Perceptions of friendship, peers and influence on adolescent smoking according to tobacco control context: a systematic review and meta-ethnography of qualitative research.

BACKGROUND: A relationship between smoking and interpersonal influences has been well established within the literature. There have been cultural shifts in denormalisation and a reduction in tobacco smoking in many countries. Hence there is a need to understand social influences on adolescents' smoking across smoking normalisation contexts. METHODS: The search was conducted in July 2019 and updated in March 2022 within 11 databases and secondary sources. Search terms included schools, adolescents, smoking, peers, social norms and qualitative research. Screening was conducted by two researchers independently and in duplicate. Study quality was assessed using the eight-item Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-centre) tool for the appraisal of qualitative studies. Results were synthesised using a meta-narrative lens for meta-ethnography and compared across smoking normalisation contexts. RESULTS: Forty one studies were included and five themes were developed, mapping onto the socio ecological model. The social processes by which adolescents take up smoking differed according to a mixture of school type, peer group structure and the smoking culture within the school, as well as the wider cultural context. Data available from smoking denormalised contexts, described changes in social interactions around smoking to cope with its stigmatisation. This was manifested through i) direct peer influence, whereby subtle techniques were employed, ii) group belonging whereby smoking was less likely to be seen as a key determinant of group membership and smoking was less commonly reported to be used as a social tool, and iii) popularity and identity construction, whereby smoking was perceived more negatively in a denormalised context, compared with a normalised context. CONCLUSIONS: This meta-ethnography is the first study to demonstrate, drawing on international data, that peer processes in adolescent smoking may undergo changes as smoking norms within society change. Future research should focus on understanding differences across socioeconomic contexts, to inform the adaptation of interventions.

Exploring the association between school-based peer networks and smoking according to socioeconomic status and tobacco control context: a systematic review.

BACKGROUND: Whilst prevalence of youth smoking in middle and high income countries has decreased, inequality has prevailed. The introduction of legislation regulating tobacco use in public spaces varies across countries, impacting the tobacco control context. Thus reviewing our knowledge of how social networks may influence smoking differently within different contexts is required to facilitate the development of context-specific interventions. METHODS: The search, conducted on 31st May 2019, included the following smoking-related terms; schools, adolescents, peers and social networks. Inclusion and exclusion criteria were applied throughout the title and abstract screening and full text screening. Quality assessment and synthesis followed. Studies were narratively synthesised to identify changes according to legislative context. This synthesis was conducted separately for findings relating to three categories: socioeconomic status; social selection and influence; and network position. RESULTS: Thirty studies were included. Differences in the relationship between network characteristics and smoking according to socioeconomic status were measured in five out of fifteen studies in Europe. Results varied across studies, with differences in network characteristics and their association with smoking varying both between schools of a differing and those of a similar socioeconomic composition. For studies conducted both before and after the introduction of comprehensive smoking legislation, the evidence for selection processes was more consistent than influence, which varied according to reciprocity. Findings showed that isolates were more likely to smoke and in-degree and out-degree centrality were related to smoking both before and after the introduction of legislation. The relationship between popularity and smoking was contingent on school level smoking prevalence in studies conducted before the introduction of legislation, but not after. CONCLUSIONS: Overall, effects according to socioeconomic status were underreported in the included studies and no consistent evidence of change after the introduction of a comprehensive smoking ban was observed. Further network analyses are required using more recent data to obtain a comprehensive understanding of how network processes may influence smoking differently according to socioeconomic status, and how adaptation could be used to enhance intervention effectiveness. SYSTEMATIC REVIEW REGISTRATION: International Prospective Register of Systematic Reviews (PROSPERO) registration number: CRD42019137358 .

Factors influencing hospital conveyance following ambulance attendance for people with diabetes: A retrospective observational study.

