Differing field methods and site conditions lead to varying bias in suspended sediment concentrations in the Lower Mississippi and Atchafalaya Rivers.

At sites that have been sampled for decades, changes in field and laboratory methods happen over time as instrumentation and protocols improve. Here, we compare the influence of depth- and point-integrated sampling on total, fine (< 0.0625 mm), and coarse (≥ 0.0625 mm) suspended sediment (SS) concentrations in the Lower Mississippi and Atchafalaya Rivers. Using historical field method information, we identified seven sites to test such differences. We found SS samples collected using point-integration tended to have higher concentrations than those collected using depth-integration. However, the presence and magnitude of the bias were inconsistent across sites. Bias was present at the site with less-than-ideal conditions (i.e., non-trapezoidal channel, non-uniform flow) and non-existent at the ideal site location, indicating the bias between sampling methods depends on site sampling conditions. When present, the bias is greater at higher concentrations and at moderate to high flows. At the less-than-ideal site, point-integrated samples can have 16% (total) and 34% (coarse) higher concentrations than depth-integrated samples. When flow effects are removed, this translates to a bias of 19, 9, and 8 mg per liter for total, fine, and coarse SS. When a change in field methods occurs, comparison samples and a rigorous evaluation of those samples are warranted to determine the proper course of action for a particular site. Often, the effect and solution will not be known until several years of comparison samples have been collected under a variety of hydrologic conditions.

Methodological issues with the assessment of voluntary activation using transcranial magnetic stimulation in the knee extensors.

PURPOSE: The assessment of voluntary activation of the knee extensors using transcranial magnetic stimulation (VATMS) is routinely performed to assess the supraspinal function. Yet methodological scrutiny of the technique is scarce. The aim of the present study was to examine face validity and reliability of VATMS and its two main determinants (superimposed twitch during a maximal voluntary contraction [SIT100%] and estimated resting twitch [ERT]). METHODS: SIT100%, ERT, and VATMS were measured on ten healthy males (age 24 ± 5 years) before and following intermittent isometric fatiguing exercise on two separate occasions. RESULTS: The findings indicated issues regarding the accuracy of ERT and suggested a three-point relationship should not be used to determine ERT. Reliabilities for VATMS, SIT100%, and ERT were acceptable pre- but much weaker post-exercise (especially for SIT100%). Despite statistically significant changes in main neuromuscular variables following the intermittent isometric fatiguing exercise (P < 0.05), when post-exercise reliability was considered, the exercise effect on VATMS was smaller than the smallest detectable change in 18 of the 20 individual tests performed, and for the whole sample for one of two visits. Finally, maximal voluntary contraction was reduced significantly following the neuromuscular assessment (NMA) pre-exercise but recovered during the NMA post-exercise. CONCLUSION: This is the first study to demonstrate a lack of sensitivity of key neuromuscular measurements to exercise and to evidence both presence of neuromuscular fatigue following the NMA in itself, and recovery of the neuromuscular function during the NMA post-exercise. These results challenge the face validity of this routinely used protocol.

Selection of indicator contaminants of emerging concern when reusing reclaimed water for irrigation - A proposed methodology.

Organic and microbial contaminants of emerging concern (CECs), even though not yet regulated, are of great concern in reclaimed water reuse projects. Due to the large number of CECs and their different characteristics, it is useful to include only a limited number of them in monitoring programs. The selection of the most representative CECs is still a current and open question. This study presents a new methodology for this scope, in particular for the evaluation of the performance of a polishing treatment and the assessment of the risk for the environment and the irrigated crops. As to organic CECs, the methodology is based on four criteria (occurrence, persistence, bioaccumulation and toxicity) expressed in terms of surrogates (respectively, concentrations in the secondary effluent, removal achieved in conventional activated sludge systems, Log Kow and predicted-no-effect concentration). It consists of: (i) development of a dataset including the CECs found in the secondary effluent, together with the corresponding values of surrogates found in the literature or by in-field investigations; (ii) normalization step with the assignment of a score between 1 (low environmental impact) and 5 (high environmental impact) to the different criteria based on threshold values set according to the literature and experts' judgement; (iii) CEC ranking according to their final score obtained as the sum of the specific scores; and (iv) selection of the representative CECs for the different needs. Regarding microbial CECs, the selection is based on their occurrence and their highest detection frequency in the secondary effluent and in the receiving water, the antibiotic consumption patterns, and recommendations by national and international organisations. The methodology was applied within the ongoing reuse project SERPIC resulting in a list of 30 indicator CECs, including amoxicillin, bisphenol A, ciprofloxacin, diclofenac, erythromycin, ibuprofen, iopromide, perfluorooctane sulfonate (PFOS), sulfamethoxazole, tetracycline, Escherichia coli, faecal coliform, 16S rRNA, sul1, and sul2.

