Suspended particles in wastewater: their optical, sedimentation and acoustical characterization and modeling.

Wastewater regulation and treatment is still a major concern in planetary pollution management. Some pollutants, referred to as particulate matter, consist of very small particles just suspended in the water. Various techniques are used for the suspended particles survey. Few of them are able to provide real-time data. The development of new, real time instruments needs the confrontation with real wastewater. Due its instability, the modeling of wastewater in terms of suspended solids was explored. Knowing the description of real wastewater, we tried to produce a synthetic mixture made of basic organic ingredients. A good agreement in terms of turbidity and settling velocity was observed between the artificial wastewater matrix and the real one. The investigation of the individual contribution of the different compounds to the acoustical signal showed a more complex dependence. Thus the modeling of wastewater with reference to turbidity and settling velocity is not sufficient to describe it acoustically. Further studies should lead to a good comparison of the acoustical and turbidity behavior of wastewater.

Ultrasonic device for real-time sewage velocity and suspended particles concentration measurements.

In the frame of a technological research and innovation network in water and environment technologies (RITEAU, Réseau de Recherche et d'Innovation Technologique Eau et Environnement), our research group, in collaboration with industrial partners and other research institutions, has been in charge of the development of a suitable flowmeter: an ultrasonic device measuring simultaneously the water flow and the concentration of size classes of suspended particles. Working on the pulsed ultrasound principle, our multi-frequency device (1 to 14 MHz) allows flow velocity and water height measurement and estimation of suspended solids concentration. Velocity measurements rely on the coherent Doppler principle. A self developed frequency estimator, so called Spectral Identification method, was used and compared to the classical Pulse-Pair method. Several measurements campaigns on one wastewater collector of the French city of Strasbourg gave very satisfactory results and showed smaller standard deviation values for the Doppler frequency extracted by the Spectral Identification method. A specific algorithm was also developed for the water height measurements. It relies on the water surface acoustic impedance rupture and its peak localisation and behaviour in the collected backscattering data. This algorithm was positively tested on long time measurements on the same wastewater collector. A large part of the article is devoted to the measurements of the suspended solids concentrations. Our data analysis consists in the adaptation of the well described acoustic behaviour of sand to the behaviour of wastewater particles. Both acoustic attenuation and acoustic backscattering data over multiple frequencies are analyzed for the extrapolation of size classes and respective concentrations. Under dry weather conditions, the massic backscattering coefficient and the overall size distribution showed similar evolution whatever the measurement site was and were suggesting a global wastewater particles behaviour. By comparison to sampling data, our data analysis lead to the characterization of two particle groups: the ones occurring during rain events and the ones typical of wastewater under dry weather conditions. Even with already encouraging results on the several weeks of data recorded on several wastewater collectors, the validation of our data inversion method is still under progress.

Obstruction of the bypassed stomach treated with percutaneous drainage: an alternative treatment for selected cases.

Biliopancreatic limb obstruction in Roux-en-Y gastric bypass is an infrequent complication that should be recognized early to avoid the risk of peritonitis and death. In this manuscript, we report a case of acute gastric remnant dilatation secondary to intraabdominal hematoma provoked by trocar injury that was compressing the second portion of duodenum lumen. To treat this problem, we decided on a less invasive treatment consisting of percutaneous decompression of the stomach. The procedure was performed using sonographic guidance with local anesthesia, thus, avoiding a new surgical procedure. In this selected case, percutaneous radiological catheter placement provided an effective decompression of the excluded gastric remnant until spontaneous resolution of the obstruction.

Bariatric Surgery Waiting Lists in Spain.

