Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning.

Introduction: New learning results in modulation of intrinsic plasticity in the underlying brain regions. Such changes in intrinsic plasticity can influence allocation and encoding of future memories such that new memories encoded during the period of enhanced excitability are linked to the original memory. The temporal window during which the two memories interact depends upon the time course of intrinsic plasticity following new learning.

The very small angle neutron scattering instrument at the National Institute of Standards and Technology.

A description and the performance of the very small angle neutron scattering diffractometer at the National Institute of Standards and Technology are presented. The measurement range of the instrument extends over three decades of momentum transfer from 2 × 10 to 0.7 Å.

Factors associated with survival in dogs with a histopathological diagnosis of hepatocellular carcinoma: 94 cases (2007-2018).

Background: Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer in dogs. Despite this, relatively few reports of this disease exist pertaining to prognostic factors and outcome.

Aim: To evaluate factors associated with survival in dogs with all subtypes of HCC diagnosed on histopathology.

Apoaequorin differentially modulates fear memory in adult and aged rats.

Introduction: Cognitive deficits during aging are pervasive across species and learning paradigms. One of the major mechanisms thought to play a role in age-related memory decline is dysregulated calcium (Ca ) homeostasis. Aging is associated with impaired function of several calcium-regulatory mechanisms, including calcium-binding proteins that normally support intracellular Ca regulation.

Clinical findings and outcomes of 153 dogs surgically treated for intestinal intussusceptions.

Objective: To describe perioperative characteristics and outcomes of dogs surgically treated for intestinal intussusception.

Study Design: Multi-institutional, retrospective study.

Animals: One hundred fifty-three client-owned dogs with intestinal intussusception.

Age-related memory deficits are associated with changes in protein degradation in brain regions critical for trace fear conditioning.

Brain aging is accompanied by an accumulation of damaged proteins, which results from deterioration of cellular quality control mechanisms and decreased protein degradation. The ubiquitin-proteasome system (UPS) is the primary proteolytic mechanism responsible for targeted degradation. Recent work has established a critical role of the UPS in memory and synaptic plasticity, but the role of the UPS in age-related cognitive decline remains poorly understood.

Heterogeneity of neuronal firing type and morphology in retrosplenial cortex of male F344 rats.

The rodent granular retrosplenial cortex (gRSC) has reciprocal connections to the hippocampus to support fear memories. Although activity-dependent plasticity occurs within the RSC during memory formation, the intrinsic and morphological properties of RSC neurons are poorly understood. The present study used whole-cell recordings to examine intrinsic neuronal firing and morphology of neurons in layer 2/3 (L2/3) and layer 5 (L5) of the gRSC in adult male rats.

Modulation of intrinsic excitability as a function of learning within the fear conditioning circuit.

Experience-dependent neuronal plasticity is a fundamental substrate of learning and memory. Intrinsic excitability is a form of neuronal plasticity that can be altered by learning and indicates the pattern of neuronal responding to external stimuli (e.g.

Layer- and subregion-specific differences in the neurophysiological properties of rat medial prefrontal cortex pyramidal neurons.

Medial prefrontal cortex (mPFC) is critical for the expression of long-term conditioned fear. However, the neural circuits involving fear memory acquisition and retrieval are still unclear. Two subregions within mPFC that have received a lot of attention are the prelimbic (PL) and infralimbic (IL) cortices (e.

Shoulder Injuries in Pediatric Athletes.

Shoulder injuries in pediatric athletes are typically caused by acute or overuse injuries. The developing structures of the shoulder lead to injury patterns that are distinct from those of adult athletes. Overuse injuries often affect the physeal structures of the proximal humerus and can lead to pain and loss of sports participation.

Slipped capital femoral epiphysis and associated hypothyroidism. A review of the literature with two classic case examples.

Slipped capital femoral epiphysis (SCFE) is a relatively common hip disorder often seen in overweight, peripubertal children. Although the exact etiology is uncertain, it is generally accepted that underlying endocrinopathies play a role in the pathogenesis. Hypothyroidism is the endocrine disorder cited most commonly in association with SCFE, and patients often have no history of thyroid dysfunction at the time of presentation.

Trace Fear Conditioning Differentially Modulates Intrinsic Excitability of Medial Prefrontal Cortex-Basolateral Complex of Amygdala Projection Neurons in Infralimbic and Prelimbic Cortices.

Neuronal activity in medial prefrontal cortex (mPFC) is critical for the formation of trace fear memory, yet the cellular mechanisms underlying these memories remain unclear. One possibility involves the modulation of intrinsic excitability within mPFC neurons that project to the basolateral complex of amygdala (BLA). The current study used a combination of retrograde labeling and in vitro whole-cell patch-clamp recordings to examine the effect of trace fear conditioning on the intrinsic excitability of layer 5 mPFC-BLA projection neurons in adult rats.

Hippocampectomy disrupts trace eye-blink conditioning in rabbits.

