Prion protein N1 cleavage peptides stimulate microglial interaction with surrounding cells

Microglia act as the protective immune cell of the brain. By surveying the tissue to identify and rectify problems, they function to maintain the health of brain cells. The prion protein N-terminal cleavage fragment, N1, has demonstrated neuroprotective activities in vitro and in vivo. This study aimed to elucidate whether N1 could modulate microglial function and, if so, determine the consequences for the surrounding tissue. Using a mixed neuronal lineage and microglia co-culture system, we showed that N1 stimulation changed overall morphology and metabolism, suggesting enhanced cellular viability. Furthermore, N1 induced an increase in Cxcl10 secretion in the co-cultures. Recombinant Cxcl10, administered exogenously, mediated the changes in the mixed neuronal lineage culture morphology and metabolism in the absence of microglia, but no effect of Cxcl10 was observed on microglia cultured on their own. Direct cell-to-cell contact was required for N1 to influence microglia in the co-cultures, and this was linked with restructuring of microglial membrane composition to include a higher GM1 content at interaction sites with surrounding cells. Our findings show that N1 can play a regulatory role in microglial function in the context of an inter-connected network of cells by changing both cellular interaction sites and cytokine secretion.

Evaluation of the Assurance GDS® for Salmonella Method in Foods and Environmental Surfaces: Multilaboratory Collaborative Study

A multilaboratory collaborative study was conducted to compare the detection of Salmonella by the Assurance GDS® for Salmonella method and the Reference culture methods. Six foods, representing a variety of low microbial and high microbial load foods were analyzed. Seventeen laboratories in the United States and Canada participated in this study. No statistical differences (P < 0.05) were observed between the Assurance GDS for Salmonella and the Reference culture methods for any inoculation level of any food type or naturally contaminated food, except for pasta, for which the Assurance GDS method had a higher number of confirmed test portions for Salmonella compared to the Reference method.

Determination of Cry9C Protein in Corn-Based Foods by Enzyme-Linked Immunosorbent Assay: Interlaboratory Study

The performance of a commercially available enzyme-linked immunosorbent assay kit (Enviro-Logix) was assessed for the determination of Cry9C protein, which is produced by the genetically modified corn StarLink, in 8 types of corn-based foods (starch, refined oil, soft tortillas, tortilla chips, corn flakes, corn puffs, corn muffins, and corn bread) in an interlaboratory study involving 7 laboratories in the United States. The assay kit is a double antibody sandwich and is based on the specific interaction between antibody and antigen. The Cry9C protein analyte is sandwiched between 2 antibodies, one to capture the analyte and the other is conjugated to the enzyme, horseradish peroxidase. The enzyme uses tetramethylbenzidine/peroxide for color development. A strong acid stopping reagent is then used to change the color from blue to a stable yellow. The intensity of the color is proportional to the concentration of the Cry9C protein. In this study blind duplicates of control samples (blank material prepared from non- StarLink corn), spiked samples (blank material with the addition of Cry9C protein), and samples containing incurred analyte (products prepared with StarLink corn) were analyzed. Cry9C protein from 2 different sources was used to spike the food products. Cry9C protein produced and purified from a bacterial host was used to prepare spiked test samples at 2.72 and 6.8 ng/g. Cry9C protein from StarLink corn flour was used to prepare spiked samples at 1.97 ng/g. Average recoveries for samples spiked with corn flour Cry9C protein at 1.97 ng/g ranged from 73 to 122%, within-laboratory relative standard deviations (RSDr) ranged from 6 to 22%, and between-laboratories relative standard deviations (RSDR) ranged from 16 to 56%. Average recoveries for samples spiked with bacterial Cry9C protein at 2.72 and 6.8 ng/g ranged from 27 to 96% and from 32 to 113%, respectively; RSDr values ranged from 10 to 35%and from 7 to 38%, respectively; and the RSDR ranged from 28 to 84%and 15 to 75%, respectively. The incurred test samples were found to contain Cry9C protein at levels ranging from 0.8 to 3187 ng/g depending on the product, RSDr values ranged from 5 to 16% and RSDR values ranged from 11 to 71%. Results of the statistical analysis indicate that this method is applicable to the determination of Cry9C protein in the 8 types of collaboratively studied corn-based products containing Cry9C protein (from StarLink ) at levels of ≥2 ng/g.

