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Biomedical subjects

A Tucci

Publications and source records attributed to A Tucci.

At least 19 recordsLinked to original sources
PubMed2007

Monitoring of the heavy-metal hyperaccumulation in vegetal tissues by X-ray radiography and by femto-second laser induced breakdown spectroscopy.

This article reports on the utilization of X-ray microradiography and laser induced breakdown spectroscopy (LIBS) techniques for investigation of the metal accumulation in different part of leaf samples. The potential of the LIBS-analysis for finding the proper plant species for phytoremediation is compared with the results of microradiography measurements at the HERCULES source at ENEA, Rome (Italy) and X-ray microradiography experiments at the ELETTRA Synchrotron, Trieste (Italy).

Cadmium↗
PubMed2005

Real-time detection of Helicobacter Pylori infection and atrophic gastritis: comparison between conventional methods and a novel device for gastric juice analysis during endoscopy.

BACKGROUND AND STUDY AIMS: Gastric juice may represent a valuable source of clinicopathological information if properly analyzed. We evaluated the reliability and clinical validity of data obtained using an innovative device (the "Mt 21-42") that analyzes gastric juice, thus allowing the identification of Helicobacter pylori infection and atrophic gastritis of the oxyntic mucosa during endoscopy. METHODS: Validation studies were carried out to evaluate the measuring performance of the device. In addition, the H. pylori status and the presence of atrophic gastritis were assessed in 150 patients undergoing upper gastrointestinal endoscopy. In all these patients the Mt 21-42 device was used to assist endoscopy. Conventional tests (involving histology, urease testing, urea breath testing, anti- H. pylori IgG, serum gastrin, pepsinogen, intrinsic factor and parietal cells autoantibodies, vitamin B12, and folate) were also performed for comparison with the Mt 21-42 results. RESULTS: The measuring performance of the Mt 21-42 was good; for pH, the relative percent error and the coefficient of variation were 1.9 % +/- 4.2 and 1.3 %, respectively, and for ammonium they were 0.1 % +/- 0.2 % and 2.1 %. For the detection of H. pylori infection, the sensitivity and specificity of the device (96.7 % and 94.3 %) were similar to those of the urea breath test (90.5 % and 93.3 %) and serology (87.1 % and 88.8 %), and higher than those of the urease test (78.6 % and 98.7 %; P < 0.01) and routine histology (94.3 % and 76.3 %; P < 0.05). When compared with the currently available standard methods, use of the Mt 21-42 was found to be the most sensitive technique for the detection of atrophy (94.7 % vs. 5.3 % - 47.4 %; P < 0.001); the device failed to detect the disease in only one case (5 %), whereas failure rates of 53 % - 95 % were reported with the conventional methods. CONCLUSION: Atrophic gastritis of the oxyntic mucosa is a risky condition that often goes undetected in current clinical practice. The Mt 21-42 is an effective, useful, and desirable tool that may help to overcome this diagnostic limitation; it produces time and cost savings and also allows the detection of H. pylori infection.

Adolescent↗
PubMed2005

Oral cavity lymphomas in immunocompetent and human immunodeficiency virus infected patients.

Oral cavity lymphoma (OCL) seems to occur more frequently in HIV-positive patients, but it is presently unknown whether HIV-related immune deficit plays a role in modifying the prevalence and the characteristics of these lymphomas. To clarify this issue, we compared OCL occurring in immunocompetent and HIV-positive patients. A comparison was made between cases of OCL occurring among 543 and 123 NHL consecutively diagnosed at a single center in immunocompetent and HIV-positive patients respectively. The prevalence of oral cavity involvement at diagnosis was significantly lower in the immunocompetent subgroup (HIV-negative: 1.66%; HIV-positive: 7.3%, P = 0.002). Extranodal T/NK nasal-nasal-type lymphoma (ET/NK-NL) was observed in 3 of 9 immunocompetent patients, whereas plasmablastic lymphoma (PBL) was observed in 3 of 9 HIV-positive patients. EBV expression correlated with HIV-positivity. Response to treatment was similar between the two subgroups, but the overall prognosis was significantly worse among HIV-positive patients. Median survival was 34 months in immunocompetent vs. 9 months in HIV-positive patients (P < 0.01). A higher frequency of oral cavity lymphoma was associated with HIV infection. ET/NK-NL and PBL seemed to be clinical entities characteristically related to immunocompetent and HIV-positive subgroups, respectively. Chemotherapy was feasible and effective in both subgroups, although a poor prognosis was associated with immunodeficiency.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Interactions between saporin, a ribosome-inactivating protein, and DNA: a study by atomic force microscopy.

