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.

Clinical and economic considerations in the treatment of acute exacerbations of chronic bronchitis.

Limited data exist to guide physicians in the cost-effective treatment of acute exacerbation of chronic bronchitis (AECB). Therefore, the main objective of this study was to determine the antimicrobial efficacy and related costs for patients with AECB. A retrospective review of 60 outpatient medical records with a diagnosis of chronic obstructive pulmonary disease (COPD) and chronic bronchitis episodes from a pulmonary clinic of a teaching institution was undertaken. The participating patients had a total of 224 episodes of AECB requiring antibiotic treatment. Before review, empirical antibiotic choices were divided into first-line (amoxycillin, co-trimoxazole, tetracyclines, erythromycin), second-line (cephradine, cefuroxime, cefaclor, cefprozil) and third-line (co-amoxiclav, azithromycin, ciprofloxacin) agents. Patients receiving first-line agents failed significantly more frequently than third-line agents (19% vs 7%, P < 0.05). Additionally, patients prescribed first-line agents were hospitalized significantly more often for AECB within 2 weeks of outpatient treatment as compared with patients prescribed third-line agents (18.0% vs 5.3% third-line agents; P < 0.02). Time between subsequent AECB episodes requiring treatment was significantly longer for patients receiving third-line agents compared with first-line and second-line agents (P < 0.005). Pharmacy costs were lowest with first-line agents (first-line US$10.30 +/- 8.76; second-line US$24.45 +/- 25.65; third-line US$45.40 +/- 11.11; P < 0.0001), but third-line agents showed a trend towards lower mean total costs of AECB treatment (first-line US$942 +/- 2173; second-line, US$563 +/- 2296; third-line, US$542 +/- 1946). The use of third-line antimicrobials, co-amoxiclav, ciprofloxacin or azithromycin, significantly reduced the failure rate and need for hospitalization, prolonged the time between AECB episodes, and showed a lower total cost for the management of AECB. Prospective studies are needed to confirm these findings.

A study on neonatal calf diarrhea induced by rotavirus.

This review summarizes the results of a study on rotaviruses isolated from calves affected by neonatal diarrhea. The results indicated that rotavirus infection is widespread and supported the evidence for an etiologic role of these viruses in neonatal diarrhea. Differences in virulence among bovine rotaviruses appeared also to be confirmed. Conventionally reared calves were fully susceptible to the experimental infection induced by rotaviruses originating from heterologous hosts, i.e. monkeys, pigs and rabbits. When rotavirus strains of bovine, simian and rabbit origin were compared by cross neutralization tests, it was found the simian and porcine strains were indistinguishable and both appeared to relate antigenically to the bovine strain. Finally, it was proven that feeding newborn calves with colostrum and first milk of their dams, previously vaccinated with an inactivated adjuvanted rotavirus vaccine, could prevent the neonatal diarrhea from occurring.

Field evaluation of the efficacy of Romovac 50, a new inactivated, adjuvanted bovine rotavirus vaccine.

An inactivated bovine rotavirus vaccine, prepared with an adjuvant which gives a water-in-oil emulsion (Montanide ISA 50, adjuvant) was used in field trials for prevention of calf neonatal diarrhoea. The vaccine, which was designated as Romovac 50, when injected into cows in their last month of pregnancy, proved to be as effective as the traditional vaccine prepared with Freund's incomplete adjuvant. Thus, the incidence of the naturally occurring neonatal diarrhoea was significantly reduced in calves which were fed mammary secretion from their vaccinated dams, compared to the calves delivered from the unvaccinated cows. Romovac 50 also has the advantages over the traditional Freund's adjuvanted vaccine in that it is less viscous and thus more readily injected and less irritant to tissues.

Cystic and bullous lung disease.

One of the most difficult problems facing clinicians is the evaluation and management of patients with dyspnea whose chest roentgenogram shows single or multiple large cystic spaces. This is made more difficult when underlying lung disease is present. The dilemma focuses on whether the obliteration or removal of the cystic areas will benefit or cause further deterioration of the patient's condition. The pathophysiology of the problem is not completely understood, but accumulated clinical experience has shown that surgical therapy can be beneficial but requires proper patient selection.

Immunization against bovine rotaviral infection.

Calves fed with colostrum from cows vaccinated with an inactivated rotavirus vaccine were refractory to experimental infection with strain 81/36F of bovine rotavirus. In the field study, 458 pregnant cows from 26 herds were involved. In each herd, cows were selected and randomly subdivided in two groups. Cows in one group (248 head in total) were vaccinated, whereas cows in the other group (210 head in total) were left as unvaccinated controls. At calving, colostrum was collected from each cow and stored at -30 degrees C until used for feeding calves. The newborn calves, beginning the second day of life and for the next 7-10 days, were each fed a daily supplement of 400 ml of colostrum from its dam. The diarrhea occurred in 86 (40.9%) calves that had received colostrum from unvaccinated dams (normal colostrum), and in 7 (2.8%) calves which were fed colostrum from vaccinated dams (immune colostrum). The disease was very severe in the normal colostrum-fed calves and 52 of them died. By contrast, the 7 immune colostrum-fed calves displayed a rather mild enteric condition, and all recovered without any sequela being observed.

Equations for the prediction of resting energy expenditure in chronic obstructive lung disease.

