characteristics including days to neutrophil and platelet recovery, acute and chronic GVHD, rate and type of infections, and additional transplant-related comorbidities. All transfused blood products were leukoreduced. A total of 156 HSCT recipients was studied, 73 received irradiated and 83 non-irradiated blood components. Bacterial infections were significantly more frequent in patients transfused with non-irradiated blood products, P = .04. Clinically relevant increased rates of fever and neutropenia and mucositis were also documented in these patients. No cases of TA-GVHD occurred. Classical GVHD developed in 37 patients (50.7%) who received irradiated blood products and 36 (43.9%) who received non-irradiated blood products, P = .42. Acute GVHD developed in 28 patients (38.4%) in the blood-irradiated and 33 patients (39.8%) in the non-irradiation group, P = .87. The 2-year GVHD-free survival rate was 40% in the irradiated versus 40.6% in the non-irradiation group, P = .071. Increased bacterial infections were found in HSCT recipients transfused with non-irradiated blood products, which ideally must always be irradiated.

[Nutritional approaches to modulate oxidative stress that induce Alzheimer's disease. Nutritional approaches to prevent Alzheimer's disease]. / Nutrición que previene el estrés oxidativo causante del Alzheimer. Prevención del Alzheimer.

Alzheimer's disease is the most common cause of dementia in the world; symptoms first appear after age 65 and have a progressive evolution. Expecting an increase on its incidence and knowing there is currently no cure for Alzheimer's disease, it is a necessity to prevent progression. The change in diet due to globalization may explain the growth of the incidence in places such as Japan and Mediterranean countries, which used to have fewer incidences. There is a direct correlation between disease progression and the increased intake of alcohol, saturated fats, and red meat. Therefore, we find obesity and higher serum levels in cholesterol due to saturated fat as a result. A way to decrease the progression of Alzheimer's is through a diet rich in polipheno/es (potent antioxidants), unsaturated fats (monounsaturated and polyunsaturated), fish, vegetable fa t, fruits with low glycemic index, and a moderate consumption of red wine. Through this potent antioxidant diet we accomplish the prevention of dementia and the progression of Alzheimer's disease. This article emphasizes the food and other components that have been demonstrated to decrease the oxidative stress related to these progressive diseases.

Global Antimicrobial Susceptibility Patterns of Staphylococcus aureus in Atopic Dermatitis: A Systematic Review and Meta-Analysis.

Importance: Individuals with atopic dermatitis are frequently colonized and infected with Staphylococcus aureus. Empirical antibiotic therapy for individuals with atopic dermatitis is common, but data about the antimicrobial susceptibility profiles of S aureus strains isolated from these individuals are scarce for those living in particular geographic areas. Objective: To determine the antimicrobial susceptibility of S aureus from individuals with atopic dermatitis and analyze differences according to the income level of the country of origin and the data collection period. Data Sources: A meta-analysis of the literature was performed from the inception of the included databases (MEDLINE, Embase, Web of Science, Scopus, and Cochrane) to June 20, 2023, using predetermined Medical Subject Headings. Study Selection: Studies were included if they reported antibiotic susceptibility profiles of 1 or more S aureus cutaneous isolates from individuals with atopic dermatitis. Articles written in English, Spanish, French, or German were included. Data Extraction and Synthesis: Working in pairs, 6 of the authors conducted the data extraction. The guidelines from the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) were followed. Main Outcomes and Measures: The outcome of interest was antimicrobial susceptibility. Results: A total of 61 studies reported 4091 S aureus isolates from individuals with atopic dermatitis. For 4 of the 11 commonly used antibiotics (36.4%), antimicrobial susceptibility was 85% or less, including for methicillin (binomial proportion, 0.85 [95% CI, 0.76-0.91]), erythromycin (binomial proportion, 0.73 [95% CI, 0.61-0.83]), fusidic acid (binomial proportion, 0.80 [95% CI, 0.62-0.91]), and clindamycin (binomial proportion, 0.79 [95% CI, 0.65-0.89]). Most studies (46; 75.4%) were conducted in high-income countries. Antimicrobial susceptibility to erythromycin, methicillin, and trimethoprim and sulfamethoxazole was significantly lower in lower middle-income countries and upper middle-income countries. Regarding the temporal trends, 33 studies (54.1%) reported data collected from 1998 to 2010. Antimicrobial susceptibility patterns have not changed over time. Conclusions and Relevance: In this systematic review and meta-analysis, antimicrobial susceptibility of S aureus to ß-lactams, erythromycin, clindamycin, and fusidic acid may be suboptimal for empirical use in individuals with atopic dermatitis. Significant differences in antimicrobial susceptibility patterns were found in high-income countries and in lower middle-income countries and upper middle-income countries for some antibiotics.

Advancing Cardiac Care: A Registry of Heart Transplantation in Latin America (1968-2022).

INTRODUCTION: Heart transplantation (HTx) has emerged as a pivotal intervention for end-stage heart failure, offering significant improvements in survival and quality of life. This manuscript elucidates the landscape of HTx across Latin America (LATAM) from its advent in 1968 through December 2022, shedding light on its evolution, current practices, and regional disparities. METHODS: We distributed a structured questionnaire to the national coordinators or representatives of the Interamerican Council of Heart Failure and Pulmonary Hypertension, collating responses from 20 LATAM nations. This approach facilitated a comprehensive aggregation of regional HTx data. RESULTS: A total of 12,374 HTx were performed in 166 centers across 16 LATAM countries, with Brazil, Argentina, and Colombia accounting for the majority of procedures. Pediatric transplants represented 9% of the total caseload, and combined organ transplants were reported in 62.5% of the participating countries, underscoring the complexity and breadth of transplant services in the region. CONCLUSION: Despite facing infrastructural and logistical challenges, LATAM has demonstrated a robust capacity to conduct high-complexity transplant procedures. The establishment of a structured, regional HTx registry is imperative to enhance data collection and analysis, which in turn can inform clinical decision-making and policy development, ultimately improving patient outcomes across the continent.

Mitochondrial Ca2+ Uniporter-Dependent Energetic Dysfunction Drives Hypertrophy in Heart Failure.

The role of the mitochondrial calcium uniporter (MCU) in energy dysfunction and hypertrophy in heart failure (HF) remains unknown. In angiotensin II (ANGII)-induced hypertrophic cardiac cells we have shown that hypertrophic cells overexpress MCU and present bioenergetic dysfunction. However, by silencing MCU, cell hypertrophy and mitochondrial dysfunction are prevented by blocking mitochondrial calcium overload, increase mitochondrial reactive oxygen species, and activation of nuclear factor kappa B-dependent hypertrophic and proinflammatory signaling. Moreover, we identified a calcium/calmodulin-independent protein kinase II/cyclic adenosine monophosphate response element-binding protein signaling modulating MCU upregulation by ANGII. Additionally, we found upregulation of MCU in ANGII-induced left ventricular HF in mice, and in the LV of HF patients, which was correlated with pathological remodeling. Following left ventricular assist device implantation, MCU expression decreased, suggesting tissue plasticity to modulate MCU expression.