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Biomedical subjects

P Spinelli

Publications and source records attributed to P Spinelli.

At least 19 recordsLinked to original sources

Natural fluorescence of normal and neoplastic human colon: a comprehensive "ex vivo" study.

BACKGROUND AND OBJECTIVE: A microspectrofluorometric analysis on "ex vivo" samples from normal tissue and adenocarcinoma of the human colon has been performed to characterize the histological, biochemical, and biophysical bases of the autofluorescence. STUDY DESIGN/MATERIALS AND METHODS: Differences between normal and tumor tissues are found that concern both the intensity distribution and spectral shape of the autofluorescence emission. The different pattern of the fluorescence intensity can be related to the histological organization of the tissue, and involves mainly the arrangement of the submucosa, the most fluorescent layer. RESULTS: The most evident differences in the spectral shape found in the 480-580 nm range involve the stromal compartment, seem to be due to the presence of different fluorochromes, and are possibly related to the host response to the tumor. CONCLUSION: The nature and the extent of the autofluorescence modification between normal and tumor tissue in sections explain at least partly the evidence of the "in vivo" analysis and highlight the importance of excitation for full exploitation of the potentials of autofluorescence in diagnosis.

Adenocarcinoma

Absorption and excretion of cobalt in the hard metal industry.

Absorption and excretion of cobalt in the hard metal industry was investigated by means of ambient air and urine measurements in three factories with high levels of environmental cobalt pollution. In the presence of poor hygiene conditions and permission to smoking during work, there was no relationship between cobalt ambient air and cobalt urine concentrations. Such a finding was therefore attributed to a substantial skin contact. A simple experiment of skin exposure to freshly mixed or waste powder on volunteers identified a ten-fold increase of cobalt in urine in the post-exposure samples, thus confirming the contribution of dermal exposure as a route of entry. An improvement in the hygiene of the working conditions helped to investigate the relationship between exposure and excretion level. Cobalt uptake through the different routes of entry may be substantial, and requires a more prolonged exposure-free period so that the excretion rate can be reduced to the reference population level.

Absorption

Ex vivo optical properties of human colon tissue.

Using a spectrophotometer equipped with an internal integrating sphere, the absorption (mu a) and the reduced scattering (microseconds') coefficients of ex vivo human colon tissues were evaluated from reflectance and transmittance measurements. Mu a and microseconds' varied from 47.7 to 1.0 cm-1 and from 14.2 to 6.2 cm-1, respectively, on passing from 300 nm to 800 nm. These results can be used to estimate the optical penetration depths when photodynamic therapy or light-induced fluorescence procedures are used.

Absorption

Self-expanding tracheobronchial stents using flexible bronchoscopy. Preliminary clinical experience.

Endoscopic insertion of tracheobronchial stents is indicated to achieve patency of the airway in case of malignant or benign obstructing lesions. Until now, the placement of prostheses has required a rigid bronchoscope with specially designed insertion instruments. Self-expanding stents are currently used to treat stenoses of different hollow organs (vessels, urinary tract, gastrointestinal tract, bile duct, respiratory tract). We report the first case of a self-expanding stent implanted in the trachea and right main stem bronchus using flexible videobronchoscope under local anesthesia. The procedure was easy, safe, effective, and well tolerated. No complications occurred.

Aged

Comparative analysis of results of guaiac and immunochemical tests for faecal occult blood in colorectal cancer screening in two oncological institutions.

The performances of three faecal occult blood tests, rehydrated Hemoccult (HOR), Hemoccult sensa (HOS) and Hemeselect (HSEL) on 3 days were compared in 1,725 subjects consecutively recruited in two oncological institutions in Milan and Florence. Significant differences between the results were evident as far as HOR positivity rates (7.5% vs 4.0%, respectively) and specificity (94.3% vs 97.5%, respectively) are concerned. Overall positivity rates of HOR, HOS and HSEL were 5.9%, 5.4% and 12%, respectively; significant differences were evident between HSEL and each of the two guaiac tests. Cancer was detected in eight subjects, adenoma/s in 47. Specificity estimates were 95.8%, 90.2% and 90.5% for HOR, HOS and HSEL, respectively; significant differences were evident between HSEL and the other two tests. No significant difference between tests was evident for sensitivity or positive predictive values for cancer or adenomas. In the CSPO (Florence) population (1,223 subjects; five with cancer, 16 with adenoma/s) the performances of 1-day HSEL testing were determined on the basis of the first faecal sample only and compared with 3-day HOR, HOS and HSEL testing. The positivity rates of 1-day HSEL, 3-day HOR, HOS and HSEL testing were 7.0%, 5.0%, 5.5% and 12.9%, respectively. Only 3-day HSEL positivity rate was significantly higher than 1-day HSEL. One-day HSEL specificity (94.9%) was significantly higher than 3-day HSEL (90.0%), whereas no significant difference was seen between 1-day HSEL, HOR (96.5%), and HOS (96.1%) specificity. No significant difference between tests is evident in the CSPO population as far as positive predictive values and sensitivity for cancer and adenomas are concerned.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma

Endoscopic treatment of polyps in the resected stomach.

Between 1974 and 1992, at the Department of Diagnostic and Surgical Endoscopy of Istituto Nazionale Tumori, in Milan, 27 patients with resected stomach and suffering from epithelial polyps of the gastric stump (10 lesions) and/or anastomosis (25 lesions), were endoscopically treated using electroresection (13 cases), electrocoagulation (2 cases), combined methods (electroresection plus Nd:YAG photocoagulation) (1 case) and biopsy forceps (19 cases). Complications occurred in 4 cases and consisted of hemorrhage. Seven patients developed 15 recurrences. Endoscopic treatment of polyps in patients with resected stomach is a safe and effective treatment, considering the low rate of complication.

