Biopharmaceutical profile of diclofenac-misoprostol combination tablet, Arthrotec. Arthrotec, a combination tablet has been developed that contains 50 mg of diclofenac in an inner core and 200 micrograms of misoprostol in an outer mantle. Both diclofenac and misoprostol are extensively absorbed and their maximum plasma concentrations, but not total availability, are diminished when taken with food. Both drugs have elimination half-lives of less than 2 hours and do not accumulate in plasma after recommended doses. Pharmacokinetic and bioavailability studies of the combination product taken separately and together reveal a high between- and within-subject variability in plasma diclofenac levels, especially when the enteric-coated tablets were given after food; reliable values for peak plasma diclofenac concentration could not be ascertained. No pharmacokinetic interactions between diclofenac and misoprostol were apparent. The bioavailability of diclofenac and misoprostol from the combination tablet was similar to that seen when the two drugs are given separately.


The economic consequences of NSAID-induced gastropathy: the French context. The costs of treating gastroduodenal ulcers caused by nonsteroidal anti-inflammatory drugs (NSAIDs) are shown to increase the total cost of NSAID treatment to the Assurance-Maladie, the French national health insurance system. This increased cost is termed the iatrogenic cost factor, and is defined as the ratio of the shadow price of an NSAID to its reimbursed cost. The shadow price is calculated from estimates of the incidence of NSAID-induced gastropathies, the cost of the drug, and the hospital and ambulatory costs of treating the gastropathies. The resulting iatrogenic cost factors are estimated as 1.36 for naproxen, 1.48 for sulindac, 1.65 for diclofenac, 1.67 for piroxicam, 2.00 for ketoprofen, and 2.12 for etodolac.


The economic consequences of NSAID-induced gastropathy in the United Kingdom and commentary on the article by G. de Pouvourville. The iatrogenic cost factor of treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) is defined as the increase in cost resulting from NSAID-induced gastroduodenal ulcers. The iatrogenic cost factor of NSAIDs for the National Health Service (NHS) in the United Kingdom was calculated using the model of de Pouvourville (1992). The cost factor is defined as the ratio of the shadow price of the NSAID to the NHS price. The shadow price is calculated from the incidence of NSAID-induced gastroduodenal ulcers and the costs of treating them and the price of the drugs. The NHS iatrogenic cost factors of 10 NSAIDs were similar to those calculated by de Pouvourville for the French national health insurance system, Assurance-Maladie, and ranged from 1.08 for diclofenac/misoprostol to 2.38 for ibuprofen.


Efficacy of Arthrotec in the treatment of rheumatoid arthritis. In a double-blind study, 346 patients with active rheumatoid arthritis were randomly assigned to receive Arthrotec, a combination of 50 mg of diclofenac and 200 *g of misoprostol, or 50 mg of diclofenac; the drugs were given two or three times daily for 12 weeks. At weeks 4, 8, and 12 of treatment, no clinically significant differences between the two treatment groups were noted on measures of joint tenderness, pain, and swelling or on physicians' and patients' assessments of disease severity.


Endothelial cell destruction by polymorphonuclear leukocytes incubated with sera from patients with systemic lupus erythematosus (SLE). When normal polymorphonuclear leukocytes (PMN) were incubated with sera from patients with active systemic lupus erythematosus (SLE), a significantly increased cytotoxicity against human cultured vascular endothelial cells (EC), compared with normal control sera, was demonstrated by the standard 51Cr release method. The degree of this cytotoxicity was correlated with the immune complex level in each serum. The cytotoxicity did not correlate with the presence of anti-EC antibody. An absorption study with C1q-Sepharose 4B further suggested that the immune complexes are the factor which induce cytotoxicity. A gel fractionation study, however, indicated the heterogenity of the cytotoxic activity, and suggested the possible contribution of other substances including anti-EC, at least in some of the patients. This type of cytotoxicity may initiate the inflammatory process including vascular damage of the disease.


Morphological evidence for biological control of urate crystal formation in vivo and in vitro. Urate crystal formation, and subsequent gout, occurs in only a minority of hyperuricaemic subjects indicating that factors other than hyperuricaemia are involved. Biological substances (especially proteins) alter crystal growth in vitro independently of uric acid concentration. Physiological crystal formation, known to be under biological control, is characterised morphologically by uniformity of size and constraint of crystal shape. To determine whether pathological urate crystal formation is influenced by the surrounding biological milieu we examined, using scanning electron microscopy, the morphology of urate crystals formed either in vivo or in vitro. We found morphological evidence of biological control of in vivo urate crystal formation and demonstrated that those characteristics could be induced in vitro by the addition of serum, synovial fluid and certain serum proteins to the growth medium during crystal formation. Urate crystal formation is dependent, not only on the degree of hyperuricaemia, but also on the surrounding biological milieu.


Nailfold capillary permeability in psoriatic arthritis. This study is the first report of the permeability status of nailfold capillaries in psoriatic arthritis (PA). "Traditional" nailfold capillary microscopy and intravital fluorescence videomicroscopy were carried out at the nailfold of 13 patients with PA. Twenty five healthy subjects served as controls for nailfold capillary microscopy, and 15 out of these for fluorescence videomicroscopy. The following parameters were assessed: capillary length, apex width, maximum loop width, maximum limb width, loop density, visibility of subpapillary venular plexus, loop tortuosity, transcapillary diffusion, and interstitial concentration at different sites and times of Na-fluorescein given in intravenous bolus. Morphometric analysis of capillaroscopic findings showed a significant increase of loop length (mean +/- SD: 290.1 +/- 73.5 microns) when compared to healthy controls (223.3 +/- 51.9 microns) (P < 0.02). Transcapillary passage of Na-fluorescein was homogeneous and symmetric both in PA patients and in controls. Mean transcapillary and interstitial diffusion was not significantly enhanced at the nailfold in PA patients. Our data support the view that PA is not characterized by a specific capillaroscopic pattern and/or significant abnormalities of microvascular dynamics at the nailfold.


Validation of a Swedish version of the Arthritis Self-efficacy Scale. The purpose of this study was to test the validity of a Swedish Version of the Arthritis Self-efficacy Scale on two groups of patients: 25 patients with chronic pain and 24 rheumatology patients. Scores on the three subscales of the self-efficacy instrument--for controlling pain, for controlling function of daily living activities, and for controlling other symptoms--were correlated with indicators of present pain status and scores on the Multidimensional Health Locus of Control Scales. All correlations were in the direction predicted by self-efficacy theory, providing evidence for the construct validity of the scale. In addition the two patient groups differed significantly on the three subscales indicating evidence for the discriminant validity of the instrument.


Long-term evaluation of penicillamine or cyclofenil in systemic sclerosis. Results from a two-year randomized study. In a two-year prospective therapeutic trial 13 patients with systemic sclerosis (SSc) were treated with penicillamine, 9 with cyclofenil, and 7 with neither. At entry skin involvement and esophageal, lung, heart, and kidney function did not differ significantly between the groups. Reevaluation after one and two years did not show any significant changes in skin, esophageal, heart, and kidney manifestations, while lung function had slightly improved in both drug-treatment groups. This study thus shows little overall effect of penicillamine and cyclofenil, although both drugs may arrest worsening of pulmonary dysfunction.


Sensitivity to UV light during treatment with chloroquine in rheumatoid arthritis. Chloroquine and hydroxychloroquine have long been suspected of causing light sensitivity in patients with rheumatoid arthritis (RA). To gain insight into the effect of chloroquines and ultraviolet (UV) light in RA we have phototested 25 RA patients with and without chloroquine. The thresholds for UVA and UVB did not change upon treatment with chloroquine or hydroxychloroquine. Provocation with high dose UVA and UVB was similar with and without treatment with chloroquine or hydroxychloroquine. Our results have shown that photosensitivity during medication with chloroquine and hydroxychloroquine is uncommon and that there is no need to stop this treatment due to sun exposure.


Long-term blood flow potentials in sequential internal mammary artery grafts. Exercise thallium scan for myocardial perfusion study. In two groups of patients, coronary artery bypass surgery for angina pectoris included internal mammary artery (IMA) sequential grafts (group I) or single grafts (group II). At postoperative angiography all grafts were patent. In addition, the patients received on average 1.8 vein grafts into other coronary arteries. The mean interval to postoperative follow-up was 9.5 years in group I and 9.7 years in group II. The preoperative incidence of acute myocardial infarction was 44% and 45% in groups I and II. Exercise thallium scan at follow-up showed IMA graft-related ischemia in 33% of the patients with sequential graft and in 64% of those with single graft (ns). Our results indicated that sequential IMA grafts functioned at least as well as single grafts and maintained adequate myocardial supply even 10 years postoperatively. Internal mammary arteries are superior graft material and can be recommended both as single and as sequential graft in coronary artery bypass surgery.


Surgical treatment of myocardial bridging causing coronary artery obstruction. Nine patients with obstruction of coronary artery blood flow caused by myocardial bridging underwent surgery after failure of medical treatment. The diagnoses were made angiographically at rest or during beta-stimulation. Impaired blood flow was found only in the left anterior descending artery in seven patients and additionally in the diagonal branch in two. The operations, performed with cardiopulmonary bypass consisted of complete dissection of the overlying myocardium. All patients survived the operation. Major intraoperative complications were accidental opening of the right ventricle in two patients. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation. Surgical relief of myocardial ischemia due to systolic compression of intramyocardial coronary arteries can be accomplished with low operative risk and with excellent functional results.


Hemodynamic effects of intraaortic versus intravenous protamine administration after cardiopulmonary bypass in man. A hemodynamic study of men undergoing elective coronary artery bypass surgery was undertaken to elucidate the side effects of protamine given into the ascending aorta (group A, n = 16) or into the central venous line (group V, n = 16). After termination of extracorporeal circulation, protamine was infused over 120 seconds, and the hemodynamic profile was continuously recorded. During the first minute, the systemic arterial pressure fell to about 60% of the preprotamine level in both groups, but the hemodynamic changes occurred more rapidly (p < 0.05) in group V than in group A, with maximal pressure drop at 61.7 +/- 2.7 vs 74.4 +/- 4.9 seconds. Following spontaneous restoration of the systemic blood pressure, the pulmonary artery pressure rose considerably in both groups, as did the pulmonary capillary wedge and central venous pressures, reaching higher levels in the intravenous group. The cardiovascular responses were again more rapid in group V than in group A (p = 0.004). The degree of systemic hypotension thus did not benefit from use of the intraaortic rather than the intravenous route for administering protamine. The more pronounced and more rapid pulmonary circulatory changes in the intravenous group suggest that the hemodynamic effects of protamine are initiated in the lungs.


