Model-based comparison of two ways to enhance WWTP capacity under stormwater conditions.

Two different approaches to increase the fraction of combined water treated in the wastewater treatment plant (WWTP) which would otherwise contribute to combined sewer overflows (CSO) are presented and compared based on modelling results with regard to their efficiencies during various rain events. The first option is to generally increase the WWTP inflow according to its actual capacity rather than pre-setting a maximum that applies to worst case loading. In the second option the WWTP inflow is also increased, however, the extra inflow of combined water is bypassing the activated sludge tank and directly discharged to the secondary clarifier. Both approaches have their advantages. For the simulated time series with various rain events, the reduction of total COD load from CSOs and WWTP effluent discharged to the receiving water was up to 20% for both approaches. The total ammonia load reduction was between 6% for the bypass and 11% for inflow increase. A combination of both approaches minimises the adverse effects and the overall emission to the receiving water.

Arsenic(III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California.

Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The communities were composed primarily of Ectothiorhodospira-like purple bacteria or Oscillatoria-like cyanobacteria. A pure culture of a photosynthetic bacterium grew as a photoautotroph when As(III) was used as the sole photosynthetic electron donor. The strain contained genes encoding a putative As(V) reductase but no detectable homologs of the As(III) oxidase genes of aerobic chemolithotrophs, suggesting a reverse functionality for the reductase. Production of As(V) by anoxygenic photosynthesis probably opened niches for primordial Earth's first As(V)-respiring prokaryotes.

Dissimilatory arsenate and sulfate reduction in sediments of two hypersaline, arsenic-rich soda lakes: Mono and Searles Lakes, California.

A radioisotope method was devised to study bacterial respiratory reduction of arsenate in sediments. The following two arsenic-rich soda lakes in California were chosen for comparison on the basis of their different salinities: Mono Lake (approximately 90 g/liter) and Searles Lake (approximately 340 g/liter). Profiles of arsenate reduction and sulfate reduction were constructed for both lakes. Reduction of [73As]arsenate occurred at all depth intervals in the cores from Mono Lake (rate constant [k] = 0.103 to 0.04 h(-1)) and Searles Lake (k = 0.012 to 0.002 h(-1)), and the highest activities occurred in the top sections of each core. In contrast, [35S]sulfate reduction was measurable in Mono Lake (k = 7.6 x10(4) to 3.2 x 10(-6) h(-1)) but not in Searles Lake. Sediment DNA was extracted, PCR amplified, and separated by denaturing gradient gel electrophoresis (DGGE) to obtain phylogenetic markers (i.e., 16S rRNA genes) and a partial functional gene for dissimilatory arsenate reduction (arrA). The amplified arrA gene product showed a similar trend in both lakes; the signal was strongest in surface sediments and decreased to undetectable levels deeper in the sediments. More arrA gene signal was observed in Mono Lake and was detectable at a greater depth, despite the higher arsenate reduction activity observed in Searles Lake. A partial sequence (about 900 bp) was obtained for a clone (SLAS-3) that matched the dominant DGGE band found in deeper parts of the Searles Lake sample (below 3 cm), and this clone was found to be closely related to SLAS-1, a novel extremophilic arsenate respirer previously cultivated from Searles Lake.

Acute adrenocortical insufficiency due to heparin-induced thrombocytopenia with subsequent bilateral haemorrhagic infarction of the adrenal glands.

A 56 year old male developed bilateral massive adrenal haemorrhage (BMAH) resulting in chronic adrenal insufficiency in the course of heparin-induced thrombocytopenia (HIT)-syndrome. Thrombosis of the central adrenal vein (CAV) with subsequent adrenal haemorrhagic infarction is the most probable cause of the rare association of HIT and BMAH. The exorbitantly high catecholamine plasma levels within the CAV in addition to immunogenic platelet activation are discussed as possible underlying pathophysiological mechanisms.

Infiltrating angiolipoma of the M. temporalis.

Angiolipomas are rare benign mesenchymal tumours that are distinguished from common lipomas by a marked degree of vascularisation. They are differentiated into non-infiltrating and the even less frequent infiltrating angiolipomas. The present case is the 9th report of an infiltrating angiolipoma of the head and neck. The patient was a 63-year-old man with an infiltrating angiolipoma of the left M. temporalis. Microscopic examination showed univacuolated adipose cells mixed with capillaries invading skeletal muscle. The patient has been free of recurrence since excision of the tumor.

Ultrasound-guided interstitial Nd: YAG laser treatment of voluminous hemangiomas and vascular malformations in 92 patients.

