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Biomedical subjects

A Morin

Publications and source records attributed to A Morin.

At least 19 recordsLinked to original sources

The genotype 3-specific hepatitis C virus core protein residue phenylalanine 164 increases steatosis in an in vitro cellular model.

BACKGROUND AND AIMS: The prevalence and severity of liver steatosis are higher in patients infected with genotype 3 hepatitis C virus (HCV) than in patients infected with other genotypes. HCV core protein is known to affect lipid metabolism, inducing lipid droplet accumulation both in vitro and in vivo. An in vitro cellular model was used to investigate whether an HCV core protein with residues specific to genotype 3 increased this phenomenon. METHODS: Sequence comparisons for HCV core protein domain II, which is known to interact with lipid droplets, identified the phenylalanine (F) residue at position 164 as the only residue specific to genotype 3. The area covered by lipid droplets in sections of cells producing a wild-type genotype 1a HCV core protein was compared with that in cells producing a Y164F mutant protein. RESULTS: Cumulative lipid droplet area was significantly greater in sections of cells producing the Y164F mutant HCV core protein than in cells producing the wild-type protein (p<0.001). The frequency of cell sections containing more than 3 mum(2) of lipid droplets, in particular, was higher for the mutant than for the wild-type protein. CONCLUSION: The data provide a molecular explanation for HCV genotype 3-specific lipid accumulation. This difference between genotypes may be due to phenylalanine having a higher affinity for lipids than tyrosine (Y). These observations provide useful information for further studies of the mechanisms involved in HCV-induced steatosis.

Animals↗

Childhood leukaemia incidence around French nuclear installations using geographic zoning based on gaseous discharge dose estimates.

The present study investigated for the first time the incidence of childhood leukaemia (1990-2001) around French nuclear installations using a geographic zoning based on estimated doses to the red bone marrow due to gaseous radioactive discharges. The observed number of cases of acute leukaemia (O=750) in 40 km2 centred on 23 French nuclear installations between 1990 and 2001 was lower than expected (E=795.01), although not significantly so (standardised incidence ratio SIR=0.94, 95% confidence interval=(0.88-1.01)). In none of the five zones defined on the basis of the estimated doses was the SIR significantly >1. There was no evidence of a trend in SIR with the estimated doses for all the children or for any of the three age groups studied. This study confirmed that there was no evidence of an increased incidence of childhood leukaemia around the 23 French nuclear sites.

Acute Disease↗

Functional morphology of phonation evaluated by dynamic MRI.

The complex anatomy of the larynx is a consequence of its various airway functions. The aim of the present study was to evaluate which anatomical structures of the larynx soft tissues could be defined using MRI, and to investigate the feasibility of using this technique to assess the dynamic functions of the larynx. MRI images of the larynx of six healthy volunteers during speech production were obtained in vivo. The volunteers were asked to breathe out long and deep in order to prolong in a normal voice the emission of the vowels [i] (as in key) and [a] (as in car) and the consonant [ch] (as in ship). We demonstrated the modification of the larynx position, which is high for [i] and low for [a], and the modification of the vocal folds which is adducted and abducted in [i] and kept abducted in [ch]. Dynamic MRI allows the possibility of multiplanar high-resolution imaging. It can provide information about the anatomy of the larynx and, it also has the ability to image moving laryngeal structures and to analyze vocal fold vibrations during phonation.

Adult↗

French population exposure to radon, terrestrial gamma and cosmic rays.

In France, natural sources account for most of the population exposure to ionising radiation. This exposure varies widely with area. Radon and gamma-ray exposure data come from national measurement campaigns; cosmic doses were calculated from city altitude. These data were corrected for season of measurement, housing characteristics and population density to study their relationship with health indicators. The crude average of indoor radon concentrations was 89 Bq m(-3), and the average corrected for season and housing characteristics was 83 Bq m(-3) (range over districts: 19-297). Weighting by district population density yielded a national average of 63 Bq m(-3). Gamma-ray dose rates averaged 55 nSv h(-1) (23-96) indoors and 46 nSv h(-1) (25-85) outdoors; corrections did not change the means. Corrected cosmic annual doses averaged 0.28 mSv (0.27-0.38). These corrections estimated the radiation exposure of the French population more accurately and represented its distribution well, thereby allowing its study as a cofactor in ecological studies.

