Lower levels of Th1 and Th2 cytokines in cerebrospinal fluid (CSF) at the time of initial CSF shunt placement in children are associated with subsequent shunt revision surgeries

OBJECTIVE

We compare cytokine profiles at the time of initial CSF shunt placement between children who required no subsequent shunt revision surgeries and children requiring repeated CSF shunt revision surgeries for CSF shunt failure. We also describe the cytokine profiles across surgical episodes for children who undergo multiple subsequent revision surgeries.

METHODS

This pilot study was nested within an ongoing prospective multicenter study collecting CSF samples and clinical data at the time of CSF shunt surgeries since August 2014. We selected cases where CSF was available for children who underwent an initial CSF shunt placement and had no subsequent shunt revision surgeries during >=24 months of follow-up (n = 7); as well as children who underwent an initial CSF shunt placement and then required repeated CSF shunt revision surgeries (n = 3). Levels of 92 human cytokines were measured using the Olink immunoassay and 41 human cytokines were measured using Luminex based bead array on CSF obtained at the time of each child's initial CSF shunt placement and were displayed in heat maps.

RESULTS

Qualitatively similar profiles for the majority of cytokines were observed among the patients in each group in both Olink and Luminex assays. Lower levels of MCP-3, CASP-8, CD5, CXCL9, CXCL11, eotaxin, IFN-γ, IL-13, IP-10, and OSM at the time of initial surgery were noted in the children who went on to require multiple surgeries. Pro- and anti-inflammatory cytokines were selected a priori and shown across subsequent revision surgeries for the 3 patients. Cytokine patterns differed between patients, but within a given patient pro-inflammatory and anti-inflammatory cytokines acted in a parallel fashion, with the exception of IL-4.

CONCLUSIONS

Heat maps of cytokine levels at the time of initial CSF shunt placement for each child undergoing only a single initial CSF shunt placement and for each child undergoing repeat CSF shunt revision surgeries demonstrated qualitatively similar profiles for the majority of cytokines. Lower levels of MCP-3, CASP-8, CD5, CXCL9, CXCL11, eotaxin, IFN-γ, IL-13, IP-10, and OSM at the time of initial surgery were noted in the children who went on to require multiple surgeries. Better stratification by patient age, etiology, and mechanism of failure is needed to develop a deeper understanding of the mechanism of inflammation in the development of hydrocephalus and response to shunting in children.

Evaluating the ability of a locally focused culling program in removing chronic wasting disease infected free-ranging white-tailed deer in Illinois, USA, 2003-2020

In northern Illinois, chronic wasting disease (CWD) was first identified in free-ranging white-tailed deer (Odocoileus virginianus; hereafter referred to as "deer") in 2002. To reduce CWD transmission rates in Illinois, wildlife biologists have conducted locally focussed culling of deer since 2003 in areas where CWD has been detected. We used retrospective spatial, temporal and space-time scan statistical models to identify areas and periods where culling removed higher than expected numbers of CWD-positive deer. We included 490 Public Land Survey "sections" (∼2.59 km² ) from 15 northern Illinois counties in which at least one deer tested positive for CWD between 2003 and 2020. A negative binomial regression model compared the proportion of CWD positive cases removed from sections with at least one CWD case detected in the previous years, "local area 1 (L1)," to the proportion of CWD cases in adjacent sections-L2, L3, and L4-designated by their increasing distance from L1. Of the 14,661 deer removed and tested via culling, 325 (2.22 %) were CWD-positive. A single temporal CWD cluster occurred in 2020. Three spatial clusters were identified, with a primary cluster located at the border of Boone and Winnebago counties. Four space-time clusters were identified with a primary cluster in the northern portion of the study area from 2003 to 2005 that overlapped with the spatial cluster. The proportion of CWD cases removed from L1 (3.92, 95% CI, 2.56-6.01) and L2 (2.32, 95% CI, 1.50-3.59) were significantly higher compared to L3. Focussing culling efforts on accessible properties closest to L1 areas results in more CWD-infected deer being removed, which highlights the value of collaborations among landowners, hunters, and wildlife management agencies to control CWD. Continuous evaluation and updating of the culling and surveillance programs are essential to mitigate the health burden of CWD on deer populations in Illinois.

Differences in obstetrical care and outcomes associated with the proportion of the obstetrician's shift completed

BACKGROUND

Understanding and improving obstetrical quality and safety is an important goal of professional societies, and many interventions such as checklists, safety bundles, educational interventions, or other culture changes have been implemented to improve the quality of care provided to obstetrical patients. Although many factors contribute to delivery decisions, a reduced workload has addressed how provider issues such as fatigue or behaviors surrounding impending shift changes may influence the delivery mode and outcomes.

OBJECTIVE

The objective was to assess whether intrapartum obstetrical interventions and adverse outcomes differ based on the temporal proximity of the delivery to the attending's shift change.

