CFTR pathogenic variants spectrum in a cohort of Mexican patients with cystic fibrosis.

Background: Molecular diagnosis of cystic fibrosis (CF) is challenging in Mexico due to the population's high genetic heterogeneity. To date, 46 pathogenic variants (PVs) have been reported, yielding a detection rate of 77%. We updated the spectrum and frequency of PVs responsible for this disease in mexican patients. Methods: We extracted genomic DNA from peripheral blood lymphocytes obtained from 297 CF patients and their parents. First, we analyzed the five most frequent PVs in the Mexican population using PCR-mediated site-directed mutagenesis. In patients with at least one identified allele, CFTR sequencing was performed using next-generation sequencing tools and multiplex ligation-dependent probe amplification. For variants not previously classified as pathogenic, we used a combination of in silico prediction, CFTR modeling, and clinical characteristics to determine a genotype-phenotype correlation. Results: We identified 95 PVs, increasing the detection rate to 87.04%. The most frequent variants were p.(PheF508del) (42.7%), followed by p.(Gly542*) (5.6%), p.(Ser945Leu) (2.9%), p.(Trp1204*) and p.(Ser549Asn) (2.5%), and CFTRdel25-26 and p.(Asn386Ilefs*3) (2.3%). The remaining variants had frequencies of <2.0%, and some were exclusive to one family. We identified 10 novel PVs localized in different exons (frequency range: 0.1-0.8%), all of which produced structural changes, deletions, or duplications in different domains of the protein, resulting in dysfunctional ion flow. The use of different in silico software and American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) criteria allowed us to assume that all of these PVs were pathogenic, causing a severe phenotype. Conclusions: In a highly heterogeneous population, combinations of different tools are needed to identify the variants responsible for CF and enable the establishment of appropriate strategies for CF diagnosis, prevention, and treatment.

Association of biological sex with clinical outcomes and biomarkers of Alzheimer's disease in adults with Down syndrome.

The study of sex differences in Alzheimer's disease is increasingly recognized as a key priority in research and clinical development. People with Down syndrome represent the largest population with a genetic link to Alzheimer's disease (>90% in the 7th decade). Yet, sex differences in Alzheimer's disease manifestations have not been fully investigated in these individuals, who are key candidates for preventive clinical trials. In this double-centre, cross-sectional study of 628 adults with Down syndrome [46% female, 44.4 (34.6; 50.7) years], we compared Alzheimer's disease prevalence, as well as cognitive outcomes and AT(N) biomarkers across age and sex. Participants were recruited from a population-based health plan in Barcelona, Spain, and from a convenience sample recruited via services for people with intellectual disabilities in England and Scotland. They underwent assessment with the Cambridge Cognitive Examination for Older Adults with Down Syndrome, modified cued recall test and determinations of brain amyloidosis (CSF amyloid-ß 42 / 40 and amyloid-PET), tau pathology (CSF and plasma phosphorylated-tau181) and neurodegeneration biomarkers (CSF and plasma neurofilament light, total-tau, fluorodeoxyglucose-PET and MRI). We used within-group locally estimated scatterplot smoothing models to compare the trajectory of biomarker changes with age in females versus males, as well as by apolipoprotein ɛ4 carriership. Our work revealed similar prevalence, age at diagnosis and Cambridge Cognitive Examination for Older Adults with Down Syndrome scores by sex, but males showed lower modified cued recall test scores from age 45 compared with females. AT(N) biomarkers were comparable in males and females. When considering apolipoprotein ɛ4, female ɛ4 carriers showed a 3-year earlier age at diagnosis compared with female non-carriers (50.5 versus 53.2 years, P = 0.01). This difference was not seen in males (52.2 versus 52.5 years, P = 0.76). Our exploratory analyses considering sex, apolipoprotein ɛ4 and biomarkers showed that female ɛ4 carriers tended to exhibit lower CSF amyloid-ß 42/amyloid-ß 40 ratios and lower hippocampal volume compared with females without this allele, in line with the clinical difference. This work showed that biological sex did not influence clinical and biomarker profiles of Alzheimer's disease in adults with Down syndrome. Consideration of apolipoprotein ɛ4 haplotype, particularly in females, may be important for clinical research and clinical trials that consider this population. Accounting for, reporting and publishing sex-stratified data, even when no sex differences are found, is central to helping advance precision medicine.

