Biomedical subjects

Silvano Bosari

Publications and source records attributed to Silvano Bosari.

33 records · Page 2Linked to original sources

PubMed2004

Expression of endothelial protein C receptor and thrombomodulin in the intestinal tissue of patients with inflammatory bowel disease.

OBJECTIVE: Inflammatory bowel diseases are characterized by disorders of immunity, thrombosis of large vessels, and microthrombosis of mucosal vessels. The expression of endothelial protein C receptor (EPCR) and thrombomodulin-two receptors of the protein C pathway involved in thrombin scavenging and inflammation-was studied in intestinal resection specimens or mucosal biopsies from patients with inflammatory bowel disease and from controls. The soluble forms of the receptors in plasma were measured. DATA SOURCE: This study involved patients from two large university hospitals. After surgery or biopsy, tissue samples were either frozen or fixed in formalin and embedded in paraffin. Sections for immunohistochemistry examination were cut and tested with the specific antibodies to EPCR and thrombomodulin. RNA was extracted from frozen tissue for amplification via reverse-transcriptase polymerase chain reaction. Normal intestinal and diverticulitis tissue was used as a control. Resection samples from 36 patients with ulcerative colitis, 38 with Crohn's disease, 38 with colonic cancer, and 32 with diverticulitis were studied by immunohistochemistry, and frozen sections from the same patients were studied by immunofluorescence. Twelve biopsy specimens of adjacent intestinal areas from six patients with inflammatory bowel disease were included in the study for reverse-transcriptase polymerase chain reaction. Soluble receptors were measured in the plasma of 52 inflammatory bowel disease patients and 52 controls. DATA SUMMARY: EPCR and thrombomodulin were expressed on the mucosal endothelium of controls, and the intensity of the signal decreased in inflammatory bowel disease patients. EPCR was expressed by dendritic-like cells in controls, which also stained positive for CD21. The EPCR/CD21 dendritic-like cells were not as commonly observed in sections from ulcerative colitis patients as they were in sections from control patients (12.0 +/- 3.6 cells per high-power field vs. 23.8 +/- 10.4 cells per high-power field, p =.03), and this decrease was less evident in sections from Crohn's disease patients. Levels of messenger RNA for EPCR paralleled protein expression. Soluble thrombomodulin and EPCR levels were both higher in patients than in controls: 41.5 vs. 26.0 ng/mL (p <.0001) and 141 vs. 130 ng/mL (p <.05), respectively. CONCLUSIONS: EPCR expression on dendritic-like cells that bear the key complement receptor CD21 suggests a role for EPCR in innate immunity. The reduced expression of thrombomodulin and EPCR in the mucosal vessels in inflammatory bowel disease impairs protein C activation, favoring microthrombosis.

Adult↗

PubMed2004

The translocation of marrow MNCs after experimental myocardial cryoinjury is proportional to the infarcted area.

BACKGROUND: The selective homing of peripherally injected marrow MNCs (MMNCs) has recently been demonstrated in a model of cryodamaged heart. However, the mechanism underlying this phenomenon is still unknown. In the hypothesis that this process is related to the necrotic area extension, the infarcted area was correlated with the number of homed MMNCs in a model of experimental cryodamaged heart. STUDY DESIGN AND METHODS: A total of 12 donor and 12 recipient inbred isogenic adult (4 weeks old) Fisher rats were used to mimic autologous transplantation. Myocardial damage was obtained in recipient rats by cryoinjury. MMNCs were purified, labeled with PKH26 (a red fluorescent cell dye), and infused 7 days after the injury through the femoral vein of recipient rats. One week after peripheral administration, the number of homed MMNCs was assessed and the infarct size was correlated with the number of cells present in the target. RESULTS: Labeled cells were found only in the injured myocardium of the treated animals (n = 6), where a mean of 12 +/- 3 PKH26+ cells per section examined were found; a significant correlation was found between the infarct size and the estimated number of cells (p = 0.008) CONCLUSION: These data indicate that the homing of MMNCs is related to the extent of the myocardial injury, suggesting that cellular therapy for regeneration of damaged myocardium should be individualized by taking into consideration the extension of the area to repair.

Animals↗

PubMed2004

Bcl-6 gene mutations in primary cutaneous B-cell lymphomas.

We analyzed mutations in the 5' non-coding region of the BCL-6 gene in 46 cases of primary cutaneous B-cell lymphomas (PCBCL), using a polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) method. The results indicate that PCBCL display a low frequency of mutations and support a marginal zone B-cell origin for most of these neoplasms.

