Influence of salt and temperature in the growth of pathogenic free-living amoebae

Introduction

Free-living amoebae are an extensive group of protistans that can be found in a wide variety of environments. Among them, the Acanthamoeba genus and Naegleria fowleri stand out as two of the most pathogenic amoebae and with a higher number of reported cases. N. fowleri is mainly found in warm freshwater water bodies whereas amoebae of the Acanthamoeba genus are broadly distributed through natural and anthropogenic environments. In this regard, the management and the control of the amoebic populations in swimming pools has become a major public health challenge for institutions.

Methods

The aim of this work was to evaluate the growth pattern of trophozoites of A. griffini and N. fowleri at different temperatures and salt concentrations.

Results and discussion

Our results showed that A. griffini resisted a higher concentration of salt than N. fowleri. Moreover, no trophozoites could withstand the salt levels of the sea in in vitro conditions. This work supports the contention that salinity could represent an important and useful tool for the control of the most pathogenic amoebic populations in recreational water bodies.

Diagnostic value of quantitative SPECT/CT in assessing active sacroiliitis in patients with axial spondylarthritis and/or inflammatory low back pain

BACKGROUND

The diagnostic accuracy of bone scintigraphy (BS) increases with SPECT/CT imaging. It would therefore be appropriate to reassess the diagnostic utility of scintigraphy in sacroiliitis with axial spondyloarthritis (SpA). The aim of this study was to compare the diagnostic performance of MRI, SPECT/CT and a combination of both techniques in sacro-iliitis, and to evaluate the correlation between quantitative SPECT/CT indices and quantitative MRI inflammatory lesion scores.

METHODS

Thirty-one patients with active SpA and 22 patients with inflammatory low back pain underwent MRI and SPECT/CT of the sacroiliac joints. The diagnostic accuracy of both techniques was calculated using clinical diagnosis as the gold standard. The correlation between MRI and SPECT/CT was calculated by comparing the SPECT/CT activity indices and the Berlin/SPARCC scoring systems for MRI.

RESULTS

The sensitivity and specificity values in quantitative SPECT/CT, taking the sacroiliac/promontory ratio of >1.36 as the cut-off value, were close to those from MRI published in the literature. The combination of both techniques increased sensitivity while maintaining high specificity. There was a moderate correlation between SPECT/CT and MRI total scores. This correlation was improved by using solely the MRI inflammation scores.

CONCLUSION

Quantitative SPECT/CT showed better diagnostic accuracy than planar scintigraphy and showed a moderate correlation with MRI scores in active sacroiliitis. The combination of both tests increased the diagnostic accuracy. Quanti-tative SPECT/CT could play a relevant role in the diagnosis of active sacroiliitis in patients with high a suspicion of SpA and a negative/inconclusive MRI test or in patients with whom MRI studies cannot be carried out.

Diagnostic accuracy of visual analysis versus dual time-point imaging with 18F-FDG PET/CT for the characterization of indeterminate pulmonary nodules with low uptake

OBJECTIVE

To determine the accuracy of visual analysis and the retention index (RI) with dual-time point ¹⁸F-FDG PET/CT for the characterization of indeterminate pulmonary nodules (IPN) with low FDG uptake.

MATERIALS AND METHODS

A retrospective analysis was performed on 43 patients (28 men, 64 ± 11 years old, range 36-83 years) referred for IPN characterization with ¹⁸F-FDG-PET/CT and maximum standard uptake value ≤ 2.5 at 60 minutes post-injection (SUV_max1). Nodules were analyzed by size, visual score for FDG uptake on standard (OSEM 2,8) and high definition (HD) reconstructions, SUV_max1, SUV_max at 180 minutes post-injection (SUV_max2), and RI was calculated. The definitive diagnosis was based on histopathological confirmation (n = 28) or ≥ 2 years of follow-up.

RESULTS

Twenty-four (56%) nodules were malignant. RI ≥ 10% on standard reconstruction detected 18 nodules that would have been considered negative using the standard SUV_max ≥ 2.5 criterion for malignancy. RI ≥ 10% had a sensitivity, specificity, PPV, NPV and accuracy of 75, 73.7, 78.3, 70, and 74.4%, respectively, while for FDG uptake > liver on HD these were 79.1, 63.2, 73.1, 70.6, and 72.1%, respectively. SUV_max1 ≥ 2, SUV_max2 > 2.5 and FDG uptake > liver on standard reconstruction had a PPV of 100%. FDG uptake > mediastinum on HD had a NPV of 100%.

CONCLUSIONS

RI ≥ 10% was the most accurate criterion for malignancy, followed by FDG uptake > liver on HD reconstruction. On standard reconstruction, SUV_max1 ≥2 was highly predictive of malignancy, as well as SUV_max2 > 2.5 and FDG uptake > liver. FDG uptake < mediastinum on HD was highly predictive of benign nodules.

