Effectiveness of a glutaraldehyde formulation in decontamination of dental unit water systems.

AIM: Dental-medical devices may transmit infections caused by bacteria that are usually found in water distribution systems, and which are difficult to treat and control. High bacterial contamination in the water systems of dental units is due to the presence of biofilm inside the pipes. Our study evaluated the efficacy of glutaraldehyde formulated with quarternary ammonium salts (Sanicide T4) examined in a previous study, employing a series of assays to confirm or otherwise the results obtained previously. METHODS: A purification protocol for the dental unit water system, together with a protocol for daily maintenance treatment, were tested on two dental units (in the Departments of Conservative and Prosthetic Dentistry) taking specimens from the turbine, micro-engine and air-water gun. The chemical substance, at a concentration of 20 cc per litre of water, was allowed to act when the department closed, for a total of 15 days. The Sanicide T4 was handled with protective gloves and the dental units were fitted with two safety devices to avoid accidental ingestion. RESULTS: Laboratory results enabled us to compare values for bacterial load at 36 degrees C and at 22 degrees C and for Pseudomonas aeruginosa, before and after applying the test protocol. Data obtained are satisfactory except for Pseudo-monas in the fountain in the Department of Conservative Dentistry; the value was in any case below the safety level set by the American Dental Association, confirming the results obtained in our previous study. CONCLUSIONS: The two protocols may now be considered an excellent solution to control the development of biofilm. Should the product be found to be effective for a longer period of use, each dental unit should be provided with: an anti-reflux valve to stop accidental ingestion of disinfectant; a hydraulic mechanism to pump the product to the handpieces and other water supply devices; possibility of discriminating the use of the public water system from the use of that in the disinfectant circuit; an automatic mechanism whereby the disinfectant can be flushed out with drinking water every morning.

[Decontamination of dental unit waterlines using disinfectants and filters]. / Decontaminazione del sistema idrico del riunito mediante disinfezione e filtrazione.

Bacterial contamination of the dental unit water system can become a health problem for patients, particularly if they are immunodepressed. The present study has had the purpose of evaluating the effectiveness of methods of chemical decontamination using different disinfectants (peracetic acid, hydrogen peroxide, silver salts, chloramine T, glutaraldehyde T4) and methods of physical decontamination using synthetic membranes for the filtration of water. A preliminary removal procedure of the biofilm present in the waterline has been followed in a dental unit prepared on purpose for the research; subsequently different 2-week long maintenance procedures were applied using disinfectants injected by a pump and finally the bacterial contamination of the water flowing from the waterline was evaluated. The physical decontamination was performed using 0.22 mm membrane filters, which have been installed also in another dental unit, and the filtered water was analyzed to detect bacterial contamination. The preliminary procedure of biofilm removal succeeded obtaining germ-free water. Among the disinfectants used for the maintenance of the water quality only glutaraldehyde T4 was able to reduce the bacterial contamination under the limit suggested by the ADA. The membrane filter system was not able to purify the water, but when a disinfectant (peracetic acid) was used in the last part of the waterline good results were obtained. At present no decontamination system of dental waterline is available, and glutaraldehyde T4 seems to be the best disinfectant only if integrated with periodic biofilm removal for the maintenance of the water quality.

A practical technique for conformal simulation in radiation therapy of pelvic tumors.

PURPOSE: A radiological procedure, based on straightforward conventional methods, was used for a demonstration of pelvic anatomy during simulation to precisely delineate the target volume and increase the probabilities of pelvic tumor control. METHODS AND MATERIALS: Between 1990 and 1993, 450 patients with primary pelvic malignancies underwent external radiotherapy by means of photons, 6-10 MeV, with multiple-field techniques. The simulation was carried out immediately following a pelvic organs opacification (POO) by standard methods. This procedure used a minimal quantity of contrast media (barium sulphate, iodine contrast) and metallic markers to locate directly and simultaneously: (a) small intestine, (b) bladder, (c) rectum, (d) anal canal, (e) bulbous male urethra, and (f) vagina. When all these structures were clearly visualized, the procedure was scored as successfully performed. RESULTS: The sensitivity of procedure was defined as the percentage of successful pelvic organs opacification (POO) carried out in the patients. It was 98% in both women and men. Indirectly, the procedure helped us to locate the prostate, the perineum, and the uterus cervix in the same percentage of patients. Pelvic organs opacification allowed us to document not only the normal position of the pelvic organs tested, but also any variations (ranging from 5% to 40% of cases, after pelvic surgery). Furthermore, POO revealed previously not-reported abnormalities in patients undergoing surgery, mostly rectal stenosis, urinary or anal incontinence, and bladder luxation. The cost of the materials used was $10-15 for each POO, and the time required 5-7 min. The side effects were 7% and not significant. CONCLUSION: In the simulation phase for multiple-field irradiation technique, the simultaneous visualization of pelvic organs obtained by POO procedure allows an exact positioning of the isocenter, an accurate shielding of structures, and finally, a reliable conformal therapy. Due to the low cost, the short length, and the insignificant side effects, POO can be carried out more than once during pelvic treatments for localization and verification of target.

