Expression of platelet-activating factor receptor in human carotid atherosclerotic plaques: relevance to progression of atherosclerosis.

BACKGROUND: Human monocyte-derived macrophages synthesize numerous proinflammatory and prothrombotic substances, including lipid mediators, such as platelet-activating factor (PAF), which may play a major role in the onset and perpetuation of atherosclerotic lesions. In addition, both monocytes and macrophages express PAF receptors (PAF-R). The expression of PAF-R is transcriptionally downregulated by oxidized LDL in in vitro primary cultures of monocyte/macrophages. In this study, we evaluated the expression of PAF-R in human carotid plaque tissue, in foam cells isolated from human carotid plaques, and in primary cultures of umbilical smooth muscle cells (SMCs). METHODS AND RESULTS: We show that PAF-R was expressed at low levels in foam cells compared with monocyte/macrophages in plaques, as assessed by immunohistochemical staining and in situ hybridization. In addition, low levels of mRNA were also detected by RT-PCR in isolated human carotid foam cells. A prominent finding of our study was the demonstration that contractile SMCs were positive for PAF-R, and its mRNA was extracted from primary cultures of umbilical SMCs. CONCLUSIONS: As macrophages loose their inflammatory phenotype on transformation into foam cells, they may equally loose their capacity of defense against aggression. We postulate that the diminished expression of PAF-R may be deleterious in the context of plaque formation and progression. The observation that arterial SMCs of contractile phenotype express PAF-R opens new avenues concerning the migration of these cells from media to intima and atherosclerotic plaque formation.

Liver dysfunction in allogeneic bone marrow transplantation recipients.

Liver dysfunction is common in allogeneic bone marrow graft recipients, but no systematic studies of pre- and posttransplantation liver biopsies have been performed to identify and compare hepatic lesions. This study involved 25 consecutive patients who had undergone serial viral screening tests, liver tests, and pre- and posttransplantation liver biopsy. The aims were to ascertain the origin of liver disorders prior to bone marrow transplantation, to determine the mechanism and severity of liver dysfunction occurring early after transplantation, and to identify a possible relationship between pre-existing liver lesions and the frequency and nature of early liver dysfunction after transplantation. Pretransplantation biochemical liver tests were abnormal in 72% of patients, despite the absence of clinical liver disease. Eleven patients had chronic viral hepatitis B or C. Mild or moderate histological lesions were present in all the patients, with bile duct abnormalities in 48%, central vein abnormalities in 24%, sinusoidal fibrosis in 52%, portal fibrosis in 88%, portal necrosis in 52%, and parenchymal siderosis in 76%. After transplantation, fatal veno-occlusive disease occurred in two patients and biochemical abnormalities occurred in 24. Coded review of needle biopsy specimens failed to provide a single diagnosis. Histological lesions differed between pre- and posttransplantation biopsy specimens only by increased iron overload (96%, P<0.01). We conclude that pretransplant liver lesions contribute to hepatic dysfunction early after bone marrow transplantation, being very similar in nature and degree to lesions observed posttransplantation.

Impact of human immunodeficiency virus infection on the histological features of chronic hepatitis C: a case-control study. The MULTIVIRC group.

Hepatitis C virus (HCV) is frequently encountered in human immunodeficiency virus (HIV)-infected patients because of common routes of transmission. Previous studies suggested that HIV infection impaired the natural course of chronic hepatitis C, with a more rapid progression to cirrhosis. However, these studies did not assess the HIV infection impact on chronic hepatitis C by taking into account the risk factors for liver fibrosis progression: alcohol, sex, age at the contamination, and duration of HCV infection. We studied liver biopsy specimens of 2 groups of 58 patients that were infected by both HCV and HIV or by HCV alone. The 2 groups were matched according those risk factors, and liver biopsy responses were evaluated with the METAVIR items. The METAVIR activity was higher in HIV-positive than HIV-negative patients. Cirrhosis was more frequent: (1) in HIV-positive patients with CD4 < or = 200 cells/microL (45%) than in HIV-negative patients (10%) (P = .003), (2) in HIV-positive patients with CD4 < or = 200 cells/microL (45%) than in HIV-positive patients with CD4 > 200 cells/microL (17%) (P = .04). These differences, which were linked to HIV status, might be related to the enhanced HCV replication during HIV infection or other immune mechanisms that need further studies.

