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M Nogues

Publications and source records attributed to M Nogues.

17 recordsLinked to original sources
PubMed2003

Synthesis, structure, and magnetic properties of two new vanadocarboxylates with three-dimensional hybrid frameworks.

(V(III)(OH))(2)[C(6)H(2)(CO(2))(4)].4H(2)O (labeled MIL-60) and V(III)(OH)[(2)(O(2)C)C(6)H(2)(COOH)(2)].H(2)O (labeled MIL-61) were hydrothermally synthesized from mixtures of VCl(3), 1,2,4,5-benzenetetracarboxylic acid, and water heated for 3 days at 473 K. The structure of MIL-60 was solved from single-crystal X-ray diffraction data in the triclinic centrosymmetric P1 (No. 2) space group with lattice parameters a = 6.3758(5) A, b = 6.8840(5) A, c = 9.0254(5) A, alpha = 69.010(2) degrees, beta = 85.197(2) degrees, gamma = 79.452(2) degrees, V = 363.53(5) A(3), and Z = 1. The structure of MIL-61 was ab initio determined from an X-ray powder diffraction pattern. MIL-61 crystallizes in the Pnma (No. 62) orthorhombic space group with lattice parameters a = 14.8860(1) A, b = 6.9164(1) A, c = 10.6669(2) A, V = 1098.23(3) A(3), and Z = 4. Both structures contain the same inorganic building block that consists of trans chains of V(III)O(4)(OH)(2) octahedra. The three-dimensional frameworks of MIL-60 and MIL-61 are constituted by the linkage of these chains via the organic molecules so delimiting the channels or cages where the water molecules are encapsulated. The magnetic behavior of these two phases is presented: MIL-60 is paramagnetic, and MIL-61 antiferromagnetically orders below T(N) = 55(5) K.

Journal Article↗
PubMed2003

[Prospective epidemiological study on cutaneous melanomas in the Vendée area].

INTRODUCTION: The aim of this prospective study was to evaluate the incidence of melanoma in the Vendée area, coastal region of Eastern France, in 1997. PATIENTS AND METHODS: The 16 dermatologists in the Vendée area in 1997, grouped together in a local association, completed a sheet for each patient in whom a new melanoma had been diagnosed. During the same period, the hospital and private pathologists of the Vendée and surrounding areas reported their new cases of melanoma in patients residing at least six months of the year in the area. The data concerning the local population was supplied by the INSEE (French national institute of economic and statistical information) and the CPAM (French health authority) supplied data on the practitioners' activity. The raw and standardized incidence was calculated by the epidemiologist and the statistician of the local Vendée Cancer registry. RESULTS: One hundred fifteen new melanomas were diagnosed in Vendée in 1997, 97 by a dermatologist and 18 declared by a pathologist. There were 36 in situ and 79 invasive melanomas discovered in 68 women and 47 men (sex ratio: 1.46). The standardized rate of incidence according to the world model was of 98/100,000 for women and 7.8/100,000 for men. The frequency curve revealed two peaks: the first at 40-50 years of age and the second at 70-75. The mean Breslow index of the 79 invasive cancers was of 1.62 mm (range: 0.10-12.5 mm). The only statistically significant difference between the melanomas of the men and the women concerned the topography; there were more melanomas on the trunk in men and more melanomas on the lower limbs in the women. Forty-seven Dubreuilh melanomas were reported: 28 in situ and 19 invasive. DISCUSSION: This prospective study determined the incidence of melanoma in Vendée in 1997. The figures have been compared with those of the Vendée cancer registry, founded in April 1997, and with those of various published studies. The comparison was difficult because of the difference in study methodology. The only figures obtained in the same conditions are those of the cancer registry and we compared them with those of the Haut-Rhin, area of Eastern France: the incidence was similar for the women in the two areas and greater for the men in the Haut-Rhin with regard to the invasive melanomas. Conversely, 44 in situ melanomas were declared in the Haut-Rhin over a 3 year period versus 37 in Vendée over a period of 1 year. The increase in the incidence of melanoma in Vendée in the years to come should permit the evaluation of the impact of the various preventive campaigns.

Adult↗
PubMed2003

[Prospective clinical study on new cutaneous melanomas in the Vendée area].