Model-based methodology for the design of optimal control strategies in MBR plants

This paper proposes a model-based methodology that allows synthesising the most appropriate strategies for optimising the operation of wastewater treatment plants (WWTPs). The methodology is applied with the aim of maximising the nitrogen removal in membrane bioreactors (MBRs). The proposed procedure is based on a systematic approach composed of four steps. First, a sensitivity analysis of the input variables is carried out in order to obtain a first assessment of the potential for operational improvements. Then, the optimum input variable values are calculated by a model-based optimisation algorithm that minimises a cost function associated with the effluent total nitrogen at different temperatures. Then, the optimum operational strategies are identified. Finally, these operational strategies form the conceptual knowledge base for designing automatic control laws. The obtained optimal control strategies have shown a significant improvement in performance in comparison with fixed operation for the studied case, reducing the total nitrogen by 40%.

The Use of Transpyloric Enteral Nutrition in the Critically Ill Child

To assess the use and complications of transpyloric enteral nutrition (TEN) in the critically ill child we evaluated prospectively all children who received TEN in a pediatric intensive care unit (PICU) of a tertiary university hospital. The type of nutrition used, its duration, medication administered, tolerance, gastrointestinal complications (vomiting, abdominal distension or excessive gastric residue, diarrhea, and pulmonary aspiration), nongastrointestinal complications, and mortality were assessed. A comparative analysis was made between the first 2 years of the study and the remaining period. Over a period of 4.5 years, 152 patients between the ages of 3 days and 17 years received TEN for a duration of 19 ± 32.3 days (range 1–240 days). Forty-one patients received TEN during the first 2 years; 100 patients received TEN in the postoperative period after cardiac surgery (66%). One hundred seventeen patients (77%) received sedation and 65 (43%) received muscle relaxants, presenting no extra complications. Twenty-four patients (15.8%) presented with gastrointestinal complications: abdominal distension and/or excessive gastric residue in 17 and diarrhea in 11. Gastrointestinal intolerance was associated with pulmonary infection ( p < 0.05), altered hepatic function ( p < 0.001), and hypokalemia or hypocalcemia ( p < 0.05). Diarrhea was more frequent in patients with shock ( p < 0.05), altered hepatic function ( p < 0.05), excessive gastric residue ( p < 0.001), and hypokalemia or hypocalcemia ( p < 0.05). In the second study period, the number of patients on TEN and the doses of sedatives, muscle relaxants, and vasoactives were higher ( p < 0.05), with no increase in the incidence of complications. TEN is a useful method of nutrition with few complications in the critically ill child.

Analysis of the stability of high-solids anaerobic digestion of agro-industrial waste and sewage sludge

The pilot-scale high-solids anaerobic digestion (HS-AD) of agro-industrial wastes and sewage sludge was analysed in terms of stability by monitoring the most common parameters used to check the performance of anaerobic digesters, i.e. Volatile Fatty Acids (VFA), ammonia nitrogen, pH, alkalinity and methane production. The results reflected similar evolution for the parameters analysed, except for an experiment that presented an unsuccessful start-up. The rest of the experiments ran successfully, although the threshold values proposed in the literature for the detection of an imbalance in wet processes were exceeded, proving the versatility of HS-AD to treat different wastes. The results evidence the need for understanding the dynamics of a high-solids system so as to detect periods of imbalance and to determine inhibitory levels for different compounds formed during anaerobic decomposition. Moreover, the findings presented here could be useful in developing an experimental basis to construct new control strategies for HS-AD.

Tuberculosis diagnosis after bleach processing for early stage tuberculosis laboratory capacity building

The diagnosis of tuberculosis is seriously hampered in the absence of standard biosafety laboratory facilities for specimen concentration and Mycobacterium tuberculosis culture. Within a laboratory twinning arrangement, heat-fixed direct smear and sediment from 74 bleach-processed and 20 non-processed specimens from Cumura Hospital, Guinea-Bissau, were sent to Lisbon for molecular evaluation of rifampicin resistance. Sequence analysis of a 369 base-pair rpoB locus detected 3.2% (3/94) resistant specimens. To our knowledge, this represents the first report on the molecular analysis of M. tuberculosis from bleach-processed sputum, an alternative to current diagnostic practice in low-resource settings.

Water network cost optimization in a paper mill based on a new library of mathematical models

The increasing costs associated with water supply and the disposal of wastewater has stimulated industries to seek more efficient water management systems. Mathematical modelling and simulation can be a very valuable tool for the study of the multiple alternatives available whilst assessing optimum solutions for water management in industry. This study introduces a new steady state model library able to reproduce industrial water circuits. It has been implemented in a novel software framework for the representation, simulation and optimization of industrial water networks. A water circuit representing a paper mill has been modelled and simulated showing the capability to reproduce real case studies. Alternative scenarios for the water network have also been tested to assess the capability of the models to optimize water circuits minimizing total cost.