[QUALICOPC -- primary care study on quality, costs and equity in European countries: the Hungarian branch]. / QUALICOPC -- az alapellátás minoségének, költségének és méltányosságának vizsgálata Európa országaiban: magyarországi ág.

The importance of primary care has already been recognized in the developed countries, where the structure and function of primary care is very heterogeneous. In the QUALICOPC study, the costs, quality and equity of primary care systems will be compared in the 34 participating countries. Representative samples of primary care practices were recruited in Hungary. An evaluation with questionnaire was performed in 222 practices on the work circumstances, conditions, competency and financial initiatives. Ten patients in each practice were also questioned by independent fieldworkers. In this work, the methodology and Hungarian experience are described. The final results of the international evaluation will be analyzed and published later. It is expected that data obtained from the QUALICOPC study may prove to be useful in health service planning and may be shared with policy makers.

A nationwide survey on bariatric surgery in Germany--results 2005-2007.

BACKGROUND: Most studies on bariatric surgery outcomes are performed as clinical trials or reflect the clinical experience in single centers. The status of bariatric surgery in Germany has been examined since January 1st, 2005 with the cooperation of clinics and hospitals at the Institute of Quality Assurance in Surgery at the Otto-von-Guericke University of Magdeburg (Germany). METHODS: In this prospective multicenter observational study, the data obtained for all primary bariatric procedures, including all repeated operations, performed on consecutive patients with morbid obesity at participating hospitals from 2005 to 2007 were prospectively collected using an Internet online data registry. In particular, perioperative characteristics, such as the spectrum of diagnostic measurements, type of surgical procedures, and short- and long-term outcomes, were investigated. RESULTS: During the study period, 629 surgical procedures were performed at 21 hospitals in 2005, 828 procedures at 32 hospitals in 2006, and 1,666 procedures at 35 hospitals in 2007. In 2005 and 2006, gastric banding was the most frequently performed operation, followed by the Roux-en-Y gastric bypass (RYGBP). In 2007, a RYGBP was carried out in 42.1% of all bariatric procedures. Among all patients, 74.4% were female. The mean body mass index (BMI) was 48.5 kg/m(2) in 2005, 48.4 kg/m(2) in 2006, and 48.0 kg/m(2) in 2007. Follow-up data after 12 months were available for 63.8% of the patients in 2005 and 2006; these data showed greater reduction of BMI after malabsorptive rather than restrictive bariatric procedures. The mortality was 0.1% (30 days) and 0.16% (overall). CONCLUSION: As indicated by the worldwide trend, there is an ongoing change from restrictive bariatric procedures to malabsorptive procedures and sleeve gastrectomy. Although the BMIs of German patients undergoing bariatric surgery appear to be substantially higher than those of patients from most other countries, there were no differences in intraoperative and short-term complications or in overall outcomes during follow-up when compared with published studies.

Results of sleeve gastrectomy-data from a nationwide survey on bariatric surgery in Germany.

BACKGROUND: Beginning January 1, 2005, the status and outcomes of bariatric surgery were examined in Germany. Data are registered in cooperation with the An-Institute of quality assurance in surgery at the Otto-von-Guericke-University Magdeburg. The objective of this study was to examine the morbidity and mortality rates secondary to sleeve gastrectomy (SG) in Germany since 2006. METHODS: Data collection occurred prospectively in an online data bank. All primary bariatric procedures performed were recorded as were all re-operations in patients that had already undergone a primary operation. Specific data compiled on the sleeve gastrectomy procedure were evaluated with a focus on operative details and complication rates. RESULTS: The total study cohort contains 3,122 patients. From January 2006 to December 2007, 144 sleeve gastrectomy procedures were performed in the 17 hospitals participating in the study. The mean body mass index (BMI) of all patients was 48.8 kg/m(2). The BMI of patients undergoing SG was 54.5 kg/m(2). In total, 73.8% of the patients were female and 26.2% of the patients were male. There were no significant differences between patients undergoing SG. The general complication rate after SG was 14.1%, and the surgical complication rate was 9.4%. The postoperative mortality rate was 1.4%. CONCLUSIONS: The complication rate during the first 2 years after SG in Germany is similar to that published in the literature. In order to improve the quality of bariatric surgery, an evaluation of data from a German multicenter trial is necessary to evaluate the position of SG in the bariatric algorithm.

