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Biomedical subjects

F Girard

Publications and source records attributed to F Girard.

At least 235 records · Page 13Linked to original sources
PubMedDate not supplied

Localized T1 measurements using an inversion-recovery OSIRIS method.

This work presents a new method for localized T1 measurements, based upon the OSIRIS scheme. It relies on the use of a non-selective 180 degrees pulse applied before the OSIRIS preparation cycle. The accuracy of the method has been verified with test tubes and in vivo for two nuclei, 1H and 19F. The accuracy of the T1 values is discussed, as well as possible applications of the inversion-recovery method to non-invasive in vivo pO2 measurements.

Animals↗
PubMedDate not supplied

Microsequencing evidence for the maturation of human proopiomelanocortin into an 18 amino acid beta-melanocyte stimulating hormone [h beta MSH(5-22)] in nonpituitary tissue.

Sixty pmoles of a material with molecular size, immunological, and RP-HPLC characteristics identical to that of h beta MSH(5-22) were purified from a bronchial carcinoid tumor responsible for the ectopic ACTH syndrome. The first 16 cycles of microsequencing revealed the following sequence: Asp-Glu-Gly-Pro-Tyr-Arg-Met-Glu-X-Phe-Arg-Trp-Gly-X-Pro- Pro-, identical to the first 16 amino acids of h beta MSH(5-22). Since this material was recognized by an antibody which requires the free COOH-terminal Asp22 residue, it can be assumed that it is indeed h beta MSH(5-22). We also show that neither the 5 N acetic acid nor the 1 N HCl extraction procedure artefactually generated h beta MSH-like material in normal or tumoral human pituitaries and in nonpituitary tumors. We conclude that h beta MSH(5-22) is a normal maturation product of proopiomelanocortin in the human nonpituitary tissues which express its gene, including the hypothalamus and ACTH-secreting tumors.

Amino Acid Sequence↗
PubMedDate not supplied

Expression and subcellular localization of dystrophin in skeletal, cardiac and smooth muscles during the human development.

Dystrophin, the product of the DMD gene, is present in all muscle types in normal individuals. Its function has yet to be elucidated, but its absence or the presence of a truncated version of the protein is responsible for the appearance of Duchenne and Becker muscular dystrophies. Using monoclonal antibodies raised against distinct regions of the dystrophin protein, we have examined its expression and subcellular distribution during the human development in skeletal and smooth muscles. We show that both dystrophin expression and its association to the plasma membrane take place earlier in cardiac and smooth muscles (8 weeks of gestation) than in skeletal muscle. In skeletal muscle, dystrophin is first detected in the cytoplasm, and progressively localizes to the plasma membrane from 10 weeks onwards. Since we have obtained marked differences in staining when using antibodies against either a central region of the protein or the C-terminal part, we suggest that different fetal and adult dystrophin isoforms are expressed, probably differing in their C-terminal domain. These findings are discussed in the context of the pathology of Duchenne muscular dystrophy.

Adult↗
PubMedDate not supplied

Infraclavicular block with lateral approach and nerve stimulation: extent of anesthesia and adverse effects.

BACKGROUND AND OBJECTIVES: The infraclavicular approach to the brachial plexus is little used despite theoretical advantages of the technique. Using a vertical paracoracoid approach, we assessed the extent of the sensory block and the incidence of adverse effects. METHODS: After obtaining informed consent, 100 patients undergoing surgical procedures distal to the elbow were evaluated. The block was performed using a peripheral nerve stimulator. The puncture site was located in the infraclavicular fossa; the direction of the insulated needle was perpendicular to the skin. Motor response was sought in the hand or wrist at < or = 0.6 mA. A total of 40 mL of 1.5% mepivacaine was administered as a single injection. The sensory block was evaluated every 5 minutes for 30 minutes before surgery in the cutaneous distribution of terminal branches of the brachial plexus. RESULTS: When one considers the cutaneous distributions of the median, ulnar, radial, and musculocutaneous nerves, the success rate was 89% for surgery without need for additional peripheral nerve blocks or general anesthesia. In contrast, cutaneous areas innervated by the axillary and medial cutaneous nerves were rarely anesthetized. We were unable to demonstrate a correlation between the intensity of the stimulation and the success of the block. On the other hand, a correlation was found between tourniquet sensation and the absence of anesthesia of the medial cutaneous nerve of the arm. Local anesthetic toxicity, Horner's syndrome, and vascular puncture were respectively observed in 1%, 4%, and 5% of cases. The depth of the needle introduction was correlated with the body mass index (P <.001; r =.63). CONCLUSION: Single injection infraclavicular block, using a vertical paracoracoid approach, appears suitable for surgery distal to the elbow. Selective anesthesia of the medial cutaneous nerve is useful in improving tolerance of the tourniquet.

