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V D'Alessandro

Publications and source records attributed to V D'Alessandro.

34 records · Page 2Linked to original sources
PubMedDate not supplied

Internalization and release of insulin from hepatocytes.

Degradation of internalized insulin was studied after binding at 25 degrees C and 37 degrees C to isolated hepatocytes. The cells were washed to avoid extracellular insulin contamination. Degradation of both, intracellular and extracellular 125I-insulin, was measured with TCA and insulin antibody. In these conditions binding at 25 degrees C and 37 degrees C was equal but both intra and extracellular degradation were greater at 37 degrees C than at 25 degrees C. At both temperatures, intracellular degradation was greater than extracellular degradation with accumulation of degraded and non-degraded intracellular insulin. To study in what state hepatocytes release internalized insulin into the medium, 125I-insulin association was performed at an intermediate temperature (30 degrees C). Extracellular insulin contamination (whether associated or not) was avoided by three methods: 1) washing; 2) treatment with insulin degrading enzyme(s) and washing; 3) treatment with insulin degrading enzyme(s) then with trypsin and washing. Kinetics of radioactivity released from the cells was identical in the three conditions and the radioactivity was released throughout the experiments. Complete degradation of the released insulin was observed by gel filtration when the previous binding was 0.4 ng insulin/10(6) cells. When the dose of associated insulin increased (25 ng/10(6) cells) 3.5% of non-degraded insulin was liberated and when the dose was 14,300 ng/10(6) cells, the insulin released was 44.3%. In one experiment during the first 30 min, the insulin released was 52.88% and in the last 45 min 39.59%. To study the biologic behavior of the insulin released from cells, a group of mice were injected with this insulin (8.4 mU/mouse) and blood glucose was measured. The released insulin behaved as intact insulin as far as blood glucose responses were concerned. We may conclude that liver cells have the ability to internalize insulin and release biologically active insulin after accumulation.

Animals↗
PubMedDate not supplied

Evaluation of epidermal growth factor receptor, carcinoembryonic antigen and Lewis carbohydrate antigens in human colorectal and liver neoplasias.

The expression of LewisY related carbohydrate antigens and the content of epidermal growth factor receptor (EGF-R), the carcinoembryonic antigen (CEA) and the alpha-fetoprotein (AFP) in colorectal and liver tumors were determined. These included 30 large bowel adenocarcinomas (7 colon, 6 sigma, 5 caecum, 12 rectum), 12 hepatocellular carcinomas and 6 liver metastases. Histologically normal tissue excised along with the tumors were used as controls. All plasma membranes studied showed specific EGF binding, and tumor plasma membranes had an EGF receptor level higher than that of the normal counterpart. However, EGF-R was positive in only a few tumors, and no correlation between clinical stages and grades of differentiation was observed. Cytosol CEA was higher in tumors than in normal counterparts. Tissue AFP and CEA content was different in liver hepatocellular carcinomas and in liver metastases. They are good markers to differentiate between primary and secondary liver neoplasias. The LewisY and related carbohydrate antigens, evaluated by the reactivity of the tissues to monoclonal antibody MAb B3, are expressed in liver metastases from colorectal adenocarcinoma. MAb B3 failed to react with hepatocellular carcinomas and with peritumoral liver tissues obtained from both metastatic and primary tumor lesions. These data suggest that immunoblotting with MAb B3 may be useful to obtain more information on liver carcinomas. Furthermore, MAb B3 or CEA armed with toxin in the form of recombinant immunotoxin or linked to a radionuclide can be useful in new treatments of metastatic lesions, such as immunotherapy, radioimmunotherapy and radioimmunoguided surgery.

Adenocarcinoma↗
PubMedDate not supplied

[Dyspepsia and Helicobacter pylori].

Since Helicobacter pylori (Hp) was first isolated in 1983, much work has been carried out on the pathogenic effects of this organism. Hp infection is common in humans and currently is the most important etiologic agent in the development of chronic active gastritis, gastric and duodenal ulcers, carcinoma and Malt-lymphoma of the stomach. Moreover Hp infection has also been associated with various extradigestive diseases. At present, a role of Hp infection in dyspepsia is discussed. Dyspepsia is defined by persistence of pain, burning or discomfort localised to the upper abdomen; some authors include in dyspepsia symptoms such as belching, bloating, alitosis, nausea, postprandial repletion, vomiting and regurgitation. In absence of any underlying pathologies, such as peptic ulcer, gastroesophageal reflux, pancreatitis, biliary tract disease or others, dyspepsia is defined as functional or idiopathic dyspepsia. Functional dyspepsia may be distinct in ulcer, reflux or dysmotility-like dyspepsia and unspecified dyspepsia. Hp infection is common in dyspeptic patients and a role of this bacterium has been postulated mostly in ulcer-like dyspepsia. Mechanisms by when Hp induces dyspeptic symptoms are uncertain; bacterial cytotoxins, phlogosis mediators, activity of chronic gastritis Helicobacter-related and host immune response probably play an important role in pathogenesis of functional dyspepsia. However, dyspepsia is not present only in infected patients; therefore other pathogenic factors may be implicated in expression of dyspeptic symptoms in uninfected subjects, such as gastric dysmotility, modifications of gastric output or altered visceral sensibility, psychological factors, gastroesophageal reflux and irritable bowel.