Evidence of thromboembolism prophylaxis in bariatric surgery-results of a quality assurance trial in bariatric surgery in Germany from 2005 to 2007 and review of the literature.

BACKGROUND: Since January 1st, 2005, the current situation for bariatric surgery has been examined by means of a voluntary quality assurance study in Germany with a multicenter design in which 38 hospitals and surgical departments participated. The data are registered in cooperation with the Institute of Quality Assurance in Surgery at the Otto-von-Guericke University of Magdeburg (Germany). METHODS: Data describing peri-interventional characteristics were prospectively documented in an internet online data registry. All primary bariatric procedures performed since January 1st, 2005, were registered. In addition, reoperations in patients who had previously undergone primary surgical intervention were included. As a representative excerpt from the overall prospective multicenter observational study on obesity surgery, data on the type, regimen, and time course of deep venous thrombosis (DVT) prophylaxis were documented. From the number and spectrum of complications, the incidences of clinically manifest DVT or pulmonary embolism (PE) were derived during the in-hospital course and follow-up in conjunction with the type of surgical procedure and body mass index (BMI). RESULTS: Overall, 3,122 bariatric procedures were performed at 38 German hospitals between January 2005 and December 2007. These procedures were subdivided into 2,869 primary operations and 253 revisions (sex ratio, male to female = 25.6:74.4%). The average BMI of all patients was 48.5 kg/m(2) in 2005, 48.4 kg/m(2) in 2006, and 48.0 kg/m(2) in 2007. In 2005 and 2006, gastric banding (GB) was the most commonly performed operation, followed by Roux-en-Y gastric bypass (RYGBP). In 2007, RYGBP was carried out in 42.1% of all bariatric procedures. Interestingly, the incidence of deep venous thrombosis (DVT) was only 0.06%, whereas PE occurred in 0.06% of patients only after hospital discharge. The DVT prophylaxis protocol used has been changed for the last 2 years: the majority of patients with a BMI above 50 kg/m(2) received low-molecular-weight heparin twice a day. CONCLUSION: In Germany, a trend from GB to sleeve gastrectomy (SG) and malabsorptive approach has been evaluated. This trend is associated with differences of the DVT prophylaxis regimen in the profile of bariatric surgical patients depending on BMI and the type of bariatric procedure. Despite the low incidence of DVT and pulmonary embolism (PE) detected, there is a lack of evidence on a reasonable regimen for sufficient DVT prophylaxis in bariatric surgery; instead, there are only recommendations from the guidelines and statements of a specific medical society. Therefore, prospective studies are necessary to determine the optimal DVT prophylaxis for bariatric surgical patients as well as obese patients undergoing surgery.

Separating normosmic and anosmic patients based on entropy evaluation of olfactory event-related potentials.

OBJECTIVE: Methods based on electroencephalography (EEG) are used to evaluate brain responses to odors which is challenging due to the relatively low signal-to-noise ratio. This is especially difficult in patients with olfactory loss. In the present study, we aim to establish a method to separate functionally anosmic and normosmic individuals by means of recordings of olfactory event-related potentials (OERP) using an automated tool. Therefore, Shannon entropy was adopted to examine the complexity of the averaged electrophysiological responses. METHODS: A total of 102 participants received 60 rose-like odorous stimuli at an inter-stimulus interval of 10 s. Olfactory-related brain activity was investigated within three time-windows of equal length; pre-, during-, and post-stimulus. RESULTS: Based on entropy analysis, patients were correctly diagnosed for anosmia with a 75% success rate. CONCLUSION: This novel approach can be expected to help clinicians to identify patients with anosmia or patients with early symptoms of neurodegenerative disorders. SIGNIFICANCE: There is no automated diagnostic tool for anosmic and normosmic patients using OERP. However, detectability of OERP in patients with functional anosmia has been reported to be in the range of 50%.

Early transition metal-catalyzed C-H alkylation: hydroaminoalkylation for Csp3-Csp3 bond formation in the synthesis of selectively substituted amines.

Hydroaminoalkylation is a 100% atom economic method for forming Csp3-Csp3 bonds through C-H activation α to an amine and subsequent reaction with an alkene. When catalyzed by early transition metals, this reaction allows for alternative disconnections for the synthesis of structurally complex amines. This method avoids the installation of protecting groups or directing groups and does not require added oxidants, or photoredox catalysts. In this feature article, we discuss the various selectively substituted amines that can be accessed by hydroaminoalkylation, with a special focus on the development of early transition metal catalysts for their rapid, step and atom efficient assembly.

Supportive and nonsupportive family behaviors: relationships to adherence and metabolic control in persons with type I diabetes.

