Dynamic mass balancing for wastewater treatment data quality control using CUSUM charts.

Mass balancing is a widely used tool for data quality control in wastewater treatment. It can effectively detect systematic errors in data. To overcome the limitations of the mean balancing error as a measure of data quality, a well established method for statistical process control (the CUSUM chart) is adopted for application on the error vector of balancing data. Two examples show how time periods with stable low mass balancing errors can be detected by the method. The detectability of such time periods depends on the variability of the balancing error which is an important measure for the precision of the data.

Metabolic syndrome in Argentinean patients with systemic lupus erythematosus.

The objective was to determine the prevalence of the metabolic syndrome (MS) in patients with systemic lupus erythematosus (SLE) in Argentina, to assess the factors associated to it, and to compare the results with a control group with non-inflammatory disorders. The study included 147 patients with SLE and 119 controls. MS was defined according to criteria by the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) Scientific Statement. Demographic characteristics, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and Systemic Lupus International Collaborating Clinics/ACR Damage Index (SDI) were assessed as well as administration, maximum dose and cumulative dose of prednisone and hydroxychloroquine (HCQ). MS prevalence was 28.6% (CI 95%: 21.4-36.6) in patients with SLE and 16% in controls (P = 0.0019). Patients with SLE presented higher arterial hypertension frequency compared with controls (43 vs 25%, P = 0.007). When comparing lupus patients with MS (n = 41) and without MS (n = 106), no significant differences were observed regarding duration of the disease, SLEDAI or cumulative prednisone dose. Cumulative damage was associated independently with MS (OR 1.98; P = 0.021), whereas HCQ use was found to be protective (OR 0.13; P = 0.015). Patients with lupus presented higher MS prevalence than controls with non-inflammatory disorders, and occurrence of arterial hypertension was also higher. MS was associated with cumulative damage; the use of HCQ showed to be protective against presence of MS.

Post-traumatic stress disorder in women with eating disorders.

OBJECTIVE: The aim of the study was to assess the frequency of co-morbid post-traumatic stress disorders (PTSD) in women with eating disorders (ED). METHOD: 277 women aged 17 to 50 with a current DSM-IV ED were included. 84 were diagnosed with anorexia nervosa (AN), 152 with bulimia nervosa (BN) and 41 with ED not otherwise specified (EDNOS). Structured Clinical Interviews (SCID-I and SCID-II) were performed. RESULTS: Sixty-eight participants (24.5%) reported unwanted sexual experiences (USE). Fifty-two participants (18.8%) reported some form of childhood sexual abuse (CSA). Four participants (1.4%) met the criteria for PTSD according to the Diagnostic and Statistical Manual-IV (DSM-IV). Participants with a history of USE did not differ from those without USE with regard to ED diagnosis, but were diagnosed more often with any Axis I or Axis II disorder. CONCLUSIONS: The prevalence of PTSD in this sample of women with ED was low (1.4%), despite a USE rate of 24.5%.

Distribution of a persistent sodium current across the ventricular wall in guinea pigs.

A tetrodotoxin-sensitive persistent sodium current, I(pNa), was found in guinea pig ventricular myocytes by whole-cell patch clamping. This current was characterized in cells derived from the basal left ventricular subendocardium, midmyocardium, and subepicardium. Midmyocardial cells show a statistically significant (P<0.05) smaller I(pNa) than subendocardial and subepicardial myocytes. There was no significant difference in I(pNa) current density between subepicardial and subendocardial cells. Computer modeling studies support a role of this current in the dispersion of action potential duration across the ventricular wall.

Background inward current in ventricular and atrial cells of the guinea-pig.

Atrial and ventricular myocytes were exposed to Ca(2+)- and K(+)-free solutions containing blockers of gated channel and exchange currents. Replacement of external sodium by large organic cations revealed a background sodium current ib,Na. In atrial cells, the average conductance was 5.0 pS pF-1. In ventricular cells the conductance was 2.3 pS pF-1. Together with previous results, these figures reveal a strong gradient of background current density: sinus > atrium > ventricle. Replacement of sodium with inorganic cations showed that the channel selectivity behaves like an Eisenman group III/IV sequence, in agreement with previous results. The permeability of the channel to TMA was found to be pH dependent, suggesting that protonation of the channel is a factor determining permeation in addition to ionic size. The values of gb,Na obtained from these experiments are very similar to those assumed in computer modelling of cardiac cell electrical activity.