STUDY DESIGN

This was a secondary analysis from a multicenter obstetrical cohort in which all patients with cephalic, singleton gestations who attempted vaginal birth were eligible for inclusion. The primary exposure used to quantify the relationship between the proximity of the provider to their shift change and a delivery intervention was the ratio of time from the most recent attending shift change to vaginal delivery or decision for cesarean delivery to the total length of the shift. Ratios were used to represent the proportion of time completed in the shift by normalizing for varying shift lengths. A sensitivity analysis restricted to patients who were delivered by physicians working 12-hour shifts was performed. Outcomes chosen included cesarean delivery, episiotomy, third- or fourth-degree perineal laceration, 5-minute Apgar score of <4, and neonatal intensive care unit admission. Chi-squared tests were used to evaluate outcomes based on the proportion of the attending's shift completed. Adjusted and unadjusted logistic models fitting a cubic spline (when indicated) were used to determine whether the frequency of outcomes throughout the shift occurred in a statistically significant, nonlinear pattern RESULTS: Of the 82,851 patients eligible for inclusion, 47,262 (57%) had ratio data available and constituted the analyzable sample. Deliveries were evenly distributed throughout shifts, with 50.6% taking place in the first half of shifts. There were no statistically significant differences in the frequency of cesarean delivery, episiotomy, third- or fourth-degree perineal lacerations, or 5-minute Apgar scores of <4 based on the proportion of the shift completed. The findings were unchanged when evaluated with a cubic spline in unadjusted and adjusted logistic models. Sensitivity analyses performed on the 22.2% of patients who were delivered by a physician completing a 12-hour shift showed similar findings. There was a small increase in the frequency of neonatal intensive care unit admissions with a greater proportion of the shift completed (adjusted P=.009), but the findings did not persist in the sensitivity analysis.

CONCLUSION

Clinically significant differences in obstetrical interventions and outcomes do not seem to exist based on the temporal proximity to the attending physician's shift change. Future work should attempt to directly study unit culture and provider fatigue to further investigate opportunities to improve obstetrical quality of care, and additional studies are needed to corroborate these findings in community settings.

Immediate replacement of bone flap after craniotomy for empyema in children

PURPOSE

Optimal management of the bone flap after craniotomy for intracranial infection has not been well defined in the pediatric population. This study reviewed the outcomes of a single Canadian center where immediate replacement of the bone flap was standard practice.

METHODS

This is a retrospective study of all patients who underwent craniotomies for evacuation of epidural or subdural empyema at a single center from 1982 to 2018. Patients were identified using the prospective surgical database maintained by the Division of Pediatric Neurosurgery at BC Children's Hospital. Primary outcome was treatment failure, defined as reoperation at the site of initial surgery for removal of an infected bone flap or repeat drainage of empyema under the replaced bone flap. Secondary outcome was any reoperation for recurrent infection at any site.

RESULTS

Twenty-four patients met the inclusion criteria with a minimum of 3-month follow-up from the index intervention. Treatment failure occurred in four patients (17%), all of whom required repeat surgery for further drainage of pus underlying the bone flap. Mean time to repeat surgery was 13 days. Any reoperation for recurrent infection at any site occurred in three patients. Seven out of 24 patients required a second surgery to evacuate empyema (29.2%). Age, sex, epidural or subdural location, osteomyelitis, and bone flap wash were not associated with the primary outcome of treatment failure.

CONCLUSION

Immediate replacement of the bone flap in the surgical management of pediatric subdural or epidural empyema is reasonable. Replacing the flap at the time of first surgery avoids the morbidity and costs of a subsequent reconstructive operation.

Cranial and ventricular size following shunting or endoscopic third ventriculostomy (ETV) in infants with aqueductal stenosis: further insights from the International Infant Hydrocephalus Study (IIHS)

PURPOSE

The craniometrics of head circumference (HC) and ventricular size are part of the clinical assessment of infants with hydrocephalus and are often utilized in conjunction with other clinical and radiological parameters to determine the success of treatment. We aimed to assess the effect of endoscopic third ventriculostomy (ETV) and shunting on craniometric measurements during the follow-up of a cohort of infants with symptomatic triventricular hydrocephalus secondary to aqueductal stenosis.

METHODS

We performed a post hoc analysis of data from the International Infant Hydrocephalus Study (IIHS)-a prospective, multicenter study of infants (< 24 months old) with hydrocephalus from aqueductal stenosis who were treated with either an ETV or shunt. During various stages of a 5-year follow-up period, the following craniometrics were measured: HC, HC centile, HC z-score, and frontal-occipital horn ratio (FOR). Data were compared in an analysis of covariance, adjusting for baseline variables including age at surgery and sex.

RESULTS

Of 158 enrolled patients, 115 underwent an ETV, while 43 received a shunt. Both procedures led to improvements in the mean HC centile position and z-score, a trend which continued until the 5-year assessment point. A similar trend was noted for FOR which was measured at 12 months and 3 years following initial treatment. Although the values were consistently higher for ETV compared with shunt, the differences in HC value, centile, and z-score were not significant. ETV was associated with a significantly higher FOR compared with shunting at 12 months (0.52 vs 0.44; p = 0.002) and 3 years (0.46 vs 0.38; p = 0.03) of follow-up.