The Diabetes Family Behavior Checklist (DFBC) was administered to 54 adults and 18 adolescents (less than 19 yr of age) with insulin-dependent diabetes mellitus (IDDM). Subjects and family members completed parallel forms of the DFBC at initial and 6-mo follow-up home interviews. During each of these periods, adherence was assessed via self-report, 1 wk of self-monitoring, and 24-h dietary recalls. The results showed reliable differences between adolescents and adults. More negative interactions with family members were reported by adolescents and their family members, and adolescents were in poorer metabolic control. For adults but not adolescents, negative DFBC scores were prospectively predictive of poorer regimen adherence over the 6-mo interval for measures of glucose testing, insulin injection, and dietary adherence. In addition, higher negative DFBC scores for adults were marginally associated with higher HbA1 levels (P less than 0.10). We conclude that the DFBC is a promising measure of family interaction related specifically to the IDDM regimen and that, for adults, higher levels of nonsupportive family behaviors may be related to reduced regimen adherence and poor control.

Adherence to IDDM regimens: relationship to psychosocial variables and metabolic control.

Thirty-four adolescents (ages 12-14 yr) with IDDM completed a questionnaire assessing regimen adherence over the previous week and psychosocial measures potentially related to adherence. Four aspects of the IDDM regimen were studied: insulin injections, dietary patterns, glucose testing, and exercise. Psychosocial variables included (1) Social Learning Theory measures of diabetes-specific family behaviors and barriers to adherence and (2) more general measures of family interaction. Glycosylated hemoglobin levels were predicted accurately (R = 0.68) from a combination of three adherence measures. The psychosocial measures were not directly related to metabolic control, but they were associated with adherence. Degree of adherence to one aspect of the IDDM regimen was not related to adherence to other aspects of the regimen and different psychosocial variables predicted adherence to different regimen components. The diabetes-specific measures were generally more predictive of adherence than were the more global measures. Implications and limitations of this cross-sectional, correlational study were discussed.

Abnormalities in epidermal lipid metabolism in patients with atopic dermatitis.

Atopic dermatitis is an inflammatory skin disease characterized by dryness and itch of the skin. In this study, we measured the phospholipid content and the fatty acid pattern of lesional and lesion-free epidermal keratome biopsies on 15 patients. For comparison, epidermal biopsies were obtained from healthy individuals undergoing plastic surgery. The phospholipid content of atopic epidermis was nearly twice as high as in healthy epidermis. Monounsaturated fatty acids in the phosphoglycerides were significantly increased (p less than 0.001) and n-6 fatty acids were significantly decreased (p less than 0.001) in lesional atopic epidermis compared to lesion-free epidermis. The content of esterified arachidonic acid in phosphatidylcholine from lesional epidermis was only 49% of that found in healthy epidermis (p less than 0.001). The content of free arachidonic acid was 47% higher (p less than 0.05), whereas the content of free long-chain saturated fatty acids was decreased by 29% (p less than 0.01), in lesional compared to lesion-free atopic epidermis. The disease severity, calculated as an arbitrary index, correlated inversely with the n-6 fatty acid content of lesion-free atopic epidermis (r = -0.89, p less than 0.001). Our findings suggest that atopic epidermis is characterized by an increased activity of phospholipase A2 and an incomplete transformation of phospholipids into other lipid classes.

Reduced neutrophil LTB4 release in atopic dermatitis patients despite normal fatty acid composition.

Propositions about an abnormal fatty acid metabolism in atopic dermatitis patients prompted us to compare the phospholipid fatty acid composition and LTB4 release of neutrophils from 15 atopic dermatitis patients, as well as the adipose tissue triglyceride fatty acid composition, to that of 15 healthy controls matched by age, gender, and smoking habits. We found no differences in the tissue fatty acid composition between the two groups. The release of leukotriene B4 from Ca-ionophore-stimulated neutrophils in patients was on the average only 42% (p less than 0.001) of that measured in the control group, despite the very similar arachidonic acid contents of these cells. Our study does not support the assumption of an abnormal fatty acid desaturation in atopic dermatitis patients. Rather, the capacity to release and/or convert arachidonic acid into leukotrienes in neutrophils appears to be affected by this disease.

Subcutaneous adipose-tissue fatty acids and vitamin E in humans: relation to diet and sampling site.

