Contribution of local regeneration of glucocorticoids to tissue steroid pools.

11ß-Hydroxysteroid dehydrogenase 1 (11ßHSD1) is a drug target to attenuate adverse effects of chronic glucocorticoid excess. It catalyses intracellular regeneration of active glucocorticoids in tissues including brain, liver and adipose tissue (coupled to hexose-6-phosphate dehydrogenase, H6PDH). 11ßHSD1 activity in individual tissues is thought to contribute significantly to glucocorticoid levels at those sites, but its local contribution vs glucocorticoid delivery via the circulation is unknown. Here, we hypothesised that hepatic 11ßHSD1 would contribute significantly to the circulating pool. This was studied in mice with Cre-mediated disruption of Hsd11b1 in liver (Alac-Cre) vs adipose tissue (aP2-Cre) or whole-body disruption of H6pdh. Regeneration of [9,12,12-2H3]-cortisol (d3F) from [9,12,12-2H3]-cortisone (d3E), measuring 11ßHSD1 reductase activity was assessed at steady state following infusion of [9,11,12,12-2H4]-cortisol (d4F) in male mice. Concentrations of steroids in plasma and amounts in liver, adipose tissue and brain were measured using mass spectrometry interfaced with matrix-assisted laser desorption ionisation or liquid chromatography. Amounts of d3F were higher in liver, compared with brain and adipose tissue. Rates of appearance of d3F were ~6-fold slower in H6pdh-/- mice, showing the importance for whole-body 11ßHSD1 reductase activity. Disruption of liver 11ßHSD1 reduced the amounts of d3F in liver (by ~36%), without changes elsewhere. In contrast disruption of 11ßHSD1 in adipose tissue reduced rates of appearance of circulating d3F (by ~67%) and also reduced regenerated of d3F in liver and brain (both by ~30%). Thus, the contribution of hepatic 11ßHSD1 to circulating glucocorticoid levels and amounts in other tissues is less than that of adipose tissue.

The association between paramedic service system hospital offload time and response time.

OBJECTIVE: To address an important care issue in Canada, we tested the association between paramedic system hospital offload and response time, while considering the impact of other system-level factors. METHODS: Data from Calgary, Alberta (2014-2017), included median offload (exposure) and response (outcome) time aggregated by hour, with covariates paramedic system episodes of care-dispatch and arrival of a response unit-and hospital transport arrivals (collectively called volume), time of day, and season. Analyses used linear regression and modified Poisson models. RESULTS: 301,105 EMS episodes of care over 26,193 1-h periods were included. For any given 1-h period, the median (IQR) across all episodes of care for offload time, response time, episodes of care, and hospital transport arrivals were 55.3 (45.7, 66.3) min, 8.6 (7.6, 9.8) min, 12 (8, 16) episodes, and 8 (5, 10) hospital arrivals, respectively. Multivariable modelling revealed a complex association differing over levels of exposure and covariates, requiring description using "light stress" and "heavy stress" system scenarios. The light scenario was defined as median offload of 30 min and volume < 10th percentile (six episodes and four hospital arrivals), in the summer, and the heavy scenario as median offload of 90 min and volume > 90th percentile (17 episodes and 13 hospital arrivals), in the winter. An increase is reported in minutes:seconds for median hourly response time between scenarios by time of day: 1:04-4:16 (0000-0559 h.), 0:42-2:05 (0600-1159 h.), 0:57-3:01 (1200-1759 h.), and 0:18-2:21 (1800-2359 h.). CONCLUSIONS: Increasing offload is associated with increased response time; however the relationship is complex, with a greater impact on response time noted in select situations such as high volume in the winter. These observations illustrate the interdependence of paramedic, ED, and inpatient systems and provide high-yield targets for polices to mitigate the risk to community availability of paramedic resources at times of high offload delay/system stress.

