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R Amato

Publications and source records attributed to R Amato.

At least 19 recordsLinked to original sources
PubMed2006

A multi-step approach to time series analysis and gene expression clustering.

MOTIVATION: The huge growth in gene expression data calls for the implementation of automatic tools for data processing and interpretation. RESULTS: We present a new and comprehensive machine learning data mining framework consisting in a non-linear PCA neural network for feature extraction, and probabilistic principal surfaces combined with an agglomerative approach based on Negentropy aimed at clustering gene microarray data. The method, which provides a user-friendly visualization interface, can work on noisy data with missing points and represents an automatic procedure to get, with no a priori assumptions, the number of clusters present in the data. Cell-cycle dataset and a detailed analysis confirm the biological nature of the most significant clusters. AVAILABILITY: The software described here is a subpackage part of the ASTRONEURAL package and is available upon request from the corresponding author. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Artificial Intelligence↗
PubMed2004

[Epidemiology of salmonellosis in Caltagirone area (Sicily)].

The authors report the results of an epidemiological-clinical study concerning episodes of salmonellosis observed in Caltagirone (CT) from 1999 to 2002 and reported to the National Centre for Control of pathogen enterobacteria (enter-net Italy). Overall, two hundred and forty strains of salmonella were isolated, typed and in vitro tested for susceptibility to eleven different antibiotics. Cases were evaluated according to patients' age, risk factors and clinical findings. Salmonella enteritidis (39%) was the most prevalent serovar followed by S. typhimurium (16%), S. newport (6%), S. salamae (5%) and others. The highest rate of antibiotic resistance was observed in S. typhimurium.

Adolescent↗
PubMed2001

Response of biochemical markers of bone turnover to estrogen treatment in post-menopausal women: evidence against an early anabolic effect on bone formation.

Bone loss following menopause can be prevented or reduced by estrogen replacement therapy (ERT). The primary action of estrogen on bone is generally considered to be antiresorptive, but some evidence would also suggest a stimulatory effect on bone formation. The aim of this study was to assess the effect of ERT on biochemical markers of bone resorption (urinary pyridinoline and deoxypyridinoline), and of bone formation (bone-specific alkaline phosphatase--B-ALP, and the C-terminal propeptide of type I collagen--CICP) in a group of 25 postmenopausal women with no evidence of osteoporosis. Since the suggested anabolic effect of estrogen seems to take place in the early period of ERT, we measured the response of markers immediately before and after the start of treatment (30, 60, 120 and 180 days). The markers of bone resorption started to decrease at 30 days and remained low thereafter. We also observed a similar decrease in serum levels of B-ALP and CICP, reflecting a reduction of bone formation rate. Our data would indicate that ERT at the given dose does not have early anabolic effects on bone, in addition to its recognized suppressive effect on bone resorption.

Alkaline Phosphatase↗
PubMed2001

An observational study on the epidemiology of respiratory tract bacterial pathogens and their susceptibility to four injectable beta-lactam antibiotics: piperacillin, piperacillin/tazobactam, ceftazidime and ceftriaxone.