Impact of CSF storage volume on the analysis of Alzheimer's disease biomarkers on an automated platform.

OBJECTIVES: To assess the potential influence of the ratio between the storage tube surface area and the volume of cerebrospinal fluid (CSF) (surface/volume) on the quantifications of four Alzheimer's disease (AD) biomarkers on the Lumipulse G600II automated platform. METHODS: CSF samples of 10 consecutive patients were stored in 2 ml polypropylene tubes containing four different CSF volumes: 1.5 ml, 1 ml, 0.5 ml and 0.25 ml. Concentration of CSF Aß1-42, Aß1-40, t-Tau and p-Tau were measured in all aliquots using the LUMIPULSE G600II automated platform from Fujirebio. RESULTS: Levels of CSF Aß1-42 and Aß1-40 were lower in samples stored with lower volumes (higher surface/volume ratios). This decrease was partly compensated by using the ratio Aß1-42/Aß1-40. Quantification of t-Tau and p-Tau were not influenced by this pre-analytical condition. CONCLUSION: The surface/volume ratio can potentially influence the results of amyloid AD biomarkers. It appears essential to take into account the surface/volume ratio of the storage tubes when quantifying CSF biomarkers in clinical routine.

A rede de urgência e emergência da macrorregião norte de Minas Gerais: um estudo de caso / The emergency network in the northern macro-region of Minas Gerais, Brazil: a case study

A atenção a Urgência e Emergência é um desafio a ser enfrentado pelo Sistema Único de Saúde e demanda dos gestores a organização deste. Para atender a essa demanda, a Secretaria de Estado de Saúde de Minas Gerais propôs a construção da Rede de Atenção de Urgência e Emergência na Macrorregião Norte de Minas Gerais, sendo a compreensão de seu funcionamento o objetivo deste artigo. Trata-se de uma pesquisa qualitativa e exploratória do tipo estudo de caso. A coleta de dados foi feita mediante pesquisa documental, observação e entrevistas com informantes-chave, membros do Comitê Gestor e profissionais da Secretaria de Estado que acompanham a Rede de Atenção à Urgência e Emergência do Norte de Minas. Os resultados indicam dificuldades, facilidades e avanços no processo. Entre as facilidades, tem-se a implantação da rede, a criação do Comitê, a regionalização do Serviço de Atenção Móvel de Urgência, a adoção da classificação de risco e o suporte do Estado. Entre as dificuldades, estão o modelo de financiamento, a extensão territorial, o despreparo e a rotatividade dos profissionais. Já o avanço foi o maior acesso. Conclui-se ser este um processo complexo e dinâmico, que envolve diversos e diferentes atores. Trata-se de ação pioneira e ousada, que, a despeito das dificuldades, tem se mostrado bastante positiva.

The attention to the Urgency and Emergency sectors is a challenge to be faced by the Unified Health System and demands organization from the health managers. In order to respond to this demand, the State Secretary of Health has proposed the implementation of the Urgency and Emergency Attention Network in the Northern Macro-region of Minas Gerais, and this article, a qualitative and exploratory research in the form of a case study, aims to understand its function. The data was collected through documental research, observation and interviews with key-informants (members of the Managerial Committee and professionals of the Secretariat of State who accompany the Urgency and Emergency Attention Network in the North of Minas Gerais). The results point at difficulties, but also at positive aspects and advances. On the positive end are the network implementation, the Committee creation, the Emergency Mobile Health Care regionalization, the risk classification and the State support. On the negative end are the financing model, the large territory, the workers' lack of prepare, and their high turnover. As advances, the better access to the services is highlighted. The conclusion is that this is a complex and dynamic process that involves many different actors. This network is an innovative and audacious action, which, despite the difficulties, has proved to be very positive.