ABSTRAIT: OBJECTIF: Afin de régler un problème important de soins au Canada, nous avons testé l'association entre le déchargement du système paramédical et le temps de réponse, tout en tenant compte de l'incidence d'autres facteurs au niveau du système. MéTHODES: Les données de Calgary, en Alberta (2014-2017) incluent le temps médian de déchargement (exposition) et de réponse (résultat) agrégé par heure, qui s'agit co-variables épisodes de soins du système paramédical - répartition et arrivée d'une unité d'intervention - et arrivées de transport hospitalier (collectivement appelé volume), l'heure et la saison. Les analyses ont utilisé la régression linéaire et des modèles de Poisson modifiés. RéSULTATS: 301105 épisodes de soins médicaux d'urgence sur 26193 périodes d'une heure ont été inclus. Pour une période d'une heure donnée, la médiane (QRI) pour tous les épisodes de soins pour le temps de déchargement, le temps de réponse, les épisodes de soins et les arrivées par transport à l'hôpital était de 55,3 (45,7, 66,3) minutes, 8,6 (7,6, 9,8) minutes, 12 (8, 16) épisodes et 8 (5, 10) arrivées à l'hôpital, respectivement. La modélisation multi-variable a révélé une association complexe qui varie selon les niveaux d'exposition et les co-variables, et qui nécessite une description à l'aide de scénarios de systèmes de « stress léger ¼ et de « stress lourd ¼. Le scénario léger a été défini comme un déchargement médian de 30 minutes, volume inférieur au 10e percentile (six épisodes et quatre arrivées à l'hôpital), pendant l'été. Le scénario lourd comme déchargement médian de 90 minutes, volume > 90e percentile (17 épisodes et 13 arrivées à l'hôpital), en hiver. Une augmentation est rapportée en minutes: secondes pour le temps de réponse horaire médian entre des scénarios par heure du jour : 1:04-4:16 (0000-0559 h.), 0:42-2:05 (0600-1159 h.), 0:57-3:01 (1200-1759 h.), et 0:18-2:21 (1800-2359 h.). CONCLUSIONS: L'augmentation du déchargement est associée à une augmentation du temps de réponse, mais la relation est complexe, avec un impact plus important sur le temps de réponse noté dans certaines situations, comme un volume élevé en hiver. Ces observations illustrent l'interdépendance des systèmes paramédicaux, des services d'urgence et des services aux patients hospitalisés et fournissent des cibles à haut rendement pour les politiques afin d'atténuer le risque pour la disponibilité des ressources paramédicales dans la collectivité en période de retard élevé ou de stress systémique.

Health service utilization by people experiencing homelessness and engaging with community paramedics: a pre-post study.

OBJECTIVES: To compare health service utilization of patients interacting with a mobile integrated health care program consisting of advanced care paramedics delivering community paramedic care to people experiencing homelessness before and after their initial visit. METHODS: ED visits, physician claims, and pharmaceutical dispensations were compared in the year prior to and in the year following the initial community paramedic visit. Administrative databases were linked and utilization rates were calculated and analyzed between periods in this pre-post cohort study. RESULTS: The 1360 community paramedic patients included in this study had no significant change in ED visits (IRR: 1.02) following their initial visit. There were 17,699 ED visits in the pre-period and 18,398 visits in the post-period. There was an observed increase in rates of primary care physician claims (IRR 1.22) and pharmaceutical dispensations from community pharmacies (IRR 1.04). Patients who did not have pharmaceutical dispensations and those without physician claims in the pre-period were significantly less likely to not access these services in the post-period. CONCLUSIONS: In the year following the initial community paramedic visit there were small but significant increases in community-based care utilization of people experiencing homelessness. These data suggest that the continued development and implementation of paramedics as part of an interdisciplinary care team can increase access to care for a traditionally underserved population with complex health needs. Patients would likely benefit from the integration of community paramedics in community-based management that aim to improve access to care following ED visits.

