Santoshaas6331
We discuss the challenges and successes of the switch to virtual instruction and of teaching pathology content within an integrated medical school curriculum.Animal cognition research often involves small and idiosyncratic samples. This can constrain the generalizability and replicability of a study's results and prevent meaningful comparisons between samples. However, there is little consensus about what makes a strong replication or comparison in animal research. We apply a resampling definition of replication to answer these questions in Part 1 of this article, and, in Part 2, we focus on the problem of representativeness in animal research. Through a case study and a simulation study, we highlight how and when representativeness may be an issue in animal behavior and cognition research and show how the representativeness problems can be viewed through the lenses of, i) replicability, ii) generalizability and external validity, iii) pseudoreplication and, iv) theory testing. Next, we discuss when and how researchers can improve their ability to learn from small sample research through, i) increasing heterogeneity in experimental design, ii) increasing homogeneity in experimental design, and, iii) statistically modeling variation. Finally, we describe how the strongest solutions will vary depending on the goals and resources of individual research programs and discuss some barriers towards implementing them.
Our goal was to determine if features of surgical patients, easily obtained from the medical chart or brief interview, could be used to predict those likely to experience more rapid cognitive decline following surgery.
We analyzed data from an observational study of 560 older adults (≥70 years) without dementia undergoing major elective non-cardiac surgery. NMS-P937 nmr Cognitive decline was measured using change in a global composite over 2 to 36 months following surgery. Predictive features were identified as variables readily obtained from chart review or a brief patient assessment. We developed predictive models for cognitive decline (slope) and predicting dichotomized cognitive decline at a clinically determined cut.
In a hold-out testing set, the regularized regression predictive model achieved a root mean squared error (RMSE) of 0.146 and a model r-square (
) of .31. Prediction of "rapid" decliners as a group achieved an area under the curve (AUC) of .75.
Some of our models could predict persons with increased risk for accelerated cognitive decline with greater accuracy than relying upon chance, and this result might be useful for stratification of surgical patients for inclusion in future clinical trials.
Some of our models could predict persons with increased risk for accelerated cognitive decline with greater accuracy than relying upon chance, and this result might be useful for stratification of surgical patients for inclusion in future clinical trials.
Lewy body-related pathology is commonly observed at autopsy in individuals with dementia, but in vivo biomarkers for α-synucleinopathy are lacking.
Baseline cerebrospinal fluid (CSF) biomarkers, polygenic risk score (PRS) for Parkinson's disease (PRS-PD) and Alzheimer's disease (PRS-AD), longitudinal cognitive scores, and magnetic resonance imaging were measured in 217 participants from the Alzheimer's Disease Neuroimaging Initiative. Linear mixed models were used to find the relationship of CSF biomarkers and the PRS with cognition and cortical atrophy.
Higher PRS-PD and PRS-AD were associated with lower CSF α-synuclein and amyloid beta (Aβ), respectively. Lower CSF α-synuclein and the interaction of CSF α-synuclein and Aβ were associated with lower cognitive scores and global cortical atrophy most prominently in the occipital cortex.
Lower CSF α-synuclein could be a biomarker for α-synucleinopathy, and the simultaneous evaluation of CSF biomarkers for AD and CSF α-synuclein could reveal the independent and interactive effects on cognition and cortical atrophy.
Lower CSF α-synuclein could be a biomarker for α-synucleinopathy, and the simultaneous evaluation of CSF biomarkers for AD and CSF α-synuclein could reveal the independent and interactive effects on cognition and cortical atrophy.This study aimed to determine the performance of a rapid, point-of-care testing device (HemotypeSC)™ for diagnosing sickle cell disease (SCD) relative to 2 commonly-used methods compared to DNA polymerase chain reaction (PCR) as the reference standard. The diagnostic performance of (HemotypeSC)™ in diagnosing SCD and determining various other Hb genotypes relative to high performance liquid chromatography (HPLC) and cellulose acetate Hb electrophoresis in alkaline buffer (CAE) was investigated among 156 participants aged 4 to 23 years in Ekiti, Southwest Nigeria. PCR was considered as the reference method/gold standard. The sensitivity and specificity for SS, SC, AS, AC, and AA genotypes by HemotypeSC and HPLC when compared with PCR, were each 100%. Similarly, their positive and negative predictive values were each 100%. However, sensitivity and specificity for identifying these Hb genotypes by CAE were 100, 100, 96.5, 0, 99.2%, and 99, 100, 92.9, 0, 91.7%. Also, CAE did not identify any of the 2 HbAC individuals that were correctly identified by PCR and both HemotypeSC, and HPLC, thus representing 100% HbAC misdiagnosis. In conclusion, this study shows that HemotypeSC has perfect concordance with PCR and 100% accuracy in diagnosing SCD in the population tested. Its ease of use, accuracy and other attributes make it suitable for use in sub-Saharan Africa for rapid determination of Hb genotypes.Very preterm infants are at risk for germinal matrix hemorrhage- intraventricular hemorrhage (GH-IVH). Severe GH-IVH may cause death or severe neurodevelopmental disability while mild GH-IVH is considered a static, non-progressive disease. This retrospective study aimed to determine if infants with no GH-IVH or mild GH-IVH on initial screening head ultrasound (HUS) advanced to severe GH-IVH. A total of 353 eligible infants with birth gestational age ≤32 0/7 weeks who received a HUS during hospitalization were identified. Of the 343 (97%) infants who had mild GH-IVH (grade II or less) on initial screening, only 4 (1.2%) progressed to severe (grade III or IV). Each of these infants required mechanical ventilation for at least 40 days. Therefore, premature infants who have no GH-IVH or mild GH-IVH on initial routine screening HUS without other risk factors may not require follow-up HUSs. Infants with prolonged mechanical ventilation may require further screening despite reassuring initial HUS findings.