In many cases voluminous vascular anomalies of the head and neck region are still treated with conventional surgery, although neodymium:yttrium-aluminum-garnet (Nd:YAG) laser therapy offers a valuable treatment alternative. Ninety-two patients with voluminous hemangiomas and vascular malformations were treated with interstitial Nd:YAG laser therapy (power density, 1300 to 3300 W/cm2), partly complemented by a noncontact-mode Nd:YAG laser light application (energy density, 1000 to 2500 J/cm2). The vascular tumors had a diameter of more than 3 cm in at least two dimensions. Treatment was carried out under ultrasound and manual control. Nearly 60% of the patients (n = 55) showed a complete clinical regression. Thirty-three patients (35.8%) had a partial regression and were satisfied with the treatment outcome. Four patients were treated unsuccessfully with the laser, and three of them subsequently underwent conventional surgery. Only nine of the 92 patients (9.8%) showed cosmetic or functional impairments. The results of this first consecutive series study with a retrospective clinical evaluation of the interstitial Nd:YAG laser therapy of voluminous hemangiomas and vascular malformations in a large patient group demonstrate a high effectiveness of this novel therapy modality.

Normal esophageal body function: a study using ambulatory esophageal manometry.

OBJECTIVE: The objective of this study was to establish normative ambulatory manometric data for contractions and contraction propagation in three levels of the esophagus. METHODS: Twenty-five healthy volunteers underwent simultaneous ambulatory 24 h manometry. Concomitant 24 h pH studies were performed to exclude the presence of increased esophageal acid exposure. Pressures were recorded over a complete circadian cycle while patients continued with their normal lifestyles including eating and sleeping. Data were analyzed with a software program that was previously modified and validated and that enables quantitation of contractions in terms of efficacy. RESULTS: The frequency of contractions was lowest during sleep, was increased when awake, and was highest during meals. Contraction amplitude increased during meals, providing a greater propulsive force for bolus transport. Similarly, the prevalence of peristaltic waves varied according to different physiologic states, ie., while eating, upright, awake, and sleeping. An increased amplitude and prevalence of peristalsis resulted in an increase in manometric efficacy during meals. CONCLUSIONS: This study provides normative data for ambulatory manometry for comparison when studying patients with disease.

[Argon plasma coagulation in endoscopic therapy of CREST syndrome associated upper gastrointestinal hemorrhage]. / Die Argonplasmakoagulation in der endoskopischen Therapie einer CREST-Syndrom-assoziierten oberen gastrointestinalen Blutung.

We report on the case of a 55-year-old patient suffering from progressive systemic sclerosis (PSS). The patient was sent to our department when clinical symptoms of an acute upper gastrointestinal hemorrhage occurred. Upper endoscopy showed a watermelon stomach and fresh blood in the stomach. The presence of teleangiectasias in the antrum could be proved histologically. Since the teleangiectasias found in the antrum were the only possible source of the hemorrhage three sessions of endoscopic argon plasma coagulation were performed. Macroscopically, a nearly complete disappearance of teleangiectasias could be achieved. After a follow-up of six months, there have been no clinical signs of another hemorrhage episode. This case shows that the existence of gastrointestinal teleangiectasias should be considered when chronic anemia or acute gastrointestinal hemorrhage occur in patients with PSS. Further it is demonstrated that even extended gastrointestinal teleangiectasias can be successfully treated by endoscopically performed argon plasma coagulation.

Is Barrett's metaplasia the source of adenocarcinomas of the cardia?

OBJECTIVE: To investigate the prevalence of Barrett's esophagus in patients with adenocarcinomas located at the gastroesophageal junction. DESIGN: A case series of patients who underwent esophagogastrectomy for adenocarcinoma was retrospectively reviewed. Tumors were grouped by location as esophageal, cardiac, and subcardiac, and the prevalence of specialized intestinal metaplasia in the histological specimens was determined. SETTING: A university department of surgery that specializes in esophageal diseases. PATIENTS: One hundred patients with adenocarcinoma of the esophagus, cardia, or proximal stomach. MAIN OUTCOME: Cardiac adenocarcinomas were associated with Barrett's esophagus in 42% of the patients. RESULTS: Specialized intestinal metaplasia was identified in the histological sections from the resected specimen in 42% (13/31) of cardiac adenocarcinomas and in 79% (38/48) of esophageal adenocarcinomas but in only 5% (1/21) of subcardiac adenocarcinomas. The preoperative endoscopic biopsy results concurred with the final diagnosis of Barrett's esophagus in 33 of the 38 esophageal tumors, six of the 13 cardiac tumors, and the one subcardiac tumor but failed to detect specialized intestinal metaplasia in 54% (7/13) of cardiac tumors. Cardiac tumors were associated with shorter lengths of Barrett's mucosa than esophageal tumors (2.7 +/- 1.8 cm vs 7.4 +/- 3.4 cm, P < .01). The Barrett's metaplasia was dysplastic in 36 of the 38 esophageal tumors, 10 of the 13 cardiac tumors, but not in the subcardiac tumor. CONCLUSIONS: Adenocarcinomas located at the gastroesophageal junction were associated with Barrett's metaplasia in nearly one half of the patients. The length of the Barrett segment tends to be short and may be missed during endoscopy. The presence of high-grade dysplasia within Barrett's mucosa supports a barrett's origin for half of the adenocarcinomas arising at this location.