Video-tube thoracostomy in trauma resuscitation: A pilot study

BACKGROUND

Complications related to incorrect positioning of tube thoracostomy (TT) have been reported to be as high as 30%. The aim of this study was to assess the feasibility of flexible videoscope guided placement of a pre-loaded chest tube, permitting direct intrapleural visualization and placement (Video-Tube Thoracostomy [V-TT]).

METHODS

A prospective, single centre, phase 1 pilot study with a parallel control group was undertaken. The population studied were adult thoracic trauma patients requiring emergency TT who were haemodynamically stable. The intervention performed was VTT. Patients in the control group underwent conventional TT. The primary outcome was tube position as defined by a consultant radiologist's interpretation of chest x-ray (CXR) or CT. The trial was registered with ANZCTR.org.au (ACTRN: 12,615,000,870,550).

RESULTS

There were 37 patients enrolled in the study - 12 patients allocated to the VTT intervention group and 25 patients allocated to conventional TT. Mean age of participants was 48 years (SD 15) in intervention group and 46 years (SD 15) years in the control group. In the VTT group all patients were male; the indications were pneumothorax (83%), haemothorax (8%) and haemopneumothorax (8%). The median injury severity score was 23 (16-28). There were 1 positional and 1 insertional complications. In the control group 72% of patients were male, the indications were pneumothorax (56%), haemothorax (4%) and haemopneumothorax (40%). The median injury severity score was 24 (14-36). There were 8 (32%) positional complications and no insertional complications.

CONCLUSION

V-TT was demonstrated to be a feasible alternative to conventional thoracostomy and merits further investigation.

Clinical Obesity Services in Public Hospitals in Australia: a position statement based on expert consensus

We aimed to describe the current state of specialist obesity services for adults with clinically severe obesity in public hospitals in Australia, and to analyse the gap in resources based on expert consensus. We conducted two surveys to collect information about current and required specialist obesity services and resources using open-ended questionnaires. Organizational level data were sought from clinician expert representatives of specialist obesity services across Australia in 2017. Fifteen of 16 representatives of current services in New South Wales (n = 8), Queensland (n = 1), Victoria (n = 2), South Australia (n = 3), and the Australian Capital Territory (n = 1) provided data. The composition of services varied substantially between hospitals, and patient access to services and effective treatments were limited by strict entry criteria (e.g. body mass index 40 kg/m² or higher with specific complication/s), prolonged wait times, geographical location (major cities only) and out-of-pocket costs. Of these services, 47% had a multidisciplinary team (MDT), 53% had an exercise physiologist/physiotherapist, 53% had a bariatric surgeon and 33% had pharmacotherapy resources. Key gaps included staffing components of the MDT (psychologist, exercise physiologist/physiotherapist) and access to publicly funded weight loss pharmacotherapy and bariatric surgery. There was consensus on the need for significant improvements in staff, physical infrastructure, access to services, education/training in obesity medicine and targeted research funding. Based on the small number of existing, often under-resourced specialist obesity services that are located only in a few major cities, the vast majority of Australians with clinically severe obesity cannot access the specialist evidence based treatments needed.

Measurement of breath acetone in patients referred for an oral glucose tolerance test

