Tau pathology in the dorsal raphe may be a prodromal indicator of Alzheimer's disease.

Protein aggregation in brainstem nuclei is thought to occur in the early stages of Alzheimer's disease (AD), but its specific role in driving prodromal symptoms and disease progression is largely unknown. The dorsal raphe nucleus (DRN) contains a large population of serotonin (5-hydroxytryptamine; 5-HT) neurons that regulate mood, reward-related behavior, and sleep, which are all disrupted in AD. We report here that tau pathology is present in the DRN of individuals 25-80 years old without a known history of dementia, and its prevalence was comparable to the locus coeruleus (LC).

Neuron specific quantitation of Gα expression and signaling in murine brain tissue.

The heterotrimeric G-protein α subunit, Gα, acts to transduce extracellular signals through G-protein coupled receptors (GPCRs) and stimulates adenylyl cyclase mediated production of the second messenger cyclic adenosine monophosphate. Numerous mutations in the GNAL gene, which encodes Gα, have been identified as causative for an adult-onset dystonia. These mutations disrupt GPCR signaling cascades in in vitro assays through several mechanisms, and this disrupted signaling is hypothesized to lead to dystonic motor symptoms in patients.

Deviation scores: An innovative approach to interpreting cognitive test results for individuals with intellectual disabilities.

Background: Students with Intellectual Disability undergo frequent cognitive testing. Testing with this population is limited by insensitivity to relative strengths and weaknesses due to floor effects.

Aim: The study explored the utility of deviation scores via four case studies as a supplement to educational decision-making.

Repeated ethanol exposure and withdrawal alters angiotensin-converting enzyme 2 expression in discrete brain regions: Implications for SARS-CoV-2 neuroinvasion.

Background: People with alcohol use disorder (AUD) may be at higher risk for COVID-19. Angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) are required for cellular entry by SARS-CoV-2, but information on their expression in specific brain regions after alcohol exposure is limited. We sought to clarify how chronic alcohol exposure affects ACE2 expression in monoaminergic brainstem circuits and other putative SARS-CoV-2 entry points.

Diagnostic challenges of prolonged post-treatment clearance of Plasmodium nucleic acids in a pre-transplant autosplenectomized patient with sickle cell disease.

Background: Autosplenectomy, as a result of sickle cell disease, is an important risk factor for severe malaria. While molecular methods are helpful in providing rapid and accurate infection detection and species identification, the effect of hyposplenism on result interpretation during the course of infection should be carefully considered.

Case Presentation: A 32-year old autosplenectomized Nigerian male with severe sickle cell disease was referred to the National Institutes of Health for allogenic hematopoietic stem cell transplant.

Prevalence of hypermucoid Klebsiella pneumoniae among wild-caught and captive vervet monkeys (Chlorocebus aethiops sabaeus) on the island of St. Kitts.

Invasive, hypermucoid Klebsiella pneumoniae causes severe abscess formation in humans and in certain species of nonhuman primates. We conducted a survey of captive and wild-caught African green monkeys, or vervets (Chlorocebus aethiops sabaeus), on the Caribbean island of St. Kitts to assess their carriage rate of Klebsiella spp.

The quantification of absolute myocardial perfusion in humans by contrast echocardiography: algorithm and validation.

Objectives: We sought to test whether myocardial blood flow (MBF) can be quantified by myocardial contrast echocardiography (MCE) using a volumetric model of ultrasound contrast agent (UCA) kinetics for the description of refill curves after ultrasound-induced microsphere destruction.

Background: Absolute myocardial perfusion or MBF (ml.min(-1).