PubMed Health⌕ Search

Biomedical subjects

F Belli

Publications and source records attributed to F Belli.

At least 19 recordsLinked to original sources
PubMed2006

Polyketone polymer: a new support for direct enzyme immobilization.

Polyketone polymer -[-CO-CH(2)-CH(2)-](n)-, obtained by copolymerization of ethene and carbon monoxide, is utilized for immobilization of three different enzymes, one peroxidase from horseradish (HRP) and two amine oxidases, from bovine serum (BSAO) and lentil seedlings (LSAO). The easy immobilization procedure is carried out in diluted buffer, at pH 7.0 and 3 degrees C, gently mixing the proteins with the polymer. No bifunctional reagents and spacer arms are required for the immobilization, which occurs exclusively via a large number of hydrogen bonds between the carbonyl groups of the polymer and the -NH groups of the polypeptidic chain. Experiments demonstrate a high linking capacity of polymer for BSAO and an extraordinary strong linkage for LSAO. Moreover, activity measurements demonstrate that immobilized LSAO totally retains the catalytic characteristics of the free enzyme, where only a limited increase of K(M) value is observed. Finally, the HRP-activated polymer is successfully used as active packed bed of an enzymatic reactor for continuous flow conversion and flow injection analysis of hydrogen peroxide containing solutions.

Biotechnology↗
PubMed2005

Epirubicin, cisplatin and docetaxel combination therapy for metastatic gastric cancer.

BACKGROUND: Docetaxel is a new agent with activity in metastatic gastric cancer. This phase II study was designed to evaluate the activity and safety of an epirubicin, cisplatin and docetaxel combination in patients with this disease. PATIENTS AND METHODS: Forty-six patients with gastric adenocarcinoma with measurable distant metastasis were eligible for the study. Patients received epirubicin 50 mg/m(2) and docetaxel 60 mg/m(2), on day 1, and cisplatin 60 mg/m(2) on day 2. Granulocyte colony-stimulating factor 300 mug/day subcutaneously was given on days 5 and 6. Cycles were repeated every 3 weeks for a maximum of eight courses. RESULTS: All patients were evaluable for response and toxicity. Two complete and 21 partial responses were observed, with an overall response rate of 50% [95% confidence interval (CI) 36% to 64%]. Stable disease was observed in 13 patients (28%) and progressive disease in 10 patients (22%). The median time to progression was 6 months (95% CI 5-7) and the median overall survival was 11.2 months (95% CI 8.5-13.9). Grade 3/4 neutropenia, thrombocytopenia and anemia occurred in 46%, 7% and 13% of patients, respectively. There were five episodes of febrile neutropenia in four patients. Other grade 3 toxicities included mucositis in three patients (6.5%), vomiting in four patients (8.7%) and diarrhea in one patient (2%). There were no cardiac toxicity, severe neurotoxicity or treatment-related deaths. CONCLUSIONS: The epirubicin, cisplatin and docetaxel combination is an active and well tolerated novel chemotherapy regimen for treating metastatic gastric cancer and deserves further evaluation in randomized studies.

Adenocarcinoma↗
PubMed2004

The biological functions of polyamine oxidation products by amine oxidases: perspectives of clinical applications.

The polyamines spermine, spermidine and putrescine are ubiquitous cell components. If they accumulate excessively within the cells, due either to very high extracellular concentrations or to deregulation of the systems which control polyamine homeostasis, they can induce toxic effects. These molecules are substrates of a class of enzymes that includes monoamine oxidases, diamine oxidases, polyamine oxidases and copper containing amine oxidases. Polyamine concentrations are high in growing tissues such as tumors. Amine oxidases are important because they contribute to regulate levels of mono- and polyamines. These enzymes catalyze the oxidative deamination of biogenic amines and polyamines to generate the reaction products H2O2 and aldehyde(s) that are able to induce cell death in several cultured human tumor cell lines. H2O2 generated by the oxidation reaction is able to cross the inner membrane of mitochondria and directly interact with endogenous molecules and structures, inducing an intense oxidative stress. Since amine oxidases are involved in many crucial physiopathological processes, investigations on their involvement in human diseases offer great opportunities to enter novel classes of therapeutic agents.

