Process efficiency in relation to enzyme pre-treatment duration in black soldier fly larvae composting

Black soldier fly larvae (BSFL) composting is a treatment in which biodegradable food waste is converted into animal-feed protein and organic fertiliser. BSFL composting has greatest potential for mixed food waste, but under European Union regulations only plant-based waste is permitted as feed for larvae. Biomass conversion efficiency (BCE) in BSFL composting is lower for plant-based waste than for mixed food waste. One way of improving BCE for plant-based waste is to add enzymes to make the waste more available to the larvae, but enzyme pre-treatment is not commonly applied prior to BSFL composting. Therefore this study examined the impact of enzyme pre-treatment duration on process efficiency in BSFL composting of lettuce-cabbage waste pre-treated with enzymes for 0-4 days. The results showed that total solids (TS) in larvae decreased with longer enzyme pre-treatment. Direct addition of enzymes at the start of BSFL treatment (0 day pre-treatment) resulted in 22% higher BCE on a volatile solids (VS) basis compared with the control, while longer pre-treatment did not improve BCE further. Much of the VS was respired in the 0-day pre-treatment, resulting in lower mass of residues at the end of treatment. Longer pre-treatment increased microbial respiration, suggesting that the microbial community consumed more easily available carbohydrates during the pre-treatment step, which counteracted the purpose of enzyme pre-treatment, i.e. increasing BCE during BSFL composting.

Socio-economic determinants of vitamin A intake in children under 5 years of age: evidence from Pakistan

BACKGROUND

Vitamin A deficiency, which is a leading health issue worldwide, is estimated to affect approximately 190 million children globally. The most affected areas are Africa and parts of Southeast Asia.

METHODS

The present study examined the use of vitamin A supplementation and the association between socio-demographic factors and vitamin A supplementation in children aged less than 5 years from a cross-sectional demographic survey of Pakistan. Odds ratios were used to express the association between the independent and dependent variables.

RESULTS

For 10 906 children, the coverage of vitamin A supplementation was 68.5%, with regional variations of between 8% and 79%. A multiple logistic regression analysis was used on a nationally representative sample of mothers aged 15-49 years. The adjusted results showed that socio-demographic factors such as a maternal age greater than 24 years, living in rural areas and regional variations were positively associated with vitamin A supplementation.

CONCLUSIONS

From the results of the present study, we conclude that socio-demographic factors were influential on vitamin A supplementation in children aged less than 5 years. Therefore, national and community-level efforts to support younger mothers in urban areas in the regions with the lowest coverage are needed to increase the acceptance of vitamin A supplementation, aiming to improve the nutritional status of children and decrease inequity in health.

Bedside Chest Radiography Using Digital Luminescence

The introduction of picture and archiving communicating systems is currently being evaluated in several institutions. We decided, as an intermediate step, to see if image quality after transferral to a personal computer (PC) is sufficient for the diagnostic needs in an intensive care unit. Seventy-five portable digital chest radiographs were studied both as hard-copies and on a monitor after transferral to a PC. Two chest radiologists and one anesthesiologist reviewed the examinations. Our intention was to evaluate if everything that is routinely checked by the anesthesiologist is demonstrable after electronic transfer to a local workstation. We found practically no difference between the performance of monitor and film for the whole material.

Low grandparental social support combined with low parental socioeconomic status is closely associated with obesity in preschool-aged children: a pilot study

While the influence of parental socioeconomic status (SES) on children's weight status is well known, the impact of other family-related aspects such as parental and grandparental social support is less understood. This study investigates the importance of parents' SES and social support (functional and structural) for weight status in a clinical sample of preschoolers 4-6 years old with obesity (n = 39, 56% girls; 73% of parents were overweight/obese, 50% were of non-Swedish origin). Linear regression analyses, simple and multiple, were performed on SES and social support with child BMI SDS (body mass index standard deviation score) as the dependent variable. The results show that parents' income and low emotional support from paternal grandparents were significantly associated with more severe obesity. The association between parental income and the child's BMI SDS was stronger among parents who had low emotional support from their own parents. In conclusion, grandparental social support may be protective against childhood obesity.

Maintained superiority of chronotherapeutics vs. exercise in a 20-week randomized follow-up trial in major depression

OBJECTIVE

To investigate the long-term antidepressant effect of a chronotherapeutic intervention.

METHOD

In this randomized controlled trial 75 patients with major depression were allocated to fixed duloxetine and either a chronotherapeutic intervention (wake group) with three initial wake therapies, daily bright light therapy, and sleep time stabilization or to a group using daily exercise. Patients were followed 29 weeks. We report the last 20 weeks, a follow-up phase, where medication could be altered. Patients were assessed every 4 weeks. Remission rates were primary outcome.

RESULTS

Patients in the wake group had a statistically significant higher remission rate of 61.9% vs. 37.9% in the exercise group at week 29 (OR = 2.6, CL = 1.3-5.6, P = 0.01). This indicated continued improvement compared with the 9 weeks of treatment response (44.8% vs. 23.4%) with maintenance of the large difference between groups. HAM-D17 endpoint scores were statistically lower in the wake group with endpoint scores of 7.5 (SE = 0.9) vs. 10.1 (SE = 0.9) in the exercise group (difference 2.7, CL = 0.5-4.8, P = 0.02).

CONCLUSION

In this clinical study patients continued to improve in the follow-up phase and obtained very high remission rates. This is the first study to show adjunct short-term wake therapy and long-term bright light therapy as an effective and feasible method to attain and maintain remission.

