Chromatoforoma's bij reptielen

Tumors of the pigment cells or chromatophores in reptiles are classified as melanophoromas, iridophoromas, xanthophoromas, erythrophoromas or mixed type chromatophoromas based on the predominant type of pigment, and constitute a relatively common neoplastic disorder in captive reptiles. Especially melanophoromas and iridophoromas are frequently observed. The diagnosis of chromatophoromas is usually made through histological examination. The use of immunohistochemistry or electron microscopy may be required to discriminate the different types of chromatophoromas. Whenever possible, complete surgical excision is the treatment of choice. Due to the distinct malignancy and tendency to metastasize, the prognosis of cutaneous chromatophoromas in reptiles is generally guarded. Consequently, an early and correct diagnosis of these neoplastic disorders in reptiles is vital. This article provides an overview of the current knowledge regarding the occurrence, the performance, the pathogenesis and the diagnostic and therapeutic approach of chromatophoromas in reptiles with emphasis on melano- and iridophoromas

The shunt from the cyclooxygenase to lipoxygenase pathway in human osteoarthritic subchondral osteoblasts is linked with a variable expression of the 5-lipoxygenase-activating protein

Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels of prostaglandin E(2 )(PGE(2)) or leukotriene B(4 )(LTB(4)) by subchondral osteoblasts, PGE(2 )levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2 (COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low OA osteoblasts subgroup. The addition of PGE(2 )to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup. LTB(4 )levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D(3 )(1,25(OH)(2)D(3)) plus transforming growth factor-β (TGF-β), a situation corresponding to their effect on FLAP mRNA levels. Treatments with 1,25(OH)(2)D(3 )and TGF-β also modulated PGE(2 )production. TGF-β stimulated PGE(2 )production in both OA osteoblast groups, whereas 1,25(OH)(2)D(3 )alone had a limited effect but decreased the effect of TGF-β in the low OA osteoblasts subgroup. This modulation of PGE(2 )production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts compared with normal; however, no relationship was observed overall between IL-18 and PGE(2 )levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE(2 )to LTB(4 )is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is also modulated differently by 1,25(OH)(2)D(3 )and TGF-β depending on their endogenous low and high PGE(2 )levels

La relation chômage-santé : une étude prospective. Présentation sommaire et premiers résultats d’une recherche

Les auteurs ont entrepris en 1984 une importante étude sur les multiples interrelations entre le chômage et la santé. La méthodologie retenue est prospective, longitudinale, avec groupe contrôle. Ils présentent d'abord une synthèse des travaux effectués puis exposent les résultats obtenus jusqu'à maintenant. Ces résultats vont dans le sens des quatre hypothèses posées a priori. Cependant, ces résultats ne sont pas définitifs. L'analyse se poursuit.In 1984, the authors undertook a major study on the multiple interrelations between unemployment and health. Tlie methodology in use is prospective, longitudinal, with a control group. Their presentation consists of a synthesis of work carried out so far followed by corresponding results. These results are in compliance with the four hypotheses developed through a priori reasoning. However, these results are not definitive. The analysis continues

Blunted hypertrophic response in old mouse muscle is associated with a lower satellite cell density and is not alleviated by resveratrol

Background Sarcopenia contributes to the decreased quality of life in the older person. While resistance exercise is an effective measure to increase muscle mass and strength, the hypertrophic response may be blunted in old age. Objectives To determine 1) whether hypertrophy in the m. plantaris of old mice was blunted compared to adult and 2) whether this was related to a reduced satellite cell (SC) density and 3) how resveratrol affects hypertrophy in old mice. Methods In adult (7.5 months, n = 11), old (23.5 months, n = 10) and old-resveratrol-treated (n = 10) male C57BL/6J mice, hypertrophy of the left m. plantaris was induced by denervation of its synergists. The contralateral leg served as control. Results After six weeks, overload-induced myofiber hypertrophy and IIB–IIA shift in myofiber type composition were less pronounced in old than adult mice (P = 0.03), irrespective of resveratrol treatment. Muscles from old mice had a lower SC density than adult muscles (P = 0.002). Overload-induced SC proliferation (P < 0.05) resulted in an increased SC density in old, but not adult muscles (P = 0.02), while a decrease occurred after resveratrol supplementation (P = 0.044). Id2 and myogenin protein expression levels were higher in old than adult muscles (P < 0.05). Caspase-3 was expressed more in hypertrophied than control muscles and was reduced with resveratrol (P < 0.05). Conclusion The blunted hypertrophic response in old mice was associated with a lower SC density, but there was no evidence for a lower capacity for proliferation. Resveratrol did not rescue the hypertrophic response and even reduced, rather than increased, the number of SCs in hypertrophied muscles

Sparte et les gorges du Taygète.

Dedication:Illustration: (Views ,)Pagination: 32PVolumes: 1Text Genre:ProseIllustration: (τοπία ,

Exploiter les résultats d'analyses chimique des sols archéologiques à l'aide des statistiques spatiales

International audienc