COVID-19 and Poverty in South America: the Mental Health Implications.

The COVID-19 pandemic caused by the SARS-CoV-2 virus made governments across the world announce country-wide lockdowns suspending all activities and banning travels. This affected the lives of millions of people across all the continents in the world, including South America. The low-income classes were most affected by the lockdowns as many lost their only source of income. In addition, the uncertainty of the disease and its deadly nature along with lack of access to correct information led to a deterioration of the mental health of the low-income and indigenous groups in South America. The low-income population has little chance of gaining access to proper mental healthcare as many healthcare systems collapsed due to the nature of the pandemic. A good number of them faced short-term mental effects such as anxiety and panic attacks as well as long-term effects of depression. Proper steps must be taken to maintain and help the most vulnerable sections of the population. The pandemic along with the widespread poverty-stricken regions in the country have affected the population of the country. This article assesses the impact of COVID-19 on the poor and low-income population of the South American continent and the impact it has had on their mental health. It also reviews the recommended steps that can be taken to improve the situation and help the affected people.

Structure-based functional analysis of BRCA1 RING domain variants: Concordance of computational mutagenesis, experimental assay, and clinical data.

A significant impediment to the improvement of clinical outcomes in treating breast and ovarian cancers rests with the lack of available interpretations for BRCA1 variants of unknown significance. Two research groups recently implemented large-scale functional assays for quantifying effects of single missense mutations on homology-directed DNA repair activity of BRCA1 variants, which is critical for tumor suppression and strongly correlates with cancer risk, and their results are significantly concordant with each other as well as with known pathogenic and benign variant clinical data. In this work, we implemented an established computational mutagenesis procedure to characterize structural impacts of single residue replacements to the BRCA1 RING domain. The computational data showed similarly strong concordance with known clinical data as well as with experimental data from both functional assays. Predictions made by models trained on our computational data offer a complementary and orthogonal approach for classifying all remaining unexplored BRCA1 RING domain variants.

Preoperative Vitamin K Reduces Blood Transfusions at Time of Left Ventricular Assist Device Implant.

BACKGROUND: Congestive heart failure patients have hepatic congestion and abnormal coagulation profiles, increasing perioperative bleeding at time of ventricular assist device implantation. This study examined the impact of the preoperative administration of vitamin K on perioperative blood transfusion requirements. METHODS: Retrospectively, 190 patients met inclusion criteria. Patients received no vitamin K (n = 62) or two 10-mg doses of intravenous vitamin K (n = 128) in the 24 hours before assist device implantation. Primary end points included transfusion requirements and reexploration rates for bleeding. Secondary outcomes were pump thrombosis and in-hospital mortality. RESULTS: Baseline characteristics were similar between the 2 groups, with slight differences (not statistically significant) noted in the Interagency Registry for Mechanically Assisted Circulatory Support profile and total bilirubin levels. The only significant difference noted was the year of implantation (P < .001). Blood product usage was significantly lower in the vitamin K group compared to the no vitamin K group (P < .001). Higher rates of reexploration for bleeding (29.7% vs 13.6%, P = .023) and death at hospital discharge (16.2% vs 2.8%, P = .004) were noted for the no vitamin K group compared with the vitamin K group. After adjusting for age, sex, race, body mass index, Interagency Registry for Mechanically Assisted Circulatory Support profile, total bilirubin, surgeon, and year of operation, reexploration rates and death did not achieve statistical significance. No statistically significant difference was observed in stroke and pump thrombosis rates between the 2 groups. CONCLUSIONS: Preoperative vitamin K administration may help reduce blood product use without any increased risk for strokes or pump thrombosis.

Right Heart Failure in Different Left Ventricular Assist Devices: Single-Center Experience.

Background: Right heart failure (RHF) following left ventricular assist device (LVAD) implantation increases morbidity and mortality for those who develop this complication. The purpose of this study was to assess the differences in incidence of RHF and outcomes between 2 types of continuous-flow LVADs at a single center. Methods: From January 2012 through June 2016, 184 patients were implanted with a continuous-flow LVAD (161 patients with the HeartMate II and 23 patients with the HeartWare device) either as a bridge to transplant or as destination therapy. Preoperative demographics, medical history, laboratory values, hemodynamics, and device type were analyzed to determine the variables associated with RHF and mortality. Results: Preoperative variables between the 2 groups were homogeneous. Most patients were Interagency Registry for Mechanically Assisted Circulatory Support profile 1 or 2 (92%) and New York Heart Association class IV (81%). More patients in the HeartMate II group had the indication of destination therapy (54% vs 30%), while more patients in the HeartWare group were implanted as bridge to transplant (70% vs 46%). RHF occurred in 57% of HeartWare patients compared to 16% of patients who received the HeartMate II (P=0.0001). After propensity score analysis, patients receiving the HeartWare device had increased odds for RHF (P=0.0013) and renal failure requiring dialysis (P=0.0135). The HeartMate II patient survival rate exceeded the HeartWare patient survival rate at 1 year (82.1% vs 67.2%) and at 2 years (74.6% vs 61.7%), but this difference did not achieve statistical significance (log-rank P=0.087). Conclusion: These results indicate that device type may affect RHF incidence and mortality. Studies at other centers are needed to replicate these findings.

Massive air embolism resulting in ischemic stroke after left ventricular assist device implantation.

We present the first case of ischemic stroke secondary to massive air embolus during implantation of a left ventricular assist device (LVAD). The patient experienced a suction event at the time of aortic cannula removal. Despite the use of all standard deairing techniques and flooding the operative field with continuous-flow carbon dioxide, a significant amount of air was delivered into the ascending aorta through the LVAD pump.

Fitness of unregulated human Ras mutants modeled by implementing computational mutagenesis and machine learning techniques.

Ras proteins play a pivotal role as oncogenes by participating in diverse signaling events, including those linked to cell growth, differentiation, and proliferation. Using experimental fitness data and implementing artificial intelligence and a computational mutagenesis technique, we developed models that reliably predict fitness for all single residue mutants of H-ras proto-oncogene protein p21. The computational mutagenesis generated a feature vector of protein structural changes for each variant, and these data correlated well with fitness. Random forest classification and tree regression machine learning algorithms were implemented for training predictive models. Cross-validations were used to evaluate model performance, and control experiments were performed to assess statistical significance. Classification models revealed a balanced accuracy rate as high as 82%, with a Matthew's correlation of 0.63, and an area under ROC curve of 0.90. Similarly, regression models displayed Pearson's correlation reaching 0.79. On the other hand, control data sets led to performance values consistent with random guessing. Comparisons with several related state-of-the-art methods reflected favorably on our trained models. This H-Ras proof-of-principle study suggests a complementary approach for understanding mechanisms with which other proteins are involved in oncogenesis, including related Ras isoforms, and for providing useful insights into designing future diagnostic and treatment modalities.