Extra-cellular matrix rigidity may dictate the fate of injury outcome.

After injury, while regeneration can be observed in hydra, planaria and some vertebrates, regeneration is rare in mammals and particularly in humans. In this paper, we investigate the mechanisms by which biological tissues recover after injury. We explore this question on adipose tissue, using the mathematical framework recently developed in Peurichard et al., J. Theoret. Biol. 429 (2017), pp. 61-81. Our assumption is that simple mechanical cues between the Extra-Cellular Matrix (ECM) and differentiated cells can explain adipose tissue morphogenesis and that regeneration requires after injury the same mechanisms. We validate this hypothesis by means of a two-dimensional Individual Based Model (IBM) of interacting adipocytes and ECM fiber elements. The model successfully generates regeneration or scar formation as functions of few key parameters, and seems to indicate that the fate of injury outcome could be mainly due to ECM rigidity.

Cold climate could be an etiologic factor involved in Raynaud's phenomenon physiopathology. Epidemiological investigation from 954 consultations in general practic.

AIM: The physiopathology of Raynaud's phenomenon (RP) is not currently fully resolved. The cold seems to be not only an important factor triggering attacks, but also inducing RP. The aims of this study were to assess the prevalence of RP in Nantes urban district, and study the relationship between RP prevalence and cold climate. METHODS: Patients aged between 10 and 80 years old, consulting in five Nantes General Practices, from June 2011 and March 2012, were included. Patients presenting RP underwent a full clinical examination. Subjects not meeting Allen and Brown criteria benefited from at least a dosage of Anti-Nuclear Antibodies and a naifold Capillaroscopy. Climate data provided by French national weather agency allowed establishing an average of observed temperatures during the past five years and correlating them to the observed prevalence. RESULTS: Of 954 patients included, 78 had a RP, for an overall prevalence estimated at 8.2%. The prevalence among women (8.9%) was slightly higher than men (7.3%). Secondary form represented 5.1% of RP. In the RP group, 13 patients were active smokers, mean BMI was 22.3±3.2 kg/m², and only 4 patients were treated by vasoconstrictor therapy. According to French national weather agency, between 2007 and 2011, mean temperature of January in Nantes area was 5.8 °C. CONCLUSION: We confirmed that the lower winter temperatures a region experiences, the higher the prevalence of RP, thus raising the question of the physiopathological role of the cold in the induction or in the revelation of RP.

IgA nephropathy and alcoholic liver cirrhosis. A prospective necropsy study.

The incidence of mesangial IgA nephropathy (mIgAN) was investigated in a series of patients with alcoholic liver cirrhosis (ALC). Biologic parameters classically reported in IgAN were assessed in 98 patients, namely hematuria, proteinuria, and serum IgA. An immunohistologic study of the liver and kidney was performed in 33 patients who died during the study. Renal data were compared with those obtained in a matched necropsic series of controls. This study confirmed a global elevation of serum IgA levels in ALC. A possible hepatic origin of these immunoglobulins was supported by the observation of plasma cells in portal spaces in 68% of the patients. Biologic signs of renal disease consistent with mIgAN were observed in 16% of the patients; IgAN was diagnosed in 18% of patients with ALC and 10% of the controls. These data suggest that the incidence of mIgAN in ALC is not different than in the general population.

Osteoid osteoma of the rib: a case report.

A case of a 6-year-old boy with a painful dorsal scoliosis secondary to an osteoid osteoma in a rib is described. Surgical excision was performed and the scoliosis decreased. Such cases are very rare.

[Histological and immunohistochemical diagnosis of bone marrow metastases of neuroblastomas]. / Diagnostic histologique et immunohistochimique des métastases ostéomédullaires des neuroblastomes.

A retrospective, morphological and immunochemical study was performed on 60 bone marrow biopsies (BOM) and 12 tumor specimens surgically excised, from 9 patients with neuroblastoma (NB). Immunochemistry concerned "neuron-specific enolase" (NSE), chromogranin A (CGA) and synaptophysin (SP). The results of immunochemical stains and the study of reticulin network on the argentic stain were compared to the results of morphological evaluation on the routine stain. NSE, CGA and SP staining of tumor cells (part or all of them) was obtained from all surgical specimens. 17/75 BOM (20%) were discarded because of poor material. NB cells were observed in 24 BOM from 3 patients. Tumor cells formed large strands (1 patient) or nests (2 patients) associated with segregated cells. Diagnosis of metastatic BM involvement was negative or doubtful for 6 BOM (3 obtained at the same time, 2 patients), in which NB cells were clearly demonstrated by immunochemical staining of NSE and/or CGA. Reticulin and/or collagen myelofibrosis was present in 32/35 BOM from the 3 patients metastatic in bone marrow (BM+) even if NB cells could not be demonstrated in these samples.

Cystic degeneration in non-ossifying fibroma.

Two unusual cases of non-ossifying fibromas in boys of 4 years with partial cystic degeneration are presented. The osseous cavities did not respond to corticosteroids.

[Fibrolipomatous hamartoma of the peripheral nerves. Anatomico-clinical study of 5 cases, including 2 with ultrastructural study]. / Hamartome lipofibromateux des nerfs périphériques. Etude anatomo-clinique de 5 cas dont 2 avec étude ultrastructurale.