Low hepatic iron concentration: evaluation of two complementary methods, colorimetric assay and iron histological scoring.

AIMS: To validate a method of assessment of low hepatic iron concentration based on a biochemical colorimetric assay plus histological scoring. METHODS: The within-day and day to day precision of the iron colorimetric assay was determined on frozen rat liver. The coefficient of variation (CV) of iron measurement in two separate samples from the same liver was determined for 21 deparaffinised human biopsies. The intra- and interlaboratory variability of the colorimetric assay and histological scoring were assessed on 38 deparaffinised liver biopsies. RESULTS: For the within-day test, the CV was 11% (5.1 (0.6) mumol/g dry weight (dw), mean (SD) iron concentration). For the day to day test, the CV was 19.5% (8.2 (1.6) mumol/g dw). The CV was 14.7% for iron concentration determined in two separate samples from the same liver. By correlation and kappa concordance tests, the intra- and interlaboratory variability of the hepatic iron colorimetric assay and iron histological scoring was slight. Absence of stainable iron corresponded to a liver iron concentration < or = 20 mumol/g dw. CONCLUSIONS: A combination of two complementary methods, colorimetric measurement and histological scoring, is an accurate and reliable way of determining low iron concentrations in deparaffinised human liver biopsies. In secondary haemosiderosis, such methods would be essential for investigating the role of low iron overload in fibrogenesis and during the response to antiviral treatment in chronic viral hepatitis.

Evaluation of combinations of titanium, zirconia, and alumina implants with 2 bone fillers in the dog.

The quality of the tissue-implant interface was evaluated using light and scanning electron microscopy with morphometric analysis. Nine dogs were implanted with 3 types of dental implants (titanium, zirconia, or alumina). A total of 24 dental implants was placed in mandibular bone previously filled with coral carbonate calcium (corail) or hydroxyapatite. The study results in breaking the concept of osseointegration into 2 phases: "osseocoaptation," which concerns only the interface (physical contact between the implants and the bone without interpenetration process), and "osseocoalescence," which relies on an interpenetration of the bioactive material, which almost entirely disappears, being substituted by newly formed bone. There was no significant statistical difference between the 3 types of implants. Both fillings showed good ossecoalescence properties. However, hydroxyapatite led to fibrous encystment, preventing osseocoaptation of implants. In contrast with calcium carbonate filling.

Alteration of cytokeratin expression in oral lichen planus.

The purpose of this investigation is to examine the possible biochemical and topographic cytokeratin alterations in lichen planus of oral mucosa. Biopsy samples of clinically normal buccal mucosa (n = 5), normal gingiva (n = 5), lichen planus from buccal mucosa (n = 5), and lichen planus from gingiva (n = 5) were obtained from patients of both sexes. Cytokeratin expression was determined by means of immunohistochemical labeling with use of a battery of monoclonal antibodies against cytokeratins and filaggrin and two-dimensional gel electrophoresis. In buccal mucosa, which is not keratinized cytokeratins 4 and 13 are expressed in the majority. In buccal mucosa lichen planus, the appearance of cytokeratins 1, 2, 10, and 11 coincides with a decrease in cytokeratins 4 and 13 and a moderate increase in cytokeratins 6, 16, 17, and 19. In normal gingiva, which is normally keratinized, the main cytokeratins are 1, 2, 10, and 11. In gingival lichen planus, a slight decrease in these cytokeratins and in cytokeratin 13 expression was noted. Finally, alterations in cytokeratins 5 and 14, explained by marked alterations of basal cells, were observed. The battery of antibodies used in this study, in correlation with two-dimensional gel electrophoresis, could represent useful diagnostic tools that enable the distinction between inflammatory keratosis and so-called quiescent lichen planus. Moreover, this work showed that cytokeratins 1, 2, 10, and 11 and filaggrin are sensitive tools that may help detect early relapse before clinical exacerbation. Finally, these biochemical techniques may be useful to follow the evolution of lichen planus under treatment.