A knowledge-based control system for air-scour optimisation in membrane bioreactors

Although membrane bioreactors (MBRs) technology is still a growing sector, its progressive implementation all over the world, together with great technical achievements, has allowed it to reach a mature degree, just comparable to other more conventional wastewater treatment technologies. With current energy requirements around 0.6-1.1 kWh/m3 of treated wastewater and investment costs similar to conventional treatment plants, main market niche for MBRs can be areas with very high restrictive discharge limits, where treatment plants have to be compact or where water reuse is necessary. Operational costs are higher than for conventional treatments; consequently there is still a need and possibilities for energy saving and optimisation. This paper presents the development of a knowledge-based decision support system (DSS) for the integrated operation and remote control of the biological and physical (filtration and backwashing or relaxation) processes in MBRs. The core of the DSS is a knowledge-based control module for air-scour consumption automation and energy consumption minimisation.

High prevalence of ST121 in community-associated methicillin-susceptible Staphylococcus aureus lineages responsible for skin and soft tissue infections in Portuguese children

In order to evaluate the incidence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in Portugal, we analyzed a collection of 38 S. aureus isolates recovered from 30 children attending the pediatric emergency department of a central hospital in Lisbon due to skin and soft tissue infections. Molecular characterization identified seven clonal lineages among the 35 methicillin-susceptible S. aureus (MSSA) isolates, of which the major lineage PFGE A/t159/ST121 included 63% of the isolates. The three MRSA isolates belonged to the Pediatric clone PFGE D/t535/ST5-IV (n = 2) and to the European CA-MRSA clone PFGE G/t044/ST80-IVc (n = 1). All isolates harbored several virulence factors, namely, leukocidins. Panton-Valentine leukocidin (PVL) was produced by isolates from five MSSA lineages and by the ST80 MRSA. Of interest, this is the first reported isolation of CA-MRSA ST80 in Portugal.

Knowledge-based system for automatic MBR control

MBR technology is currently challenging traditional wastewater treatment systems and is increasingly selected for WWTP upgrading. MBR systems typically are constructed on a smaller footprint, and provide superior treated water quality. However, the main drawback of MBR technology is that the permeability of membranes declines during filtration due to membrane fouling, which for a large part causes the high aeration requirements of an MBR to counteract this fouling phenomenon. Due to the complex and still unknown mechanisms of membrane fouling it is neither possible to describe clearly its development by means of a deterministic model, nor to control it with a purely mathematical law. Consequently the majority of MBR applications are controlled in an "open-loop" way i.e. with predefined and fixed air scour and filtration/relaxation or backwashing cycles, and scheduled inline or offline chemical cleaning as a preventive measure, without taking into account the real needs of membrane cleaning based on its filtration performance. However, existing theoretical and empirical knowledge about potential cause-effect relations between a number of factors (influent characteristics, biomass characteristics and operational conditions) and MBR operation can be used to build a knowledge-based decision support system (KB-DSS) for the automatic control of MBRs. This KB-DSS contains a knowledge-based control module, which, based on real time comparison of the current permeability trend with "reference trends", aims at optimizing the operation and energy costs and decreasing fouling rates. In practice the automatic control system proposed regulates the set points of the key operational variables controlled in MBR systems (permeate flux, relaxation and backwash times, backwash flows and times, aeration flow rates, chemical cleaning frequency, waste sludge flow rate and recycle flow rates) and identifies its optimal value. This paper describes the concepts and the 3-level architecture of the knowledge-based DSS and details the knowledge-based control module. Preliminary results of the application of the control module to regulate the air flow rate of an MBR working with variable flux demonstrates the usefulness of this approach.

Assessment of the level of sedation in children after cardiac surgery

BACKGROUND

There is no reference method for the evaluation of the level of sedation in children after cardiac surgery. The utility of the bispectral index and middle latency auditory evoked potentials has not been evaluated.

METHODS

The bispectral index, middle latency auditory evoked potentials, Ramsay scale, and COMFORT scale were used for assessment of the level of sedation in critically ill children after cardiac surgery and other surgical procedures. The measurements with these four methods were recorded simultaneously once a day for five days. The level of sedation was categorized in two levels, moderate or deep, according to the values obtained from each method. Correlations and agreements among the methods and the best bispectral index and middle latency auditory evoked potential values that discriminated between the two levels of sedation were calculated.

RESULTS

Thirty-two children after cardiac surgery were included in the study, together with eighteen children after other surgical procedures who formed the control group. In each group, the correlation and agreement between the four methods varied between moderate and good. In the cardiac surgery patients, when the level of sedation was determined by the Ramsay scale, the best values of bispectral index and middle latency auditory evoked potentials that discriminated between the two levels of sedation were 63.5 and 37.5, respectively, and these values predicted the level of sedation correctly in 84.4% of the patients with each method.

