Heavy metal contamination of settling particles in a retention pond along the A-71 motorway in Sologne, France

A retention pond is a part of a drainage system designed to control water flow during rainstorms and to trap contaminated solid particles washed off by runoff water from a motorway. A series of studies have been carried out concerning the physico-chemical characteristics of the particles which settle down in such a pond in order to evaluate the effectiveness of the pond as a trap for heavy metals such as Pb, Zn and Cd. The highly contaminated roadside soil and the uncontaminated background soil were also studied for comparison. The settling particles had heavy metal concentrations 2-8 times higher than the background Sologne soil, depending on the metals. Heavy metal concentrations in the roadside soil were 7-26 times higher than those in the former. Sequential extractions, using the procedure of Tessier et al. (1979) illustrate that the highly contaminated roadside soil consisted mainly of the readily soluble fractions for all three heavy metals, with a limited proportion of residual metals. In the settling particles, the proportion of the latter is significantly increased, up to one-third of the total. The high concentration differences between the roadside soil and the settling particles indicates that most of the heavy metals are lost to the surroundings even before reaching the retention pond. Cadmium exhibited a specific behavior in that the most soluble fraction (exchangeable), which is negligible for Pb and Zn, occupied as much as one-fourth of the total in the roadside soil. Based on the 'enrichment factor' normalized to Fe introduced by Helz in 1976, the degree of contamination by heavy metals for the roadside soil and the settling particles was evaluated. The level of contamination was very severe in the roadside soil, while it was not so great in the settling particles. Suggestions are made to improve their removal efficiency.

Nucleotide sequences and biologic properties of toxic shock syndrome toxin 1 from ovine- and bovine-associated Staphylococcus aureus

Toxic shock syndrome toxin (TSST) 1 was purified from ovine (TSST-ovine) and bovine (TSST-bovine) mastitis-associated Staphylococcus aureus. These toxins were previously reported to have molecular weights identical to that of human TSST-1. However, TSST-ovine was reported as having an isoelectric point (pI) of 8.5, whereas TSST-bovine has the same pI (7.2) as TSST-1. Nucleotide sequence analysis revealed that TSST-bovine was identical to TSST-1 and that TSST-ovine had 14 nucleotide differences that changed 9 amino acid residues. Only 1 nucleotide difference, at position 514, was predicted to cause an amino acid charge difference, as glutamic acid at position 132 of TSST-1 was changed to lysine in TSST-ovine. Like TSST-1, TSST-ovine was mitogenic, but unlike TSST-1, it was not pyrogenic, was unable to enhance endotoxic shock, and was unable to induce TSS in a rabbit model. Also, TSST-ovine was less reactive to certain monoclonal antibodies raised against TSST-1.

Effects of staphylococcal toxic shock syndrome toxin 1 on aortic endothelial cells

In staphylococcal toxic shock syndrome, hypotension and shock due to capillary leak may rapidly lead to death of the host. To investigate its pathogenesis, the cytotoxic effects of toxic shock syndrome toxin 1 (TSST-1) on porcine aortic endothelial cells (PAEC) were examined in vitro. TSST-1 killed PAEC (as measured by 51Cr release) in a dose- and time-dependent fashion and was blocked by anti-TSST-1 antibodies. Receptor-mediated endocytosis may be critical for the cytotoxic effects of TSST-1, as killing was inhibited by cold (4 degrees C) and by addition of chloroquine and methylamine. Furthermore, calcium and oxygen appeared necessary for TSST-1 effects on PAEC. Membrane receptor binding studies indicated PAEC bind TSST-1 with high affinity (Kd = 5.7 x 10(-7) M) and had 2.2 x 10(4) receptors/cell. Last, as measured by 125I-labeled albumin flux in a transendothelial permeability model, TSST-1 enhanced the permeability of PAEC monolayers in a dose- and time-dependent manner.