The influence of diet and sampling site on subcutaneous adipose-tissue fatty acid composition and vitamin E content was examined in 20 healthy subjects. A dietary history and adipose-tissue biopsies from the buttock were obtained from 14 individuals. In another six individuals, samples were taken from both waist and buttock. The relative dietary intake of both polyunsaturated and saturated fatty acids correlated with the relative content in adipose tissue (r = 0.6, p = 0.02). Adipose-tissue vitamin E was strongly associated with dietary intake (r = 0.76, p = 0.004). The content of n - 3 (omega-3) fatty acids in adipose tissue was shown to influence adipose-tissue vitamin E negatively. Waist and buttock fat differed (p less than 0.05) with regard to fatty acid composition whereas no systematic variation was seen in the vitamin E content. The use of adipose-tissue biopsies in epidemiologic studies as measures of the habitual relative intake of fatty acids and vitamin E is suggested.

Ab initio study on the molecular structure of trans-1,2-dihydroxy-1,2-dihydro-8-fluoronaphthalene.

The molecular geometries of two conformations (diequatorial and diaxial) of trans-1,2-dihydroxy-1,2-dihydro-8-fluoronaphthalene have been refined the ab initio gradient method at the 4-21G level to determine the effect of fluoro substitution on the conformational and structural properties of naphthalene dihydrodiols. As with trans-1,2-dihydroxy-1,2-dihydronaphthalene, the conformation with diequatorial hydroxyl groups is the most stable. The structural differences for the fluorinated and unfluorinated naphthalene dihydrodiols are discussed and the possible consequences of the structural and conformational trends on the metabolism of dihydrodiols to dihydrodiol epoxides are considered.

Digital light microscopy: prerequisite for optimum contrast enhancement and increase of resolution.

Since the reproducible production of microscope objectives was enabled by the lens calculations of Ernst Abbe in 1872, various attempts have been made to further increase the resolution of light microscopes. Apart from the improvements on the optical side, especially the introduction of fluorescence methods, the use of digital cameras connected to computers have brought us close to the theoretical limits of optical resolution. Due to improved speed and memory capacity of modern computers mathematical methods can be applied to stored three-dimensional (3D) sequences of digital images which, in addition to just contrast and edge enhancement, may result in the case of real 3D deconvolution, even in the visualisation of structures beyond the theoretical limitations of light optical resolution.

Risk of development of gastric carcinoma in patients with pernicious anemia: a population-based study in Rochester, Minnesota.

To determine the long-term risk of the development of gastric cancer among patients with pernicious anemia, we identified the 152 residents of Rochester, Minnesota, who had well-documented pernicious anemia during the 30-year period 1950 through 1979. These patients were subsequently followed up for more than 1,550 person-years of observation. The observed risk of the development of a gastric cancer in this cohort was compared with that expected on the basis of incidence rates of gastric cancer for the local population. We found one case of gastric carcinoma among our 152 patients with pernicious anemia as compared with an expected incidence of 1.02 (relative risk, 1.0; 95% confidence interval, 0.02 through 5.5). We conclude that no strong indication exists for either radiographic or endoscopic surveillance in asymptomatic patients with pernicious anemia.

In vitro and in vivo studies with thymosin in cancer patients.

Thymosin, fraction V, prepared by the method of Goldstein et al., was studied in in vitro lymphocyte cultures with cells obtained from normal subjects and patients with disseminated cancer. Thymosin lowered blastogenic activity in some patients, did not affect it in others, and increased counts in still others. There was a statistically significant depression in baseline (prethymosin) counts from both normals and patients when individuals whose counts increased in the presence of thymosin were compared with other subjects. We conclude that thymosin tended to raise depressed blastogenesis into the normal range without causing supranormal activity or without itself acting as a mitogen or antigen. Eighty-two in vivo courses in thymosin were given to 32 patients. Analysis of the first thymosin courses in these 32 patients shows that immunologic reconstitution occurred in patients with originally depressed T-cell function and numbers, whereas little change was apparent in patients with initially intact tests of T-cell activity. Clinical effects were equivocal; however, no systematic clinical trial was conducted. Toxicity was minimal (four of the 32 patients); in each case, it consisted of inflammation at the injection site. The in vitro and in vivo results of this study suggest that thymosin therapy modulates and partially normalizes T-lymphocyte numbers and function.

The Budd-Chiari syndrome. Medical and surgical management of 30 patients.

A retrospective review of 30 patients with documented Budd-Chiari syndrome disclosed an overall mortality of 57%. Medical treatment alone was associated with an 86% mortality; hepatic failure was the most common cause of death. Mortality was 31% overall for the surgical group, but there were long-term survivors among patients undergoing portacaval shunting. From this series, no single surgical procedure was found to be clearly superior. Surgical treatment with a side-to-side portacaval shunt seems to be the preferred operation when it can be performed. Surgical intervention should proceed soon after the diagnosis is made, lest extension of thrombus occur. Medical therapy most often is ineffective.