External radiotherapy in the treatment of tonsillar carcinomas. Analysis of 183 cases.

A retrospective analysis of 183 consecutive patients with tonsillar carcinoma observed from 1970 through 1984 and treated by external radiotherapy was carried out. The data were analyzed retrospectively to determine the factors affecting prognosis. Tumor size (T) and lymph node involvement (N) were found to be predominant prognostic factors. The difference in 5 year survival rate between T2 and T3 tumors was significant, and that between N1 and N3 was highly significant, whereas difference in survival could be found between N0 and N1 groups. The primary tumor was controlled by radiotherapy alone in 90% of cases of T1 lesions, 58% of T2, 37% of T3 and 11% of T4, and lymph node metastases was controlled in 70% of N1 cases, 0 of N2 and 15.5% of N3. Twenty-three patients underwent salvage surgery after radiotherapy had failed and the actuarial 5 year survival rate was 75% for stage I, 40% for stage II, 30% for stage III and 13% for stage IV.

Non-Hodgkin lymphomas presenting with spinal epidural involvement.

Spinal cord compression was the presenting symptom in 9 out of 299 previously undiagnosed non-Hodgkin lymphomas observed between 1972 and 1987. All patients had unfavourable histologic diagnosis and 4 had stage I E, 2 stage II E and 2 were staged as IV; one patient did not undergo a staging procedure. All patients were treated with surgery and radiotherapy, whereas chemotherapy was employed in 3 cases only. Only 2 patients are still alive and disease-free after 3 and 8 years respectively; the remaining 7 died with progression of disease, even if in 2 cases a complete clinical remission was obtained. The recent literature has been reviewed. Non-Hodgkin lymphoma with spinal epidural presentation is usually an aggressive disease. An intensive treatment combining surgery, radiotherapy and chemotherapy is finally suggested to achieve better local and long-term results. Surgery can as a rule be limited to laminectomy plus biopsy.

Phase III randomized study of fluorouracil, epirubicin, and cyclophosphamide v fluorouracil, doxorubicin, and cyclophosphamide in advanced breast cancer: an Italian multicentre trial.

From February 1983 to January 1985, 497 patients with advanced breast cancer were randomly allocated to receive either epirubicin or doxorubicin in the following combination chemotherapy regimen: fluorouracil (5-FU) 500 mg/m2 intravenous (IV) on days 1 and 8; epirubicin or doxorubicin 50 mg/m2 IV on day 1; cyclophosphamide 500 mg/m2 IV on day 1 (FEC or FAC). Cycles were repeated every 21 days until progression or to cumulative doses of 700 mg/m2 for epirubicin and 550 mg/m2 for doxorubicin. Dose reductions were applied according to the standard criteria. Activity was evaluated in 443 patients (222 in the FEC arm and 221 in the FAC arm). The two experimental groups were comparable in age, performance status, menopausal status, histology, previous treatments, and site of the disease. The overall response rate (complete response and partial response [CR + PR]) was not significantly different: 53.6% for FEC and 56.5% for FAC. The median time to progression was 273 days for FEC and 314 days for FAC; the median survival time was 591 and 613 days, respectively. Leukopenia, anemia, nausea, and vomiting were significantly lower in patients treated with FEC. As for cardiotoxicity, four cases of congestive heart failure (CHF) were recorded among patients treated with FAC while only one was observed in the FEC group. These results indicate that epirubicin in a combination chemotherapy regimen is as active as doxorubicin and is significantly less toxic.

Postoperative management of primary spinal cord ependymomas.

Treatment and final outcome of 11 patients with primary spinal cord ependymomas admitted between 1967 and 1983 have been reviewed. All patients had undergone surgery once or twice before radiation treatment. Six of them are alive and disease-free 78 months to more than 180 months after radiation therapy. A short analysis of the recent literature is presented with special emphasis on the most frequent treatment techniques, extension of radiation fields and doses. The value of postoperative radiation therapy and the complications of both surgery and radiotherapy are analyzed. Some guidelines for treatment are finally discussed and proposed.