Cosmic Radiation↗

RhoGDI-3, a promising system to investigate the regulatory function of rhoGDIs: uncoupling of inhibitory and shuttling functions of rhoGDIs.

rhoGDIs (Rho GDP dissociation inhibitors) are postulated to regulate the activity and the localization of small G-proteins of the Rho family by a shuttling process involving extraction of Rho from donor membranes, formation of inhibitory cytosolic rhoGDI/Rho complexes, and delivery of Rho to target membranes. However, the role of rhoGDIs in site-specific membrane targeting or extraction of Rho is still poorly understood. We investigated here the in vivo functions of two mammalian rhoGDIs: the specific rhoGDI-3 and the well-studied rhoGDI-1 (rhoGDI) after structure-based mutagenesis. We identified two sites in rhoGDIs, forming conserved interactions with their Rho target, whose mutation results in the uncoupling of inhibitory and shuttling functions of rhoGDIs in vivo. Remarkably, these rhoGDI mutants were detected at Rho-induced membrane ruffles or protrusions, where they co-localized with RhoG or Cdc42, probably identifying for the first time the site of extraction of a Rho protein by a rhoGDI in vivo. We propose that these mutations act by modifying the steady-state kinetics of the shuttling process regulated by rhoGDIs, such that transient steps at the cell membranes now become detectable. They should provide valuable tools for future investigations of the dynamics of membrane extraction or delivery of Rho proteins and their regulation by cellular partners.

Guanine Nucleotide Dissociation Inhibitors↗

The French language virtual medical university.

The work program of the French Language Virtual Medical University started about 2 years ago, and entered into a real active phase of development and implementation in 2002. Various national programs and organizational initiatives should accelerate and facilitate further appropriation of modem pedagogical approaches by knowledge providers and all users of the FSVMU, so as to advance on the way of virtual education. The French Language Virtual Medical University under the auspices of both the National Conference of Deans of Medical Schools and the International Conference of Deans of French-Speaking Medical Schools has been developed to create a major Internet portal for French-speaking distance medical learning and teaching. This construct should be representative of all medical schools in France and French-speaking countries. Contents will also be translated into English, Spanish and Arabic. All medical disciplines with their various levels of teaching are to be included. Cross-related fields are also going to be present in order to offer full range programs. The latter are intended to provide both initial and continuing education for medical students as well as all other categories of health professionals and medical and scientific research workers. To develop the appropriate technology and make such a portal, on one hand correspond to the specific educational requirements and proper training for health professionals, and on the other hand provide a general access to e-learning in all schools of medicine; in keeping with such goals, the following approaches should be stressed upon. To build a virtual space where individual patients, their families, patient associations as well as the general public, can obtain medical information of good quality for the purposes of both education and prevention. Providing such categories with reliable and validated sources of information, and offering an ethical basis for the increasing practice of e-medicine, represent in today's and tomorrow's world one of the great modern challenges for the medical community. Beyond the sole medical domain, the model offered by the FSVMU should be useful for the French-speaking Universities in all the fields of knowledge and training which are candidate to benefit from new educational means and methods.

Computer Simulation↗

Duplex Doppler ultrasound assessment of clitoral hemodynamics after topical administration of alprostadil in women with arousal and orgasmic disorders.

