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P Frémont

Publications and source records attributed to P Frémont.

14 recordsLinked to original sources
PubMed2001

[Evaluation of medical web sites. Interobserver and intraobserver reliability of an evaluation tool].

OBJECTIVE: To develop and test the reliability of a tool for rating websites that provide information on evidence-based medicine. DESIGN: For each site, 60% of the score was given for content (eight criteria) and 40% was given for organization and presentation (nine criteria). Five of 10 randomly selected sites met the inclusion criteria and were used by three observers to test the accuracy of the tool. Each site was rated twice by each observer, with a 3-week interval between ratings. SETTING: Laval University, Quebec city. PARTICIPANTS: Three observers. MAIN OUTCOME MEASURES: The intraclass correlation coefficient (ICC) was used to rate the reliability of the tool. RESULTS: Average overall scores for the five sites were 40%, 79%, 83%, 88%, and 89%. All three observers rated the same two sites in fourth and fifth place and gave the top three ratings to the other three sites. The overall rating of the five sites by the three observers yielded an ICC of 0.93 to 0.97. An ICC of 0.87 was obtained for the two overall ratings conducted 3 weeks apart. CONCLUSION: This new tool offers excellent intraobserver and interobserver measurement reliability and is an excellent means of distinguishing between medical websites of varying quality. For best results, we recommend that the tool be used simultaneously by two observers and that differences be resolved by consensus.

Evaluation Studies as Topic↗
PubMed1999

[Drug use in the elderly. Use of psychotropic drugs in the elderly: overuse or underuse?].

POORLY DEFINED USE: The first of three leading problems in the use of psychotropic drugs in elderly subjects is related to the overall situation of their use, often tainted by an ìideologicalî point of view. Prescribers are ìforî or ìagainstî psychotropic and justify their prescription by the need to take into account the general situation rather than strictly clinical arguments. Some prescriptions are written for the family or institutions. Even the definition of the elderly subject is extremely vague and is generally taken to include subjects over 65, a very heterogeneous group. Too few studies have been devoted to subjects over 80. NEED FOR GOOD CLINICAL ANALYSIS: The second type of problem is raised by the clinical expression of psychotic disorders in the elderly, too often considered to be limited to the classical signs of depression, dementia, and confusion. A careful clinical analysis is essential before prescription, with an adapted therapeutic response to each pathological situation. In addition, good clinical analysis would allow better diagnosis of depression, a condition largely underestimated and undertreated. BY THERAPEUTIC CLASS: It is now classical to denounce inappropriate use of neuroleptics and question their efficacy in controlling behavioral disorders in dementia. This attitude results from the impact of the adverse effects. Several authors have emphasized the contribution of new antipsychotic drugs but very few controlled studies have been reported. For antidepressors, the current consensus would suggest that prescription doses are generally insufficient and treatment durations too short. Finally, though it is widely accepted that use of benzodiazepines should be limited in dose and duration, data on drug use however show the contrary, emphasizing the difficulty in changing habits. New compounds including thymoregulators are increasingly used for elderly subjects but here again, like for antipsychotic drugs, too few studies have been published and many points remain to be elucidated.

Aged↗
PubMed1998

Faculty evaluation in departments of family medicine: do our universities measure up?

Family medicine programmes at Canadian universities have expanded dramatically over the past several years. The development of effective means of faculty evaluation is a real concern for these departments as they strive to maintain the high quality of their teaching programmes in the face of rapid change. The literature on faculty evaluation, including reviews and articles discussing the application of faculty evaluations, is reviewed. The current state of faculty evaluation at three Canadian family medicine department has also been surveyed. Student evaluations were found to be valid, accurate and well studied. They are not perfect, however, and require the use of additional methods such as peer review or video review in conjunction in order to provide a comprehensive evaluation of all areas of faculty activity. Faculty evaluation in family medicine teaching units and community-based settings has not been well studied. Our survey of faculty evaluation at three Canadian universities shows much room for improvement, particularly in community-based settings where evaluation is almost non-existent. Expanding the use of faculty evaluations for formative means and linking evaluation to faculty development opportunities are essential if improvements to the currently used systems are to be successful and accepted by faculty. Special consideration must be given to community-based settings where systems designed for use in larger university settings will need to be modified substantially before they can be used effectively. Further research is required in this area.

Canada↗
PubMed1991

Fatigue and recovery of rat soleus muscle are influenced by inhibition of an intracellular carbonic anhydrase isoform.