Saporins are enzymes belonging to the PNAG class (polynucleotide: adenosine glycosidase), plant enzymes commonly known as ribosome-inactivating proteins (RIP), as a result of their property of irreversibly damaging eukaryotic ribosomes. Direct imaging with tapping-mode atomic force microscopy (AFM) has been used to study pGEM-4Z plasmid DNA binding to the saporin-SO6 (isoform from Saponaria officinalis seeds). Saporin wrapped the plasmidic DNA, and distribution of the enzyme molecules along the DNA chain was markedly variable; plasmid digested with saporin-SO6 appeared fragmented or topologically modified. The supercoiled DNA strands were cleaved, giving rise to a linearized form and to relaxed forms. Electrophoretic analysis of the effect of standard preparations of saporin-SO6 on pGEM-4S confirmed the presence of DNA strand-cleaving activity.

DNA↗
PubMed2005

[Growth curves in pediatrics. Pilot study in a city of south of Italy].

AIM: In the past years the body composition assessment in pediatric subjects showed great changes due to the different quality of life and different diet habits. Over-weight and obesity increased tremendously not only in the industrialized societies but also in developing countries. Growth curves developed in the 60s need to be revises in the light of these changes and population specific curves are needed to follow a population with different life style and energy intake. The aim of this study was to evaluate, in a city of South Italy (San Severo), pediatric subjects in order to create growth curves. METHODS: Between May 1999 and October 2000 we evaluated 2,262 subjects: 1,172 (51.8%) males and 1,090 (48.2%) females, age range 6-11 years (mean 8.48 +/- 2.28 years). Height, weight, thoracic circumference and body mass index (BMI) were measured by the same expert operator. RESULTS: Tables and figures for weight, height, thoracic circumferences and BMI at 3 degrees, 50 degrees, 97 degrees centile for age and gender were presented. A comparison between 50 degrees centile for BMI in males and females were also done showing the different development related to gender. CONCLUSIONS: The results obtained underline the importance of an auxologic follow-up of the pediatric subjects in order to evaluate their correct development. The specific growth curves available make it possible to analyze the development of subjects in comparison with the subjects studied for the curves development. Moreover, the importance of the BMI curve and the relationship of the 50 degrees centile in males and females showing the different growth curve related to gender, is underlined.

Age Factors↗
PubMed2002

Volumetric determination of the wear of ceramics for hip joints.

Osteolysis relating to the reaction cascade to wear debris is the main cause of the failure of arthroprostheses. New materials are still under development to minimise the wear of joints and to improve in this way the performance of total joint replacements. Testing the wear performance of very low wear materials is a rather sophisticated technique. Currently, the worn volume is calculated from the weight variations of the sample, observed from wear testing. This method may be limited especially when very low weight differences are to be evaluated on high hardness, high-density materials like CoCr alloys or ceramics like alumina or zirconia. In the present work, the tribological behaviour of ceramic biomaterials like alumina, Y-TZP and alumina-zirconia composites was evaluated by a pin-on-disc apparatus under different testing conditions. The worn volume was calculated by the use of 3-D (three-dimensional) optical profilometry data. Comparison between 3-D optical profilometry and gravimetric wear data shows the better accuracy of the profilometric method in the determination of wear rate in the range of 10(-7) mm3 (mN(-1)) or lower.

Biomechanical Phenomena↗
PubMed2002

Phase I study of twelve-day prolonged infusion of high-dose ifosfamide and doxorubicin as first-line chemotherapy in adult patients with advanced soft tissue sarcomas.

PURPOSE: To determine whether a prolonged 12-day continuous infusion allows the administration of high-dose ifosfamide (IFO) with an acceptable toxicity profile when combined with full-dose doxorubicin (Adriamycin; ADM) as first-line chemotherapy in patients with advanced soft tissue sarcomas. PATIENTS AND METHODS: Escalating doses of continuous infusion IFO (8-15 g/m2) given on days 1 to 12 in combination with ADM 75 mg/m2 given on day 8 and prophylactic granulocyte colony-stimulating factor support were administered every 4 weeks to 35 chemonaïve patients with advanced soft tissue sarcomas. RESULTS: The maximum tolerated dose was IFO 15 g/m2. Hematological toxicity was the main dose-limiting toxicity and was dose dependent. Furthermore, thrombocytopenia was cumulative. Grade 4 (WHO) neutropenia and thrombocytopenia were recorded in 48% and 14% of courses, respectively. Eight patients experienced febrile neutropenia. A partial response was observed in 16 out of 30 assessable patients [53%, 95% confidence interval (CI) 25-63]; median time to progression was 25 weeks (range 4-91). CONCLUSIONS: This study proved that a prolonged 12-day continuous infusion allows an increase in the total IFO dose that can be safely combined with ADM. A multicentric phase II study by the Italian Sarcoma Group to assess its antitumor activity is currently ongoing in patients with advanced soft tissue sarcomas.

