Biomedical subjects

A Morin

Publications and source records attributed to A Morin.

At least 37 records · Page 2Linked to original sources

PubMed2000

[Prediction of final height in girls with Turner syndrome treated with growth hormone].

Treatment with growth hormone (GH) in girls with Turner syndrome (TS) would improve growth velocity (GV) and final height (FH) prediction. A total of 21 girls with TS treated with GH for 1 (n = 21), 2 (n = 18) and 3 years (n = 10) were studied. At the onset of GH treatment, the mean chronological age was 11.6 +/- 2.6 years and the mean bone age was 9.7 +/- 2.4 years. The mean height SDS was: -0.04 +/- 1.0 at the beginning, 0.4 +/- 1.0 at 1st year, 0.9 +/- 1.1 at 2nd year and 1.25 +/- 0.56 at 3rd year of treatment (p = 0.0001, p < 0.0001 and p < 0.05 respectively). The mean GV SDS was 1.6 +/- 1.8 at the beginning, 2.5 +/- 1.7 at 1st year, 3.8 +/- 2.9 at 2nd year and 2.2 +/- 2.0 at 3rd year (p = 0.01, p = 0.04 and p = 0.29 respectively). The FH prediction by Bayley-Pinneau method was: 142.8 +/- 5.2 cm at the beginning, 143.8 +/- 6.0 at 1st year, 146.0 +/- 5.9 at 2nd year and 145.6 +/- 6.4 at 3rd year (p = 0.026, p = 0.05 y p = 0.87 respectively). The mean ending height treatment (EH), in 8 patients, was 145.1 cm +/- 6.7. In conclusion, 1) studied patients showed systematic bone age delay at the beginning of GH treatment; 2) during the treatment, GV increment and improvement in relative heights and in FH prediction were observed; 3) the EH, nearest to the FH prediction, previously made at 3rd year of treatment, was 7.2 cm higher than mean FH's for Argentinean girls with TS without GH treatment.

Body Height↗

PubMed1999

Origin of the serotonergic innervation to the rat dorsolateral hypothalamus: retrograde transport of cholera toxin and upregulation of tryptophan hydroxylase mRNA expression following selective nerve terminals lesion.

The regulation of serotonin synthesis was investigated in the serotonergic neurons, which provide afferents to the dorsolateral hypothalamus (DLH). The origin of the DLH projection neurons within the raphe nucleus was identified by retrograde transport of Cholera toxin (CTb) and their serotonergic nature confirmed by tryptophan hydroxylase (TPH) immunocytochemistry. Disruption of serotonin synthesis steady-state was induced unilaterally by a selective and local destruction of serotonergic nerve terminals with 5,7-dihydroxytryptamine (5,7-DHT), stereotaxically injected in the right DLH. The results show that most of the serotonergic dorsal raphe neurons projecting to the DLH have an ipsilateral localization within the lateral aspects of the nucleus. In rats with unilateral DLH lesion, a population of serotonergic cells within the raphe nucleus exhibited a clear increase in TPH mRNA. These cells were about five times more numerous in the ipsilateral as compared to the contralateral dorsal raphe nucleus and they had, for the most part, a lateral localization within the raphe nucleus. Sham-operated rats did not exhibit any upregulation of TPH mRNA. Together, the present results provide the first demonstration that a discreet and selective destruction of serotonergic terminals induces a circumscribed and striking increase in TPH mRNA expression in a subset of brainstem serotonergic neurons projecting to and/or passing through the DLH. On the basis of these results and previous in vivo measurements of TPH activity (e.g., 5-HT synthesis), we suggest that this upregulation in TPH mRNA expression results from the loss of pre-synaptic and/or post-synaptic regulation of serotonin synthesis. These new findings raise important issues related to the repercussions of a local disruption in serotonergic neurotransmission on brain areas remote from the site of injury.

5,7-Dihydroxytryptamine↗

PubMed1999

French mirror site of the NPAC visible human viewer: first year evaluation.