There are limited hemodynamic data in women with arousal or orgasmic disorders and even fewer normative control hemodynamic data in women without sexual dysfunction. In addition, there is limited experience with topical vasoactive agents (used to maximize genital smooth muscle relaxation) applied to the external genitalia during hemodynamic evaluations. The aim of this study was to report duplex Doppler ultrasound clitoral cavernosal arterial changes before and after topical PGE-1 (Alprostadil) administration in control women and in patients with arousal and orgasmic sexual disorders. We found that women with sexual arousal and orgasmic disorders had significantly (p < 0.05) diminished clitoral peak systolic and end diastolic velocity responses compared to controls. Further research is needed to establish the diagnostic role of topical vasoactive agents in the hemodynamic evaluation of women with sexual dysfunction.

Administration, Topical↗

[The maxillary sinus: evolution and function in aging].

The maxillary sinus, or Highmore's antrum, is located in the maxillary bone. The maxillary, above the buccal cavity, below the orbital cavity and outside the nasal fossa, is going to take a part in the formation of the three cavities which surround it. Although voluminous, it is consists of a light bone. This distinctive feature is essentially due to the fact that the maxillary has a cavity. The maxillary sinus occupies the upper 2/3s of this maxillary bone. It is the largest of the facial structure's cavities. Its volume is very variable, depending on the individual, the condition of their edentulousness and their age. We find small, average or large sinuses. This sinus communicates with the corresponding nasal fossa by a canal. It opens at the level of the nasofrontalis duct by a meatic ostium, an ostium located at the top of the meatus nasi medius, i.e. under the floor of the sinus. This highly positioned drainage location easily explains the problems that sinus pathologies can come up against. The sinus is lined with a mucous membrane and we can point out that in the normal condition this mucous membrane adheres weakly to the bone. It is more or less thick as a function of the pathologies to which the sinus has been subjected, or even as a function of the geographical location where the individual lives. The imaging of this sinus as a function of age is not obvious due to the fact that it is invisible throughout embryonic and foetal development, and that it only becomes visible to X-rays relatively late, at about 6 years old. Its role is important at the level of the growth of the facial structure because it is always easier to have growth around cavities. It also has a mechanical role concerning the transmission of shockwaves during traumas. In old individuals, due to the condition of the edentulousness, the volume of the sinus is larger; in fact one can note the resorption of the alveolar bone. The maxillary sinus is a cavity which plays a very important role throughout an individual's existence because of the previously mentioned reasons, and which could be used during surgical reconstructions, by the partial filling of this space, to increase the quantity of usable bone (grafts...).

Adolescent↗

[Application of a new vascular injection technique in the study of the infratemporal region].

The infra-temporal region (ITR) is an anatomically rich region thanks to its arterial and venous divisions and large nerve crossroads. It is also, as described by Robert et al". in a publication about the ITR, (22) "the hidden face of the manductory apparatus. The ITR is therefore a passageway for a large number of anatomical elements and its complexity makes it a particularly delicate region for daily surgical practice. For these many reasons the anatomical study of the ITR, which has already been the origin of a number of works, seemed interesting to us, and more particularly combined with the use of an original injection material, Odongel. The injection of this material, in the arterial as well as the venous system, enabled us to improve our dissections thanks to its flexibility, elasticity, its case-of-use and its speed of preparation. The complexity and richness of the region meant that in order to study it anatomically we had to focus on a specific anatomical element for each dissection session, especially at the beginning. After having used traditional products such as resins (methyl methacrylate), latex and even the too rigid silicon elastomers, Odongel seemed interesting to us because it is very easier to use it. The purpose of this study was to prove that Odongel is an efficient material, working equally well for both the arterial and venous systems irrespective of the diameter of the vessels concerned. It can become an alternative to the other injection products in some situations. Finally, in the case of the ITR, an extension of the existing techniques used in anatomical studies coupled with an increase in anatomical precision could improve our knowledge of this zone and eventually facilitate certain surgical interventions.

Aged↗

Bronchial asthma and self-management education: implementation of Guidelines by an interdisciplinary programme in health network.