The effects of prenylamine on single ventricular myocytes of guinea-pig.

1. The action of prenylamine, an antianginal drug, was studied in single ventricular guinea-pig myocytes. In concentrations of 10-50 microM, prenylamine significantly (P less than 0.01) shortened action potentials, and significantly (P less than 0.001) reduced the inward calcium current by 29% to 76% (n = 7). This effect was also present in the presence of adrenoceptor-blockade (with phentolamine and propranolol), and was thus not due to indirect changes in endogenous catecholamine action. 2. Prenylamine did not affect the steady state level of current at the end of long pulses, and does therefore not act by changing time-dependent outward currents. Since the resting potential in the unclamped mode is unchanged during gross changes in action potential duration, it is also unlikely that there are any changes in the background, time-independent potassium conductance. 3. It is concluded that prenylamine has a direct effect on cardiac calcium channels, not mediated by adrenoceptor activation.

Nutritional status and psychometric test scores in cognitively impaired elders.

In a pilot study, we compared dietary and biochemical status for vitamin B1, B2, B12, and C and folate, iron, and protein in CI and CN elders grouped by MMSE scores. Biochemical evaluation of folate and B12 status was continued beyond the preliminary study. Intakes of all nutrients except folate exceeded 66% of the RDA. There were no significant differences among MMSE groups for dietary intake or biochemical values. Transketolase activity increased with degree of impairment, whereas measures for the other vitamins declined. Low or deficient LAA levels were found in 33% of all elders. Folate and B12 deficiencies, respectively, were found in 11% (12/109) and 4% (10/254) of the population. Very low values for serum B12 (less than 250 pg/ml) existed in 15% (37/254) of the subjects (31 CI; 7 CN). Moderately impaired elders (MMSE = 15-20) who used multivitamin supplements had RBC folate (p less than .003) and serum B12 (p less than .02) levels higher than those of subjects who did not use supplements.

Body composition of patients with Alzheimer's disease.

Low body weight is frequently reported in patients with Alzheimer's disease. We sought to discover why by comparing the body composition of 28 cognitively normal elders and 23 institutionalized individuals with Alzheimer's disease. Body mass index was calculated from standing height and weight. Percentages of lean body mass, body fat, and body water were derived from bioimpedance measurements of resistance and reactance. Skinfold thickness was measured at seven body sites to estimate regional fat distribution. Variables were analyzed by analysis of variance with subjects grouped by cognitive status within gender. Activity level and age were not significant covariates. Both women and men with Alzheimer's disease weighed less than control subjects. Differences in body composition were more pronounced in women with Alzheimer's disease, who had lower body mass index (22.0 +/- 3.0 vs 26.1 +/- 5.1), higher percentage of lean body mass (73.8 +/- 5.1 vs 66.9 +/- 6.5), lower percentage of body fat (26.1 +/- 5.1 vs 33.1 +/- 6.5), and higher percentage of body water (55.8 +/- 5.0 vs 49.3 +/- 6.5) compared with control women. Except for lower body weight, the body composition of men with Alzheimer's disease was not significantly different from that of control men. Patients of both sexes with Alzheimer's disease had less truncal body fat compared with controls, which gave them a youthful body habitus. These differences were not accounted for by age, diet, or activity. Our findings indicate that patients with Alzheimer's disease have lower body weight and may require higher energy intake than cognitively normal elders.

Nutritional status of patients with Alzheimer's disease: a 1-year study.

OBJECTIVE: To describe the effects of activity level and energy intake over time on the body weight of patients with Alzheimer's disease compared with cognitively normal subjects. DESIGN: Repeated measures, case-control design with measurements taken at quarterly intervals for 12 months. Subjects were grouped by gender and activity level (sedentary or active) within cognitive status. SETTING: The Alzheimer's disease Special Care Unit, The Clinical Research Center at University of California, San Diego, and the Fred Kasch Exercise Physiology Laboratories at San Diego State University. PATIENTS: Seventeen institutionalized subjects with Alzheimer's disease and 23 community-dwelling control subjects successfully completed the 1-year study. MEASUREMENTS: Before admission to the nursing home, the patients with Alzheimer's disease had a formal assessment for dementia, which showed that they met the criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association work group for probable or possible Alzheimer's disease. Control subjects were screened using the Information-Memory-Concentration Mental Status Test and were found to have no cognitive disabilities. Baseline and quarterly measurements included height, weight, bioimpedance for body composition, and activity by accelerometer counts. Dietary intake of energy and protein was determined at baseline and at 6 and 12 months. RESULTS: Patients with Alzheimer's disease had a significantly higher energy intake than patients in the control group. Both women and men with Alzheimer's disease maintained their weight. Women with Alzheimer's disease had higher percentage of fat-free mass than the control group, but there were no differences in body composition between the groups of men. CONCLUSION: Subjects with Alzheimer's disease can maintain their weight if they are given a diet with adequate energy (35 kcal/kg of body weight).