Cytomegalovirus prophylaxis in solid organ transplantation

Human Cytomegalovirus is a commonly identified herpesvirus that establishes a state of latent infection in the majority of the population by adulthood. A coordinated immune response involving both the innate and adaptive immune system prevents active viral replication and disease. Cellular immunity appears particularly important to control of viremia requiring both a CMV-specific CD4+ and CD8+ T cell response. Solid organ transplant recipients are particularly susceptible to CMV related disease due to the immunosuppression necessary to prevent organ rejection, with patients receiving T cell depleting therapies being at highest risk. The deleterious outcomes of CMV in organ transplant recipients result from both direct cytopathic and indirect immune-modulatory effects of CMV viral replication. The recognition of the negative effects of CMV in solid organ transplantation has resulted in the routine prophylaxis of organ recipients with antiviral nucleoside analogues. The appropriate duration of therapy is still controversial although guidelines do exist. The ability to assay an individual immune response to CMV should allow for tailored duration of therapy in the future.

Simultaneously recorded single-exhalation profiles of ethanol, water vapour and CO(2) in humans: impact of pharmacokinetic phases on ethanol airway exchange

The breath alcohol concentration (BrAC) standardized to the alveolar water vapour concentration has been shown to closely predict the arterial blood alcohol (ethanol) concentration (ABAC). However, a transient increase in the ABAC/BrAC ratio has been noted, when alcohol is absorbed from the gastrointestinal tract (absorption phase) and the ABAC rapidly rises. We analysed the plot of simultaneously recorded alcohol, water vapour and CO(2) against exhaled volume (volumetric expirogram) for respiratory dead space volume (VD), cumulative gas output and phase III slope within one breath to evaluate whether changes in the BrAC profile could explain this variability. Eight healthy subjects performed exhalations through pre-heated non-restrictive mouthpieces and the concentrations were measured by infrared absorption. In the absorption phase, the respiratory VD of alcohol was transiently increased and the exhaled alcohol was displaced to the latter part of the expirogram. In the post-absorption phase, the respiratory VD for alcohol and water vapour was stable and always less than the respiratory VD for CO(2), indicating that the first part of the exhaled alcohol and water originated from the conducting airway. The position of the BrAC profile between water vapour and CO(2) in the post-absorptive phase indicates an interaction within the conducting airway, probably including a deposition of alcohol onto the mucosa during exhalation. We conclude that the increase in the ABAC/BrAC ratio during the absorption phase of alcohol coincides with a transient increase in respiratory VD of alcohol and a delay in the appearance of alcohol in the exhaled air as the exhalation proceeds compared with the post-absorption phase.

Is cartilage sGAG content related to early changes in cartilage disease? Implications for interpretation of dGEMRIC

OBJECTIVE

This study investigates sulphated glycosaminoglycans (sGAG) content changes in early osteoarthritis (OA), and whether contrast-enhanced magnetic resonance imaging (MRI) of cartilage in vitro may identify early event of OA pathology.

METHOD

Osteochondral plugs from patients with hip OA or femoral neck fracture (reference group) were collected and analysed by 1.5 T MRI with ΔR1 as a measure of cartilage contrast concentration. Cartilage hydration, contents of sGAG, cartilage oligomeric matrix protein (COMP), hydroxyproline, denatured collagen, and aggrecan TEGE(392) neoepitope were determined and histological grading was performed.

RESULTS

sGAG content correlated to ΔR1, although no difference in either of these parameters was detectable between OA and reference cartilage at 4 h of contrast equilibration. In contrast, biochemical analysis of other cartilage matrix constituents showed distinct alterations typical for early cartilage degradation in OA cartilage and with clear evidence for increased aggrecan turnover.

CONCLUSION

In the present in vitro study, cartilage sGAG content could not distinguish between early OA cartilage and reference cartilage. Given, that delayed gadolinium enhanced MRI of cartilage (dGEMRIC) indicates early events in the pathogenesis of OA in vivo, our results from the in vitro studies imply other, additional factors than cartilage sGAG content, e.g., alterations in diffusion or increased supply of contrast agent in the diseased joint. Alternatively, an altered dGEMRIC reflects later stages of OA, when sGAG content decreases. Further investigations are warranted, to understand variations in sGAG content in pathology, an essential background for interpreting dGEMRIC measurements.

Breath alcohol analysis incorporating standardization to water vapour is as precise as blood alcohol analysis

A novel breath-alcohol analyzer based on the standardization of the breath alcohol concentration (BrAC) to the alveolar-air water vapour concentration has been developed and evaluated. The present study compares results with this particular breath analyzer with arterial blood alcohol concentrations (ABAC), the most relevant quantitative measure of brain alcohol exposure. The precision of analysis of alcohol in arterial blood and breath were determined as well as the agreement between ABAC and BrAC over time post-dosing. Twelve healthy volunteers were administered 0.6g alcohol/kg bodyweight via an orogastric tube. Duplicate breath and arterial blood samples were obtained simultaneously during the absorption, distribution and elimination phases of the alcohol metabolism with particular emphasis on the absorption phase. The precision of the breath analyzer was similar to the determination of blood alcohol concentration by headspace gas chromatography (CV 2.40 vs. 2.38%, p=0.43). The ABAC/BrAC ratio stabilized 30min post-dosing (2089±99; mean±SD). Before this the BrAC tended to underestimate the coexisting ABAC. In conclusion, breath alcohol analysis utilizing standardization of alcohol to water vapour was as precise as blood alcohol analysis, the present "gold standard" method. The BrAC reliably predicted the coexisting ABAC from 30min onwards after the intake of alcohol.

A community-based long-term follow up of women undergoing obstetric fistula repair in rural Ethiopia

OBJECTIVES

To assess urinary and reproductive health and quality of life following surgical repair of obstetric fistula.

DESIGN

Follow-up study.