Motility studies of the cervical esophagus with intrathoracic gastric conduit after esophagectomy. Gastric emptying, upper esophageal sphincter pressure and intrathoracic gastric motility were studied in esophagectomized patients, ten with a gastric conduit in the posterior mediastinum and ten with a conduit in the retrosternal space. In addition, the clinical state was reassessed more than 6 months after esophageal reconstruction. Gastric emptying, assessed with Tc-99m Sn colloid in a semisolid test meal, did not differ between the two groups. In manometric studies a high-pressure zone distal to the upper esophageal sphincter was associated with dysphagia. A high-pressure zone at the anastomosis was found in 60% of the retrosternal group and 20% of the posterior mediastinal group. As regards food intake, the posterior mediastinal route seems to be preferable in esophageal replacement, since it permits more physiologic motility of the conduit.


Suture closure versus stapling of bronchial stump in 304 lung cancer operations. Suture closure of the bronchial stump was compared with staple closure after 304 operations for bronchogenic carcinoma over an 8-year period. In 154 cases (112 lobectomies and 42 pneumonectomies) the bronchial stump was closed with interrupted sutures of 000 polyester, and in 150 cases (120 lobectomies and 30 pneumonectomies) an autosuture stapler was used. The time for suture closure ranged from 5-15 minutes, whereas stapling was accomplished uniformly in c. 90 seconds. Bronchopleural fistula developed after suture closure in seven cases (4.5%), but in none after stapling closure. Stapling of the bronchial stump after lobectomy or pneumonectomy for lung cancer is safer and quicker than suture closure, and is recommended as the method of choice.


Surgical treatment of stage III non-small cell bronchogenic carcinoma involving the chest wall. Thirty-five patients who had undergone surgery for non-small cell bronchogenic carcinoma with isolated involvement of the chest wall were reviewed. The diagnosis was preoperatively suspected in 80% of cases. En-bloc resection of the invaded chest wall was performed in 25 cases and parietal pleurectomy in ten in which the pleura was easily dissectable from the costal plane. Of the eight patients with major complications in the early postoperative period, six, including the two who died perioperatively, had undergone en-block resection. The 5-year actuarial survival rate was 22% overall and 36% in the patients without lymph node involvement. No significant relationship between survival and type of operation or degree of chest wall invasion was found. Isolated involvement of the chest wall by non-small cell bronchogenic carcinoma does not necessarily contraindicate surgery with curative intent. Parietal pleurectomy is valid in selected cases. Long-term survival depends basically on node involvement.


In vitro responses to atrial natriuretic polypeptide in human vessels commonly used as aortocoronary bypass grafts. Vascular effects of atrial natriuretic polypeptide (APII), i.e. the peptide hormone released from the atrial myocardium, were investigated in segments of the human internal thoracic artery (ITA) and saphenous vein (SV) with intact (+E) or injured (-E) endothelium. All segments were subject to several cycles of agonists in order to detect tachyphylactic or facilitatory responses. Opposite, indirect effects on the noradrenaline contracted ITA and SV were obtained in response to APII at a supranormal concentration (50 nM) which had no direct relaxing action on the isolated segments in vitro. In ITA the noradrenaline contractures in subsequent cycles were reduced to 41 +/- 21% (+E) and 28 +/- 9% (-E), but in SV they were enhanced to 211 +/- 115% (+E) and 483 +/- 242% (-E) of those before APII exposure. Thus under in vitro conditions ITA could be indirectly relaxed by APII via tachyphylactic effect on the noradrenaline contracture. SV, on the other hand, was markedly potentiated by APII in its noradrenaline response. In injured endothelium these opposite effects were aggravated.


Efficacy of phosphodiesterase inhibitor enoximone in management of postcardiotomy cardiogenic shock. The efficacy of the phosphodiesterase inhibitor enoximone for reversal of severe postcardiotomy low cardiac output syndrome was investigated in 13 cases of cardiogenic shock refractory to conventional treatment consisting of beta-adrenergic agonists (n = 13) combined with vasodilators (n = 7), and intra-aortic balloon counterpulsation (n = 5). Following a bolus of 1 mg/kg enoximone, cardiac and stroke volume indices increased from 1.56 +/- 0.27 l/min/m2 and 16.3 +/- 3.3 ml/m2, respectively, to 2.72 +/- 0.67 and 27.8 +/- 7.1 (both p < 0.001). Mean arterial pressure fell, from 77 +/- 11 to 68 +/- 9 mmHg (p < 0.05), as did atrial filling pressures (LAP and RAP), LAP from 21.3 +/- 5.5 to 15.9 +/- 2.9 and RAP from 16.6 +/- 2.3 to 13.7 +/- 2.1 mmHg (both p < 0.01). The heart rate rose by only 5%. Enoximone therapy was maintained by a continuous infusion (5-7.5 micrograms/kg/min) for 40.6 +/- 8.6 hours (range 14-92). All hemodynamic parameters remained stable throughout treatment. Six patients died of sepsis and/or multiorgan failure but seven were discharged from hospital. Enoximone thus improved hemodynamic performance significantly in cardiogenic shock after open-heart surgery. It also has proved valuable in cardiac failure when conventional therapy was unsuccessful.


Effect of acid-base management with or without carbon dioxide on plasma phosphate concentration during and after hypothermic cardiopulmonary bypass. Variations of the phosphate concentration in plasma were studied in two groups of 12 patients undergoing cardiac surgery with hypothermic cardiopulmonary bypass (CPB). Management of the acid-base status differed between the groups, according to whether or not carbon dioxide was added to the anesthetic gas mixture during hypothermia ('pH-stat' vs. 'alpha-stat' mode) following correction vs. no correction of pCO2 and pH for body temperature. Phosphate variations throughout the study were mostly within normal limits. From the start to the end of CPB, the mean rise in phosphate levels was 70% in the pH-stat group and 37% in the alpha-stat group (p < 0.001). During 3 hours after CPB, the phosphate values continued to rise by a mean of 25% in the alpha-stat patients, but fell by a mean of 3% in the pH-stat patients (p < 0.001). Such different phosphate patterns during and immediately after CPB may reflect profound metabolic disturbances and may be related to the altering effects of CO2 addition and respiratory acidosis on intracellular metabolic activity and phosphate homeostasis.


Successful surgical management of rupture of the left ventricle and interventricular septum due to blunt chest trauma. Case report. In a 35-year-old man blunt chest trauma caused rupture of the free wall of the left ventricle and the interventricular septum. Emergency pulse Doppler-2D echocardiography confirmed the clinical suspicion and immediate surgical repair was successfully undertaken. This appears to be the first reported case of survival after surgery for such combined cardiac rupture.


Carcinosarcoma of the lung with gastrointestinal metastasis. Case report. An unusual case of carcinosarcoma of the lung with metastasis to the gastrointestinal tract causing intussusception is presented. The clinical, radiologic and histopathologic features are reviewed with reference to relevant literature.


Dimensions of the heart and great vessels in normal children. A postmortem study of cardiac ventricles, valves and great vessels. Knowledge of normal heart dimensions is often needed in the planning of cardiac surgery in children. Attempts to define 'normal' have so far given varied and somewhat controversial results. The purpose of this study was to determine normal values for all heart measurements of clinical importance in children. Special interest was focused on the relationship between the diameters of the right and the left pulmonary artery (RPA abd LPA) and the descending thoracic aorta (DTA), defined as RPA/DTA+LPA/DTA, which is widely used in evaluating the feasibility of certain pediatric cardiac operations. The normal curve of this ratio during growth has not previously been presented in the literature. The observed data provide reliable normal values for the diameters of the great vessels and valves and the ventricular volumes of the heart.


Ductus arteriosus in pulmonary atresia with and without ventricular septal defect. Anatomic and functional differences. The pulmonary circulation is dependent on the ductus arteriosus in all patients with pulmonary atresia and intact ventricular septum and in some with pulmonary atresia and ventricular septal defect (tetralogy of Fallot type). To assess the time of ductal closure in these two patient categories, we compared the ages at first operation in 58 patients with pulmonary atresia and intact ventricular septum and 32 with pulmonary atresia and septal defect. The age distribution differed significantly between the groups. Whereas 90% of the children with intact ventricular septum required surgery in the first week of life, 50% of those with ventricular septal defect underwent surgery after the first month and 25% after the third month. The previously described and now confirmed anatomic differences of ductus arteriosus or different levels of endogenous prostaglandins may explain persistent patency of the ductus in pulmonary atresia with ventricular septal defect. The phenomenon may have important clinical implications regarding the timing and choice of surgical procedure.


Open-heart surgery in patients requiring chronic hemodialysis. The management and outcome of open-heart surgery in 31 patients requiring chronic hemodialysis because of end-stage renal failure are reviewed. The reasons for surgery were coronary artery disease (20 cases), mitral valvulopathy (5, including 3 with tricuspid insufficiency), aortic valvulopathy (5, including 2 with coronary artery disease) and perforation of an aortic aneurysm into the left upper lung lobe. Surgery was elective in all but the last case. Apart from double venous cannulation to avoid potassium overload after cardioplegia, and hemofiltration in the extracorporeal circulation permitting removal of 1,500-2,000 ml fluid during bypass, procedure was routine. Postoperatively fluids were restricted and serum potassium levels were not allowed to exceed the known preoperative maximum. Four patients required catecholamine support for 3-10 hours. Thirty were weaned from the respirator after 8-41 (mean 16) hours. The one perioperative death was due to complications associated with post-bypass administration of protamine. Dialysis was restarted 20-69 (mean 32) hours postoperatively. With appropriate management of fluid balance and potassium, open-heart surgery in dialysis-dependent patients need not carry heightened risk.


