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E Legrand

Publications and source records attributed to E Legrand.

139 records · Page 8Linked to original sources
PubMedDate not supplied

Comparison of eight histomorphometric methods for measuring trabecular bone architecture by image analysis on histological sections.

Osteoporosis is defined as a disease characterized by low bone mass and microarchitectural deterioration of trabecular bone leading to enhanced bone fragility. Various histomorphometric methods have been described to measure bone architecture on histological sections. However, not all of the methods are strictly equivalent and some of them appear able to detect differences earlier in the course of the disease. We have compared 8 histomorphometric methods known to characterize the architecture of trabecular bone in 154 male osteoporotic patients. Measurements were done on transiliac bone biopsies: Trabecular number, thickness, and separation (Tb.N, Tb.Th, Tb.Sp); Trabecular Bone Pattern Factor (TBPf); Euler-Poincare's number (E); Interconnectivity Index (ICI); strut analysis of the trabecular network with the ratio of nodes/free-end (N/F); star volume of the bone marrow (V*m.space) and trabeculae (V*Tb) and the Kolmogorov fractal dimension of the trabecular boundaries (D). Relationships between the various architectural parameters were studied by hierarchical cluster analysis. Linear, hyperbolic, and exponential correlations were found between trabecular bone volume (BV/TV) and architectural parameters. Cluster analysis demonstrates the link between these architectural parameters. ICI, E, and TBPf, which reflect the amount of open/closed marrow cavities clustered together and appeared related to Tb.Sp, V*m.space which are indicators of the mean size of marrow cavities. Tb.Th, V*Tb and N/F flocked together as they reflect the trabecular size. Tb.N and D segregated together and seemed to best describe the trabecular network complexity. These histomorphometric techniques are correlated but correlations may be linear or nonlinear. Several histomorphometric techniques need to be used in parallel to appreciate the pathophysiological mechanisms of osteoporotic states.

Adult↗
PubMedDate not supplied

Thymic control in expression of natural killer activity in AKR and C57BL/6 mice.

The natural killer (NK) activity of 2-month old AKR mice was markedly depressed compared with that of C57BL/6 mice of the same age. It decreased with age in C57BL/6 mice, whereas it increased and reached a maximum at 5 months in AKR mice. When the animals developed leukaemia, NK activity completely disappeared. A considerable increase in NK activity was observed in AKR and C57BL/6 mice which had been thymectomized at 30 days of age. This activity remained at a high level for 3 months and slowly decreased afterwards. The NK activity of C57BL/6 mice fell after sublethal irradiation (1.75 Gy X 4) and did not recover within 12 weeks, except in mice restored with bone marrow (BM). When mice were thymectomized prior to radiation exposure, NK activity remained at a normal level and BM restoration resulted in a weak but significant enhancement. NK activity, which was already low in AKR mice, was not significantly modified by sublethal irradiation, whether the animals were previously thymectomized or not. In this strain, BM restoration increased the NK activity after sublethal irradiation, and a higher level was reached in thymectomized animals than in intact ones. Lethally irradiated mice restored with bone marrow displayed a high level of NK activity, which was comparable in both strains and was augmented by thymectomy. Taken together, these results indicate that spleen NK activity is, at least in part, controlled by the thymus. The increased NK activity in thymectomized animals might result from the decline or inactivation of a thymus-dependent suppressive activity. The low NK activity observed in AKR mice seems to be related to a thymus-mediated suppressive effect rather than to a defect of BM in NK precursors.

Age Factors↗
PubMedDate not supplied

Tuberculosis in the Caribbean: using spacer oligonucleotide typing to understand strain origin and transmission.

We used direct repeat (DR)-based spacer oligonucleotide typing (spoligotyping) (in association with double-repetitive element polymerase chain reaction, IS6110-restriction fragment length polymorphism [RFLP], and sometimes DR-RFLP and polymorphic GC-rich sequence-RFLP) to detect epidemiologic links and transmission patterns of Mycobacterium tuberculosis on Martinique, Guadeloupe, and French Guiana. In more than a third of the 218 strains we typed from this region, clusters and isolates shared genetic identity, which suggests epidemiologic links. However, because of limited epidemiologic information, only 14.2% of the strains could be directly linked. When spoligotyping patterns shared by two or more isolates were pooled with 392 spoligotypes from other parts of the world, new matches were detected, which suggests imported transmission. Persisting foci of endemic disease and increased active transmission due to high population flux and HIV-coinfection may be linked to the recent reemergence of tuberculosis in the Caribbean. We also found that several distinct families of spoligotypes are overrepresented in this region.

Bacterial Typing Techniques↗
PubMedDate not supplied

Subcutaneous abscess caused by Pleurophomopsis lignicola Petr: first case.

The dematiaceous coelomycete Pleurophomopsis lignicola Petr. was isolated repeatedly in pure culture from a subcutaneous abscess of the left leg in a farmer undergoing corticosteroid therapy for asthma gravis. To our knowledge, we report the first case involving this fungus as an aetiological agent of subcutaneous phaeohyphomycosis.

Abscess↗
PubMedDate not supplied

Inhospital management of common lumbosciatic syndrome. An opinion survey among French rheumatologists.

To determine which treatments are most commonly offered to patients younger than 70 years of age admitted for uncomplicated lumbosciatica suggestive of disk herniation, we sent a 43-item questionnaire to 106 rheumatology departments in France. The questionnaire collected information on hospital stay duration, modalities of rest, drug treatments, local glucocorticoid injections, physical treatments, sick leave duration and advice given to the patients. The response rate was 77% (84 questionnaires). Substantial variations were found across departments. Hospital stay duration ranged from five to 20 days and nonsteroidal antiinflammatory drug treatment duration from five to 30 days. Local glucocorticoid therapy was given as one to four injections at intervals of two to seven days. Spinal traction was used in 38% and a corset in 50% of study centers. Neither was there any consensus regarding immediate or delayed physiotherapy. Most respondents recommended bedrest for no longer than 15 days, a nonsteroidal antiinflammatory drug, a level I or II analgesic, local glucocorticoid injections and, in the event of persistent pain at the end of the hospital stay, a lumbar corset.

Aged↗