Nutritional status of free-living Alzheimer's patients.

Self-reported, dietary intake and biochemical estimates of thiamine, riboflavin, folate, vitamin B-12, protein, and iron were compared in 22, free-living elders by individuals who had senile dementia of the Alzheimer's type (SDAT) and in 41 who were cognitively normal (CN). The two groups did not differ significantly in their intake of these nutrients or the number of deficiency states for intake (less than 67% RDA). Low serum transketolase (thiamin; p less than 0.055), red blood cell (RBC) folate (p less than 0.06), and serum vitamin B-12 (p less than 0.05) levels occurred more often in SDAT patients than in CN subjects. Individuals in both groups who used multivitamin supplements had significantly higher biochemical values for thiamine (p less than 0.03), riboflavin (p less than 0.01), and vitamin B-12 (p less than 0.003) than nonsupplement users. Because of the differences in vitamin B-12 and RBC folate levels between groups, a retrospective analysis was performed on a larger group of subjects drawn from a geriatric assessment clinic. Patients with SDAT had significantly lower serum vitamin B-12 (p less than 0.01) and lower RBC folate (p less than 0.03) values than CN subjects. Which mean values for vitamin B-12 and RBC folate were grouped by degree of impairment in SDAT subjects, vitamin B-12 was significantly lower in mildly and moderately impaired subjects than in those with normal cognition. Mean values for both nutrients did not differ significantly between severely impaired and CN subjects. There was a significant quadratic relationship between cognitive impairment and biochemical values for vitamin B-12.(ABSTRACT TRUNCATED AT 250 WORDS)

Local and systemic tolerability of magnesium sulphate for tocolysis.

An open-label, randomised, parallel-group, study was conducted in three study centres in women with premature labor and indication for a single agent intravenous tocolysis therapy with magnesium sulphate. The aim of this study was to examine the local and general tolerability and side-effects of magnesium sulphate for tocolysis. Furthermore, we tested the tolerability of a ready-for-use magnesium solution. No measurements of efficacy were performed during this study. Initially, patients received a loading dose of 4.0 g magnesium sulphate administered over 30 min. Thereafter, a continuous intravenous infusion of 1-2 g magnesium sulphate per hour up to 21 days was given. Venous score (Maddox), vital signs, adverse events as well as general tolerability (assessed by investigator and patients) and blood parameters were assessed. We showed good local and systemic tolerability of high dose magnesium sulphate for tocolysis. Only seven patients (15%) were withdrawn from the study prematurely due to minor adverse events. Potential serious complications of MgSO(4) such as respiratory arrest or clinically relevant respiratory depression were not observed. The most frequently reported local adverse events were injection site pain, itching, erythema, swelling, induration and palpable venous cord. The most common systemic adverse events considered to be possibly related to the study drugs involved the nervous system (dizziness) followed by the digestive system (nausea, constipation). Systolic and diastolic blood pressure changed only slightly during the treatment. Respiratory rate and body temperature remained stable also. Toxic magnesium levels (>2.5 mmol/l) were not observed. The assessment of the clinical investigators with regard to tolerability was very good or good in 72.5% of the patients. The introduction of the ready-to-use solution has the advantage of eliminating the need to mix the solution prior to administration. This means a lower risk of overdose and contamination.

Structural redundancy of data from wastewater treatment systems. Determination of individual balance equations.

Although data reconciliation is intensely applied in process engineering, almost none of its powerful methods are employed for validation of operational data from wastewater treatment plants. This is partly due to some prerequisites that are difficult to meet including steady state, known variances of process variables and absence of gross errors. However, an algorithm can be derived from the classical approaches to data reconciliation that allows to find a comprehensive set of equations describing redundancy in the data when measured and unmeasured variables (flows and concentrations) are defined. This is a precondition for methods of data validation based on individual mass balances such as CUSUM charts. The procedure can also be applied to verify the necessity of existing or additional measurements with respect to the improvement of the data's redundancy. Results are given for a large wastewater treatment plant. The introduction aims at establishing a link between methods known from data reconciliation in process engineering and their application in wastewater treatment.