Bacterial infections of the respiratory tract account for a large proportion of total medical consultations in general practice. In recent years, antibiotic resistance has increased alarmingly in a number of bacterial species that are common causes of these infections. The aim of this observational study was to determine the antibiotic resistance of microbial agents isolated from patients with acute or acutely exacerbated respiratory infections. Subjects recruited as potential sources of bacteria were either outpatients seen in a number of specialized clinics and hospital practices, or hospitalized patients. Overall, 648 consecutive patients (67% male, mean age 48.1+/-27.0 years) with infection of the upper or lower respiratory tract were observed during a 13-month period. A total of 551 pathogenic microbial strains were isolated and tested for their in vitro susceptibility to piperacillin, piperacillin/tazobactam, ceftazidime, and ceftriaxone. Among all isolates, the four most frequent pathogens were Pseudomonas aeruginosa (132 isolates, 24%), Streptococcus pyogenes (99 isolates, 18%), Staphylococcus aureus (93 isolates, 17%), and Klebsiella pneumoniae (46 isolates, 8%). The susceptibility of gram-positive isolates ranged from 97.5% to 95.1%, and no remarkable difference was found in the antibacterial activity of tested b-lactam antibiotics. The susceptibility of gram-negative isolates to piperacillin and piperacillin/tazobactam was also similar: 96.5% and 97.1%, respectively. In contrast, differences were found between piperacillin (or piperacillin/tazobactam) and either ceftazidime (p=0.003) or ceftriaxone (p<0.0003) in gram-negative isolates. We conclude that, despite the extensive use of beta-lactam antibiotics (piperacillin, ceftazidime, and ceftriaxone) in medical practice during the past three decades, the susceptibility of the most common pathogens involved in the etiology of upper and lower respiratory tract infections to these antibiotics is still high. In particular, bacterial resistance developed by gram-positive organisms against piperacillin is negligible and not alarming.

Adolescent↗
PubMed2001

Serum lactate dehydrogenase isoenzyme 1 and prediction of death in patients with metastatic testicular germ cell tumors.

The International Germ Cell Cancer Collaborative Group study of patients with metastatic testicular germ cell tumors showed that catalytic concentration of serum lactate dehydrogenase (S-LD), serum alpha-fetoprotein concentration (S-AFP), and serum human chorionic gonadotropin concentration (S-hCG) predicted death from tumor. The recent international TNM classification (T primary tumor, N lymph node metastasis, M distant metastasis) is based on these results. The aim of our study was to evaluate whether catalytic concentration of S-LD isoenzyme 1 (S-LD-1) was a better predictor than the criteria used for the international classification. In an evaluation series of 44 patients from Odense University Hospital, Denmark, a raised S-LD-1 (>1.0 x upper limit of reference values) had a predictive value for death from tumor in 5-years observation of 46%. The predictive value was 46% for S-LD, 25% for S-AFP, and 40% for S-hCG. A normal SLD-1 had a predictive value for survival over 5-years observation of 100%. It was 81% for S-LD, 75% for SAFP, and 77% for S-hCG. The fraction of the patients who died of tumor and had a raised tumor marker value was 100% for S-LD-1, 46% for S-LD, 9% for S-AFP, and 18% for S-hCG. The fraction of patients with a normal serum tumor marker value among those who survived was 61% for S-LD-1, 81% for S-LD, 94% for SAFP, and 94% for S-hCG. A validation series of 37 patients treated at the University of Texas MD Anderson Cancer Center showed similar findings. Combining the patients in the two series, a raised value of SLD-1 classified more patients into a subgroup with an impaired survival (53%) than S-LD (35%), S-AFP (6%), or S-hCG (11%), and the high risk subgroups based on the international classification (40%). The findings have implications for the staging and treatment of patients with metastatic testicular germ cell tumors.

Biomarkers, Tumor↗
PubMed2000

A Phase II trial of bryostatin-1 for patients with metastatic renal cell carcinoma.

BACKGROUND: Patients with metastatic renal cell carcinoma have a poor prognosis and no standard therapy is available. The authors performed a Phase II trial of the novel agent bryostatin-1 in this patient population. METHODS: In all, 30 patients with measurable, previously untreated metastatic renal cell carcinoma were studied. Patients had excellent physiologic reserve and preserved performance status. Bryostatin-1 (25 microg/m(2)) was given in the PET (polyethyleneglycol, ethanol, and Tween 80) formulation as a 30-minute intravenous infusion on Days 1, 8, and 15 of each 28-day cycle. In general, treatment was continued until disease progression. RESULTS: Two patients had significant objective responses, although methodologic problems made interpretation difficult. The median time to progression for all patients was 2.1 months; the median overall survival was 13.1 months. The treatment was generally well tolerated. Myalgia was the most common adverse event. One patient died while on study. This was a sudden death for a patient receiving a 15th cycle of therapy. Aside from this patient (for whom the correlation of study drug to death was not clear), no Grade 4 nonhematologic toxicity was encountered in more than 150 treatment courses delivered. CONCLUSIONS: There is minimal, if any, clinically relevant single-agent activity of bryostatin-1 at this dose and schedule for patients with metastatic renal cell carcinoma.