CONCLUSION

ETV and shunting led to improvements in HC centile, z-score, and FOR measurements during long-term follow-up of infants with hydrocephalus secondary to aqueductal stenosis. Head size did not significantly differ between the treatment groups during follow-up, however ventricle size was greater in those undergoing ETV when measured at 1 and 3 years following treatment.

Metrics of progress in the understanding and management of threats to Australian birds

Although evidence-based approaches have become commonplace for determining the success of conservation measures for the management of threatened taxa, there are no standard metrics for assessing progress in research or management. We developed 5 metrics to meet this need for threatened taxa and to quantify the need for further action and effective alleviation of threats. These metrics (research need, research achievement, management need, management achievement, and percent threat reduction) can be aggregated to examine trends for an individual taxon or for threats across multiple taxa. We tested the utility of these metrics by applying them to Australian threatened birds, which appears to be the first time that progress in research and management of threats has been assessed for all threatened taxa in a faunal group at a continental scale. Some research has been conducted on nearly three-quarters of known threats to taxa, and there is a clear understanding of how to alleviate nearly half of the threats with the highest impact. Some management has been attempted on nearly half the threats. Management outcomes ranged from successful trials to complete mitigation of the threat, including for one-third of high-impact threats. Progress in both research and management tended to be greater for taxa that were monitored or occurred on oceanic islands. Predation by cats had the highest potential threat score. However, there has been some success reducing the impact of cat predation, so climate change (particularly drought), now poses the greatest threat to Australian threatened birds. Our results demonstrate the potential for the proposed metrics to encapsulate the major trends in research and management of both threats and threatened taxa and provide a basis for international comparisons of evidence-based conservation science.

Individual islet respirometry reveals functional diversity within the islet population of mice and human donors

OBJECTIVE

Islets from the same pancreas show remarkable variability in glucose sensitivity. While mitochondrial respiration is essential for glucose-stimulated insulin secretion, little is known regarding heterogeneity in mitochondrial function at the individual islet level. This is due in part to a lack of high-throughput and non-invasive methods for detecting single islet function.

METHODS

We have developed a novel non-invasive, high-throughput methodology capable of assessing mitochondrial respiration in large-sized individual islets using the XF96 analyzer (Agilent Technologies).

RESULTS

By increasing measurement sensitivity, we have reduced the minimal size of mouse and human islets needed to assess mitochondrial respiration to single large islets of >35,000 μm2 area (∼210 μm diameter). In addition, we have measured heterogeneous glucose-stimulated mitochondrial respiration among individual human and mouse islets from the same pancreas, allowing population analyses of islet mitochondrial function for the first time.

CONCLUSIONS

We have developed a novel methodology capable of analyzing mitochondrial function in large-sized individual islets. By highlighting islet functional heterogeneity, we hope this methodology can significantly advance islet research.

Neonatal outcomes of elective early-term births after demonstrated fetal lung maturity

BACKGROUND

Studies of early-term birth after demonstrated fetal lung maturity show that respiratory and other outcomes are worse with early-term birth (37⁰-38⁶ weeks) even after demonstrated fetal lung maturity when compared with full-term birth (39⁰-40⁶ weeks). However, these studies included medically indicated births and are therefore potentially limited by confounding by the indication for delivery. Thus, the increase in adverse outcomes might be due to the indication for early-term birth rather than the early-term birth itself.

OBJECTIVE

We examined the prevalence and risks of adverse neonatal outcomes associated with early-term birth after confirmed fetal lung maturity as compared with full-term birth in the absence of indications for early delivery.

STUDY DESIGN

This is a secondary analysis of an observational study of births to 115,502 women in 25 hospitals in the United States from 2008 through 2011. Singleton nonanomalous births at 37-40 weeks with no identifiable indication for delivery were included; early-term births after positive fetal lung maturity testing were compared with full-term births. The primary outcome was a composite of death, ventilator for ≥2 days, continuous positive airway pressure, proven sepsis, pneumonia or meningitis, treated hypoglycemia, hyperbilirubinemia (phototherapy), and 5-minute Apgar <7. Logistic regression and propensity score matching (both 1:1 and 1:2) were used.

RESULTS

In all, 48,137 births met inclusion criteria; the prevalence of fetal lung maturity testing in the absence of medical or obstetric indications for early delivery was 0.52% (n = 249). There were 180 (0.37%) early-term births after confirmed pulmonary maturity and 47,957 full-term births. Women in the former group were more likely to be non-Hispanic white, smoke, have received antenatal steroids, have induction, and have a cesarean. Risks of the composite (16.1% vs 5.4%; adjusted odds ratio, 3.2; 95% confidence interval, 2.1-4.8 from logistic regression) were more frequent with elective early-term birth. Propensity scores matching confirmed the increased primary composite in elective early-term births: adjusted odds ratios, 4.3 (95% confidence interval, 1.8-10.5) for 1:1 and 3.5 (95% confidence interval, 1.8-6.5) for 1:2 matching. Among components of the primary outcome, CPAP use and hyperbilirubinemia requiring phototherapy were significantly increased. Transient tachypnea of the newborn, neonatal intensive care unit admission, and prolonged neonatal intensive care unit stay (>2 days) were also increased with early-term birth.