Postoperative irradiation of brain ependymomas. Analysis of 33 cases.

Treatment and final outcome of 33 patients with brain ependymoma were reviewed. All patients had been operated, but the surgical removal was incomplete in the great majority of cases. Radiation therapy was subsequently performed using one of the following techniques; a) partial brain irradiation against the primary involved areas in 17 cases, b) whole brain irradiation plus boost against primary involved sites in 6 cases and c) total craniospinal irradiation in 7 cases. Three patients were not eligible for the present study because of underdosage. Five- and 10-year survival rates were 48 and 38% respectively. A short survey of recent literature is presented. The possible causes of failure and the methods for postoperative irradiation are discussed against the background of literature and our own cases.

The role of radiation therapy in the management of primary non-Hodgkin lymphomas of the central nervous system: clinical study of 10 cases.

A series of 10 patients with a primary non-Hodgkin lymphoma of the central nervous system were observed and treated by the authors. All were diagnosed after a pathologic examination of the surgical material; the lesions were supratentorial in all cases and unifocal in 9. In every case radiation therapy improved clinical conditions and in most cases even radiologic features of the patients. Four patients were alive and without evidence of disease many months after therapy. Four patients died with a relapse in the central nervous system; 3 of them had disseminated disease at the time of death. Two patients died for an unknown cause. Radiation therapy was performed with 60Co source with 2 opposed portals and the whole brain irradiation technique in all cases but 2. Doses ranged from 35 to 54 Gy. The recent literature on this uncommon disease and the most adequate therapeutic possibilities of radiation therapy and chemotherapy, or both, are discussed.

Dose evaluation to patients irradiated by 60Co beams, by means of direct measurement on the incident and on the exit surfaces.

A method for direct dose measurements on a patient treated with 60Co beams, is described. A home-made multi-probe dosimeter with silicon diodes as detectors is described. Measurements were performed on the entrance as well as on the exit fields, and a correlation was established with the mid-line dose. The influence of field size, SSD, patient thickness, and inhomogeneities was investigated.

Pharmacologic data and technical feasibility of intraperitoneal doxorubicin administration.

Seventy intraperitoneal administrations of doxorubicin were performed in 12 patients with malignant disease in the abdominopelvic space. Peritoneal and hematologic drug levels were measured by fluorimetric assay. A first-order decline in the peritoneal level was determined (T 1/2 96 +/- 18 min), with a mean drug absorption of 84% in 4 h (range 40-96%) and a mean ratio of a peak dialysate/peak serum level of 111 (range 12-390). Gastrointestinal toxicity was common and peritoneal phlogosis occurred twice. The doxorubicin level and the time of peritoneal exposure seem to be critical factors for major local toxicity. At a moderate concentration doxorubicin can be intraperitoneally administered, but its usefulness is probably confined to patients with minimal abdominal disease.

Pharmacological data and technical feasibility of intraperitoneal 5-fluorouracil administration.

Via a surgically implanted Tenckhoff catheter, 5-fluorouracil was intraperitoneally administered to patients with malignant disease confined to abdominal space. Treatment was well tolerated without local complications. Peritoneal and plasmatic drug levels were measured, showing that: 1) peritoneal drug levels declined as a first order function; 2) plasmatic levels were very close to those reported for continuous i.v. administration, but peritoneal concentrations were much higher (log 1 to 3); 3) concentration x time product had a peritoneum: plasma ratio ranging from 120 to 1350. The hypothesized role of intraperitoneal 5-fluorouracil administration and the questions still to be answered are summarized.

[Approach to the problem of economic costs of the medical therapy of tumors]. / Approccio al problema dei costi economici della terapia medica dei tumori.

The use of antitumoral drugs is increasing constantly. The economic cost pro capite of the commonest oncotherapeutic treatments has been analysed. The calculation is carried out on the basis of out-patient as well as in-patient treatment. The costs were identical in the hospital where the study was carried out due to the application of the recent regional health legislation. A number of considerations are made regarding the implications of unqualified use of the medical treatment of cancer.

A new CMF regimen.

In CMF regimen, gastric disturbances secondary to oral administration of cyclophosphamide (CTX) frequently induce many patients to take the drug erratically, to lower the daily dose, or to divide it in many administrations. These alterations act as a source of uncertainty in the evaluation of treatment results and may decrease the chemotherapy effectiveness. An i.v. CTX administration is proposed, and the rationale of such a proposal in examined. Data on the mild toxicity of the new schedule are reported.