RéSUMé: OBJECTIFS: Comparer l'utilisation des services de santé des patients interagissant avec un programme de soins de santé mobile intégrés composé d'ambulanciers paramédicaux de soins avancés fournissant des soins paramédicaux communautaires aux personnes sans domicile fixe avant et après leur visite initiale. MéTHODES: Les visites aux urgences, les demandes de remboursement des médecins et les prescriptions pharmaceutiques ont été comparées dans l'année précédant et dans l'année suivant la visite initiale du personnel paramédical communautaire. Les bases de données administratives ont été reliées, et les taux d'utilisation ont été calculés et analysés entre les périodes dans cette étude de cohorte avant et après. RéSULTATS: Les 1 360 patients paramédicaux communautaires inclus dans cette étude n'ont pas connu de changement significatif dans les visites aux urgences (IRR : 1,02) après leur visite initiale. Il y a eu 17 699 visites aux urgences dans la pré-période et 18 398 visites dans la post-période. On a observé une augmentation des taux de demandes de remboursement des médecins de soins primaires (IRR : 1,22) et des dispensations de produits pharmaceutiques par les pharmacies communautaires (IRR : 1,04). Les patients qui n'ont pas bénéficié d'une dispensation de produits pharmaceutiques et ceux qui n'ont pas fait l'objet d'une demande de remboursement par un médecin au cours de la période précédente étaient significativement moins susceptibles de ne pas avoir accès à ces services au cours de la période suivante. CONCLUSIONS: Au cours de l'année qui a suivi la première visite du personnel paramédical communautaire, on a constaté une augmentation faible mais significative de l'utilisation des soins communautaires par les personnes sans domicile. Ces données suggèrent que le développement et la mise en œuvre continus des ambulanciers paramédicaux au sein d'une équipe de soins interdisciplinaire peuvent accroître l'accès aux soins pour une population traditionnellement mal desservie et présentant des besoins de santé complexes. Les patients bénéficieraient probablement de l'intégration des ambulanciers communautaires dans la gestion communautaire qui vise à améliorer l'accès aux soins après une visite aux urgences.

Linkage of Emergency Medical Services and Hospital Data: A Necessary Precursor to Improve Understanding of Outcomes of Prehospital Care.

Objective: Linking emergency medical services (EMS) data to hospital outcomes is important for quality assurance and research initiatives. However, non-linkage due to missing or incomplete patient information may increase the risk of bias and distort findings. The purpose of this study was to explore if an optimization strategy, in addition to an existing linkage process, improved the linkage rate and reduced selection and information bias. Methods: 4,150 transported patients in a metropolitan EMS system in Alberta, Canada from 2016/17 were linked to two Emergency Department (ED) databases by a standard strategy using a unique health care number, date/time of ED arrival, and hospital name. An optimized strategy added additional linkage steps incorporating last name, year of birth, and a manual search. The strategies were compared to assess the rate of linkage, and to describe event and patient-level characteristics of unlinked records. Results: The standard strategy resulted in 3,650 out of 4,150 (88.0%) linked records (95% CI 86.9%-88.9%). Of the 500 non-linked records, an additional 381 were linked by the optimized strategy (n = 4,031/4,150 [97.1%; 95% CI: 96.6%-97.6%]). There were no false positive linkages. The highest linkage failure was in 25 to 34 year-old patients (n = 93/478, 19.5%), males (n = 236/1975, 12.0%), Echo level events (n = 15/77, 19.5%), and emergency transport (45/231, 19.5%). The optimized strategy improved linkage in these groups by 68.8% (64/93), 79.2% (187/236), 40.0% (6/15), and 51.1% (23/45) respectively. For dispatch card, the highest linkage failure occurred in Card 24-Pregnancy/Childbirth/Miscarriage (n = 30/44, 68.2%), Card 27-Stab/Gunshot/Penetrating Trauma (n = 6/17, 35.3%), and Card 9-Cardiac/Respiratory Arrest/Death (n = 12/46, 26.1%). The optimized strategy improved linkage by 10.0% (3/30), 83.3% (5/6), and 41.7% (5/12) respectively. For the 119 unlinked records, 71 (59.7%) had sufficient information for linkage, but no appropriately matching records could be found. Conclusion: An optimized sequential deterministic strategy linking EMS data to ED outcomes improved the linkage rate without increasing the number of false positive links, and reduced the potential for bias. Even with adequate information, some records were not linked to their ED visit. This study underscores the importance of understanding how data are linked to hospital outcomes in EMS research and the potential for bias.

11ß-HSD1 plays a critical role in trabecular bone loss associated with systemic glucocorticoid therapy.

