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C Massoubre

Publications and source records attributed to C Massoubre.

15 recordsLinked to original sources
PubMed2000

Mineralization and alkaline phosphatase activity in collagen lattices populated by human osteoblasts.

Adult human osteoblastic cells were grown in a native type I collagen gel. Proliferation and viability analyses showed that cells rapidly stopped dividing and became blocked in the G0G1 phase (91% on day 13). Carboxyfluorescein diacetate cell staining and flow cytometry showed that osteoblasts were viable for the first 16 days and then viability decreased (58% viable cells on day 22). Osteoblasts were able to retract the matrix. Betaglycerophosphate (betaGP) stimulated the deposition of mineral particles in the collagen network, and electron probe microanalysis showed that they were principally calcium and phosphorus, with a Ca/P ratio of about 1.7. Various times of betaGP supply were tested. We compared 10 mM betaGP added only once at day 0, or continuously from day 0, day 8, or day 21. Mineralization was observed in conditions where betaGP was added at day 0. Furthermore, 10 mM betaGP added once during gel preparation was sufficient to induce mineralization with mineral accumulation up to day 15 whereas the speed of the gel contraction decreased. In every condition, cultures expressed high alkaline phosphatase (ALP) levels as early as day 3, which decreased afterwards. These kinetics might explain why the other conditions did not prove favorable to the mineralization process. The model was used to study the influence of blocking gel retraction. Blocking retraction delayed the ALP activity decrease, but had no effect on mineralization. In conclusion, human adult osteoblasts cultured in native collagen gel stopped proliferation and underwent mineralization very early. This model should be used to investigate the influence of effectors on the early stages of culture.

Aged↗
PubMed1993

Human neutrophil gelatinase is a collagenase type IV.

Secreted gelatinase from human neutrophils was purified as a 94 kDa polypeptide. Gelatinolytic and type IV collagenolytic activities of the purified protein were measured and compared. Immunoglobulins purified from antisera raised against gelatinase inhibited both the gelatinase and type IV collagenase activities. There was no cross-reaction in the inhibition with type I collagenase while the three metalloproteases were similarly inhibited by recombinant tissue inhibitor of metalloproteases. Purified gelatinase degraded denatured type I and native type IV collagens; there was no proteolysis of native type I collagen.

Collagenases↗
PubMed1992

[Serum myoglobin: evaluation of two immunolatex methods. Comparison with a radioimmunoassay method].

Latex immunoturbidimetric (ITA) and immunonephelemetric (INA) assays, were evaluated and compared to a radioimmunological assay (RIA) for the determination of serum myoglobin. Within-run and between-run assays and accuracy and linearity studies gave satisfactory results, very similar to those of RIA. Results were closely correlated with those of RIA for 100 samples of up to 2,000 micrograms/l (correlation coefficients respectively 0.96 and 0.97 for ITA and INA). Reference values (150 men and 150 women; range 20-65 years) were determined and expressed in percentiles. It is concluded that the two latex immunologic assays facilitate laboratory myoglobin evaluation (no radioactive material, short performance time). ITA is more suitable for emergency analysis and INA is more convenient for serial analysis and particular samples (presence of hemoglobin or chylomicrons).

Adult↗
PubMed1992

Simple and sensitive determination of urea in serum and urine.

In this method for serum and urinary urea determination, the same reagent is used without predilution of urine samples. The method is based on the pH increase resulting from the ammonia released by urease hydrolysis of urea. o-Cresolphthalein complexone is used to monitor the pH change colorimetrically. Urea concentration and absorbance at 570 nm are linearly related for concentrations as great as 600 mmol/L for urine samples and 100 mmol/L for serum. There are no clinically significant interferences from physiological substances or drugs, and precision and accuracy are excellent (CV approximately 2%, except at very low concentrations in serum; analytical recovery was 99% in urine, 100% in serum). Results by this method (y) and by the Astra method (x) for urine correlated well (y = 0.991x - 2.87, Sy/x = 9.21, r = 0.994), as did the results by this method and by the total enzymatic method (x') for serum (y = 1.002x' + 0.192, Sy/x' = 0.598, r = 0.997). This method is applicable to automated as well as manual instruments, and one-reagent or two-reagent formats can be used.

Ammonia↗
PubMed1989

An improved pyrogallol red-molybdate method for determining total urinary protein.

We adapted the pyrogallol red-molybdate method for total urinary protein to the Cobas Bio centrifugal analyzer. The method is simple, rapid, sensitive, and inexpensive. Addition of 25 mg of sodium dodecyl sulfate per liter to the reagent modifies protein reactivities so that the chromogenicity of human gamma globulins is the same as that of albumin. Results by this method and a comparison method that included gel filtration and a modified biuret reaction correlated well (r = 0.951).

Adult↗
PubMed1989

[Microalbuminuria: evaluation of an immunoturbidimetric method and an immunonephelemetric method].

Two methods for measurement microalbuminuria are appraised to take the place of RIA. One is immunonephelemetry, using a "closed" immunochemistry analyzer of modest price. The other one is immunoturbidimetry on an "open" centrifugal analyzer, which is of a middle price. The results which are obtained by IN and IT are compared statistically to the RIA. These methods give satisfaction for practicability, precision and accuracy and can be used in any biological laboratory.

Albuminuria↗
PubMedDate not supplied

Characterization of human osteoblastic cells: influence of the culture conditions.