The effect of symptoms and nonspecific motility abnormalities on outcomes of surgical therapy for gastroesophageal reflux disease.

The outcome of Nissen fundoplication in patients with a nonspecific motility abnormality compared with the outcome in patients with normal motility is unknown. One hundred consecutive patients who underwent primary Nissen fundoplication were evaluated before and a median of 50 months after operation, with emphasis on the presence of a preoperative motility disorder and its relationship to preoperative and postoperative symptoms. Compared with patients who had normal motility, patients with a nonspecific motility abnormality had a greater prevalence and severity of heartburn and regurgitation before operation. These patients also had a greater esophageal exposure to gastric juice on pH monitoring as a result of poorer esophageal clearance function. The prevalence and severity of preoperative dysphagia was not related to the presence of a motility disorder. A 90% or a 95% actuarial success rate was achieved in the relief of heartburn and regurgitation over a 96-month period in patients with and without a motility abnormality. The overall actuarial success rate was 93%. Dysphagia was rarely caused or made more severe by the procedure; if present before the operation, it was relieved in most patients. The prevalence of persistent postoperative dysphagia was similar in patients with and without a motility abnormality. The success of Nissen fundoplication in properly selected patients is not affected by the presence of a nonspecific motility disorder.

Selection of patients for curative or palliative resection of esophageal cancer based on preoperative endoscopic ultrasonography.

OBJECTIVE: To assess the accuracy of pretreatment staging and the potential of using endosonographic findings to select patients for curative or palliative resection by comparing the preoperative endosonographic and computed tomographic (CT) findings with the histology of the surgical specimen. METHODS: Forty-two patients referred to our clinic with esophageal carcinoma underwent preoperative upper endoscopy with biopsy, endosonography, thoracic CT, and abdominal CT. Based on endoscopic ultrasonographic findings, patients with early-stage disease underwent en-bloc esophagogastrectomy, whereas those with advanced disease had a palliative transhiatal esophagectomy. Exceptions included patients with poor physiologic reserve who were treated by the transhiatal route. RESULTS: In eight patients, we were unable to pass the ultrasonographic endoscope. Seven of these eight had transmural tumors with nodal involvement on histologic study. Tumor length, based on endosonographic measurements, was correctly predicted in 34 patients (85%). Extent of wall penetration was accurately predicted in 26 (76%) of the 34, and regional lymph node status was accurately predicted in 28 (82%) of the 34. Of the patients with sonographic wall penetration, 80% had histologic evidence of one or more positive nodes. Using the WNM staging system, endoscopic ultrasonography correctly staged the cancer in 68% of the patients. Three patients were treated with an inappropriate procedure. CONCLUSION: Endosonography is a reliable method for the preoperative staging and selection of patients for curative or palliative resection. Endosonographic wall penetration appears to be a critical factor in determining tumor spread.

Value of physiologic assessment of foregut symptoms in a surgical practice.

BACKGROUND: The aim of this study was to evaluate the reliability of symptoms in the diagnosis of gastroesophageal reflux disease and esophageal motility disorders as assessed by functional tests. METHODS: In 365 patients referred for suspected esophageal functional disease, symptomatic assessment was compared with the results of esophageal manometry and ambulatory 24-hour pH monitoring of the distal esophagus. RESULTS: Based on the patients' chief complaint, the symptomatic diagnosis was gastroesophageal reflux (44%), esophageal motor disorder (26%), chest pain of esophageal origin (9%), reflux and aspiration (8%), and abdominal pathology (12%). The symptomatic diagnosis was considerably altered by the results of the esophageal function tests: gastroesophageal reflux and motility disorders were found in all symptomatic diagnostic groups and a large number of patients in each group tested normal. The sensitivity and specificity of symptom-based diagnoses for functional disease were low. CONCLUSIONS: The results of this study showed that symptoms are an unreliable guide of esophageal abnormality, illustrating the need for objective testing in these patients, particularly to avoid inappropriate medical or surgical therapy.

Pharyngeal swallowing. The major factor in clearance of esophageal reflux episodes.