Intravenous leiomyomatosis with intracardiac extension: an unusual cause of cardiac syncope

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Atypical hepatic vein leiomyoma extending into the right atrium: an unusual cause of the Budd-Chiari syndrome

A 14-year-old male presented with a one week history of weakness, lightheadedness and vomiting. Bilateral pleural effusions were evident on chest radiography; electrocardiogram revealed decreased voltages. Echocardiogram, abdominal ultrasound and magnetic resonance imaging revealed a mass in an hepatic vein and the inferior vena cava extending up to and filling the right atrium. Under deep hypothermia and extracorporeal circulation the mass was removed en bloc. It originated from the hepatic vein. Pathology revealed a smooth muscle tumour intermediate between benign and malignant (atypical leiomyoma). This is the first reported pediatric primary leiomyoma of the hepatic vein. It caused the Budd-Chiari syndrome, a rare pediatric entity.

Two-dimensional and pulsed Doppler echocardiographic diagnosis of an acquired aortic right ventricular fistula

A patient with an asymptomatic aortic right ventricular fistula acquired after aortic valve and mitral valve replacement is presented. This was diagnosed by two-dimensional and pulsed Doppler echocardiography, and confirmed at cardiac catheterization.

Quantification and toxicity of group A streptococcal pyrogenic exotoxins in an animal model of toxic shock syndrome-like illness

Toxic shock-like syndrome isolates of group A streptococci were evaluated for production of pyrogenic exotoxins (also called SPEs, scarlet fever toxins, and erythrogenic toxins). The isolates were consecutively obtained during 1987 and 1988. Of these isolates, 23 of 26 made SPE type A, 10 of 26 made SPE B, and 8 of 26 made SPE C. SPE A was produced in significantly greater amounts than SPEs B and C (3.2 micrograms/ml of culture fluid compared with 0.7 and 0.6 microgram/ml, respectively). SPE A, administered in miniosmotic pumps implanted subcutaneously in rabbits, was significantly more toxic than SPE C; seven of eight rabbits succumbed after challenge with 150 or 300 micrograms of SPE A, compared with one of six after challenge with SPE C.

Studies on the submicrosomal fractions of bovine oligodendroglia: lipid composition and glycolipid biosynthesis

Oligodendroglia were isolated from bovine brain, and a "crude" microsomal fraction obtained from cell homogenates was subfractionated into myelin (MP), plasma membranes (PM), Golgi (GF), smooth (SER) and rough (RER) endoplasmic membranes using discontinuous-sucrose gradient centrifugation. The submicrosomal fractions were characterized by ultrastructural examination and analysis of the specific organelle markers. The myelin and plasma membrane rich fractions contained characteristically the highest amounts of the lipid with lower mole percentages of total phospholipids and phosphatidylcholine, and higher concentrations of phosphatidylethanolamine (+ plasmalogens), cholesterol and galactolipids. Considerable amounts of the typical myelin galactolipids (galacto-cerebrosides, sulfatides and monogalactosyl diglycerides) were also found in the Golgi fraction (GF). The GF fraction had the greatest enrichment of glycolipid-forming galactosyltransferases, and the distribution of these enzymes correlated well with that of the Golgi marker enzymes. The results give evidence that intracellular Golgi apparatus of oligodendroglia is rich in the myelin-specific lipids, and suggest its involvement in the synthesis and processing of myelin lipids.

Comparison between lidocaine and bupivacaine as local anesthetics with diflunisal for postoperative pain control after lower third molar surgery

The effect of lidocaine and bupivacaine on postoperative pain were compared in a double blind crossover study. Diflunisal (500 mg) was used as an analgesic and given before commencement of the surgical procedure.Bilateral impactions of lower third molars were removed on two occasions, four weeks apart, in a sample of 26 Chinese patients. One local anesthetic was used on one occasion and the alternate on the second. Pain intensity was indicated on a visual analogue scale hourly for eight hours, beginning one hour after the start of surgery.Pain at each postoperative hour was lower after bupivacaine and more patients indicated little or no pain after bupivacaine than after lidocaine. This was not reflected in patients' preference: 12 preferring lidocaine, 11 bupivacaine, and 3 indicating no preference, an important reason being a shorter period of numbness with lidocaine.Although diflunisal was given preoperatively, the postoperative course was not complicated by alveolitis in any case.While bupivacaine plus diflunisal resulted in less postoperative pain than lidocaine plus diflunisal, some patients were willing to sustain some pain after oral surgery if sensation was regained sooner.