The role of the hippocampus (HFC) in trace eye-blink conditioning was evaluated using a 100-ms tone conditioned stimulus (CS), a 300- or 500-ms trace interval, and a 150-ms air puff unconditioned stimulus (UCS). Rabbits received complete hippocampectomy (dorsal & ventral), sham lesions, or neocortical lesions. Hippocampectomy produced differential effects in relation to the trace interval used.

Synthesis and biological evaluation of isoprenylated coumarins as potential anti-pancreatic cancer agents.

A series of isoprenylated coumarins has been designed, synthesized, and evaluated against human pancreatic adenocarcinoma cell line PANC-1 under nutrient-rich and nutrient-deprived conditions. The compounds described investigate the effect of isoprenyl chain length and positioning on cell growth inhibition. The majority of these compounds displayed cytotoxicity against PANC-1 cells selectively in the absence of essential amino acids, glucose, and serum, and showed no cytotoxicity under nutrient-rich conditions.

Learning enhances intrinsic excitability in a subset of lateral amygdala neurons.

Learning-induced modulation of neuronal intrinsic excitability is a metaplasticity mechanism that can impact the acquisition of new memories. Although the amygdala is important for emotional learning and other behaviors, including fear and anxiety, whether learning alters intrinsic excitability within the amygdala has received very little attention. Fear conditioning was combined with intracellular recordings to investigate the effects of learning on the intrinsic excitability of lateral amygdala (LA) neurons.

Pretreatment with apoaequorin protects hippocampal CA1 neurons from oxygen-glucose deprivation.

Ischemic stroke affects ∼795,000 people each year in the U.S., which results in an estimated annual cost of $73.

Learning to learn - intrinsic plasticity as a metaplasticity mechanism for memory formation.

"Use it or lose it" is a popular adage often associated with use-dependent enhancement of cognitive abilities. Much research has focused on understanding exactly how the brain changes as a function of experience. Such experience-dependent plasticity involves both structural and functional alterations that contribute to adaptive behaviors, such as learning and memory, as well as maladaptive behaviors, including anxiety disorders, phobias, and posttraumatic stress disorder.

Trace fear conditioning enhances synaptic and intrinsic plasticity in rat hippocampus.

Experience-dependent synaptic and intrinsic plasticity are thought to be important substrates for learning-related changes in behavior. The present study combined trace fear conditioning with both extracellular and intracellular hippocampal recordings to study learning-related synaptic and intrinsic plasticity. Rats received one session of trace fear conditioning, followed by a brief conditioned stimulus (CS) test the next day.

Correlation between sweat glucose and blood glucose in subjects with diabetes.

Background: Sweat contains glucose that can accurately reflect blood glucose. However, skin surface glucose can confound these measurements.

Methods: A perfusion method was used to rapidly harvest sweat from forearm sites on human subjects.

Aging redistributes medial prefrontal neuronal excitability and impedes extinction of trace fear conditioning.

Cognitive flexibility is critical for survival and reflects the malleability of the central nervous system (CNS) in response to changing environmental demands. Normal aging results in difficulties modifying established behaviors, which may involve medial prefrontal cortex (mPFC) dysfunction. Using extinction of conditioned fear in rats to assay cognitive flexibility, we demonstrate that extinction deficits reminiscent of mPFC dysfunction first appear during middle age, in the absence of hippocampus-dependent context deficits.

PF-03814735, an orally bioavailable small molecule aurora kinase inhibitor for cancer therapy.

The Aurora family of highly related serine/threonine kinases plays a key role in the regulation of mitosis. Aurora1 and Aurora2 play important but distinct roles in the G(2) and M phases of the cell cycle and are essential for proper chromosome segregation and cell division. Overexpression and amplification of Aurora2 have been reported in different tumor types, including breast, colon, pancreatic, ovarian, and gastric cancer.

Management of tarsal navicular stress fractures: conservative versus surgical treatment: a meta-analysis.

Purpose: This study was conducted to provide a statistical analysis of previously reported tarsal navicular stress fracture studies regarding the outcomes and effectiveness of conservative and surgical management.

Study Design: Systematic review.

Methods: A systematic review of the published literature was conducted utilizing MEDLINE through Ovid, PubMed, ScienceDirect, and EBSCOhost.

Aging-related changes in calcium-binding proteins in rat perirhinal cortex.

Dysregulation of intracellular calcium homeostasis has been linked to neuropathological symptoms observed in aging and age-related disease. Alterations in the distribution and relative frequency of calcium-binding proteins (CaBPs), which are important in regulating intracellular calcium levels, may contribute to disruption of calcium homeostasis. Here we examined the laminar distribution of three CaBPs in rat perirhinal cortex (PR) as a function of aging.

Differential effects of training intertrial interval on acquisition of trace and long-delay fear conditioning in rats.

Many factors govern conditioning effectiveness, including the intertrial interval (ITI) used during training. The present study systematically varied the training ITI during both trace and long-delay fear conditioning. Rats were trained using one of six different ITIs and subsequently tested for conditioning to the white noise conditioned stimulus (CS) and the training context.