AIM: To assess variables contributing to hospital conveyance for people with diabetes and the interactions between them. A secondary aim was to generate hypotheses for further research into interventions that might reduce avoidable hospital admissions. METHODS: A national retrospective data set including 30 999 diabetes-related callouts from the Scottish Ambulance Service was utilized covering a 5-year period between 2013 and 2017. The relationship between diabetes-related hospital conveyance and seven potential risk factors was analysed. Independent variables included: age, gender, deprivation, paramedic attendance, treatment at the scene, first blood glucose measurement and day of the week. RESULTS: In Scotland, hyperglycaemia was associated with a higher number of people being conveyed to hospital than hypoglycaemia (49.8% with high blood glucose vs. 39.3% with low glucose, P ≤ 0.0001). Treatment provided in pre-hospital care was associated with reduced conveyance rates (47.3% vs. 58.2% where treatment was not administered, P ≤ 0.0001). Paramedic attendance was also associated with reduced conveyance to hospital (51.4% vs. 59.5% where paramedic was not present, P ≤ 0.0001). Paramedic attendance in hyperglycaemic cases was associated with significantly reduced odds of conveyance (odds ratio 0.52, P ≤ 0.001). CONCLUSIONS: A higher rate of conveyance associated with hyperglycaemic cases indicates a need for more resources, education and training in this area. Higher conveyance rates were also associated with no paramedic being present and no treatment being administered. This suggests that paramedic attendance may be crucial in reducing avoidable admissions. Developing and validating protocols for pre-hospital services and treatment may help to reduce hospital conveyance rates.

Antibacterial activity and carbapenem re-sensitizing ability of 1,10-phenanthroline-5,6-dione and its metal complexes against KPC-producing Klebsiella pneumoniae clinical strains.

Infections caused by KPC-producing Klebsiella pneumoniae (Kp-KPC) are associated with high mortality rates due to the increased number of resistant isolates and the scarcity of therapeutic options. This scenario reinforces the urgent need for new chemotherapeutics. Herein, we investigated the effects of 1,10-phenanthroline-5,6-dione (phendione) and its metal-based complexes, [Cu(phendione)3 ](ClO4 )2 .4H2 O (Cu-phendione) and [Ag(phendione)2 ]ClO4 (Ag-phendione), both alone and also combined with carbapenems (meropenem (MEM), and imipenem), against 46 clonally distinct clinical strains of Kp-KPC. All isolates were found to be multidrug resistant in accordance with their susceptibility patterns by disk diffusion method. Compounds geometric mean (GM)-MIC and GM-MBC values (µmol l-1 ), respectively, were: phendione, 42·06 and 71·27; Cu-phendione, 9·88 and 13·75; and Ag-phendione, 10·10 and 13·06. Higher synergism rates of MEM-containing combinations were observed by the checkerboard assay, particularly with the two metal complexes. Moreover, drug combinations were able to re-sensitize 87% of the phenotypically non-susceptible strains. Time-kill studies, with MEM plus Cu-phendione or Ag-phendione, indicated that combinations with 0·5× MIC of each agent produce synergistic effects after 9-12 h. The MEM plus Ag-phendione eradicated about 106  CFU per ml of bacteria. These findings support the effectiveness of the re-sensitizing combinatorial approach and provide evidence that phendione-based compounds offer real promise in the fight against Kp-KPC infections.

A patient and public involvement investigation into healthy eating and weight management advice during pregnancy.

OBJECTIVE: To conduct patient and public involvement (PPI) to gain insight into the experience of healthy eating and weight management advice during pregnancy. DESIGN: PPI in the planning and development of health interventions, aiming to ensure patient-centred care. Optimum nutrition and weight management are vital for successful pregnancy outcomes, yet many services report poor attendance and engagement. SETTING: Community venues in Liverpool and Ulster (UK). PARTICIPANTS: Two PPI representatives were involved in all aspects of the study: design, interview questions, recruitment and collection/analysis of feedback. INTERVENTION: Feedback was collected via note taking during group discussions, two in Liverpool (n = 10 & 5); two in Ulster (n = 7 & 9) and an interview (n = 1, in Ulster). MAIN OUTCOME MEASURES: Transcript data were collated and thematic analysis was applied in analysis. RESULTS: Thematic analysis identified three themes: (i) weight gain is inevitable in pregnancy; (ii) healthy eating advice is important but currently lacks consistency and depth and (iii) expectations regarding the type of knowledge/support. CONCLUSIONS: PPI provides opportunity to enhance research design and offers valuable insight towards the needs of healthcare users. Pregnant women want positive health messages, with a focus on what they can/should do, rather than what they should not do. Midwives need to consider their communication with pregnant women, to ensure that their unique relationship is maintained, especially when the topics of diet and weight management are addressed. A well-designed digital intervention could improve access to pregnancy-specific nutrition information; empowering midwives to communicate patient-centred, healthy eating messages with confidence. This has the potential to change dietary and weight management behaviour in pregnant women.

