PubMed Health⌕ Search

Biomedical subjects

R Cyr

Publications and source records attributed to R Cyr.

13 recordsLinked to original sources
PubMed2001

Use of abnormal preprophase bands to decipher division plane determination.

Many premitotic plant cells possess a cortical preprophase band of microtubules and actin filaments that encircles the nucleus. In vacuolated cells, the preprophase band is visibly connected to the nucleus by a cytoplasmic raft of actin filaments and microtubules termed the phragmosome. Typically, the location of the preprophase band and phragmosome corresponds to, and thus is thought to influence, the location of the cell division plane. To better understand the function of the preprophase band and phragmosome in orienting division, we used a green fluorescent protein-based microtubule reporter protein to observe mitosis in living tobacco bright yellow 2 cells possessing unusual preprophase bands. Observations of mitosis in these unusual cells support the involvement of the preprophase band/phragmosome in properly positioning the preprophase nucleus, influencing spindle orientation such that the cytokinetic phragmoplast initially grows in an appropriate direction, and delineating a region in the cell cortex that attracts microtubules and directs later stages of phragmoplast growth. Thus, the preprophase band/phragmosome appears to perform several interrelated functions to orient the division plane. However, functional information associated with the preprophase band is not always used or needed and there appears to be an age or distance-dependent character to the information. Cells treated with the anti-actin drug, latrunculin B, are still able to position the preprophase nucleus suggesting that microtubules may play a dominant role in premitotic positioning. Furthermore, in treated cells, spindle location and phragmoplast insertion are frequently abnormal suggesting that actin plays a significant role in nuclear anchoring and phragmoplast guidance. Thus, the microtubule and actin components of the preprophase band/phragmosome execute complementary activities to ensure proper orientation of the division plane.

Bridged Bicyclo Compounds, Heterocyclic↗
PubMed1995

Predictors of dietary intake in a functionally dependent elderly population in the community.

OBJECTIVES: The aim of this study was to describe dietary intake and identify predictors of energy and protein intake in a group of high-risk elderly people. METHODS: All elderly persons receiving publicly financed home care services in the area of Sherbrooke, Quebec, Canada, were eligible. Subjects (n = 145) 60 to 94 years of age from three home care programs were interviewed to measure sociodemographic, health, and food-related behavior variables. Three nonconsecutive 24-hour recalls were used to describe usual dietary intake. Independent predictors of energy and protein intake were derived from multiple regression analyses. RESULTS: Very low mean energy intakes were observed in this functionally dependent population. More than 50% of the study subjects did not meet the recommended levels of daily protein intake (0.8 g/kg body weight). Significant independent determinants of intake were burden of disease, stress, poor appetite, and vision. CONCLUSIONS: Results suggest that community-living elderly people with loss of autonomy may have more nutritional problems than healthy elderly individuals. Surveillance of predictors of dietary intake may enable early detection and prevention of nutritional deficits.

Activities of Daily Living↗
PubMed1981

Contact sensitivity in the guinea pig eye.

Guinea pigs were sensitized systemically with the contact sensitizer oxazolone and challenged by topical application of the chemical to the eye and the skin. Inflammatory reactions of the conjunctiva, cornea and skin were uniformly elicited, but these were most intense clinically following intradermal sensitization with mycobacterial adjuvants. Mononuclear, neutrophilic and eosinophilic leukocytes infiltrated the ocular tissues and skin 24 hours after challenge. Basophils, which were prominent in the cutaneous reactions, were virtually absent from ocular tissues.

Adjuvants, Immunologic↗
PubMed1979

Ocular findings in systemic cutaneous basophil hypersensitivity.

SCBH was induced by immunizing guinea pigs with a protein antigen and challenging 1 week later with a large intraperitoneal dose of the same antigen. Animals developed a delayed-onset, erythematous skin rash and dermal infiltration by basophils and eosinophils. The uveal tracts of these animals were infiltrated by eosinophils, as were several other internal organs. The eye is affected in SCBH, and as in other forms of ocular cell-mediated hypersensitivity, the eosinophil is a prominent cellular component of these reactions.

Animals↗
PubMed1977

Angiography: an essential diagnostic aid in asymptomatic aortic aneurysm?

Aortography is a highly desirable diagnostic procedure for evaluating clinically diagnosed abdominal aortic aneurysm. In a retrospective study of 83 patients with such aneurysms, routine angiographic investigation changed the course of management in 17. The morbidity associated with angiography in the investigation of abdominal aortic aneurysm has been minimal. In this situation angiography provides more information than ultrasonography and therefore should be used routinely.

Aged↗
PubMed1975

Molecular order in Acholeplasma laidlawii membranes as determined by deuterium magnetic resonance of biosynthetically-incorporated specifically-labelled lipids.

The first application of deuterium magentic resonance of specifically labelled lipids to the study of a natural biological membrane is described. Palmitic acid labelled at the terminal methyl group with deuterium was incorporated biosynthetically into the lipids of the plasma membrane of Acholeplasma laidlawii. The deuterium nuclear magnetic resonance spectra contain quadrupole splittings which yield directly order parameters for this region of the membrane. Below the growth temperature (37 degrees C) the spectra are indicative of lipid in both gel and liquid crystalline states. Above this temperature they demonstrate the existence of an entirely liquid crystalline membrane whose order parameter decreases rapidly with increasing temperature. Comparison with egg phosphatidylcholine over the same temperature range shows a more rapid change in order with temperature for the A. laidlawii membranes.

Acholeplasma laidlawii↗
PubMedDate not supplied

[Intussusception. 188 treated patients during 22 years (author's transl)].

This is a review of 188 cases of intussusception collected in 4 separate studies over an 18 year period and compared with each other. An early diagnosis by the pediatrician, the immediate consultation of a pediatric surgeon to detect signs of peritoneal irritation and to attend the barium enema and a well trained pediatric radiologist are essential for success with the barium enema technic of reduction. The percentage of successful reduction by this method increased to 72% in 1972-1974 and then dropped to 56% during the following year. The main factor for this change was the implication of less experienced radiology residents.

Barium Sulfate↗
PubMedDate not supplied

[The impact of a food service in the school milieu on the quality of nutrition in children].

The food service at the Le Tremplin school (QC), which is managed by a non-profit organization including parents and members of the community, was evaluated in terms of its impact on the nutritional quality of the meals consumed by the students from the point of view of the prevention of cardiovascular diseases (CVDs) in children. This was done by comparing it with a traditional food service operated by a concessionnaire. On the nutritional level, the menus offered in the two schools were comparable: in both cases, they fell far short of meeting nutritional recommendations related to the prevention of CVDs. In other respects, the nutritional value of the meals consumed by the children differed according to the school. It was closer to meeting recommendations in the case of the Le Tremplin school. The results obtained show that the organization of the food service at the Le Tremplin school appears to favour a more adequate consumption of lipids and carbohydrates, as well as a more appropriate distribution of the different fatty acids in the food.

Cardiovascular Diseases↗