Resting energy expenditure can be obtained either by indirect calorimetry or from prediction equations. Several prediction equations were compared to the measured value of REE in a group of COPD patients with moderate to severe disease. Then, using the same group of patients, a new equation was derived by regression analysis and was prospectively tested on patients with similar characteristics. Equations derived from normal populations (Harris-Benedict, Wilmore nomogram) were shown to underestimate REE by 300-400 Kcal. Equations that use body weight as the only variable were found to be easier to use and did not appear to sacrifice accuracy. Quebbeman Ausman body weight, Quebbeman Ausman body surface area and a regression equation derived from COPD patients (males, REE = 11.5 x wt [kg] + 952; females, REE = 14.1 x wt [kg] + 515) performed better than other currently used equations. In both stable COPD and COPD with exacerbation, the mean predicted values fell within a standard deviation (+/- 167 Kcal) of measured values.

Field trial evaluation of an inactivated rotavirus vaccine against neonatal diarrhea of calves.

Field trials were conducted using an inactivated rotavirus vaccine for prevention of calf neonatal diarrhea. For the trials, 458 pregnant cows from 26 herds were involved. In each herd, cows which had been inseminated within a period of two months were selected and randomly subdivided in two groups. Cows in one group (248 head in total) were vaccinated 6 weeks before calving and again 4 weeks later; cows in the other group (210 head in total) were left as unvaccinated controls. At calving, colostrum was collected from each cow and stored at -30 degrees C until used for feeding calves. The newborn calves, beginning the second day of life and for the next 7-10 consecutive days, each was fed a daily supplement of 400 ml of colostrum from its dam. The diarrhea occurred in 86 (40.9%) calves that had received colostrum from unvaccinated dams (normal colostrum), and in 7 (2.8%) calves which were fed colostrum from vaccinated dams (immune colostrum). The disease was very severe in the normal colostrum-fed calves and 52 of them died. Those calves which survived the disease underwent a significant loss of condition. By contrast, the 7 immune colostrum-fed calves displayed a rather mild enteric condition, and all recovered without any sequela being observed.

Recurrent cavitary nodules secondary to Hodgkin's disease.

A patient with nodular sclerosing Hodgkin's disease had at least three episodes of lung involvement consisting of an infiltrate on one occasion and multiple cavitating nodules on the other two. The cytologic and histologic studies of the lung specimens disclosed the presence of Reed-Sternberg cells on each occasion without any evidence for infection. This represents the first time in which recurrent cavitating nodules have been reported with Hodgkin's disease.

Catamenial pneumomediastinum.

A patient with known pelvic endometriosis suffered from recurrent episodes of retrosternal pain in the chest at the time of menstruation. Evaluation during an episode revealed subcutaneous emphysema of the neck and a pneumomediastinum without pneumothorax. This is the first report in the English literature of pneumomediastinum due to endometriosis which was probably recurrent.

Persistent hypoxemia due to patent foramen ovale in a patient with adult respiratory distress syndrome.

This report describes a patient in the recovery phase of the adult respiratory distress syndrome in whom the persistence of severe hypoxemia was not corrected by a high fractional concentration of oxygen in the inspired gas and positive end-expiratory pressure. A right-to-left interatrial shunt was diagnosed by M-mode and cross-sectional echocardiography with saline injection, and the presence of a patent foramen ovale was confirmed at the time of cardiac surgery.

Effects of low and high carbohydrate feedings in ambulatory patients with chronic obstructive pulmonary disease and chronic hypercapnia.

In a randomized, double-blinded study, patients with chronic obstructive pulmonary disease and hypercapnia were fed low, moderate, and high carbohydrate diets to determine the effect on metabolic and ventilatory values. The low carbohydrate diet consisted of 28% carbohydrate calories and 55% fat calories and resulted in significantly lower production of CO2 (p less than 0.002), respiratory quotient (p less than 0.001), and arterial Pco2 (p less than 0.05). At the end of the 15-day study, both the forced vital capacity (p less than 0.05) and the forced expiratory volume in 1 second (p less than 0.05) had improved by 22% over baseline values. Total calories given surpassed daily caloric requirements. This approach, together with a low carbohydrate, high fat mixture, may be beneficial for such patients.

Evaluation of dyspnea. Is it really present and, if so, why?

Subacute or chronic dyspnea can be one of the most difficult complaints to evaluate. Dyspnea may represent the complaint of a person who is poorly fit, one who is suffering from anxiety or from some organic dysfunction, or one who is looking for secondary gain. The objectives in evaluating these patients are to determine that dyspnea is truly present and, if it is, to diagnose the specific cause so appropriate treatment can be undertaken. Often a good general evaluation is definitive enough to direct the clinician to specific tests that reveal the underlying cause of dyspnea. Some patients, however, require specialized tests both to confirm dyspnea and to indicate specific organic dysfunction.

Technical problems in pancreatoduodenectomy.

This paper reports on technical problems involved in pancreatoduodenectomy. Twenty cases of periampullary carcinoma underwent pancreatoduodenectomy. Pancreatic fistula developed in five cases: three of these patients recovered using simple drainage and TPN; one underwent a second operation in which a new pancreatico-jejunostomy was performed and another patient died (5% of the series) from sepsis and liver failure. After reviewing various techniques used in performing pancreatico-jejunostomy, it is concluded that the most suitable management of the pancreatic stump seems to be the duct-to mucosa anastomosis. But in cases in which this type of reconstruction is impossible, invagination yields satisfactory results.