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Biomedical subjects

G Valente

Publications and source records attributed to G Valente.

At least 37 records · Page 2Linked to original sources
PubMed1999

Small cell carcinoma of the esophagus.

Small cell carcinoma of the esophagus (SCEC) is a rare tumor with its particular biologic features, distinct from squamous and glandular carcinoma of esophagus. Although initial symptoms can be similar (with metastatic dissemination and paraneoplastic syndromes at presentation more frequent in SCEC), differences in age and sex distribution, tumor location, radiological and endoscopic findings, clinical course and prognosis have been observed between SCEC and other esophageal malignancies. SCEC should be considered a systemic disease, and by analogy to bronchogenic small cell carcinoma, multimodality approach including chemotherapy is recommended. In patients with limited disease, irradiation or surgery should be offered after induction chemotherapy to manage local disease. However, optimal treatment schedule has not yet been defined. In the future, registration of all SCEC cases and careful analysis of prognostic factors in the larger multi-institutional series could contribute to further progress in treatment outcome.

Carcinoma, Small Cell↗
PubMed1999

RR interval variation, sympathetic skin reflex and QT dispersion in the assessment of autonomic function in peripheral neuropathy.

In recent years, two simple non-invasive tests, sympathetic skin response (SSR) and RR interval variation (RRIV) have been used to assess autonomic function (Wang et al., 1994; Drory et al., 1995; Chassande et al., 1996; Bordet et al., 1996; Spitzer et al., 1997). Their easy performance by an electromyographic (EMG) machine and successful clinical correlation (Shahani et al., 1990) have made them routine in autonomic assessment in several EMG laboratories. More recently QT dispersion on electrocardiogram (ECG) has been shown to have increased in patients with diabetic neuropathy and several autonomic dysfunctions (Wei et al., 1995; Lengyel et al., 1997; Langen et al., 1997; Axelrod et al., 1997). In order to evaluate the diagnostic value of the RR interval variation, sympathetic skin response and QT dispersion combined, we performed the three tests on a group of 37 patients with several peripheral neuropathies with and without clinical signs of dysautonomia. All patients were studied using an electromyograph (EMG). The results of the SSR, RRIV and QT dispersion combined have shown abnormal values in all patients with neuropathy and clinical dysautonomia and in some patients without clinical signs of dysautonomia, suggesting a subclinical autonomic dysfunction. The principal finding of this study is that the evaluation of the RRIV, SSR and QT dispersion combined may contribute to the assessment of dysautonomia in patients with somatic neuropathy and that they may be currently performed by an electromyograph.

Adult↗
PubMed1999

[Tumors of the parapharyngeal space: case report of clear cell myoepithelioma of the parotid gland and review of literature].

The parapharyngeal space is a deep neck region and can be the site of a wide range of neoplasms, including primary benign or malignant tumors, metastatic tumors, neoplasms invading the parapharyngeal space from the adjacent regions and neoformations stemming from systemic processes. Tumors of the parapharyngeal space are, nevertheless, relatively rare and account for 0.5-0.8% of all head and neck tumors. Most are benign tumors originating in the deep lobe of the parotid gland and the minor salivary glands. The most frequent tumor is pleomorphic adenoma while myoepithelioma accounts for just 1% of all salivary gland tumors. The present case report involves a case of myoepithelioma of the deep parotid gland lobe, arising in the parapharyngeal space. Together with a review of the literature, considerations are presented on the clinical and radiological evaluation, differential diagnosis and treatment of these lesions.

Aged↗
PubMed1998

The murine homolog of the HIN 200 family, Ifi 204, is constitutively expressed in myeloid cells and selectively induced in the monocyte/macrophage lineage.