Human osteoblastic cells were isolated enzymatically from adult human spongy bone and grown in MEM-Ham F12 1:1 medium supplemented with 2% Ultroser (USM). They were subcultured and examined for osteoblast features by morphological, histological, and biochemical approaches. The cells had a characteristic polyhedral morphology and produced a high level of alkaline phosphatase (ALKP). Confluent cultures were uniformly stained for ALKP and flow cytometry analysis with fluorescein diphosphate gave a single peak signal, reflecting a highly positive population, distinct from cultures of fibroblasts. The ALKP activity was stimulated by 1,25 (OH)2 vitamin D3. CD 44 was strongly expressed in these cultures, although osteoblasts are negative in vivo and osteocytes are positive. The main collagen synthesized was type I collagen and osteocalcin was produced after stimulation by vitamin D3. 10 mM betaGP induced mineralization and microprobe analysis of the crystals showed a composition close to hydroxyapatite. Changing the culture conditions to MEM-10% calf serum acted on cell behavior: it reduced the production of these biochemical markers of osteoblasts and the morphology became fibroblastlike with more rapid cell multiplication. The parameter most affected by the change in culture medium was ALKP, which was selected as the determinant criterion for defining an osteoblast culture. ALKP activity was then used to characterize a culture of cells seeded in a collagen gel.

Adult↗
PubMedDate not supplied

[Atypical antipsychotics].

This paper synthetizes important information concerning principal atypical antipsychotic drugs actually used in clinical practice: classification, pharmacokinetics, therapeutic uses, side effects, contra-indications and drug interactions. These molecules have heterogeneous structures, but are more and more used because of good neurological tolerance, greater efficacy against negative symptoms, and for clozapin greater efficacy against resistant schizophrenia.

Antipsychotic Agents↗
PubMedDate not supplied

[Is cocoa a psychotropic drug? Psychopathologic study of a population of subjects self-identified as chocolate addicts].

The aim of this work was to search for eating disorders, DSM III-R Axis I mental disorders, personality disorders, and addictive behavior, in self-labeled "chocolate addicts". Subjects were recruited through advertisements placed in a university and a hospital. Fifteen subjects were included, 3 men and 12 women aged between 18 and 49. Most of them were not overweight, although 7 thought they had a weight problem. They consumed an average of 50 g per day of pure cacao and, for 13 subjects, this consumption was lasting since childhood or adolescence. The psychological effects of chocolate, as indicated by the subjects, consisted in feelings of increased energy or increased concentration ability, and in an anxiolytic effect during stress. Seven subjects described minor withdrawal symptoms. None of the subjects reached the thresholds for eating disorders on the EAT and BULIT scales. The structured interview (MINI) identified an important ratio of subjects with a history of major depressive episode (13/15), and one woman was currently experiencing a major depressive episode. Four people suffered, or had suffered from anxiety disorders. Although only one subject satisfied all criteria for a personality disorder on the DIP-Q, seven displayed some pathological personality features. The self-labeled "chocoholics" do not seem to suffer from eating disorders, but may represent a population of psychologically vulnerable and depression--or anxiety--prone people. They seem to use chocolate as a light psychotropic drug able to relieve some of their distress. The amount of cacao consumed, although very chronically, remains moderate, and they rarely display other addictive behaviors.

Adolescent↗
PubMedDate not supplied

[Baker and Itagliata's Quality of Life Scale in a group of 139 schizophrenic patients: factorial analysis and evaluation of global validity].

The Satisfaction with Life Domains Scale SLDS published by Baker and Intagliata in 1982 and translated in French by Chambon and al. is one of the most used rating scales in the field of Subjective Quality of Life (SQL) for patients suffering from schizophrenia. It comprises 16 scales in 7 points and Likert format exploring the following fields: home/apartment/place of residence, neighbourhood, food, clothes, health, people they live with, friends, love life, relationships with their family, how they get on with other people, job/work day programming, spare time, what they do in the community for fun, services and facilities in their area, economic situation, general quality of life. In this study we present results on SLDS about 139 schizophrenic patients (108 males, 31 females) recruited in two centers Lyon (n = 41) and Saint-Etienne (n = 98). The SLDS was a part of more comprehensive studies including evaluation of needs for care, social support, delivery and costs of services. Diagnosis were confirmed using either the SCAN and CATEGO program (n = 108) or the list of the ICD-10 criteria (n = 31) applied at time of inclusion or on the basis of a representative episode of the illness. Patients were classified in two groups, the S group (S, n = 53) for those patients presenting clinical features at time of inclusion excepted residual forms (F 20.5) and the non S group (N-S, n = 86) for those patients free of symptoms at the time of assessment. Non parametric statistics (U test and Kendall test) were used for comparisons between groups. The field by field comparison of the scores shows the poorest level of SQL for love life (m = 4.2; sd = 1.8) and economic status (m = 4.4; sd = 1.8). Comparisons between S and non-S groups show an average range systematically higher for the non-S group and significant differences for the following fields: food, friends, how they get on with other people. The same comparisons between males and females show no significant differences excepted for the following fields: love life, economic situation. Principal components analysis with Varimax rotation were performed and a 4 factors solution was considered as the best one. Before rotation the first factor accounts for 31% of the variance and comprises all the items with loading higher than 0.4 allowing us to consider the possibility of a global score. This global score is normally distributed (m = 95.1 sd = 17.3) and shows a significant difference between S and non S-groups (S m = 92.2 sd = 20.1; non S m = 99.6 sd = 15.4 p = .02) but not between centers and between males and females. After rotation the first factor comprises relationships with family, how they get on with other people, job/work/day programming, spare time, what they do for fun and life in general. The hypothesis of unidimensionality of QV has to be tested using the RASCH model.

Adult↗