CONCLUSION

Even with confirmed pulmonary maturity, early-term birth in the absence of medical or obstetric indications is associated with worse neonatal respiratory and hepatic outcomes compared with full-term birth, suggesting relative immaturity of these organ systems in early-term births.

X-ray and Ultrasound Localization of Non-Palpable Breast Lesions and Difficulties in Management

Seventy-four patients who have had biopsy of a non-palpable breast lesion are reviewed. A double-dye localization technique was used in 88% while in 12% localization of the lesion was best achieved by ultrasound mammography. Biopsy was successful in 70 patients (95%) at the first attempt. The overall incidence of malignancy was 20%, being greater in asymptomatic patients (32%) than in patients with mastalagia (16%). Re-excision of the biopsy site in these patients showed residual cancer in 33%. It is suggested that both careful examination of the operative specimen and postoperative mammography may be necessary to ensure that the original lesion has been removed. Re-excision of the biopsy site appears to be necessary when the histology is malignant.

Recalling and Intending to Enact Health Recommendations: Optimal Number of Prescribed Behaviors in Multibehavior Messages

Two experiments investigated the effects of the number of health recommendations (e.g., quit smoking; relax for a day) contained in a health-promotion message on recommendation recall and intentions to enact the recommendations. We hypothesized that if recommendations are stored individually, a higher number of presented recommendations will increase the number of recalled recommendations. As the number of recommendations increases, however, recipients are likely to summarize more recommendations as part of a single, more general theme (or header), resulting in a decrease in the proportion of recalled recommendations. Two experiments (N = 193 and N = 266) found that the total number of recalled recommendations increased and the proportion of recalled recommendations decreased with the number of presented recommendations. Experiment 2 replicated the findings with the number and the proportion of intended behaviors. The implications of these findings for future behavioral health interventions are discussed.

Imaging of Solid Kidney Tumours in Children

Eighteen children aged 6 months to 12 years with 20 solid renal tumours; 13 Wilms' tumours (WT), 2 clear cell sarcomas of the kidney, 1 malignant rhabdoid tumour of the kidney and 2 cases of bilateral nephroblastomatosis with Wilms' tumour underwent evaluation with US, CT and MR imaging. Contrast-enhanced CT and non-enhanced MR were equally accurate in determining the size and origin of the tumour but were unreliable in separation of stages I, II and III. US could only accurately assess the size of the tumours. MR characteristics varied somewhat between WTs and non-WTs but contrast-enhanced MR imaging might be useful for separation of WTs from nephroblastomatosis.

Preterm neonatal morbidity and mortality by gestational age: a contemporary cohort

BACKGROUND

Although preterm birth <37 weeks' gestation is the leading cause of neonatal morbidity and mortality in the United States, the majority of data regarding preterm neonatal outcomes come from older studies, and many reports have been limited to only very preterm neonates. Delineation of neonatal outcomes by delivery gestational age is needed to further clarify the continuum of mortality and morbidity frequencies among preterm neonates.

OBJECTIVE

We sought to describe the contemporary frequencies of neonatal death, neonatal morbidities, and neonatal length of stay across the spectrum of preterm gestational ages.

STUDY DESIGN

This was a secondary analysis of an obstetric cohort of 115,502 women and their neonates who were born in 25 hospitals nationwide, 2008 through 2011. All liveborn nonanomalous singleton preterm (23.0-36.9 weeks of gestation) neonates were included in this analysis. The frequency of neonatal death, major neonatal morbidity (intraventricular hemorrhage grade III/IV, seizures, hypoxic-ischemic encephalopathy, necrotizing enterocolitis stage II/III, bronchopulmonary dysplasia, persistent pulmonary hypertension), and minor neonatal morbidity (hypotension requiring treatment, intraventricular hemorrhage grade I/II, necrotizing enterocolitis stage I, respiratory distress syndrome, hyperbilirubinemia requiring treatment) were calculated by delivery gestational age; each neonate was classified once by the worst outcome for which criteria was met.

RESULTS

In all, 8334 deliveries met inclusion criteria. There were 119 (1.4%) neonatal deaths. In all, 657 (7.9%) neonates had major morbidity, 3136 (37.6%) had minor morbidity, and 4422 (53.1%) survived without any of the studied morbidities. Deaths declined rapidly with each advancing week of gestation. This decline in death was accompanied by an increase in major neonatal morbidity, which peaked at 54.8% at 25 weeks of gestation. As frequencies of death and major neonatal morbidity fell, minor neonatal morbidity increased, peaking at 81.7% at 31 weeks of gestation. The frequency of all morbidities fell >32 weeks. After 25 weeks, neonatal length of hospital stay decreased significantly with each additional completed week of pregnancy; among babies delivered from 26-32 weeks of gestation, each additional week in utero reduced the subsequent length of neonatal hospitalization by a minimum of 8 days. The median postmenstrual age at discharge nadired around 36 weeks' postmenstrual age for babies born at 31-35 weeks of gestation.