Breath acetone concentrations were measured in 141 subjects (aged 19-91 years, mean = 59.11 years, standard deviation = 12.99 years), male and female, undergoing an oral glucose tolerance test (OGTT), having been referred to clinic on suspicion of type 2 diabetes. Breath samples were measured using an ion-molecule-reaction mass spectrometer, at the commencement of the OGTT, and after 1 and 2 h. Subjects were asked to observe the normal routine before and during the OGTT, which includes an overnight fast and ingestion of 75 g glucose at the beginning of the routine. Several groups of diagnosis were identified: type 2 diabetes mellitus positive (T2DM), n = 22; impaired glucose intolerance (IGT), n = 33; impaired fasting glucose, n = 14; and reactive hypoglycaemia, n = 5. The subjects with no diagnosis (i.e. normoglycaemia) were used as a control group, n = 67. Distributions of breath acetone are presented for the different groups. There was no evidence of a direct relationship between blood glucose (BG) and acetone measurements at any time during the study (0 h: p = 0.4482; 1 h: p = 0.6854; and 2 h: p = 0.1858). Nor were there significant differences between the measurements of breath acetone for the control group and the T2DM group (0 h: p = 0.1759; 1 h: p = 0.4521; and 2 h: p = 0.7343). However, the ratio of breath acetone at 1 h to the initial breath acetone was found to be significantly different for the T2DM group compared to both the control and IGT groups (p = 0.0189 and 0.011, respectively). The T2DM group was also found to be different in terms of ratio of breath acetone after 1 h to that at 2 h during the OGTT. And was distinctive in that it showed a significant dependence upon the level of BG at 2 h (p = 0.0146). We conclude that single measurements of the concentrations of breath acetone cannot be used as a potential screening diagnostic for T2DM diabetes in this cohort, but monitoring the evolution of breath acetone could open a non-invasive window to aid in the diagnosis of metabolic conditions.

Mental health care needs and preferences for mothers of children with a disability

BACKGROUND

Mothers of children with a disability are at increased risk of poor mental health compared with mothers of typically developing children. The aim of the study was to describe the mental health care needs and preferences for support of mothers of children and young people aged 0-25 years with a disability.

METHODS

A cross-sectional study was used, using an online survey with 294 mothers of children with a disability. Questions were asked about mental health, perceived need for support, barriers to accessing mental health care, and preferences for support. Descriptive and chi-squared analyses were performed.

RESULTS

High rates of mental ill health were self-identified in the previous 12 months, with reported clinically significant depression (44%), anxiety (42%), and suicidality (22%). Nearly half (48%) of the mothers reported high to very high psychological distress. Although 75% of mothers perceived a need for professional support, only 58% attempted to access this. Key barriers to accessing support were caregiving duties making it difficult to schedule appointments (45%) and not perceiving the mental health problem as serious enough to require help (36%). Individual counselling was the preferred type of support (66%) followed by professionally guided relaxation (49%) and education about mental health (47%). Support was considered most critical at the time of diagnosis and during medical intervention for their child.

CONCLUSIONS

Although mental health problems were common and mothers perceived the need for professional help, several key barriers were preventing mothers from accessing help. Our study suggests that improving mothers' knowledge of when and where to seek help (mental health literacy) may encourage their access to support. There also needs to be more accessible treatment to mothers given the high care demands that are placed upon them.

Factors associated with treatment delays in pediatric refractory convulsive status epilepticus

OBJECTIVE

To identify factors associated with treatment delays in pediatric patients with convulsive refractory status epilepticus (rSE).

METHODS

This prospective, observational study was performed from June 2011 to March 2017 on pediatric patients (1 month to 21 years of age) with rSE. We evaluated potential factors associated with increased treatment delays in a Cox proportional hazards model.

RESULTS

We studied 219 patients (53% males) with a median (25th-75th percentiles [p₂₅-p₇₅]) age of 3.9 (1.2-9.5) years in whom rSE started out of hospital (141 [64.4%]) or in hospital (78 [35.6%]). The median (p₂₅-p₇₅) time from seizure onset to treatment was 16 (5-45) minutes to first benzodiazepine (BZD), 63 (33-146) minutes to first non-BZD antiepileptic drug (AED), and 170 (107-539) minutes to first continuous infusion. Factors associated with more delays to administration of the first BZD were intermittent rSE (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.14-2.09; p = 0.0467) and out-of-hospital rSE onset (HR 1.5, 95% CI 1.11-2.04; p = 0.0467). Factors associated with more delays to administration of the first non-BZD AED were intermittent rSE (HR 1.78, 95% CI 1.32-2.4; p = 0.001) and out-of-hospital rSE onset (HR 2.25, 95% CI 1.67-3.02; p < 0.0001). None of the studied factors were associated with a delayed administration of continuous infusion.

CONCLUSION

Intermittent rSE and out-of-hospital rSE onset are independently associated with longer delays to administration of the first BZD and the first non-BZD AED in pediatric rSE. These factors identify potential targets for intervention to reduce time to treatment.