Engagement of visual fixation suppresses sensory responsiveness and multisensory integration in the primate superior colliculus.

Neurons in the intermediate and deep layers of the superior colliculus (SC) often exhibit sensory-related activity in addition to discharging for saccadic eye movements. These two patterns of activity can combine so that modifications of the sensory response can lead to changes in orienting behaviour. Can behavioural factors, however, influence sensory activity? In this study of rhesus monkeys, we isolate one behavioural factor, the state of visual fixation, and examine its influences on sensory processing and multisensory integration in the primate SC.

Anterior ectosylvian cortical projections to the rostral suprasylvian multisensory zone in cat.

Recent studies have shown that the anterior ectosylvian sulcal cortex (AESc) and the rostral suprasylvian sulcal cortex (RSSSc) of the cat play integral roles in behavioral and collicular responses to multisensory stimuli. However, substantially more multisensory superior colliculus (SC) neurons are affected by blockade of the AESc than the RSSSc. Although both cortical regions project directly to the SC, a possible explanation for this differential effect is that the AESc may also relay an indirect corticotectal signal via the RSSSc that is reduced when the AESc is deactivated.

Exploring the relationship between surrogates and clinical outcomes: analysis of individual patient data vs. meta-regression on group-level summary statistics.

There has been an increasing interest in exploring the relationship between a surrogate and a clinical outcome. Two different statistical approaches have been taken by researchers to quantify the treatment effect on the clinical outcome explained by the surrogate endpoint: 1) analysis based on individual patient data (IPD), and 2) meta-regression based on summary statistics from published literature. An analysis based on IPD models the associations between the surrogate and clinical outcome for patients directly and is able to adjust for patient-level covariates.

NADPH oxidase activity is essential for Keap1/Nrf2-mediated induction of GCLC in response to 2-indol-3-yl-methylenequinuclidin-3-ols.

Glutamate cysteine ligase, the rate-limiting enzyme for the synthesis of glutathione, represents an important component of chemoprevention paradigms. GCLC and GCLM, the genes encoding glutamate cysteine ligase subunits, are induced by indoles, such as indomethacin. Novel functionalized indole analogues and other structurally related compounds were synthesized and used for a comparative structure analysis of GCLC induction.

A comparison of the distribution of GABA-ergic neurons in cortices representing different sensory modalities.

It is well known that sensory receptive field properties are shaped by inhibitory processes. Given the physiological and perceptual distinctions among the different sensory modalities, it might be expected that the contribution of GABA-ergic inhibition to the process would vary from area to area, depending on the sensory modality represented. Furthermore, as receptive field properties become progressively more complex at higher cortical levels, differences in the inhibitory contributions to these computations would be reflected in differences in GABA-ergic neuronal distribution.

The influence of chemosensory input and gonadotropin releasing hormone on mating behavior circuits in male hamsters.

Chemosensory input is important for mating behavior in male hamsters. Chemosignals found in female hamster vaginal fluid activate regions of the brain that receive input from the vomeronasal/accessory olfactory system and are important for mating behavior. Mating or exposure to these chemosignals produces increased Fos protein expression in the amygdala, bed nucleus of the stria terminalis, and medial preoptic area (MPOA).

Pre-exposure to female chemosignals or intracerebral GnRH restores mating behavior in naive male hamsters with vomeronasal organ lesions.

Chemosensory input is essential for mating in male hamsters and the vomeronasal organ is critical to mating in naive males. In studies to investigate the convergence of vomeronasal chemosensory input and the neurohormone gonadotrophin releasing hormone (GnRH), we have unexpectedly found that pre-exposure to pheromone-containing chemosignals from female hamsters will also eliminate mating deficits normally seen in naive male hamsters with vomeronasal organs removed (VNX). In the present studies, naive-intact and naive-VNX male hamsters were given intracerebroventricular injections of GnRH or saline and exposed to female pheromones found in hamster vaginal fluid (HVF) or to water 40 min prior to a 5 min mating test.

X-ray technologists' reproducibility from automated measurements of the medial tibiofemoral joint space width in knee osteoarthritis for a multicenter, multinational clinical trial.

Objective: To determine the reproducibility of x-ray technologists, 26 in North America (NA), 24 in Europe (EU), in reliably repositioning patient's osteoarthritic (OA) knees, from computerized measurements of minimum joint space width (JSW) and reproducibility in joint repositioning, during their training for the clinical trial.

Methods: Technologists from 12 NA and 12 EU clinical radiology units received identical training, at one site on each continent, in performing the fluoroscopically assisted semiflexed knee examination and in quality control criteria (QCC) for film acceptance. Subjects recruited were 129 in NA and 70 in EU, with both knees radiographed for some subjects.

Chemoarchitecture of GABAergic neurons in the ferret superior colliculus.

gamma-Aminobutyric acid (GABA)ergic neurons are thought to play a key role both in visual processing and in the complex sensory-motor transformations that take place in the mammalian superior colliculus. To understand the organization of GABAergic neurons in the ferret superior colliculus, we applied antisera to several markers of GABAergic function, including GABA, two isoforms of its synthetic enzyme glutamic acid decarboxylase (GAD-65 and GAD-67), and the GABA transporter, GAT-1. We also applied antisera to several calcium binding proteins (calbindin [CB], calretinin [CR], and parvalbumin [PV]) and neuronal nitric oxide synthase (NOS), chemical markers that colocalize with GABA in some areas of the central nervous system.

Herbal nutriceuticals: a primer for dentists and dental hygienists.

Herbs have been in use for centuries to prevent and control disease. In recent history demand by the public for herbal supplements has created a multimillion-dollar industry. Herbal extracts are effective because they interact with specific chemical receptors within the body and are in a pharmacodynamic sense, drugs themselves.