INTRODUCTION: In parallel to an epidemiological study on the new cases of melanoma reported in the Vendée area in 1997, private dermatologists conducted a clinical analysis of the characteristics of melanomas (including Dubreuilh's melanoma) and of the population concerned. PATIENTS AND METHODS: For each patient in whom a melanoma had been diagnosed, the dermatologists completed a standardized sheet that included the identification, phototype (comparing the distribution with that of the local population, studied in all the consultants during a randomly selected week), the personal and family history of melanoma, the existence of severe sunburn and exposure to artificial ultra-violet rays, the screening method, the time lapse before treatment, the impact of information campaigns, the number of nevi, atypical or not, and the characteristics of the tumor. The exeresis method and the histological characteristics (type, Clark's score and Breslow's index) were also noted. RESULTS: In 1997, the 16 local dermatologists diagnosed 97 melanomas in 55 women and 42 men with a mean age of 64 years. There was no statistically significant difference between the melanomas of the men and those of the women, other than their localization. Photoype II was significantly more frequent in the population exhibiting a melanoma. Sun exposure was moderate or intensive for three thirds of the patients. Past history of severe sunburn was twofold more frequent in the patients exhibiting a melanoma on the trunk. The association of many nevi was noted in a little more than half of the patients, and with atypical nevi in 5.2 p.cent. The elements that alerted the patients were recorded. The time lapse before diagnosis was calculated in months for nodular and in years for superficial melanomas. Clark's score and Breslow's index are presented in a table. DISCUSSION: Our study underlines several interesting features: the fairly high mean age on discovery, a high rate of invasive melanomas, and patients less well informed than in the Ile de France area. These results should open the debate on the best way to educate the population concerned so as to reduce the incidence of this malignant tumor.

Adult↗
PubMed2001

The content of glycogen phosphorylase and glycogen in preparations of sarcoplasmic reticulum-glycogenolytic complex is enhanced in diabetic rat skeletal muscle.

AIMS/HYPOTHESIS: We have examined the effect of diabetes and pharmacological insulin treatment on the content of glycogen phosphorylase and glycogen associated with the sarcoplasmic reticulum-glycogenolytic complex from rat skeletal muscle. METHODS: Diabetes was induced in rats by streptozotocin injection. Enzymatic activities were measured using spectrophotometric methods. Glycogen phosphorylase was determined measuring the pyridoxal-5' -phosphate content and using polyacrylamide gel electrophoresis. Glycogen content was measured by enzymatic and the phenol sulfuric methods. RESULTS: The content of glycogen phosphorylase associated with the sarcoplasmic reticulum glycogenolytic complex gradually arises after diabetes induction. The content of glycogen phosphorylase was restored to a control value by pharmacological insulin treatment. In addition, the content of glycogen in preparations of sarcoplasmic reticulum-glycogenolytic complex of diabetic animals was also increased, whereas the content of glycogen in total muscle of diabetic rats was similar to that of the control rats. The absolute and relative amount of glycogen associated with sarcoplasmic reticulum seemed to increase in diabetic animals. These effects on the compartmentalisation of glycogen were suppressed by insulin treatment. Additionally, the rate of conversion of glycogen phosphorylase b to a, an index of the phosphorylase kinase activity, was 50 % lower in diabetic rats, increasing the dephosphorylated form of glycogen phosphorylase and, as a consequence, its association with sarcoplasmic reticulum membranes. CONCLUSION/INTERPRETATION: These results suggest that under diabetic conditions, both glycogen phosphorylase and a small percentage of muscle glycogen are relocalized in the sarcoplasmic reticulum-glycogenolytic complex.

Animals↗
PubMed2000

Disruption of spatial organization and interjoint coordination in Parkinson's disease, progressive supranuclear palsy, and multiple system atrophy.

Patients with basal ganglia diseases may exhibit ideomotor apraxia. To define the nature of the impairment of the action production system, we studied a repetitive gesture of slicing bread by three-dimensional computergraphic analysis in eight nondemented patients with Parkinson's disease in the "on" state, five with progressive supranuclear palsy and four with multiple system atrophy. Two patients with Parkinson's disease and two with progressive supranuclear palsy showed ideomotor apraxia for transitive movements on standard testing. A Selspott II system was used for kinematic analysis of wrist trajectories and angular motions of the shoulder and elbow joints. Patients with Parkinson's disease, progressive supranuclear palsy, and even some with multiple system atrophy exhibited kinematic deficits in the spatial precision of movement and velocity-curvature relationships; in addition, they failed to maintain proper angle/angle relationships and to apportion their relative joint amplitudes normally. Spatial disruption of wrist trajectories was more severe in patients with ideomotor apraxia. We posit that the basal ganglia are part of the parallel parieto-frontal circuits devoted to sensorimotor integration for object-oriented behavior. The severity and characteristics of spatial abnormalities of a transitive movement would therefore depend on the location and distribution of the pathologic process within these circuits.