The NPAC visible human viewer (NPAC VHV), graphical interface written in JAVA, freely accessible by the Web, allows the display of anatomic cross-sections of the Visible Human Project developed by the National Library of Medicine. In April 1997, the Medical Media Library of Lyons undertook the construction of a French-language mirror site of the NPAC VHV. The aim of this work is to evaluate first year utilisation of this site. From May 1st, 1997 to April 30th, 1998, the mirror site was consulted 34,752 times. In 45.14% of cases, the request came from France, in 4.42% of cases from Belgium, in 3.98% from Canada and in 2.12% from Switzerland. Other connections came either from a country responsible for fewer than 1% of connections or from unidentified computers. Data analysis showed a peak of connections between 15:00 and 17:00, and an increased number of connections from September to March 1998. The NPAC VHV is housed in 5 sites in the world. It is a software very simple to use. As the figures have no legends, it is more appropriate for group teaching than for self-teaching.

Anatomy, Cross-Sectional↗

PubMed1999

Effect of growth temperature on hydrolytic and esterifying activities from pseudomonas fragi CRDA 037 grown on whey

The production of hydrolytic and esterifying activities of Pseudomonas fragi CRDA 037 grown on a whey-based medium was investigated at different temperatures over time. The optimal temperature was found to be critical and different for the production of both activities. The highest hydrolytic activity was detected with bacteria cultivated at between 24 degrees C (149.2 U/liter) and 27 degrees C (133.8 U/liter), while the highest production of ethyl valerate (esterifying activity) was observed by using biomass grown at 15 degrees C (0.75 U/liter). When the fermentation temperature was increased, the incubation time necessary to reach the maximal concentration of both activities was reduced. Studies of the thermostability of both activities showed that the hydrolytic activity was more stable than the esterifying activity at 15 and 24 degrees C. Statistical analysis allowed the determination of the equations that predicted the production of hydrolytic and esterifying activities as a function of time and growth temperature. The optimal assay temperatures for the hydrolytic and esterifying activities were 37 degrees C and 12 to 15 degrees C, respectively.

Journal Article↗

PubMed1999

[Anatomical study of the interosseous membrane of the forearm].

The authors have dissected 20 forearms of human cadavers to study anatomy and some functions of the IOM. The fibers bundles of the IOM were arranged in one plane descending obliquely and distally from the radius to insertion to the ulna. Central band of the IOM was easily found and was thick. It's a resistant ligament for longitudinal stability of the radius. Now, it's important to know anatomical alignment of the IOM because ultrasound imaging can be used for diagnosis of its rupture or elbow injuries and in a early future, surgical methods of repair or reconstruction of IOM will be developed.

Forearm↗

PubMed1998

Structural requirements for enzymatic formation of threonylcarbamoyladenosine (t6A) in tRNA: an in vivo study with Xenopus laevis oocytes.

We have investigated the specificity of the eukaryotic enzymatic machinery that transforms adenosine at position 37 (3' adjacent to anticodon) of several tRNAs into threonylcarbamoyladenosine (t6A37). To this end, 28 variants of yeast initiator tRNAMet and yeast tRNAVal, devoid of modified nucleotide, were produced by in vitro transcription with T7 polymerase of the corresponding synthetic tRNA genes and microinjected into the cytoplasm of Xenopus laevis oocytes. Threonylcarbamoyl incorporation was analyzed in tRNA transcripts mutated in the anticodon loop by substitution, deletion, or Insertion of nucleotides, or in the overall 3D structure of the tRNA by altering critical tertiary interactions. Specifically, we tested the effects of altering ribonucleotides in the anticodon loop, changes of the loop size, perturbations of the overall tRNA 3D structure due to mutations disruptive of the tertiary base pairs, and truncated tRNAs. The results indicate that, in addition to the targeted A37, only U36 was absolutely required. However, A38 in the anticodon loop considerably facilitates the quantitative conversion of A37 into t6A37 catalyzed by the enzymes present in X. laevis. The anticodon positions 34 and 35 were absolutely "neutral" and can accept any of the four canonical nucleotides A, U, C, or G. The anticodon loop size may vary from six to eight nucleotides, and the anticodon stem may have one mismatch pair of the type AxC or GxU at location 30-40 without affecting the efficiency of t6A37 formation and still t6A37 is efficiently formed. Although threonylcarbamoylation of A37 occurred with tRNA having limited perturbations of 3D structure, the overall L-shaped architecture of the tRNA substrate was required for efficient enzymatic conversion of A37 to t6A37. These results favor the idea that unique enzymatic machinery located in the oocyte cytoplasm catalyzes the formation of t6A37 in all U36A37-containing tRNAs (anticodon NNU). Microinjection of the yeast tRNAMeti into the cytoplasm of X. laevis oocytes also revealed the enzymatic activities for several other nucleotide modifications, respectively m1Gg, m2G10, m(2)2G26, m7G46, D47, m5C48/49, and m1A58.