CONCLUSION

Our data show that there is a continuum of outcomes, with each additional week of gestation conferring survival benefit while reducing the length of initial hospitalization. These contemporary data can be useful for patient counseling regarding preterm outcomes.

Nonmedically indicated induction vs expectant treatment in term nulliparous women

OBJECTIVE

The purpose of this study was to compare maternal and neonatal outcomes in nulliparous women with nonmedically indicated inductions at term vs those expectantly treated.

STUDY DESIGN

Data were obtained from maternal and neonatal charts for all deliveries on randomly selected days across 25 US hospitals over a 3-year period. A low-risk subset of nulliparous women with vertex nonanomalous singleton gestations who delivered 38 0/7 to 41 6/7 weeks were selected. Maternal and neonatal outcomes for nonmedically indicated induction within each week were compared with women who did not undergo nonmedically indicated induction during that week. Multivariable analysis was used to adjust for hospital, maternal age, race/ethnicity, body mass index, cigarette use, and insurance status.

RESULTS

We found 31,169 women who met our criteria. Neonatal complications were either less frequent with nonmedically indicated induction or no different between groups. Nonmedically indicated induction was associated with less frequent peripartum infections (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.16-0.98) at 38 weeks of gestation and less frequent third- and fourth-degree lacerations (OR, 0.60; 95% CI, 0.42-0.86) and less frequent peripartum infections (OR, 0.66; 95% CI, 0.49-0.90) at 39 weeks of gestation. Nonmedically indicated induction was associated with a longer admission-to-delivery time by approximately 3-4 hours and increased odds of cesarean delivery at 38 (OR, 1.50; 95% CI, 1.08-2.08) and 40 weeks (OR, 1.30; 95% CI, 1.15-1.46) of gestation.

CONCLUSION

At 39 weeks of gestation, nonmedically indicated induction is associated with lower maternal and neonatal morbidity than women who are expectantly treated.

Summary of recommendations for the diagnosis and treatment of malaria by the Committee to Advise on Tropical Medicine and Travel (CATMAT)

BACKGROUND

On behalf of the Public Health Agency of Canada, the Committee to Advise on Tropical Medicine and Travel (CATMAT) developed the Canadian Recommendations for the Prevention and Treatment of Malaria Among International Travellers for Canadian health care providers who are preparing patients for travel to malaria-endemic areas and treating travellers who have returned ill. These recommendations aim to achieve appropriate diagnosis and management of malaria, a disease that is still uncommon in Canada.

OBJECTIVE

To provide recommendations on the appropriate diagnosis and treatment of malaria.

METHODS

CATMAT reviewed all major sources of information on malaria diagnosis and treatment, as well as recent research and national and international epidemiological data, to tailor guidelines to the Canadian context. The evidence-based medicine recommendations were developed with associated rating scales for the strength and quality of the evidence.

RECOMMENDATIONS

Malarial management depends on rapid identification of the disease, as well as identification of the malaria species and level of parasitemia. Microscopic identification of blood samples is both rapid and accurate but can be done only by trained laboratory technicians. Rapid diagnostic tests are widely available, are simple to use and do not require specialized laboratory equipment or training; however, they do not provide the level of parasitemia and do require verification. Polymerase chain reaction (PCR), although still limited in availability, is emerging as the gold standard for high sensitivity and specificity in identifying the species.

The effects of olanzapine on genome-wide DNA methylation in the hippocampus and cerebellum

Background

The mechanism of action of olanzapine in treating schizophrenia is not clear. This research reports the effects of a therapeutic equivalent treatment of olanzapine on DNA methylation in a rat model in vivo.

Genome-wide DNA methylation was assessed using a MeDIP-chip analysis. All methylated DNA immunoprecipitation (MeDIP), sample labelling, hybridization and processing were performed by Arraystar Inc (Rockville, MD, USA). The identified gene promoters showing significant alterations to DNA methylation were then subjected to Ingenuity Pathway Analysis (Ingenuity System Inc, CA, USA).

Results

The results show that olanzapine causes an increase in methylation in 1,140, 1,294 and 1,313 genes and a decrease in methylation in 633, 565 and 532 genes in the hippocampus, cerebellum and liver, respectively. Most genes affected are tissue specific. Only 41 affected genes (approximately 3%) showed an increase and no gene showed a decrease in methylation in all three tissues. Further, the two brain regions shared 123 affected genes (approximately 10%). The affected genes are enriched in pathways affecting dopamine signalling, molecular transport, nervous system development and functions in the hippocampus; ephrin receptor signalling and synaptic long-term potentiation in the cerebellum; and tissue morphology, cellular assembly and organization in the liver. Also, the affected genes included those previously implicated in psychosis.

Conclusions

The known functions of affected genes suggest that the observed epigenetic changes may underlie the amelioration of symptoms as well as accounting for certain adverse effects including the metabolic syndrome. The results give insights into the mechanism of action of olanzapine, therapeutic effects and the side effects of antipsychotics.