Aged↗
PubMed1995

Interaction between glycogen phosphorylase and sarcoplasmic reticulum membranes and its functional implications.

Skeletal muscle glycogen phosphorylase b binds to sarcoplasmic reticulum (SR) membranes with a dissociation constant of 1.7 +/- 0.6 mg of phosphorylase/ml at 25 degrees C at physiological pH and ionic strength. Raising the temperature to 37 degrees C produced a 2-3-fold decrease in the dissociation constant. The SR membranes could bind up to 1.1 +/- 0.1 mg of glycogen phosphorylase b/mg of SR protein, whereas liposomes prepared with endogenous SR lipids and reconstituted Ca(2+)-ATPase were unable to bind glycogen phosphorylase. Binding of glycogen phosphorylase b to SR membranes is accompanied by inhibition of its activity in the presence of AMP. The Vmax for glycogen phosphorylase b associated with SR membranes is 40 +/- 5% of that for purified glycogen phosphorylase and shows a decreased affinity for its allosteric activators, AMP and IMP. These kinetic effects are also observed with purified glycogen phosphorylase b when starch or alpha-amylose is used as substrate instead of glycogen. Treatment of SR membranes with alpha-amylase produced dissociation of glycogen phosphorylase b from the SR membranes. Thus, linear polysaccharide fragments of glycogen bound to the SR membranes are likely mediating the binding of glycogen phosphorylase b to these membranes.

Animals↗
PubMed1994

Quantification and removal of glycogen phosphorylase and other enzymes associated with sarcoplasmic reticulum membrane preparations.

The enzymatic characterization of sarcoplasmic reticulum membrane fragments from rabbit skeletal muscle presented in this paper shows that glycogen phosphorylase, as well as other enzymes (e.g., creatine kinase, myokinase, phosphorylase kinase, glycosidase, AMP-deaminase, phosphoglucomutase) are associated with these membrane preparations. Amongst these enzymes, the highest activity associated with sarcoplasmic reticulum membranes is that of glycogen phosphorylase, which is mostly (at least 95%) in its b form (dephosphorylated form), since its activity in sarcoplasmic reticulum membranes is largely dependent upon AMP. A protocol is presented to quantify the amount of phosphorylase bound to sarcoplasmic reticulum membranes from fluorimetric measurements of the content of its coenzyme, pyridoxal 5'-phosphate. The content of phosphorylase ranged from 0.03 to 0.37 mg phosphorylase per mg of membrane protein, in sarcoplasmic reticulum membrane preparations made following several of the protocols most commonly used and also depending upon the length of the starvation period of the animal before killing. We also show that dilution of sarcoplasmic reticulum membranes to 0.1-0.2 mg protein per ml in a buffer containing 50 mM Tes-KOH (pH 7.4), 0.1 M KCl and 0.25 M sucrose removes at least 95% of glycogen phosphorylase from these membrane fragments, as well as other enzymes like myokinase and glycosidase. On these grounds, we suggest to introduce a final dilution step as indicated above in protocols of sarcoplasmic reticulum membrane preparations.

AMP Deaminase↗
PubMed1993

Glycogen phosphorolysis can form a metabolic shuttle to support Ca2+ uptake by sarcoplasmic reticulum membranes in skeletal muscle.

In the presence of glycogen, ADP, phosphoglucomutase and hexokinase, the glycogen phosphorylase b activity associated to sarcoplasmic reticulum (SR) membranes stimulates Ca2+ uptake by SR membrane fragments in the absence of added ATP. Phosphoglucomutase and hexokinase lead to the formation of glucose 6-phosphate which in turn is used as an ATP regenerating system by the Ca2+ pump. It is proposed that a raise of cytosolic AMP and ADP concentrations after muscle contraction can activate an alternative metabolic route which would be used to ensure the maintenance of a low cytosolic Ca2+ concentration and avoid unnecessary metabolic energy depletion in muscle cells.