Problems and perspectives in the identification of new occupational carcinogens. Occupational studies have played a major role in the identification of chemical carcinogens. There still remain, however, substances and occupations that deserve further evaluation. The more careful control of potentially hazardous exposures in most developed countries has necessitated a change in the conduct of epidemiologic investigations. The lowering of exposures and the lack of a simple correspondence between specific exposures and one or a few jobs underscores the need for careful reconstruction of historical exposures. The most successful reconstructions will include the integration of monitoring data, historical information on work histories and work practices, and use of biochemical markers.


Lung cancer mortality among workers in the European production of man-made mineral fibers--a Poisson regression analysis. One hundred and eighty-one lung cancer deaths among workers during 301,085 person-years in European man-made mineral fiber production between 1930-1955 and 1982 were analyzed according to Poisson regression models including age, calendar period, country, and exposure variables. Time since first employment was the variable most strongly associated with lung cancer risk in both the rock-slag wool and glass wool subcohorts. Workers in the early technological phase were at higher risk than those in other categories, particularly in rock-slag wool production. No clear trend with duration of employment was suggested. No major changes occurred in the interpretation of the results when workers with less than one year of employment or less than 20 years since first exposure were excluded. The original results, based on analyses for standardized mortality ratios, were confirmed, and workers with a short duration of employment or a short time since first employment did not need to be excluded from the analysis.


Oral, pharyngeal and laryngeal cancer as a cause of death among Swiss cooks. In an analysis of Swiss mortality data (1979-1987) excess mortality due to oral, pharyngeal and laryngeal cancer was found among cooks, and the rate was very high in the age group < 55 years. The peak number of cases was observed among cooks in the age category 45-49 years. In the standard population the highest number of such deaths was observed between 65 and 69 years of age. The numbers of alcohol-related causes of death were also elevated among the cooks, while the numbers of smoking-related deaths were not. Although the dominant role of combined alcohol and tobacco consumption for the development of oral, pharyngeal and laryngeal cancer has been confirmed by many studies, other factors (eg, volatile carcinogenic compounds formed during the cooking process) may contribute to the excess mortality from oral, pharyngeal and laryngeal cancer among cooks. The question of the relevance of such factors will have to be answered by further studies.


Work-related electrical fatalities in Australia, 1982-1984. Work-related electrical fatalities were studied as part of a larger investigation into all work-related fatalities in Australia in the period 1982-1984. The 95 electrical fatalities (all men) represented an incidence of 0.49 per 100,000 persons (0.79/100,000 men) in the employed civilian labor force during the study period. Electricity was the fifth highest cause of work-related fatalities in Australia and resulted in 10% of all workplace deaths. Ninety-four percent of the workers were performing their usual tasks at the time of their death, and 38% of them were doing work of an electrical nature at the time. The greatest number of deaths occurred on farms and nonconstruction industrial sites, with overhead powerlines as the main source of current. Better placement of overhead powerlines, improved worker awareness of electrical hazards, and the use of residual current devices would probably have prevented most of the deaths.


Fecundity and the use of video display terminals. The association between prolonged waiting time to pregnancy and the use of a video display terminal (VDT) was investigated among commercial and clerical employees in Denmark. Information on 24,352 pregnancies was obtained through register linkage with two national registers. A random sample of 2252 pregnancies was drawn, and the women were asked for information on waiting time to pregnancy, occupational exposures, and life-style factors. The overall exposure to a VDT indicated a slightly increased association with prolonged waiting time to pregnancy. The relative risks for waiting more than one year were 1.23, 0.77, and 1.61 for the women who worked with a VDT for 1-10, 11-20, and > or = 21 h per week, respectively. Only the last relative risk was statistically significant. The results could be explained by methodological shortcomings such as recall bias or confounding by alternative factors that might affect time to pregnancy, or simply by the lack of statistical power.


Menstrual-cycle characteristics and work conditions of workers in poultry slaughterhouses and canneries. The food and agriculture industry employs 14.6% of the female industrial work force in France. Workers are exposed to a variety of environmental and organizational constraints (eg, irregular schedules, cold, uncomfortable postures, repetitive movements). In 1987-1988 a medical examination and questionnaire were administered to 726 workers with menstrual periods in 17 poultry slaughterhouses and six canning factories. Anomalies (irregular cycles, amenorrhea, long cycles) during the previous year were associated with work conditions. After adjustment for relevant nonoccupational variables, irregular cycles were significantly related to schedule variability and cold exposure, amenorrhea was associated with cold exposure, and long cycles with schedule variability. Other parameters such as repetitive work, standing posture, lifting weights, job satisfaction, and hours of domestic work were not associated with cycle anomalies. Cycle anomalies may be a useful indicator of occupational effects on female reproduction, analogous to the use of sperm parameters to warn of effects on male workers.


Knee disorders in carpet and floor layers and painters. In an evaluation of the effect of kneeling work on the knees, 168 actively working carpet and floor layers and 146 house painters were examined with the aid of a questionnaire, a clinical examination, and radiography. Reported knee pain, knee accidents, and treatment regimens for the knees were more common among the carpet and floor layers than among the painters. Radiographic changes of the tibiofemoral joint were noted equally in the two occupational groups, but osteophytes of the patella were more common among the carpet and floor layers than among the painters. In a multivariate analysis, the determinants of osteophytosis of the knee were age, occupation, knee accidents, and smoking, and osteophytosis may be due to more frequent workbreaks from kneeling postures among smoking workers. This study indicates that kneeling work increases the risk of knee disorders and such radiographic changes that might be an initial sign of knee degeneration.


Biological monitoring of occupational exposure to low levels of benzene. To obtain reference values for the biological monitoring of benzene, the kinetics of benzene were studied in volunteers. Benzene in blood and expired air could easily be followed until the next morning after a 4-h exposure to a benzene concentration of 10 cm3.m-3. Even after exposure to 1.7 cm3.m-3 the benzene levels in the morning blood and expired air samples differed from those in unexposed subjects. One hour after exposure to 10 and 1.7 cm3.m-3 the mean levels of benzene were 238 and 25 nmol.l-1 in blood and 13.2 and 2.5 mumol.m-3 in exhaled air, respectively. It was concluded that, at high benzene levels (approximately 10 cm3.m-3), samples collected 16 h after exposure reflect the body burden of benzene, while at low exposure (< 1 cm3.m-3) samples collected 1 h after exposure may be used to estimate the exposure over the preceding few hours. Exposure to benzene from smoking is a potential confounder in estimating occupational exposure to low levels of benzene.


Tetanus caused by occupational accidents. The role of occupational accidents as a source of tetanus is poorly known. In Finland, during the period 1969-1985, 28 (26%) of the 106 cases of tetanus were caused by occupational accidents, 16 of which occurred in agriculture and forestry. Twenty-one of the patients were men and seven were women. The mean annual incidence of tetanus was 1 per 100,000 occupational accidents during the study period. The cases were concentrated in summer and autumn. Most of the primary injuries were minor, 61% of the injuries occurring in the hands and fingers. Forty-three percent of the patients had not been immunized against tetanus, and 46% were unaware of their state of immunization. The systematic immunization of the population against tetanus is important because the disease is often caused by slight injuries not requiring treatment by health care personnel. This need is emphasized for work in agriculture, forestry, and other branches in which contact with soil or animals occurs.


Severe farmer's lung following a workplace challenge. A severe attack of farmer's lung developed in a dairy farmer after a workplace challenge. The patient showed full recovery after corticosteroid therapy. If a workplace challenge is considered necessary in the diagnosis of farmer's lung, care should be taken to avoid unnecessarily heavy exposure to the offending antigens.


The scanning probe microscope.

The scanning probe microscope. Scanning probe microscopy has evolved into a powerful tool since its inception in 1982. The scanning probe microscope has found applications in metrology, spectroscopy, and lithography. We will review the background of the technology, discuss the different types of scanning probe microscopes including the scanning tunneling microscope and the scanning force microscope, and present many of the applications for the instrument.


Methods for the study of calcium oxalate crystallisation and their application to urolithiasis research. Many methods have been used to study calcium oxalate crystallisation. Most can be characterised by changes in supersaturation during the experiment, which may increase, remain constant or decay. Their ability to quantify various aspects of crystallisation often reflects the extent to which nucleation, growth and aggregation can be measured independently, when two or three of these processes may be occurring simultaneously. The mixed suspension, mixed product removal technique reaches a steady state supersaturation, is a good model for intrarenal crystallisation and allows both growth and nucleation rates to be measured. Using 92% urine and comparing control urines with samples from recurrent stone formers no difference in growth rates was found but the controls had higher nucleation rates (p = 0.003) and lower supersaturations (p = 0.001). In parallel crystallisers running simultaneously, heparin or hyaluronic acid addition to 92% urine was studied. Both macromolecules increased growth rates, decreased nucleation rates and increased supersaturation (p < 0.05). The steady state supersaturation achieved in this system may be an important determinant of stone forming potential. The ability to reach a lower urinary supersaturation by increased nucleation may be a crucial protective factor distinguishing non stone formers from stone formers.


A stimulus timing device for capturing fast physiologic events by quick-freezing. A timing device was designed that, in conjunction with an impact type of quick-freezing apparatus and an externally-triggerable stimulus generator, allows the application of an electrical stimulus to a muscle preparation at a selected time interval before quick-freezing and the measurement of the interval with submillisecond precision. This is needed for stopping fast physiological events in calcium release and excitation-contraction coupling and allows studying the morphological parameters (by freeze-fracture and freeze-substitution) and elemental distributions (by x-ray microanalysis) as a function of time after stimulation. The device should be adaptable for use with most equipment designed for quick-freezing electrically excitable tissue by impact on a cold solid surface.