Animals↗
PubMed2004

The ALTEA/ALTEINO projects: studying functional effects of microgravity and cosmic radiation.

The ALTEA project investigates the risks of functional brain damage induced by particle radiation in space. A modular facility (the ALTEA facility) is being implemented and will be operated in the International Space Station (ISS) to record electrophysiological and behavioral descriptors of brain function and to monitor their time dynamics and correlation with particles and space environment. The focus of the program will be on abnormal visual perceptions (often reported as "light flashes" by astronauts) and the impact on retinal and brain visual structures of particle in microgravity conditions. The facility will be made available to the international scientific community for human neurophysiological, electrophysiological and psychophysics experiments, studies on particle fluxes, and dosimetry. A precursor of ALTEA (the 'Alteino' project) helps set the experimental baseline for the ALTEA experiments, while providing novel information on the radiation environment onboard the ISS and on the brain electrophysiology of the astronauts during orbital flights. Alteino was flown to the ISS on the Soyuz TM34 as part of mission Marco Polo. Controlled ground experiments using mice and accelerator beams complete the experimental strategy of ALTEA. We present here the status of progress of the ALTEA project and preliminary results of the Alteino study on brain dynamics, particle fluxes and abnormal visual perceptions.

Brain↗
PubMed2004

Effects of heavy ions on visual function and electrophysiology of rodents: the ALTEA-MICE project.

ALTEA-MICE will supplement the ALTEA project on astronauts and provide information on the functional visual impairment possibly induced by heavy ions during prolonged operations in microgravity. Goals of ALTEA-MICE are: (1) to investigate the effects of heavy ions on the visual system of normal and mutant mice with retinal defects; (2) to define reliable experimental conditions for space research; and (3) to develop animal models to study the physiological consequences of space travels on humans. Remotely controlled mouse setup, applied electrophysiological recording methods, remote particle monitoring, and experimental procedures were developed and tested. The project has proved feasible under laboratory-controlled conditions comparable in important aspects to those of astronauts' exposure to particle in space. Experiments are performed at the Brookhaven National Laboratories [BNL] (Upton, NY, USA) and the Gesellschaft für Schwerionenforschung mbH [GSI]/Biophysik (Darmstadt, FRG) to identify possible electrophysiological changes and/or activation of protective mechanisms in response to pulsed radiation. Offline data analyses are in progress and observations are still anecdotal. Electrophysiological changes after pulsed radiation are within the limits of spontaneous variability under anesthesia, with only indirect evidence of possible retinal/cortical responses. Immunostaining showed changes (e.g. increased expression of FGF2 protein in the outer nuclear layer) suggesting a retinal stress reaction to high-energy particles of potential relevance in space.

Animals↗
PubMed2002

Two novel genetic lesions and a common BH4-responsive mutation of the PAH gene in Italian patients with hyperphenylalaninemia.

Hyperphenylalaninemia (HPA), due to a deficiency of phenylalanine hydroxylase (PAH) enzyme, is caused by mutations in the PAH gene. Molecular analysis in 23 Italian patients with PAH deficiency identified two novel (P281R, L287V) and 20 previously described genetic lesions in the PAH gene. The detection of the A403V amino acid substitution in combination with null mutations in patients with BH4-responsive PAH deficiency leads us to correlate it with BH4 responsiveness.

DNA Mutational Analysis↗
PubMed2001

Effect of long-term adjuvant therapy with interferon alpha-2a in patients with regional node metastases from cutaneous melanoma: a randomised trial.

BACKGROUND: Less than half of patients with melanoma that has spread to local draining regional lymph nodes (stage III melanoma) live with no disease for 5 years or longer after surgery. We aimed to see whether interferon alpha-2a increased survival prospects in these patients. METHODS: 444 patients from 23 centres in the WHO Melanoma Programme had complete lymphadenectomy for pathologically proven regional nodal spread of melanoma and were randomly assigned to receive either 3 MU subcutaneously of recombinant interferon alpha-2a three times a week for 3 years, or to observation alone after surgery. Patients were stratified by centre, nodes with macroscopic or microscopic melanoma, number of affected nodes, and nodal metastatic spread. Treatment was continued for 3 years or until first sign of relapse. FINDINGS: 424 patients entered the study. 5-year disease-free survival of those who had surgery plus interferon alpha-2a was 27.5% (95% CI 21.7-33.6); for those who received surgery alone, survival was 28.4% (22.5-34.6) (p=0.50). Neither Kaplan-Meier cumulative survival rates, nor multivariate analysis of survival, showed a difference between those who had surgery and interferon alpha-2a (35%, 95% CI 29-42) and those who had surgery alone (37%, 31-44). INTERPRETATION: Patients with melanoma that has spread to the local draining regional lymph nodes tolerate well 3 MU of interferon alpha-2a given subcutaneously three times a week for 3 years, but this treatment does not improve either disease-free or overall survival.