[Undifferentiated carcinoma with lymphoid stroma (undifferentiated carcinoma nasopharyngeal type?). Optical, electron microscopical and immunofluorescence study (author's transl)]. / Carcinome indifférencié à stroma lymphoïde de la parotide (Carcinome indifférencié de type nasopharyngé ?). Etude en microscopie optique, életronique et en immunofluorescence.

A case of undifferentiated carcinoma with lymphoid stroma of the paired gland is reported in a chinese woman with positive Epstein-Barr virus serology. The histologic appearance of the tumor is very similar to undifferentiated carcinomas nasopharyngeal type (UCNT). Ultrastructural study reveals features of epidermoid differentiation. Immunofluorescence study shows numerous and predominant IgA plasma cells in the stroma. The relationship between this tumor and the benign lymphoepithelial lesions of the salivary glands are discussed. The present case and the review of the literature emphasize the morphological and epidemiological similarities between UCNT and undifferentiated carcinoma with lymphoid stroma of the salivary glands.

[Cells of the conduction pathways of the human bundles of His. Histoenzymologic and ultrastructural study]. / Les cellules des voies de conduction dans le faisceau de His humain. Etude histoenzymologique et ultrastructurale.

A human His bundle was studied two hours after death by histoenzymological techniques and electron microscopy. The pathway had a much higher cholinesterase activity than the working myocardium, due to its richness in nerve endings: this was confirmed by electron microscopy which also distinguished "common" contractile cells (working cells) from P type and "intermediary" cells; those were by far the most common, presenting an ultrastructure identical to that of the Purkinje cells, classically described in the bundle branches alone. These findings and the unique longitudinal architectural organisation of the His bundle, confirm the studies of JAMES and may explain the rapidity of conduction in this structure.

[Interferon alpha-2a treatment of 26 patients with chronic non-A non-B hepatitis. Predictive factors of response]. / Traitement par l'interféron alpha-2a de 26 cas d'hépatites chroniques non A-non B. Etude des facteurs prédictifs de réponse.

The type and predicting factors of response to alpha interferon therapy have been studied in 26 patients with chronic non-A non-B hepatitis. Interferon was administered three times weekly during 6 months at a dose of 3 millions units/day. Eleven patients (42 percent) had serum alanine aminotransferase levels below 1.5 times the upper limit of normal range at the end of treatment. Only eight (31 percent) patients had persistent normalization of seric alanine aminotransferase value, 6 months after the end of the interferon treatment. The main factors involved in the response to therapy were age, apparent duration of the disease, and mode of contamination: patients who responded to interferon were younger, had a shorter duration of hepatitis and a parenterally transmitted disease.

[Polyneuropathy disclosing primary Gougerot-Sjögren syndrome. Treatment by plasma exchange]. / Polyneuropathie révélatrice d'un syndrome de Gougerot-Sjögren primitif. Traitement par échanges plasmatiques.

A 27 year-old woman presented with a sensory-motor polyneuropathy, right facial hypoesthesia and bilateral Adie syndrome. These led to the diagnosis of primary Gougerot-Sjögren syndrome. A 6 weeks therapy with corticoids brought no improvement. Frank improvement followed 12 plasmatic exchanges.

[Malignant fibrous histiocytoma of soft tissue: atypical presentations. Value of combined surgery and chemotherapy]. / Histioctome fibreux malin des tissus mous: présentations atypiques. Intérêt de l'association chirurgie-chimiothérapie.

The authors report five cases of malignant fibrous histiocytoma of the soft tissues, some of them with atypical presentation (necrotizing tumor, hypereosinophilic syndrome, dermatomyositis). This is the first case of polymyositis associated with malignant fibrous histiocytoma. The tumor occurs between the fifth and the seventh decade, principally as a mass on the proximal lower limb. Local recurrence and metastasis occurs in 50% of patients. Prognosis is dependent on both the surgical possibilities and the characteristics of the tumor (site, size, histologic grade). Surgery alone is inadequate. Adjuvant chemotherapy improves the 5-year survival.