Scanning X-ray microanalysis of microcarrier cultured endothelial cells: elemental changes during the transition to confluency and the effect of ionophore A23187. Porcine endothelial cells were grown on microcarrier beads and examined by scanning electron microscopy (SEM) at various times after initiation of culture. Total cell coverage on the bead surface varied from mean values of approximately 7% (3h) to 80% (96h). Beam penetration into the subcellular matrix presents a major problem with SEM X-ray microanalysis of microcarrier cultured cells and necessitates the use of an accelerating voltage not exceeding 10kV. At this voltage and below, X-ray contribution from elements present in the microcarrier bead has minimal effect on the determination of cell elemental levels. Washing the cells with 0.15M sucrose was the least perturbing of the rinsing techniques investigated, removing surface culture medium but not internal diffusible ions. X-ray microanalysis revealed detectable levels of Na, P, S, Cl, K and Ca in the cells, with well-marked changes from initial attachment to confluency. The level of K decreased from approximately 1.0% at 3h to 0.4% at 24h, with a corresponding decrease in the K/Na ratio. This unexpectedly low level of K was invariably observed after 24h, and is a genuine feature of established microcarrier culture. The effect of ionophore A23187 was determined at the 3h culture stage, and resulted in significant increases in the concentration of divalent cations (Mg2+, Ca2+), monovalent ions (Na+, Cl-) and a decrease in the level of K+.


Electron probe microanalysis of the otolithic membrane. A methodological and quantitative study. The effect of tissue preparation on calcium and potassium weight percent in the otoconial layer in the utricle and saccule was studied in four groups of OF1 mice with electron probe X-ray microanalysis. Glutaraldehyde and freeze-drying, glutaraldehyde and air-drying, air-drying, and cryo-fixation and freeze-drying were compared. Ca and K changed significantly in the utricle depending on the method used (P < 0.001), and K changed significantly in the saccule (P < 0.001). We chose cryo-fixation with freeze-drying for the quantitative analysis of the otolithic membrane because this method provided the highest values of Ca and K with minimum loss of Ca and K. Microcrystalline salt standards mounted on scanning electron microscopy holders were used for the quantification of Ca and K by the peak-to-local-background (P/B) ratio method. The P/B ratio in standards with reproducible results, when plotted against weight percent, gave a straight line for Ca (r = 0.99, P < 0.001) and K (r = 0.98, P < 0.001). The Ca and K weight percent in otoconia showed similar frequency distributions in the utricle and saccule.


Microwear and striae of Retzius of canines of the wild Japanese monkeys (Macaca fuscata). This is a description of microwear and striae of Retzius of canine teeth of wild-caught female Japanese monkeys (Macaca fuscata) from Oita Takasakiyama, Kyushu. Micrographs were taken of high resolution casts using a scanning electron microscope (SEM). Before the casts were made, the diet of the captive monkeys was water-softened for three or four days. This softened diet probably added little wear to the surfaces of the teeth. These animals are part of a sample used in a previous report published in this journal. Others have observed that wild Japanese monkeys eat hard foods (such as grasshoppers, cicads etc.) in the summer season. They also bite the hard bark of trees in order to obtain soft parts of buds in the winter season. The author previously reported that the wild female Japanese monkeys from Oita Takasakiyama showed many thick striations and large pits on the occlusal surfaces of the second mandibular molars, and noted that these microfeatures categorized these samples in the group of hard-object feeders as defined by Teaford. In this study canine teeth are examined. Three were heavily worn, exposing patterns related to the structure of the enamel. Two canines had prism relief on the heavily worn surfaces. Some of the relief seem to be related to the striae of Retzius. These features may be ascribed to excessive grinding (bruxism). These findings are presented as direct evidence of the effect feeding behavior has on the canine teeth of wild Japanese monkeys.


Arthropathies associated with basic calcium phosphate crystals. Basic calcium phosphate (BCP) crystals refer to a family of crystals including partially carbonate substituted hydroxyapatite, octacalcium phosphate, and tricalcium phosphate. These crystals have been found in and around joints and have been associated with several forms of arthritis and periarthritis. Identification of BCP crystals remains problematic because of the lack of a simple, reliable analytic procedure. Methods currently in use include alizarin red S staining, labelled diphosphonate binding, scanning and transmission electron microscopy with energy dispersive X-ray microanalysis, X-ray diffraction, and atomic force microscopy. Periarthropathies associated with BCP crystals include calcific tendinitis and bursitis. Intra-articular BCP crystal deposition is common in osteoarthritis, often found together with calcium pyrophosphate dihydrate crystals. Uncommon conditions in which BCP crystals are found include destructive shoulder arthropathies, acute inflammatory attacks of arthritis, and erosive arthritis. Secondary deposition of BCP crystals has been observed in chronic renal failure, in patients with "collagen vascular" diseases, following neurologic injury and after local corticosteroid injection.


Functional and morphological studies of mitochondria exposed to undecagold clusters: biologic surfaces labeling with gold clusters. This study reports morphological and functional alterations observed in respiring isolated mitochondria when they are exposed to nonpenetrating, positive electrostatically charged synthetic undecagold clusters. Modification of the undecagold clusters positive charges change or prevent the functional effects and the binding to the outside surface of the mitochondria. The mitochondrial functional alterations are dependent on the oxidative phosphorylation capacity of the isolated organelles. The results of these experiments indicate that artificial undecagold may be useful to explore the molecular mechanisms of biological energy transducers which require electric charges separation, ionic fluxes, and electric surface properties.


The use of organ cultures to study vessel wall pathobiology. Organ culture of the vessel wall is an useful in vitro method to study vascular cell biology. The intact vessel allows for the study of cell-cell and cell-substratum interactions including the structure and function of the vessel wall matrix. Long term organ cultures of porcine aorta show that neointimal formation is due primarily to cell proliferation of pre-existing intimal smooth muscle cells. Neointimal formation in these cultures is more pronounced in the presence of an endothelium that is turning over. In endothelial wound repair studies, the endothelium of the organ culture shows some important differences when compared to tissue culture studies in monolayer culture. Thus, vascular organ cultures can be successfully used to study vessel wall biology in health and disease.


Three-dimensional characterization of dense bodies in contracted and relaxed mesenteric artery smooth muscle cells. We have previously shown that dense bodies are not the static planar simple ovoidal structures they appear to be in thin sections. In this report, we present three-dimensional reconstructions from consecutive serial thin sections through shortened and non-shortened large mesenteric artery cells. Profiles of the cell surface, membrane dense bodies, and cytoplasmic dense bodies were reconstructed from consecutive thin sections and the distribution, size, shape, and spatial relationships among these components was examined. Within the cell, membrane dense bodies are numerous and occupy approximately 10% of the cell volume. Membrane dense bodies can attach to the cell surface laterally, obliquely or normally. An individual membrane dense body can be continuous over more than 2 microns of cell depth and can change shape throughout its depth. On cell shortening, many membrane dense bodies assume a crenated shape. Compared to membrane dense bodies, cytoplasmic dense bodies are smaller in all dimensions and occupy about 2% of the cell volume. In shortened cells, cytoplasmic dense bodies appear to cluster into groups. This redistribution of cytoplasmic dense bodies may be related to the reorganization of contractile units when the cell shortens.


Early effects on the morphology of mouse small intestine of single or combined modality treatment with hyperthermia and X-irradiation. This study describes the effects of hyperthermia and X-irradiation on the morphological appearance of normal, at risk tissues in the ileum of the mouse. The early morphological effects 1 day after a combined modality treatment are compared with those due to either hyperthermia or X-irradiation given alone. The response was assessed qualitatively and semiquantitatively using scanning electron microscopy and a villous scoring technique. Early post-irradiation effects on topography did not differ significantly from those observed after small intestine exteriorisation without treatment. The villous scores for the combined modality treatments reflected greater damage than would be expected from the sum of villous scores for each modality treatment on its own. This suggests that the combined modality treatment had a synergistic or enhancing effect. A 4 hour time interval between the two treatments did not seem to reduce the enhancing effect. Further studies are required to investigate the effects of fractionated combined treatment.


Morphological study of gastric lesions developing in the rat under several damaging conditions: modifications induced by pretreatment with zinc acexamate. Lesions developing in the gastric mucosa of the rat after exposure to different gastric damaging agents (100 mg/kg aspirin, and 70% or 100% ethanol) were assessed by scanning electron microscopy. The severity of the lesions was quantified according to morphological criteria. Modifications in the severity of these lesions induced by pretreatment with zinc acexamate were also analyzed. The scanning electron microscope revealed that with the exception of absolute ethanol, which caused distinctive morphological features, lesions found under the different experimental agents shared a common pattern of progression. Ultrastructural lesions on surface epithelial cells preceded further alterations of parietal cells. After the integrity of the epithelial cells was lost, detachment of the parietal cells occurred, probably, through peptic digestion of the connections between cells and their extracellular matrices. Pretreatment of animals with zinc acexamate increased the presence of mucus on the gastric surface and significantly prevented the progression of lesions towards the severest stages. Ultrastructural damage of surface epithelial cells was not influenced by this treatment, but detachment of damaged cells was clearly diminished. These data confirm the protective effect of zinc acexamate against gastric aggressions. Moreover, our studies confirm the notion that mucus secretion and maintenance of continuity on the gastric lumen by surface epithelial cells is of critical importance in preventing the gastric damage induced in these experimental models.


Appearance of venous sphincters in the pulmonary microvascular bed of normotensive and spontaneously hypertensive rats. The appearance of pulmonary venous sphincters was studied in normotensive and spontaneously hypertensive rats using scanning electron microscopy of microvascular corrosion casts and transmission electron microscopy of tissue sections. Vascular casts were prepared either after lavage with Tyrode solution or after glutaraldehyde prefixation. Pronounced pulmonary venous sphincters were more frequently identified in spontaneously hypertensive rats as compared to corresponding circular indentations in normotensive rats. Tissue sections established venous sphincters in hypertensive animals as consisting of multiple layers of smooth muscle cells in the venous walls. We did not observe any autonomic nerve terminals in close proximity to these bundles of smooth muscle cells. The effect of various casting procedures on the appearance of venous sphincters is discussed. It is concluded that glutaraldehyde prefixation is an appropriate method to demonstrate sphincter functioning, because it causes deepening of sphincter indentations. Pulmonary vascular sphincters are thought to be governed by blood-born substances, vasoactive metabolites, or by tension of oxygen and carbon dioxide. Venous sphincters may influence microvascular flow in general and probably substitute for venous valves in the pulmonary vascular bed where valves are missing.