De-epithelialized fasciocutaneous turnover flap for recurrent calcaneal wound with osteomyelitis

Recurrent ulcerations of the foot and ankle almost always present a challenge to lower extremity surgeons. Recalcitrant heel ulcerations with osteomyelitis are especially difficult to treat because of the lack of soft tissue coverage. The turnover flap is a simple, fast, and effective treatment method for lower extremity wounds. It is a de-epithelialized fasciocutaneous flap harvested from the adjacent area of the wound. We believe it is an underused technique for advanced wound closure in the lower extremity. It offers several advantages compared with traditional, more difficult to perform, flaps. We have seen an excellent result 18 months after using the turnover flap in a patient with recurrent posterior heel ulceration with calcaneal osteomyelitis.

Outcomes in critical care delivery at Jimma University Specialised Hospital, Ethiopia

The aim of this study was to assess outcomes following intensive care unit (ICU) admissions at Jimma University Specialised Hospital, Ethiopia. This was a retrospective observational study. Data were collected regarding all ICU admissions and discharges during a 12-month period beginning August 2011. Demographic data and information regarding diagnosis, length-of-stay and outcome were gathered and data analysed. There were 370 admissions to the ICU during the study period. Median age (interquartile range) was 32.0 (22.0-47.0) years and 56.2% were males. The median length-of-stay (interquartile range) was 3.0 (1.0-7.0) days. The overall ICU mortality rate was 50.4% and major causes included trauma, cardiac disease, acute abdominal presentations, septic shock, tetanus and hysterectomy secondary to uterine rupture. Medical diagnoses accounted for 50.1% of admissions followed by surgery (43.2%) and obstetrics (5.8%). Corresponding mortality rates were 53.6, 48.0 and 42.9%, respectively. The main cause for surgical admission was trauma, with head injury carrying a mortality of 52.1%. The principal cause for medical admission was cardiac disease. In children, trauma, upper airway obstruction and communicable diseases were most common. Critical care mortality rates at this Ethiopian university hospital reflect the challenges facing critical care delivery in the developing world. Delayed presentation to hospital secondary to poor access to healthcare plays a predominant role. This is confounded by inadequate staffing, training, diagnostic and interventional limitations. Despite resource restraints, simple cost-effective measures may improve morbidity and mortality.

Corticosteroids in the Treatment of Pseudomembranous Colitis: A Report of 3 Cases

Clostridium difficile associated diarrhoea has been an increasing problem in the last decade in the UK and is a cause of significant morbidity. At the most severe end of the spectrum it causes pseudomembranous colitis which has a significant associated mortality rate and can be refractory to standard treatments. Here we present three cases of proven pseudomembranous colitis in which systemic corticosteroids were used as an adjunct to treatment, raising the possibility of a new treatment option for this difficult condition.

Melanocortin-3 receptors are involved in adaptation to restricted feeding

The central nervous melanocortin system forms a neural network that maintains energy homeostasis. Actions involving neural melanocortin-3 receptors (MC3Rs) regulate the expression rhythms in ingestive behaviors and metabolism anticipating nutrient intake. Here, we characterized the response of Mc3r knockout (Mc3r(-/-)) and wild type (WT) mice to a restricted feeding (RF) schedule where food access was limited to a 4-h period mid light cycle using a mechanical barrier. Mc3r(-/-) mice adapted poorly to the food restriction schedule. Anticipatory activity and the initial bout of intense feeding activity associated with granting food access were attenuated in Mc3r(-/-) mice, resulting in increased weight loss relative to controls. To investigate whether activity in specific hypothalamic nuclei contribute to the Mc3r(-/-) phenotype observed, we assessed hypothalamic FOS-immunoreactivity (FOS-IR) associated with food restriction. Food access markedly increased FOS-IR in the dorsomedial hypothalamus (DMH), but not in the suprachiasmatic or ventromedial hypothalamic nuclei (SCN and VMN, respectively) compared to ad libitum fed mice. Mc3r(-/-) mice displayed a significant reduction in FOS-IR in the DMH during feeding. Analysis of MC3R signaling in vitro indicated dose-dependent stimulation of the extracellular signal-regulated kinase (ERK) pathway by the MC3R agonist d-Trp(8)-γMSH. Treatment of WT mice with d-Trp(8)-γMSH administered intracerebroventricularly increased the number of pERK neurons 1.7-fold in the DMH. These observations provide further support for the involvement of the MC3Rs in regulating adaptation to food restriction. Moreover, MC3Rs may modulate the activity of neurons in the DMH, a region previously linked to the expression of the anticipatory response to RF.