CONCLUSIONS

Bispectral index and middle latency auditory evoked potentials could be useful to assess the level of sedation in children after cardiac surgery.

Cardiac output and blood volume parameters using femoral arterial thermodilution

BACKGROUND

The pulse-induced continuous cardiac output (PiCCO) system is a less invasive method than pulmonary thermodilution for the measurement of cardiac output and estimating blood volume parameters. The normal values in children have not been defined. The purpose of the present paper was therefore to evaluate cardiac output and parameters of blood volume using femoral arterial thermodilution in critically ill children.

METHODS

A prospective study was performed in 17 critically ill children aged between 2 months and 14 years. Two measurements were taken for each determination of cardiac output, global end diastolic volume (GEDVI), intrathoracic blood volume index (ITBI), extravascular lung water index (ELWI), systolic volume index (SVI), stroke volume variation (SVV), cardiac function index (CFI), left ventricular contractility (dp/dt max), and the systemic vascular resistance index (SVRI).

RESULTS

One hundred and seventeen measurements were performed. The mean cardiac index (CI) was 3.5 +/- 1.3 L/min per m(2). The GEDVI (399.7 +/- 349.1 mL/m(2)), ITBI (574.5 +/- 212.2 mL/m(2)) and dp/dt max (804.6 +/- 372.1 mmHg/s) were lower than reported in adults, whereas ELWI (18.9 +/- 9.3 mL/m2) and CFI (8 +/- 2.5 L/min) where higher. The GEDVI, SVI, dp/dt max and CI increased with the weight of the patients whereas the ELWI values decreased.

CONCLUSIONS

Femoral arterial thermodilution is a suitable technique for the measurement of cardiac output in critically ill children. The intrathoracic and intracardiac volumes are lower than in adults, whereas extrapulmonary water is higher; these values are related to the weight of the patient.

Responsiveness to stimuli of bispectral index, middle latency auditory evoked potentials and clinical scales in critically ill children

SUMMARY

We performed simultaneous recordings of Bispectral Index (BIS) and middle latency auditory evoked potentials. We also recorded two clinical scales, the Modified Ramsay scale and the COMFORT scale. Heart rate and blood pressure were measured once a day, for a maximum of 5 days, in 81 critically ill children. Changes with tactile, auditory, and painful stimuli were analysed. All the stimuli significantly increased the BIS value, the painful stimulus having the greatest effect. The painful stimulus was the only one that altered the middle latency auditory evoked potentials. Although the responses of the clinical scales to stimuli were statistically significant, they were of little clinical relevance. None of the stimuli used significantly altered the heart rate or blood pressure. We conclude that tactile, auditory and painful stimuli produced changes of little relevance in the clinical scales, BIS or middle latency auditory evoked potentials. We found the BIS was the most sensitive method and the painful stimulus had the greatest effect.

Assessing sedation in critically ill children by bispectral index, auditory-evoked potentials and clinical scales

OBJECTIVE

To evaluate the correlation and agreement between the bispectral index (BIS), middle latency auditory-evoked potential index (AEP index), Ramsay scale (RS) and COMFORT scale (CS) for evaluation of the level of sedation in critically ill children.

DESIGN

Prospective observational study.

SETTING

Pediatric critical care unit.

PATIENTS

Seventy-seven critically ill children receiving sedation and mechanical ventilation.

MEASUREMENTS AND RESULTS

Simultaneous recording of BIS, AEP index, RS and CS were performed once a day, for a maximum of 5 days. Two levels of sedation were categorized: light-moderate versus deep-very deep. Correlations between methods were determined using Spearman rank correlation test and the agreement using Cohen's Kappa test. The correlation and agreement between the four methods was moderate-to-good. Correlation was not found in paralyzed children. There was no correlation between the four methods and the heart rate or blood pressure, or with the type or dose of sedative medication. Receiver-operating characteristic (ROC) analysis revealed best discrimination between light-moderate and deep-very deep sedation at BIS and AEP index values of 63.5 and 33.5 when the level of sedation was classified by the RS, and at BIS and AEP index values of 67 and 37.5, respectively, when the level of sedation was classified by the CS.

CONCLUSION

There is a moderate-to-good correlation and agreement of BIS and AEP index with the clinical scales in critically ill children without neuromuscular blockade. BIS and AEP index could be useful to evaluate the level of sedation in critically ill children with and without neuromuscular blockade.