SETTING

A newly established fistula clinic (2004) at Gimbie Adventist Hospital, a 71-bedded district general hospital in West Wollega Zone, in rural Western Ethiopia.

POPULATION

Thirty-eight women (86%) of 44 who had undergone fistula repair were identified in their community.

METHODS

Community-based structured interviews 14-28 months following fistula repair, using a customised questionnaire addressing urinary health, reproductive health and quality of life.

MAIN OUTCOME MEASURES

Urinary health at follow up was assessed as completely dry, stress or urge incontinence, or fistula. King's Health Questionnaire was modified and used for the quality-of-life assessment.

RESULTS

At follow up, 21 women (57%) were completely dry, 13 (35%) suffered from stress or urge incontinence and three (8%) had a persistent fistula. Surgery improved quality of life and facilitated social reintegration to a level comparable to that experienced before fistula development for both women who were dry and those with residual incontinence (P = 0.001). For women still suffering from fistula no change was seen (P = 0.1). Four women became pregnant following their surgery, among which there was one maternal death, three stillbirths and one re-occurrence of fistula.

CONCLUSION

Community-based, long-term follow up after fistula repair succeeded in Western rural Ethiopia. Despite one-third still suffering stress or urge incontinence, the women reported improved quality of life and social reintegration after fistula closure.

Ethnicity, socio-economic status and self-harm in Swedish youth: a national cohort study

BACKGROUND

Previous studies have shown an elevated risk for self-harm in adolescents from ethnic minorities. However, potential contributions to this risk from socio-economic factors have rarely been addressed. The main aim of this article was to investigate any such effects.

METHOD

A national cohort of 1009 157 children born during 1973-1982 was followed prospectively from 1991 to 2002 in Swedish national registers. Multivariate Cox analyses of proportional hazards were used to estimate the relative risk of hospital admission for self-harm. Parental country/region of birth was used as proxy for ethnicity.

RESULTS

Youth with two parents born outside Sweden (except those from Southern Europe) had higher age- and gender-adjusted hazard ratios (HRs) of self-harm than the majority population (HR 1.6-2.3). The HRs decreased for all immigrant groups when socio-economic factors were accounted for but remained significantly higher for immigrants from Finland and Western countries and for youth with one Swedish-born and one foreign-born parent.

CONCLUSIONS

Socio-economic factors explain much of the variation by parental country of birth of hospital admissions for self-harm in youth in Sweden.

Diagnosis of bacterial kidney disease by detection of Renibacterium salmoninarum by real-time PCR

Bacterial kidney disease (BKD), caused by Renibacterium salmoninarum (Rs), is a serious threat to salmon in aquaculture as well as to wild populations. We have developed a real-time polymerase chain reaction (PCR) for detection of Rs in kidney samples. The PCR is based on detection of unique parts of the 16S rRNA gene of Rs and DNA equivalent to 1-10 Rs genomes was detected per reaction. No cross-reactivity with other fish pathogenic or related bacteria could be demonstrated. Analysis of individual kidney samples collected from BKD classified populations identified 39.9% of the fish as positive by real-time PCR compared with 28.0% by polyclonal enzyme-linked immunosorbent assay (ELISA). The real-time PCR assay was found to be well suited for complementary use with ELISA for diagnosis of BKD, with the ability to detect clinical as well as covert Rs infections. The infection level determined by the polyclonal ELISA and by real-time PCR was significantly correlated.

Repetitive transcranial magnetic stimulation (rTMS) in combination with escitalopram in patients with treatment-resistant major depression: a double-blind, randomised, sham-controlled trial

BACKGROUND

The role of high-frequency rTMS over the left cortex as an add-on strategy in the treatment of major depression is still uncertain even in patients resistant to pharmacotherapy. We had planned a large sham TMS controlled study in the acute phase with a placebo-controlled relapse-prevention phase with escitalopram. However, because a recent meta-analysis showed only a small effect size of rTMS over sham TMS in the acute treatment phase of depressed patients, we decided to make an interim analysis.

METHOD

In patients with medication-resistant major depression we administered in a randomised trial 15 sessions of sham-controlled rTMS over three weeks in combination with 20 mg escitalopram daily. After the last rTMS, the patients were followed for another 9 weeks on 20 mg escitalopram daily. The antidepressant effect was measured by the HAM-D(6) as primary outcome scale.

RESULTS

A total of 45 patients with complete data were randomised so that 23 patients received sham TMS and 22 patients received active, high-frequency rTMS over the left cortex. Over the 3 weeks, the active rTMS treatment was superior to sham TMS with effect sizes on the HAM-D(6) above 0.70, which indicates not only a statistically but also a clinically significant effect. The patients had typically been through two failed antidepressant treatment attempts with non-tricyclics before inclusion in the study. Both the rTMS and escitalopram were well-tolerated.

CONCLUSION

High-frequency rTMS over the left cortex is an add-on strategy of clinical significance in combination with escitalopram in patients with major depression resistant to non-tricyclic antidepressants.