Adenosine↗

PubMed1998

[Resistance of the the coraco-clavicular ligaments to traction: clinical application].

One method for treating chronic incapacitating acromioclavicular dislocation is to resect the external extremity of the clavicle and to stabilise the stump by ligamentoplastic procedures, using the coracoclavicular ligament. The purpose of this work was to evaluate the mechanical quality of the ligamentoplastic approach. Twelve fresh cadavers, average age 80 years, were studied. The samples taken were 24 coracoclavicular ligaments, 24 coraco-acromial ligaments, 9 tendons from the palmaris longus muscle and 9 iliotibial tracts. The ligaments removed were tested in a Instron traction machine at a speed of 10 cm/mn. The mechanical properties of the coracoclavicular and coraco-acromial ligaments were studied. For comparison, those of the tendon of the palmaris longus muscle and the iliotibial tract were also studied. The results show the pre-rupture resistance of the coraco-acromial ligament to be 50% lower than that of the trapezoid and conoid parts of the coracoclavicular ligaments taken together. These results suggest the validity of ligamentoplastic treatment using the coraco-acromial ligament, but that reinforcement, using a tendon from the palmaris longus muscle or a piece of the iliotibial tract, may also be necessary, especially for subjects taking part in sports or with well-developed musculature.

Acromioclavicular Joint↗

PubMed1997

[Anatomic study via dissection of the common fibular nerve: etiopathogenic consideration].

In order to understand and prevent the particular rate of the common fibular nerve palsy during the traumatisms of the main stem of the sciatic nerve; the authors have studied through dissection the osteomuscular and aponeurotic relationships of 38 common fibular nerves. They blame it on the relations between the nerve and the proximal ends of the fibula; the nerve can be stretched on and mainly on its fixation on the crural fascia by fibrous tracts seen in 78.94 of the cases.

Adult↗

PubMed1996

Effects of the N-terminal cysteine mutation on prolactin expression and secretion in transfected cells .

We developed an experimental cell model to look for motif(s) of rat PRL sequence encoding a sorting signal to secretory granules. An efficient expression vector (pCMV-rPRL) was used to transfect several eukaryotic cell lines in culture, i.e., one neuronal cell line (C6) and three glandular pituitary derived cell lines (AtT20, GC, GH3CDL). Despite the ubiquitous transcription of pCMV-rPRL, the synthesis and secretion of rPRL were detected primarily in GH3CDL cells that derived from lactotrophs, suggesting a cell-specific post-transcriptional control of rPRL expression. During transient expression, exogenous native PRL was transported through intracellular compartments of the secretory pathway and underwent regulated release. Abolition by mutagenesis (C4S) of the N-terminal disulfide bond increased by 50% the PRL secretion rate (medium to cell ratio) and multiplied by 5 the specific activity of medium PRL from pulse-labeled cells. These results support the hypothesis that N-terminal disulfide bond plays a role in the control of PRL intracellular transit and storage.

Animals↗

PubMed1996

Trypanosoma cruzi: study of the distribution of two widespread clonal genotypes in Bolivian Triatoma infestans vectors shows a high frequency of mixed infections.

The detection of two widespread Trypanosoma cruzi clonal genotypes (20 and 39) in feces of Bolivian specimens of the vector Triatoma infestans was performed by a combination of polymerase chain reaction and clone-specific DNA hybridization. The hybridization pattern of 186 PCR positive samples cf T. infestans feces collected in two Bolivian departments identified clone 20 in 74.2% and clone 39 in 63.4% of the triatomine bugs. For the first time, a high percentage (mean: 43.2 +/- 26%) of mixed infections (presence of both clones in a given fecal sample) in various localities was recorded. Results were in agreement with the two assumptions of independent transmission of clones 20 and 39 and of the absence of selection in the natural cycles under survey. Statistical analysis of the geographical distribution of clones 20 and 39 favored the hypotheses that the frequencies of T. cruzi natural clones are different among localities and that these differences are not proportional to the distances that separate the localities. The epidemiological significance of these results is discussed.

Animals↗

PubMed1996

Enzymatic conversion of adenosine to inosine and to N1-methylinosine in transfer RNAs: a review.