OBJECTIVE: This study defined the clearance mechanisms of naturally occurring reflux episodes in normal subjects and patients with gastroesophageal reflux disease. SUMMARY BACKGROUND: Previous studies on acid clearance have been performed in the laboratory setting in supine subjects using acid instillation and stationary motility. The mechanisms of clearance have not been studied using ambulatory pH and motility monitoring. METHODS: A new system capable of monitoring simultaneously for 24 hours pharyngeal pressure, esophageal motility, and pH was used to study the clearance of naturally occurring reflux episodes in 10 normal subjects and 18 patients with gastroesophageal reflux disease. Esophageal contraction waves were classified as primary (i.e., initiated by a pharyngeal swallow) and secondary (i.e., unrelated to a pharyngeal swallow). RESULTS: A total of 1288 reflux episodes were analyzed, during which 2781 contraction waves occurred. Clearance (i.e., restoration of pH to > 4) occurred after primary peristalsis in 83% of reflux episodes. An additional 11% were cleared by pharyngeal swallows without an esophageal body response. Secondary waves were rare and when they occurred, only 19% were peristaltic. Secondary peristalsis cleared only 9 of the 1288 reflux episodes. Patients and normal subjects cleared reflux episodes similarly. Baseline swallowing frequency was 0.87/min during the daytime and increased to 2.59/min (p < 0.01) during daytime reflux episodes. Swallowing frequency in response to nighttime reflux episodes was less (1.42/min; p < 0.05). CONCLUSIONS: Pharyngeal swallowing is the most important mechanism for esophageal acid clearance. Secondary waves are rare, usually disorganized, and unimportant in clearing a reflux episode. During sleep, the mechanisms of clearance are depressed.

Manual verification of computer analysis of 24-hour esophageal motility.

The application of solid-state technology to intraesophageal pressure monitoring over an entire circadian cycle has resulted in large amounts of data that require computer analysis. Recently available commercial software has yet to be validated. The aim of this study was to compare the analysis of ambulatory esophageal manometry by an automated computer program with manual analysis and make the software modifications necessary to validate the automated system for clinical use. Computer-aided analysis of a large number of esophageal contractions recorded during ambulatory esophageal manometry was compared with manual analysis by four experienced physicians. Good correlations were found between manual and computerized measurements of contraction amplitude and duration (r = 0.99 and r = 0.73, respectively). Software modifications resulted in correct identification of 94% of contractions and correct classification of 93.3% of these waves as peristaltic or simultaneous. These results demonstrate that the evaluated program for automated analysis of ambulatory esophageal manometry is accurate and reliable for research and clinical applications.

Functional foregut abnormalities in Barrett's esophagus.

The factors predisposing to the development of Barrett's esophagus in patients with gastroesophageal reflux disease are unclear. We compared symptoms, esophageal acid and alkaline exposure (pH < 2, < 3, < 4, and > 7), lower esophageal sphincter resistance, esophageal clearance function, the gastric secretory state, gastric emptying, and duodenogastric reflux in 15 patients with Barrett's esophagus with 24 patients with esophagitis and with 22 normal subjects. Compared with patients with esophagitis, patients with Barrett's esophagus had less heartburn and regurgitation but had an increased frequency and duration of reflux episodes and percent time pH less than 2, less than 3, less than 4, and pH greater than 7 on ambulatory 24-hour esophageal pH monitoring. This was associated with a decreased lower esophageal sphincter resistance, a decreased contraction amplitude in the distal area of the esophagus, an increased frequency of nonperistaltic contractions and contractions less than 30 mm Hg on 24-hour ambulatory esophageal motility monitoring, increased basal and stimulated gastric acid secretion, and a higher prevalence of excessive duodenogastric reflux. These data show that despite less symptoms patients with Barrett's esophagus have a markedly increased esophageal acid and alkaline exposure compared with patients with esophagitis. This appears to be because of persistent reflux of highly concentrated gastric acid and duodenal contents across a mechanically defective lower esophageal sphincter in combination with inefficient esophageal clearance function.

Functional analysis of plasma fibronectin with special consideration of binding interferences.

So far, soluble fibronectin has been quantitated mostly by immunological techniques. In this investigation we show that an immunological assay provides reliable results only with intact fibronectin. Fibronectin fragments resulting from proteolysis give rise to falsely raised values. We present four functional tests based on the sandwich (ELISA) technique on microtitre plates. These quantify fibronectin on the basis of its binding capacity to collagen, heparin, fibrin and carboxy-group-modified IgG with high sensitivity, specificity and precision. Analysis of the bioactivity spectrum of intact fibronectin is not disturbed by fibronectin fragments. Furthermore we demonstrate interferences, in particular between heparin and collagen in their mutual binding to fibronectin. This provides new indications of a "substrate activation" of fibronectin.