Luminal constrictions on corrosion casts of capillaries and postcapillary venules in rat exocrine pancreas correspond to pericyte processes. The rat exocrine pancreas was studied as a model to demonstrate morphological features of different types of capillaries, using scanning electron microscopy of vascular corrosion casts and transmission electron microscopy of tissue sections. Two types of capillaries were discerned. The first type represents less undulated, slender, straight capillaries with numerous, shallow, circular or semilunar furrows on its cast's surface. In tissue sections, this type probably corresponds to non-fenestrated capillaries. The numerous grooves on its cast correspond to pericyte processes beneath the endothelial lining. The second type comprises capillaries of an undulated course and variable diameter with less numerous furrows. In addition, these casts showed circumscribed, smooth surfaced bulging areas defined by the grooves described. In tissue sections, this type probably corresponds to fenestrated capillaries, the bulging areas on its cast correspond to fenestrated regions of the endothelium. Fenestrated areas of capillary endothelium are less reinforced; pericyte processes are not present beneath these regions in tissue sections. The hypothesis that pericyte processes are responsible for surface indentations on capillary casts was supported by observations on postcapillary venules. Casts of these vascular segments showed also numerous circularly running furrows. Accordingly, the wall of postcapillary venules is provided with pericytes while smooth muscle cells are missing.


Vascular anatomy of the pig kidney glomerulus: a qualitative study of corrosion casts. Pig kidney glomerular vascular anatomy was studied by scanning electron microscopy of vascular corrosion casts. A generalized vascular architecture is presented to describe the pig kidney glomerulus based upon the observation of 3,800 vascular cast glomeruli. The relative simplicity of the pig glomerular vascular architecture has allowed the characterization of different vascular segments more completely than has been possible in other mammals. Based upon relationships to the afferent arteriole, a nomenclature and definition of primary, secondary, tertiary and anastomotic vessels is proposed for the distributing vessels comprising the glomerular tuft. The existence and formation of a large central hemispheric vessel deep within the confines of a glomerular hemisphere is micrographically documented. Micrographic evidence is presented supporting the formation of the single efferent arteriole by the merging of two central hemispheric vessels within the confines of the glomerular tuft. Failure of the merging of these two vessels may result in multiple efferent arterioles.


[Heart contusions: pathological findings and clinical course]. After blunt chest trauma, myocardial contusion is frequently suspected, but diagnostic criteria are difficult to define and commonly accepted recommendations for duration and form of patient monitoring are lacking. We therefore conducted a retrospective review of the hospital records of 50 consecutively hospitalized patients with the diagnosis of myocardial contusion after blunt chest trauma, and analyzed the pathological laboratory, ECG and echocardiography findings as well as the associated injuries and cardiac-related complications. The average injury severity score was 25 +/- 8. Initially 98% of the patients were hemodynamically stable. In 90% there were abnormal enzyme levels consistent with myocardial injury. Typically, the maximum level of CPK-MB, LDH and CPK-MB/CPK (MB-fraction) was found initially and these values declined rapidly. The MB fraction normalized within 8 hours. In 32% of the patients there were the following ECG changes consistent with myocardial contusion transient: ventricular tachycardia (12%), ST/T changes (12%), complete right bundle branch block (10%), atrial fibrillation (4%), first degree AV block (2%). The episodes of ventricular tachycardia were registered within the first 24 hours; in 5 of these 6 patients the admission ECG was normal. An echocardiography was done in 64% of the patients and in 37% showed either a pericardial effusion, regional wall motion abnormalities, a pneumopericardium or an intramyocardial hematoma in the free wall of the right ventricle. One patient died of multiorgan failure during this hospitalization. There were no sudden cardiac deaths. The diagnosis of myocardial contusion is vital in unstable patients but also very important in hemodynamically stable patients, despite its low morbidity. The minimum program we recommend for diagnosis and monitoring should include enzyme levels (CPK, CPK-MB) and ECG controls. Echocardiography may be necessary as well. If during the initial compulsory 24 hour monitoring of ECG and hemodynamics no complications occur, further monitoring is not necessary.


[Percutaneous endoscopic gastrostomy in the rehabilitation of neurological disorders]. Chronic enteric alimentation is preferred to parenteral nutritional support not only during intensive care but also during rehabilitation in severe neurologic disorders such as brain injury and high tetraplegia. As the long-term placement of nasogastric tubes has several disadvantages and undesirable side effects, we chose the nonoperative endoscopic technique for placement of a transdermal gastric feeding tube. PEG was performed in 40 patients with neurologic conditions associated with impaired swallowing or repeated aspiration problems: 20 patients with CNS trauma, 13 patients with high tetraplegia and 7 patients with severe neurologic disease of the CNS. The procedure used was that described by Gauderer and Ponsky. It was performed under local anesthesia in the majority of cases and under intravenous sedation in all cases. Technical problems practically did not occur, while minor complications were seen in 15% of the patients treated and major complications in 2.5%. Because of the high rate of peristomal wound infections despite systematic antibiotic prophylaxis, it was assumed that percutaneous infections could be secondary to contamination of the transcutaneous wound with oropharyngeal bacteria and local disinfection of the mouth with betadine has now been started before the procedure. Percutaneous endoscopic gastrostomy is a relatively safe (morbidity of less than 10%), very practical and cost-effective technique. It is well tolerated by the patients in whom swallowing mechanisms are impaired, affords advantages in regard to nursing care and should therefore belong to the standard therapeutic procedures in neurologic rehabilitation.


[Rubella epidemiology in military recruit schools]. In 1986, at the start of their training, 6877 male recruits were screened for the presence of anti-rubella IgG antibodies. 595 (9%) were seronegative. Of the latter group, 475 (80%) were retested in the week prior to discharge. During their four months of training, 113 (24%) exhibited seroconversion which proved acquisition of a rubella virus infection during the period of service. A clinical diagnosis of rubella was established in 15 (13%) of the persons with seroconversion. Catarrhal symptoms were present in half of those infected, whereas 41 (36%) did not report sick, suggesting a subclinical course of infection. Rubella is hardly a problem for the military in Switzerland. However, outbreaks such as the ones reported may have implications for the epidemiology of rubella in the general population, and hence should be taken into account in the planning of programs attempting to eliminate rubella virus infections.


[Intellectual and neurological development of 9-15-year-olds who were born as at-risk neonates]. This retrospective study deals with 296 children born between 1, Jan. 1974 and 31, Dec. 1980, who had been hospitalized as newborns at the Department of Pediatrics of the University of Berne and who had been considered at risk for abnormal psychomotor development because of well defined perinatal risk factors. Their psychomotor development had first been evaluated in the first months and years of life at the Cerebral Palsy Centre at Berne. In 1989, when the children were 9-15 years old, their neuro-intellectual development was investigated through a questionnaire sent to the families dealing with the subsequent psychosocial and scholastic course. In the CP-Centre, at a median age of 10 and mean age of 26.4 months, 247 (83.5%) of the children had been discharged with the finding of normal psychomotor development, 25 (8.4%) had been considered to show questionable findings and 24 (8.1%) to show obvious abnormal psychomotor development. On the basis of the answers to the questionnaire (median age 11 8/12, mean age 11 10/12 years; 62% return rate), 39.3% of the children had had no further problem, and 57.4% had used special support such as speech therapy or educational consulting and/or had had school problems. 3.3% showed distinct learning disabilities. More than 90% were attending a normal public school. This corresponds to the attendance in the general population. However, fewer children were in higher schools. To investigate whether the judgement in the first months and years (CP-Centre) of life corresponded to the further development (questionnaire), a subpopulation was specially evaluated in addition.(ABSTRACT TRUNCATED AT 250 WORDS)


[Hypoglycemia and multiple myeloma].

[Hypoglycemia and multiple myeloma]. We report the case of a 78-year-old patient with recurrent attacks of severe fasting and late postprandial hypoglycemia, whose plasma showed highly elevated concentrations of immunoreactive insulin evidenced by high titers of spontaneous insulin and proinsulin-binding antibodies. Insulin autoimmune syndrome was diagnosed. Further investigations revealed a multiple myeloma of the kappa-light chain type. The monoclonal insulin-binding antibodies were characterized as IgG2-subclass and were identical with the paraprotein, thereby confirming that the insulin-binding antibodies were in fact produced by the myeloma. Together with initial symptomatic treatment, plasmapheresis was performed repeatedly to reduce the antibody pool. Subsequently octreotide therapy proved successful. The underlying myeloma was treated by chemotherapy.


[Neuroradiology of the spinal cord].

[Neuroradiology of the spinal cord]. In recent years MR has assumed a central and key role in neuroradiological evaluation of the spinal cord. Because of its noninvasiveness and high sensitivity in the detection of intramedullary lesions, it represents the method of choice today for the work-up of acute, chronic and traumatic myelopathies. The main limiting factor of MR is its rather low specificity. For this reason the clinical history as well as the neurological and laboratory findings continue to be of major importance in arriving at a definite diagnosis. The method is contraindicated in patients with pacemakers or other intracorporeal paramagnetic devices. It is relatively contraindicated in claustrophobic patients. In these cases MR should be replaced by myelography or CT-myelography. For the diagnosis of vascular diseases of the spinal cord, specifically vascular malformations and hypervascular tumors (e.g. hemangioblastoma), selective spinal angiography represents an essential adjunct to MR. Selective angiography can also be used therapeutically to treat preoperatively or definitely vascular malformations (i.e. interventional neuroradiology).


[Imaging of the spine].

[Imaging of the spine]. Modern imaging techniques allow early and precise diagnosis of spinal diseases. Their sensitivity and specificity are variable, but in general they are more complementary than competitive. After emphasizing the different patterns which characterize the late evolution of diagnostic imaging, the author reviews the indications and limits of plain films, bone scintigraphy, computed tomography, and in particular of magnetic resonance, in trauma, degenerative lesions, inflammations, infections and tumors of the spine.


[Evaluation and documentation of tomographic images and further data using the Apple-Macintosh PC]. Use of the personal microcomputer for the analysis of clinical cardial PET studies acquired at the Paul Scherrer Institute in Villigen, Switzerland. At present this is the only PET facility in Switzerland. As the local computers were not usually available for image analysis, it was necessary to find a convenient way to visualize and analyze the PET images in our department in the Cantonal Hospital, Aarau (distance to Villigen some 30 km). The personal microcomputer is, as other authors have already shown, in fact capable of handling the acquired images (128 by 128 pixels) easily. We use a Macintosh IIcx (16 MHz Motorola 68030 CPU) as image analysis workstation. In spring 1990 we implemented a software which could read the original Siemens matrix file directly into the Macintosh PC. As the handling of this software was somewhat clumsy, we now use a very powerful software ("Explorer", UCLA), which is specially designed for PET analysis. Analysis of PET data on the personal computer saves both time and money as we are able to use a standard PC periphery, which is less expensive than specially designed medical units.