BACKGROUND: Despite their efficacy in the treatment of chronic inflammation, the prolonged application of therapeutic glucocorticoids (GCs) is limited by significant systemic side effects including glucocorticoid-induced osteoporosis (GIOP). 11ß-Hydroxysteroid dehydrogenase type 1 (11ß-HSD1) is a bi-directional enzyme that primarily activates GCs in vivo, regulating tissue-specific exposure to active GC. We aimed to determine the contribution of 11ß-HSD1 to GIOP. METHODS: Wild type (WT) and 11ß-HSD1 knockout (KO) mice were treated with corticosterone (100 µg/ml, 0.66% ethanol) or vehicle (0.66% ethanol) in drinking water over 4 weeks (six animals per group). Bone parameters were assessed by micro-CT, sub-micron absorption tomography and serum markers of bone metabolism. Osteoblast and osteoclast gene expression was assessed by quantitative RT-PCR. RESULTS: Wild type mice receiving corticosterone developed marked trabecular bone loss with reduced bone volume to tissue volume (BV/TV), trabecular thickness (Tb.Th) and trabecular number (Tb.N). Histomorphometric analysis revealed a dramatic reduction in osteoblast numbers. This was matched by a significant reduction in the serum marker of osteoblast bone formation P1NP and gene expression of the osteoblast markers Alp and Bglap. In contrast, 11ß-HSD1 KO mice receiving corticosterone demonstrated almost complete protection from trabecular bone loss, with partial protection from the decrease in osteoblast numbers and markers of bone formation relative to WT counterparts receiving corticosterone. CONCLUSIONS: This study demonstrates that 11ß-HSD1 plays a critical role in GIOP, mediating GC suppression of anabolic bone formation and reduced bone volume secondary to a decrease in osteoblast numbers. This raises the intriguing possibility that therapeutic inhibitors of 11ß-HSD1 may be effective in preventing GIOP in patients receiving therapeutic steroids.

The effectiveness of prehospital hypertonic saline for hypotensive trauma patients: a systematic review and meta-analysis.

BACKGROUND: The optimal prehospital fluid for the treatment of hypotension is unknown. Hypertonic fluids may increase circulatory volume and mute the pro-inflammatory response of the body to injury and illness. The purpose of this systematic review is to determine whether in patients presenting with hypotension in the prehospital setting (population), the administration of hypertonic saline (intervention), compared to an isotonic fluid (control), improves survival to hospital discharge (outcome). METHODS: Searches were conducted in Medline, Embase, CINAHL, and CENTRAL from the date of database inception to November, 2016, and included all languages. Two reviewers independently selected randomized control trials of hypotensive human participants administered hypertonic saline in the prehospital setting. The comparison was isotonic fluid, which included normal saline, and near isotonic fluids such as Ringer's Lactate. Assessment of study quality was done using the Cochrane Collaborations' risk of bias tool and a fixed effect meta-analysis was conducted to determine the pooled relative risk of survival to hospital discharge. Secondary outcomes were reported for fluid requirements, multi-organ failure, adverse events, length of hospital stay, long term survival and disability. RESULTS: Of the 1160 non-duplicate citations screened, thirty-eight articles underwent full-text review, and five trials were included in the systematic review. All studies administered a fixed 250 ml dose of 7.5% hypertonic saline, except one that administered 300 ml. Two studies used normal saline, two Ringer's Lactate, and one Ringer's Acetate as control. Routine care co-interventions included isotonic fluids and colloids. Five studies were included in the meta-analysis (n = 1162 injured patients) with minimal statistical heterogeneity (I 2  = 0%). The pooled relative risk of survival to hospital discharge with hypertonic saline was 1.02 times that of patients who received isotonic fluids (95% Confidence Interval: 0.95, 1.10). There were no consistent statistically significant differences in secondary outcomes. CONCLUSIONS: There was no significant difference in important clinical outcomes for hypotensive injured patients administered hypertonic saline compared to isotonic fluid in the prehospital setting. Hypertonic saline cannot be recommended for use in prehospital clinical practice for the management of hypotensive injured patients based on the available data. PROSPERO registration # CRD42016053385 .

Dynamics of the "popcorn" Wolbachia infection in outbred Aedes aegypti informs prospects for mosquito vector control.

