The role of mast cells in atopy: what can we learn from canine models? A thorough review of the biology of mast cells in canine and human systems.

Mast cell research has largely focused on the role of these cells in the early phase of allergic reactions. However, their involvement may well extend beyond this stage, and even reach across nonallergic conditions. Mast cells from different sources have helped advance our knowledge of their biology.

Stress, prefrontal cortex and environmental enrichment: studies on dopamine and acetylcholine release and working memory performance in rats.

The aim of the present study was to investigate whether environmental enrichment changes the effects of acute stress on both the release of dopamine and acetylcholine in the prefrontal cortex (PFC) and working memory performance. Male Wistar rats (3 months of age) were housed in enriched or control conditions during 12 months. Behavioural testing was carried out to assess working memory performance in a delayed alternation task (water escape T-maze).

Stochastic resonance in a linear system: An exact solution.

Multistable systems can exhibit stochastic resonance which is characterized by the amplification of small periodic signals by additive noise. Here we consider a nonmultistable linear system with a multiplicative noise forced by an external periodic signal. The noise is the sum of a colored noise of mean value zero and a noise with a definite sign.

Environmental enrichment reduces the function of D1 dopamine receptors in the prefrontal cortex of the rat.

Environmental enrichment produces changes in spontaneous and psychostimulant-induced motor activity. Dopamine in the prefrontal cortex (PFC), through the activation of D1 receptors, has been suggested to play a role in modulating motor activity. The present study investigated the effects of environmental enrichment on spontaneous motor activity, prefrontal acetylcholine release following local D1 receptor stimulation and D1 receptor expression in the PFC.

Oesophageal motility disorders in type 1 diabetes mellitus and their relation to cardiovascular autonomic neuropathy.

The relationship between cardiovascular autonomic neuropathy (CVAN) and oesophageal dysfunction in diabetes mellitus has not been well established because reports are contradictory. The aim of this study was to assess oesophageal function and its correlation with CVAN in type 1 diabetic patients without oesophageal symptoms. Forty-six type 1 diabetic patients without oesophageal symptoms (DG) and 34 healthy volunteers (CG) were studied.

Stimulation of D2 receptors in the prefrontal cortex reduces PCP-induced hyperactivity, acetylcholine release and dopamine metabolism in the nucleus accumbens.

The aim of the present study was to investigate the effects of stimulation of D2 receptors in the prefrontal cortex (PFC) on spontaneous motor activity and the hyperactivity induced by the psychomimetic phencyclidine (PCP). In addition, the effects of prefrontal D2 stimulation under PCP treatment on dialysate concentrations of acetylcholine, choline, dopamine, DOPAC and HVA in the nucleus accumbens were also investigated. Sprague-Dawley male rats were implanted with guide cannulae to perform bilateral injections into the medial PFC of the D2 agonist quinpirole (1.

Multimedia data capture and management for surgical events: Evaluation of a system.

The objective of this study was to design an electronic form of documentation of surgical procedures, which would include audio and video recording of the entire surgical procedure. Video clips have shown promise for teaching surgical procedures. To date, no systems have been described to fully record video and audio of all events during a surgical procedure.

Environmental enrichment promotes neurogenesis and changes the extracellular concentrations of glutamate and GABA in the hippocampus of aged rats.

The aim of the present study was to investigate the effects of environmental enrichment on the neurogenesis and the extracellular concentrations of glutamate and GABA in the hippocampus of freely moving young and aged rats. Male Wistar rats of 2 (young) and 25 (old) months of age were housed during 8 weeks in an enriched environment; control rats were kept in individual plastic cages during that same period of time. Rats were injected intraperitoneally with bromodeoxyuridine (BrdU; 40 mg/kg; 7 days) during the fourth week of the housing period to detect neurogenesis in the dentate gyrus (DG) of the hippocampus.

Telemedicine and electronic health information for clinical continuity in a mobile surgery program.

Introduction: An intermittent surgical services program in rural Ecuador was able to benefit from close collaboration between surgeons and primary care physicians through the use of telemedicine technologies.

Methods: Inexpensive telemedicine workstations capable of patient documentation, imaging, and video-conferencing at extremely low bandwidth were established in collaborative primary care sites in rural Ecuador. Patients were screened for intermittent surgical services by primary caregivers according to the surgeons' guidelines.

Robotic assistant for laparoscopy.

Background: With the advent of technologies allowing for wider application of minimally invasive surgeries, the integration of telerobotics for mentoring by a surgeon at a remote site will make it possible to include a wider audience in surgical consultations and collaboration.

Materials And Methods: Two surgery research fellows performed 8 laparoscopic cholecystectomies each in a swine model, as the animate portion of the study. Using the Zeus robotic system, a senior surgeon participated as a robotic assistant and consulted remotely.

Bioassay for the identification of natural product-based activators of peroxisome proliferator-activated receptor-gamma (PPARgamma): the marine sponge metabolite psammaplin A activates PPARgamma and induces apoptosis in human breast tumor cells.

Peroxisome proliferator-activated receptors (PPARs), members of the nuclear hormone receptor (NHR) family, are ligand-activated transcription factors. Ligands (agonists) of PPARgamma have been shown to inhibit growth, promote terminal differentiation, and induce apoptosis in human breast tumor cells. A cell-based reporter assay was developed to examine extracts of terrestrial and marine organisms for the ability to activate PPARgamma.

The use of recombinant tissue-type plasminogen activator for the treatment of sudden and chronic hearing loss.

