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M Petein

Publications and source records attributed to M Petein.

67 records · Page 4Linked to original sources
PubMedDate not supplied

Decreased immunoreactive maspin expression in intermediate thickness and thick primary melanoma lesions.

Maspin is a member of the serpin family of protease inhibitors. It is a 42 kDa cytoplasmic protein that is reported to have tumour suppressor activity. The loss of maspin gene expression is correlated with increased invasiveness and the risk of metastases in breast cancer. We studied maspin expression in primary melanoma lesions obtained from 76 patients. Immunostaining of 5 pm sections for maspin expression was obtained using the citrate antigen retrieval method. The extent of immunostaining was scored by recording the proportion of immunoreactive cells and the intensity of immunostaining. Our results demonstrated that maspin expression was down-regulated in intermediate thickness and thick melanoma lesions compared with thin lesions. These results suggest that loss of maspin expression might play a role in melanoma progression, invasion and metastatic dissemination. Further studies are needed to clarify the clinicopathological significance of maspin expression in melanoma.

Adult↗
PubMedDate not supplied

[Malignant retroperitoneal paraganglioma. Case report and literature review].

The authors report a case with a retroperitoneal recurrent malignant non-secretory neuroendocrine tumor. The diagnosis of this rare pathology is based on immunohistochemical and electron microscopic techniques. Due to radio- and chemotherapeutic resistance of the tumor, the therapy has to be surgical. The locoregional recurrent nature of the disease asks for a close clinical and radiological follow-up.

Female↗
PubMedDate not supplied

In vitro evaluation of the marginal seal of four restoration materials on deciduous molars.

The aim of this study was to compare the marginal microleakage of Fuji II LC (A), composite resin Z250 (B), Fuji IX GP (C), and Dyract AP (F) in class V cavities and at the Fuji II LC/Z250 (D) and Fuji IX GP/composite resin Z250 (E) interfaces of an open sandwich technique on deciduous teeth. After thermocycling the mean marginal dye penetration at the enamel junction was 21.6 microns +/- 14.2 for group A; 83.6 microns +/- 32.3 for group B; 7.5 microns +/- 7.5 for group C; 38.7 microns +/- 27.5 for group D, and 0 micron for groups E and F. Mean dye penetration at the cementum junction was 37.1 +/- 20.2 (A); 123 +/- 42.1 (B); 28.7 +/- 17.1 (C); 0 (D); 14.4 +/- 14.4 (E); and 0 (F) microns. No leakage was seen at the junction between Fuji II LC and Z250 (0 micron), whereas a mean leakage of 184 microns between Fuji IX and Z250 was measured. In enamel the best seal was obtained with Dyract AP, but with differences at the limit of significance (P = 0.07). Sealing was significantly worse with Z250 (p = 0.03 versus Fuji II LC; p = 0.006 versus Fuji IX GP; and p = 0.003 versus Dyract AP). In cementum, the comparison between the grouped data Z250-Fuji II LC versus Fuji IX GP-Dyract AP was highly significant (p < 0.001), while there was no detectable difference between Z250 and Fuji II LC.

Coloring Agents↗
PubMedDate not supplied

Renal pelvis haemangioma demonstrated by MSCT urography with ureteral compression and 3D reconstruction.

A rare case of renal haemangioma of the renal pelvis is reported. The 40-year-old patient classically presented with recurrent hematuria. The small pyelic tumour was clearly delineated by msCT urography obtained during compression of the uretera with rubber balloons classically used during IVP In the absence of a definite histological diagnosis--pyeloscopy being unsuccessful--the patient underwent radical nephrectomy. The literature concerning renal haemangioma is briefly reviewed and the role of compression assisted msCT urography as a possible method for the detection of small pyelocaliceal tumours is emphasized.

Adult↗
PubMedDate not supplied

Influence of suramin alone or in combination with DHT and PDGF on the cell proliferation of benign and malignant human prostatic tissues in organ cultures.

We studied the suramin-induced influence on the cell proliferation of 16 benign and 6 malignant lesions of the human prostate maintained in vitro as organ cultures. The cell proliferation was assessed by nuclear labeling with tritiated thymidine autoradiography. We also studied the dihydrotestosterone (DHT)-and platelet-derived growth factor (PDGF)-induced modulation of suramin influence on such prostate organ culture cell proliferation. Our results indicate that more than half of the benign prostatic tissues showed cell proliferation which was modulated by DHT and/or PDGF, while none of the six carcinomas responded to such hormonal stimulation. Suramin alone inhibited the cell proliferation of only 19% of the prostate organ culture under study, while in combination with DHT and/or PDGF this inhibition level reached 48%. However, we occasionally observed that S alone or in combination with DHT and/or PDGF was also able to stimulate prostate cell proliferation. We think that organ cultures of human prostatic tissues might represent a helpful pre-clinical tool to study the anti-tumoral influence of suramin, which is a new antineoplastic generative compound.