5' Untranslated Regions↗

PubMed2003

Mutations of the 5' noncoding region of the BCL-6 gene in primary bone lymphomas.

Somatic point mutations of the 5' noncoding region of the BCL-6 gene have been described as genetic alterations in non-Hodgkin lymphomas (NHL). They are more frequent in diffuse large B cell (DLBCL) and follicular lymphomas (FL). This study aims to analyse the presence and distribution of BCL-6 gene mutations in a large series of primary bone lymphomas (PBL), a rare extranodal presentation of NHL frequently associated with diffuse large cell morphology. Fifty-three cases of PBL were examined. Mutations were detected with non-radioisotopic polymerase chain reaction-single strand conformation polymorphism and visualized with fluorescent cycle sequencing. Among stage I(E) PBL, there were 30 cases of DLBCL and one each of follicular, anaplastic large cell and peripheral T-cell lymphoma. The stage II(E) PBL included six DLBCL and one lymphoplasmacytic lymphoma, whereas within stage IV PBL there were 12 DLBCL and one Burkitt lymphoma. Fifteen patients (28%) displayed mutational events. In nine cases there were more than one BCL-6 mutation. Only DLBCL displayed mutations (31%). Mutations included single base-pair substitutions (16 transitions and ten transversions) and a single point insertion (ins A 427-28). The frequency of mutations resulted lower in DLBCL of the PBL category than in the majority of other extranodal large cell lymphomas. The prevalence of mutations was higher in stage I(E) PBL than in more advanced stages of the disease (II(E) + IV) ( p=0.02). Our results reinforce the observation of heterogeneity of the DLBCL included in the clinical category of PBL.

5' Untranslated Regions↗

PubMed2003

HER-2/Neu alterations in non-small cell lung cancer: a comprehensive evaluation by real time reverse transcription-PCR, fluorescence in situ hybridization, and immunohistochemistry.

PURPOSE: Amplification and/or overexpression of HER2/neu have been documented in many types of epithelial tumor, and HER2/neu evaluation is now gaining importance, because this mechanisms of disease can be inhibited in vivo using humanized monoclonal antibodies. The main purpose of our investigation includes the evaluation of the prevalence of HER2/neu alterations in non-small cell lung cancer (NSCLC) at different molecular levels. EXPERIMENTAL DESIGN: We performed a comprehensive investigation of HER2/neu alterations in a series of 115 NSCLC, using fluorescence in situ hybridization (FISH), real time reverse transcription (RT)-PCR, and immunohistochemistry. RESULTS: HER2/neu immunoreactivity was detected in 26 of 115 of specimens (23%), with 5 carcinomas (4%) showing intense staining. Real time RT-PCR demonstrated HER2/neu mRNA in all samples analyzed, with levels above normal in 54 of 115 of carcinomas (47%). FISH documented HER2/neu gene amplification in 9 of 41 carcinomas (22%). CONCLUSIONS: These results demonstrate that HER2/neu alterations occur in NSCLC, albeit with significantly different prevalence depending on the technical assay used for the assessment. It is therefore likely that inhibitory monoclonal antibodies will be appropriate in the treatment of a subgroup of NSCLC patients. The results suggest that other mechanisms unrelated to gene amplification could be responsible for HER2/neu mRNA or protein overexpression. FISH, real time RT-PCR, and immunohistochemistry are complementary techniques for the evaluation of HER2/neu activation, useful for the identification of the subgroup of patients to be treated. The real time RT-PCR assay is very sensitive and requires minimal amounts of tissue for testing, and additional studies should evaluate its clinical application for patient evaluation.

Adult↗

PubMed2003

Human telomerase reverse transcriptase mRNA expression assessed by real-time reverse transcription polymerase chain reaction predicts chemosensitivity in patients with ovarian carcinoma.