Carbonic anhydrase III (CA III; EC 4.2.1.1) is the most abundant cytosolic enzyme in type I skeletal muscle fibers. Methazolamide, a specific CA inhibitor, was used to characterize the effects of inhibiting CA III on the resistance to fatigue and recovery of the rat soleus muscle using a 60-min fatigue protocol performed in vitro at 25 degrees C. Incubation with 10(-3) M methazolamide resulted in a smaller decrease in tension production during the fatigue protocol, thereby increasing the total tension-time integral for the fatigue test. However, the rate and extent of recovery after the test were lower in the experimental group compared with the control group. A similar effect was observed at physiological temperature (35 degrees C). The results indicate that inhibition of CA III significantly influences tension production as early as 30 s into the stimulation protocol. Inhibition of CA III only during the recovery period did not influence the recovery profile, thereby indicating that the impaired recovery was related to the presence of methazolamide during the stimulation period.

Acetazolamide↗
PubMed1989

Acetazolamide-sensitive and resistant carbonic anhydrase activity in rat and rabbit skeletal muscles of different fiber type composition.

1. Acetazolamide (ACET)-resistant and -sensitive carbonic anhydrase (CA) activity was measured in post-mitochondrial supernatants from the soleus (SOL), deep vastus lateralis (DVL) and superficial vastus lateralis (SVL) muscles of rats and rabbits. 2. The relative total CA activity in the three muscles of both species can be summarized as SOL greater than DVL greater than SVL. 3. ACET-resistant CA activity was found in the SOL and DVL muscles of both species whereas a low level of ACET-sensitive CA activity was detected in the SVL muscle. 4. ACET-sensitive CA activity was also found in sarcoplasmic reticulum preparations from rat and rabbit SOL muscles.

Acetazolamide↗
PubMed1989

Inhibition of carbonic anhydrases in type I muscle fibers influences contractility.

We tested the effects of inhibiting the carbonic anhydrase activity of rat soleus and extensor digitorum longus muscles on the isometric contractile properties and the resistance to fatigue. SOL and EDL muscles from female rats were incubated in vitro in the presence of methazolamide, a specific inhibitor of carbonic anhydrase, before determining their contractile properties. Methazolamide had no effects on the contractile properties of the soleus muscle (10(-5) or 10(-3) M) and extensor digitorum longus (10(-3) M), except for the half-relaxation time of the soleus muscle which increased significantly. Values for half-relaxation time were significantly increased with both concentrations of the inhibitor. Muscles were then submitted to a fatigue protocol lasting 30 min. During the fatigue test, no significant difference was observed between control and 10(-5) M methazolamide soleus muscles. In presence of 10(-3) M methazolamide however, the soleus muscle showed a significantly increased resistance to fatigue compared with control preparations. No significant effect was observed with the extensor digitorum longus muscle exposed to 10(-3) M methazolamide. Results are discussed in terms of the presence of two different isoforms of carbonic anhydrase that may be associated with calcium uptake and energy metabolic processes, respectively.

Animals↗
PubMed1988

Carbonic anhydrase III in skeletal muscle fibers: an immunocytochemical and biochemical study.

The objectives of the present study were to determine if carbonic anhydrase III (CA III) demonstrated a specific association for any particular organelle or structure of the skeletal muscle cell and to quantify the activity and content of this enzyme in different types of skeletal muscle fibers. Ultrastructural localization of CA III in the soleus (SOL), deep vastus lateralis (DVL), and superficial vastus lateralis (SVL), composed of predominantly type I, IIa, and IIb fibers, respectively, was performed using a high-resolution immunocytochemical technique and antibody specific for CA III on ultra-thin sections of skeletal muscle embedded in the water-soluble medium polyvinyl alcohol (PVA). The results indicated a uniform distribution of CA III within the sarcomere. Mitochondria, nuclei, triads, Z-, and M-bands were not specifically labeled. Immunoblotting of washed myofibril preparations did not show any detectable CA III associated with this structure. In addition to quantification of the immunogold labeling, CA III activity and content were assayed in the post-mitochondrial supernatant of the three muscles. In the SOL, these values were found to be 3.6-7.6 times higher than in the DVL. The SVL showed a labeling intensity slightly higher than background level, while the enzyme activity and content were indistinguishable from background levels. We therefore conclude that CA III is randomly distributed in the cytoplasm of the three muscle fiber types and that the relative CA III content and activity in the three muscles studied is SOL greater than DVL greater than SVL approximately equal to 0.

Animals↗
PubMed1987

Regulation of carbonic anhydrase III by thyroid hormone: opposite modulation in slow- and fast-twitch skeletal muscle.

This laboratory previously reported that a major 30 kilodalton (kDa) protein of the soluble cytoplasmic fraction of the rat slow-twitch soleus muscle is modulated by thyroid hormone. This protein has been purified and a portion of the primary structure has been determined. The sequence analysis suggested that the 30-kDa protein is carbonic anhydrase III (CA III; EC 4.2.1.1). The reaction of the protein with a CA III specific antibody and the similar modulation of CA III by thyroid hormone also support this conclusion. Immunochemical quantification of CA III and measurement of CA activity were performed in skeletal muscles of defined fiber-type composition from rats that were rendered hyperthyroid by treatment with 3,3',5-triiodo-L-thyronine. These experiments revealed that CA activity and CA III content are deinduced in the soleus muscle (primarily type I fibers) and induced in the superficial vastus lateralis muscle (primarily type IIb), whereas no changes were detected in the tibialis anterior muscle (primary type IIa). These results show that the modulation of CA III by thyroid hormone in rat skeletal muscle is not limited to the slow-twitch soleus muscle and that the amplitude and direction of this modulation are directly related to the initial fiber-type composition of the skeletal muscle.