Forty percent of the world's population is at risk of contracting dengue virus, which produces dengue fever with a potentially fatal hemorrhagic form. The wMelPop Wolbachia infection of Drosophila melanogaster reduces life span and interferes with viral transmission when introduced into the mosquito Aedes aegypti, the primary vector of dengue virus. Wolbachia has been proposed as an agent for preventing transmission of dengue virus. Population invasion by Wolbachia depends on levels of cytoplasmic incompatibility, fitness effects, and maternal transmission. Here we characterized these traits in an outbred genetic background of a potential target population of Ae. aegypti using two crossing schemes. Cytoplasmic incompatibility was strong in this background, and the maternal transmission rate of Wolbachia was high. The infection substantially reduced longevity of infected adult females, regardless of whether adults came from larvae cultured under high or low levels of nutrition or density. The infection reduced the viability of diapausing and nondiapausing eggs. Viability was particularly low when eggs were laid by older females and when diapausing eggs had been stored for a few weeks. The infection affected mosquito larval development time and adult body size under different larval nutrition levels and densities. The results were used to assess the potential for wMelPop-CLA to invade natural populations of Ae. aegypti and to develop recommendations for the maintenance of fitness in infected mosquitoes that need to compete against field insects.

Characterising transmission of a tuberculosis genotype in Scotland: a qualitative approach to social network enquiry.

SETTING: Contact investigation resulting from specimens sent to the Scottish Mycobacteria Reference Laboratory. OBJECTIVE: To characterise patients and types of exposures associated with transmission of a prevalent Mycobacterium tuberculosis genotype in Scotland. DESIGN: A combined approach using molecular epidemiology and semi-structured patient interviews for social network enquiry. RESULTS: We investigated social connections between 64 patients diagnosed between 1994 and 2004. Fifty-five per cent had > or = 1 identifiable contact. One third (n = 14, 32.6%) of the 43 epidemiological links detected were discerned as a result of patient interviews and were not previously recorded on surveillance reports, nor recognised by nurse specialists (all were non-household contacts). Sixteen putative sites of exposure were identified, 11 were public houses. Rather than a single-source outbreak, eight pockets of transmission were identified, the largest involving UK-born alcohol-misusing males frequenting several public houses. CONCLUSIONS: Using a standardised approach to explore themes around which individuals may have been exposed to TB resulted in the detection of previously unrecognised epidemiological links. Epidemiological data obtained from cluster investigations, e.g., risk and social behaviours that increase the risk of infection and sites of putative exposure, can enhance the development of more appropriate questions for the contact tracing interview.

Renal recovery after severe acute renal failure.

BACKGROUND: There is limited information about renal recovery to independence from renal replacement therapy (RRT) and about factors associated with its occurrence after severe acute renal failure (ARF). METHODS: We conducted a population-based surveillance among all adult residents of the Calgary Health Region surviving ICU admission from May 1, 1999 to April 30, 2002. The primary objective was to determine the rate of and the factors associated with 90-day survival and recovery to independence from RRT in critically ill patients with severe ARF. RESULTS: At 90 days, 96 patients (40%) were alive. Of these, 72% were RRT independent with most (87%) requiring <4 weeks to recover. Prior to RRT, the median (IQR) serum creatinine and mean (SD) serum urea were 395 (252-517) micromol/L and 29.2 (18) mmol/L, respectively. Oliguria was present in 76%. Intermittent hemodialysis was the initial modality in 46% and continuous renal replacement therapy (CRRT) in 54%. By multivariate analysis, male sex (odds ratio (OR) 7.6, 95% CI, 2.2-27, p=0.01) and a diagnosis of septic shock (OR 3.9, 95% CI 1.02-14.5, p=0.05) were associated with an increased odds of recovery. Conversely, a higher Charlson co-morbidity index score (OR 0.71, 95% CI, 0.6-0.85, p=0.04) and a higher pre-RRT serum creatinine (OR 0.20, 95% CI, 0.05-0.80, p=0.02, p=0.02) were associated with reduced odds of recovery. Chronic kidney disease or the initial modality of RRT were not associated with recovery. CONCLUSIONS: The majority of severe ARF patients who survive their acute illness are independent of RRT by 90 days. Male sex and a diagnosis of septic shock are independently associated with recovery while a greater co-morbidity score and a higher serum creatinine prior to RRT are predictive of non-recovery.

Meta-analysis of pancreaticojejunostomy versus pancreaticogastrostomy reconstruction after pancreaticoduodenectomy.