We treated 80 patients with sudden hearing loss and 70 patients with chronic decreasing cochlear function to date with intravenous infusion of a glycoprotein analogous to recombinant tissue-type plasminogen activator (rt-PA): 3 mg dissolved in 250 mg of physiological saline given every 12 hours intravenously. Specifically excluded were patients with known abnormal coagulation. We treated no patient for longer than 20 days.

A study of the effects of cellular telephone microwave radiation on the auditory system in healthy men.

We conducted a study of the effects of mobile cellular telephone microwave radiation on the auditory system in 20 healthy men. After the subjects underwent baseline measurements of transient evoked otoacoustic emission (TEOAE) and auditory brainstem response (ABR), they participated in three sessions of exposure to an electromagnetic field of 900 to 1,800 MHz produced by a cellular phone. Sessions ranged from 15 to 30 minutes in length.

Changes in dopamine and acetylcholine in striatum of the awake rat after chronic treatment with a dopamine uptake blocker.

The effects of chronic treatment with a dopamine uptake blocker on dopamine and acetylcholine extracellular concentrations in striatum of the awake rat was studied. Male Wistar rats received daily injections (i.p.

Sodium enoxaparin treatment of sensorineural hearing loss: an immune-mediated response?

The authors propose the existence of a new entity of autoimmune sensorineural hearing loss on the basis of diagnostic study and treatment experience with a series of 30 patients. Immunological mechanisms play an important role in the pathogenesis and natural course of various inner-ear diseases. Patients may present clinically with symptoms resembling Ménière's disease or even with sudden deafness.

Stereoselective synthesis of (2S,3S,4R,5S)-5-methylpyrrolidine-3,4-diol derivatives that are highly selective alpha-L-fucosidase inhibitors.

N-Phenylaminomethyl benzimidazolyl moieties attached at C-2 of (2S,3S,4R,5S)-5-methylpyrrolidine-3,4-diol increase the potency and selectivity of the inhibitory activity of these systems towards alpha-L-fucosidases.

First Report of Beet pseudo-yellows virus on Cucurbita moschata and C. pepo in Costa Rica.

In early 2004, severe yellowing and chlorosis were observed in field-grown cucurbits in Costa Rica. Symptoms resembled those of the genus Crinivirus (family Closteroviridae), and large populations of whiteflies were observed in the fields and on symptomatic plants. Although the identity of the whiteflies on the curcurbits was not determined, the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) is known to be present in the region from where the samples were obtained.

Effect of H1- and H2-receptor antagonists on the hemodynamic changes induced by the intravenous administration of ketamine in sevoflurane-anesthetized cats.

Objective: The anesthetic ketamine has been reported to cause both an increase of the plasma histamine concentration, notably in cats, and a cardiovascular depression. The latter has been described in humans and in other species. However the relevance of the histamine fluctuation for the ketamine-induced hemodynamic changes has not been determined.

Low-bandwidth telemedicine for pre- and postoperative evaluation in mobile surgical services.

Low-bandwidth telemedicine was used for the pre- and postoperative evaluation of patients treated by a mobile surgery service in remote Ecuador. Realtime and store-and-forward telemedicine was employed, using PCs connected via the ordinary telephone network. Between February 2002 and July 2003, 144 patients were studied preoperatively and 50 postoperatively.

Effects of the metabotropic glutamate receptor agonist, ACPD, on the extracellular concentrations of GABA and acetylcholine in the prefrontal cortex of the rat during the normal process of aging.

The aim of the present study was to investigate the effects of activation of metabotropic glutamate receptors (mGluR) on the extracellular concentrations of GABA and acetylcholine in the prefrontal cortex of freely moving rats of different groups of age. Perfusion, through the microdialysis probe, of the agonist of mGluR, (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (ACPD; 100, 500 and 1000 microM), in the prefrontal cortex of young rats produced a dose-related increase of the dialysate concentrations of GABA. The effects of perfusion of ACPD on the concentrations of GABA were attenuated in middle-aged rats.

Descending necrotizing mediastinitis: ten years' experience.

Descending necrotizing mediastinitis is a rare disease that is usually caused by a spreading, diffuse inflammatory reaction (phlegmon) to an odontogenic infection or peritonsillar abscess. Reported mortality rates range from 25 to 40%. The use of antibiotics and advances in resuscitation procedures and critical care techniques have not essentially improved survival, and an effective treatment has not been clearly established.

Studies on homocysteine plasma levels in Alzheimer's patients. Relevance for neurodegeneration.

Homocysteine (HC) may work inter alia as a Volume Transmission signal since HC is present in the brain and cerebrospinal fluid and binds to NMDA receptors. Furthermore, in cell cultures increased HC formation increases its export. In the present study we have shown that after intravenous injection in intact animals HC penetrates the blood-brain barrier.

Glutamate-dopamine in vivo interaction in the prefrontal cortex modulates the release of dopamine and acetylcholine in the nucleus accumbens of the awake rat.

In the context of the in vivo neurochemical literature this article reviews some recent microdialysis studies in our laboratory of glutamate-dopamine interaction in the prefrontal cortex (PFC) and its possible role in modulating dopamine and acetylcholine release in the nucleus accumbens. A functional glutamate-dopamine interaction in PFC has been reported by microdialysis studies showing that both stimulation and blockade of prefrontal glutamate receptors produce changes of basal and/or stimulated release of dopamine in this area of the brain. These studies suggest that dopamine function in PFC is modulated locally by prefrontal glutamatergic inputs and that glutamate and dopamine can act simultaneously to regulate GABA release in PFC.