Inosine (6-deaminated adenosine) is a characteristic modified nucleoside that is found at the first anticodon position (position 34) of several tRNAs of eukaryotic and eubacterial origins, while N1-methylinosine is found exclusively at position 37 (3' adjacent to the anticodon) of eukaryotic tRNA(Ala) and at position 57 (in the middle of the psi loop) of several tRNAs from halophilic and thermophilic archaebacteria. Inosine has also been recently found in double-stranded RNA, mRNA and viral RNAs. As for all other modified nucleosides in RNAs, formation of inosine and inosine derivative in these RNA is catalysed by specific enzymes acting after transcription of the RNA genes. Using recombinant tRNAs and T7-runoff transcripts of several tRNA genes as substrates, we have studied the mechanism and specificity of tRNA-inosine-forming enzymes. The results show that inosine-34 and inosine-37 in tRNAs are both synthesised by a hydrolytic deamination-type reaction, catalysed by distinct tRNA:adenosine deaminases. Recognition of tRNA substrates by the deaminases does not strictly depend on a particular "identity' nucleotide. However, the efficiency of adenosine to inosine conversion depends on the nucleotides composition of the anticodon loop and the proximal stem as well as on 3D-architecture of the tRNA. In eukaryotic tRNA(Ala), N1-methylinosine-37 is formed from inosine-37 by a specific SAM-dependent methylase, while in the case of N1-methylinosine-57 in archaeal tRNAs, methylation of adenosine-57 into N1-methyladenosine-57 occurs before the deamination process. The T psi-branch of fragmented tRNA is the minimalist substrate for the N1-methylinosine-57 forming enzymes. Inosine-34 and N1-methylinosine-37 in human tRNA(Ala) are targets for specific autoantibodies which are present in the serum of patients with inflammatory muscle disease of the PL-12 polymyositis type. Here we discuss the mechanism, specificity and general properties of the recently discovered RNA:adenosine deaminases/editases acting on double-stranded RNA, intron-containing mRNA and viral RNA in relation to those of the deaminases acting on tRNAs.

Adenosine↗

PubMed1996

Use of continuous culture to screen for lipase-producing microorganisms and interesterification of butter fat by lipase isolates.

The continuous cultivation technique was used to investigate the screening for lipase-producing microorganisms from four commercial starters suitable for the degradation of domestic wastes. Using this technique, three strains of lipase-producing bacteria were isolated and identified: Pantoea agglomerans (BB96CC1, BB168CC2) and Pseudomonas fluorescens (BW96CC1). In addition, butter fat induced more lipase production when present in the growth medium. Interesterification of butter fat triacylglycerols by enzymatic extracts of the isolated strains of microorganisms resulted in an appreciable interesterification yield, implying that hydrolysis was suppressed and interesterification of butter fat triacylglycerols was maximized in a microemulsion free-cosurfactant system.

Biodegradation, Environmental↗

PubMed1996

[Teratology "from Geoffroy Saint-Hilaire to the present"].

Teratology, science of monsters, exists during the periods of Antiquity, Middle Ages, Renaissance, ... but its comes more precise at the XIXth century with Etienne. Geoffroy Saint Hilaire who studies several anomalies; he was interested in celosomia, cyclocephalia, anencephaly, twin monsters ... His son, Isidore Geoffroy Saint Hilaire, creates the word "Teratologie" and specifies the teratologic classification; he studies omphalosites, celosomia, hermaphrodite, twin monsters. During the XIXth century, the development of experimental embriology and teratogenesis is very important. During le XXth century the studies of morphologic teratology are specified. Famous living monsters are described; experimental teratogenese is improved; the mecanism and the etiology are more known. It is also the beguining of the teratologic surgery and of the antenatal diagnostic.

Belgium↗

PubMed1995

Lipase from Pseudomonas fragi CRDA 323: partial purification, characterization and interesterification of butter fat.