[Peroperative circulatory arrest during excision of an unrecognized thoracic pheochromocytoma]. / Arrêt circulatoire per-opératoire au cours de l'exérèse d'un phéochromocytome thoracique méconnu.

The authors present a case of thoracic phaeochromocytoma responsible for cardio-circulatory arrest during thoracotomy for mediastinal tumour. In such cases, hypertension must be controlled with phentolamine or sodium nitroprusside, cardiac arrhythmia with lignocaine, and collapse with volaemic expansion. The medical literature concerning thoracic phaeochromocytoma is briefly reviewed.

[Idiopathic white atrophy causing cutaneous thrombotic microangiopathy. Apropos of a case]. / L'atrophie blanche idiopathique cause de microangiopathie cutanée thrombosante. A propos d'un cas.

Authors report clinical data on a 59-year-old woman, bearing, since 15 years, painful purpuric and necrotizing macules and papules on the legs, leading to white atrophic scars. On examination one could see lesions in various stages of development. Clinical examination and all laboratory investigations were otherwise normal. First cutaneous biopsy led to an erroneous diagnosis of vasculitis with subsequent corticotherapy. Second biopsy displayed numerous fibrinous thrombi inside lumens of superficial dermal capillaries without fibrinoid necrosis of their parietal layer nor inflammatory infiltrate. A diagnosis of white atrophy was made on the coexistence of clinical and histopathological data, according to Shornick's criteria. Drastic improvement of clinical condition was obtained with heparin therapy. White atrophy is a clinicopathological entity first described in 1929 by Milian, then by Nelson in 1955. Authors describe here its main clinical data with diagnostic considerations and pathophysiology.

[Chordomas]. / Chordomes.

Chordomas are slowly growing malignant tumors arising from notochordal rests. They are occurring in adults (50 to 60 year old) and are mainly (85%) located in sacrococcygeal or spheno-occipital regions; other main localization is cervical spine. Chordomas are usually discovered in patients with pain or symptoms due to compression of surrounding viscera. Radiologically it is characterized by association of osteolysis and soft tissues opacity. On macroscopic examination tumoral tissue has mucoid appearance; under microscope it is made up with lobules of epithelial-appearing cells surrounded by acid mucosubstances. Tumorous cells contain glycogen and neutral mucosubstances. They are surrounded by argyrophilic rim due to pericellular condensation of intercellular matrix, well viewed on electron microscope examination. When their cytoplasm is filled with vacuoles, cells take up typical physaliphorous appearance. Chordomas cells express epithelial differentiation antigens (low molecular weight cytokeratins, EMA, CAM 52, HFM 62, even CEA), Vimentin and S-100 Protein: this triple positivity allow differentiation between chordomas and numerous others tumors. Correct treatment of chordoma is achieved with an initially complete excision. Local recurrences are frequent and sometimes inoperable: in this cases radiotherapy alone may be performed (70 grays). Sarcomas (fibroblastic or Malignant fibrous histiocytoma) may occur after radiotherapy or without it. Hematogenous metastasis occur in 10% to 15% of patients. Survival rate at five years is included between 50% and 75%. Chondroid chordoma is a special entity occurring in younger patients (35 year old) and located in spheno-occipital region. In addition to chordomas it contain chondroid (benign or malignant) islands. Mean survival rate (16 years) is far better than for chordoma or chondrosarcoma.

[Undifferentiated clear cell thyroid carcinoma. Diagnostic interest of ultrastructural study (author's transl)]. / Carcinome indifférencié à cellules claires de la thyroïde. Intérête diagnostique de l'eétude ultrastructurale.

Optical and electron microscopy features of an undifferentiated clear cell carcinoma of the thyroid are presented. Tumor cells have irregular, often multiple nuclei, showing numerous mitosis. Diastase-digested P.A.S. positive material is demonstrated in their cytoplasm. Numerous lymphocytes and plasma cells are present in the stroma. Electron microscopy showed large cytoplasmic areas of monoparticular free glycogen, few lipid droplets, numerous desmosomes and some intercellular microvilli. Most cells contained varying amounts of tonofilament bundles suggesting a partial epidermoid differentiation. This atypical appearance has not been described in metastases from clear cel carcinoma of kidney and may assist the primary nature of undifferentiated clear cell thyroid carcinoma.