Bariatric surgery is one of the most common general surgery procedures in countries that, like Spain, have public healthcare systems, but is also one of the procedures for which patients have to wait the longest. The Spanish Society of Obesity Surgery (SECO) conducted a survey to estimate the situation of bariatric surgery waiting lists in Spain's public hospitals and to gather information on a number of related aspects. METHODS: An online survey was sent to the members of the SECO. The survey received 137 visits, all via the click-through link provided, from 52 health centers (47 public and 5 private). The data collected were included in a database and later analyzed using the SPSS18.0 statistical software package. RESULTS: A total of 4724 patients were on bariatric surgery waiting lists (BWLs), at an average of 100 per public hospital. Sixty-eight percent had been waiting for more than 6 months. The mean delay per patient was 397 days, and the longest wait was 1661 days. A further 46.2% of respondents were able to recall cases of patients who in the past 5 years had suffered cardiovascular events with sequelae while awaiting surgery, and 21.2% recalled at least one fatal cardiovascular event in that time. CONCLUSION: Our data revealed an unacceptably long wait for obesity surgery. Notwithstanding the limitations and potential biases of our research, the long wait for surgery in our context inevitably has serious consequences for a potentially significant number of patients.

Carcinoid syndrome misdiagnosed as a malabsorptive syndrome after biliopancreatic diversion.

A case is reported of a woman who developed untreatable diarrhea after a prior biliopancreatic diversion (BPD), attributed to the malabsorptive component. Abdominal ultrasound incidentally found focal liver lesions. On fine needle aspiration biopsy, atypia was found, and these hepatic lesions were resected with free margins. The specimen showed liver metastases of an aggressive malignant neuroendocrine neoplasm. The primary site was subsequently identified to be in the pancreas. The physician and surgeon must realize that non-related diseases can develop after bariatric surgery, as in the general population.

[Mesenteric panniculitis: experience in our center]. / Paniculitis mesentérica: experiencia en nuestro centro.

Although several etiological factors have been associated with mesenteric panniculitis, the exact etiology in some cases remains unknown. Herein, we present a retrospective analysis of 8 patients affected with this disorder performed between May 2000 and December 2006. In our series the mean age at which patients presented was 63 years. The majority of the patients were male (with a male: female ratio of 3:1). The most common clinical manifestations were abdominal pain (n = 4) and asthenia (n = 4). Three cases presented with obstructive symptoms and three had a history of abdominal surgery. Notably, seven had a background of tobacco use (five smokers and two ex-smokers) and one patient developed follicular lymphoma. A literature research was carried out to analyze our results and formulate a new hypothesis. In our opinion, we believe that the study of causal factors such as tobacco and its components is required due to the strong association found in this study.

Recurrence of inflammatory pseudotumor in the distal bile duct: lessons learned from a single case and reported cases.

Inflammatory myofibroblastic tumors (IMTs) or inflammatory pseudotumors (IPs) have been extensively discussed in the literature. They are usually found in the lung and upper respiratory tract. However, reporting of cases involving the biliopancreatic region has increased over recent years. Immunohistochemical study of these lesions limited to the pancreatic head or distal bile duct seems to be compatible with those observed in a new entity called autoimmune pancreatitis, but usually intense fibrotic reaction (zonation) predominates producing a mass. When this condition is limited to the pancreatic head, the common bile duct might be involved by the inflammatory process and jaundice may occur often resembling adenocarcinoma of the pancreas. We have previously reported a case of IMT arising from the bile duct associated with autoimmune pancreatitis which is an extremely rare entity. Four years after Kaush-Whipple resection, radiological examination on routine follow-up revealed a tumor mass, suggesting local recurrence. Ultrasound-guided FNA confirmed our suspicious diagnosis. This present case, as others, suggests that persistent follow-up is necessary in order to prevent irreversible liver damage at this specific location.

Restorative proctocolectomy with an ileoanal pouch: the role of laparoscopy.