Breath alcohol concentration determined with a new analyzer using free exhalation predicts almost precisely the arterial blood alcohol concentration

A new breath alcohol (ethanol) analyzer has been developed, which allows free exhalation, standardizes measured exhaled alcohol concentration to fully saturated water vapor at a body temperature of 37 degrees C (43.95 mg/L) and includes a built-in self-calibration system. We evaluated the performance of this instrument by comparing standardized alcohol concentration in freely expired breath (BrAC) with arterial (ABAC) and venous (VBAC) blood alcohol concentrations in fifteen healthy volunteers who drank 0.6 g of alcohol per kg body weight. The precision (coefficient of variation, CV) of the analyzer based on in vivo duplicate measurements in all phases of the alcohol metabolism was 1.7%. The ABAC/BrAC ratio was 2251+/-46 (mean+/-S.D.) in the post-absorptive phase and the mean bias between ABAC and BrAC x 2251 was 0.0035 g/L with 95% limits of agreement of 0.033 and -0.026. The ABAC and BrAC x 2251 were highly correlated (r=0.998, p<0.001) and the regression relationship was ABAC = 0.00045 + 1.0069 x (BrAC x 2251) indicating excellent agreement and no fixed or proportional bias. In the absorption phase, ABAC exceeded BrAC x 2251 by at most 0.04+/-0.03 g/L when tests were made at 10 min post-dosing (p<0.05). The VBAC/BrAC ratio never stabilized and varied continuously between 1834 and 3259. There was a proportional bias between VBAC and BrAC x 2251 (ABAC) in the post-absorptive phase (p<0.001). The pharmacokinetic analysis of the elimination rates of alcohol and times to zero BAC confirmed that BrAC x 2251 and ABAC agreed very well with each other, but not with VBAC (p<0.001). We conclude that this new breath analyzer using free exhalation has a high precision for in vivo testing. The BrAC reflects very accurately ABAC in the post-absorption phase and substantially well in the absorption phase and thereby reflects the concentration of alcohol reaching the brain. Our findings highlight the magnitude of arterio-venous differences in alcohol concentration and support the use of breath alcohol analyzers as a stand-alone test for medical and legal purposes.

Birth outcomes and pregnancy complications in women with a history of anorexia nervosa

OBJECTIVE

To examine birth outcomes and pregnancy complications in women with a history of anorexia nervosa.

DESIGN

Prospective cohort study.

SETTING

Nationwide study in Sweden.

POPULATION

All primiparous women--discharged from hospital with a diagnosis of anorexia nervosa during 1973 to 1996--who gave birth during 1983 to 2002 (n = 1000) were compared with all non-anorexia nervosa primiparous women who gave birth during the same years (n = 827,582).

METHOD

Register study with data from Medical Birth Registry and National Patient Discharge Register.

MAIN OUTCOME MEASURES

Pre-eclampsia, instrumental delivery, prematurity, small for gestational age, birthweight, Apgar score and perinatal mortality.

RESULTS

Main birth outcome measures in women with a history of anorexia nervosa were very similar to the main population. The only observed differences were a slightly lower mean birthweight and lower adjusted odds ratios for instrumental delivery in the anorexia nervosa group compared with the main population. Neither severity of the disease nor a shorter recovery phase after first hospitalisation was related to pregnancy complications or birth outcomes.

CONCLUSION

A history of anorexia nervosa was not associated with negative birth outcomes. Thus, special obstetric monitoring of pregnant women with history of anorexia nervosa does not seem to be warranted in a country with a satisfactory maternity surveillance.

Effects of dexamethasone on clinical course, C-reactive protein, S100B protein and von Willebrand factor antigen after paediatric cardiac surgery

BACKGROUND

Anti-inflammatory treatment with glucocorticoids during cardiopulmonary bypass can reduce inflammatory mediator release, but the effects of glucocorticoid on outcome are controversial.

METHODS

We studied the effects of dexamethasone on clinical course, C-reactive protein, von Willebrand factor antigen (vWf:Ag) and S100B in a randomized masked study of children after open cardiac surgery. Twenty children weighing >10 kg received dexamethasone (1 mg kg(-1)) and 20 controls received saline after induction of anaesthesia. We measured vWf:Ag as a marker of endothelial activation, S100B as a marker of cerebral protein release and C-reactive protein as a marker of inflammatory activity. Oxygenation, body temperature, fluid balance, leucocyte and platelet counts, days in the intensive care unit (ICU) and days on mechanical ventilation were noted.

RESULTS

Dexamethasone decreased C-reactive protein concentration on the first postoperative day (P<0.05), but did not affect the release of vWf:Ag or S100B. There was no significant difference in oxygenation, body temperature, fluid balance, leucocyte and platelet counts, days in the ICU or days on mechanical ventilation between the placebo and dexamethasone-treated groups.

CONCLUSION

Administration of dexamethasone before cardiopulmonary bypass for paediatric cardiac surgery decreased the inflammatory response, but did not affect the immediate features after surgery or changes in vWf:Ag or S100B.

Human-animal interactions and animal welfare in conventionally and pen-housed rats

The main aim of the present study was to explore the significance of large group/greater pen housing (PH) versus standard Makrolon caging (ST) in three behaviour tests related to human-animal interactions in the adult male laboratory rat. The rats' perception of human interaction was tested in three behavioural tests, of which two reflected common practical procedures, capture and restraint, whereas the third was a human approach test in a Y-maze. The rats' anticipatory reactions to handling and the reactions to restraint did not differ between groups, but the ST rats approached a human hand more quickly than did the PH rats (P < 0.01). Although food intake did not differ, ST rats gained more weight (P < 0.01) and had higher total cholesterol values (P < 0.01) than PH rats. In conclusion, this study shows that housing rats in large groups in an enriched environment did not influence their anticipatory reaction to handling in normal handling situations. However, as the PH rats tended to have a longer approach latency than ST rats in the Y-maze there might be underlying differences in appraisal that are not detected in practical situations. In addition, the PH rats weighed less and had lower total cholesterol values than ST rats and their urine corticosterone values were higher. These effects are suggested to be due to higher physical activity in the PH rats, and the implications of this on the animal as a model is discussed.

How common is severe pulmonary hypertension after pediatric cardiac surgery?

BACKGROUND

Pulmonary hypertension may result in significant morbidity and mortality after pediatric cardiac surgery. The objective of this study was to determine the incidence and outcome of severe pulmonary hypertension, defined as a ratio of pulmonary to systemic arterial pressure equal to or greater than 1.0, after cardiac surgery in children.