[Endometrial stromal tumor associated with rhabdoid phenotype and and zones of "sex cord-like" differentiation]. / Tumeur stromale de l'endomètre associant un phénotype rhabdoïde et des zones de différenciation "sex cord-like".

An unusual endometrial stromal sarcoma is described in a 50-year-old patient. The distinctive feature of this case is the focal occurrence of sex cord-like pattern and rhabdoid appearance of tumor cells. Rhabdoid cells have an eosinophilic cytoplasm and a vesicular nucleus with a prominent nucleolus. Immunohistochemistry showed positive cytoplasmic staining for both cytokeratin and vimentin, and ultrastructural examination identified tumor cells with abundant cytoplasmic intermediate filaments. To our knowledge, only one case of endometrial stromal sarcoma with this unusual morphological association has been reported in the literature.

[Basal cell adenoma of the parotid. Apropos of a case with an ultrastructural study]. / Adénome à cellules basales de la parotide. A propos d'un cas avec étude ultrastructurale.

A case of Basal cell adenoma occurring in a 42 year-old woman is reported. Histological examination showed trabeculae of basaloid cells with thick Basal Membrane at the periphery. By Electron Microscopy most of the cells displayed numerous desmosomes and intracytoplasmic tonofilaments indicating epidermoid differentiation. In addition some glandular cells were observed. No myoepithelial cell were present. Electron Microscopy may be useful to differentiate basal cell adenoma from Adenoid cystic carcinoma which is made up of a majority of poorly differentiated cells.

[Visceral histologic lesions of lethal acute colchicine poisoning. Apropos of 12 cases]. / Lésions viscérales histologiques des intoxications aiguës mortelles par la colchicine. A propos de 12 observations.

The authors reported histological characteristics (on post-mortem examination) of 12 cases of lethal acute colchicine intoxication and compare these results with the 5 previous anatomical studies of such cases in the literature. Abnormal mitosis (stathmocinesis, "caryomerie", caryorrhexis and mitonecrosis) are constant and essentially seen in the bone marrow and digestive mucosae, especially in oesophagus which squamous epithelium is more resistant to autolysis than others digestive mucosae. Biological or histological symptoms or lesions of intravascular diffuse coagulation are present 7 cases but both biological and histological manifestations in only one case. Hematological disorders are constant when more than 0.5 mg/kg (of corporeal weight) of colchicine has been ingested. Granulocytic elements are most affected both by hypoplasia (essentially in the first four days) and maturation troubles. A microvacuolar non systematized and diffuse liver fatty change is found in 10 cases, probably related to alteration of lipoproteins synthesis and secretion by hepatocytes. Interstitial myocardial oedema is a constant feature; in addition true interstitial myocarditis (with infiltration by polymorphs) is seen in two cases. These cardiac lesions may be related to the cardiogenic shock which is often observed in these patients.

[Apparently isolated case of African Burkitt lymphoma localized in the breast]. / Lymphome de Burkitt africain à localisation mammaire apparemment isolée.

We report a case of unilateral primary Burkitt lymphoma of the breast. It occurred in a young woman with a history of recent abortion, as a painful mass confused with an abscess. The diagnostic was suggested after fine needle aspiration. Biopsy allowed confirmation, by revealing a B-phenotype lymphoma with intranuclear Epstein-virus small RNA (EBER) in all cells. Additional investigations (clinical and radiographic) were negative (no lymphadenopathy). Chemotherapy induced rapid and complete remission. Patient is in good health (no local recurrence) 5 years later.

[Breast chondrosarcoma: a case report and review]. / Chondrosarcome du sein: à propos d'un cas.

Sarcomas of the breast are relatively rare and account for 1% of all primary malignant tumors of the breast. Only 4 cases of pure chondrosarcoma of the breast have been published. We report an additional case in a fifty-seven-year-old woman. Histological and immunohistological characteristics were similar to those described in other localizations. Differential diagnosis involves cystosarcoma phyllodes and breast metaplastic carcinoma with chondroid differentiation. The prognosis is likely to be the same as in other chondrosarcomas.