To examine the expression of Ifi 200 genes in vivo and add new information about their function, polyclonal monospecific rabbit antibodies, designated N-term or C-term, were raised against both the N-terminus and C-terminus of the 204 protein (p204) respectively. Western blotting analysis demonstrated that p204 and D3, another member of the Ifi 200 gene family, are constitutively expressed, though at different degrees, in bone marrow, thymus and lymph nodes, and barely detectable in the spleen. Poly rI:rC treatment did not modulate their expression. Peritoneal resident macrophages (Mphi) from untreated mice were negative, but displayed high levels of both p204 and D3 on poly rI:rC treatment. A significant increase of these proteins is also observed when Mphi are cultured overnight in vitro with IFNs or LPS. Lung, kidney and brain were negative for p204 and D3 expression. These results, together with immunohistochemical analysis, demonstrate that the 204 gene has an expression pattern restricted to cells of the myelomonocytic lineage similar to that observed for the human homolog, the myeloid nuclear differentiation antigen (MNDA) suggesting its potential involvement in the differentiation and maturation of this cell lineage.

Animals↗
PubMed1998

Human herpesvirus type 7 in Hodgkin's disease.

Several lines of evidence have pointed to the involvement of a viral agent in the pathogenesis of Hodgkin's disease (HD). Therefore we investigated the presence of human herpesvirus type 7 (HHV-7) in 53 cases of HD by polymerase chain reaction (PCR), DNA in situ hybridization (ISH) and immunohistochemistry. HHV-7 DNA was frequently detected (68% of the cases) in HD biopsies by PCR independently of the histological type, whereas only 32% (P<0.05) of positive cases were found in 19 reactive lymph nodes. However, by applying the quantitative PCR technique, the majority of the samples showed a low level of viral load. Moreover, ISH for HHV-7 DNA was positive in a low number of small T lymphocytes and consistently negative in Hodgkin and Reed-Sternberg (HRS) cells, which appeared negative for HHV-7 also at immunohistochemistry. These results indicate that the high frequency of HHV-7 infection in HD: (i) is probably non-productive, (ii) mainly involves small lymphocytes belonging to the T-lineage, and (iii) is probably due to the recruitment of non-malignant reactive cells in HD tissue.

DNA, Viral↗
PubMed1998

[Laryngeal myoblastoma in childhood].

Laryngeal tumors originating in the nerves are extremely rare, particularly in infants. Indeed, this type of neoplasm normally arises in adult males. Only 10 cases have been described in the 5 to 17 year age range. The present work reports a clinical case of granulous tumor of the larynx in an 11-year-old boy. Histologically this tumor showed cells which preserved their original structure and were in close relation with the nerve fibers, but not with the myocytes. Their metabolic activity was similar to that of the nerve cells. The neurogenic origin of the neoplastic granulous cells shows the presence of neuroectodermic cytoplasmic S-100 specific for cells derived from the neural crest. The boy manifested ingravescent dyspnea due to the presence of a myoblastoma in the right laryngeal ventricle. A thyrotomic approach was adopted because of the significant size of the neoplasm although it was possible to perform conservative surgery given that the lesion was benign. The authors underline the polymorphic histology of this neoplasm and the importance of the type of surgery which should both avoid widespread demolition since the neoplasm is benign and, at the same time, prevent recurrences.

Child↗
PubMed1997

Growth stimulation of colorectal carcinoma cells via the c-kit receptor is inhibited by TGF-beta 1.