UNLABELLED: Asthma is a chronic disease generating very high costs even for Switzerland. Self-management education (SME) is effective and recommended as an integral part of management in the most recent guidelines on asthma treatment. Its aim is to reduce morbidity [hospitalisations (H), lost workdays (LW), emergency consultations (EC)] and improve quality of life (QOL) in these patients. METHOD: Integrated programme with educational platforms (two-language booklet), SME in 66 patients (30 m, 36 f) with interdisciplinary quality team (pneumologists, primary care physicians, pharmacists, specialised nursing staff), QOL questionnaire. Measurement of morbidity parameters 12 months before and after SME. Measurement of QOL before and 12 months after SME. RESULTS: Hospitalisations fell from 35 to 8%*, EC from 88 to 53%*. and LW from 39 to 14%* (*p <0.001). Overall, SME resulted in a health cost saving of CHF 202,510 in terms of LW and CHF 131,200 in terms of days in hospital, i.e. a total of CHF 333,710. Costs saved per patient were CHF 5,056 per year. QOL improved with the following scores: overall QOL 4.5 +/- 0.9 to 5.2 +/- 0.9*; activities 4.5 +/- 0.9 to 5.2 +/- 0.9*; symptoms 4.2 +/- 1.1 to 5.2 +/- 1.1*; emotions 4.9 +/- 1.1 to 5.6 +/- 1*; environment 4.5 +/- 1.4 to 4.9 +/- 1.3* (*p <0.001). CONCLUSION: SME by interdisciplinary health network is effective. It brings a steep fall in costs for asthma treatment by cutting back hospitalisations and lost workdays and by improving the asthmatics' quality of life. It should be recognised and better supported by the health system.

Adolescent↗

Study of the relationship between the suprascapular artery and the brachial plexus.

The literature concerning the relationship of the suprascapular artery with the brachial plexus is quite limited. The aims of this study were to investigate the different types of relationships between the suprascapular artery and the brachial plexus trunks and to try to clarify their prevalence in the European population. Our study involved the dissection of 100 upper extremities from adults, all of European origin (55 women, 45 men). In the classic description, the suprascapular artery passes in front of the brachial plexus (group A) in the majority of cases, then behind the omohyoid before reaching the superior border of the scapula. There are two other types of relationship with the brachial plexus: the suprascapular artery can pass between the trunks of the brachial plexus (group B) or the artery can pass behind the brachial plexus (group C). To our knowledge there has been only one study on the subject, carried out by Kosugi et al. Our results show a not inconsiderable number of variations in the relationships between the suprascapular artery and the brachial plexus (29%). Although no differences were noted between the sexes, a significant number of individual variations were revealed by the comparative study of dissections performed on both upper extremities of the same individual. Our results suggest that new studies are required to complete these initial anatomical results observed on a small sample of subjects of European origin. The French version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00276-002-0026-5.

Arteries↗

Influence of prone position on gastric mucosal-arterial PCO2 gradients.

OBJECTIVE: To evaluate the effects of mechanical ventilation in the prone position on gastric mucosal-arterial PCO2 gradients. DESIGN: Prospective clinical study. SETTING: Intensive care unit in a university clinic. PATIENTS: Twenty-five patients requiring mechanical ventilation. The physician in charge indicated the turning manoeuver for the individual patient. MEASUREMENTS/RESULTS: In addition to routine measurements of global hemodynamics and gas exchange we determined: 1) intragastric pressure; and 2) gastric mucosal-arterial PCO2 difference. After a baseline measurement in the supine position patients were turned to the prone position. After 60', 120', a median of 6.5 h (2-10 h) in the prone position, and again after 60' in the supine position, all measurements were repeated. Global hemodynamics remained unaltered throughout the study. While gastric mucosal-arterial PCO2 gradients did not change significantly during the first 60 min in the prone position, they significantly increased during the following 60 min [median/percentile: baseline: 6 (1 to -3); 60': 7 (15-5); 120': 13 (20-8) mmHg]. The median intragastric pressure was not significantly affected [baseline: 10 (13-5); 60': 12 (16-8); 120': 11 (13-7) mmHg], but 9 of the 11 patients in whom intragastric pressure increased during the first 60 min in the prone position also showed significantly increased PCO2 gradients (P < 0.01). CONCLUSION: Mechanical ventilation in the prone position may be affiliated with increased tonometric gastric mucosal-arterial PCO2 gradients depending on the effect on intraabdominal pressure. Measuring intraabdominal pressure and/or gastric mucosal PCO2 via a nasogastric tube therefore may help to detect adverse effects of this ventilatory strategy.