Adolescent↗
PubMed2001

Adenocarcinoma of the lower third of the rectum: metastases in lymph nodes smaller than 5 mm and occult micrometastases; preliminary results on early tumor recurrence.

BACKGROUND: The number of examined lymph nodes and metastases in lymph nodes smaller than 5 mm (small lymph nodes) are a determining factor in the stage of rectal cancer although the clinical significance of occult micrometastases is controversial. We are reporting our preliminary results on the identification and prognostic utility of metastases in small lymph nodes and occult micrometastases. METHODS: We searched small metastatic lymph nodes in 101 cases of adenocarcinoma of the lower third of the rectum. We used the manual technique to dissect mesorectal fat and occult micrometastases in the lymph nodes of 52 Dukes' A and B patients, using a pool of anticytokeratin antibodies. RESULTS: Forty-five percent of the metastatic lymph nodes were smaller than 5 mm in diameter and determined the Dukes' stage in 15 (30.6%) of 49 Dukes' C patients. Occult micrometastases were found in 21 (40.4%) patients: five recurred but vascular invasion, positive distal margin of the rectum, and positive circumferential margin of the mesorectum were present. CONCLUSIONS: Small metastatic lymph nodes, vascular invasion, positive distal margin of the rectum, and positive circumferential margin of the mesorectum were found to be more important than occult micrometastases in predicting early recurrence of rectal cancer.

Adenocarcinoma↗
PubMed2001

Adenocarcinoma of the lower third of the rectum surgically treated with a <10-MM distal clearance: preliminary results in 35 N0 patients.

BACKGROUND: Recent reports suggest that a distal clearance (DC) of 10 mm at the lower surgical margin may be considered adequate in the surgical treatment of rectal cancer, but there are no data on the possible adequacy of a < 10-mm DC in N0 patients in whom a good prognosis can otherwise be expected, that is, those with negative surgical margins and negative lymph nodes. METHODS: Between November 1991 and December 1998, 154 consecutive patients with adenocarcinoma of the lower third of the rectum had a total rectal resection with total mesorectal excision and coloendoanal anastomosis. Among 76 N0 patients, there were 35 with <10-mm DC and 41 with > or =10-mm DC. Each group was divided into two subgroups depending on whether the surgical margins were involved or not, and the rate of local recurrence in the various categories was compared. All B2 Astler-Coller stage patients in the series received postsurgical chemoradiotherapy. RESULTS: The local recurrence rate in the 35 patients with DC < 10 mm was 11.4% and that of the 41 patients with DC > or =10 mm was 7.3%. When only patients with negative surgical margins were considered, the local recurrence rate was 3.4% for those with < 10-mm DC and 5.1% for those with > or =10-mm DC. CONCLUSIONS: Our results suggest that a radical surgery with <10-mm DC followed by chemoradiotherapy may be adequate in N0 patients, provided that a careful pathologic examination of the surgical specimen excludes the presence of lymph node metastases and that the distal rectal and mesorectal resection margins fall in healthy tissue.

Adenocarcinoma↗
PubMed2001

Docetaxel in patients with anthracycline-resistant advanced breast cancer.