Activation of the receptor tyrosine kinase c-kit by the kit-ligand, also known as stem cell factor (SCF), is essential to melanocyte and germ cell development and during the early stages of hematopoiesis. Deregulated expression of c-kit has been reported in malignancies affecting these lineages, i.e., myeloid leukemias, melanomas, and germ cell tumors. In addition, c-kit and SCF are coexpressed in some breast and colorectal cancer (CRC) cells, raising the question of whether c-kit serves an autocrine role in normal or malignant epithelial tissues. In this study, we demonstrate that human colorectal carcinomas, but not normal colorectal mucosa cells, coexpress SCF and c-kit in situ. Expression of c-kit was also observed in mucosa adjacent to colorectal tumor tissue. Consistent with a growth-regulatory role of SCF in CRC cells, exogenous SCF stimulated anchorage-dependent and anchorage-independent growth in four out of five CRC cell lines. Exogenous transforming growth factor (TGF)-beta 1 added at nanomolar concentrations to HT-29 CRC cells, which express the type I, II, and III TGF-beta receptors, downregulated c-kit expression to background levels and inhibited c-kit-dependent proliferation. Similarly, TGF-beta 1 inhibited SCF-dependent proliferation of three first-passage CRC cell lines. In summary, expression of the potential autocrine SCF/ c-kit axis is a tumor-associated phenomenon in colorectal cancer that can be suppressed by TGF-beta 1 in TGF-beta-responsive CRC cells.

Adult↗
PubMed1997

Detection of MET oncogene/hepatocyte growth factor receptor in lymph node metastases from head and neck squamous cell carcinomas.

The c-MET oncogene encodes the receptor for hepatocyte growth factor/scatter factor (HGF/SF), which is known to stimulate the invasive growth of epithelial cells cultured in vitro. The Met/HGF receptor is a heterodimeric transmembrane tyrosine kinase, which is a prototype for a new family of growth factor receptors. The c-MET oncogene is expressed in several types of epithelial tissue including keratinocytes and is over-expressed in a number of human carcinomas. Studies on various carcinoma cell lines have shown that over-expression and structural alteration of the receptor result in its activation and confer tumorigenesis. We have studied Met/HGF receptor expression in tissue specimens from 34 patients with head and neck squamous cell carcinomas (HNSCC) and in 17 regional lymph node metastases. Western blot analysis was employed, using monoclonal antibodies directed against either the intracellular or extracellular domain of the receptor. Each sample was compared to its normal counterpart. The receptor did not show any major structural alterations in HNSCC tissues, but its expression was increased from 2- to 50-fold in about 70% of tumors. Immunohistochemistry then showed that the same antibodies stained only a few cells in the basal layer of normal squamous epithelium but intensely marked tumor cells. In the lymph node metastases of Met-positive tumors, receptor expression was maintained and sometimes increased with respect to primary tumors. Immunohistochemical analysis of the metastatic lymph nodes showed that cells were negative in the normal lymphatic tissue and strongly stained in tumor cells. Over-expression of the Met/HGF receptor was found at all tumor stages but was more significant in those associated with enlarged or multiple (N2-N3) lymph node metastases. These data show that expression of the Met/HGF receptor may be involved in the progression of HNSCC towards a metastatic phenotype and may be a useful marker of head and neck tumor cell spread to regional lymph nodes.

Adult↗
PubMed1997

An atypical verrucous carcinoma of the tongue arising in a patient with oral lichen planus associated with hepatitis C virus infection.

Recently, a clinical relationship between oral lichen planus (OLP) and hepatitis C virus (HCV) infection has been suggested, but the role of this virus on the course of OLP is unknown. We report an unusual lingual localisation of verrucous carcinoma arising in a patient with histologically confirmed OLP and HCV infection diagnosed with second generation enzyme-linked immunosorbent assay and recombinant immunoblot assay. Serum HCV-RNA detected using nested reverse transcriptase polymerase chain reaction (RT-PCR) confirm HCV replication. No classical risk factors associated with verrucous carcinoma were present.

Aged↗
PubMed1997

Parosteal osteosarcoma of the maxilla.

We describe the case of a 47-year-old female who presented with a small nodule in the buccal sulcus in the left maxillary incisor region. Clinical and radiographic examination revealed a small sclerotic neoplasm with a short pedicle. Histopathological examination confirmed a diagnosis of parosteal osteosarcoma. The contribution of CT to the diagnosis and management is discussed.

Female↗
PubMed1997

[Role of hyperbaric oxygen in the treatment of necrotizing infections of the soft tissues].