Investigation of gold nanoparticle radiosensitization mechanisms using a free radical scavenger and protons of different energies.

Gold nanoparticles (GNPs) have been shown to sensitize cancer cells to x-ray radiation, particularly at kV energies where photoelectric interactions dominate and the high atomic number of gold makes a large difference to x-ray absorption. Protons have a high cross-section for gold at a large range of relevant clinical energies, and so potentially could be used with GNPs for increased therapeutic effect.Here, we investigate the contribution of secondary electron emission to cancer cell radiosensitization and investigate how this parameter is affected by proton energy and a free radical scavenger. We simulate the emission from a realistic cell phantom containing GNPs after traversal by protons and x-rays with different energies. We find that with a range of proton energies (1-250 MeV) there is a small increase in secondaries compared to a much larger increase with x-rays. Secondary electrons are known to produce toxic free radicals. Using a cancer cell line in vitro we find that a free radical scavenger has no protective effect on cells containing GNPs irradiated with 3 MeV protons, while it does protect against cells irradiated with x-rays. We conclude that GNP generated free radicals are a major cause of radiosensitization and that there is likely to be much less dose enhancement effect with clinical proton beams compared to x-rays.

Estudio multicéntrico de deterioro cognitivo en lupus eritematoso sistémico: ECLES / Multicenter study of cognitive decline in systemic lupus erythematousus: ECLES

Introducción: los pacientes lúpicos presentan un riesgo incrementado de deterioro cognitivo (DC) comparado con individuos sanos, el cual puede ser debido a múltiples causas. Objetivo: Describir la frecuencia y características del deterioro cognitivo en pacientes con lupus sin manifestaciones neuropsiquiátricas conocidas. Materiales y método: Se incluyeron pacientes de 16 a 55 años con diagnóstico de LES según criterios del Colegio Americano de Reumatología (ACR) de 1997. Se incluyeron test neuropsicológicos acordes a la propuesta del ACR y el cuestionario de Beck para evaluar depresión. Se definió DC a valores de <2 o más desvíos estándar comparada con la media de población normal en al menos un test. Se consideró focal cuando afectó una o más medidas de un dominio y multifocal en 2 o más dominios. Para comparar proporciones se utilizó prueba exacta de Fisher y para comparar variables numéricas se usó prueba de Kruskal-Wallis. Se consideró significativo un valor de p <0,05. Resultados: Se estudiaron 86 pacientes con lupus, el 90% de origen caucásico, 8% mestizos y 1% amerindio. El 82% alcanzó nivel secundario. La frecuencia de DC fue del 65% (56/86). Los dominios afectados: memoria 45%, funciones ejecutivas 30%, atención 29%, lenguaje 4,6%. Se detectó depresión en un 48% de los pacientes. Se analizaron diferentes factores de riesgo, sin hallar diferencias estadísticamente significativas a excepción de la etnia (p=0,02). Conclusión: Se halló una frecuencia elevada de deterioro cognitivo en pacientes con LES, los pacientes no caucásicos tuvieron mayor DC con diferencias significativas en comparación con los pacientes caucásicos.

Background: patients with systemic lupus erythematosus (SLE)have an increased risk of cognitive impairment (CI) compared tohealthy individuals and it may be due to multiple causes. Objective: To determine the frequency and characteristics of CI inlupus patients without known previous neuropsychiatric events. Methods: Patients aged 16 to 55 fulfilling the 1997 ACR criteria forSLE were included. The neuropsychological test battery proposedby the ACR was used to determine CI and Beck depression werealso assessed. CI was defined as values of ≤2 standard deviationscompared to the mean of the general population in at least one test. It was considered focal involvement if it affected one or more measuresof a single domain and multifocal if 2 or more domains wasaffected. To compare proportions, Fisher’s exact test was used andto compare numerical variables, Kruskal-Wallis. A value of p <0.05was considered significant. Results: 86 patients were evaluated, 90% were Caucasian, 8%mestizos and 1% Amerindian. 82% had high school. CI was foundin 65% of patients (56/86). The affected domains were: memory45%, executive functions 30%, attention 29% and language 4.6%. Depression was detected in 48% of patients. Different risk factorswere analyzed and found no statistically significant differences exceptfor ethnicity (p=0.02). Conclusion: A high frequency of CI was found in patients with SLE,non-Caucasian had higher CI with significant differences in comparisonwith Caucasian patients.