METHODS

Data from all children younger than 18 years who had undergone cardiothoracic surgery from January 1, 1994, to December 31, 1998, were examined. To find children with severe pulmonary hypertension, we reviewed intensive care unit charts from patients who had been monitored with a pulmonary artery catheter after the operation (n = 151), had received mechanical ventilation for more than 4 days after the operation (n = 124), or had died in the operating room or the intensive care unit (n = 22). Intraoperative and postoperative measurements of mean pulmonary arterial pressure and postoperative echocardiographic studies during the first 3 postoperative days were used to select the children.

RESULTS

During the study period, 1349 children (including 164 neonates and 511 infants, median age 12 months) underwent cardiac operations with an overall perioperative mortality of 22 patients (1.6%). Twenty-seven children (2%, median age 4.2 months) had severe pulmonary hypertension. Of these, 2 (7.4%) died within 30 days of the operation, and 3 others (11%) died within a year (median follow-up 53 months). Nitric oxide inhalation was used in 5 of the 27 cases, and it probably saved the life of 1 patient, may have helped in 1 case, and had no discernible effect in 3 cases. Severe pulmonary hypertension was most common after correction of complete atrioventricular septal defects (14%, n = 12/85). Thirteen of 131 children with Down syndrome (9.9%) had severe pulmonary hypertension.

CONCLUSION

Severe postoperative pulmonary hypertension occurred after 2% of the cardiac procedures and in most cases was managed successfully with conventional treatment and had a favorable postoperative outcome. The low incidence relative to previous reports may reflect the benefits of early correction and improved intraoperative and postoperative care.

Mechanical impedance of the human body in vertical direction

The mechanical impedance of the human body in sitting posture and vertical direction was measured during different experimental conditions, such as vibration level (0.5-1.4 m/s2), frequency (2-100 Hz), body weight (57-92 kg), relaxed and erect upper body posture. The outcome shows that impedance increases with frequency up to a peak at about 5 Hz after which it decreases in a complex manner which includes two additional peaks. The frequency at which the first and second impedance peak occurs decreases with higher vibration level. Erect, compared with relaxed body posture resulted in higher impedance magnitudes and with peaks located at somewhat higher frequencies. Heavy persons show higher impedance magnitudes and peaks at lower frequencies.

Performance of Uricult Trio assessed by a comparison method and external control panels in primary healthcare

Using the comparison method, we have evaluated the technical performance of Uricult Trio by culturing on Uricult Trio and agar plates. Urine samples (477) from patients in primary healthcare were cultured in parallel in a microbiology laboratory. The result for Uricult Trio evaluated using the comparison method was incorrect in 32% of the cultures. We also studied the performance of Uricult Trio when used in primary healthcare by using external control panels. External control panels consisting of Uricult Trio, inoculated with known concentrations of certain bacterial strains, were used to assess the performance of Uricult Trio in primary healthcare during the period 1993-7. Aberrations in reports of concentration have ranged from 10% to 33%, failure in reporting of mixed culture from 0% to 91% and reporting of E. coli from 15% to 86%. There has been no sign of improvement over the years. The results indicate that Uricult Trio is unsuitable for indications other than exclusion of urinary tract infection or diagnosis of urinary tract infection caused by E. coli. Further, there is need for quality assurance and training activities at primary healthcare laboratories, probably best carried out in collaboration with local clinical microbiology laboratories.

Fat infiltration in liver and activity of lecithin:cholesterol acyltransferase in serum of dry and lactating dairy cows

To study the relationship between fat infiltration in the liver and the decrease in the activity of serum lecithin:cholesterol acyltransferase (LCAT), blood and liver samples were taken from 14 multiparous (MP) and 16 primiparous (PP) dairy cows four weeks and one week before, and one, four and eight weeks after calving. During the dry period, half the animals received a protein supplement. LCAT activity decreased significantly in all groups before parturition, but returned to the initial level within 1-4 weeks after parturition. There were no differences between the feeding groups, but after calving, the LCAT activity in the MP cows was significantly lower than in the PP cows. Fat infiltration was not detected in the PP cows, and in the MP cows fat infiltration was mild and fell within the physiological range. There was no correlation between liver fat content and the activity of LCAT in serum. These results suggest that shortly before and after parturition, the activity of LCAT in serum is limited by post-transcriptional regulation, possibly by the availability of amino acid for export protein synthesis in the liver.

The effects of epinephrine/norepinephrine on end-tidal carbon dioxide concentration, coronary perfusion pressure and pulmonary arterial blood flow during cardiopulmonary resuscitation

End-tidal CO2 concentration correlates with pulmonary blood flow during cardiopulmonary resuscitation and has been claimed to be a useful tool to judge the effectiveness of chest compression. A high concentration of end-tidal CO2 has been related to a better outcome. However, most authors have noticed a decrease in end-tidal CO2 concentration after administration of epinephrine, concomitant with an increase in coronary perfusion pressure and an increased incidence of return of spontaneous circulation. This study was performed to evaluate changes in end-tidal CO2 concentration after injection of vasopressors during cardiopulmonary resuscitation and to investigate the time-course of the response and possible explanations for it. After 1 min of electrically induced cardiac arrest and 5 min of chest compressions, 18 pigs were randomly assigned to receive 0.045 mg kg(-1) epinephrine, 0.045 mg kg(-1) norepinephrine or no drug. After another 4 min of chest compressions the pigs were defibrillated. End-tidal CO2, pulmonary blood flow and coronary perfusion pressure decreased immediately after the induction of cardiac arrest, increased slightly during chest compressions and increased initially to supernormal levels after the return of spontaneous circulation. Injection of epinephrine or norepinephrine during chest compressions decreased end-tidal CO2 51 +/- 2%, (mean +/- S.E.M.), and 43 +/- 1%, respectively, and pulmonary blood flow by 134 +/- 13 and 125 +/- 16%, respectively, within 1 min, simultaneously increasing coronary perfusion pressure from 10 +/- 2 to 45 +/- 5 mm Hg and from 11 +/- 1 to 38 +/- 5 mm Hg, respectively. The coronary perfusion pressure slowly fell, but the effects on end-tidal CO2 and pulmonary blood flow were prolonged. In conclusion, vasopressors increased coronary perfusion pressure and the likelihood of a return of spontaneous circulation, but decreased end-tidal CO2 concentration and induced a critical deterioration in cardiac output and thus oxygen delivery in this model of cardiopulmonary resuscitation.