Five cases of fibrolipomatous hamartoma are described. The median nerve was involved in four cases, the medial plantar nerve in one case. In the two cases with involvement of the median nerve in the wrist, the diagnosis was macroscopically suspected on the typical fusiform, segmentary enlargement of the nerve by fibrolipomatous tissue. Histologically, the epineurium was expanded by fibrolipomatous tissue and the scattered nerve bundles were dissociated by perineurial and endoneurial fibrosis. At ultrastructural examination the nerve bundles were constituted of "onion bulblike formations" with one or two central nerve fibers and peripheral perineurial cells. Eighty-eight cases of fibrolipomatous hamartoma were published in the medical literature, thirty-six with macrodactyly. This rare and probably congenital affection frequently involve the median nerve (78%).

[Role of the pathologist in the treatment of osteosarcoma]. / Rôle du pathologiste dans le traitement des ostéosarcomes.

We describe the pathological method for the study of osteosarcoma surgical specimens treated by chemotherapy according to Rosen and Huvos. The aims of this method are to assess the extent and the histological viability of each tumor after chemotherapy. The borderline between good and bad response is about 5% viable tumor cells. This histological response determines postoperative chemotherapy.

[X-ray computed tomographic aspects of tumors of the colon with peripheral extramucous development]. / Aspects scanographiques des tumeurs du côlon à développement extra-muqueux périphérique.

The authors report three cases of a palpable abdominal mass without clinical evidence of obstruction. In each case, ultrasound diagnosed a solid tumor. Computer tomography examination measured the density of the tumor and the extension of the disease. In each case, the colonic origin was established owing to surgery. Histological examination of the three cases diagnosed a fibroma of the caecum, an enterogenic cyst of the caecum and a T-lymphosarcoma developed from the wall of the left colon.

[Evaluation of the histopathologic effects following subconjunctival injection of corticoids in immediate- and retard-action forms]. / Evaluation des effets histopathologiques secondaires aux injections sous-conjonctivales de corticoïdes en formes immédiates et retard.

We comparatively studied histopathologic impairments following subconjonctival injections of long and short acting corticosteroids and saline. 44 conjunctival biopsies were performed in the site of injection. The tissues were evaluated by light and electron microscopy. The histopathologic findings, following saline subconjonctival injection were very slight. On the other hand, histopathologic findings following corticoids injection, and particularly long action products, were remarkable. We noted crystalline deposits inclusions of drug particles in fibroblast and macrophages, loss of collagen definition and degenerative changes of these phagocytosing cells, with release of their cytoplasmic contents. Our findings are according with previous studies about long acting corticosteroids, supporting their relative histologic toxicity, by local way of administration.

[X-ray computed tomography and synovial chondrometaplasia]. / Scanographie et chondrométaplasie synoviale.

Scanography allows diagnosis of radiotransparent intra-articular foreign bodies and establishment of their synovial origin, sometimes even in the absence of joint opacification. It provides an overall assessment of the joint that can be improved by arthrography. Clinical and standard radiologic pictures of primary synovial chondrometaplasia (synovial osteochondromatosis) and intra-articular foreign bodies can cause confusion if the latter are modified by secondary chondrometaplasia. Scanographic analysis of islets of chondrometaplasia suggests their primary nature in the presence of plaques of calcification of a small size, of low density and diffused throughout the image while peripheral, lamellar, dense calcifications are suggestive of secondary lesions.

[Extension to the thoraco-abdominal wall of actinomycoses. Value of computed tomography]. / Extension à la paroi thoraco-abdominale des actinomycoses. Intérêt de la scanographie.

Four patients with deep visceral actinomycosis infections presented evidence of extension to the thoracic or abdominal wall. Investigation of the chronic parietal suppuration by CT scan imaging allowed definition of the nature and extent of parietal infiltration, and notably to demonstrate its anatomical continuity with the often unrecognized deep focus: chronic lung disease, appendicular or colon mass, chronic genital infection in patients with intra-uterine device.

[Drug-induced pulmonary diseases: diagnostic, therapeutic and prognostic aspects. Apropos of 10 personal case reports]. / Pneumopathies médicamenteuses. Modalités diagnostiques, thérapeutiques et pronostiques. A propos de 10 observations personnelles.

The authors report ten cases of drug induced lung diseases, complicated by respiratory failure of whom five were attributed to cytotoxic drugs and five to non cytotoxic drugs. The drug induced lung disease presented as acute respiratory distress syndrome in two cases, alveolar interstitial lung disease in three cases, purely interstitial in five cases. There was acute respiratory failure (ARF) in eight cases and chronic respiratory failure (CRF) in two cases. Among the five patients admitted for cytotoxic drug induced lung disease and ARF, four recovered and one died of diffuse destructive pulmonary fibrosis. Among the five patients having non cytotoxic drug induced lung disease, three were in ARF and recovered. The other two had CRF and died of diffuse pulmonary fibrosis. The diagnostic of drug induced lung disease was established in each case with the chronology of the clinical events, the exclusion of other possible causes of the lung disease and the evolution after removal of the incriminated drug. Broncho-alveolar lavage (BAL) had a major diagnostic value. It was contraindicated by respiratory failure in five cases. The predominant alveolar cell type was lymphocyte (four cases), eosinophil (three cases) and neutrophil (one case), BAL was realized with a provocation test and demonstrated the pathogenic role of cyclothiazide in one case. No specific information was given by histology. The prognosis did not seem to be linked to the severity of the initial clinical picture, or to the nature of the underlying neoplastic disorder, but to the degree and evolution of the pulmonary fibrosis.