BACKGROUND: Pancreaticoduodenectomy is the primary treatment for periampullary cancer. Associated morbidity is high and often related to pancreatic anastomotic failure. This paper compares rates of pancreatic fistula, morbidity and mortality after pancreaticoduodenectomy in patients having reconstruction by pancreaticogastrostomy with those in patients having reconstruction by pancreaticojejunostomy. METHODS: A meta-analysis was performed of all large cohort and randomized controlled trials carried out since 1990. RESULTS: Eleven articles were identified for inclusion: one prospective randomized trial, two non-randomized prospective trials and eight observational cohort studies. The meta-analysis revealed a higher rate of pancreatic fistula associated with pancreaticojejunostomy reconstruction (relative risk (RR) 2.62 (95 per cent confidence interval (c.i.) 1.91 to 3.60)). A higher overall morbidity rate was also demonstrated in this group (RR 1.43 (95 per cent c.i. 1.26 to 1.61)), as was a higher mortality rate (RR 2.51 (95 per cent c.i. 1.61 to 3.91)). CONCLUSION: Current literature suggests that the safer means of pancreatic reconstruction after pancreaticoduodenectomy is pancreaticogastrostomy, but much of the evidence comes from observational cohort study data.

Bloodstream infection-associated sepsis and septic shock in critically ill adults: a population-based study.

BACKGROUND: Few studies have investigated the epidemiology of sepsis and septic shock in a large population and none have been from Canada. The objective of this study was to define the epidemiology of bloodstream infection (BSI)-associated sepsis and septic shock among all critically ill patients in a large, fully integrated health region in Canada. PATIENTS AND METHODS: All critically ill adults admitted to multidisciplinary intensive care units (ICU) in the Calgary Health Region during May 1, 1999 to April 30, 2000 were included. Clinical, microbiologic and outcome information was obtained from regional databases. RESULTS: We surveyed 1981 patients having at least one ICU admission. Systemic inflammatory response syndrome (SIRS) was diagnosed in 92%, BSI-associated sepsis (BSI with SIRS) in 6% and BSI-associated septic shock (BSI with SIRS and hypotension) in 3%; respective hospital mortality rates were 36%, 40% and 49%. The most common BSI etiologies were Staphylococcus aureus, Escherichia coli and Streptococcus species; only one isolate (1%) was highly antibiotic resistant. Independent risk factors for death among patients with SIRS included age (>or= 65), hypothermia (< 35 degrees C), and higher APACHE II and TISS scores. A surgical diagnosis was associated with decreased mortality risk. Neither a positive blood culture nor hypotension at presentation independently predicted death. CONCLUSION: Knowledge of the epidemiology of these syndromes is important for assessing the burden of disease and providing background information for investigating new therapies.

Analysis of multidrug-resistant Mycobacterium bovis from three clinical samples from Scotland.

OBJECTIVE: To determine whether multidrug-resistant (MDR) strains of Mycobacterium bovis isolated from patients in Scotland were genotypically related. DESIGN: Genotypes of MDR strains were determined using three molecular fingerprinting techniques: pulsed-field gel electrophoresis (PFGE), spoligotyping and restriction fragment length polymorphism (RFLP). PFGE profiles were also obtained for all medical and veterinary isolates occurring in Scotland in 1997-1998. RESULTS: MDR strains showed individual Dra I PFGE profiles. Case III/98 had a profile represented in both veterinary and medical populations, Case I/94 had a profile observed in medical but not veterinary isolates, and Case II/98 had a profile unique to this study. Afl II PFGE discriminated the resistant strains. Spoligotyping grouped Cases I/94 and II/98 (ST-134). Case III/98 had a spoligotype ST-140, which is commonly observed in veterinary isolates. Similarly, DRr-RFLP analysis grouped cases I/94 and II/98, whereas Case III/98 had a common veterinary profile. DRX(PGRS) RFLP gave three unique profiles. CONCLUSION: Three resistant strains were discriminated by PFGE and DRX(PGRS) RFLP, indicating that the three strains are not related in an epidemiologically relevant time scale. However, Cases I/94 and II/98 were more closely linked by spoligotyping and DRr-RFLP data. PFGE and DRr-RFLP linked Case III/98 profiles to the most common veterinary isolate.