PURPOSE: To evaluate in vivo whether the expression of the human telomerase reverse transcriptase (hTERT) gene, the catalytic subunit of the telomerase complex, is predictive of response to chemotherapy in ovarian cancer patients. PATIENTS AND METHODS: Fifty-nine advanced-stage ovarian cancer patients who were treated with platinum-based chemotherapy were studied. hTERT levels were evaluated by real-time reverse transcriptase polymerase chain reaction (RT-PCR) on tumor specimens obtained before the treatment. Variables were analyzed by the chi(2) and Fisher's exact tests. Logistic regression analysis was also performed to account for the effects of all the covariates investigated (residual disease, stage, histotype, and grade). RESULTS: Twenty-eight (47%) of the 59 tumors showed low hTERT levels, whereas 31 (53%) tumors displayed high hTERT levels. Seventy-five percent of complete responders showed high levels of hTERT expression, whereas 66% of partial responders or nonresponders exhibited low hTERT levels (P =.002). Only residual disease and hTERT expression were independent predictors of response (odds ratios, 13.455 and 7.586, respectively). The combination of these two parameters provides powerful predictive information: 18 of the 20 patients with residual disease more than 2 cm and low hTERT levels were partial responders or nonresponders, whereas 11 of the 12 patients with residual disease less than 2 cm and high hTERT levels showed a complete response (chi(2) = 21,416; P <.00001). CONCLUSION: Our data indicate that hTERT expression, measured by real-time RT-PCR, is a possible independent marker of response to platinum-based therapy in advanced stage ovarian cancer patients. Prospective validation of this marker will be required to further define its predictive value.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2003

Survivin gene expression in early-stage non-small cell lung cancer.

Survivin is an inhibitor of apoptosis protein, overexpressed in most human malignancies and implicated in mitosis regulation and preservation of cell viability. In order to investigate the prevalence and clinical significance of survivin in early-stage non-small cell lung carcinoma (NSCLC), survivin mRNA levels and protein expression were evaluated, using quantitative real-time RT-PCR and immunohistochemistry, respectively, in a series of 83 patients with stage I (IA and IB) surgically resected NSCLC. Detectable survivin mRNA levels could be demonstrated in all non-neoplastic lung tissue samples and in the tumours analysed. Survivin mRNA levels were elevated in 80 carcinomas (96%) compared to normal lung (p = 0.008). Among all tumours, survivin transcripts were present at a higher level in squamous cell carcinomas (p = 0.0022). Cytoplasmic and nuclear immunoreactivity was found in 70% and 80% of tumours, respectively and both were present in 54%. Cytoplasmic immunoreactivity correlated with tumour stage (p = 0.019). Survivin expression levels did not correlate with patient survival. In one specimen, cytoplasmic and focal nuclear immunostaining was observed in dysplastic bronchial squamous metaplasia. These results document that survivin overexpression is almost always present in early-stage NSCLC, suggesting that this protein may play a role in lung tumourigenesis. This ubiquitous expression makes survivin an appealing new target for novel therapies in lung cancer. In addition, this study also documents that survivin overexpression could be exploited for diagnostic purposes and that quantitative real-time RT-PCR can be a useful tool for evaluating survivin activation in NSCLC.

Adult↗

PubMed2003

Molecular and immunohistochemical analysis of HER2/neu oncogene in synovial sarcoma.

Amplification and/or overexpression of HER2/neu have been documented in many types of epithelial tumor and recently has been reported in sarcomas, particularly in osteosarcomas. But the role of HER2/neu alterations in soft tissue tumors remains poorly understood. Thus the present study investigates the expression of HER2/neu in 13 patients with synovial sarcoma (SS). In this study, HER2/neu mRNA levels were measured in frozen tissue samples using a real-time reverse transcription-polymerase chain reaction assay; protein expression was assessed by immunohistochemistry using an anti-HER2/neu polyclonal antibody. Six normal skeletal muscle specimens were used to establish basal levels of HER2/neu mRNA. HER2/neu transcripts were detected in all normal tissues and SSs. Four of 13 sarcomas (31%) demonstrated HER2/neu mRNA levels above the mean value, whereas 3 tumors (23%) displayed HER2/neu protein overexpression. Both membranous and cytoplasmic patterns of immunostaining were observed, and a strong correlation was found between protein expression and mRNA level (P = 0.01). Increased HER2/neu mRNA levels were significantly associated with a lower risk of developing recurrences (P = 0.02). Moreover, none of the patients with HER2/neu overexpression developed metastasis. Our data demonstrate that HER2/neu is expressed in SSs and that both membrane and cytoplasmic HER2/neu expression correlate with mRNA levels. Our results show that the presence of increased levels of HER2/neu in SSs is associated with a more favorable clinical course. Further studies are needed to assess the role of this oncogene in SSs and to evaluate the application of inhibitory humanized monoclonal antibodies in the treatment regimens for this malignancy.

Adolescent↗

PubMed2003

High incidence of benign testicular neoplasms diagnosed by ultrasound.

