Search results for "Homeostasis"
showing 10 items of 630 documents
Transcranial Doppler ultrasound study of the effects of nitrous oxide on cerebral autoregulation during neurosurgical anesthesia: a randomized contro…
2003
Object. Nitrous oxide has an adverse effect on cerebrovascular hemodynamics. Increased intracranial pressure, cerebral blood flow (CBF), cerebral metabolic rate of O2 (CMRO2), and reduced autoregulation indices have been reported, but their magnitudes are still being debated. This study was designed to evaluate the effect of N2O on CBF and autoregulatory indexes during N2O—sevoflurane anesthesia in a prospective randomized controlled series of patients. Methods. Two groups of 20 patients were studied on the basis of the use of N2O in the anesthetic gas mixture. The transient hyperemic response test, which relies on transcranial Doppler ultrasound techniques, was used to assess cerebral hemo…
Autoregulatory role of interleukin-10 in hepatitis C patients treated with IFN-alpha.
2004
Interferon-alpha2 (IFN-alpha2) is used as standard treatment of patients with chronic hepatitis C (cHCV), but little is known about the immunomodulatory effects of this cytokine in vivo. We have studied immunologic parameters in freshly isolated peripheral blood mononuclear cells (PBMC) of 26 patients with cHCV 12 h before and 12 h after the first s.c. injection of 5-6 MU IFN-alpha2. In PBMC obtained after IFN injection, a substantial increase in IL-10 production after antigen-specific and nonspecific stimulation was observed, whereas IFN-gamma production and proliferation were significantly diminished compared with PBMC obtained before IFN injection. Patients were stratified according to s…
Perilipin polymorphism interacts with saturated fat and carbohydrates to modulate insulin resistance
2010
Macronutrient intakes and genetic variants have been shown to interact to alter the risk of insulin resistance, but replication of gene-nutrient interactions across independent populations may be difficult to achieve. Saturated fat and carbohydrate were previously shown to interact with genotype for insulin resistance for a variant of perilipin (PLIN), the major adipocyte-associated protein and a regulator of adipocyte metabolism. We investigated the same interaction for PLIN 11482G>A (rs894160) on insulin resistance in US men(n=462) and women(n=508) (mean ±SD, 49±16 years). In multivariate linear regression models, we found a significant (PA for HOMA-IR (homeostasis model assessment of ins…
An Emerging Method to Assess Tear Film Spread and Dynamics as Possible Tear Film Homeostasis Markers
2021
This study aims to assess the performance of an analysis method to measure in vivo the movement speed of tear film particles post-blink as a measure of tear film spreading. Ocular surface parameter...
Reduced Threshold for Inhibitory Homeostatic Responses in Migraine Motor Cortex? A tDCS/TMS Study
2014
Background and Objective Neurophysiological studies in migraine have reported conflicting findings of either cortical hyper- or hypoexcitability. In migraine with aura (MwA) patients, we recently documented an inhibitory response to suprathreshold, high-frequency repetitive transcranial magnetic stimulation (hf-rTMS) trains applied to the primary motor cortex, which is in contrast with the facilitatory response observed in the healthy subjects. The aim of the present study was to support the hypothesis that in migraine, because of a condition of basal increased cortical responsivity, inhibitory homeostatic-like mechanisms of cortical excitability could be induced by high magnitude stimulati…
Heart and Skeletal Muscles: Linked by Autonomic Nervous System.
2019
Background Resting sympathetic hyperactivity and impaired parasympathetic reactivation after exercise have been described in patients with heart failure (HF). However, the association of these autonomic changes in patients with HF and sarcopenia is unknown. Objective The aim of this study was to evaluate the impact of autonomic modulation on sarcopenia in male patients with HF. Methods We enrolled 116 male patients with HF and left ventricular ejection fraction < 40%. All patients underwent a maximal cardiopulmonary exercise testing. Maximal heart rate was recorded and delta heart rate recovery (∆HRR) was assessed at 1st and 2nd minutes after exercise. Muscle sympathetic nerve activity (MSN…
Association Study of Nonsynonymous Single Nucleotide Polymorphisms in Schizophrenia
2010
Genome-wide association studies using several hundred thousand anonymous markers present limited statistical power. Alternatively, association studies restricted to common nonsynonymous single nucleotide polymorphisms (nsSNPs) have the advantage of strongly reducing the multiple testing problem, while increasing the probability of testing functional single nucleotide polymorphisms (SNPs).We performed a case-control association study of common nsSNPs in Galician (northwest Spain) samples using the Affymetrix GeneChip Human 20k cSNP Kit, followed by a replication study of the more promising results. After quality control procedures, the discovery sample consisted of 5100 nsSNPs at minor allel…
Increased expression of the homeostatic chemokines CCL19 and CCL21 in clinical and experimental Rickettsia conorii infection
2013
Background: Based on their essential role in concerting immunological and inflammatory responses we hypothesized that the homeostatic chemokines CCL19 and CCL21 may play a pathogenic role in rickettsiae infection. Methods: Serum levels of CCL19 and CCL21 in patients with R. africae and R. conorii infection were analyzed by enzyme immunoassays. Lungs from R. conorii infected mice were examined for CCL19, CCL21 and CCR7 expression by immunohistochemistry. Results: We found that patients with R. africae infection (n = 15) and in particular those with R. conorii infection (n = 16) had elevated serum levels of CCL19 on admission, with a decline during follow-up. While a similar pattern was seen …
Night-Time Shift Work and Related Stress Responses: A Study on Security Guards
2020
Work-related stress can induce a break in homeostasis by placing demands on the body that are met by the activation of two different systems, the hypothalamic&ndash
Serial Measurement of Static and Dynamic Cerebrovascular Autoregulation After Brain Injury
2011
In patients with neuronal injury, the knowledge of the status of cerebrovascular autoregulation can help to optimize the management of the cerebral perfusion pressure. This study characterizes dynamic and static cerebrovascular autoregulation during the first 7 days after severe traumatic brain injury or intracranial hemorrhage.After approval from the IRB, 16 patients were studied. Cerebral blood flow velocity (CBFV) was measured daily for the assessment of dynamic (10 patients) and static (16 patients) cerebrovascular autoregulation in both the middle cerebral arteries using the transcranial Doppler sonography. Dynamic cerebrovascular autoregulation (dAR) was measured using the cuff-deflat…