The full spectrum of SLC22 OCT1 mutations illuminates the bridge between drug transporter biophysics and pharmacogenomics.

Mutations in transporters can impact an individual's response to drugs and cause many diseases. Few variants in transporters have been evaluated for their functional impact. Here, we combine saturation mutagenesis and multi-phenotypic screening to dissect the impact of 11,213 missense single-amino-acid deletions, and synonymous variants across the 554 residues of OCT1, a key liver xenobiotic transporter. By quantifying in parallel expression and substrate uptake, we find that most variants exert their primary effect on protein abundance, a phenotype not commonly measured alongside function. Using our mutagenesis results combined with structure prediction and molecular dynamic simulations, we develop accurate structure-function models of the entire transport cycle, providing biophysical characterization of all known and possible human OCT1 polymorphisms. This work provides a complete functional map of OCT1 variants along with a framework for integrating functional genomics, biophysical modeling, and human genetics to predict variant effects on disease and drug efficacy.

Haploinsufficiency underlies the neurodevelopmental consequences of SLC6A1 variants.

Heterozygous variants in SLC6A1, encoding the GAT-1 GABA transporter, are associated with seizures, developmental delay, and autism. The majority of affected individuals carry missense variants, many of which are recurrent germline de novo mutations, raising the possibility of gain-of-function or dominant-negative effects. To understand the functional consequences, we performed an in vitro GABA uptake assay for 213 unique variants, including 24 control variants. De novo variants consistently resulted in a decrease in GABA uptake, in keeping with haploinsufficiency underlying all neurodevelopmental phenotypes. Where present, ClinVar pathogenicity reports correlated well with GABA uptake data; the functional data can inform future reports for the remaining 72% of unscored variants. Surface localization was assessed for 86 variants; two-thirds of loss-of-function missense variants prevented GAT-1 from being present on the membrane while GAT-1 was on the surface but with reduced activity for the remaining third. Surprisingly, recurrent de novo missense variants showed moderate loss-of-function effects that reduced GABA uptake with no evidence for dominant-negative or gain-of-function effects. Using linear regression across multiple missense severity scores to extrapolate the functional data to all potential SLC6A1 missense variants, we observe an abundance of GAT-1 residues that are sensitive to substitution. The extent of this missense vulnerability accounts for the clinically observed missense enrichment; overlap with hypermutable CpG sites accounts for the recurrent missense variants. Strategies to increase the expression of the wild-type SLC6A1 allele are likely to be beneficial across neurodevelopmental disorders, though the developmental stage and extent of required rescue remain unknown.

Amyloid-Negative, Neurodegeneration-Negative Amnestic Mild Cognitive Impairment.

Background: The concept of amnestic mild cognitive impairment (aMCI) was developed to identify patients at an initial stage of Alzheimer's disease (AD). However, some patients with aMCI do not present biomarkers of amyloid pathology or neuronal injury. Objective: To know the natural history of amyloid-negative and neurodegeneration-negative patients with aMCI, namely to ascertain: 1) whether these patients remain cognitively stable or they present a slow decline in neuropsychological tests; 2) whether the memory complaints subside with the apparently benign clinical course of the disorder or if they persist along the time. Methods: Patients who fulfilled criteria for aMCI with no biomarkers of amyloid pathology or neuronal injury were selected from a large cohort of non-demented patients with cognitive complaints, and were followed with clinical and neuropsychological assessments. Results: Twenty-one amyloid-negative and neurodegeneration-negative aMCI patients were followed for 7.1±3.7 years. At the baseline they had more pronounced deficits in verbal learning (California Verbal Learning Test) and were also impaired in Word Recall and Logical Memory. However, they did not decline in any cognitive test during follow-up. The patients maintained a high level of subjective memory complaints from baseline (9.7±4.1) to the follow-up visit (9.2±4.1, a non-significant difference), in spite of a statistically significant decrease in the depressive symptoms, with Geriatric Depression Scale (15 items) score 4.9±2.8 at baseline and 3.2±1.8 at the follow-up visit. Conclusions: Amyloid-negative, neurodegeneration-negative aMCI is a chronic clinical condition characterized by the long-term persistence of cognitive deficits and distressing memory complaints. Adequate strategies to treat this condition are needed.

Urogenital tuberculosis in a patient with end-stage renal disease

Abstract Tuberculosis is one of the most common infections worldwide with particularly high incidence rates in countries with unfavorable socioeconomic conditions and among persons with impaired immune systems. While most patients with this disease will present with pulmonary tuberculosis, immunocompromised individuals also commonly present with extrapulmonary manifestations. We report the case of a 28-year-old male patient with end-stage renal disease who presented with long-standing systemic symptoms and genitourinary manifestations, who was diagnosed with urogenital tuberculosis both by clinical and microbiologic criteria. Clinicians should always suspect tuberculosis in patients with chronic symptoms, especially in those with immunosuppression.

Contribuição do funcionamento executivo para o risco de obesidade extrema / Contribution of executive functioning to the risk of morbid obesity

O presente estudo tem como objetivo verificar se o funcionamento executivo pode influenciar o processo de obesidade extrema. Foi utilizada uma amostra composta por 48 participantes, que foram avaliados através dos seguintes instrumentos: Teste do Mapa do Zoo; Stroop Color and Word Test; Figura Complexa de Rey; e Trail Making Test (parte B). Os resultados mostraram que as provas Mapa do Zoo e Figura Complexa de Rey apresentam um efeito estatisticamente significativo sobre o logit da probabilidade de sofrer obesidade extrema, pelo que défices executivos podem se repercutir num comportamento alimentar mal adaptativo. Estes resultados comprovam a necessidade de identificar de forma precoce os défices executivos. Estas alterações podem ter um impacto no aumento da adiposidade e consequentemente poderão conduzir a obesidade. Desta forma, é possível delinear intervenções mais adequadas, com o intuito de educar as decisões alimentares destes indivíduos

This work aims to verify if the executive functioning can influence the development of morbid obesity. It was used a sample of 48 subjects, which were evaluated by the following neuropsychological assessment tools: Zoo Map; Stroop Interference Test; Rey Complex Figure; and Trail Making Test (part B). The results have shown that the Zoo Map and the Rey Complex Figure have a statistically significant effect on the probability of suffering of morbid obesity, so that executive deficits may lead to a maladaptive eating behavior. These results confirm the need to identify early executive deficits. These changes may have an impact on the increase of adiposity and, consequently, on the evolution of an obesogenic process. Thus, it is possible to delineate more appropriate interventions, in order to educate the eating habits of these individuals