The efficacy of the heat killing of Mycobacterium tuberculosis.

There is concern that current procedures for the heat inactivation of Mycobacterium tuberculosis may not be adequate. This raises serious safety issues for laboratory staff performing molecular investigations such as IS6110 restriction fragment length polymorphism typing. This paper confirms that the protocol of van Embden et al, as performed routinely in this laboratory, is safe and effective for the heat inactivation of M tuberculosis. This procedure involves complete immersion of a tube containing a suspension of one loopfull of growth in a water bath at 80 degrees C for 20 minutes. Seventy four isolates were included in this investigation. Despite prolonged incubation for 20 weeks, none of the heat killed M tuberculosis suspensions produced visible colonies or gave a positive growth signal from liquid culture. This method did not affect the integrity of the DNA for subsequent molecular investigations.

Molecular epidemiology of Mycobacterium malmoense infections in Scotland.

Clinical isolates of Mycobacterium malmoense collected over 5 years from patients across Scotland with a variety of diseases have been characterized by pulsed-field gel electrophoresis (PFGE), ribotyping, and 16S ribosomal DNA gene sequencing. Results indicate that this species harbors little genetic diversity and that the different strain types that were identified by PFGE showed no correlation with geographical origin or date of isolation.

Encephalopathy with staphylococcal endocarditis: multiple neuropathological findings.

BACKGROUND: Infective endocarditis is associated with serious neurological sequelae. OBJECTIVE: Here, we report a patient with Staphylococcus aureus endocarditis, secondary to congenital heart disease, with subacute onset of multiple neurological complications. RESULTS: Despite prompt antibiotic treatment with rapid sterilization of blood cultures, the patient died with brain herniation within 96 hours of admission. Neuropathological examination showed intraparenchymal hemorrhages, mycotic aneurysms, micro-abscesses and septic arteritis with accompanying infarction. Immunocytochemical studies revealed enhanced CD45 and GFAP immunoreactivity, together with adenosine A1 receptor detection on macrophages and microglia. CONCLUSIONS: Infective endocarditis is associated with multiple neuropathological lesions, which may contribute to its poor clinical outcome and activation of cells of monocyte-microglial lineage throughout the brain.

Molecular evidence for independent occurrence of IS6110 insertions at the same sites of the genome of Mycobacterium tuberculosis in different clinical isolates.

Several characteristics of Mycobacterium tuberculosis (e.g., conserved genome and low growth rate) have severely restricted the study of the microorganism. The discovery of IS6110 raised hopes of overcoming these obstacles. However, our knowledge of this IS element is relatively limited; even its two basic characteristics (transposition mechanism and target site selection) are far from well understood. In this study, IS6110 insertions in ipl loci (iplA and iplB) in two collections of clinical isolates of M. tuberculosis from different geographic locations, one from Scotland and the other from Thailand, were investigated. Five different IS6110 insertions in the loci were identified: ipl-4::IS6110, ipl-5::IS6110, ipl-11::IS6110, ipl-12::IS6110, and ipl-13::IS6110. An attempt to establish the phylogenetic relationship of the isolates containing these insertions was unsuccessful, suggesting that some of these insertions may have arisen from more than one event. This possibility is further supported by the observation that IS6110 copies existed in the same site but with different orientations in different isolates, and the insertion site of ipl-1::IS6110 harbored IS6110 copies in both iplA and iplB in different strains. All these suggest the independent occurrence of IS6110 insertions at the same sites of the genome of M. tuberculosis in different clinical isolates. The implications of this finding are discussed.

The influence of delay in closure of the abdominal wall on outcome in gastroschisis.

To evaluate the effect of a delay in closure of the abdominal wall (AWC) on outcome in the management of gastroschisis, a retrospective analysis of 91 babies admitted over a 7-year period (1992-1998) to a single neonatal surgical unit with a diagnosis of gastroschisis was carried out. Antenatal diagnosis was made in 89 (98%) cases. Surgical intervention occurred in 90 babies at a median of 4 h (standard error 0.345, range 0.5-17) post-delivery. In 72 (80%) cases primary closure of the abdominal defect was achieved, with a silo fashioned in the remaining 18 (20%). One infant died prior to AWC. The median time to full oral feeding was 22 days (2.96, 5-160), and to discharge 28 days (4.03, 11-183). There was no correlation between time to AWC and any measured outcome parameter. There was no significant difference in mortality in those patients having closure before 6 h. Thus, no correlation between time to AWC and outcome was demonstrated. This would suggest that the time taken to optimally resuscitate a newborn infant prior to surgical closure does not have an adverse influence upon outcome and is to be recommended.

