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P Collin

Publications and source records attributed to P Collin.

106 records · Page 6Linked to original sources
PubMed1989

Microcinematographic and autoradiographic kinetic studies of bone cell differentiation in vitro: matrix formation and mineralization.

Matrix formation and mineralization have been reported in vitro with cells isolated from rat calvaria bones by collagenase digestion (Nefussi et al., 1985). In the current study, kinetics of bone nodule formation and osteoblastic cell differentiation were studied in this in vitro system using an improved microcinematographic device and flash and follow-up labeling autoradiographic techniques. Microcinematographic analysis showed the formation of bone nodules within 24 h. The initial event observed was the change in the top cells layer which became alkaline phosphatase positive. Matrix synthesis occurred a few hours after this. The autoradiographic results demonstrated the formation of an integrated system where osteoblasts and osteocytes were active and synthesized a collagen matrix and mineralized it in a similar time sequence than in vivo.

Alkaline Phosphatase↗
PubMed1989

High frequency of coeliac disease in adult patients with type-I diabetes.

Anti-reticulin antibodies were measured by an indirect immunofluorescence method in 195 consecutive patients with insulin-dependent diabetes mellitus, and positive titres were found in 8 patients. A jejunal biopsy was performed in these patients, all of whom had small-intestinal atrophy. Thus the frequency of coeliac disease in adult diabetes patients was 4.1%. The patients had no signs of malabsorption or of significant abdominal complaints. We conclude that coeliac disease is commoner in type-I diabetes than in the normal population, and measurement of anti-reticulin antibodies seems to be a suitable screening method.

Adolescent↗
PubMed1989

Effects of keto-analogues on phosphocalcic and aminoacid metabolism in dialysed patients: a crossover study.

It has been suggested that calcium salts of keto-analogues (KA) have beneficial effects on phosphocalcic and aminoacid (AA) metabolism. To confirm this, their short-term effects were evaluated on chronic dialyzed patients. In a prospective, randomised, crossover study, eight and seven patients were put on KA (200 mg/kg/d) and assigned either a low-protein diet (LP:0.4 g/kg/d) or a normal one (NP: 1 g/kg/d) for 15 days. The two treatments were interchanged after 15 days of washout. KA.LP was accompanied by: a) decreases in calorie intake (12%; p = 0.001) and in blood concentrations of albumin (5%, p = 0.004), urea (32%, p = 0.001), phosphate (29%, p = 0.001), parathormone (27%, p = 0.008), isoleucine (24%, p = 0.04), 1 and 3 methyl-histidine (71%, p = 0.03; 24%, p = 0.005), valine (19%, p = 0.004) and hydroxyproline (85%, p = 0.009); b) increases in calcemia (9%, p = 0.002), cystathionine (991%, p = 0.0001) and threonine (22%, p = 0.04). KA.NP was accompanied by: a) decreases in phosphatemia (15%, p = 0.03) and parathormone (18%, p = 0.06); b) increases in calcemia (9%, p = 0.002), cystathionine (427%, p = 0.0001), and phenylalanine (28%, p = 0.013). Calcium salts of keto-analogues together with a low or normal protein diet thus seem to reduce blood concentrations of phosphates and parathormone, and raise calcium; however their action on aminoacids needs further investigation.

Aged↗
PubMed1988

[Effects of keto-analogs of essential amino acids with or without associated protein restriction on the phospho-calcium metabolism of hemodialysed patients: a randomized prospective crossover study].

The short term effects of a low (RP: 0.4 g/kg/day) and a normal (RN: 1 g/kg/day) protein diet supplemented by calcium salts of keto-analogs (CA) (200 mg/kg/day) were observed in a crossover study of phosphocalcic metabolism in 15 chronic dialysed patients during 15 days using a crossover device. CA were well tolerated but CA.RP was accompanied by a caloric diminution of 12% (p = 0.001) and albumin reduction of 5% (p = 0.004). Blood urea nitrogen was reduced by 32% (p = 0.001) with CA.RP. Blood creatinine was not modified by CA.RP or CA. RN. Blood phosphorus (P) and parathormone (PTH) levels were respectively reduced by 29% (p = 0.001) and 27% (p = 0.008) with CA.RP; and by 15% (p = 0.03) and 18% (p = 0.006) with CA.RN. Calcemia was raised about 9% (p = 0.002) by both sets of treatment. There was no significant difference between the two treatments. Thus CA can reduce P and PTH without need for a restricted protein diet which may be accompanied by complications on long term utilisation.

Amino Acids↗
PubMed1986

Avidity of antigliadin IgA and IgG antibodies in gluten-sensitive enteropathy and dermatitis herpetiformis.

Antigliadin antibodies (AGA) of IgG and IgA class were assayed with a modified enzymeimmunoassay in serum samples of 18 patients with gluten-sensitive enteropathy and 30 patients with dermatitis herpetiformis. No difference between antibody amount or avidity of the two groups of patients was observed. Avidity and total amount of AGA were also compared in 15 patients with a recent diagnosis of dermatitis herpetiformis and in 15 patients with a disease history of several years without a proper gluten-free diet. No difference in IgG antibodies was found but the amount of high avidity IgA antibodies was significantly higher in patients with several years' experience of dermatitis herpetiformis than in those with a recent diagnosis. The results indicate that in dermatitis herpetiformis, maturation of IgA response occurs. Further, clinically, maturation of anti-gliadin IgA response during the disease can increase the sensitivity of the patient against diet-derived gliadin.