Adenosine Monophosphate↗
PubMed1993

Abnormal sympathetic skin response in patients with autoimmune vitiligo and primary autoimmune hypothyroidism.

The sympathetic skin response was studied in 21 patients with autoimmune vitiligo or hypothyroidism or both. No response to stimulation was found in 6 patients, but 4 with both diseases showed abnormal results. Sympathetic skin response is useful in evaluating sudomotor activity of the autonomic nervous system, and it is concluded that patients with autoimmune vitiligo, autoimmune hypothyroidism and especially those with both diseases show evidence of sudomotor dysfunction.

Autoimmune Diseases↗
PubMed1993

[Spinal arachnoiditis as a complication of peridural anesthesia].

Seven patients who received epidural anesthesia for gynecological (5 cases), cosmetic (1 case) or general surgery (1 case) developed spinal arachnoiditis leading to subarachnoid cyst in all 7 and cord cavitation in 5. MRI was useful to show the subarachnoid and intramedullary cysts, as well as to monitor lesion extent and progress. Associated MRI findings were a Chiari anomaly in one case, a tethered cord in another and spinal cord atrophy in a third. One patient refused surgery but improved spontaneously while the other six were treated by a shunting procedure, with a satisfactory outcome in three. Meningeal inflammation may have left scars which later induced ischemia and subsequent cavitation. Alternatively, CSF circulation blockade may have dilated the central spinal canal causing ischemia by compression, followed by myelomalacia and cavitation. Careful handling of this procedure is urged in order to avoid such severe complications.

Adolescent↗
PubMed1990

Acute CNS infection by Trypanosoma cruzi (Chagas' disease) in immunosuppressed patients.

Acute CNS involvement by Trypanosoma cruzi is uncommon. We report 2 immunosuppressed patients, 1 adult who developed an acute meningoencephalitis, and 1 child who presented with the tumor-like form of the disease. Both patients acquired the disease through blood transfusion. Blood donors migrating from endemic areas can transmit the disease in nonendemic countries if they are not routinely screened for antibodies to T cruzi.

Acute Disease↗
PubMed1988

Unusual manifestations of basilar artery ectasia.

Three patients with unusual presentations of basilar artery ectasia are described: subarachnoid hemorrhage was manifest in one and autonomic dysfunction developed in the other two. Aneurysmal rupture was the cause in the first patient, while compression of the brainstem and/or of the baroreceptor afferences of the IXth and Xth cranial nerves is postulated to be responsible for the symptoms found in the other two. Basilar artery aneurysms should be considered in cases with subarachnoid hemorrhage or autonomic dysfunction, particularly when diagnostic procedures fail to disclose other possible etiologies.

Autonomic Nervous System Diseases↗
PubMed1982

Tizanidine in the treatment of spasticity.

A double-blind crossover trial compared tizanidine with baclofen in 36 patients with spasticity. Tizanidine appeared to reduce lower limb spasticity more effectively and to have fewer side effects, but no statistically significant differences emerged when the two drugs were compared. An additional open study of tizanidine confirmed the beneficial action in a selected minority of patients with spasticity. This drug may have an important role in the management of spasticity, but further studies are required.

Adult↗
PubMedDate not supplied

Ca2+ uptake coupled to glycogen phosphorolysis in the glycogenolytic-sarcoplasmic reticulum complex from rat skeletal muscle.

The glycogenolytic-sarcoplasmic reticulum complex from rat skeletal muscle accumulates Ca2+ upon stimulation of glycogen phosphorolysis in the absence of added ATP. It is shown that an efficient Ca2+ uptake involves the sequential action of glycogen phosphorylase, phosphoglucomutase and hexokinase, which generate low concentrations of ATP (approximately 1-2 microM) compartmentalized in the immediate vicinity of the sarcoplasmic reticulum Ca2+, Mg(2+)-ATPase (the Ca2+ pump). The Ca2+ uptake supported by glycogenolysis in this subcellular structure is strongly stimulated by micromolar concentrations of AMP, showing that the glycogen phosphorylase associated with this complex is in the dephosphorylated b form. The results point out that the flux through this compartmentalized metabolic pathway should be enhanced in physiological conditions leading to increased AMP concentrations in the sarcoplasm, such as long-lasting contractions and in ischemic muscle.

Adenosine Monophosphate↗