Functional alpha4-integrin: a newly identified pathway of neutrophil recruitment in critically ill septic patients.

Using a novel flow chamber assay system and whole blood, we show that leukocytes from septic individuals have a four-fold elevation of adhesion, but not rolling, on a P-selectin/beta2-integrin substrate. Most leukocytes from septic patients (but not healthy controls) that bound vascular cell adhesion molecule 1 (VCAM-1) were neutrophils. All adhesion was inhibited with an antibody specific for the VCAM-1 ligand alpha4-integrin. The alpha4-integrin was present on neutrophils from septic patients but not on neutrophils from patients with localized bacterial infections. The plasma milieu of septic patients was sufficient to induce neutrophils from healthy subjects to bind VCAM-1 under flow conditions. This is the first description of alpha4-integrin/VCAM-1 pathway of neutrophil recruitment in human disease. This pathway may provide a new therapeutic target to reduce inappropriate neutrophil adhesion without altering the normal yet critical beta2-integrin-mediated adhesive function of neutrophils.

Nitric oxide synthase is absent in only a subset of cases of pyloric stenosis.

PURPOSE: The aim of this study was to study nitric oxide synthase (NOS) immunohistochemistry in the pyloric muscle and establish the role of nitric oxide in pyloric stenosis. METHODS: Pyloric muscle biopsy specimens were obtained from 20 patients with pyloric stenosis during pyloromyotomy. Ten control specimens without pyloric disease were obtained from autopsy performed less than 4 hours after death on age-matched babies who died of other causes. Tissues were fixed in 4% paraformaldehyde immediately. A monoclonal antibody against the neuronal form of NOS (bNOS) was used for immunohistochemistry. RESULTS: Immunohistochemistry showed activity of bNOS in the control specimens and some pyloric stenosis specimens. This shows that NOS is present in the pylorus in normal cases as well as in a few cases of pyloric stenosis. CONCLUSIONS: NOS deficiency leading to lack of locally available nitric oxide causes a failure of smooth muscle relaxation. This may account for the cause of pyloric stenosis in infants. However, this study shows that this is true probably only in a subset of cases. The etiology of pyloric stenosis may still be multifactorial. Further investigations are required regarding the etiology of pyloric stenosis. J Pediatr Surg 36:616-619.

The contemporary outcome of gastroschisis.

BACKGROUND: The aim of this study was to evaluate the contemporary outcome in the management of gastroschisis. METHODS: A retrospective analysis was conducted of 91 babies admitted over a 7-year period to a single neonatal surgical unit with a diagnosis of gastroschisis. RESULTS: An antenatal diagnosis was made in 89 (98%) cases. Surgical intervention occurred in 90 babies, at a mean of 5 hours (range, 0.5 to 17) postdelivery. In 72 (80%) cases, primary closure of the abdominal defect was achieved, with a silo fashioned in the remaining 18 (20%). One child died before abdominal closure. The median time to full oral feeding was 30 days (range, 5 to 160 days), and to discharge was 42 days (range, 11 to 183 days). Those children who required a silo, took longer to feed (P =.008) and stayed longer in the hospital (P =.021). The 8 (8.8%) children with an intestinal atresia, required significantly more operative procedures (P =.0001) and took significantly longer to achieve full oral feeding (P =.04), but the presence of an atresia was not an independent risk factor for mortality. There were 7 deaths (7.7%), 3 within the first 7 days. Of the deaths, 5 (71%) were caused by overwhelming sepsis. CONCLUSIONS: The contemporary mortality rate from gastroschisis is less than 8%, and minimizing septic complications would contribute significantly to reducing this. Strategies designed to improve morbidity must focus on optimizing management of those factors associated with a prolonged recovery, namely intestinal atresia, prematurity, and the use of a silo.