OBJECTIVES: The Aim of this retrospective study was to evaluate early experience with laparoscopic restorative proctocolectomy by analyzing the perioperative results of surgical treatment. PATIENTS AND METHODS: Seven major surgeries were performed in six patients with familial adenomatous polyposis and ulcerative colitis. All procedures were performed under laparoscopy at our third-level hospital from June 2003 to October 2004. RESULTS: Mean surgical time was 287.5 +/- 80.7 min, and median blood loss was 300 +/- 249.0 cc. There were no conversions; return of peristalsis began at 32 +/- 12.4 h; average time to first oral intake was 64.0 +/- 32.8 h, and mean duration of hospital stay was 9.3 +/- 1.2 days. There was one case of perineal sepsis due to ileal pouch-anal anastomotic leakage, which was successfully treated with oral intake restriction, parenteral nutrition, and intra-rectal drainage. The most common postoperative complication was postoperative ileus. CONCLUSIONS: We believe that the laparoscopic approach to restorative proctocolectomy may be considerably improved in our center. Particular aspects for improvement include efforts to achieve lower operating and hospitalization times to equate our results with those reported by multicenter studies for laparoscopic colon cancer surgery. In our opinion, learning and further training opportunities should be encouraged to improve surgeon experience in the field of laparoscopy, preferably at centers specializing in restorative proctocolectomy.

Ileoileal intussusception as initial manifestation of Crohn's disease.

Intussusception is usually considered a childhood condition, but it may also be present in adults, where it is more often associated with an underlying pathology. There is no agreement upon the correct treatment of adult intussusception, although surgical intervention is considered necessary. Resection without prior reduction has been the traditional treatment of choice due to the significant risk for malignancy found in most series. We describe an unusual case of intestinal necrosis secondary to ileoileal intussusception caused by Crohn's disease. A long intestinal resection was necessary and the patient was discharged without major complications. Based on the details of this case, the authors emphasize the potential importance of considering individualized treatment of adult intussusception. The practical benefit for reduction of viable bowel in Crohn's patients is the preservation of bowel length.

Usefulness of Clinical Signs and Diagnostic Tests for Suspected Leaks in Bariatric Surgery.

BACKGROUND: The early diagnosis of leakage poses a challenge to bariatric surgeons, who need to suspect and treat it promptly. The aim of this study is to determine the value of clinical signs and complementary tests in its detection. METHODS: Between January 2007 and 2012, 200 patients underwent surgery for pathological obesity. Perioperative variables were collected prospectively, and univariate and multivariate analyses were conducted to study the factors related to leak occurrence and the predictive value of the tests performed. RESULTS: The study includes 172 proximal gastric bypasses and 28 sleeve gastrectomies. Nine patients (4.5 %) had leaks in the immediate postoperative period. Multivariate analyses found that age over 48 years and preoperative BMI > 48 kg/m(2) were the patient-related variables associated with a higher risk of leakage. The clinical variables significantly related to postoperative leaks were heart rate over 100 bpm, leukocytes over 15,000/mm(3) and systolic arterial pressure below 100 mmHg. In patients with a clinical suspicion of leakage (n = 19), 7.7 % of abdominal CT scans returned false negatives, versus 28.6 % for oral methylene blue and 22.2 % for upper gastrointestinal (UGI) Gastrografin swallow [Corrected]. CONCLUSIONS: Bariatric surgery proved to be a safe technique at our medical centre. Patient-related variables associated with a higher risk of leakage were age and BMI. Early clinical signs of leakage were tachycardia, leukocytosis and hypotension. The most reliable diagnostic test was the abdominal CT scan.

A comparative study of the sealing ability of two root canal obturation techniques.

A comparison was made of the ability of two root canal obturating techniques to prevent dye microleakage: gutta-percha lateral condensation and mechanically plasticized gutta-percha (JS Quick-fill). Twenty central incisors were prepared and obturated by each technique. After rendering the teeth transparent, linear dye penetration was found to be 0.48 and 0.52 mm, respectively. The difference between the two techniques was not significant. As for the distribution of the sealing cement (AH26) in the teeth obturated with JS Quickfill, the cement was located in the most peripheral zone of the obturation alongside the dentinal walls, whereas the gutta-percha was found in the central part of the canal obturating material.

An in vivo comparative study of two apex locators.