Spin-state alteration from sterically enforced ligand rotation in bis(indenyl)chromium(II) complexes.

The rotational orientation of cyclopentadienyl rings usually has no effect on d-orbital energy levels and splitting in transition metal complexes. With related but less symmetrical carbocyclic ligands, however, the magnetic properties of the associated complexes can be altered by the alignment of the ligands. Examples of this effect are found in substituted organochromium(II) bis(indenyl) complexes.

Redox signaling of cardiac HSF1 DNA binding.

Experiments involving chemical induction of the heat shock response in simple biological systems have generated the hypothesis that protein denaturation and consequential binding of heat shock transcription factor 1 (HSF1) to proximal heat shock elements (HSEs) on heat shock protein (hsp) genes are the result of oxidation and/or depletion of intracellular thiols. The purpose of the present investigation was to determine the role of redox signaling of HSF1 in the intact animal in response to physiological and pharmacological perturbations. Heat shock and exercise induced HSF1-HSE DNA binding in the rat myocardium (P < 0.

On the neuronal basis for multisensory convergence: a brief overview.

For multisensory stimulation to effect perceptual and behavioral responses, information from the different sensory systems must converge on individual neurons. A great deal is already known regarding processing within the separate sensory systems, as well as about many of the integrative and perceptual/behavioral effects of multisensory processing. However, virtually nothing is known about the functional architecture that underlies multisensory convergence even though it is an integral step to this processing sequence.

Experience facilitates vomeronasal and olfactory influence on Fos expression in medial preoptic area during pheromone exposure or mating in male hamsters.

Chemosensory stimuli are essential for mating in male hamsters but either main olfactory or vomeronasal input is sufficient in sexually experienced males. Activation in central chemosensory pathways and medial preoptic area, after stimulation with female chemosignals or after mating, was estimated by counting neurons expressing Fos protein in experienced and naive males, with or without vomeronasal organ lesions. Regions counted included main and accessory olfactory bulbs, corticomedial amygdala, bed nucleus stria terminalis and medial preoptic area.

Redox-sensitive interaction between KIAA0132 and Nrf2 mediates indomethacin-induced expression of gamma-glutamylcysteine synthetase.

Exposure of HepG2 cells to nonsteroidal anti-inflammatory drugs (i.e., indomethacin and ibuprofen; NSAIDs) as well as resveratrol, caused increased expression of the mRNAs coding for the catalytic (Gclc) and modifier (Gclm) subunits of the glutathione synthetic enzyme, gamma-glutamylcysteine synthetase.

A method to assess the proportion of treatment effect explained by a surrogate endpoint.

Randomized clinical trials are the standard for evaluating new drugs, devices and procedures. Traditional clinical trials entail not only considerable expense, but require considerable time to complete. The use of surrogate endpoints constitutes an effort to control cost and completion time for clinical trials.

Vomeronasal organ: electrical stimulation activates Fos in mating pathways and in GnRH neurons.

Electrical stimulation of the vomeronasal organ in male hamsters activated Fos expression in neurons of the chemosensory pathways, as in experiments where animals were stimulated with female chemical stimuli. Fos was also activated in gonadotropin hormone releasing hormone (GnRH, or LHRH) neurons in the rostral medial preoptic region of the brain, a possible substrate for GnRH influence on chemosensory-dependent reproductive behavior.

Risk factors for frequent and severe hypoglycemia in type 1 diabetes.

Objective: To determine the risk of frequent and severe hypoglycemia and the associated demographic and clinical risk factors.

Research Design And Methods: Demographic and diabetes self-management factors were measured in 415 subjects followed prospectively for 4-6.5 years of type 1 diabetes duration as participants in a population-based incident cohort.

Organization of the neurons of origin of the descending pathways from the ferret superior colliculus.

The superior colliculus (SC), through its descending projections to the brainstem and spinal cord, is involved in initiating sensory-driven orienting behaviors. Ferrets are carnivores that hunt both above and below ground using visual (and auditory) cues in the daylight but non-visual cues in darkness and in subterranean environments. The present investigation sought to determine whether the ferret SC shows organizational features similar to those found in other visually dominant animals (e.

The ferret's vomeronasal organ and accessory olfactory bulb: effect of hormone manipulation in adult males and females.

The male ferret, a carnivore, was recently shown to possess a vomeronasal organ (VNO). We compared the morphology of the VNO and its associated accessory olfactory bulb (AOB) in male and female ferrets that were killed in adulthood. The volume and surface area of the VNO neuroepithelium were similar in adult gonadectomized male and female ferrets regardless of whether they were treated with testosterone propionate (TP) or oil vehicle.

The influence of stimulus properties on multisensory processing in the awake primate superior colliculus.

Multisensory integration is a process whereby information converges from different sensory modalities to produce a response that is different from that elicited by the individual modalities presented alone. A neural basis for multisensory integration has been identified within a variety of brain regions, but the most thoroughly examined model has been that of the superior colliculus (SC). Multisensory processing in the SC of anaesthetized animals has been shown to be dependent on the physical parameters of the individual stimuli presented (e.

Human vomeronasal organ function: a critical review of best and worst cases.

The human vomeronasal organ (VNO) has been the subject of some interest in the scientific literature and of considerable speculation in the popular science literature. A function for the human VNO has been both dismissed with ridicule and averred with conviction. This question of VNO function has been needlessly tied to the separate question of whether there is any place for pheromone communication among humans, a topic that is itself bogged down in conflicting definitions.

Responses to innocuous, but not noxious, somatosensory stimulation by neurons in the ferret superior colliculus.

The intermediate and deep layers of the superior colliculus (SC) are known for their role in initiating orienting behaviors. To direct these orienting functions, the SC of some animals (e.g.