A comparison of the incidence and nature of cardiac dysrhythmias occurring during enflurane and isoflurane anaesthesia for dental surgery

The incidence and nature of dysrhythmias with equipotent concentrations of enflurane and isoflurane during dental surgery were compared. Seventy-six Chinese patients between 17-30 years, of ASA Grade I, randomly received either enflurane or isoflurane with N2O and O2 for spontaneous ventilation during third molar extractions. The cardiac rhythm and the blood pressure were continuously monitored during the procedure. The incidence of dysrhythmias with both enflurane and isoflurane was low and the difference not statistically significant. During surgery one patient exhibited unifocal ventricular ectopics with isoflurane. Sinus tachycardia was common with both agents. No life-threatening dysrhythmias were seen with either agent and no clinically significant lowering of blood pressure occurred in association with the exhibited dysrhythmias. In this Chinese population, as in other studies, the incidence of dysrhythmias with both agents was low thus showing no difference between the races.

Radiological diagnosis of leiomyosarcoma of the inferior vena cava

A 46-year-old lady with leiomyosarcoma of the inferior vena cava extending into the hepatic veins and right atrium is described. The diagnosis was made preoperatively by a combination of radiological techniques including computed tomography, inferior vena cavography, arteriography, and two-dimensional echocardiography. The clinical presentation, radiological features and management of this condition are reviewed.

Combined use of warfarin and adjusted subcutaneous heparin during pregnancy in patients with an artificial heart valve

Adjusted subcutaneous heparin was used for thromboembolism prophylaxis during 18 pregnancies in 16 women with an artificial heart valve. Oral warfarin was replaced by subcutaneous heparin as soon as pregnancy was confirmed. The dosage of heparin was adjusted to maintain a partial thromboplastin time at 1.5 times the control value and treatment was administered during the first trimester and the last 3 weeks of gestation. Warfarin was used between the 13th and 37th week. There were no maternal thromboembolic complications and none of the live-born infants showed congenital malformations, indicating that this regimen is effective. However, there were nine spontaneous abortions, including five that occurred in the first 12 weeks. The early abortions were probably related to warfarin exposure at the beginning of pregnancy. The preconception replacement of warfarin by heparin in these patients may be indicated.

An unusual cause of central cyanosis in a patient with rheumatic heart disease

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Comparison of the incidence and nature of cardiac arrhythmias occurring during isoflurane or halothane anaesthesia. Studies during dental surgery

Seventy-six Chinese patients aged between 15 and 30 yr, undergoing 3rd molar extraction, were randomly allocated to two groups. One group received halothane and the other isoflurane. The incidence of arrhythmia during surgery under anaesthesia with isoflurane was significantly less than with halothane. Sinus tachycardia was a significant feature under anaesthesia with isoflurane. Under anaesthesia with halothane, the arrhythmias occurring most frequently during surgery were ventricular ectopics, the commonest being ventricular bigeminy. The frequency and nature of arrhythmias during surgery on right and left sides were similar. In three patients a slight decrease in arterial pressure was recorded in association with the arrhythmia, but on stopping the stimulus, both rhythm and arterial pressure returned to normal. The incidence of arrhythmia with halothane in the Chinese population in this study was significantly higher than that reported previously in non-Chinese patients.

Warfarin versus dipyridamole-aspirin and pentoxifylline-aspirin for the prevention of prosthetic heart valve thromboembolism: a prospective randomized clinical trial

In a prospective, randomized, parallel study, two regimens of platelet-suppressant therapy (PST)--dipyridamole-aspirin and pentoxifylline-aspirin--were compared with standard oral anticoagulation with warfarin in the prevention of prosthetic heart valve thromboembolism. In the entire group of 254 patients followed for 395.6 patient-years, the thromboembolic rate was significantly less in the warfarin group (warfarin vs dipyridamole-aspirin, p less than .005; warfarin vs pentoxifylline-aspirin, p less than .05). Subgroup analysis disclosed that, in patients with isolated mitral valve replacement, warfarin was superior to both of the PSTs with respect to the prevention of thromboembolism (warfarin vs dipyridamole-aspirin, p = .005; warfarin vs pentoxifylline-aspirin, p less than .05). Furthermore, a significant number of our patients could not tolerate the antiplatelet agents. However, in the rare situation in which repeated significant bleeding occurs despite careful adjustment of the dosage of warfarin, PST may be an acceptable alternate method of thromboembolism prophylaxis.

