Lack of diversity regarding genetic and environmental backgrounds weakens the generalization and clinical applicability of research findings on psychotic disorders. Notably, Latin Americans have been generally neglected in genetic studies, comprising less than 2% of genome-wide association study samples. But Latin American populations represent a unique opportunity for research, given the exceptionally high ethnic admixture of this group. Increasing genetic diversity is essential to improve the fine mapping of known regions associated with psychotic disorders, discover novel genetic associations, and replicate studies. Additionally, Latin America is characterized by massive social, political, and economic inequalities, all known risk factors for mental health issues, including psychotic disorders. This article aims to 1) discuss the challenges and advantages of studying Latin America’s particular genetic makeup and environmental context; 2) review previous studies conducted in the region; and 3) describe three Latin American research initiatives in progress: the Neuropsychiatric Genetics of Psychosis in Mexican Populations (NeuroMEX), the Paisa, and the Latin American Network for the Study of Early Psychosis (ANDES) studies.

RESUMO Objetivo: avaliar a dismotilidade esofágica (DE) e a extensão do esôfago de Barrett (EB) antes e depois da fundoplicatura laparoscópica a Nissen (FLN) em pacientes previamente diagnosticados com EB e DE. Método: vinte e dois pacientes com EB diagnosticada por endoscopia digestiva alta (EDA) com biópsias e DE diagnosticada por manometria esofágica convencional (MEC) foram submetidos a FLN, e acompanhados por avaliações clínicas, endoscopia digestiva alta com biópsias e MEC, por no mínimo 12 meses após o procedimento cirúrgico. Resultados: dezesseis pacientes eram do sexo masculino (72,7%) e seis do feminino (27,3%). A média de idade foi de 55,14 (± 15,52) anos e o seguimento pós-operatório médio foi de 26,2 meses. A endoscopia digestiva alta mostrou que o comprimento médio do EB foi de 4,09 cm no pré-operatório e 3,91 cm no pós-operatório (p = 0,042). A avaliação da dismotilidade esofágica por meio da manometria convencional mostrou que a mediana pré-operatória da pressão de repouso do esfíncter esofágico inferior (PREEI) foi de 9,15 mmHg, e de 13,2 mmHg no pós-operatório (p = 0,006). A mediana pré-operatória da amplitude de contração esofágica foi de 47,85 mmHg, e de 57,50 mmHg no pós-operatório (p = 0,408). A avaliação pré-operatória do peristaltismo esofágico mostrou que 13,6% da amostra apresentava espasmo esofágico difuso e 9,1%, motilidade esofágica ineficaz. No pós-operatório, 4,5% dos pacientes apresentaram espasmo esofágico difuso, 13,6% de aperistalse e 22,7% de atividade motora ineficaz (p = 0,133). Conclusões: a FLN diminuiu a extensão do EB, aumentou a pressão de repouso do EEI e aumentou a amplitude da contração esofágica distal; no entanto, não foi capaz de melhorar a DE.

ABSTRACT Objective: to evaluate esophageal dysmotility (ED) and the extent of Barrett’s esophagus (BE) before and after laparoscopic Nissen fundoplication (LNF) in patients previously diagnosed with BE and ED. Methods: twenty-two patients with BE diagnosed by upper gastrointestinal (GI) endoscopy with biopsies and ED diagnosed by conventional esophageal manometry (CEM) were submitted to a LNF, and followed up with clinical evaluations, upper GI endoscopy with biopsies and CEM, for a minimum of 12 months after the surgical procedure. Results : sixteen patients were male (72.7%) and six were females (27.3%). The mean age was 55.14 (± 15.52) years old. and the mean postoperative follow-up was 26.2 months. The upper GI endoscopy showed that the mean length of BE was 4.09 cm preoperatively and 3.91cm postoperatively (p=0.042). The evaluation of esophageal dysmotility through conventional manometry showed that: the preoperative median of the lower esophageal sphincter resting pressure (LESRP) was 9.15 mmHg and 13.2 mmHg postoperatively (p=0.006). The preoperative median of the esophageal contraction amplitude was 47.85 mmHg, and 57.50 mmHg postoperatively (p=0.408). Preoperative evaluation of esophageal peristalsis showed that 13.6% of the sample presented diffuse esophageal spasm and 9.1% ineffective esophageal motility. In the postoperative, 4.5% of patients had diffuse esophageal spasm, 13.6% of aperistalsis and 22.7% of ineffective motor activity (p=0.133). Conclusion: LNF decreased the BE extension, increased the LES resting pressure, and increased the amplitude of the distal esophageal contraction; however, it was unable to improve ED.