PubMed Health⌕ Search

Biomedical subjects

P Mathieu

Publications and source records attributed to P Mathieu.

At least 91 records · Page 5Linked to original sources

[Rate of joint space pinching in coxarthrosis].

Accurate measures of cartilage destruction are needed to evaluate the effects of chondroprotective agents in human osteoarthritis. Use of a digitalized image analyzer (HOLOGIC, ICMS software) to measure mean joint space width on roentgenograms of the hip is a simple, reliable method with a coefficient of variation of 3.3%. To determine the rate of joint space loss and to identify factors associated with this parameter, we retrospectively studied 56 hips with osteoarthritis in 39 patients (mean age at baseline 55.5 +/- 12 years; mean roentgenographic follow-up 5.2 +/- 3.6 years, mean number of roentgenograms per patient 3.7 +/- 1.1). Mean annual joint space loss was 13.5 +/- 16.6%, i.e., 0.42 +/- 0.38 mm, and was negatively correlated with the duration of roentgenographic follow-up (r = 0.95 and 0.97, p < 0.01). When only those subjects who were followed up for two to eight years were studied, mean joint space loss was only 6.7% with a considerably smaller standard deviation of 4.2%, i.e., 0.29 +/- 0.21 mm. No influence on the rate of joint space loss was found for age at onset of symptoms, age at the first roentgenographic study, side, gender, or location of the joint space narrowing. The roentgenographic stage or joint space width at baseline were positively correlated with the rate of joint space loss expressed as a percentage but not in mm. These data suggest that the absolute amount of cartilage lost is not influenced by the roentgenographic stage of the osteoarthritis at inclusion of the patient in the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Serum parathormone profile during surgical treatment of hyperfunctioning parathyroid adenoma: a multicompartmental model.

Patterns of intact parathyroid hormone (iPTH) elimination and subsequent recovery of parathyroid function were studied in seven patients undergoing surgical removal of solitary hyperfunctioning parathyroid adenoma. Using a sensitive two-site immunoradiometric assay, iPTH levels were measured pre, peri-, and postoperatively. Blood samples were taken at very early and at late stages, including 3, 6, 9, and 15 minutes and 48, 72, and 96 h after adenomectomy. A biexponential formula was calculated to fit the decreasing values of iPTH in all patients. The PTH half-life in the early phase was 1.4 +/- 1.1 minutes (95% confidence limits). The PTH half-life in the second phase was 64.45 +/- 32.19 minutes (95% confidence limits). A third phase is represented by a slow, linear increase in plasma iPTH values as a result of the recovery of healthy suppressed parathyroid glands. The extrapolation to baseline of the later phase shows that the recovery of normal parathyroid function begins as soon as 240 minutes after adenomectomy and is independent of the decrease in PTH of adenomatous origin. All individual results were consistent with this model. Five patients had iPTH values below 5 pg/ml, one had 15 pg/ml, and the last had 27 pg/ml 5 h after parathyroid adenomectomy. The recovery of the hormonal activity of the remaining glands occurred rapidly. By the postoperative hour 24 the mean serum iPTH concentration was 12.28 +/- 8.07 pg/ml. The intraoperative serum iPTH concentration offers a model to assess both recovery of hormonal secretion from functionally suppressed parathyroid glands and disappearance of parathyroid hormone.

Adenoma↗

[Serum phospholipase A2 activity in osteoarthritis].

Serum phospholipase A2 activity in 67 osteoarthritis patients and 17 controls was determined using a radiolabeled specific substrate. Serum phospholipase A2 activity was significantly higher in osteoarthritis patients (115 +/- 73.6 dpm/h/ml) than in controls (45 +/- 25 dpm/h/ml) (p = 0.002). In 41 osteoarthritis patients, serum phospholipase A2 activity was unrelated to age, time since onset of osteoarthritis symptoms, duration of morning stiffness, Lequesne's index, roentgenographic stage of osteoarthritis, number of joints with osteoarthritis, erythrocyte sedimentation rate, or serum C-reactive protein levels. In 12 osteoarthritis patients who were evaluated twice at a mean interval of 46 days, changes in serum phospholipase A2 activity were unrelated to changes in Lequesne's index. Blind evaluation of long-term joint space loss was performed in 14 patients; serum phospholipase A2 activity increased only in those patients with progressive joint space loss, but the difference was not statistically significant as compared with the controls. These data suggest that serum phospholipase A2 activity is not useful in practice as a marker for osteoarthritis.

Adult↗

[Recommended methods for the determination of catecholamines and their metabolites in urine. Significance of results in the diagnosis and follow-up of pheochromocytoma and neuroblastoma].