Percutaneous transfemoral catheterization in aortic stenosis with a USCI Sones catheter curve A type 1 (7540)

We report our experience with the use of a USCI Sones catheter curve A type 1 (7540) to cross the aortic valves of 45 patients with clinically significant aortic stenosis. The technique was successful in all our patients with a fluoroscopic time of less than 3 min. A gradient of up to 200 mmHg across the aortic valve area was recorded, and the smallest valve area calculated was less than 0.2 cm2. The method obviated the need for a guidewire and satisfactory left ventriculograms were obtained. No major complication was observed. We conclude that the technique is a simple, rapid, and safe means of obtaining left ventricular hemodynamic and angiographic information in patients with aortic stenosis of various degrees of severity.

Efficacy of low-dose, subcutaneously administered heparin in treatment of pregnant women with artificial heart valves

Between 1979 and 1982, the efficacy of fixed low-dose heparin, administered subcutaneously as thromboembolic prophylaxis, was studied during 14 pregnancies in 10 patients with mechanical heart valves. Calcium heparin (5000 units every 12 hours) was substituted for warfarin during the first trimester and the last month of pregnancy. Although the regimen was well tolerated and was associated with only 14% of first-trimester abortions, five episodes of thromboembolism occurred in four patients. Thus, this fixed, low-dose heparin regimen did not provide adequate thromboembolic prophylaxis in patients with prosthetic heart valves during pregnancy.

Myocardial metabolic effects of intravenous terbutaline in patients with severe heart failure due to coronary artery disease

Intravenous terbutaline, 0.3 mg/kg/min for 30 minutes followed by 0.15 mg/min for 60 minutes, was studied in nine patients with severe heart failure due to documented coronary artery disease. Hemodynamic and myocardial metabolic effects were measured during terbutaline infusion. Cardiac index and stroke index increased, whereas mean pulmonary artery wedge pressure and pulmonary vascular resistance decreased significantly. No significant alterations in aortic oxygen content, coronary sinus oxygen content, myocardial oxygen extraction, and myocardial lactate extraction were observed during terbutaline infusion. No patient developed angina or electrocardiographic changes suggestive of ischemia. These results indicate that intravenous terbutaline infusion, at the dosage employed, produces beneficial hemodynamic effects without a deterioration of myocardial metabolism in patients with heart failure due to coronary artery disease.

Terbutaline infusion in cardiogenic shock: acute hemodynamic effects and clinical response

The effect of terbutaline infusion was studied in six patients with cardiogenic shock due to acute myocardial infarction. Terbutaline was initiated at 3 micrograms/kg/min, and the subsequent infusion rate was adjusted according to heart rate and blood pressure. At 3 hours after infusion arterial pressure increased from 62 +/- 13 mm Hg (mean +/- S.D.) to 89 +/- 13 mm Hg (P less than 0.001), cardiac index increased from 1.38 +/- 0.29 liter/min/m2 to 2.68 +/- 0.47 liter/min/m2 (P less than 0.001), and heart rate increased from 92 +/- 32 beats/min to 112 +/- 29 beats/min (P less than 0.005). Pulmonary artery wedge pressure fell from 24 +/- 7 mm Hg to 17 +/- 3 mm Hg (P less than 0.01), right atrial pressure fell from 12 +/- 4 mm Hg to 6 +/- 3 mm Hg (P less than 0.005), and systemic vascular resistance fell from 1880 +/- 641 dyn-sec/cm5 to 1515 +/- 418 dyn-sec/cm5 (P less than 0.05). In addition, urine flow increased from 4 +/- 6 ml/hr to 314 +/- 237 ml/hr (P less than 0.05), and subjective improvement was noted in all subjects. Undesirable effects observed were hypokalemia (all subjects), supraventricular tachycardia (one subject), and ventricular ectopic beats (three subjects), which responded to potassium replacement and other treatments. All patients required prolonged maintenance infusion to maintain adequate hemodynamic and clinical response. Four patients were weaned off from maintenance therapy after a mean duration of 4.8 days and eventually were discharged from the hospital.(ABSTRACT TRUNCATED AT 250 WORDS)