PURPOSE: We evaluated the clinical and histological significance of incidental ultrasonographic focal testicular lesions and assessed whether a conservative surgical approach may put the patient at higher oncological risk due to insufficient surgical eradication. MATERIALS AND METHODS: From October 2000 to May 2002 all patients with infertility, scrotal swelling, scrotal pain, varicocele, scrotal trauma or erectile dysfunction underwent scrotal ultrasonography. A total of 1,320 patients were investigated. Focal testicular lesions were found in 27 patients (2%), palpable nodules were present in 17 (63%) and nonpalpable incidental lesions were diagnosed in 10. Nodule diameter was 3 to 24 mm. All patients underwent explorative surgery via inguinotomy and preventive clamping of the spermatic cord. The nodules were completely removed with biopsy of the resection margins. Nonpalpable lesions were removed under ultrasonographic guidance. The testicle was only preserved when frozen section revealed a benign lesion and margins were negative. RESULTS: Of the 17 cases of palpable lesions (diameter 3 to 24 mm) conservative surgery was performed in 8 (47%). Definitive histological diagnosis showed Leydig cell tumor in 2 (25%), and large cell calcifying Sertoli's cell tumor, adenomatoid tumor, pseudofibrotic tumor of the tunica albuginea, epidermoid cyst, tubular fibrosis and non-Hodgkin's lymphoma in each 1 (12.5%). The remaining 9 patients (53%) underwent orchidectomy. Definitive histological examination revealed pure seminoma in 4 patients (44%), embryonal carcinoma in 4 (44%) and diffuse Leydig cell hyperplasia in 1 (12%). Seven of the 10 pts (70%) with nonpalpable nodules (diameter 4 to 16 mm) underwent conservative surgery. Histological study revealed focal Leydig cell hyperplasia in 1 case (10%), fibrosis in 3 (30%), infarction in 2 (20%) and mesothelial hyperplasia in 1 (10%). Orchiectomy was performed in the remaining 3 pts. Histology showed diffuse Leydig cell tumor in 2 pts (20%) and adenomatoid tumor with abscessed areas in 1 (10%). Neither atrophy nor local relapse was observed in pts who underwent conservative treatment during followup (mean: 1 month, range 19 to 9). CONCLUSIONS: The incidental diagnosis of testicular ultrasound alterations is increasing and 80% show a benign histology. In these cases a conservative surgical approach is the best option and it does not expose the patient to the risk of relapse.

Abscess↗

PubMed2003

Homing of peripherally injected bone marrow cells in rat after experimental myocardial injury.

BACKGROUND AND OBJECTIVES: Significant progress has been achieved during the past 10 years in cell transplantation and recent research has focused on the possibility of improving ventricular function after myocardial infarction. Most studies in the field of cardiac tissue repair are performed by direct intramyocardial injection of cells of different origin. Since this approach requires a surgical intervention, in this study we investigated the feasibility of non-invasive administration of bone marrow mononuclear cells (BMMNCs) by assessing the fate of peripherally injected, purified, labeled cells in cryodamaged hearts. DESIGN AND METHODS: Ten donor and ten recipient inbred isogenic adult (4 weeks old) Fisher rats were used as models to mimic autologous transplantation. Myocardial damage was obtained in recipient rats by placing a frozen metal probe on the anterior left ventricular wall for 15 seconds (freeze-thaw injury technique). BMMNCs were purified and labeled with a red fluorescent cell dye. Seven days after the injury about 15-25x10(6) cells were infused through the femoral vein of recipient rats. Seven days after the infusion, the heart, lungs, liver, kidneys, spleen and thymus were harvested to track transplanted cells. RESULTS: Labeled cells were found only in the injured area of the heart and not in the normal tissue, and a limited number of cells were identified in the spleen of all the animals. Most of the labeled cells in the infarcted area were Thy-1(+) and some were CD34(+). INTERPRETATION AND CONCLUSIONS: Our data suggest that peripherally injected BMMNCs can traffic through the circulation to the site of damage; we hypothesize that tissue injury leads to the priming of a cytokine cascade acting as chemoattractant for the infused cells.

Animals↗

PubMed2003

A rare case of benign fibroepithelial tumor of the seminal vesicle.

Primary tumors of seminal vesicles are rare. We report on a benign tumor of the seminal vesicle with fibroepithelial and cystic features. We performed a laparoscopic transperitoneal approach. The mass, not fixed to any anatomical structures except to the prostate, was isolated and removed. Histological examination of tumor revealed two distinct components: epithelial and stromal. We consider the term fibroadenoma more appropriate than cystoadenoma, because the stroma is not reactive but a distinct neoplastic component.