Two different electronic apex locators were used before extraction to determine working length in 116 root canals belonging to 34 molars. The results were then compared with postextraction working length measurements. The determinations were made before and after eliminating the canal contents and drying the interior. The results showed that 84.8% and 79.3% of the Odometer, and 89.6% and 88.7% of the Endocater readings for dry and nondry canals, respectively, occurred within the two 0.5-mm intervals closest to the apical constriction.

[Laparoscopic cholecystectomy in Spain: multicentric study of 2,432 patients]. / La colecistectomía laparoscópica en España: estudio multicéntrico de 2.432 enfermos.

OBJECTIVES: To evaluate the efficiency of laparoscopic cholecystectomy for the treatment of gallstones. DESIGN: Retrospective/prospective multicentric study undertaken by the Department of Surgical Endoscopy of the Spanish Association of Surgeons. Data were introduced into a computerized protocol. Statistical analysis with SPSS 4.0 applying the Student's T test and Pearson's chi square. PARTICIPANTS: 69 surgeons from 40 Hospitals who have performed laparoscopic cholecystectomies in 2432 patients, diagnosed of gallstones, with an average age of 49 years (9-91) and 80% in women. RESULTS: The operation was completed in 94% of the cases and lasted on an average of 75 minutes (20-120). Surgical findings were 2380 non complicated gallstones, 185 acute cholecystitis (7.6%) and 265 scleroatrophic gallbladders (11%). Intraoperative cholangiography was performed in 9% and gallstones in the common bile duct were diagnosed in 2%, of which 0.3% were treated by laparoscopy and 1% by post-operative endoscopic sphinterotomy Five per cent were converted to laparotomy, of which 29% (1.5% of total patients) were obligatory conversions. Among postoperative complications there were 0.4% lesions due to abdominal puncture, 0.4% lesions of the common bile duct and 2.5% hemorrhages. Post-operative complications were seen in 7.5% of patients. The most frequent complications affected the surgical wounds (3%), whereas bile duct complications represented 0.6% and were most frequent in the series of less than 50 patients. Mortality was 0.12%. Average post-operative hospital stay was 2.5 days (0.5-5). CONCLUSIONS: In Spain, laparoscopic cholecystectomy is an effective and safe procedure with results which are comparable to other multicentric studies published in other countries, with a morbidity-morbility index similar to open cholecystectomy and the great added advantage is the avoidance of laparotomy and its inconveniences (pain, longer hospital stay...) and complications.

[A multicenter clinical trial. Zinc acexamate versus famotidine in the treatment of acute duodenal ulcer. Study Group of Zinc acexamate (new UP doses)]. / Ensayo clínico multicéntrico. Acexamato de zinc versus Famotidina en el tratamiento de la úlcera duodenal aguda. Grupo de estudio del Acexamato de zinc (nueva dosis UP).

A multicentric double-blind trial comparing 600 mg/d of Zinc Acexamate (ACZ) and 40 mg/d of Famotidine (FMT) in the short term treatment of acute duodenal ulcer included 199 patients, diagnosed by endoscopy. One-hundred and five patients received ACZ and 94 FMT, during four weeks. A clinical control took place at two weeks and a second clinical and endoscopic control at the end of the treatment (4 weeks). Complete cicatrization of the ulcer was observed in 56.5% of patients on ACZ and in 69.5% of patients of FMT (N.S.). A reduction of more than 50% of the ulcer diameter was recorded in 78.8% of the ACZ group and in 79.9% of the FMT group. Alcohol and smoking did not influence the results. Both treatments were equally effective in the disappearance of symptoms. The incidence of adverse reactions was very low in both groups (< 5%) and no patient dropped from the trial for this reason. In conclusion, a dosage of 600 mg/d of ACZ has shown to be as effective as 40 mg/d of FMT in the healing of duodenal ulcer.

[Sympathetic nervous activity in cirrhosis: the relationship between peripheral hemodynamics and renal function changes]. / Actividad nerviosa simpática en la cirrosis: relación con la hemodinámica periférica y cambios en la función renal.

