Control of disinfection and halogenated disinfection byproducts by the electrochemical process.

The aim of this study was to investigate some aspects of the performance of electrochemical process as an alternative disinfection strategy, while minimising DBPs, for water purification. The study of electrochemical processes has shown free chlorine to be produced, but smaller amounts of stronger oxidants, such as ozone, hydrogen peroxide and OH radicals (*OH), were also generated. The formation of mixed oxidants increased with increasing electric conductivity, but was limited at conductivities greater than 0.6 mS/cm. Using several microorganisms, such as E. coli and MS2 bacteriophage, inactivation kinetic studies were performed. With the exception of free chlorine, the role of mixed oxidants, especially OH radicals, was investigated for enhancement of the inactivation rate. Additionally, the formation and reduction of DBPs was studied by monitoring the concentration of haloacetic acids (HAAs) during the process.

Disinfection and oxidation of sewage effluent water using ozone and UV technologies.

This study was aimed at exploring the reclamation of sewage treatment plant effluent water (SEW) as an alternative water resource. For the oxidation of SEW, an ozone-UV system, based on the results of the combined ozone/UV process performed in our previous study, was set up under practical conditions, including a series type, continuous mode, semi-pilot scale operation (1.5 m3/d). As a result, the serial contact of the ozone and UV reactors showed lower CODCr and TOC removal efficiencies. However, these were greatly enhanced by recycling the water flow of the ozone-UV system at 40Q, as a result of the improvements in the transferred ozone dose in the ozone reactor and the contact efficiency between photons and ozone in the UV reactor, which approached that achieved in the combined ozone/UV process. For the disinfection of SEW, carried out in a syringe-type batch reactor, the increase of instantaneous ozone demand (ozone ID) led to a higher inactivation efficiency, an increased UV transmittance due to ozonation, and an enhanced inactivation rate of E. coli in the UV reactor. Additionally, it was concluded that the ozone/UV process could overcome the limitations of the ozone alone and UV alone processes for the reclamation of sewage effluent water.

Catalyzed ozonation process with GAC and metal doped-GAC for removing organic pollutants.

The purpose of this study was to investigate the catalytic role of granular activated carbon (GAC), and metal (Mn or Fe) doped-GAC, on the transformation of ozone into more reactive secondary radicals, such as hydroxyl radicals (*OH), for the treatment of wastewater. The GAC doped with Mn showed the highest catalytic performance in terms of ozone decomposition into OH radicals. Likewise, activated carbon alone accelerated the ozone decomposition, resulting in the formation of *OH radicals. In the presence of promoters, the ozone depletion rate was enhanced further by the Mn-GAC catalyst system, even under aqueous acidic pH conditions.

Microinvasive video-assisted thoracoscopic sympathicotomy for primary palmar hyperhidrosis.

BACKGROUND: Although video-assisted thoracoscopic surgery for palmar hyperhidrosis is now widely accepted as the approach of choice, the optimal technique has remained a subject of controversy. We have used 2-mm dual port video-assisted thoracoscopic sympathicotomy for primary palmar hyperhidrosis. This study evaluates the short-term results of the technique. METHODS: A retrospective review was carried out of 45 patients, 20 men and 25 women, with a mean age of 24.2 years. In the period from April 1998 to August 1999, 90 consecutive video-assisted sympathicotomy for primary palmar hyperhidrosis either in isolation (n = 56) or in combination with axillary and plantar hyperhidrosis (n = 34) was performed. The mean follow-up period was 11.3 months. Attention was focused on patient's satisfaction, complications, and morbidity. RESULTS: Dry limbs were immediately achieved in all patients after surgery. There was no operative mortality and one case of transient Horner's syndrome developed. Eight of 20 with plantar hyperhidrosis showed simultaneous improvement. The overall mean satisfaction rate was 92% +/- 2% with a median 93% improvement using a visual linear analogue scale from 0% (poor) to 100% (excellent). Only 2 patients were dissatisfied with the operative results owing to compensatory hyperhidrosis, which occurred in 25 patients and improved in 20 patients within the follow-up period. CONCLUSIONS: The video-assisted thoracoscopic sympathicotomy with 2-mm endoscope is a speedy and safe way of controlling hyperhidrosis with excellent cosmetic results while minimizing complications.

Prenatal diagnosis of severe tricuspid insufficiency in Ebstein's anomaly with pulmonary atresia and intact ventricular septum: a case report.

Pulmonary atresia with intact ventricular septum is an uncommon congenital cardiac anomaly which very often present varying degrees of downward displacement and dysplasia of the tricuspid valve. A 23-year-old woman was referred at 23 weeks' gestation because of fetal cardiomegaly detected by routine ultrasonography. Ebstein's anomaly with pulmonary atresia was diagnosed by fetal echocardiography. On pulsed Doppler examination, a severe tricuspid regurgitation was detected. Pulmonary atresia was suspected, as forward flow was not detected into pulmonary artery. The fetus was terminated at 25 weeks. At the postmorterm examination Ebstein's anomaly with pulmonary atresia and intact ventricular septum were confirmed. The finding of right atrial enlargement on an early sonogram should prompt the search for tricuspid valve abnormalities with tricuspid regurgitation and the presence or development of pulmonary atresia or stenosis. With the information provided, early detection of tricuspid valve disease should be possible so that the option of therapeutic abortion can be offered.