[Sphincter-preserving radiotherapy of anal carcinoma]. During the last decade radiotherapy, in combination with chemotherapy, has become the treatment of choice in cure of anal carcinoma with preservation of anal function, and has replaced abdominoperineal resection (APR). From 1979-1990 54 patients with anal carcinoma were treated by radiotherapy. 24 patients received radiotherapy after APR (12 adjuvant, 12 after recurrence). 11 received palliative radiotherapy without prior APR. 19 patients were treated curatively, 17 of whom received a combination of external irradiation followed by interstitial iridium implantation in a split course regimen. 11 of the 19 patients received short simultaneous chemotherapy (mitomycin C and 5-fluorouracil). All 19 patients had a complete remission. 18/19 patients had no local recurrence after mean 14 months' follow-up. 2 patients developed regional recurrence. 3 patients died of other causes. Colostomy was necessary in 5/19 patients with anal necrosis which was dose-related. The maximum tolerated dose was 71.4 Gy. Our results support the recommendation in the literature of primary, curative, radiotherapy and chemotherapy of anal carcinoma with preservation of the anal sphincter.


[Current aspects in the pathogenesis and therapy of glomerulonephritis: significance of glomerular metalloproteinases]. The extracellular matrix, comprising the glomerular basement membrane and the mesangial matrix, plays a crucial role in glomerular structure and function. The glomerular extracellular matrix is composed of collagens, proteoglycans and glycoproteins. The distorted balance between synthesis and degradation of extracellular matrix proteins is a hallmark of many forms of glomerulonephritis, such as glomerulosclerosis. The degradation of the matrix occurs through the action of a group of extracellularly active metalloproteinases. Within the glomerulus these enzymes are synthesized by the epithelial and the mesangial cells. The molecular structure of the mesangial metalloproteinases, including their in vitro regulation, was analyzed and the in vivo synthesis of these proteinases was documented for cases of idiopathic rapid progressive glomerulonephritis and anti-Thy 1.1 nephritis. The therapeutic change in the activity and expression of the glomerular metalloproteinases, resulting in the restoration of physiologic matrix metabolic balance, opens up a new perspective for the therapy of glomerular inflammatory processes.


[Immediate and long-term results of carotid endarterectomy: the Zurich experience]. Extracardial carotid artery disease is a frequent cause of transient ischemic attack and of cerebral infarction. The records of 485 patients who underwent carotid endarterectomy between 1978 and 1991 were reviewed, with special attention to both cardiac and neurological complications. 432 patients had symptomatic carotid disease whereas 53 were asymptomatic but presented with significant carotid stenosis or a large ulceration at doppler-duplex examination and/or angiography. These examinations showed the following lesions in symptomatic patients: unilateral stenosis > 75% (331; 68.5%), ulceration (41; 8.5%), bilateral stenosis (61; 12.5%) and unilateral stenosis with contralateral occlusion (51; 10.5%). Intraluminal shunt was used in nearly all patients whereas special management of cerebral metabolism (intraoperative electroencephalogram, somatosensory evoked potentials) were used in high-risk patients only. Overall early mortality was 1.8%. Three patients died from the sequelae of a neurologic injury, whereas six patients died from myocardial infarction or intractable arrhythmia. Mortality decreased from 2.4% between 1978 and 1984 to 0.8% between 1985 and 1991. At 6 and 8 years, actuarial survival rates of 88.1% and 76.1% and stroke-free survival rates of 86% and 81.5% were observed. Late mortality was essentially due to ischemic cardiac complications (38.5% of the actuarial late mortality at 8 years). Review of the literature shows that carotid endarterectomy is the treatment of choice for symptomatic high-grade extracranial carotid stenosis in patients who are not high-risk candidates.(ABSTRACT TRUNCATED AT 250 WORDS)


[Reliability of bronchial tumor typing base on fibroscopically obtained biopsies]. This study is based on the bronchial tumors biopsied and later examined between 1971 and 1986 at the Institute of Pathology, Lausanne. In each case the diagnosis based on the initial biopsy material is compared with the final surgical or autopsy diagnosis (Reference: Histological typing of lung tumours, second edition, WHO, 1981, 2). The series studied is constituted by 163 cases: 144 men (88.3%) and 19 women (11.7%). In 136 cases (83.4%), the biopsy diagnoses are identical to the diagnoses based upon surgical or autopsy material; in 27 cases (16.6%) these diagnoses differ. The positive predictive value of bronchial biopsy appears to be excellent (100%) for small cell and epidermoid carcinoma (CA). It is satisfactory for adenocarcinoma (85.7%) but insufficient for large cell CA (42.3%) and the tumors grouped under "others" (50%). The diagnosis of large cell CA, in situ CA, papillary tumor, undifferentiated CA, or carcinomatous lymphangitis should be considered with caution and in some cases it is advisable to repeat the biopsy. The discrepancies between the initial and final diagnoses can, in all cases, be attributed either to the biopsy specimen being too small and therefore nonrepresentative or, less frequently, to crushing and necrosis of the tissues.


[Primary prevention of osteopenia].

[Primary prevention of osteopenia]. In industrialized countries the clinical and socioeconomic importance of osteoporosis has been well recognized in recent years. Various treatments have been introduced for secondary prevention in established osteoporosis. There is, however, a deficit in the primary prevention of osteopenia. In every age group physical exercise stimulates mineralization of the bone. With regular training adolescents can achieve a higher peak bone mass. In old age the physiologic decrease of bone mass can be retarded by physical exercise. A diet rich in calcium has positive effects on mineralization of the bone. Estrogens have proved efficacious in the prevention of osteoporosis in postmenopausal women. Abstinence from nicotine and alcohol contributes to the prevention of osteopenia.


[The effect of 2 finishing methods on the micromorphology of the proximal box margin. An in-vivo study]. Minipreparations of class II cavities often are not employed in daily practice mainly because adequate instruments for finishing the axial box margin and the proximo-cervical curvature were not available. The purpose of this in vivo study was to assess the morphology of the proximal box margin after finishing with two different methods. 81 class II minicavities for amalgam restorations were prepared by 4 dental practitioners. One method for finishing the axial box margin and the proximo-cervical curved border was the use of a modified EVA-System with the total amplitude reduced to 0.4 mm and a highly flexible file (Cavishape, grain 25 microns). The other method was the use of an axial margin trimmer. The micromorphology of the two methods was investigated by means of scanning electron microscopy and a score system as described earlier (Lussi et al. 1987). The margins of the axial box as well as of the proximo-cervical curvature were significantly better finished with the EVA-System and the highly flexible file compared to the axial margin trimmer (p < 0.001). The finishing time for the box margin was not significantly different using the EVA instrument or the axial margin trimmer. These findings confirm other in vitro investigations. This in vivo study shows that the modified EVA instrument with the highly flexible file (Cavishape, grain 25 microns) is clearly superior to the axial margin trimmer in finishing the box margin. This device allowed a significant better finishing of the axial box margin and the proximo-cervical curvature of minicavities in daily practice.


[The preparation of enamel margin beveling in proximal cavities]. Minicavities for posterior composite resin restorations were prepared in 24 caries-free teeth. The aim of this in vitro study was to evaluate the micromorphology of the proximal cavosurface bevel. The cavosurface bevel has been employed for many years as an accepted modification for composite restorations in permanent anterior teeth. The bevel provides more exposed enamel rod ends available for bonding. Using the acid-etch technique the resin-enamel bond is stronger with etched transverse sections of enamel prisms than with longitudinal sections. Enamel in the proximal and gingival wall of class II cavity preparations for restoration with composite should be beveled because prism direction is at right angles to the surface. The aim of this study was therefore to compare two methods for beveling the box margins of small proximal cavity preparations. One method for the preparation of the proximal bevel was the use of a modified EVA-System with the total amplitude reduced to 0.4 mm, the fixation of the file position and a new developed file (Bevelshape, grain 40 microns). The form of this file was modified in order to produce a short cavosurface bevel of the gingival and proximal wall without danger of damaging the adjacent tooth. The other method was the use of an axial margin trimmer. The micromorphology of the two methods was investigated by means of scanning electron microscopy and a score system as described earlier (Lussi et al. 1987). Statistical analysis revealed significant differences between the two groups. As compared to the axial margin trimmer the new device allowed a significant better finishing of the proximal bevel (p < or = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


[The marginal sealing of composite inlays with different cavity liners]. In this in-vitro study we investigated the sealing properties of composite inlays (EOS system) dependent on 8 different base materials. Using a dye-penetration test, the sealing was determined after mechanical and thermal cycling. A partially massive dye-penetration was detected in most cases when one of the following materials was used: a calciumsalicylate cement (Dycal), a combination of calciumsalicylate cement and a resin (Basic), a calcium hydroxide filled resin (Prisma VLC-Dycal), or a zinc phosphate cement (Harvard Cement). In contrast to this, we discovered a complete or almost complete sealing in most cases after application of chemically-cured glass ionomer cements (Ketac-Bond, Ketac-Bond Aplicap, Base-Line) or a light-cured glass ionomer cement (XR-Ionomer) as base materials. From these results it can be concluded that the choice of base materials has an influence on the marginal sealing of composite inlays after thermal and mechanical cycling. However, it is not possible to make a definitive statement on the suitability of these base materials under clinical conditions, because the results of dye-penetration tests have only limited clinical validity.


[The surface roughness of orthodontic wires--a laser optical and profilometric study]. The surface roughness of orthodontic wires is an essential factor that determines the effectiveness of arch guided tooth movement. Using the nondestructive technique of laser specular reflectance, the surface roughness of 11 nickel titanium orthodontic wires and a standard steel as well as a beta-titanium wire was measured. The results were compared with the results from surface profilometry. The smoothest wire, standard steel Hi-T, has an optical roughness of 0.10 microns, while the roughness from profilometry reached a value of 0.06 microns. The titanium molybdenum wire has an optical as well as a profilometric roughness of about 0.20 microns, while the roughness of the NiTi wires ranges from 0.10 microns to 1.30 microns. As the surface roughness not only influences the effectiveness of sliding mechanics, but also the corrosion behaviour and aesthetics, the manufacturers of orthodontic wires are asked to improve the surface quality of their products.