Adult↗
PubMed2000

Radioimmunodetection of residual, recurrent or metastatic germ cell tumors using technetium-99 anti-(alpha-fetoprotein) Fab' fragment.

PURPOSE: The majority of patients with germ cell tumors are cured by multimodality therapy that consists of cisplatin-based chemotherapy and/or surgical resection. Serum tumor markers and conventional radiographs are utilized to stratify patients into treatment categories. Efforts to individualize chemotherapy or minimize surgical interventions without compromising outcome are important. Immunomedics (Morris Plains, New Jersey) developed an anti-(alpha-fetoprotein) (anti-AFP) monoclonal antibody IMMU-30 labeled with 15-20 mCi technetium-99, and the purpose of this study is to determine the sensitivity and specificity of radioimmunoscintigraphy using 99mTc anti-AFP antibody for the diagnosis of active germ cell tumors. METHODS: A group of patients with germ cell tumors were enrolled in a non-prospective fashion and 48 AFP scans using 99Tc anti-AFP Fab' fragment were obtained. At the time of the AFP scan, serum AFP was elevated in 40 measurements with a median level of 21 ng/ml (1.6-66, 210.0 ng/ml). AFP scans were obtained at the initial staging, during treatment, at relapse or at long-term follow-up and compared with conventional radiographs done within 4 weeks of the AFP scans. RESULTS: An overall diagnostic sensitivity of 89% and specificity of 58% were obtained. CONCLUSIONS: AFP scanning appears useful and to be sufficiently sensitive to justify prospective studies comparing the procedure with conventional imaging.

Adolescent↗
PubMed2000

Flavopiridol, a novel cyclin-dependent kinase inhibitor, in metastatic renal cancer: a University of Chicago Phase II Consortium study.

PURPOSE: Flavopiridol is the first cyclin-dependent kinase (cdk) inhibitor to enter clinical trials. Serum levels of flavopiridol obtained during phase I studies were sufficient to inhibit in vitro cancer cell growth. Because responses were observed in kidney cancer patients in the phase I trials, we performed a phase II trial of flavopiridol in this patient population. PATIENTS AND METHODS: Thirty-five minimally pretreated patients were accrued using a standard two-step mechanism. Flavopiridol (50 mg/m(2)/d) was administered by continuous infusion for 72 hours every 2 weeks, and response was evaluated every 8 weeks. Peripheral blood mononuclear cells (PBMCs) were collected at baseline, at completion of drug infusion, and on day 7 of the first therapy cycle, and cell cycle parameters after phytohemagglutinin and interleukin-2 stimulation were assessed. RESULTS: There were two objective responses (response rate = 6%, 95% confidence interval, 1% to 20%). The most common toxicities were asthenia, occurring in 83% of patients (grade 3 or 4 in 9%), and diarrhea, occurring in 77% of patients (grade 3 or 4 in 20%). Also, nine patients (26%) experienced grade 3 or 4 vascular thrombotic events, including one myocardial infarction, two transient neurologic ischemic attacks, four deep venous thrombosis, and two pulmonary emboli. Cell cycle studies did not reveal any effect of flavopiridol on stimulated PBMCs. CONCLUSION: Flavopiridol, at the dose and schedule administered in this trial, is ineffective in metastatic renal cancer. In addition to the diarrhea observed in phase I studies, we also observed a higher incidence of asthenia and serious vascular thrombotic events than expected.

Adult↗
PubMed2000

Thalidomide for recurrent renal-cell cancer in a 40-year-old man.