The Authors report their experience in the treatment of soft tissue necrotizing infections. The correct "timing" of the association of surgery, antibiotics and hyperbaric oxygen therapy is stressed. The good clinical results obtained in the patients examined confirm the usefulness of an early treatment modulated according to the needs of each single patient.

Anti-Bacterial Agents↗
PubMed1997

[Identification of clinical, biological and prognostic factors in recurring squamous cell carcinoma of the head and neck].

Many studies have been performed to determine some prognostic factors for malignant head and neck tumors. Defining the clinical and biological features would enable one to predict the progression of the disease and plan treatment. The aim of the present study has been to identify what host and neoplasm characteristics provide prognostic indication of possible recurrences. A group of 380 patients with squamous cell carcinoma of the head and neck was studied. The neoplasm was located in the following sites: 257 larynx-hypopharynx, 69 oropharynx, 54 oral cavity. At the present time 309 of these subjects are still alive and disease free while 71 have had recurrences. Analyses were performed on various variables regarding the patient, neoplasm and histology. Multivariante analysis of these prognostic factors was performed using the PLR-BMDP program. The time of recurrence in the primary tumor site and at the lymph node level was evaluated using the Kaplan-Meier method. Of the 28 variables analyzed 16 had no effect on the probability of recurrence. Two variables reduced the risk of recurrence: age over 61 years (p < 0.05) and primarily intra and peritumoral lymphocyte infiltration (p = 0.06). Of the data regarding the patient, age lower than 61 years and presence of associated internal pathologies (i.e. bronchial pneumonia and hepatitis) appeared to significantly facilitate the appearance of recurrence. The characteristics of the neoplasm which appear to effect recurrences are: tumor site (hypopharynx), presence of lymph node metastases, morphological elements of tissue spread (vascular invasion, plasmocyte infiltration), capsular breakdown, positive margins and post-operative infection. In conclusion, it can be asserted that technical development of multifactorial analysis has made it possible to identify important prognostic factors and quantify their impact on the evolution of a neoplasm.

Adult↗
PubMed1996

Histological changes in edentulous oral mucosa under implant-supported overdentures.

The microscopic characteristics of the mucosa covering the alveolar ridge that supports a complete denture have long been studied. In this paper, any histological changes in mucosa loaded by a denture before and after a denture has been anchored by implant onto the bone were followed. The results suggest that mechanical loads improve trophism of mucosa, and that fixing a denture to implants leads to a more uniform distribution of loads.

Aged↗
PubMed1996

Treatment of oral cavity and oropharynx squamous cell carcinoma with perilymphatic interleukin-2: clinical and pathologic correlations.

We describe the correlations between the clinical and histologic findings in an initial series of 60 patients with T2-4, N0-3, M0 squamous cell carcinoma (SCC) of the oral cavity or oropharynx enrolled in a randomized trial set up to evaluate whether the disease-free interval and survival are extended when perilymphatic injections of recombinant interleukin-2 (rIL-2) are combined with routine surgery and radiotherapy. Twenty-nine patients were operated on only (controls). The other 31 received two daily injections of 2,500 U rIL-2, one near the mastoid process on the same side as the tumor and the other under the chin, for 10 days before surgery, and further injections on the nonoperated-on side on a monthly basis for 1 year starting 4 weeks after surgery (or radiotherapy, where necessary) in an effort to upregulate the immune system and delay recurrence. Their surgical specimens displayed a significantly greater inflammatory reaction, larger areas of necrosis, and more intense sclerosis. The inflammatory tumor infiltration consisted of eosinophils, plasma cells, and CD25+ and human leukocyte antigen (HLA)-DR+ lymphocytes. However, no correlations were apparent with regard to the intensity of necrosis, eosinophil infiltration, and the number of DR+ cells and the clinical outcome. By contrast, the correlation between CD25+ cells and a significantly longer disease-free survival suggests that induction of T-cell reactivity, and perhaps specific immunity, is the only important aspect of rIL-2-induced antitumor reactivity.

Adult↗