[Signal transduction in normal and neoplastic cells]. This review describes molecular mechanisms involved in intracellular signal transmission. Special focus is given on calcium and calcium binding proteins as signaling intermediates. These strictly controlled biochemical reactions prevent uncoordinated proliferation which may lead to tumor development. Generally, signal transduction pathways are very similar among higher eukaryotes. Mutations in genes responsible for signal transmission and growth control (protooncogenes and tumor suppressor genes) are often found in tumors or cancer cell lines.


[Control of gastrointestinal strongylids in first year calves: use of Paratect Flex bolus at late pasture turnout]. The efficacy of the Paratect Flex-Bolus for the control of parasitic gastroenteritis in calves was evaluated in a field experiment in the Swiss midland region. The bolus was administered to 9 first year grazing calves at 4 to 5 months of age before turnout on June 26 while 9 calves remained as untreated controls. Both groups were rotated between 8 paddocks that had been pregrazed by older cattle in spring. For a period of 12 weeks the faecal egg output of the treated calves was reduced significantly (p < 0.05) compared to the controls, whereas no significant differences were observed in the mean serum pepsinogen values of both groups. At the end of the experiment (November 14) the bolus-treated calves showed a 4 kg weight gain advantage over the controls which was not significant. The mild infection levels in both groups were probably due to the low pasture contamination with infective larvae throughout the season which most likely resulted from the late turnout of the calves. An outbreak of dictyocaulosis was observed in both groups in October and confirmed that the Paratect Flex-Bolus provides insufficient protection against this infection.


[Suspicion of visna in a sheep from Graubünden Canton]. A lentivirus belonging to the group of retroviridae causes a chronic progressive interstitial pneumopathy (maedi) or a demyelinating encephalo-myelitis (visna) in sheep and goats. Pulmonary lesions of maedi as well as sero-positive, clinically healthy animals can be observed in Switzerland; visna, which even in countries with endemic infection does not occur frequently, is extremely rare. The head and cervical spine of an ewe with severe nervous troubles suspected of scrapie were submitted for postmortem examination. We found a demyelinating myelitis resembling visna. Immunocytochemical staining (PAP) to demonstrate the presence of the virus in paraffin sections was negative, but several animals of the flock proved to be seropositive for maedi/visna virus, which supports the histological diagnosis. Although there is no risk of an epidemic outbreak of maedi/visna in Switzerland, modes of transmission, eradication programmes and prophylactic measures successfully employed in countries with endemic maedi/visna are discussed.


[Intra-individual variation of cerebral blood flow velocity in sleeping and awake children]. A considerable intraindividual variability of blood flow velocities in the middle and posterior cerebral artery was found in 74 children by continuous transcranial Doppler recording during EEG registration. The coefficient of variation of the mean flow velocities in the posterior cerebral artery was higher than in the middle cerebral artery, and higher in restless children than in calm children. During hyperventilation the mean flow velocities decreased to about 50 per cent of the baseline values. They increased to 130-140 per cent of the baseline values after hyperventilation. Repeated variations of the velocities of more than 30 per cent of the baseline values were observed during non-REM sleep in the majority of the children. They may be caused by a lower damping of the cerebral autoregulatory response. The intraindividual variability of cerebral blood flow velocities in children has to be kept in mind in pathological conditions and during Doppler monitoring.


[Transcranial Doppler sonography with evaluation of CO2 reactivity in craniocerebral trauma]. 17 patients with severe head injury were examined by transcranial Doppler sonography. Resting values and CO2 reactivity were determined. The resting measurements had no prognostic value. There was no significant side difference in patients with unilateral intracranial lesions. CO2 reactivity was 2.8 +/- 2.3%/mmHg pCO2 in patients with good outcome, whereas in patients with bad outcome CO2 reactivity was 0.6 +/- 5.1%/mmHg pCO2. However, in the acute situation after the trauma there was no difference between the two. In patients with a unilateral lesion we found a significantly lower CO2 reactivity on the side of the lesion of 1.8 +/- 0.4%/mmHg pCO2, on the non-affected side CO2 reactivity was 4.5 +/- 2.1%/mmHg pCO2. The conclusion is that the CO2 reactivity yields information on the actual haemodynamic situation in brain-injured patients. Repeated measurements are necessary to improve the prognostic value of CO2 reactivity, because this parameter may improve during treatment.


[Various ultrasound methods for studying the vertebral artery--a comparative evaluation]. In a prospective study 451 patients were examined with extracranial continuous-wave (CW) Doppler sonography, transcranial Doppler sonography and color coded duplex sonography in order to evaluate the diagnostic accuracy of the three methods for vertebral artery pathology (hypoplasia, proximal and distal stenosis and occlusion). Color duplex sonography was used as the reference method. CW-Doppler sonography (mastoidal slope) had a sensitivity of 100% and a specificity of 27% for the detection of pathological changes in vertebral arteries (VA). For suboccipital transcranial Doppler sonography these values were 38% and 58%. Extracranial Doppler sonography and transcranial Doppler sonography are often unsuitable for differentiating between proximal stenosis and hypoplasia of VA. Transcranial Doppler sonography of the terminal segments of VA resulted in normal flow parameters in 27% of cases with proximal stenosis and in 50% in cases of proximal occlusion. Flow was normal in these particular cases owing to a more distal collateralisation of the VA. The terms "hypoplasia" and "asymmetric" of VA are discussed.


[Catheter-induced femoral artery lesions: diagnosis with B-mode ultrasound, Doppler ultrasound and color Doppler ultrasound]. A total of 44 patients were evaluated to compare the value of B-mode sonography, Doppler sonography and colour coded Doppler sonography. All patients were studied because of suspected lesions of the femoral arteries following diagnostic and/or therapeutic cardiac catheterisation. B-mode sonography was unable to reliably differentiate between haematoma and pseudo-aneurysms, a.v.-fistula or combined lesions. Colour coded Doppler sonography can better demonstrate haematoma and thrombi in pseudo-aneurysms. The neck of a pseudoaneurysm can be exactly depicted by colour coded Doppler sonography. A.v.-fistula is shown by colour coded Doppler sonography based on typical colour coding and the Doppler spectrum. Combined lesions of pseudo-aneurysm and a.v.-fistula cannot reliably be detected by colour coded Doppler sonography, duplex sonography and B-mode sonography.


Atlantoaxial instability in Down's syndrome: a case report and review. Down's syndrome is the most common autosomal chromosomal abnormality in humans and is associated with a number of well known clinical findings. Atlantoaxial instability is a less recognized, yet potentially significant, manifestation of Down's that has gained importance because of the widespread participation of Down's syndrome individuals in athletic events. Early recognition and appropriate management of patients with atlantoaxial instability can significantly reduce the morbidity and mortality associated with this condition and guide patients and their parents toward continued safe participation in athletics.


Tuberculous peritonitis: a case report and literature review. We present a case of tuberculous peritonitis in the setting of alcoholic cirrhosis with ascites. A young American Indian male with alcoholic cirrhosis and ascites presented with low grade fever and weight loss. A diagnosis of tuberculous peritonitis was made by laparoscopic guided peritoneal biopsy. He was treated successfully with isoniazid and ethambutol for 24 months. The diagnosis of tuberculous peritonitis should be entertained in high risk populations such as American Indians, Asians, alcoholics, chronic ambulatory peritoneal dialysis patients and AIDS patients in the appropriate clinical setting. Definitive diagnosis can usually be made by laparoscopic guided peritoneal biopsy.


A condom sense approach to AIDS prevention: a historical perspective. Condoms have come a long way since their use in ancient Egypt three millennia ago. Their benefit is well established for the prevention of both contraception and STDs. Although AIDS has revitalized the condom, we must remember that condoms do not prevent the spread of HIV infection, people do. Everyone must take personal responsibility to avoid high risk behavior (e.g.; IV drug use, promiscuous sex, casual sex, etc). If one does engage in high risk sexual behavior, he/she should at least use condom sense.


Toxic metal pollution in Africa.

Toxic metal pollution in Africa. The available information suggests that the concentrations of toxic metals in many ecosystems of Africa are reaching unprecedented levels. Because of the heavy load of contaminated dusts in the air of the overcrowded cities, the ambient concentrations of toxic metals are now among the highest being reported anywhere. Lead pollution from the increasing number of automobiles and cottage industries represents a major health hazard, and it is estimated that 15-30% of the infants in some urban areas may already be suffering from lead poisoning. The cultural and lifestyle determinants of lead exposure and the greater susceptibility of African populations to environmental metal poisoning are highlighted. The suggestion is made that the environmental health criteria for toxic metals in the developed countries may not provide adequate protection for many African communities.


The transport and fluvial redistribution of Chernobyl-derived radiocaeisum within the River Wye basin, UK. Relatively little attention has been given to the long term prospect of fluvial transport processes redistributing Chernobyl-derived radiocaesium within the UK. Work undertaken within the Wye basin, central Wales, demonstrates a complex distribution of fallout at the catchment scale, with the bulk of the deposition concentrated in a narrow north-south band, situated in the west central areas of the basin, which contained in excess of 1500 Bq m(-2) of (134)Cs. Fluvial transport and redistribution of this material was demonstrated by river sampling during the winter of 1988/89, when the radiocaesium content of suspended sediment transported by the River Wye (approximately 30-50 mBq g(-1) of (137)Cs) remained 3-5 times higher than pre-Chernobyl levels. Floodplain reaches displayed variable levels of secondary contamination, dependent upon the upstream supply of radiocaesium and local morphological controls. Accordingly, the highest (134)Cs inventories within the basin (> 6000 Bq m(-2)) were associated with rapidly accreting floodplain sites. A number of these sites experienced only limited amounts of direct atmospheric fallout. The importance of fluvial redistribution as a secondary contamination mechanism is thus highlighted.