Effects of rhBMP-2 and osteopromotive membranes on experimental bone grafting

A problem with using autogeneic bone for onlay grafting is its degree of incorporation and volumetric persistence. This study explored whether improved graft volumetric maintenance can be achieved by recombinant human bone morphogenetic protein-2 (rhBMP-2) and whether a combination of rhBMP-2 and osteopromotive membranes is advantageous in this respect. Unicortico-cancellous bone grafts were positioned below the temporal muscle bilaterally in 48 adult Lewis rats. The recipient bone was ground, and the grafted area was randomly treated according to one of eight different alternatives. Two doses of rhBMP-2 (4 microg/80 microl or 32 microg/80 microl buffer) in a collagenous carrier were tested, with or without coverage with expanded polytetrafluoroethylene membranes. As controls, membrane and carrier, alone or in combination, and onlay grafts only were used. The results were evaluated after 4 and 20 weeks by routine histologic examination and immunohistochemical labeling for various bone and cartilage matrix proteins. After 4 weeks, rhBMP-2-treated grafts showed complete integration, whereas for controls, only the membrane-alone group attained incorporation after 20 weeks. The combined treatment with high-dose rhBMP-2 and membrane demonstrated, as compared with the remaining rhBMP-2 groups, pronounced bone formation and less graft resorption, resulting in maintained or increased graft size. This was observed after 4 weeks, and the result remained at 20 weeks. Treatment with high-dose rhBMP-2 without membrane placement, in contrast, resulted in extensive resorption and graft size reduction at 20 weeks. Control groups showed less success in graft size persistence. It was concluded that a combination of high-dose rhBMP-2 and osteopromotive membranes had a synergistic effect, leading to rapid, complete graft integration and size maintenance. In the absence of a membrane, the protein seemed to accelerate the remodeling of the graft.

Production of nitrogen dioxide during nitric oxide therapy using the Servo Ventilator 300 during volume-controlled ventilation

BACKGROUND

Inhaled nitric oxide may be useful in the treatment of pulmonary hypertension and hypoxaemia. Nitric oxide is rapidly oxidized to nitrogen dioxide, which is toxic and may adversely affect the airways of the patient. The aim of the present investigation was to examine factors that may affect the concentration of nitrogen dioxide, using the Servo Ventilator 300 nitric oxide delivery system, where nitric oxide is flow-proportionally mixed with the main ventilatory flow in the proximal part of the inspiratory limb.

METHODS

In this experimental study nitric oxide and nitrogen dioxide levels were measured at the inspiratory site of a Y-piece with a chemiluminescence analyzer and electrochemical fuel cells. The effects of different concentrations of nitric oxide and oxygen, minute volume, different tube lengths, a soda lime absorber, and a humidifier placed in the inspiratory limb were evaluated.

RESULTS

The concentration of nitrogen dioxide was dependent on the concentrations and residence time of nitric oxide with oxygen and the minute volume ventilation used. A soda lime absorber reduced concentrations of nitrogen dioxide at the expense of almost corresponding reductions in inhaled concentrations of nitric oxide. A humidifier increased the concentration of nitrogen dioxide, to an extent depending on the water volume and temperature used.

CONCLUSION

Concentrations of nitric oxide and oxygen, minute volume ventilation, and residence time in the inspiratory part of the ventilatory circuit were factors that affected the generation of nitrogen dioxide. A soda lime absorber in this system is not recommended.

Evaluation of nitrogen dioxide scavengers during delivery of inhaled nitric oxide

We have analysed the ability of three nitrogen dioxide absorbing materials (soda lime, noXon and zeolite) to act as nitrogen dioxide scavengers during delivery of inhaled nitric oxide. Different mixtures of gas were produced in a ventilator (Servo Ventilator 300) and passed through an inspiratory tube. Concentrations of nitrogen dioxide and nitric oxide were measured in the distal part of the tube, with and without the gas having passed through a canister containing the different filter materials. Our findings indicated that nitrogen dioxide was absorbed effectively by all filter materials but that there was re-formation of nitrogen dioxide from nitric oxide and oxygen in or immediately after the canister. This initial production of nitrogen dioxide was very rapid and could not be prevented by the use of scavengers. Thus soda lime and zeolite had no practical effect as scavengers in this delivery system, and the effect of noXon was very slight.

Serum S-100 protein levels after pediatric cardiac operations: a possible new marker for postperfusion cerebral injury

BACKGROUND

The release of neuron-specific astroglial S-100 protein to the cerebrospinal fluid is a marker of cerebral damage. The aim of this study was to determine the pattern of release of S-100 protein to serum after pediatric cardiac operations and extracorporeal circulation.

METHODS

Sequential blood samples from 97 children (up to 16 years) were taken after induction of anesthesia, immediately after the discontinuation of extracorporeal circulation, and 5 and 15 hours after extracorporeal circulation. The children were divided into five groups including three age groups, children with Mb Down syndrome, and children undergoing circulatory arrest.

