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Biomedical subjects

G Roy

Publications and source records attributed to G Roy.

155 records · Page 9Linked to original sources
PubMedDate not supplied

Local application of neurotensin to abdominal organs triggers cardiovascular reflexes in guinea pigs: possible mechanisms.

Intraabdominal (IAB) injections or topical application of neurotensin (NT) to the serosal surface of the ileum or stomach evoked dose-dependent increases of blood pressure and of heart rate in anesthetized guinea pigs. These effects were markedly reduced by prior animal treatment with a ganglion blocker, alpha and beta adrenoceptor blockers, as well as by exposure of the abdominal organs to lidocaine, a local anesthetic. The blood pressure and heart rate responses to IAB injections or topical application of NT to the ileum or stomach were both inhibited by animal pretreatment with capsaicin. Cervical vagotomy or atropine pretreatment did not prevent or alter the cardiovascular responses to IAB injections of NT. These results suggest the presence in some organs and/or tissues of the abdominal cavity of sympathetic, capsaicin-sensitive sensory nerve fibers which, upon stimulation by NT, produce reflex increases of blood pressure and of heart rate.

Administration, Topical↗
PubMedDate not supplied

Capsaicin-sensitive primary afferents are involved in the hypotensive effect of neurotensin in ganglion-blocked guinea pigs.

The mechanism of the blood pressure (BP)-lowering effect of neurotensin (NT) in the anesthetized, ganglion-blocked guinea pigs was further examined using animals in which the basal BP was artificially raised by an IV infusion of noradrenaline (NA) to overcome the BP-lowering effect of the anesthesia as well as of the ganglion blocker. The animals were also vagotomized and given atropine at the beginning of the experiments to prevent potential baroreceptor-mediated vagal reflexes and/or activation of muscarinic receptors by endogenous acetylcholine. Under these experimental conditions, the IV bolus injections of NT as well as of capsaicin (a reference drug) produced dose-dependent hypotensive effects and variable levels of tachycardia. Omitting the ganglion blocker from the animal drug regimen attenuated but did not abolish the BP-lowering effect of NT and of capsaicin. Neither the hypotensive nor the tachycardic effects of NT and of capsaicin in ganglion-blocked guinea pigs were affected by prior animal treatment with propranolol (a beta adrenoceptor blocker), antihistaminics (mepyramine, cimetidine) or indomethacin (a cyclooxygenase inhibitor). Morphine was found to slightly reduced the hypotensive effect of NT without altering its slight tachycardic effect. Both the hypotensive and tachycardic effects of NT and of capsaicin, in contrast to those elicited by substance P (SP) and calcitonin gene-related peptide (CGRP), were inhibited in ganglion-blocked guinea pigs pretreated four days previously with capsaicin.(ABSTRACT TRUNCATED AT 250 WORDS)

Afferent Pathways↗
PubMedDate not supplied

Diagnostic value of serological markers for celiac disease in diabetic children and adolescents.

OBJECTIVE: To determine the accuracy of antigliadin and antiendomysium antibodies for the diagnosis of celiac disease in diabetic children and adolescents with and without digestive symptoms. STUDY DESIGN: 177 children and adolescents with IDDM aged 15.4 +/- 5.4 years (mean +/- SD). Antigliadin (ELISA) and antiendomysium (IFI) antibodies were measured in 177 and 35 patients, respectively. RESULTS: Seven of 177 patients (3.9%; 95% confidence interval: 1.1-6.7) had celiac disease. The specificities of antiendomysium antibodies test (83%), IgA-antigliadin antibodies test (80%) and IgG-antigliadin antibodies test (90%) and the positive predictive values of these antibodies (55-75%) were lower than those obtained with the combined determination of these antibodies (100%). Negative antibodies and normal mucosa in one determination did not rule out the development of celiac disease later. CONCLUSIONS: The combined determination of antigliadin and antiendomysium antibodies is the test of choice in screening for celiac disease in diabetic patients. The yearly investigation of these antibodies is a reliable method for detecting silent celiac disease in this population.

Adolescent↗
PubMedDate not supplied

Colonic mucosal changes in portal hypertension.

Forty one consecutive patients with portal hypertension (PHT) were evaluated by colonoscopy to study the prevalence, type, extent and predictors of haemorrhoids, colorectal varices, and portal hypertensive colopathy. Specific inquiry and regular follow-up assessed frequency of hematochezia. Twenty five patients with obscure gastrointestinal bleeding without PHT who underwent colonoscopy served as controls. Haemorrhoids were seen in nine of 41 (21.9%) patients with PHT and four of 25 (16%) controls (p = ns). Colorectal varices were seen in 13/41 (31.7%) patients with PHT and none of the controls (p = 0.005). Portal colopathy was present in 15/41 (36.6%) patients with PHT and none of the controls (p = 0.0005). None of the parameters (e.g. aetiology of PHT, Child's class, oesophageal variceal eradication by EST with or without EVL, history of variceal bleeding, grade of oesophageal varices, presence of portal hypertensive gastropathy or gastric varices) predicted the occurrence of colorectal varices and portal hypertensive colopathy. Detection of colorectal varices but not portal hypertensive colopathy was associated with occurrence of hematochezia.

Adult↗
PubMedDate not supplied

[Colonothoracic fistulas: presentation of 2 cases].

Two cases of colothoracic fistulae are reported. The first one is secondary to pulmonary actinomycosis, the second to complicated colic diverticulitis. The etiologies of colothoracic fistulae are multiple and can be divided in intrathoracic or intraabdominal origin. The treatment includes: effective intravenous antibiotherapy, colic resection of the concerned portion and thoracic drainage.

Actinomycosis↗
PubMedDate not supplied

[Are day care children often absent because of illness?].

Over an 18-month period, we observed 759 children attending eight day care centres in the Quebec City area to determine the rate of absenteeism due to illness in day care centres. 481 children were absent for a mean duration of 4.1 days. The absenteeism rate was 5.6 days out of a possible 1 000 days of attendance and did not vary with day care centre or age.

Absenteeism↗
PubMedDate not supplied

[Delivery of public health services. Proposal for a frame of reference].

This article proposes a framework for the delivery of public health services by the health care system. Considering the many factors associated with a population's health status and well-being, health care systems must provide public health services in addition to clinical preventive health care services. Public health services are distinctive in that they are supplied in response to community as opposed to individual needs. The delivery of public health services is carried out, in partnership with groups and organizations, through the use of strategies that enable, advocate and educate. These strategies, taking place at the earliest possible moment in the natural history of problems, act as catalysts in the process of change towards health and well-being.

Canada↗
PubMedDate not supplied

[Vaccination against influenza in elderly persons: some current presumptions].

A telephone survey in March 1994 revealed that only 70% of 185 persons surveyed aged 65 and over were offered influenza vaccine during the last flu shot campaign; the sample was taken among non-institution residents of the Quebec City area who were likely to have regular health professional contact. Misinformation concerning influenza infection and vaccine remains widespread: 30% of the people surveyed still believe that the vaccine can transmit the virus and 21% consider the vaccine ineffective. Incorrect beliefs are significantly more prevalent among the unvaccinated population: 12% stated that they were allergic to the vaccine; in fact, true allergies are rare. Health professionals should recognize that elderly people, though in regular contact with the health care system, may not have been offered the influenza vaccine and may have inadequate information or incorrect beliefs regarding influenza and its preventability.

Aged↗