Dyspepsia↗
PubMedDate not supplied

Stop-flow in mediastinum and thorax for resistant lymphoma.

BACKGROUND/AIMS: Management of patients with heavily pretreated malignant lymphoma failing frontline treatment and salvage high-dose chemotherapy and autologous peripheral stem cell rescue, is problematic. A pilot study was conducted to evaluate isolated thoracic perfusion of drugs by means of stopflow technique. METHODOLOGY: Six patients were enrolled in the study; diagnoses included 4 advanced Hodgkin's disease, 1 primary mediastinal B-cell lymphoma, and 1 anaplastic large cell lymphoma. Patients were aged 18-37 years; 4 presented with bulky mediastinum. They had never achieved a complete response since all had progressed from front-line treatment, and 3 had even failed salvage high-dose chemotherapy with autologous peripheral stem cell rescue. Cisplatin (100 mg/m2) and melphalan (35 mg/m2) were used. Carmustine (100 mg/m2) were added to these 2 drugs and cytarabine (2000 mg/m2) in patients not previously treated by carmustine, etoposide, cytarabine, and melphalan. Epidoxorubicin (70 mg/m2) was added in patients who previously received a suboptimal dosage of antracycline. Drugs were delivered monthly via aortic perfusion performed by means of Aigner's stop-flow technique. RESULTS: Overall 13 cycles of perfusional chemotherapy were administered with a median number of 2 cycles. During the procedures there were no technical, hemodynamic, or vascular complications, and no deaths occurred during surgery. After 1 month, 6 (100%) objective responses after isolated thoracic perfusion were recorded, 3 (50%) of which were complete. Tolerance to therapy was excellent. Hematological toxicity was mild and transfusional support was needed only in one course. At the last follow-up, 2 patients are alive (1 complete response and 1 very good partial response, maintained). CONCLUSIONS: This new therapeutical approach seems very active in recurrent/refractory malignant lymphoma and may play an important role in this setting.

Adolescent↗
PubMedDate not supplied

[Case report: Acro-necrosis of the upper limbs caused by gemcitabine therapy].

INTRODUCTION: Even if infrequent, a digital necrosis after chemotherapy can occur in cancer patients. The gemcitabine is generally well tolerate; the cutaneous toxic ulcerations only in 0.3% of the cases induces the suspension of the treatment. CLINICAL CASE: A 70 year old patient, female, with a bladder cancer, after a trans-urethral resection, is submitted to adjuvant chemotherapy with Gemcitabine 1700 mg (total dose/die), with administration in the days 1st and 8th, while in the 15th day was not effected because, to distance of 3-4 days from the second administration, appear paresthesies of the fingers of the hands, together with Raynaud type phenomenon, 38-39 degrees C intermittent fever, digital necrosis and fingertips gangrene. Laboratory: (Normal): RF; AutoAb: AMA, ASMA, APCA, anti-DNA; ENA; lupus anti-coagulant; Ab-anti-cardiolipin; C3-C4, CIC; homocysteine, anti-thrombin, protein C, protein S, mutation of the factor V of Leiden, plasminogen, alfa 2-antiplasmin. (Altered): Auto-antibody: ANA (on Hep-2): positive (title 1/160, speckled pattern), cryoglobulin positive, ESR 29; Instrumental examinations: Superior Limbs Angiograpy: Occlusion of the digital arteries proper of 2nd, 3rd and 4th finger of the hands. Electromyography Inferior Arts: normal. Superior Arts: bilateral suffering of the median nerve at the carpal tunnel. Biopsy of the hand cutis: Hyperkeratosis, acanthosis and papillomatosis of the skin. Arterial vases with signs of endothelioangiitis and aspecific inflammation. CONCLUSIONS: Even if acronecrosis of the superior limbs is a rare effect of the gemcitabine, we would recommend particular caution in the administration of this drug in patient with known autoimmune disorders.

Aged↗
PubMedDate not supplied

Pelvic recurrence following resection of rectal cancer: a multivariate predictive model.

Local recurrence of rectal cancer (LR) after "curative" surgery is a major clinical problem, with a low resectability rate and a dismal prognosis. Prediction of LR might permit more targeted postoperative surveillance with earlier diagnosis of recurrent disease and might help in selecting the patients to be assigned to the most suitable adjuvant treatment protocol. To evaluate if a simple multivariate model could predict the LR and survival probability in the single case, we retrospectively evaluated 118 consecutive patients (63 males, 55 females; mean age 62 +/- 12 years) operated on for rectal cancer and followed up for a minimum of 4 years (range 51-111 months). Local recurrence rate was 28%, with a 6% of local + distant failure. Age and sex of patients, type of surgery, location of tumour in the rectum, size, morphology and grading of the tumour were all unrelated to the event under investigation. At Cox regression, the Dukes' stage and the postoperative radiotherapy were the only independent prognostic factors for LR (p < 0.001). The multivariate model was able to correctly reclassify the patients and predict local recurrence in 86.2% of the cases. Prevention of LR by adequate surgery and adjuvant therapy as well as its early detection offer the best prospect of improving the results of surgery for rectal cancer.

Adenocarcinoma↗