RESULTS

The serum concentrations of S-100 protein before the cardiac operation were found to be highest in neonates. Children with Down syndrome, regardless of age, had basal levels comparable to those in neonates. There was an increase in S-100 protein concentration immediately after extracorporeal circulation and a multivariate regression analysis showed this difference in S-100 protein concentration to be significant with respect to age (p = 0.002), perfusion time (p < 0.001), and circulatory arrest (p < 0.001), but the difference was not significant with respect to weight, Down syndrome, and core temperature (p > 0.8). In children younger than 1 month old and after circulatory arrest, levels of S-100 protein remained high at 5 hours after extracorporeal circulation.

CONCLUSION

These findings emphasize the necessity of using age-matched reference values and taking perfusion time into consideration when S-100 protein levels are evaluated with respect to cerebral postperfusion injuries in pediatric patients undergoing cardiac operations.

[A new study of patients with cancer in Umeå alternative medicine is no alternative]

A questionnaire study comprising 854 cancer patients in the Umeå health care region and covering the 10-year period, 1987-96, showed only a few cancer patients to use alternative medicine treatment for their disease. As compared with 19.4 per cent of 144 residents selected from the population register who answered the questionnaire in 1987, 16.8 per cent of the cancer patients reported using alternative treatments in 1987, 14.4 per cent in 1990, and 16.4 per cent in 1996. The commonest forms of alternative medicine used were chiropractic and acupuncture, and the majority of treatments were for pain in the muscles or musculoskeletal system.

Absorption of energy during vertical whole-body vibration exposure

Absorbed power (PAbs) during exposure to vertical whole-body vibration in a sitting posture was measured on 15 male and 15 female subjects. Different experimental conditions were applied, such as vibration level (0.5-1.4 m s(-2)) and frequency (2-100 Hz), body weight (54-93 kg) and, relaxed and erected upper body positions. Results show that PAbs was strongly related to the frequency of the vibration, peaking within the range of 4-6 Hz. The peak was predominantly located in the lower end of this range for females and for the relaxed sitting position. PAbs increased with acceleration level and body weight. Almost a ten-fold increase in PAbs was observed at the critical frequency when the vibration exposure was raised from 0.5 to 1.4 m s(-2). If risk assessment is based on the assumption that the amount of PAbs, independent of the frequency of the vibration, indicates a hazard, then the ISO-standard 2631 under- and overestimates the risk at frequencies below and above about 6 Hz, respectively. The results also indicate a need for differentiated guidelines for females and males. Many types of vehicles produce whole-body vibration with frequencies which coincide with the range where the highest PAbs was observed. PAbs is a 'new' concept for measurement of whole-body vibration exposure. Although not yet thoroughly evaluated, this measure may be a better quantity for risk assessment than those specified in ISO 2631 since it also takes the dynamic force applied to the human body into account.

Osteopromotive membranes enhance onlay integration and maintenance in the adult rat skull

This study aimed to evaluate the effect of an osteopromotive membrane technique on onlay bone graft survival. Unicortical bone grafts were positioned bilaterally below the temporal muscle in 21 adult Lewis rats. In 14 rats, the bone graft on the right side was covered by an expanded polytetrafluoroethylene GORE-TEX membrane, whereas that on the left side was left uncovered. Seven rats were killed after 12 (group 1) and 20 (group 2) weeks, respectively. The remaining animals (n = 7, group 3) received membranes bilaterally, of which the right-sided membrane was removed after 12 weeks, and these animals were killed after 20 weeks. The specimens were assessed by routine histology and immunohistochemical labelling for various matrix proteins. After 12 weeks (group 1), size differences between the sides were not significant, although all control onlay bone grafts showed microscopic signs of pronounced resorption. At 20 weeks (group 2), graft integration was more complete on the membrane side. For group 3, the height was significantly more preserved on the side where the membrane was not removed. Immunolabelling demonstrated a more intense bone remodelling at the membrane sites. Membrane treatment resulted in improved graft integration and significantly greater size persistence, but complete height was not maintained.

Production of nitrogen dioxide in a delivery system for inhalation of nitric oxide: a new equation for calculation

We have evaluated the kinetics of nitrogen dioxide production in a system for inhalation of nitric oxide. In addition to a small fraction of contamination of nitrogen dioxide in the nitric oxide stock gas, a considerable part of the total concentration of nitrogen dioxide is formed immediately after mixing of nitric oxide and oxygen. This initial build-up of nitrogen dioxide is followed by a linear, time-dependent increase in the concentration of nitrogen dioxide. An equation describing the concentration of nitrogen dioxide in the delivery system is formulated: [NO2] = kA x [NO] + kB x [NO]2 x [O2] + kC x t x [NO]2 x [O2], where nitrogen dioxide [NO2] and nitric oxide [NO] concentrations are in parts per million (ppm), oxygen concentration [O2] is expressed as a percentage and contact time (t) is in seconds. The rate constants are kA = 5.12 x 10(-3), kB = 1.41 x 10(-6) and kC = 0.86 x 10(-6). Calculated nitrogen dioxide values correlated well with measured concentrations. This new finding of an initial build-up of nitrogen dioxide has to be taken into consideration if the conversion of nitric oxide to nitrogen dioxide is to be calculated and in the safety guidelines for the use of nitric oxide.

