J Cereb Blood Flow Metab
December 2024
Whether top-down feedback modulates perception has deep implications for cognitive theories. Debate has been vigorous in the domain of spoken word recognition, where competing computational models and agreement on at least one diagnostic experimental paradigm suggest that the debate may eventually be resolvable. Norris and Cutler (2021) revisit arguments against lexical feedback in spoken word recognition models.
View Article and Find Full Text PDFNeurons communicate with vasculature to regulate blood flow in the brain, a process maintained by the neurovascular unit (NVU). This interaction, termed neurovascular coupling, is believed to involve astrocytes or molecules capable of traversing the astrocytic endfeet. The precise mechanism, however, remains elusive.
View Article and Find Full Text PDFOsteomyelitis of the skull is a particularly life-threatening condition. Infections are usually at the base of the skull and typically occur following dissemination from another site, such as the external auditory canal. Typical organisms include and species.
View Article and Find Full Text PDFBreast cancer is a leading cause of cancer death in the United States, with an increasing incidence in recent years. Paraneoplastic syndromes are uncommon but increasingly recognized complications of many types of cancer, including breast cancer. Here, we describe a case of a patient presenting with confounding symptoms, who was diagnosed with breast cancer and believed to have a paraneoplastic syndrome despite a negative paraneoplastic panel.
View Article and Find Full Text PDFThe microvascular inflow tract, comprising the penetrating arterioles, precapillary sphincters and first-order capillaries, is the bottleneck for brain blood flow and energy supply. Exactly how aging alters the structure and function of the microvascular inflow tract remains unclear. By in vivo four-dimensional two-photon imaging, we reveal an age-dependent decrease in vaso-responsivity accompanied by a decrease in vessel density close to the arterioles and loss of vascular mural cell processes, although the number of mural cell somas and their alpha smooth muscle actin density were preserved.
View Article and Find Full Text PDFSarcoidosis is a well-characterized inflammatory disease that affects multiple organ systems and can have long-term devastating outcomes if not identified and treated appropriately. The disease is most prevalent among young to middle-aged African American women. It most commonly presents with pulmonary involvement, though there are reported cases of sarcoidosis without pulmonary involvement.
View Article and Find Full Text PDFTo date, scholars have focused a considerable amount of effort on developing valid measures of leader-member exchange (LMX). Although useful, it is unclear whether this proliferation in measurement is warranted. Specifically, although perhaps meaningful conceptual distinctions are made when developing new LMX measures, it is unclear whether these measures differ sufficiently from previously established measures.
View Article and Find Full Text PDFLearning is a critical behavioral process that is influenced by many neurobiological systems. We and others have reported that acetylcholinergic signaling plays a vital role in learning capabilities, and it is especially important for contextual fear learning. Since cholinergic signaling is affected by genetic background, we examined the genetic relationship between activity levels of acetylcholinesterase (AChE), the primary enzyme involved in the acetylcholine metabolism, and learning using a panel of 20 inbred mouse strains.
View Article and Find Full Text PDFComp Biochem Physiol A Mol Integr Physiol
April 2021
The neurovascular coupling ensures that cerebral activity is matched by the relevant blood flow. The control of the blood flow is mediated by capillaries and by the precapillary aterioles. It is the tone of the mural cells, which include pericytes, smooth muscle cells and cells with intermediate phenotypes between pericytes and smooth muscle cells, that determine the the diameter of the blood vessels and consequently the flow.
View Article and Find Full Text PDFCholera is a well known cause of significant disease, particularly in resource-poor nations, but it is very rare in developed countries. The morbidity and mortality of cholera is resultant from large-volume diarrhea, hypovolemia, and electrolyte derangement. In the following case, a 60-year-old man with no recent travel history presented to the emergency department with muscle cramping, abdominal pain, and gastrointestinal distress.
View Article and Find Full Text PDFActive nerve cells release vasodilators that increase their energy supply by dilating local blood vessels, a mechanism termed neurovascular coupling and the basis of BOLD functional neuroimaging signals. Here, we reveal a mechanism for cerebral blood flow control, a precapillary sphincter at the transition between the penetrating arteriole and first order capillary, linking blood flow in capillaries to the arteriolar inflow. The sphincters are encircled by contractile mural cells, which are capable of bidirectional control of the length and width of the enclosed vessel segment.
View Article and Find Full Text PDFBackground: Patient-derived xenograft (PDX) models are in vivo models of human cancer that have been used for translational cancer research and therapy selection for individual patients. The Jackson Laboratory (JAX) PDX resource comprises 455 models originating from 34 different primary sites (as of 05/08/2019). The models undergo rigorous quality control and are genomically characterized to identify somatic mutations, copy number alterations, and transcriptional profiles.
View Article and Find Full Text PDFContact with environmental microbes are arguably the most common species interaction in which any animal participates. Studies have noted diverse relationships between hosts and resident microbes, which can have strong consequences for host development, physiology, and behavior. Many of these studies focus specifically on pathogens or beneficial microbes, while the benign microbes, of which the majority of bacteria could be described, are often ignored.
View Article and Find Full Text PDFAims: Abnormal intracellular Ca2+ cycling contributes to triggered activity and arrhythmias in the heart. We investigated the properties and underlying mechanisms for systolic triggered Ca2+ waves in left atria from normal and failing dog hearts.
Methods And Results: Intracellular Ca2+ cycling was studied using confocal microscopy during rapid pacing of atrial myocytes (36 °C) isolated from normal and failing canine hearts (ventricular tachypacing model).
The derivation of functional cardiomyocytes (CMs) from human embryonic stem cells (hESCs) represents a unique way of studying human cardiogenesis, including the development of CM subtypes. In this study, we investigated the development and organization of hESC-derived cardiomyocytes (hESC-CMs) and examined how the expression levels of CM subtypes correspond to human in vivo cardiogenesis. Beating clusters were used to determine cardiac differentiation, which was evaluated by the expression of cardiac genes GATA4 and TNNT2 and subcellular localization of GATA4 and NKX2.
View Article and Find Full Text PDFBackground: Undifferentiated abdominal pain is a common condition encountered in the emergency department. While a patient's age, risk factors, and comorbidities often aid in risk stratification and guide emergency department evaluation, atypical presentations of serious disease may still occur suddenly in young otherwise healthy patients.
Case Report: In this vignette we discuss a case of spontaneous, atraumatic renal rupture with large retroperitoneal hemorrhage (Wunderlich's Syndrome) in a 22year old male.
Bacteriophages Phinally and Vivi2 were isolated from soil from Pittsburgh, Pennsylvania, USA, using host Gordonia terrae 3612. The Phinally and Vivi2 genomes are 59,265 bp and 59,337 bp, respectively, and share sequence similarity with each other and with GTE6. Fewer than 25% of the 87 to 89 putative genes have predictable functions.
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