Use-dependent reduction and facilitation of Ca2+ current in guinea-pig myocytes.

1. Action potentials, calcium currents (iCa) and cell contraction have been recorded from single guinea-pig myocytes during periods of stimulation from rest. Voltage clamp was carried out using a single microelectrode. Cell contraction was measured optically. All experiments were performed at 18-22 degrees C. 2. An inverse relationship was observed between cell contraction and action potential duration or iCa. Mixed trains of action potentials and voltage clamp pulses preserved this relationship. Long voltage clamp pulses induced negative 'staircases' of iCa and positive 'staircases' of cell contraction. A facilitation of iCa was observed during repetitive stimulation with clamp pulses of 100 ms duration or less and was accompanied by a decrease in cell contraction. 3. The voltage dependence of inward current staircases was found to depend on Ca2+ entry rather than membrane voltage for long voltage clamp pulses and was not affected by 30 mM-TEA or 50 microM-TTX. Current reduction was greatest at 0 mV (P less than 0.05) when iCa was largest. Changes in cell contraction during pulse trains showed a similar voltage dependence. The time constant of current staircases was only mildly voltage dependent. 4. Interference with normal cellular mechanisms for Ca2+ uptake and release by strontium, 1-5 mM-caffeine and 1 microM-ryanodine increased current staircases and could abolish iCa facilitation with short clamp pulses. 5. Variations in the level of Ca2+-dependent inactivation of iCa can explain many features of the changes in iCa during stimulation after rest. Long clamp pulses (or action potentials) may increase cell Ca2+ loading and inhibit iCa. Short clamp pulses reduce available Ca2+ for cell contraction and this may reflect a lowered myoplasmic Ca2+ level which allows facilitation of iCa.

Mechanism of the use dependence of Ca2+ current in guinea-pig myocytes.

1. The mechanism of the use-dependent reduction and facilitation of the calcium current (iCa) in single guinea-pig myocytes described by Fedida, Noble & Spindler (1988) has been examined by varying [Ca2+]o, [Ca2+]i and iCa. 2. Moderate enhancement of [Ca2+]i and [Ca2+]i changes produced by increasing [Ca2+]o reduces iCa and enhances the use-dependent reduction. 3. Intracellular calcium overload, produced by reducing [Na+]o, greatly reduces iCa and almost totally eliminates the use-dependent variations. 4. Use-dependent reduction of iCa is also smaller after substituting external Ba2+ ions for Ca2+ ions. 5. When [Ca2+]i is buffered by intracellular EGTA sufficient to eliminate other [Ca2+]i-dependent processes, such as contraction and Na+-Ca2+ exchange, some use-dependent reduction of iCa remains, although the effect is smaller. Use-dependent facilitation of iCa is more prominent in the presence of internal EGTA. 6. The facilitation of iCa is abolished by Ba2+ replacement of Ca2+ and by the beta-adrenoceptor agonist isoprenaline. This suggests that the facilitation is mediated by Ca2+ entry itself rather than membrane voltage. Facilitation is evident as a delay of current relaxation, even in the presence of internal EGTA.

The control of calcium current reactivation by catecholamines and acetylcholine in single guinea-pig ventricular myocytes.

The time course of reactivation of the calcium current in isolated single cardiac cells is complex. The rising phase is sigmoid and there is an overshoot. Catecholamines increase the initial rate of reactivation but reduce or abolish the overshoot. This combination of effects results in a 'crossover', so that the net effect of adrenaline depends on the pulse interval used. Acetylcholine not only reduces the current amplitude, it also substantially slows recovery. At short intervals the effect of acetylcholine is therefore very large. Agents that increase intracellular cyclic AMP levels affect the amplitude of the current but do not have a large effect on the reactivation time course. It is suggested that the autonomic transmitters exert their effects by controlling the local calcium concentration near the inner surface of the channels. This is supported by the fact that there are natural variations in reactivation time course between different cells and that these are correlated with their calcium loading, as judged by other electrophysiological criteria, such as the speed of calcium current inactivation and the presence of the calcium-dependent slow inward current.