OBJECTIVE: To better determine docetaxel activity in patients with well-defined anthracycline-resistant breast cancer. METHODS: From October 1996, we carried out a phase II trial in 69 heavily pretreated patients with advanced breast cancer with docetaxel 100 mg/m(2) by a 1-hour infusion on day 1, with cycles repeated every 3 weeks. Patients were classified as having primary anthracycline resistance (n = 32), secondary anthracycline resistance (n = 7), anthracycline pretreatment (n = 22) or no anthracycline pretreatment (n = 8). RESULTS: Among 68 evaluable patients, we observed 6 (9%) complete responses and 27 (40%) partial responses, for an overall response rate of 49% (95% confidence interval 37-61%); the disease remained stable in 17 patients (25%). Responses according to the above subgroups were as follows: primary anthracycline resistance 41%, secondary anthracycline resistance 43%, anthracycline pretreatment 64% and no anthracycline pretreatment 43%. The median time to response, median time to progression and median overall survival were 2, 7 and 10 months, respectively. Myelosuppression was the dose-limiting toxicity, with grade 4 neutropenia occurring in 47% of the patients and neutropenic fever in 12%. G-CSF was added in the case of grade 4 febrile neutropenia; a 25% reduction in the dose of docetaxel was required in 4 patients. Other side effects were mild. CONCLUSIONS: The results of the present trial confirm the high activity of docetaxel in heavily pretreated patients with advanced breast cancer, including those with strictly defined anthracycline resistance.

Adult↗
PubMed2001

Do patients with tumor-positive sentinel nodes constitute a homogeneous group?

From January 1993 to May 2000, 1062 patients with primary cutaneous melanoma and no evidence of clinically detectable regional node metastases underwent sentinel node (SN) dissection to microscopically define the tumor status of the regional lymph nodes. A total of 1165 biopsies were performed. The SN identification rate was 89.6%. In 62.2% of the cases, only one SN was detected; 26.4% of patients had two SNs; and 11.4% had three or more SNs. Analysis of survival indicated that the tumor status of the nodes was the most important prognostic factor. Breslow's thickness had a significant impact on survival in tumors 4 mm or thicker, and ulceration dropped to a borderline-significant P value. To assess the tumor burden in positive SNs, all slides for patients at the Istituto Nazionale Tumori and S. Pio X Hospital were reviewed. Of 658 patients in this series, 90 had positive SNs. Eighteen of these patients had evidence of metastasis in other nodes. Of the remaining 72 with a single tumor-involved SN, 62% had a single metastatic deposit. Preliminary data from this study indicate that several subgroups may be identified among patients with positive nodes, but adequate analysis of survival requires a larger number of patients and a multicenter study.

Female↗
PubMed2000

T cell responses in colorectal cancer patients: evidence for class II HLA-restricted recognition of shared tumor-associated antigens.

Few cases of anti-colon cancer specific T lymphocytes have been described so far. Moreover, the majority of these effectors were generated in vitro by stimulating PBMC from patients or healthy donors with peptides that were derived from proteins expressed and/or secreted by colon cancer tissue such as CEA, Mucin or Her-2/neu. The aim of our study was to evaluate the immunogenicity of colorectal carcinomas in an autologous setting. We exploited the antigen processing and presentation capacity of dendritic cells (DC) to establish an in vitro autologous system that can bypass the need of obtaining cultured tumor cells. DC were generated from the adherent monocyte fraction of PBMC taken from stage II/III colorectal cancer patients. A single cell suspension was prepared by mechanical and enzymatic disruption of the surgical specimens immediately after resection. DC were loaded with autologous tumor lysate, obtained by repeated freezing and thawing, before being used as stimulators for autologous PBL. HLA-class II restricted T cells that recognize the autologous tumor could be generated in a proportion of patients. The fine specificity of the anti-tumor T cells indicates that differentiation as well as tumor restricted antigens are expressed in colon cancer and that these antigens can evoke a class II HLA-restricted response in an autologous setting. Altogether these findings may open a new perspective for a DC based vaccination of colon cancer patients.

Antigens, Neoplasm↗
PubMed2000

Diagnostic and interventional radiology in the post-operative period and follow-up of patients after rectal resection with coloanal anastomosis.