Adult

Endoscopic treatment of upper gastrointestinal tract malignancies.

Palliative endoscopic treatment of the upper gastro-intestinal (UGI) tract includes: dilation, Nd:YAG laser photocoagulation and intubation, used alone or in combination. These procedures are usually performed on an outpatient basis and are associated with a low rate of morbidity and mortality. From 1978 to 1992, 836 patients were treated at the Endoscopy Division of the Istituto Nazionale Tumori, Milan, for inoperable primary or recurrent malignancies of the UGI-tract. Recanalization was obtained in 96% of patients treated; functional results have been computed according to the site and to the endoscopic method. Overall median survival was 6.2 months. The complication rate was 8%. Relief of dysphagia is the goal of palliative treatment in patients with inoperable neoplasms of the UGI-tract.

Aged

Rectal metal stents for palliation of colorectal malignant stenosis.

Thirteen patients with colorectal obstructing tumors were submitted to endoscopic insertion of self-expanding metal stents to restore luminal patency. The procedure was performed entirely under endoscopic control, without using fluoroscopy, during a 1-day hospitalization. The prostheses were correctly placed in 12/13 patients (92%), with no immediate complications. The mean follow-up is 7 months. Ten out of 12 patients (83%) had a permanent restoration of the luminal patency; they experienced no pain, tenesmus or any other discomfort during the follow-up period. In the remaining 2 patients long-term complications occurred and were treated by endoscopy in 1 case, and by surgical resection in the 2nd case. Self-expanding metal stents proved to be safe and effective; the main drawbacks, at present, are the lack of effectiveness of these devices in case of a fistula and their high costs.

Adult

A new technique of endoscopic implantation of self-expanding mesh stents for inoperable tracheo-bronchial malignancies.

When malignant or benign lesions obstruct the tracheobronchial tree in patients unsuitable for surgery, patency of the lumen can be maintained using endoprostheses. This procedure is traditionally performed by rigid bronchoscopy. Recently, self-expanding metal stents have been developed and used in clinical practice. We employed these stents in 3 patients suffering from advanced tracheo-bronchial tumors; in all cases the procedure was carried out with flexible videobronchoscopes under local anaesthesia.

Adenocarcinoma

Light-induced fluorescence spectroscopy of adenomas, adenocarcinomas and non-neoplastic mucosa in human colon. I. In vitro measurements.

In an attempt to evaluate whether induced fluorescence could be exploited to discriminate neoplastic from non-neoplastic tissue, fluorescence spectroscopy was performed at 450-800 nm on 83 biopsy specimens of colonic mucosa. Measurements showed that fluorescence spectra of adenoma, adenocarcinoma and non-neoplastic mucosa manifest dissimilar patterns. Nine variables, whose photophysical and/or biological bases need further investigation, were derived from the spectra. Discriminant functions between the groups of lesions were determined by using a stepwise discriminant analysis. The diagnostic test had a sensitivity of 80.6% and 88.2%, and a specificity of 90.5% and 95.2% in discriminating neoplastic from non-neoplastic mucosa and adenoma from non-neoplastic mucosa respectively. These results suggest that fluorescence spectroscopy has the potential to improve endoscopic diagnosis of premalignant and malignant lesions of colonic mucosa.

Adenocarcinoma

Endoscopic palliation of malignancies of the upper gastrointestinal tract using Nd:YAG laser: results and survival in 308 treated patients.

Three hundred eight patients with obstructing malignant tumors of the gastrointestinal tract were submitted to endoscopic Nd:YAG laser palliation. The number of sessions as well as the number of days and total energy required for initial recanalization of the stenosis were related to tumor length. Luminal patency was obtained in 94% of patients, but improved swallowing was achieved in 74% of patients. The technical success rate did not depend on tumor site, whereas functional positive results are related to the location of the stenosis, with worst results for tumors involving the upper third of the esophagus. Life-table analysis revealed that 1-year survival was 23% when a luminal patency was achieved and 7% when treatment failed.

Adult

Diagnostic accuracy of the double-contrast enema for colonic polyps in patients with or without diverticular disease.

The accuracy of the double-contrast enema for the diagnosis of polypoid lesions in the presence or absence of diverticula was evaluated by retrospectively reviewing the medical records of 202 patients subjected to examination and endoscopy. Analysis of the data on 215 polypoid lesions showed that (a) the diagnostic accuracy of the examination is not affected significantly by the presence of diverticula; (b) the sensitivity of the examination is highly dependent on the size of the polyps (smaller or larger than 0.5 cm) but not on the form (sessile or pedunculated); and (c) the positive predictive value is higher in patients without diverticula. The double-contrast enema was confirmed to be a valid method for the diagnosis of polypoid lesions.

Barium Sulfate

Esophageal intubation for malignant fistulas.

Between April 1978 and December 1989 at the Endoscopy Division of the National Cancer Institute of Milan, 140 patients were intubated for esophageal neoplasms; 19 of these subjects underwent endoscopic intubation for malignant fistulas complicated by pneumonia and/or mediastinitis. The prostheses were tolerated well and enabled the restoration of oral nutrition. The mean survival was 4.7 months (range, 0.5-17 months). No major complications occurred. Tube dislodgement was observed in 2 cases (10.5%). Two patients died of causes that were not related to the procedure.

Aged