Analysis of Variance↗

Anatomical basis of latissimus dorsi and teres major transfers in rotator cuff tear surgery with particular reference to the neurovascular pedicles.

Musculotendinous transfers (MTT) of latissimus dorsi (LD) and teres major (TM), either in isolation or combination, have recently been advocated to treat irreparable rotator cuff tears. The purpose of this study was to (1) review the anatomy of the LD and TM neurovascular pedicles, and (2) undertake experimental MTT to humeral insertions of either supraspinatus or infraspinatus to evaluate tension on their nutrient arteries in six positions of the arm. Twenty-six shoulders were studied, 22 of which had previously been injected with red latex. Gross dissection, using 4.3 x magnification when necessary, was followed by one MTT for each shoulder (11 LD, 6 TM, 9 combined). The anatomy of the LD and TM neurovascular pedicles was consistent with classic descriptions in 85% of cases; "medialisation" of the thoracodorsal artery was observed in 4 specimens. Tension on the teres major artery was not observed in 15 isolated or combined MTTs, while tension on the thoracodorsal artery in at least one arm position was observed in 60% of 20 isolated or combined MTTs. Three factors were found to be associated with tension: medialisation of the thoracodorsal artery, fixation onto the supraspinatus insertion, and 90 degrees abduction combined with internal rotation. The results suggest that tension on the thoracodorsal artery is possible under certain circumstances when an isolated LD or combined MTT is performed to treat irreparable rotator cuff tear.

Adult↗

Are meiofauna transient or resident in sand filters of marine aquariums?

A paradoxical situation was found in the sand filters of a cold marine mesocosm: meiofaunal masses which were large enough to inhibit the mineralization and nitrification processes coexisted with nitrogen cycling bacteria. To test whether the copepod-dominated meiofauna were resident and actively feeding or transient and carried passively through the sand filters, residence times (RTs) were measured for various meiofaunal groups in a newly started filter and in a long established one. Most meiofauna colonized the newly started filter in less than 6 h, but their RTs were less than 24 h. In contrast, RTs were 147d for halacarids, 291 d for harpacticoid copepods and 1228d for nematodes in the long established filter. Mesocosm periphyton. which occupied a large fraction of the mesocosm surface area and was characterized by high meiofaunal densities, was probably the main source of meiofauna in the sand filters. Pool sediments, consisting of gravel or sand, were second to periphyton and contributed hydrozoans and mesopsammic species to the filters. The small copepod Pseudonychocamptus proximus progressively replaced the large Tisbe furcata in sand filters during the fall of 1995 and was responsible for the large increase in meiofaunal biomass observed after spring 1996. This replacement was presumably facilitated by the copepod size selection process operated by the filters. Large copepods were retained by the surface layer of sand or brought up by the backwash water and then exit the mesocosm through the drain. High meiofaunal populations did not significantly affect nitrogen cycling bacteria in sand filters probably because meiofauna also fed on other abundant food sources which were carried in by the water flow.

Animals↗

Phenotypic and genotypic characterization of esterase-producing Ureibacillus thermosphaericus isolated from an aerobic digestor of swine waste.