The effect of operational parameters of the process of sludge ozonation on the solubilisation of organic and nitrogenous compounds

An evaluation of various operational parameters on the process of sludge ozonation was carried out based on semi-batch experiments. Particular reference has been given to examine the main parameters affecting the solubilisation of organic matter and nitrogenous compounds. Various sets of experiments were undertaken using real sewage sludge to feed a semi-industrial ozonation plant. Applying ozone dosages between 25 and 35 mg O(3)/gTSS, the organic matter solubilisation obtained through ozonation increases proportionally to ozone dosage until a maximum value of 430 mg COD/L. Concerning the nitrogenous compounds, no variation in nitrite concentration and a low increase in nitrate concentration were attained, regardless of the applied ozone dosage. Little increase in ammonia concentration was achieved for low ozone dosages, whilst applying dosages higher than 20 mg O(3)/gTSS, the variation of ammonia increased proportionally with ozone dosage. Experiments using hydraulic retention time (HRT) between 10 and 60 min resulted in a similar COD solubilisation, confirming a rapid rate of cell lysis during ozonation of sludge.

Transpyloric enteral feeding in the postoperative of cardiac surgery in children

PURPOSE

The aim of this study is to assess the utility of transpyloric enteral nutrition in the postoperative period of cardiac surgery in children.

METHODS

A prospective, observational study was performed on children receiving transpyloric enteral nutrition in the postoperative period of cardiac surgery. The type of nutrition, duration, tolerance, and complications were studied.

RESULTS

Children (212) between the ages of 3 days and 17 years received transpyloric enteral nutrition in the postoperative period of cardiac surgery. The duration of the transpyloric feeding was 16 +/- 23.8 days, and the maximum calorie delivery was 85.1 +/- 25.7 kcal/kg/d. Tolerance to nutrition was good and was not affected by the infusion of vasoactive drugs, sedatives, or muscle relaxants. Of the study population, 14.6% presented with gastrointestinal complications, 9.4% with abdominal distension and/or excessive gastric residue, and 7.5% with diarrhea. Nutrition was withdrawn in 2.4% of the patients because of gastrointestinal complications. Mortality was not related to any characteristic of the nutrition or to gastrointestinal complications.

CONCLUSIONS

Transpyloric enteral nutrition is useful and is a simple feeding method that enables a high calorie delivery to be provided with few complications in the postoperative period of cardiac surgery in children, including those receiving high doses of sedatives and muscle relaxants.

Severe ischemia of the lower limb and of the intestine associated with systemic vasoconstrictor therapy and femoral arterial catheterization

OBJECTIVE

To report a case of peripheral and intestinal ischemia associated with arterial catheterization and terlipressin treatment in a child.

DESIGN

Case report.

SETTING

Pediatric intensive care unit of a university hospital.

PATIENT

The patient was a 2-month-old female infant with shock refractory to treatment with catecholamines, who received treatment with terlipressin (20 microg/kg/4 hrs). In order to monitor her cardiac output, the right femoral artery was catheterized with a 4-Fr PiCCO catheter. At 60 hrs, the patient presented progressive ischemia of the right lower limb and intestinal ischemia. The ischemia did not improve despite withdrawal of the catheter and interruption of the terlipressin administration; it progressed to massive intestinal ischemia, and the patient died.

CONCLUSIONS

Arterial catheterization combined with the administration of vasoconstrictor drugs, particularly vasopressin or terlipressin, can lead to local ischemic complications and severe intestinal ischemia in infants in shock.

Mass and charge conservation check in dynamic models: application to the new ADM1 model

This paper proposes a systematic methodology for the analysis of the mass and charge balances in dynamic models expressed using the Petersen matrix notation. This methodology is based on the definition of the model components via elemental mass fractions and in the estimation of the COD as a function of the redox equations associated with these elements. This approach makes the automatic calculation of all the stoichiometric coefficients under different measuring units and the study of COD, charge or mass fluxes easier. As an example of its application this methodology was applied to the ADM1 in order to illustrate its usefulness for the analysis of organic matter characterisation, nitrogen release or biogas composition in anaerobic digestion. The application of the methodology for a rigorous integration of different IWA models is proposed for further study.

Different Proinflammatory Cytokine Serum Pattern in Neonate Patients Undergoing Open Heart Surgery. Relevance of IL-8

The purpose of this work was to investigate the clinical significance of serum levels of proinflammatory cytokines in pediatric patients undergoing cardiopulmonary bypass. We divided the patients in two groups: 8 neonates, and 19 non-newborn children. IL-1beta, IL-6, IL-8, and TNF serum levels were quantified before sternotomy, at admission to the PICU (30 min postoperatively), 24 h after the onset of surgery and 3 days after the operation. Surgical cardiac stress elicits significant increments of IL-6, IL-8 and TNF serum concentrations in both neonates and non-neonates, regardless of their preoperative clinical condition. However, in newborns the magnitude of the proinflammatory cytokine increments was, in particular with IL-8, remarkably greater than in older children. Moreover, neonate and non-neonate patients showed clearly disparate patterns of serum concentrations over time of both IL-8 and TNF. There was a marked relationship between IL-8 levels and postoperative morbidity, evaluated by pulmonary dysfunction, days on inotropic support and days of PICU stay in both neonates and non-neonates patients. In contrast, we found no relationship between serum levels of IL-6 and TNF and postoperative clinical data. Newborn and non-newborn patients undergoing cardiopulmonary bypass exhibit dissimilar patterns of proinflammatory cytokines. IL-8 might be implicated in the multiorganic dysfunction related to cardiopulmonary bypass in pediatric patients.