The relationship between the activity of the sympathetic nervous system and the systemic and peripheral hemodynamic and renal function changes and the antinatriuretic activity in a group of 30 cirrhotic patients and 8 healthy subjects (control group) was investigated. Plasma catecholamines (noradrenaline, adrenaline and dopamine), plasma renin activity, plasma aldosterone concentrations, mean arterial pressure, cardiac output, blood volume, right femoral arterial flow (RFAF) and renal function parameters were determined in all the participants. Cyclic GMP urinary excretion (cV-UGMP) was used as an indirect index of systemic nitric oxide production. The plasma concentration of noradrenaline was greater in the patients than in the control group and was directly correlated with other vasopressor and antinatriuretic systems, RFAF, cV-UGMP, the degree of hepatic failure studied by the Pugh score and was inversely correlated with creatinine clearance and urinary sodium excretion. On Cox regression analysis, only the RFAF, creatinine clearance and plasma adrenaline concentration remained independently associated with plasma noradrenaline levels. Furthermore, plasma noradrenaline was significantly higher in patients with greater hyperdynamic circulation. These results indicate that extrasplanchnic vasodilatation substantially contributes to sympathetic nervous hyperactivity which may significantly influence in the renal function changes observed in these patients.

Frequency of abnormal esophageal acid exposure in patients eligible for bariatric surgery.

BACKGROUND: Obesity and gastroesophageal reflux disease (GERD) are both high-prevalence diseases in developed nations. Obesity has been identified as an important risk factor in the development of GERD. The objective of this study was to determine the frequency of abnormal esophageal acid exposure in patients candidate for bariatric surgery and its relationship with any clinical and endoscopic findings before surgery. METHODS: Data collected from a group of 88 patients awaiting bariatric surgery included a series of demographic variables and symptoms typical of GERD. The tests patients underwent included manometry, pH monitoring, and upper gastrointestinal endoscopy. Univariate and multivariate analyses were conducted on the variables related to the onset of reflux. RESULTS: Esophageal pH monitoring tests were positive in 65% of the patients. Manometries showed lower esophageal sphincter hypotonia in 46%, while 20% returned abnormal upper endoscopy results. Out of the 45% of patients who were asymptomatic or returned normal endoscopies, half returned positive esophageal pH tests. In turn, among the 55% of patients who had symptoms or an abnormal upper endoscopy, three quarters had pH tests that diagnosed reflux. pH tests were also positive in 80% of symptomatic patients and 100% of patients with esophagitis (P<.042). No statistically significant relationship was found between body mass index, sex, age, manometry, or hiatus hernia and the positive pH monitoring. CONCLUSION: Frequency of abnormal esophageal acid exposure among obese patients is high. There is a relationship between the presence of symptoms and reflux. But the absence of symptoms does not rule out the presence of abnormal esophageal function tests.

Mycobacterium africanum, an emerging disease in high-income countries?

BACKGROUND: Mycobacterium africanum is a cause of tuberculosis (TB) that has mainly been described in Africa, but immigration and travel patterns have contributed to the spread of the disease to other countries. METHODS: We retrospectively reviewed TB cases due to M. africanum during 2000-2010 in seven Spanish hospitals. Selected clinical charts were reviewed using a predefined protocol that included demographical, clinical and microbiological data and outcome. RESULTS: Although 57 cases were diagnosed, only 36 clinical charts were available for review: 82.8% were men and the mean age was 31.6 years (range 12-81). Forty-four cases were from Africa, 1 from the Philippines, 1 from India, and 4 from Spain, while the country of origin was unknown in 7 cases. The most frequent site of infection was the lung (58.3%). Four cases (6.9%) were resistant to at least one first-line anti-tuberculosis drug. CONCLUSIONS: Disease due to M. africanum in industrialised countries is mainly associated with immigration from endemic areas, although some cases also occur among native-born populations.