Adult↗
PubMedDate not supplied

[Osteoradionecrosis at the level of coxo-femoral articulation in the adult].

Two cases of either cervical or acetabular osteoradionecrosis were described. One patient had endoprosthetic replacement of the hip, the other did not receive any surgical treatment. Regarding the literature, osteoradionecrosis occurs in 0.3 to 4% of the irradiated bones. Histologically there is a destruction of the bone by direct toxicity of the radiation and by destruction of the vascular supply. The threshold of irreversible bone destruction is 30 Gy. Fractures are epiphenomenons of osseous radionecrosis. The diagnosis can be suspected either by radiographies or by bone scans. Sometimes a bone biopsy is necessary to differentiate between bone necrosis, bone metastasis and eventually a radiation-induced sarcoma of the bone. If the osteoradionecrosis affects the acetabulum, even in the case of a stress fracture without acetabular protrusion of the femoral head, no surgical treatment is recommended. Weight bearing is avoided and spontaneous resolution occurs in most cases. If, on the other hand, there is a fracture through the femoral neck, hemiarthroplasty or total joint replacement is the treatment of choice. Total joint replacement is also recommended in case of an extensive radiation induced coxopathy.

Acetabulum↗
PubMedDate not supplied

In vivo interaction of AR-L 115BS (Vardax) with the adrenergic nervous system.

In vitro studies have demonstrated that AR-L 115BS (AR-L), a new orally active nonglycosidic inotropic agent with vasodilator properties, does not act via adrenergic receptors. However, because AR-L is a phosphodiesterase inhibitor and interaction with the adrenergic nervous system may exist in vivo, we compared the actions of intravenous AR-L, isoproterenol, and propranolol, alone and in combination, in normal dogs. In seven awake morphine-sedated dogs, AR-L (4 mg/kg i.v.) did not alter circulating catecholamines despite increasing maximum rate of change of left ventricular pressure (dP/dt) by 76%. In anesthetized dogs, peak inotropic effect of AR-L occurred at 6 mg/kg (dP/dt from 5,450 +/- 1,280 to 12,000 +/- 3,050 mm Hg/s). Propranolol (1 mg/kg) depressed dP/dt from 5,725 +/- 2,032 to 2,530 +/- 631 mm Hg/s, and this was completely reversed by increasing doses of AR-L (2-30 mg/kg) but the maximum dP/dt attained in these dogs (6,050 +/- 221 mm Hg/s) remained below the level achieved by AR-L in the absence of propranolol. To determine if that difference was due to an interaction of AR-L with the adrenergic nervous system, the effect of AR-L on isoproterenol activity was studied in groups of beta-blocked and unblocked animals. In either group, the dose-response curve of dP/dt to isoproterenol was shifted upward by AR-L, but the actions of the two drugs were additive without real synergism (e.g., after propranolol:isoproterenol 10 micrograms/min 73%; AR-L 6 mg/kg 81%; both 160%. In unblocked dogs, the results were: isoproterenol 2 micrograms/min 96%; AR-L 1 mg/min 39%; both 138%). Similarly, isoproterenol and AR-L were only additive in their effects on heart rate and systemic vascular resistance. Thus, although AR-L is a phosphodiesterase inhibitor, its predominant mechanism of action appears to be independent of the adrenergic nervous system.

Animals↗
PubMedDate not supplied

Digital cell image analysis of Feulgen-stained nuclei from human papillary, medullary, colloid, lobular and comedocarcinomas of the breast.

The morphonuclear characteristics (nuclear size and chromatin pattern), the proliferation index and the ploidy level were characterized in a series of 46 breast tumors including medullary (5 cases), papillary (6 cases), lobular (27 cases), colloid (4 cases) and comedo- (4 cases) carcinomas. The quantitative assessments were carried out by means of digital cell image analyses of Feulgen-stained nuclei from imprint smears. The results show that monovariate analyses (one-way variance analyses) were much less potent than multivariate analyses (principal components analyses followed by the canonical transformation of the data and discriminant analyses) in assessing the morphonuclear characteristics of these breast tumors. The multivariate analyses indicated that there might be a level of malignancy which increases according to the sequence papillary and medullary and colloid carcinomas-->comedocarcinomas-->lobular carcinomas. This assertion is corroborated by the ploidy-level-related results which revealed a higher proportion of highly aneuploid cases in the group of lobular carcinomas than in the group which included medullary, papillary and colloid carcinomas. However, since highly aneuploid cases were also encountered in this latter low malignancy level group, we expressed the hypothesis firstly that aneuploidy reflects two distinct biological properties, i.e. the aggressiveness of a tumor and its age, and secondly that a highly aneuploid but low malignancy tumor should correspond to old degenerating tumors.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

DNA histogram typing in human seminomas.