Contamination of plants by resuspension: a review, with critique of measurement methods. Resuspension of contaminated soil particles can be an important process that prolongs the availability of contaminants within the environment. Inhalation and inadvertent ingestion of resuspended soil particles may be important pathways to human exposure. Our understanding of the processes and mechanisms of resuspension onto plant surfaces are currently inadequate for accurate predictions. Part of this is due to the use of measurement techniques designed for inhalation studies that are not efficient for gaining understanding about phenomena occurring at the plant surface. I discuss the shortcomings of such techniques, review the data from a technique that currently has the most merit (mass loading), and suggest new techniques, as well as specific needs for future research. The paper's focus is on the contamination of plant surfaces by resuspended soil particles, not the inhalation of such particles.


Solar UV irradiance and some biological consequences: Bombay, India. Measurements of solar UV radiation (UVR) at Bombay, India, lattitude 18.5 North and longitude 72.5 East were recorded using Eppley UV radiometer for a 2-year period. The UV irradiance is calculated and presented. The annual and diurual trends in the quantitation of UVR are examined. The consequences of solar UVR and its projected increase are discussed with special reference to its biological effects and results of UVR on experimental animal systems vis a vis and epidemiological data in the Indian context.


The transport of airborne trace elements copper, lead, cadmium, zinc and manganese from a city into rural areas. The fluxes of the elements lead, zinc, copper, cadmium and manganese have been measured in the insoluble component of bulk deposition derived from Christchurch, New Zealand. Lead, zinc, copper and cadmium fluxes follow approximately exponential decay curves away from the city whereas manganese deposition showed little spatial variation. A similar composite source originating in the city is indicated for the lead zinc, copper and cadmium and a different major source occurs for manganese. In the city and nearby rural areas soil is not a major source of atmospheric lead, zinc, copper and cadmium, whereas at remote sites atmospheric levels of these elements are mostly soil derived. Seasonal variations in the bulk deposition are large within the city, and at upwind rural sites. The variations are controlled by meteorological conditions, in particular wind speed and the height of the mixing layer. Compared with overseas studies, the proportion of the metals occurring in the soluble fraction of the bulk deposition is low. This may be due to the relatively dry climate of the area.


Occurrence of butyltin species in sewage and sludge in Canada. Samples of sewage treatment influent, effluent and sludges collected monthly from five Canadian cities over the period from July 1990 to January 1991 were analysed for butyltin and octyltin species. Monobutyltin was found in all influent samples, but dibutyltin and tributyltin were found only infrequently, and octyltin species were not found at all. In the case of monobutyltin, there was significant reduction in its concentration by degradation and adsorption to sludge during passage through the sewage treatment plant. The average reduction was 40%. The monobutyltin found in the effluent likely came from its use as a poly (vinyl chloride) stabilizer, and from the degradation of tributyltin, which is used as a slimicide. No butyltin or octyltin species was found in five landfill leachate samples in southern Ontario during the same period.


Radon concentrations inside castles and other ancient buildings. Sixty-two measurements of Rn-222 concentrations were made in 24 castles and 13 ancient buildings in 30 different places situated in the provinces of Parma and Reggio Emilia (Northern Italy). The method used was that of activated carbon canisters which were placed in selected settings for at least 48 h in the period starting from December 1990 to May 1991. It was possible to determine the amount of radon in each canister via its daughters gamma emitters counted by NaI(T1) and Ge(I) detectors. The mean radon concentrations were 72 Bq m-3 (arithmetic mean) and 49 Bq m-3 (geometric mean), a good deal higher than the values obtained from measurements carried out in modern dwellings in the same area; 30 Bq m-3 (arithmetic mean) and 19 Bq m-3 (geometric mean).


In vivo detection of genotoxicity in waste water from a wheat and rye straw paper pulp factory. The genotoxicity of waste water from a wheat and rye straw paper pulp mill was investigated by in vivo genotoxicity tests using micronuclei and sister chromatid exchange as endpoints. Micronuclei were studied in mussels (Mytilus edulis) and sister chromatid exchange in fish (Nothobranchius rachowi). The paper mill uses chlorine dioxide for bleaching, and the bleaching effluent as well as the combined effluent, i.e. the mixture of all waste water streams, were both tested. Both effluents induced micronuclei and sister chromatid exchanges, although the presence of toxic substances could mask the expression of genotoxicity in some cases for both test systems. The study revealed that genotoxins are produced in the chlorine dioxide bleaching process as well as in the pulping process, indicating also genotoxic activity of non-chlorinated compounds. In contrast to previous studies in which mutagenicity was determined with bacterial assays, genotoxins were only associated with chlorinated organics from bleaching with chlorine and failed in detecting genotoxins in chlorine dioxide bleaching effluents. Aquatic in vivo genotoxicity tests are sensitive and efficient systems and seem to be a promising tool in effluent testing.


ELISA test, a new method to detect and quantify isoproturon in soil. An indirect competitive Enzyme-Linked ImmunoSorbent Assay (ELISA) has been developed to quantify isoproturon (a commonly used phenylurea herbicide) in soil samples. To produce the specific antibodies needed for detection of isoproturon, an isopropylanilin analogue was covalently linked to a proteic carrier and the resulting conjugate used as immunogen. Hybridomas were obtained from spleen cells of mice immunized with this conjugate. One specific monoclonal antibody (MAb) was selected and used to the ELISA allowing the detection of small amounts of herbicide (20-250 micrograms l-1). Cross-reactivities with other current phenylureas appear to be insignificant. Samples of six soils were mixed with several quantities of herbicide (to reach final concentrations ranging between 0.15 and 1 microgram g-1) and extracted either with methanol to determine the total residue or with a solution of CaCl2, to establish the herbicide available from the soil solution. The extracts were analyzed simultaneously by gas chromatography and ELISA in these conditions, correlation coefficients between both methods were never lower than 93.5%. Organic matter and ionic strength appeared to be the most important parameters interfering the ELISA test. To avoid these drawbacks, standard curves were established for the ELISA by spiking isoproturonless soils extracts. In these conditions, correlations between both methods were considered as sufficient. ELISA of untreated samples were carried out to verify the isoproturon availability curves established previously.


Biological and chemical interactions of pesticides with soil organic matter. There is little doubt that organic matter plays a major role in the binding of pesticides in soil, and that this phenomenon is usually the most important cause for interaction of pesticides in the soil environment. Fulvic or humic acids are the chemicals most commonly involved in the binding interactions. Binding can occur with the original pesticide or a transformation product, the reaction being caused by abiotic agents or biotic agents (microbial or plant enzymes). The reactions or processes involved appear to be the same as those responsible for the formation of humic substances, i.e. for the humification process. Binding of pesticides to organic matter can occur by sorption (Van der Waal's forces, hydrogen bonding, hydrophobic bonding), electrostatic interactions (charge transfer, ion exchange or ligand exchange), covalent bonding or combinations of these reactions. Our investigation focused primarily on the binding of substituted phenols and aromatic amines to humus monomers and humic substances. In model reactions, we demonstrated the formation of covalent linkages between pesticides and humus constituents and fulvic or humic acids in the presence of phenol oxidases or clay minerals. With chlorinated phenols and carboxylic acids, it was possible to isolate and identify cross-coupling products and to elucidate the site and type of binding. The binding of chlorinated phenols to humic substances was determined by using 14C-labelled chemicals and by measuring the uptake of radioactivity by the humic material. These experiments provide a base for explaining the formation of bound residues in certain cases and for assuming the toxic potential of the immobilized pollutants.


Molinate decontamination processes in effluent water from rice fields. The performance of aeration, photodecomposition and biological degradation processes as methods to reduce molinate contamination levels in effluent water from rice fields was studied. Aeration produced a molinate dissipation of 84%, as against 22% without aeration. Application of UV-light to clean water solutions achieved a molinate photodecomposition of 96% in 24 h. Maximal degradation obtained in algal cultures was 55% in 20 days and 78% in 40 days. In micro-organism cultures, kept in darkness and with a continuous flow of aqueous solution of molinate and inorganic salts, a degradation of 97% was achieved.


Degradation of aliphatic halogen-substituted pesticides by dehalogenase isolated from Pseudomonas alcaligenes. Identification and properties of the enzyme. Some characteristics of a 2,2-dichloropropionate dehalogenase induced in a bacterial strain capable of degrading high concentrations of the herbicide dalapon were studied. Polyacrilamide gel electrophoresis of the crude cell free extracts identified only one type of dehalogenase. The single enzymatic protein showed activity against a variety of chlorinated aliphatic acids but differed in their activity levels. Thus activity in mumol substrate converted (mg protein)-1 min-1 was 2-monochloropropionate 0.65, 2,2-dichloropropionate 0.56, 2-monochloroacetate 1.70 and 2,2-dichloroacetate 1.00. In the crude extracts, the enzyme activity against 2,2-dichloropropionate was optimal at a broad pH range with a mid-point at pH 9.5 and apparent Km values were within the range 0.23-0.73 mM.


Gas chromatographic determination of some modern pesticides in fruits. A method was developed for determination for residual amounts of some modern insecticides, acaricides and fungicides in fruits. The pesticides were extracted with methanol and partitioned into chloroform. The extract was purified by column chromatography on sodium sulphate/Florisil/Celite/charcoal. Analysis by gas liquid chromatography with 63Ni electron capture detection was completed successively on a column (150 cm x 4 mm) with 3% SE-30 and a column (150 cm x 2 mm with 3% OV-17 liquid phase. Recoveries of 17 pesticides from fortified samples of apples ranged from 83.3% to 98.4% for a level of 0.1 mg/kg.


Relationship between the biodegradative capability of soil micromycetes for pentachlorophenol and for pentachloronitrobenzene. A collection of 1056 strains in our laboratory were incubated with various xenobiotics among which were two potent fungicides: pentachlorophenol (PCP) and pentachloronitrobenzene (PCNB). The production of extracellular phenoloxidases were examined, using a series of ten different reagents. On the whole, PCNB is less accessible to fungal degradation than PCP. Although no correlation was found between the biodegradative capability of individual fungal strains for PCP or for PCNB, when taxonomic groups were considered as a whole, the same activity profiles were found. Zygomycetes were the most efficient; yeasts the least efficient towards both substrates. A more detailed study of the metabolism of both substrates on selected strains is in progress.