A pilot study was performed at The University of Texas M. D. Anderson Cancer Center to determine the feasibility of using thalidomide in a population of renal-cell carcinoma patients who had progressive disease despite chemotherapy and immunotherapy. Metastatic renal-cell carcinoma patients with adequate oral function were entered onto a study after signing an internal review board-approved informed consent. There were no exclusion criteria for prior therapy. Nineteen previously treated patients and one untreated patient with progressive renal-cell carcinoma received oral thalidomide as a single agent. The starting dose was 200 mg and the dose was increased by 100 to 200 mg every week until it reached 1,200 mg/d. Response was assessed on the basis of a radiographic reduction of the metastatic sites involved. A case report describing one of the patients involved in the pilot trial is included.

Adenocarcinoma, Clear Cell↗
PubMed1997

Migraine with and without aura in the same patient: expression of a single clinical entity?

Migraine with aura and migraine without aura may be different clinical expressions of one disease. This theory is debated, however. In order to further address the issue, we administered a standardized questionnaire to 45 migraineurs. The results indicate a significant overlap between migraine with and without aura, most importantly with respect to response to therapy; 70% of patients had similar responses.

Adult↗
PubMed1996

Optimal delivery of perioperative chemotherapy: preliminary results of a randomized, prospective, comparative trial of preoperative and postoperative chemotherapy for invasive bladder carcinoma.

PURPOSE: We performed a planned interim analysis of a randomized trial comparing initial to postoperative chemotherapy for bladder cancer. The purpose of our analysis was to detect early evidence of survival differences, tolerance to therapy influenced by the sequence of treatment, predictive value of clinical state and influence of methotrexate, vinblastine, doxorubucin and cisplatin (M-VAC) on bladder resectability. MATERIALS AND METHODS: A total of 100 consecutive patients were randomized to receive 2 M-VAC courses before and 3 courses after surgery (group 1) or 5 adjuvant M-VAC courses following cystectomy (group 2). Survival, clinical response, clinical and pathological stage, and toxicity were evaluated in this second timed interim analysis. RESULTS: Of all patients 70% received at least 4 M-VAC courses. Overall survival at 31.7 months (range 1.8 to 87.7) was similar in groups 1 (60%) and 2 (63%), and independent of clinical stage. Preoperative clinical staging accurately identified patients at high risk for recurrence, while 37 of the 48 group 2 patients (77%) were considered at high risk by pathological staging (P3b, P4a, node-positive and unresectable disease). Comparison of pathological stage revealed that 14 of the 51 group 1 patients (28%) achieved stage P0 while only 1 of the 48 group 2 patients (2%) had P0 disease at surgery (p= 0.00043). Disease was unresectable in 3 group 1 (6%) and 8 group 2 patients (17%, p= 0.09). Tolerance to treatment was not significantly different in the 2 study arms. CONCLUSIONS: No survival advantage was noted between neoadjuvant and adjuvant M-VAC in our interim analysis. However, results suggest that M-VAC chemotherapy may be effective in increasing the resectability of localized bladder cancer and may contribute to organ preservation. Clinical stage was a reliable predictor of pathological findings at surgery. Future studies can use clinical staging to determine therapy before surgery for the select stages that we treated. Identification of the subset likely to achieve complete pathological remission will permit the selection of patients for organ preservation strategies.

Adult↗
PubMed1995

A phase I trial of intermittent high-dose alpha-interferon and dexamethasone in metastatic renal cell carcinoma.

BACKGROUND: Evidence exists that the toxic of alpha-interferon can be ameliorated by co-administration of dexamethasone without compromise of therapeutic efficacy. We therefore conducted a phase I trial to determine the maximum tolerated dose of intermittent interferon when combined with oral dexamethasone. PATIENTS AND METHODS: Thirty patients with metastatic renal cell carcinoma were enrolled. The starting dose of interferon was 20 million IU/m2/day given as a subcutaneous injection days 1 to 4 of each 14 day cycle. Dose levels were escalated at increments of 5 million IU/m2. Dexamethasone 4 mg was administered orally every 6 hours during administration of high-dose interferon. Low-dose maintenance interferon, 3 million IU/m2/day, was administered without dose escalation on days 5 to 14 of each cycle. RESULTS: The maximum tolerated dose of intermittent high-dose interferon was 40 million IU/m2/day. The dose limiting toxicity was fatigue. EEG abnormalities developed in five patients and neuropsychiatric parameters deteriorated significantly in seventeen. CONCLUSIONS: We conclude that co-administration of dexamethasone improves the tolerance of intermittent high-dose interferon. The results of this trial may be useful in designing high-dose interferon regimens for renal cell carcinoma and other interferon-sensitive diseases.