Characteristics of the gluteus medius muscle in an asymptomatic patient with radiographic signs of coxarthrosis

This case study describes the micromorphology and some biochemical features of gluteus medius muscle in a 79-year-old woman with radiographic signs of coxarthrosis but with no clinical symptoms who initially was admitted in the orthopaedic emergency service with a non-displaced subcapital fracture of the femoral neck due to a domestic accident (fall). The X-ray of the hip showed some characteristic features of coxarthrosis, classified grade 2 of the Kellgren criteria. After informed consent, it was decided to carry out the functional evaluation according to the indexes of Lequesne and WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) and to take a biopsy of the gluteus medius muscle for microscopical examination and myosin heavy chain isoform identification during hip replacement surgery. For the Lequesne Index (score 0-24), the total score was 0, and for the WOMAC (score 0-96), the total score was also 0, both speaking in favour of full joint and muscle function. All the structural features observed in muscle were considered not to have any pathological relevance. The composition of the myosin heavy chains in the gluteus medius muscle was 48% MHC I, 41% MHC IIa, and 11% MHC IIx. The muscle characteristics do not support earlier concepts about muscle weakness as a predisposing factor for osteoarthritis. It is moreover concluded that the diagnosis should rather consider clinical symptoms than radiographic signs of osteoarthritis.

Eating attitudes and the use of alcohol, tobacco, and exercise among male and female adolescents

OBJECTIVES

To determine the differences between male and female adolescents in the associations of disturbed eating attitudes with the use of smoking, alcohol, and exercise.

METHOD

Nonclinical adolescents-174 males and 157 females-completed the Eating Disorders Inventory (EDI) and a measure of engagement in the use of smoking, alcohol, and exercise. An analysis of variance (ANOVA) was used to determine the impact of Gender x Use of the behaviour upon eating and related attitudes.

RESULTS

Gender and use of smoking and alcohol were each related to eating attitudes. However, in the case of exercise, there were strong interactions of the behaviour and gender. Women who exercised regularly had higher levels of restriction, body dissatisfaction, and interoceptive awareness, whereas men did not.

CONCLUSIONS

It appears that men and women exercise for different reasons, in relation to their eating and related attitudes. It is possible that men exercise for positive goals (e.g., fitness), whereas women exercise to escape perceived negative consequences (e.g., weight gain). This is not the case for alcohol and tobacco use. These findings are discussed, and further research is proposed.

Newborn patients exhibit an unusual pattern of interleukin 10 and interferon gamma serum levels in response to cardiac surgery

OBJECTIVE

The aim of this study was to determine the clinical significance of serum levels of interleukin 10 and interferon gamma in pediatric patients undergoing cardiopulmonary bypass.

METHODS

We divided the patients into 2 groups: 8 neonates and 19 non-newborn children. Interleukin 10 and interferon gamma serum levels were quantified before sternotomy, at admission to the pediatric intensive care unit (30 minutes postoperatively), 24 hours after the onset of the operation, and 3 days after the operation.

RESULTS

Newborn patients displayed significantly greater amounts of serum interleukin 10 than older children, not only in regard to the peak level achieved but also at every postoperative time point analyzed. In contrast, no significant changes in interferon gamma serum levels were observed in neonates at any time point, whereas non-newborn pediatric patients showed a significant increase in interferon gamma serum concentrations immediately after the operation. This unusual pattern of cytokine response in newborn patients was not associated with modifications in cortisol serum levels. Furthermore, although neonates had significantly different surgical and clinical variables than did the non-newborn pediatric patients, the variation in interleukin 10 production in neonates could not be accounted for by differences in the magnitude of surgical injury. In the group of neonates, there were significant positive correlations between peak interleukin 10 serum levels and both partial pressure of arterial oxygen/fraction of inspired oxygen ratio and postoperative body weight gain.

CONCLUSIONS

Newborn patients undergoing cardiopulmonary bypass exhibit a distinctive biologic response pattern characterized by high levels of serum interleukin 10 without changes in serum interferon gamma. This cytokine imbalance could have potential clinical implications.

Relationships between objective physical characteristics and the use of weight control methods in adolescence: a mediating role for eating attitudes?