Several strains of Pseudomonas were screened for lipase production using the rhodamine agar diffusion test. On the basis of the diameter of the halo produced, P. fragi CRDA 323 and P. putida ATCC 795 were considered to be good and weak lipase producers respectively. P. fragi, cultured in a 2-l fermenter, produced a maximal amount of lipase after 3-4 days of incubation at 27 degrees C. The lipase extract of P. fragi was obtained by acidification of culture supernatant at pH 4.0 and partially purified with ammonium sulphate precipitation. The majority of lipase activity (42%) was located in fraction IV, precipitated at 20%-40% of saturation, with a 19-fold enzyme purification. The Km and Vmax values for the partially purified enzymatic extract (fraction IV) were 0.70 mg/ml and 0.97 x 10(-3) U/min respectively. Fraction IV, which showed an optimum activity at pH 8.5, was used for the interesterification of butter fat in a microemulsion free co-surfactant system containing Span 60 (sorbitol monostearate) and Tween 60 (polyoxyethylene sorbitan monostearate) in the ratio 48:52 (v/v). The results showed that the interesterification of butter fat resulted in a considerable decrease in long-chain saturated fatty acids (C12:0, C14:0 and C16:0) with a concomitant increase in C18:0 and C18:1 at the sn-2 position of selected triacylglycerols. In addition, the results demonstrated an increase in the fatty acids (C12:0, C14:0 and 16:0) among the 1 and 3 positions of the triacylglycerol molecules of modified buffer fat accompanied by a decrease in C18:0 and C18:1.

Butter↗

PubMed1995

Use of a polymerase-chain-reaction-amplified DNA probe from Pseudomonas putida to detect D-hydantoinase-producing microorganisms by direct colony hybridization.

Pseudomonas putida strain DSM 84 produces N-carbamyl-D-amino acids from the corresponding D-5-monosubstituted hydantoins. The sequence of the D-hydantoinase gene from this strain (GenBank accession number L24157) was used to develop a DNA probe of 122 base pairs (bp) that could detect D-hydantoinase genes in other bacterial genera by DNA and by colony hybridization. Under conditions tolerating 32% mismatch, the probe was specific for all strains that expressed D-hydantoinase activity. These include Pseudomonadaceae of all rRNA groups, and bacteria belonging to the genera Agrobacterium, Serratia, Corynebacterium, and Arthrobacter. Environmental sampling was simulated by screening a mixture of unknown microorganisms from commercial inocula for the biodegradation of industrial, municipal and domestic wastes. The 122-bp probe was specific for microorganisms that subsequently demonstrated D-hydantoinase activity. Bacterial species from four different genera were detected, which were Pseudomonas, Klebsiella, Enterobacter, and Enterococcus.

Amidohydrolases↗

PubMed1995

Preliminary data on a relation between self-talk and complexity of the self-concept.

Recent empirical work in social cognition suggests that in building a self-concept people make inferences about themselves based on overt behavior or private thoughts and feelings. This article addresses the question of how, exactly, people make these inferences about themselves and raises the possibility that they do so through self-talk. It is proposed that the more on talks to oneself to construct a self-image, the more this image will gain coherence and sophistication. A correlational study was conducted to explore the relation between richness of the self-concept (using the W-A-Y) and natural disposition to talk to oneself (using a pilot questionnaire). A moderate but positive correlation of .30 is obtained. The article concludes with clinical implications.

Adult↗

PubMed1995

[Analysis of restraint of the femur head. Experimental study of allograft of cold bone and autoclaved bone to kill the HIV virus].

The retrovirus S.I.A.D. grown in marrow bone and iatrogenic infections may be possible after bone graft in following total hip arthroplasties. Previous investigators proposed several methods to kill the virus, but without bacteriological safety. They found 20 to 55% of loss on mechanical properties. The present study reports the response of autoclaved femoral heads compression testing on material machine Model 1026 Instron. The stress response of marrow bone to stains showed a classic peak and with linear regression study we saw a relationship between autoclaved bone and cold bone. The cortical bone resists to strains highly 12% of load.

Aged↗

PubMed1995

[The arteries of the stomach].

In order to specify the gastric-arterial systematization, 65 fresh stomachs of adults deceased from non-gastro-duodenal causes, extracted by necropsy, allowed us to study the arteries of the stomach through the injection-corrosion technics. A selective injection for each arterial trunk has been made on 15 stomachs. This work allowed us to know better the arterial supply of the stomach and ut into obviousness important vascular anastomosis. While emphasizing on the substitute notion, the persons who wrote this summary describe regions poor in anastomosis, which correspond surgically with "critical" areas. They also emphasize how important it is to have an estimated score of the ischemia for gastric surgery, especially in the case of oeso-gastroplasty.

Adult↗