Adult↗
PubMed2001

Isolation and morphological characterisation of UHMWPE wear debris generated in vitro.

Wear tests are generally carried out on materials used in prosthetic hip implants, in order to obtain a better understanding of the tribological processes involved and improve the quality control of joint prostheses, directed towards reducing the risk of implant failure of innovative prostheses. Ceramic femoral heads of mixed alumina-zirconia oxides as well as zirconia and alumina single oxide heads were tested against UHMWPE acetabular cups in a hip joint simulator. Polyethylene cups and ceramic femoral heads were mounted in a simulator apparatus moving according to a sinusoidal function, under load and in the presence of bovine calf serum as lubricant. Wear particles were isolated from the bovine calf serum collected during the wear tests. An easy to follow method was used to separate the wear particles from the lubricant. Chemical digestive methods were used to separate the wear particles from the lubricant and the isolated particles were studied using scanning electron microscopy. The morphologies of the polyethylene debris showed considerable differences, both in size and shape of the particles, as a function of the coupled head material.

Animals↗
PubMed2001

Helicobacter pylori infection and gastric function in patients with fundic atrophic gastritis.

In the present study we evaluated the relation among histology, H. pylori, IgG to H. pylori, gastric emptying, and acid secretion in 43 patients with fundic atrophic gastritis. On the basis of gastric acid secretion, patients were divided into three subgroups: patients with preserved acid secretion (Group 1), patients with hypochlorhydria (Group 2), and patients with achlorhydria (Group 3). Fundic glandular atrophy was more severe in hypoachlorhydric patients than in those with preserved acid secretion (P < 0.05 vs Group 2, P < 0.005 vs Group 3). H. pylori colonization was found in 94% of patients in Group 1, in 61% of patients in Group 2, and in only 8% of patients in Group 3 (P < 0.001 vs Group 1, P < 0.05 vs Group 2). Conversely, serological positivity to H. pylori was high in all three subgroups of patients (100% in Group 1, 77% in Group 2, 92% in Group 3). Gastric emptying was delayed in atrophic patients, particularly in those with hypoachlorhydria. Our data suggest that fundic atrophic gastritis represents a possible end stage of H. pylori infection, characterized by a progressive disappearance of the bacterium and a progressive deterioration of gastric functions.

Achlorhydria↗
PubMed2001

Phase I study of a weekly schedule of oxaliplatin, high-dose leucovorin, and infusional fluorouracil in pretreated patients with advanced colorectal cancer.

PURPOSE: To identify the maximum tolerated dose (MTD) and dose limiting toxicities (DLT) of oxaliplatin (L-OHP) given on a weekly schedule including fixed doses of leucovorin (LV) and infusional 5-fluorouracil (5-FU), to define the toxicity profile of this regimen and to find preliminary evidence of its activity in pretreated patients with metastatic colorectal cancer (MCRC). PATIENTS AND METHODS: Twenty-one patients with progressive disease, treated with fluoropyrimidines and with histologically measurable MCRC entered into this phase I study. Fixed doses of LV (500 mg/m2) followed by a 48-hour 5-FU 2600 mg/m2 infusion (5-FU48h) were administered with escalating doses of L-OHP, starting from 60 mg/m2 and with stepwise increments of 5 mg/m2. No intra-patient dose escalation was allowed. Treatment was given once a week for four consecutive weeks, followed by a one-week rest period. RESULTS: Three dose levels were tested. The MTD was L-OHP 70 mg/m2 since two of the three patients showed dose-limiting diarrhea and the third developed neutropenia during the first cycle of chemotherapy. Most patients complained of mild peripheral sensitive neurotoxicity, which was related to the cumulative dose of L-OHP. Treatment delays were necessary for a total of 42 cases, but only in II of 42 after the pre-arranged 10% dose reduction of 5-FU (2300 mg/m2). Sixteen patients were evaluable for response: seven (33%; 95% confidence interval (CI): 14.6%-57.0%) were considered to show a major response (one complete), six showed a stable disease, and in addition progressive disease was observed in three patients. CONCLUSIONS: Our results show that L-OHP, LV and 5-FU can be administered safely and repetitively using a weekly schedule. Diarrhea and neutropenia are the DLT of this regimen. Its activity and its manageable toxicity profile deserve further evaluation in chemotherapy-naïve MCRC patients. The doses recommended for phase II trials are: L-OHP 65 mg/m2, LV 500 mg/m2 and 5-FU48h 2300 mg/m2 infusion given on a weekly-times-four schedule followed by a one-week rest period.

Aged↗
PubMed2000

Instrumental validation of percutaneous transmyocardial revascularization: follow-up data at one year.