This study of non-clinical adolescent males and females examined associations of objectively measured physical characteristics with greater use of methods of weight control and considered whether the relationships between these variables might be explained by a mediating effect of a subjective characteristic--unhealthy eating attitudes. Non-clinical male and female adolescents completed measures of weight control and eating attitudes, and their physical characteristics were measured using a range of standardized anthropometry techniques. Regression analyses were used to test the role of eating attitudes as mediators in the relationship between physical characteristics and the use of weight control methods. The data were compatible with a partial mediator model, where physical characteristics influence eating attitudes, and those where attitudes drive the use of methods to control weight. However, not all of the relationship was explained by this mediator. In addition, there were different patterns of association for men and women, consistent with different patterns of bodily focus between the genders. These findings stress the importance of understanding objective physical characteristics as well as subjective eating attitudes to find out why people use different levels of weight control behaviours. Limitations, further research and potential implications for clinical and preventative programmes are discussed.

Hepatic dysfunction after cardiac surgery in children

OBJECTIVE: The objective of this study was to analyze the incidence and significance of hepatic dysfunction after cardiac surgery in children. DESIGN: Prospective, observational study. SETTING: Pediatric intensive care unit of a university hospital. PATIENTS: The study consisted of 232 children ranging in age from newborn to 17 years with no history of liver disease. MEASUREMENTS AND MAIN RESULTS: Aspartate aminotransferase (AST), alanine aminotransferase (ALT), gammaglutamyltranspeptidase (GGT), alkaline phosphatase, total and conjugated bilirubin, blood glucose, urea, creatinine, and coagulation studies were determined at admission, at 24 and 48 hrs, and at 7 days. Hepatic dysfunction was taken as an ALT of > 100 IU/L or a moderate or high hepatic score. The statistical study included bivariate analysis and multivariate logistic regression to study the risk factors for hepatic dysfunction. Twenty-one patients (9%) showed an ALT > 100 IU/L, and 29.3% had a moderate or high hepatic score. A relationship was found between hepatic dysfunction and the type of cardiopathy (D-transposition of the great arteries and coarctation of the aorta), shock, the administration of dopamine or epinephrine, renal insufficiency, the presence of pulmonary changes (pulmonary edema, atelectasis, pulmonary hypertension, hypoxemia), hematologic disturbances (prothrombin time, kaolin-cephalin time, fibrinogen, and platelets), and the need for a greater number of transfusions of packed cells, plasma, and platelets. Compared with 7.6% of the rest of the patients (p <.001), 38% of patients with an ALT > 100 IU/L died. The hepatic score of those patients who died was 4.2 (2.3)-higher than that of the survivors at 1.5 (1.8), (p <.001). Shock and renal insufficiency were the factors most significantly related to the development of hepatic dysfunction. CONCLUSIONS: Hepatic dysfunction is an uncommon complication in children after cardiac surgery. This complication is related mainly to hemodynamic disturbances and renal insufficiency and is an indicator of poor prognosis.

Study of paediatric intensive care units in Spain. Spanish Society of Paediatric Intensive Care

OBJECTIVE

To describe the organisation of paediatric intensive care units in Spain and the medical assistance provided during 1996.

METHODS

A written questionnaire was sent to all the paediatric ICUs linked to or within the Spanish public health system.

RESULTS

Thirty-one of the 34 paediatric ICUs replied. All are medico-surgical units. Eighteen treat only paediatric patients, 12 paediatric and neonatal patients, and one paediatric and adult patients. Fifteen units have fewer than seven beds, eight have between 7 and 12 beds, and eight between 13 and 18 beds. Of the paediatric ICUs, 83.8 % are staffed by paediatricians specialised in paediatric intensive care. The mean number of on-call on site periods of duty for each member of the medical staff was 5.1 +/- 1.7 per month. Thirty of the 31 units undertake paediatric resident training, 13 train residents specialising in paediatric intensive care and 12 participate in medical student training. In 1996 there were 9,585 admissions (309 +/- 182 patients per ICU) signifying 35.3 +/- 14 patients/bed. Of the patients, 65.9 % were medical and 34.1 % surgical. The mean duration of stay was 5.6 +/- 2.1 days. The mortality rate was 5.4 +/- 3.2 %. The main causes of death were multiple organ failure and brain death.

CONCLUSIONS

In Spain, paediatric intensive care is principally performed by specialised paediatricians. Although the general results for 1996 are similar to those of other European countries, efficiency studies are necessary to plan and re-organise the paediatric intensive care units in Spain.

Transpyloric enteral feeding in critically ill children

BACKGROUND

Nutrition is important in childhood because the child has a lower energy reserve than the adult and a higher demand for calories because of ongoing growth. In this study, the utility of transpyloric enteral feeding (TEF) in critically ill children was evaluated.