Bone graft incorporation after cortical perforations of the host bed

A fundamental issue in onlay bone graft persistence is the unpredictable extent of incorporation and volumetric maintenance of the graft. The purpose of this study was to evaluate the effects on integration of onlays, with either their cancellous or cortical portion facing toward the host bed, positioned over cortical perforations at the recipient site. Tibial or femoral unicortical bone grafts were harvested from isogeneic donors and positioned subperiostally on each tibia of 22 adult Lewis rats. On the experimental side, the recipient outer cortical bone surface received multiple perforations, 0.25 mm in diameter. The contralateral side served as a control (no cortical perforations). The findings were assessed after 4 and 20 weeks using routine histologic and immunohistochemistry techniques. Cortical perforations induced a migration of the recipient bone marrow into the graft as well as a reduced size diminution. More cortical bone remodeling and marginal lamellar bone apposition were observed after orientating the cortical portion of the graft toward the recipient site. These observations may be useful clinically to improve long-term success after autogeneic bone grafting.

Bone Graft Incorporation after Cortical Perforations of the Host Bed

A fundamental issue in onlay bone graft persistence is the unpredictable extent of incorporation and volumetric maintenance of the graft. The purpose of this study was to evaluate the effects on integration of onlays, with either their cancellous or cortical portion facing toward the host bed, positioned over cortical perforations at the recipient site. Tibial or femoral unicortical bone grafts were harvested from isogeneic donors and positioned sub-periostally on each tibia of 22 adult Lewis rats. On the experimental side, the recipient outer cortical bone surface received multiple perforations, 0.25 mm in diameter. The contralateral side served as a control (no cortical perforations). The findings were assessed after 4 and 20 weeks using routine histologic and immunohistochemistry techniques. Cortical perforations induced a migration of the recipient bone marrow info the graft as well as a reduced size diminution. More cortical bone remodeling and marginal lamellar bone apposition were observed after orientating the cortical portion of the graft toward the recipient site. These observations may be useful clinically to improve long-term success after autogeneic bone grafting.

A delivery system for inhalation of nitric oxide evaluated with chemiluminescence, electrochemical fuel cells, and capnography

OBJECTIVE

To evaluate a system for delivery of inhaled nitric oxide.

DESIGN

Prospective, laboratory study.

SETTING

Engineering laboratory.

SUBJECTS

A standard ventilator (Servo Ventilator 300), supplemented with extra gas modules for nitric oxide delivery.

INTERVENTIONS

Two ventilator-integrated gas modules, delivering < or = 10 parts per million (ppm) or < or = 100 ppm of nitric oxide, were used in adult and neonatal modes during volume-controlled ventilation. Set nitric oxide concentration and FIO2 were systematically changed and compared with the measured concentration. Short-term mixing was tested in adult, pediatric, and neonatal modes by substituting nitric oxide with CO2, and measuring the delivered concentration by a fast-response CO2 analyzer during five successive respiratory cycles. Long-term mixing was tested with the administration of 25 ppm of nitric oxide for 7 days.

MEASUREMENTS AND MAIN RESULTS

Delivered concentration of nitric oxide and nitrogen dioxide were simultaneously measured at the Y-place by two methods-chemiluminescence and electro-chemical fuel cells. The maximum absolute difference between set and measured concentrations of nitric oxide in the adult mode was 0.6 ppm at a set concentration of 10 ppm and 2.7 ppm at a set concentration of 100 ppm. In the neonatal mode, the maximal difference was 3.1 ppm at a set concentration of 100 ppm. Nitrogen dioxide concentration increased with increasing concentration of nitric oxide and oxygen to 2.6 ppm (as measured by the chemiluminescence analyzer) and 3.6 ppm (as measured by the electro-chemical fuel cell), at a setting of 100 ppm of nitric oxide with an FIO2 of 0.90 in the neonatal mode (2 L/min). During the short-term test of mixing stability throughout the respiratory cycles, a constant set CO2 concentration varied maximally by +/-6.2% from the set value in the neonatal mode, whereas the variance was by +/-6.5% in pediatric mode, and by +/-8.0% in the adult mode. During the long-term test, nitric oxide concentration varied maximally by +/-2.6% (as measured by the chemiluminescence analyzer) and by +/-2.3% (as measured by the electrochemical fuel cell).

CONCLUSIONS

An accurate precision in delivered nitric oxide concentration was achieved during intermittent flow ventilation, and this accuracy was independent of tested ventilator settings. The delivery system administered an almost stable concentration throughout a respiratory cycle and during long-term delivery. If the mixing point is in the inspiratory part of the ventilator, valid measurement of nitric oxide and nitrogen dioxide delivery concentrations are possible. Both techniques for measuring nitric oxide and nitrogen dioxide have drawbacks.

Inhaled nitric oxide reveals and attenuates endothelial dysfunction after lung transplantation

BACKGROUND

Maintaining endothelial function within transplanted organs may be critical to successful preservation. In this study we have evaluated the relationship between the effect of inhalation of nitric oxide and the degree of endothelial dysfunction after lung transplantation.

METHODS

A left lung, which had been preserved for 24 hours, was transplanted and a right pneumonectomy was performed in 5 pigs. After a 24-hour observation period the pigs inhaled 5, 20, and 80 ppm nitric oxide, and pulmonary vascular resistance was recorded continuously. From the same donors preserved pulmonary arteries from the contralateral lung were studied simultaneously in organ baths. Acetylcholine chloride was used to elicit endothelium-dependent relaxation in vessel segments contracted with the thromboxane A2 analogue U-46619.

RESULTS

Maximal endothelium-dependent relaxation decreased in the preserved lungs and correlated to the pulmonary vascular resistance in the simultaneously transplanted lungs. Inhalation of nitric oxide in the pigs that had received transplants caused the pulmonary vessels to dilate in proportion to the endothelial dysfunction.

CONCLUSIONS

Preservation of lung for transplantation induces an endothelial dysfunction, and the degree of the decrease in pulmonary vascular resistance caused by nitric oxide inhalation may be an indication of the degree of this endothelial damage. The vasodilation caused by inhaled nitric oxide increases as the endothelial function deteriorates.