Antibody Affinity↗
PubMed1986

[Surgery of acquired heart valve diseases in France: developments in a 10-year period. A multicentric study].

A multicenter study compares the surgery of acquired valvular diseases in France in 1974 and 1984. This study concerns etiology, surgical procedures and postoperative results within 3 months after operation. 2718 observations issued from 20 medical and surgical centers are divided in 2 groups: the first includes 856 patients who underwent surgical operation in 1974, the other group with 1862 patients was operated on in 1984. Significant differences may be observed. The mean age is higher in 1984 (55 vs. 47 years); the rheumatismal etiology decreases from 50.2% in 1974 to 35.1% in 1984; the degenerative and dystrophic causes increase from 13.8% in 1974 to 32.9% in 1984; while the monovalvular mitral lesion is more frequent (42%) than the aortic one (32.7%) in 1974, the proportion is reversed in 1984 where 47% aortic and 34.5% mitral lesions are found; the number of surgical treatments of mitral stenoses in 1984 is half of those in 1974, but the number of surgically treated aortic stenoses and mitral regurgitations is double of those in 1974; the preoperative examination includes left-side heart catheterization in 81.1% and coronary angiography in 64% of surgically treated patients en 1984, the respective percentages en 1974 being 57.8% and 16.1%. In 1974, 27.6% of patients are in a preoperative functional stage I or II, in contrast to 42.8% in 1984. Mitral commissurotomy represents 29.3% of mitral surgery in 1974 (25.6% of them with closed operation), the respective percentage in 1984 being only 10.5% (2.5% of them with closed heart operation).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

Insulin binding to plastic bags: a methodologic study.

A radiotracer method to assess insulin binding to commercially available plastic peritoneal dialysis solution containers was developed. A peritoneal dialysis bag (bag 2) was emptied and attached to another full bag (bag 1) of the same kind. In the syringe-to-bag method, bag 1 was symmetrically injected through the bag wall with four syringes containing dialysis solution and radioactive insulin, with or without regular insulin. The radioactivity in each syringe was measured with a gamma counter before injection, and all of the samples were counted afterwards directly in the syringes. Using a bag-to-bag transfer method, bag 1 was agitated, eight samples were taken from different parts through the wall, and then the contents were transferred to bag 2. Bag 2 was then agitated and eight samples were taken and counted. In the bag-pieces method, pieces of bag wall were cut and the radioactivity on the walls was measured to determine the amount of binding. The syringe-to-bag method gave negative results, severely underestimating the amount of insulin binding. The bag-to-bag transfer method yielded positive results in all instances. Increasing the amounts of regular insulin had no demonstrable impact on percent of binding. When the bag-to-bag method was compared with the bag-pieces method, it gave only slightly higher values; however, the bag-to-bag method was considered more reliable because the counting can be controlled more effectively. A 15-minute delay in sampling was not found to influence insulin binding. A reliable method of assessing insulin binding must be based on the following two principles: (1) The transfer of samples to intermediate containers should be avoided, and (2) radiotracer concentrations in the samples should be similar.

Dialysis↗
PubMed1976

Progressive muscular dystrophy. Functional improvement after a renal allograft.

From his first years a child showed signs of a primary and rapidly developing muscular dystrophy. The diagnosis was established by an increased serum CK level and by electromyography and muscle biopsies. Afterwards this child developed a severe renal deficiency which needed binephrectomy and the graft of a normal kidney. During the few months just after the graft, the disability increased and the patient could not stand upright by himself. Later on, he gradually became able to walk on his own and without bracing. He could climb stairs and stand up from the floor. The CK activity returned to normal. At present, 4 years after the graft (the patient is 16 years), the improvement of his functional abilities is constant, although the CK activity has increased again. In this article we give evidence that this patient suffers from a primary muscular dystrophy. We discuss the type of dystrophy concerned. We believe that it is the graft of a normal kidney which was responsible for the improvement observed, and not the physiotherapy or the drugs administered after the graft.

Adolescent↗
PubMedDate not supplied

Antibodies in relation to gluten intake.

Serum reticulin, endomysial and gliadin antibody tests are used in serological screening and case finding of coeliac disease, as well as the novel tissue transglutaminase antibody test. None of these tests are 100% predictive, however. Reticulin/endomysial antibodies predict forthcoming coeliac disease in individuals with normal small-bowel mucosal morphology. The effect of a gluten-free diet can be monitored with serological tests. A positive test result often indicates an inadequate gluten-free diet. However, slight dietary transgressions and minor mucosal damages cannot always be revealed with the serological tests. Therefore, small-bowel mucosal biopsy remains the most sensitive method to monitor the effect of a gluten-free diet.

Autoantibodies↗