Estimating sediment and caesium-137 fluxes in the Ribble Estuary through time-series airborne remote sensing

High spatial and temporal resolution airborne imagery were acquired for the Ribble Estuary, North West England in 1997 and 2003, to assess the application of time-series airborne remote sensing to quantify total suspended sediment and radionuclide fluxes during a flood and ebb tide sequence. Concomitant measurements of suspended particulate matter (SPM) and water column turbidity were obtained during the time-series image acquisition for the flood and ebb tide sequence on the 17th July 2003 to verify the assumption of a vertically well mixed estuary and thus justifying the vertical extrapolation of spatially integrated estimate of surface SPM. The ¹³⁷Cs activity concentrations were calculated from a relatively stable relationship between SPM and ¹³⁷Cs for the Ribble Estuary. Total estuary wide budgets of sediment and ¹³⁷Cs were obtained by combining the image-derived estimates of surface SPM and ¹³⁷Cs with estimates of water volume from a two-dimensional hydrodynamic model (VERSE) developed for the Ribble Estuary. These indicate that around 10,000 tons of sediment and 2.72 GBq of ¹³⁷Cs were deposited over the tidal sequence monitored in July 2003. This compared favourably with bed height elevation change estimated from field work. An uncertainty analysis on the total sediment and ¹³⁷Cs flux yielded a total budget of the order of 40% on the final estimate. The results represent a novel approach to providing a spatially integrated estimate of the total net sediment and radionuclide flux in an intertidal environment over a flood and ebb tide sequence.

Exposure of birds to radionuclides and other contaminants in Special Protection Areas (SPAs) in North-West England

There has been a decline in the population of some bird species at Morecambe Bay and the Solway Firth Special Protected Areas in North-West England during the last fifty years. It was suggested that the declines were caused, in part, by contaminants in the food and environment, primarily from the radioactive effluent discharge from the Sellafield Ltd nuclear fuel reprocessing plant in Cumbria. This study analysed bird feathers and tissues, vegetation and sediment for radionuclides, metals and persistent organic compounds. The non-radionuclide results were all low compared to relevant action limits. The ERICA model was used with field data to estimate the radiological dose to birds from exposure to (137)Cs and (241)Am with results between 1.26 to 3.83 microGy h(-1), below the ERICA screening level of 10 microGy h(-1) and within the IAEA 40 microGy h(-1) guideline value below which potential adverse impacts on biota are unlikely. The study showed no link between bird population decline and anthropogenic discharges to the SPAs.

Modelling radioactivity in the Irish Sea: from discharge to dose

In order to support authorised discharges of low level radioactive liquid effluent into coastal regions, mathematical models are required to robustly predict radiological impacts on critical groups of current and proposed changes to liquid discharges. The grid model presented here simulates the long term dispersion and transport of radioactivity discharged from the Sellafield site in Cumbria, UK, and the subsequent exposure of critical groups in Cumbria and across the Irish Sea in Northern Ireland. The fine grid of the model allows a good resolution of the seabed sediment distribution. This benefits the predictions for the last decades of low discharge level, when bed sediment can become a source of contamination by bringing back the legacy of past high discharges. This is highlighted by the dose comparison, where the predicted dose to Cumbria critical group follows well the dose estimated from environmental data during the low discharge level period.

An approach for the assessment of risk from chronic radiation to populations of phytoplankton and zooplankton

A conceptual model of the effects of chronic radiation on a population of phytoplankton and zooplankton in an oceanic nutrient layer is presented. The model shows that there are distinct threshold dose rates at which the different plankton populations become unsustainable. These are 10,400 microGy h(-1) for phytoplankton and 125 microGy h(-1) for zooplankton. Both these values are considerably greater than the current screening values for protection of 10 microGy h(-1). The model highlights the effects of predator-prey dynamics in predicting that when the zooplankton is affected by the radiation dose, the phytoplankton population can increase. In addition, the model was altered to replicate the dose rates to the plankton of a previous ERICA Irish Sea assessment (24 microGy h(-1) for zooplankton and 430 microGy h(-1) to phytoplankton). The results showed only a 10% decrease in the zooplankton population and a 15% increase in the phytoplankton population. Therefore, at this level of dose, the model predicts that although the dose rate exceeds the guideline value, populations are not significantly affected. This result highlights the limitations of a single screening value for different groups of organisms.

An approach to the assessment of risk from chronic radiation to populations of European lobster, Homarus gammarus (L.)

The basic principles underlying a four-discrete age group, logistic, growth model for the European lobster Homarus gammarus are presented and discussed at proof-of-concept level. The model considers reproduction, removal by predation, natural death, fishing, radiation and migration. Non-stochastic effects of chronic low linear energy transfer (LET) radiation are modelled with emphasis on (99)Tc, using three endpoints: repairable radiation damage, impairment of reproductive ability and, at higher dose rates, mortality. An allometric approach for the calculation of LD(50/30) as a function of the mass of each life stage is used in model calibration. The model predicts that at a dose rate of 1 Gy day(-1), lobster population reproduction and survival become severely compromised, leading eventually to population extinction. At 0.01 Gy day(-1), the survival rate of an isolated population is reduced by 10%, mainly through loss of fecundity, comparable to natural migration losses. Fishing is the main ecological stress and only dose rates in the range 0.03-0.1 Gy day(-1) can achieve discernible effects above it. On the balance of radiation and other ecological stresses, a benchmark value of 0.01 Gy day(-1) is proposed for the protection of lobster populations. This value appears consistent with available information on radiation effects in wildlife.