Video assisted thoracoscopic ligation of patent ductus arteriosus. Technique of sliding loop ligation.

Variant video-assisted thoracoscopic surgical technique for closure of patent ductus arteriosus has been introduced. Although the endoscopic clipping device may be a preferred method for interruption of the patent ductus arteriosus, there is always the risk of inadequate clip placement and limitation of application in width of ductus arteriosus. In an effort to overcome this problem we have used a self-made endoscopic loop ligation in 10 patients and herein report the method. Only a small window and one port of access are necessary to dissect the patent ductus arteriosus from the surrounding tissues and to apply the extracorporeally created sliding loop. Successful ligation without shunt is obtained in all cases. The technique is simple and safe even in the presence of a wide ductus.

Differentially-altered vascular guanylate cyclase isoforms in experimental hypertensive rats.

Pathophysiological implications of the vascular nitric oxide (NO)/cGMP pathway were investigated in various rat models of hypertension. The expression of brain and endothelial constitutive NO synthases (bNOS, ecNOS) was determined by Western blot analysis, and the biochemical activity of soluble and particulate guanylate cyclases (GC) was assessed by the amount of cGMP generated in the thoracic aortae of rats with deoxycorticosterone acetate (DOCA)-salt, two-kidney, one dip (2K1C), and spontaneous hypertension (SHR). Plasma nitrite/ nitrate levels were decreased in DOCA-salt and 2K1C hypertension, and increased in SHR. The vascular expression of bNOS as well as that of ecNOS was decreased along with tissue nitrite/nitrate contents in DOCA-salt and 2K1C hypertension. The expression of both bNOS and ecNOS was increased in SHR with concomitant changes of tissue nitrite/nitrate contents. The activity of soluble GC was decreased, and that of particulate GC was increased in DOCA-salt hypertension. The soluble GC activity was increased, while the particulate GC activity was not affected in 2K1C hypertension. The soluble GC activity was not significantly changed, but the particulate GC activity was decreased in SHR. These results indicate that the high blood pressure is associated with differentially-altered vascular NO/cGMP pathway in different models of hypertension.

Anomalous origin of the left anterior descending coronary artery from the pulmonary trunk associated with type B interrupted aortic arch.

An extremely rare congenital anomaly of the coronary circulation in a neonate with type B interrupted aortic arch is reported in which the left anterior descending coronary artery arose from the pulmonary trunk and the right and left circumflex coronary arteries from the aorta. An anomalous coronary artery was demonstrated by selective pulmonary angiography and then confirmed at necropsy.

Long-term effects of pentobarbital anesthesia on the atrial natriuretic peptide system in rats.

A long-term effect of pentobarbital treatment on the storage and release of atrial natriuretic peptide (ANP) was investigated in rats. The experimental group was treated with pentobarbital (50 mg/kg, ip), and the control group was injected with the vehicle only. They were used one week after the treatment. Male and female rats were used separately to see if there exists a sex difference in the response to pentobarbital. In male rats, the plasma ANP measured in a conscious state was significantly higher in the experimental group than in the control. The ANP content as well as the number of specific granules in the atrial tissue was significantly lower in the experimental group. In response to extracellular volume expansion (VE), amounting up to 5% of the body weight over 30 min, while the plasma ANP increased in the control, it did not significantly change in the experimental group. Urinary responses to the exogenous infusion of ANP did not differ in magnitude between the two groups. In female rats, neither the plasma level nor the atrial content of ANP (or the atrial granularity) was different between the experimental and control groups. Nor did the increase of plasma ANP in response to VE differ in magnitude between the two groups in female rats. These results indicate that pentobarbital may have a long-term effect on the storage and release of ANP.

Surgical model of volume overload-induced ventricular myocardial hypertrophy (VHvo) to study a clinical problem in humans.

Cardiac patients with aortic or mitral valve incompetence often suffer from VHvo and are at higher risk of surgery compared to other patients undergoing heart surgery. Hypertrophied hearts are known to have altered metabolism and function. Therefore, it is imperative to use hearts with similar pathology as found in clinical patients when studying ways to better protect them. We herein report a model of VHvo developed in our laboratory. Pigs (n = 10) weighing 21 kg were anesthetized, intubated, and mechanically ventilated in dorsal recumbency. Bilateral femoral arterio-venous side-to-side anastomoses were created at least twice the diameter of the vessels. Patency was confirmed and the animals grew to maturity with this pathology, at which time they were sacrificed. Severe hypertrophy was documented with significantly greater heart weight to body weight ratio, LV free wall thickness, and septum. This surgical model of VHvo is associated with minimal complications and no pericardial adhesions. This allows for accurate metabolic and functional heart studies to be conducted at a later date.