BACKGROUND: Despite the clinical efficacy of percutaneous transmyocardial revascularization (PTMR), up to date there are still no instrumental validations to demonstrate both the improved perfusion of treated areas and cardiac function. METHODS: During the first year of follow-up after PTMR, 27 patients (group A) underwent 99mTc MIBI exercise-single photon emission tomography (SPET), while 30 patients (group B) underwent serial transthoracic echocardiography (TTE) evaluations with analysis of cardiac volumes and subendocardial layer thickness in systole. RESULTS: All 57 patients had a significant angina Canadian Cardiovascular Society (CCS) class improvement. Group A patients (75%) had improved exercise-SPET perfusion in treated areas at 12 weeks after PTMR, and at the next follow-up. Group B patients had non-significant reduction in global volume and no significant change in ejection fraction. However, there was an improvement in thickness of the subendocardial-treated areas in systole that persisted during follow-up. CONCLUSIONS: The use of SPET and TTE validates the clinical efficacy of PTMR.

Aged↗
PubMed2000

Gastric emptying and dyspeptic symptoms in patients with nonautoimmune fundic atrophic gastritis.

Our aim was to evaluate the relationship between gastric emptying and demographic, clinical, histological, and secretory features in patients with nonautoimmune fundic atrophic gastritis. Only 31% of 45 patients with fundic atrophic gastritis presented with achlorhydria. Scintigraphic gastric emptying of solids was delayed compared to healthy controls. Patients with achlorhydria showed gastric emptying rates lower than those with preserved acid secretion. Significant, but weak, correlations were observed between emptying rates and both peak acid output (Rs = 0.33) and serum gastrin levels (Rs = -0.36), but not with grading of mucosal atrophy. No symptom differences were observed between patients with or without achlorhydria, but a weak correlation was detected between peak acid output and the severity of epigastric pain (Rs = 0.40). In conclusion, patients with fundic atrophic gastritis present delayed gastric emptying that is weakly related to the reduction of the acid secretion and the raising of serum gastrin levels rather than to the severity of the atrophy.

Achlorhydria↗
PubMed1999

PCR-based restriction pattern typing of the vacA gene provides evidence for a homogeneous group among Helicobacter pylori strains associated with peptic ulcer disease.

The results of PCR-based molecular typing of Helicobacter pylori strains by restriction fragment length polymorphism analysis of a 1, 161-bp nucleotide sequence of the midregion of the vacA gene are reported. A total of 48 H. pylori strains isolated from gastric biopsy specimens obtained from 18 patients with peptic ulcer dyspepsia, 15 patients with nonulcer dyspepsia, and 15 asymptomatic H. pylori-infected subjects were studied. Highly heterogeneous restriction patterns were obtained by digestion of PCR products with SauII, BglII, and HhaI, whereas HaeIII digestion resulted in a strictly homogeneous profile for H. pylori strains isolated from 14 of 18 (77.7%) patients with peptic ulcer dyspepsia, but a strictly homogeneous profile was found for strains from only 8 of 15 (53.3%) patients with nonulcer dyspepsia (P = 0.163) and 5 of 15 (33.3%) asymptomatic H. pylori-infected subjects (P = 0.014). A potentially important aspect of the results obtained is the clinical relevance, since a single restriction pattern seems to be able to identify the majority of H. pylori strains associated with peptic ulcer disease.

Adult↗
PubMed1998

Reversal of fundic atrophy after eradication of Helicobacter pylori.

OBJECTIVES: We sought to evaluate the effect of Helicobacter pylori eradication in patients with fundic atrophic gastritis. METHODS: Acid secretion, gastric emptying, and histology were evaluated in 20 patients with fundic atrophic gastritis and H. pylori infection. After investigation, 10 patients (Group 1) received an eradicating treatment and 10 (Group 2) did not receive any treatment. One year later, the baseline investigations were repeated. Subsequently, patients in Group 2 received the same treatment given to patients in Group 1 and were reevaluated 12 months later. A further follow-up was performed in both groups 36 months after the treatment. RESULTS: At 1-yr follow-up, all the patients in Group 1 were H. pylori negative whereas all the patients in Group 2 were still infected. In Group 1, there was a significant improvement of both fundic atrophy and acid secretion, compared with baseline (p < 0.01). In Group 2, no substantial modification of either histological or functional parameters was observed at the first follow-up; conversely, a significant (p < 0.01) improvement of fundic atrophy and acid secretion was detected in these patients 12 months after eradication of the bacterium. Histological pattern remained unchanged at 36 months of follow-up in both groups. Gastric emptying remained, on the average, unaffected by the treatment; however, three patients with delayed gastric emptying at entry had normal gastric emptying after eradication of H. pylori. CONCLUSIONS: Our data suggest that mucosal atrophy can be reduced or even reversed by the eradication of H. pylori, and this is associated with a recovery of gastric function.

Amoxicillin↗