Genital Neoplasms, Male↗

PubMed2002

Malakoplakia of the pancreas with diffuse lymph-node involvement.

We report a case of malakoplakia involving the pancreas in a 74-year-old man with associated regional lymphoadenopathy. Histological examination of both pancreas and lymph nodes revealed a diffuse histiocytic infiltrate containing numerous Michaelis-Gutmann bodies. Electron microscopy supported the diagnosis of malakoplakia and showed bacterial-like structures. Differential diagnosis includes myofibroblastic inflammatory tumor and histiocytic neoplasms. Lymph-node involvement during malakoplakia is extremely rare and it has never been documented microscopically. Lymphohematogenous spread of bacteria may be the cause of the nodal involvement, which, however, does not appear to influence the clinical course of the disease.

Aged↗

PubMed2002

Prediction of survival in stage I lung carcinoma patients by telomerase function evaluation.

Telomerase activity and telomerase reverse transcriptase (hTERT) expression are elevated in human malignancies. We have investigated telomerase activity measured by the telomeric repeat amplification protocol (TRAP) assay and hTERT levels by real-time RT-PCR in stage I non-small-cell lung carcinomas. The purposes of our study included the comparison of these two techniques in the assessment of telomerase function and the evaluation of their prognostic significance. Telomerase activity and hTERT levels were determined in 90 stage I non-small-cell lung carcinoma patients, using TRAP assay and real-time RT-PCR, respectively. Variables were analyzed by the chi(2) and Fisher exact tests. Survival was analyzed by the Kaplan-Meier method. Multivariate analysis was performed with the Cox's proportional hazards model. Telomerase activity was elevated in 60 (67%) carcinomas. hTERT was elevated in 43 (48%) carcinomas. Only 21 (23%) tumors had low telomerase function by both TRAP and hTERT expression levels. Telomerase activity and hTERT were significantly correlated (p = 0.017), although 35 cases displayed discordant results. Both telomerase activity and hTERT levels were significantly associated with poor patient overall and disease-free survival (p = 0.019 and p = 0.018 for TRAP, and p = 0.011 and p = 0.012 for hTERT, respectively). Among the 21 patients with tumors displaying low telomerase function, defined by both TRAP and hTERT expression levels, only one succumbed to the disease (p = 0.0053). Our results suggest that the two techniques used in this study evaluate separate aspects of telomerase function and their combination provides powerful prognostic information in lung cancer patients.

Adult↗

PubMed2002

Lymphomas of the bone: a pathological and clinical study of 54 cases.

We examined 28 cases of primary bone lymphomas (PBL; stage IE) and 26 cases of systemic lymphomas involving the bone (SBL; stage IIE to IV). Two histologic types were prevalent: Diffuse large B-cell lymphomas (DLBCL; 26 PBL and 21 SBL) and CD30+ anaplastic large cell lymphomas (ALCL; 1 PBL and 4 SBL). A mature B phenotype (CD45+, CD20+, CD79a+, CDw75+/-, CD10-/+) was established in the DLBCL group. Bcl-2 immunoreactivity was demonstrated in 13/37 cases (35%), and bcl-6 immunostaining was observed in 22/32 cases (69%). ALCL showed null/T phenotype (CD3-/+; CD43+/-; CD30+), with ALK-1 expression in 3/3 cases. With use of a FR3A primer, a monoclonal pattern was demonstrated by PCR analysis in 22/41 lymphomas (54%). Bcl-2 translocation was identified in 2/41 cases (5%). This study details the clinical and pathological characteristics of bone lymphomas. Our immunohistochemical and molecular data suggest that most of them are "de novo" DLBCL and support their follicle center origin.

Adolescent↗

PubMed2002

[Pathology and physiopathology of urethral stenosis].

The research of new techniques for surgical repair of urethral stenosis, has developed interest and knowledge toward tissue handling and transfer in urology. Successful surgical repair of "long" stenosis is possible nowadays, using graft or flap tissue transfer. The knowledge of methral anatomy and of histopathology urethral anatomy, histopathology and physiopathology of the mechanism involved in process of urethral narrowing, is necessary for the diagnosis and the surgical indication of this pathology. To review physiopatological and anatomopathological aspects of urethral stenosis is the aim of the authors.

Humans↗