Laboratory and field studies of polonium and plutonium in marine plankton

Uptake experiments were successfully undertaken for polonium and plutonium in the marine diatom Skeletonema costatum. Experiments were complemented with a field study which yielded concentration factors for these radionuclides for plankton samples collected in the eastern Irish Sea. The uptake experiment produced uptake half times of 0.8 and 0.6 days for plutonium and polonium, respectively. Concentration factors of 3.1 x 10(5) l kg(-1) for plutonium and 2.4 x 10(5) l kg(-1) for polonium were consistent with those suggested by the IAEA for phytoplankton. Concentration factors derived from the field study were 2 x 10(3) l kg(-1) for plutonium and 1.4 x 10(4) l kg(-1) for polonium and were more consistent with IAEA values for zooplankton rather than phytoplankton. The maximum calculated dose rate due to Po and Pu in plankton sampled in the field was 0.12 microGyh(-1). In applying the laboratory-derived phytoplankton CF values for Po and Pu, higher dose rates, in the range 6-11 microGyh(-1), were calculated. The latter values are well below the UNSCEAR and IAEA review value of 400 microGyh(-1), and are also below the Environment Agency marine action level of 40 microGyh(-1).

WITHDRAWN: Neurobehavioral effects of repeated binge toluene exposure as measured by a waiting-for-reward operant task

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An algorithm for tailoring pharmacotherapy for smoking cessation: results from a Delphi panel of international experts

BACKGROUND

Evidence-based smoking cessation guidelines recommend nicotine replacement therapy (NRT), bupropion SR and varenicline as first-line therapy in combination with behavioural interventions. However, there are limited data to guide clinicians in recommending one form over another, using combinations, or matching individual smokers to particular forms.

OBJECTIVE

To develop decision rules for clinicians to guide differential prescribing practices and tailoring of pharmacotherapy for smoking cessation.

METHODS

A Delphi approach was used to build consensus among a panel of 37 international experts from various health disciplines. Through an iterative process, panellists responded to three rounds of questionnaires. Participants identified and ranked "best practices" used by them to tailor pharmacotherapy to aid smoking cessation. An independent panel of 10 experts provided cross-validation of findings.

RESULTS

There was a 100% response rate to all three rounds. A high level of consensus was achieved in determining the most important priorities: (1) factors to consider in prescribing pharmacotherapy: evidence, patient preference, patient experience; (2) combinations based on: failed attempt with monotherapy, patients with breakthrough cravings, level of tobacco dependence; (3) specific combinations, main categories: (a) two or more forms of NRT, (b) bupropion + form of NRT; (4) specific combinations, subcategories: (1a) patch + gum, (1b) patch + inhaler, (1c) patch + lozenge; (2a) bupropion + patch, (2b) bupropion + gum; (5) impact of comorbidities on selection of pharmacotherapy: contraindications, specific pharmacotherapy useful for certain comorbidities, dual purpose medications; (6) frequency of monitoring determined by patient needs and type of pharmacotherapy.

CONCLUSION

An algorithm and guide were developed to assist clinicians in prescribing pharmacotherapy for smoking cessation. There appears to be good justification for "off-label" use such as higher doses of NRT or combination therapy in certain circumstances. This practical tool reflects best evidence to date of experts in tobacco cessation.

Head injuries in winter sports: downhill skiing, snowboarding, sledding, snowmobiling, ice skating and ice hockey

Winter sports are often associated with high speed, which carries with it the potential for collision. As such, head injuries are among the more commonly encountered injuries in winter-related sporting activities. This article focuses on popular winter sports such as downhill skiing and snowboarding, sledding, snowmobiling, ice skating, and hockey. In virtually all of these activities, the incidence and severity of head injuries can be reduced by the use of appropriate protective headgear.

Dynamic model for the assessment of radiological exposure to marine biota

A generic approach has been developed to simulate dynamically the uptake and turnover of radionuclides by marine biota. The approach incorporates a three-compartment biokinetic model based on first order linear kinetics, with interchange rates between the organism and its surrounding environment. Model rate constants are deduced as a function of known parameters: biological half-lives of elimination, concentration factors and a sample point of the retention curve, allowing for the representation of multi-component release. The new methodology has been tested and validated in respect of non-dynamic assessment models developed for regulatory purposes. The approach has also been successfully tested against research dynamic models developed to represent the uptake of technetium and radioiodine by lobsters and winkles. Assessments conducted on two realistic test scenarios demonstrated the importance of simulating time-dependency for ecosystems in which environmental levels of radionuclides are not in equilibrium.

Hitting Time and Inverse Problems for Markov Chains

Let Wn be a simple Markov chain on the integers. Suppose that Xn is a simple Markov chain on the integers whose transition probabilities coincide with those of Wn off a finite set. We prove that there is an M > 0 such that the Markov chain Wn and the joint distributions of the first hitting time and first hitting place of Xn started at the origin for the sets {-M, M} and {-(M + 1), (M + 1)} algorithmically determine the transition probabilities of Xn.