Administration, Oral↗
PubMed1995

Paclitaxel, cisplatin and methotrexate combination chemotherapy is active in the treatment of refractory urothelial malignancies.

PURPOSE: We investigated the activity of combination chemotherapy consisting of paclitaxel, cisplatin and methotrexate in patients with advanced urothelial cancers. MATERIALS AND METHODS: A total of 25 consecutive patients with metastatic refractory urothelial malignancies was treated with a combination of 200 mg./m.2 paclitaxel, 30 mg./m.2 methotrexate and 70 mg./m.2 cisplatin in a pilot study. RESULTS: There were no complete responses. Of 25 patients 10 (40%), including 3 of 7 with liver metastases, had a partial response. Hematological and nonhematological toxicity was tolerable. CONCLUSIONS: The combination chemotherapeutic regimen of paclitaxel, cisplatin and methotrexate is active in patients with advanced urothelial cancer and warrants further study.

Adult↗
PubMed1994

Phase II study of ketoconazole combined with weekly doxorubicin in patients with androgen-independent prostate cancer.

PURPOSE: A phase II clinical trial was performed to assess the antitumor activity and toxicity of ketoconazole in combination with doxorubicin (Adriamycin; Adria Laboratories, Columbus, OH) in patients with androgen-independent prostate cancer (AI PCa). PATIENTS AND METHODS: Thirty-nine consecutive patients whose disease progressed following castration were treated with oral ketoconazole (1,200 mg) daily and Adriamycin (20 mg/m2 in a 24-hour infusion) once weekly. Antitumor activity was assessed by the level of prostatic-specific antigen (PSA) decline. RESULTS: PSA levels decreased > or = 50% from baseline in 21 (55%; 95% confidence interval, 38% to 71%) of 38 assessable patients. We observed partial responses (PRs) in seven (58%) of 12 patients with measurable soft tissue disease (in the lung, lymph nodes, and liver). Two patients with history of atherosclerotic heart disease had a sudden cardiac death. Serious toxic reactions included grade III to V stomatitis and grade III to IV acral erythema in 11 patients (29%), and grade III to IV anal and urethral mucositis in five patients (13%). Grade III to IV neutropenia occurred in 11 patients (29%). Seventeen patients (45%) required hospitalization for complications. Fifteen patients (39%) developed hypokalemia, and 24 patients (63%) developed clinical adrenal insufficiency. CONCLUSION: The combination of ketoconazole and Adriamycin has a 55% PSA response rate in patients with AI PCa and is worthy of additional study. This treatment results in frequent adrenal insufficiency. Therefore, future studies should incorporate routine corticosteroid replacement. The cardiac complications caused by this combination should be studied further before it is widely used.

Administration, Oral↗
PubMed1993

Collecting duct carcinoma of the kidney.

Collecting duct carcinoma (CDC) is a recently recognised histological variety of renal carcinoma (RC) considered to arise from the epithelium of the collecting ducts. Diagnosis of this entity depends on well defined gross and microscopic criteria and is supported by a characteristic immunostaining pattern. The clinical features of these patients, the natural course of the disease and its response to treatment have not been clearly established. Between 1980 and 1990 we treated 12 patients (median age 43 years, range 16-62) with collecting duct carcinoma of the kidney. In addition to being relatively young, each patient had a strong family history of associated malignancies. Survival was short (median 22 months) and 11 patients presented with locally advanced or metastatic disease.

Adolescent↗