Anesthetics, Local↗
PubMedDate not supplied

Synthesis of 5'-thioalkyl, sulfoxide and sulfone pyrimidine nucleosides.

The preparation of 5'-thioalkyl, sulfoxide and sulfone pyrimidine nucleosides is [4-11] is described. The key steps of this synthesis are the nucleophilic displacements of a chlorine by a thioalkyl sodium salt or the direct introduction of the thioalkyl group under Mitsunobu conditions.

Animals↗
PubMedDate not supplied

[Clinical research, evaluation of care and quality assurance].

This paper aims to clarify the concepts and terminology of clinical research, evaluation, and quality. Clinical research or clinical epidemiology aims to demonstrate the efficacy of medical care. The optimal methodology is a randomized, double-blind trial that allows a causal inference in respect of efficacy. This should be the first stage before generalization of all medical practice. Evaluation of quality of care aims to verify the effectiveness of medical care by comparing practice with references. The optimal methodology is clinical audit that allows fine-tuned diagnosis of the existence of deviant practices. The analysis of causes and correction of the care process are an integral part of the evaluation work. Thus quality assurance and quality management concepts and methods have been developed which tend to ensure solutions for better care and to maintain the level of quality of care to achieve patient satisfaction. Evaluation, clinical research and management quality could in fact be seen as the complementary facets of a comprehensive approach to quality of care.

Clinical Protocols↗
PubMedDate not supplied

[Rheology of bronchial secretions and mucociliary transport (author's transl)].

Optimal relationships between mucociliary clearance and rheological properties of bronchial secretions expectorated by patients with chronic bronchitis have been analysed by successive measurements of visco-elasticity with a rotational rheometer and of transport velocity on frog palate mucosa. It appears that the role of the elastic component is predominent. Sputum characterized by very low strain recovery (SR less than 4 units) or conversely by very high elasticity (SR greater than 20 units) is transported at a low rate in comparison to that of the control frog mucus (relative transport rate less than 0.5). Pronounced hyperviscosity of sputum (no greater than 200 poises) appears also as a limiting factor to the mucociliary transport. The best transported secretions (relative transport rate greater than 0.7) are characterized by a relative elasticity (SR) of 4 to 13 units and a viscosity (no) of 25 to 200 poises. Under the action of mucolytic agents such as N-acetylcysteine, sputum initially characterized by low strain recovery (SR less than 4 units) is transported at a much slower rate which is related to the increased loss of elasticity. These results indicate that mucolytic drugs must be administered with great care in patients with chronic bronchitis. Moreover, they should not be used in patients with very low visco-elastic secretions which reflect the non-functional state of the bronchial mucosa.

Acetylcysteine↗
PubMedDate not supplied

[Cost of medical imaging practices in acute abdominal syndromes].

OBJECTIVES: To describe the costs of medical imaging practices in the diagnosis management of acute abdominal pain (AAP). METHODS: Medical imaging techniques until decision for treatment were prospectively recorded in patients presenting with AAP. Direct costs used hospital analytic accountability. Time of human resources involved was also surveyed prospectively. RESULTS: In 122 adult patients (2.3 examinations on average) before treatment decision making, the more frequent practices were: initial plain abdomen x-ray followed by tomodensitometry (36.8%), by echography or endoscopy (17.2%), plain abdomen solely (19.6%) or initial abdominal tomodensitometry (12.3%). Direct costs ranged from 977 to 1073 FF for practices with initial plain abdomen x-ray, and from 996 to 1150 FF with initial tomodensitometry. It ranged from 808 to 880 FF when the treatment decision was surgery, and 300 FF higher when it was medical. CONCLUSION: Differences in costs assessed for practices were very narrow. Such information should be taken into account to determine cost-effective strategies, and to built up reference guidelines.

Abdomen, Acute↗