Amino Acid Sequence↗
PubMed1986

Recovery of biologically functional messenger RNA from agarose gels by passive elution.

A general method for isolating biologically active messenger RNA (mRNA) from agarose gels is reported. Purified cellular RNA is resolved by preparative agarose gel electrophoresis and recovered in high yields (80%) by passive diffusion. Polyadenylated mRNA isolated from the eluted RNA is functionally intact based on the ability of the RNA to serve as a template in cell-free translation systems and complementary DNA synthesis reactions. The entire procedure is simple and rapid. A substantial purification of the mRNAs coding for skeletal muscle myosin heavy chain, light chain subunits and carbonic anhydrase III has been achieved employing this method.

Animals↗
PubMedDate not supplied

Differential modulation of carbonic anhydrase (CA III) in slow- and fast-twitch skeletal muscles of rat following denervation and reinnervation.

Carbonic anhydrase III (CA III) is influenced by neuronal factors in skeletal muscles of the rat. CA III protein and its mRNA levels were assessed in slow- and fast-twitch muscles after short-term denervation by ligature of the sciatic nerve and reinnervation following removal of the sheath tightly fixed around the nerve. Significant elevations in the CA III mRNA content of fast-twitch muscles were recorded after denervation, but they were cancelled following spontaneous muscle reinnervation. No such variations were observed in the slow-twitch soleus muscle. CA III specific activity or cytosolic CA III protein content increased in both types of muscles after denervation, while a decrease was solely observed in the soleus after reinnervation. These results suggest that neuronal mediators may be responsible for up and down variations in CA III gene expression and (or) mRNA stability in slow- and fast-twitch muscles exposed to identical stimuli. Variations of the mRNA and the protein probably reflect, in a time-related manner, the well-programmed changes in fiber type of the muscles in the context of the denervation-reinnervation model.

Animals↗
PubMedDate not supplied

Carbonic anhydrase in mouse skeletal muscle and its influence on contractility.

Carbonic anhydrase III (EC 4.2.1.1) is the most abundant cytosolic protein in type I skeletal muscle fibers. Investigations of its physiological role have mostly been conducted with rat muscles, which sometimes are unsuitable for in vitro studies. The objective of the present study was to characterize the carbonic anhydrase in the mouse soleus muscle to verify if this muscle can be used as a model to further study the enzyme's function. Total carbonic anhydrase specific activity in the mouse soleus was comparable to the value for rat. However, 60% of the total carbonic anhydrase activity in the mouse was of the sulfonamide-sensitive type and, therefore, not related to carbonic anhydrase III. Electrophoretic analysis revealed the presence of a 29-kDa protein in total and cytosolic extracts of the mouse soleus. Immunoblotting with an antibody developed against rat carbonic anhydrase III showed that it was also specific for this 29-kDa peptide, which presumably is the mouse carbonic anhydrase III. Inhibition of the sulfonamide-sensitive activity had no effect on contractile and fatigue characteristics, whereas inhibition of the sulfonamide-resistant carbonic anhydrase III activity led to a significant increase in resistance to fatigue. We conclude that the mouse soleus may represent an excellent model to understand the contribution of different carbonic anhydrase isoforms to muscle physiology.

Animals↗
PubMedDate not supplied

Effect of carbonic anhydrase III inhibition on substrate utilization and fatigue in rat soleus.

Carbonic anhydrase III (CA III; EC 4.2.1.1) is the most abundant cytosolic enzyme in type I skeletal muscle fibers. We have previously shown that inhibiting the CA III activity of type I muscle can influence fatigability. Our goal was to test the hypothesis that the influence on fatigability of CA III inhibition is linked to an increased utilization of carbohydrates. Rat soleus muscles were incubated in vitro in a physiological solution with or without CA inhibitor (methazolamide, 1 mM) and submitted to a fatigue protocol. When the bathing solution contained glucose, the muscles incubated with methazolamide maintained a higher level of tension production than control muscles for the first 55-60 min of the test compared with 35-40 min when glucose was not added. Measurement of muscle glycogen content revealed that muscles incubated with CA inhibitor were utilizing their glycogen at a higher rate than control muscles over the first 45 min of the fatigue protocol. When glycolysis was inhibited with sodium iodoacetate, fatigability was not influenced by the addition of a CA inhibitor. These results further support the existence of a link between CA III activity and energy metabolism in type I skeletal muscle fibers.

Animals↗
PubMedDate not supplied

[Continuing education].

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Education, Continuing↗