Eight closely related thermophilic strains were isolated from an aerobic and thermophilic treatment of swine wastes. The pleomorphic cells (short and long rods; cocci) showed peritrichous flagella, terminally swollen sporangium, and liberated spores exhibiting hairy appendages. The Gram reaction was negative for both young (4 h) and old (48 h) cultures. Several features, such as colonial morphology, growth between 35 degrees C and 65 degrees C, presence of catalase, presence of spores, and strictly aerobic metabolism (except for one strain), are similar to those found for the genus Bacillus. The inability of the strains to use sugars, except esculin, as source of carbon and energy and the whole cell fatty acid composition are similar to those found in Bacillus thermosphaericus DSM 10633. Sequence analysis of the 16S rRNA gene revealed 99.8%-99.9% identity for seven of the thermophilic strains with this species. A new genus, Ureibacillus, was recently proposed for type strain B. thermosphaericus DSM 10633 The last strain exhibits 97.8% and 97.3% identity with Ureibacillus terrenus DSM12654 and Bacillus sp. TP-84, respectively. Esterase activities were detected for all strains, and assays on p-nitrophenyl butyrate and p-nitrophenyl caprylate revealed that strains were more active on the shorter substrate.

Aerobiosis↗

[Effect of estrogen therapy on the growth of Turner syndrome in girls treated with growth hormone].

Two groups of patients with Turner Syndrome (TS) were studied to analyse the effect of estrogens on their growth. Group 1 (G1): 14 patients treated with growth hormone (GH) who started estrogens (SO) (Premarín) at 15.3 +/- 0.9 years old. Group 2 (G2): 10 girls not treated with GH who started Premarín at 14.3 +/- 2.3 years old. Height SDS improvement in periods of time of GH and GH plus estrogen treatment was evaluated and compared between both groups. The gain in stature during estrogen therapy (final height-projected height at SO) was calculated. In G1 multiple regression was used to examine factors influencing the gain in stature during GH treatment (final height-projected height at the start of GH): bone age at the SO, chronological age at the SO and the time of GH treatment prior to SO. In G1 the height SDS improvement was 0.43 +/- 0.11 cm during GH treatment and 0.59 +/- 0.18 cm during GH plus oestrogens (p = 0.064). The height SDS improvement during estrogen therapy in G2 was 0.14 +/- 0.19 cm, smaller than in G1 (p < 0.001). Gain in stature during estrogen therapy was 5.3 +/- 1.8 cm in G1 and -0.6 +/- 4.2 cm in G2 (p = 0.001). In G1 the time of GH treatment prior to SO was the strongest predictor of the gain in stature during GH treatment (r = 0.89).

Adolescent↗

[Venous drainage and innervation of the maxillary sinus].

The maxillary sinus, or "Highmore's antrum", is a cavity of the facial structure buried in the body of the maxillary body joined to the nasal fossae with which it communicates via the maxillary ostium. The dissection of 25 maxillary sinuses has enabled us to study its venous drainage and innervation. The venous system is collected either by a single trunk, which is a continuation of the spheno-palatine vein, or by three venous plexus: the anterior and posterior pterygoid plexus, and the alveolar plexus. The anterior and posterior pterygoid plexus converge through the lateral pterygoid muscle and connects with the alveolar plexus which drains partly into the maxillary vein and partly into the facial vein. The innervation of the maxillary sinus is ensured by the maxillary nerve (V2): the second branch of the trigeminal nerve and its collateral branches. During the course of its track the maxillary nerve becomes successively the spheno-palatine nerve and the anterior orbital nerve, and gives rise to some collateral branches: the posterior and superior alveolar ramus, the medium and superior alveolar nexus and the anterior and superior alveolar ramus.

Cadaver↗

Redundant thyroid laboratory diagnostic modules in laboratory information system--a way to improve the performance.

In this paper, we introduced an idea of using redundant thyroid laboratory diagnostic modules integrated in laboratory information system. The first module was based on decision tree which was the result of Assistant algorithm applied to thyroid laboratory test results. Instead of improving decision rules, the "second opinion" module was designed based on Spad-S software. Diagnosis obtained with both modules were compared with results before introducing the "second opinion" module. From the first results it was clear that introducing the "second opinion" module decreased the number of misclassified records from the first module. With three or more modules, the final diagnosis could be obtained by voting or more complex procedures.

Algorithms↗