METHODS

A prospective, descriptive study was made in a pediatric intensive care unit of a tertiary pediatric center of 41 critically ill children, 30 after surgical procedures and 11 with nonsurgical illness, aged 8 days to 12 years, who received transpyloric enteral feeding with 8- or 10-Fr weighted feeding tubes. Analysis was made of tolerance and complications (vomiting, abdominal distension, excessive gastric residual, diarrhea, and pulmonary aspiration) of TEF.

RESULTS

The mean duration of TEF was 19.5 +/- 26.8 days (range, 1-120 days). The administration of sedative agents or inotropic drugs did not alter toleration of TEF. Eight of 12 patients treated with continuous infusion of vecuronium tolerated TEF without complications. Eleven gastrointestinal complications occurred in 10 patients, abdominal distension and excessive gastric residual in 7 (17%), and diarrhea in 4 (9.7%). In 7 patients gastrointestinal complications improved, with decreasing use or transitory interruption of TEF, but in 4 patients (9.7%), TEF had to be withdrawn. Gastrointestinal complications were more frequent in postsurgical than in nonsurgical patients (p < 0.001). No patients suffered from pulmonary aspiration, and the incidence of pulmonary infection and hepatic dysfunction diminished during TEF.

CONCLUSIONS

Transpyloric enteral feeding is a good method of nutritional support in critically ill children and can be used in patients treated with neuromuscular blocking agents. The frequency and severity of complications and the risks of pulmonary infection and hepatic dysfunction related to TEF are low.

Bronchoesophageal fistula secondary to aspiration of tongue adhesion button in a child with glossoptosis

A newborn boy with obstructive apnea secondary to glossoptosis was treated by securing his tongue to his lower lip. Soon after, the button that served for posterior fixation became detached and was thought to have been evacuated via the digestive tract. Twenty-two months later the infant presented with pneumonia involving the right lower lobe and hemoptysis, causing an acute respiratory distress syndrome (ARDS). After mechanical ventilation was started marked gastric distention was observed. Esophagography and bronchography revealed a fistula between the right main stem bronchus and the esophagus. During surgical repair the plastic fixation button was found in the bronchial orifice of the fistula. Despite surgical correction of the fistula the child died of refractory respiratory failure.

Pediatric basic and advanced life support courses: first experience in Spain

OBJECTIVE

to evaluate the efficiency of the first experience in pediatric basic and advanced life support courses in Spain.

MATERIAL AND METHODS

we have given two pediatric basic life support (PBLS) courses of 8 h each to 52 school teachers and ambulance drivers, and 10 30-h pediatric advanced life support (PALS) courses to 276 health professionals, 62 nurses and 214 physicians (80 pediatricians, 57 pediatric, anesthesiology and intensive care medicine residents, 10 general physicians and 52 emergency physicians). We developed the courses according to the guidelines for pediatric life support from the European Resuscitation Council. We performed an initial and final theoretical written test, continuous practical evaluation and a written survey about the quality of the course.

RESULTS

on PBLS courses, only 12% of practitioners answered at least 80% of the questions in the initial theory test correctly, compared with 77% in the final test (P < 0.001). All the students acquired skills in basic pediatric resuscitation. In the PALS courses, only 30% of practitioners answered at least 75% of the questions in the initial test correctly (35% of physicians and 12% of nurses, P < 0.01); this percentage increased to 95.6% in the final test (96% of physicians and 93.5% of nurses, P < 0.05). Of students, 95% acquired skills in advanced pediatric resuscitation. All students and teachers considered the theoretical and practical formation received adequate.

CONCLUSIONS

basic and advanced pediatric life support courses are a useful educational method for the general population, health professionals, physicians and nurses in theoretical and practical pediatric resuscitation.

Two different maturational stages of natural killer lymphocytes in human newborn infants

The objective of this study was to assess the basis for the diminished natural killer (NK) lymphocyte activity of neonates. We found either severely reduced (63% of 68 neonates) or normal (similar to healthy adult) levels of NK activity. The percentages of cord blood mononuclear cells from the two groups of infants that expressed CD16, a differentiation antigen found in NK cells, were similar and within the range found in peripheral blood mononuclear cells of adults. However, infants with low NK activity had reduced numbers of cells in the CD16+56+ subpopulation, whereas the number of these effector cells present in cord blood mononuclear cells from infants with normal NK activity was within the range found in adults. Recombinant interleukin-2, but not recombinant interferon-gamma, normalized the low NK activity of infants in a dose- and time-dependent manner. Analysis of the pattern of target cell susceptibility to lysis, together with the CD16+CD3- phenotype of the precursor and effector lymphocytes, demonstrated that the induced cytotoxicity was mediated by NK cells. In contrast, NK cells from infants with normal cytotoxic levels exhibited a functional response to interleukin-2 and interferon-gamma similar to that of adults. Our results indicate that NK cells in human neonates go through two different maturational stages.