Laboratory investigation of catecholamines is useful for the clinician in the diagnosis and management of phaeochromocytoma and neuroblastoma. This work summarizes current knowledge on catecholamines and their metabolites and discusses the main indications for their determination. It also examines the most practical methods for studying the secretion of these hormones, ie extraction, separation and quantification using high performance liquid chromatography coupled with electrochemical detection. The workshops attended by the members of the catecholamines working party of the French Clinical Biology Society and phaeochromocytoma and neuroblastoma specialists enabled the role of such determinations in the diagnosis and management of these diseases to be clarified.

Adolescent↗

Metalloprotease activity, phospholipase A2 activity and cytokine concentration in osteoarthritis synovial fluids.

Collagenase, stromelysin and phospholipase A2 (PLA2) activity as well as interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF alpha) and interleukin 6 (IL-6) concentration were determined in the knee joint synovial fluid (SF) of 26 patients with osteoarthritis (OA) and with rheumatoid arthritis (RA). Collagenase and stromelysin were detected in 80.7 and 69.2% of OA SF, respectively. When present, the mean activity of both enzymes was approximately two times lower in OA than in RA SF. PLA2 activity was present in all SF with no significant difference between OA and RA SF. IL-1 beta, TNF alpha and IL-6 were found in 0, 96.1 and 84.6% of OA SF, respectively. Mean TNF alpha and IL-6 concentration was also lower in OA than in RA SF. Metalloprotease activity correlated weakly with IL-6 level and enzymatic activities were unrelated with TNF alpha in OA SF.

Adult↗

[Measurement of the hip joint space using automatic digital image analysis].

Joint surface area (JSA) and mean joint space width (MJSW) at the hip were measured using a ICMS-Techline computer program to analyze digitalised frontal weight-bearing roentgenograms of the pelvis. With this technique, the portion of joint space studied is always the same in a given patient and is enclosed within an acute ECS angle whose apex C is the center of the head of the femur and whose ends E and S are the lateral rim of the acetabulum and the highest point of the homolateral sacral wing respectively. ECS varies across individuals but remains constant in a given hip. Twenty hips were included in the first part of the study. For each hip, three roentgenograms were taken at five-minute intervals by three different radiologists who used their own constants (settings, position of the subject). JSA and MJSW are determined five times on each film by two different observers who had no information on the films under study. The interobserver coefficient of variation (CV) was 4.7% for JSA and 3.3% for MJSW. Intra-observer CVs were 2.97 and 3.54% for MJSW and 4.32% and 5.13% for JSA. There was a very close correlation between MJSW and JSA (r = 0.87, p < 0.0001). MJSW was then determined for roentgenograms of 30 hips with osteoarthritis. Results were compared with the values obtained using Lequesne's method of joint space measurement at the site of maximum narrowing. Measurements were performed in a double-blind fashion by two observers. The correlation coefficient was r = 0.89 (p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Neuroblastoma in children: clinical and biological aspects. An experience of screening in France].

Neuroblastoma is the commonest solid tumour in children under the age of 5 years (50% of cases before 2 years, 90% before 5) and the second cause of death after accidents. Approximately one child in 10,000 develops neuroblastoma by the age of 15 years. The situation in other European and North American countries is similar to that in France. As neuroblastoma is derived from the sympathetic nervous tissues, it is associated with the production of large amounts of catecholamines and their metabolites which are excreted in the urine. Less than 5% of cases do not produce catecholamines. Vanillylmandelic acid (VMA), homovanillic acid (HVA) and dopamine (DA) are the most useful chemical markers for the diagnosis and clinical control of neuroblastoma. They are generally measured using the reliable and sensitive high pressure liquid chromatography (HPLC). Survival is related to stage (the Evan's staging protocol has been superseded by the INNS staging), and age at diagnosis. There is almost 100% survival for stages I and IIa before the age of 12 months, and less than 20% for stage IV when diagnosed after 2 years of age. Multiple copies of the N-myc oncogene, deletions of chromosome 1p, and diploidy in tumour cells are associated with poor prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Serum hyaluronic acid in osteoarthritis].

In this prospective study, serum hyaluronate (SH) was assayed using a radiometric method (Pharmacia) in 73 osteoarthritis patients and 39 controls. All assays were performed between 8 h 00 and 9 h 00 a.m. because SH levels exhibit circadian variations. SH levels were significantly higher in patients with osteoarthritis than in controls (92 +/- 66 micrograms/l and 39 +/- 21 micrograms/l, respectively, p = 0.0001). Among 50 patients with osteoarthritis, including 29 with knee involvement and 21 with hip involvement, SH levels were not correlated with morning stiffness, duration of symptoms, Lequesne's algofunctional index, erythrocyte sedimentation rate, C-reactive protein, severity of roentgenographic changes in the affected knee or hip, disease extension, or severity. The lack of any relationship between changes in SH levels and Lequesne's is index values in 25 patients or between SH levels and joint space narrowing evaluated retrospectively in 16 patients, as well as the prompt return to high SH levels after arthroplasty and synovectomy in 14 patients with hip joint osteoarthritis, suggest that this potential marker is not useful for monitoring osteoarthritis in a single joint.

Adult↗