Characterization of the nuclear DNA content (DNA index and DNA histogram type) was carried out in 9 normal testicular tissues and 21 seminomas. Proliferative activity was further determined in the seminomas. Nuclear DNA content was assessed by means of a cell image processor computing the integrated optical density on Feulgen-stained nuclei from formalin-fixed paraffin-embedded materials. The results indicated that the so-called normal testicular tissues exhibited DNA histograms where three cell nuclei populations emerged in varying proportions. These three cell nuclei populations corresponded to haploid, diploid and tetraploid cell nuclei respectively. In contrast, most of the seminomas exhibited monomorphic DNA histogram patterns with a predominance of GO-G1 cell nuclei in the range of the 3c-4c nuclear DNA content. Further studies will be necessary in order to determine whether the DNA histogram has a predictive prognostic value or could be considered as a grading index.

Adult↗
PubMedDate not supplied

Unusual behaviour of the LNCaP prostate tumour xenografted in nude mice.

The tumourigenicity of the LNCaP prostatic cell line was investigated in vivo after prostatic (orthotopic), subcutaneous (ectopic) and concomitant implantations in male Balb/c nude mice. Swollen lymph nodes were detected in the inguinal region only after subcutaneous implantation but could not be characterized by immunohistochemistry. However, when grafted to Endoxan-pretreated mice, they generated well differentiated tumours which secreted prostate-specific acid phosphatase. A parallel study was conducted to investigate the metastatic potential of the LNCaP tumour using several routes of implantation (intravenous, bone contact, intrasplenic and intracranial). Tumours grew only after intracranial implantation. No production of either haematogenous or bony metastases was recorded.

Acid Phosphatase↗
PubMedDate not supplied

Atraumatic splenic rupture in the course of a pneumonia with Streptococcus pneumoniae. Case report and literature review.

Atraumatic splenic ruptures in the course of infectious diseases are rare but have been reported. Various germs of viruses can be at the origin of such rupture. The more often quoted viral disease is infectious mononucleosis. The more frequently involved bacteria are Streptococcus non pneumoniae, Pseudomonas, staphylococci and Clostridium. Rupture mechanism is not clearly elucidated; it can be connected with sepsis diffusion at spleen level via haematogenic way and consequently splenomegaly. Splenic rupture following septicaemia does not always entail major splenomegaly nor abscess formation but the attack of the splenic tissue itself is sometimes sufficient to bring about the rupture. The present case of atraumatic splenic rupture on spleen sepsis, no abscess, starting from a pulmonar infection with Streptococcus pneumoniae is, to our knowledge, the first case reported in literature.

Female↗
PubMedDate not supplied

Difference in glycohistochemical lectin staining of collagen fibers in the corpora cavernosa of normal and impotent men.

The objectives of this study were to investigate the value of glycohistochemical staining with three lectin types specific to a particular glycan structure (Arachis hypogaea [PNA], Triticum vulgare [WGA], and concanavalin A [Con A]) as a method of defining possible changes in the collagen structure in the corpora cavernosa in potent and impotent men. The study group consisted of 4 normal potent men and 22 men with various etiologies of impotence. The quantitative histochemical measurements were performed by means of a cell image processor. Two variables for each of the three types of lectins were studied. These were the mean optical density (MOD), which relates to glycohistochemical staining intensity, and the labeling index (LI), which is positively related to the percentage of immunostaining. Only WGA staining made it possible to discriminate significantly between the normal and pathological groups under study. The two parameters (LI, MOD) were significantly higher in the case of WGA staining in the normal group (P = 0.004 and 0.013, respectively). In contrast, only the mean LI value, in the case of the psychogenic and venogenic patients, reached a level of statistical significance (P = 0.005 and 0.001, respectively), when it increased from PNA through WGA to Con A histochemical staining. The two variables (LI, MOD) changed markedly from PNA through WGA to Con A in the arteriogenic patients (P = 0.003 and P < 0.001, respectively). WGA is of diagnostic value in distinguishing between normal and abnormal collagen in the corpora cavernosa. The difference in the lectin staining of the other groups, particularly the arteriogenic group, may be attributed to alterations in the glycosylation of the procollagen that are probably due to changes in the partial pressure of oxygen (PO2) level, an important cofactor in normal glycosylation. WGA staining may therefore be used as a marker to distinguish true psychogenic patients from those with organic diseases. Moreover, it may be used as an additional parameter in selecting the best candidates for penile revascularization.

Adult↗