Biomedical subjects

D Lamoureux

Publications and source records attributed to D Lamoureux.

8 recordsLinked to original sources

PubMed2005

Construction and characterization of BAC libraries from major grapevine cultivars.

Genome projects were initiated on grapevine (Vitis vinifera L., 2n=38, genome size 475 Mb) through the successful construction of four bacterial artificial chromosome (BAC) libraries from three major cultivars, Cabernet Sauvignon (Cabernet S), Syrah and two different clones of Pinot Noir (Pinot N). Depending on the library, the genome coverage represented 4.5-14.8 genome equivalents with clones having a mean insert size of 93-158 kb. BAC pools suitable for PCR screening were constructed for two of these BAC libraries [Cabernet S and Pinot N clone (cl) 115] and subsequently used to confirm the genome coverage of both libraries by PCR anchoring of 74 genetic markers sampled from the 19 linkage groups. For ten of these markers, two bands on separate BAC pools were differentiated that could correspond either to different alleles or to a duplication of the locus being studied. Finally, a preliminary assessment of the correspondence between genetic and physical distances was made through the anchoring of all the markers mapped along linkage group 1 of the V. vinifera genetic map. A pair of markers, 2.1 cM apart, anchored the same BAC clones, which allowed us to estimate that 1 cM corresponded in this particular region to a maximum length of 130 kb.

Chromosome Mapping↗

PubMed2000

Standardization of a neuromotor test battery: the CATSYS system.

Interindividual and intraindividual variability in neuromotor behaviors is expected and normal. Early changes in neuromotor behaviors associated with neurodegenerative disorders or neurotoxic effects are often subtle and fluctuating in their characteristics. Therefore, their detection at an early stage is particularly difficult without precise recording instruments. The CATSYS system developed by Danish Product Development (DPD) is a portable device recording four measures of neuromotor control including tremor, reaction time, hand coordination and postural sway. The aim of this study is to develop a set of normative data. One hundred and fifty healthy men and women were divided into five age groups: (1) 20 to 29 years (n=30); (2) 30 to 39 years (n=30); (3) 40 to 49 years (n=30); (4) 50 to 59 years (n=30); (5) 60 to 70 years (n=30). All participants were free of neurological deficits at the time of testing and they were tested individually for approximately 30 min. Hand coordination was measured with prono-supination and finger-tapping movements executed at constant and accelerated rhythms. Reaction time was assessed in both hands using a hand held switch activated by the thumb. Postural tremor was quantified in both hands during 24.6 sec. by asking the subject to hold a stylus horizontally at 10 cm in front of his/her navel. The stylus contained a biaxial accelerometer. Postural sway was tested by asking the subject to stand on a force platform for 75 sec. under four conditions: (1) eyes open; (2) eyes closed; (3) eyes open standing on a foam pad; and (4) eyes closed standing on a foam pad. ANOVAs and multiple comparison tests were performed and the results were examined taking into account age, gender and experimental condition effects.

Adult↗

PubMed1996

The effect of gabapentin on brain gamma-aminobutyric acid in patients with epilepsy.

Gabapentin has come into clinical use as adjunctive therapy in the treatment of epilepsy. Designed to mimic gamma-aminobutyric acid (GABA), its mechanism of action remains elusive. In vivo measurements of GABA in human brain were made using 1H magnetic resonance spectroscopy. We used a 2.1-T magnetic resonance imager-spectrometer and an 8-cm surface coil to measure a 13.5-cm3 volume in the occipital cortex. GABA levels were measured in 14 patients enrolled in an open-lbel trial of gabapentin. GABA was elevated in patients taking gabapentin compared with 14 complex partial epilepsy patients, matched for antiepileptic drug treatment. Brain GABA levels appeared to be higher in patients taking high-dose gabapentin (3,300-3,600 mg/day) than in those taking standard doses (1,200-2,400 mg/day). Gabapentin appears to increase human brain GABA levels.