Surgical treatment of carcinoma of the distal third of the rectum with anal sphincter preservation is increasingly used in accredited cancer centers. This study aimed to evaluate the diagnostic usefulness of radiological investigations in the management of patients who had undergone resection with coloanal anastomosis for carcinoma of the rectum, in the immediate post-operative period, during closure of the protective colostomy and in the follow-up of symptomatic recanalized patients. A total of 175 patients who had undergone total rectal resection with end-to-side anastomosis for carcinoma of the distal third of the rectal ampulla, most of whom had received postoperative radiotherapy, were evaluated radiologically. In the postoperative period radiological investigation was ordered only for symptomatic patients to detect pathology of the anastomosis and the pouch sutures and was used direct film abdominal radiography and contrast-enhanced radiography of the rectal stump with a water-soluble radio-opaque agent. Before closure of the colostomy, 2 months after rectal excision or approximately 4 months after if postoperative radiotherapy was given, the anastomosis and pouch of all patients, even asymptomatic ones, were studied with water-soluble contrast enema to check for normal canalization. In the follow-up after recanalization radiological examinations were done to complete the study of the large intestine if the endoscopist was not able to examine it up to the cecum. Of the 175 patients examined radiologically during the postoperative period and/or subsequent follow-up, 95 showed no pathological findings. Seventy-nine patients had fistulas of the coloanal anastomosis or the pouch, 23 of which supplied a presacral collection. In the absence of severe sepsis, the only therapeutic measures were systemic antibiotics and washing of the surgical catheters to maintain efficient operation. In 2 patients in whom transanal drainage was performed radiologically the fistula was cured in 1 week. In 36 cases of cicatricial stenosis, 17 at the coloanal anastomosis and 19 at the pouch, radiological examination always detected the lesion, correctly defining its anatomical characterisitics, nature and extension. Of the 19 cases of stenosis treated radiologically, 15 recovered an adequate intestinal calibre for tients operated on, 21 cases of reccurrence were detected. Radiological examination was requested as the first investigation in only one of these cases, for a patient with subocclusion. Radiological investigations in patients who have undergone colonanal anastomosis are of read diagnostic value in the immediate post-operative period, during closure of the protective colostomy and in the follow-up of symptomatic recanalized patients.

Anal Canal↗
PubMed2000

Total rectal resection and complete mesorectum excision followed by coloendoanal anastomosis as the optimal treatment for low rectal cancer: the experience of the National Cancer Institute of Milano.

BACKGROUND: At present, abdominoperineal resection remains the most diffuse method of treatment of very low rectal cancer. Today, we can avoid this method in some patients by using a sphincter-saving procedure. METHODS: From March 1990 to January 1999, 273 consecutive total rectal resections and coloendoanal anastomoses were performed at our Institute; this study concerns 141 consecutive patients treated for a primary adenocarcinoma of the distal rectum, from 3.5 to 8 cm from the anal verge. Patient stratification, based on definitive pathological report, was 31 Dukes' stage A (T2N0), 44 stage B (T3N0), and 66 stage C (T2N+-T3N+). RESULTS: Overall recurrence rate was 9.2%; postoperative morbidity attributable to the procedure was low. A perfect continence was documented in 61% of cases. The only pathological factor related to local recurrence rate is peritumoral lymphocytic reaction inside and around the tumor (P = .0005 and .031) independently from the number of metastatic lymph nodes, depth of fatty tissue infiltration, and lymphatic and venous neoplastic emboli. The minimum follow-up time is 12 months. CONCLUSIONS: Our data, in accordance with other authors, seem to highlight the relevant role that a well-practiced surgery, together with accurate information on the spreading of this disease, has in achieving an optimal local control of cancer.

Adenocarcinoma↗
PubMed2000

Sentinel lymph node biopsy in cutaneous melanoma: the WHO Melanoma Program experience.