Acetates↗

PubMed1995

Epilepsy surgery in adults.

Epilepsy surgery is capable of stopping seizures or markedly reducing their frequency in selected patients with medically refractory epilepsy. Presurgical evaluation, as currently practiced, requires concordance among a battery of localizing tests. Cost-effectiveness is increasingly important in the development of optimal presurgical protocols and surgical procedures in specific patient populations.

Adult↗

PubMed1983

Changes in cardiac transcapillary exchange with metabolic coronary vasodilation in the intact dog.

The effects of metabolic coronary vasodilation on transcapillary exchange in the heart were examined in anesthetized dogs by use of the multiple indicator dilution technique. Animals were studied under basal conditions and during coronary sinus pacing. To obviate adrenal medullary stimulation, catheters were placed in coronary artery and coronary sinus in a closed chest preparation. Plasma catecholamine concentrations were determined to provide an index of the level of sympathetic tone. Labeled albumin and sucrose were injected into the coronary artery, and outflow dilution curves were secured. Analysis of these, with a model incorporating throughput and returning components, and heterogeneity of capillary transit times, provided parameters reflecting flow, permeability-surface product for sucrose, and capillary heterogeneity. Coronary sinus pacing increased both heart rate and plasma norepinephrine values; in response, myocardial oxygen consumption increased, metabolic vasodilation occurred, and coronary flow increased. The capillary permeability-surface product for sucrose increased with the flow but tended to plateau at higher values, showing a saturation phenomenon. Capillary heterogeneity, present in control animals with low sympathetic tone, was grossly decreased during cardiac metabolic activation. The Crone-Renkin approximation formula for the permeability-surface product yielded values that were too low at low flows and values approaching those from the complete model at high flows. The findings indicate an integrated pattern of circulatory response to cardiac metabolic activation characterized by decreased resistance, increased flow, increased permeability-surface product, and reduced heterogeneity. The last two effects amplify the capacity of increased flow to deliver substrates to heart muscle cells.

Animals↗

PubMed1983

[Not Available].

Explore the source record for details and available documents.

Canada↗

PubMedDate not supplied

Cell junctions in lymphomas: study of a primary ovarian T-cell lymphoma and review of fifty-six other cases of lymphoma.

A case of primary ovarian lymphoma was studied by light microscopy, immunohistochemistry, and electron microscopy. The ultrastructural study revealed the presence of cell junctions of the paired subplasmalemmal densities and tight junctions between adjacent lymphoid cells. Fifty-six cases of non-Hodgkin's lymphoma randomly selected from the files of the Electron Microscopy Facility of the Faculty of Health Sciences, McMaster University, were reviewed. Paired subplasmalemmal densities and tight junctions were identified in five of the cases (9%). This study suggests that the absence of cell junctions should not be considered an essential criterion for the ultrastructural diagnosis of lymphomas.

Cytoplasm↗

PubMedDate not supplied

Neuromotor profiles: what are they and what can we learn from them?

Eye movements, alternating movements, rapid pointing movements, and various tremors were measured on patients with Parkinson's disease (n = 21), on Cree subjects exposed to methylmercury (n = 36), and on healthy control subjects (n = 30). Neuromotor profiles were created according to thirty characteristics extracted from test results of four subgroups matched for age and composed of six subjects each. Z scores were calculated with respect to the mean and standard deviation of the control group for each of the 30 characteristics. The subgroup with the lower methylmercury blood level had larger z scores than the control subgroup and with a few positive values above one standard deviation. The subgroup with the higher methylmercury blood level had several z scores above two standard deviations. Interestingly, the abnormal values for the subgroup with Parkinson's disease were mostly limited to static tremor recorded with no visual feedback and reached up to 5 standard deviations. These results indicate that neuromotor profiles can be used to summarize information extracted from different neuromotor tests and to differentiate neurological conditions.

Eye Movements↗