BACKGROUND: We report the experience of the World Health Organization (WHO) Melanoma Program concerning sentinel lymph node (SLN) biopsy for detecting patients with occult regional nodal metastases to submit to selective regional node dissection. METHODS: From February 1994 to August 1998, in 12 centers of the WHO Melanoma Program, 892 SLN biopsies were performed in 829 patients with clinical stage I melanoma (male: 370; female: 459; median age: 50 years old). The location of the primary melanoma was as follows: trunk 35%; lower limbs, 45%; upper limbs, 18%; and head and neck, 2%. Blue dye injection for SLN identification was performed in all cases; preoperative lymphoscintigraphy was done in 440 patients, and an intra-operative probe for a radio-guided biopsy was used in 141 cases. Overall, the SLN identification rate was 88%. In 68% of the patients, only one SLN was identified, whereas two and three or more SLN were detected in 24% and 8% of the remaining cases, respectively. RESULTS: Overall SLN positivity rate was 18%. Intra-operative frozen section examination was performed in 39% of the cases and was helpful in detecting occult localizations only in 47% of the positive SLNs. Distribution of positive cases by primary thickness was as follows: < 1mm: 2%; 1-1.99 mm: 7%; 2-2.99 mm: 13%; and > or = 3 mm: 31%. Positive nonsentinel lymph nodes were found in 22% of cases with positive SLN submitted for selective dissection. No complications due to the procedure were registered. Of 710 patients who were evaluated, 40 (6%) presented a regional nodal relapse after a negative SLN biopsy and underwent a delayed therapeutic dissection. From the 710 enrolled cases, 638 (88.5%) were alive without evidence of disease at the time of this writing. A multivariate analysis showed SLN status as one of the most significant prognostic factors (P = .000) along with thickness (P = .001) and ulceration (P = .015) of primary tumor. CONCLUSIONS: These data confirm the feasibility and safety of the SLN technique for selecting patients to submit to a radical node dissection. The data represent the basis for a future trial by the WHO Melanoma Program in this field to evaluate the most appropriate surgical approach for treating patients with occult regional nodal metastases.

Adolescent↗
PubMed2000

What is the most promising strategy for the treatment of metastasizing melanoma?

The treatment of patients with metastasizing melanoma, still one of the most deadly diseases in modern medicine, ranks among the greatest challenges that a clinician has to face. Metastatic melanoma also is one of the most profound sources of clinical frustration, since it provides far more ultimately defeating experiences than clinical victories. At the same time, the fascinating biology of melanoma has invited the study of this neuroectodermal tumor as a model system for dissecting many of the key problems of modern oncology, ranging from molecular oncogenesis via the controls of tumor proliferation, apoptosis, invasion, metastasis, and angiogenesis to tumor immunosurveillance and tumor drug resistance. Together with the dire need to develop more effective treatment modalities for improving both life expectancy and quality of life of affected patients, this has made metastatic melanoma a favorite model for the exploration of innovative strategies for tumor management. Encouragingly, many of these have already generated very promising results in animal models. However, this impressive level of research progress in conquering melanoma in the animal room contrasts rather pitifully with the actual progress made on the ward. This CONTROVERSIES feature, therefore, critically and soberly reviews the state of the art of treating metastatic melanoma today (distinguishing between nodal and distant metastases), and sharply defines unresolved or comparatively neglected key problems. In addition, this feature highlights several novel, provocative, hitherto underappreciated, yet potentially promising treatment approaches that deserve systematic exploration. Hopefully, this will offer further inspiration for the design and pursuit of innovative anti-melanoma strategies off-the-beaten-track.

Humans↗
PubMed2000

First-line chemotherapy with vinorelbine and paclitaxel as simultaneous infusion in advanced breast cancer.

Based on preclinical data showing a synergistic activity of simultaneous administration of vinorelbine and paclitaxel, we carried out a phase II trial in previously untreated advanced breast cancer patients. Treatment consisted of vinorelbine 25 mg/m(2) and paclitaxel 150 mg/m(2), both drugs given by intravenous infusion over 3 h on day 1, with cycles repeated every 3 weeks. Granulocyte colony-stimulating factor, 300 microg subcutaneously, was given on days 7-12 to the first 10 patients. From October 1995 to January 1997, 43 patients with advanced breast cancer entered the study, and 41 were evaluable for response. We obtained 2 complete responses (5%) and 18 partial responses (44%), for an overall response rate of 49% (95% CI 34-64%). Median time to response, time to progression and survival were 2, 7 and 22 months, respectively. Myelosuppression was the dose-limiting toxicity, with G4 neutropenia in 21% and neutropenic fever in 7% of the patients. Other toxicities were mild. Simultaneous infusion of vinorelbine and paclitaxel is a well-tolerated and active regimen in metastatic breast cancer, with overall results similar to those reported with more toxic regimens; furthermore, it may be a good option in patients with anthracycline contraindications.

Adult↗