C57BL/6 mice are resistant to joint degeneration induced by whole-body vibration.

OBJECTIVE: Whole-body vibration (WBV) platforms are commercially available devices that are used clinically to treat numerous musculoskeletal conditions based on their reported ability to increase bone mineral density and muscle strength. Despite widespread use, there is an alarming lack of understanding of the direct effects of WBV on joint health. Previous work by our lab demonstrated that repeated exposure to WBV using protocols that model those used clinically, induces intervertebral disc (IVD) degeneration and osteoarthritis-like damage in the knee of skeletally mature, male mice of a single outbred strain (CD-1). The present study examined whether exposure to WBV induces similar deleterious effects in a genetically different strain of mouse (C57BL/6). DESIGN: Male 10-week-old C57BL/6 mice were exposed to vertical sinusoidal WBV for 30 min/day, 5 days/week, for 4 or 8 weeks using previously reported protocols (45 Hz, 0.3 g peak acceleration). Following WBV, joint tissues were examined using histological analysis and gene expression was quantified using real-time PCR (qPCR). RESULTS: Our analyses show a lack of WBV-induced degeneration in either the knee or IVDs of C57BL/6 mice exposed to WBV for 4 or 8 weeks, in direct contrast to the WBV-induced damage previously reported by our lab in CD-1 mice. CONCLUSIONS: Together with previous studies from our group, the present study demonstrates that the effects of WBV on joint tissues vary in a strain-specific manner. These findings highlight the need to examine genetic or physiological differences that may underlie susceptibility to the deleterious effects of WBV on joint tissues.

Whole-body vibration of mice induces articular cartilage degeneration with minimal changes in subchondral bone.

OBJECTIVE: Low-amplitude, high-frequency whole-body vibration (WBV) has been adopted for the treatment of musculoskeletal diseases including osteoarthritis (OA); however, there is limited knowledge of the direct effects of vibration on joint tissues. Our recent studies revealed striking damage to the knee joint following exposure of mice to WBV. The current study examined the effects of WBV on specific compartments of the murine tibiofemoral joint over 8 weeks, including microarchitecture of the tibia, to understand the mechanisms associated with WBV-induced joint damage. DESIGN: Ten-week-old male CD-1 mice were exposed to WBV (45 Hz, 0.3 g peak acceleration; 30 min/day, 5 days/week) for 4 weeks, 8 weeks, or 4 weeks WBV followed by 4 weeks recovery. The knee joint was evaluated histologically for tissue damage. Architecture of the subchondral bone plate, subchondral trabecular bone, primary and secondary spongiosa of the tibia was assessed using micro-CT. RESULTS: Meniscal tears and focal articular cartilage damage were induced by WBV; the extent of damage increased between 4 and 8-week exposures to WBV. WBV did not alter the subchondral bone plate, or trabecular bone of the tibial spongiosa; however, a transient increase was detected in the subchondral trabecular bone volume and density. CONCLUSIONS: The lack of WBV-induced changes in the underlying subchondral bone suggests that damage to the articular cartilage may be secondary to the meniscal injury we detected. Our findings underscore the need for further studies to assess the safety of WBV in the human population to avoid long-term joint damage.

Differences in Blood Pressure in Infants After General Anesthesia Compared to Awake Regional Anesthesia (GAS Study-A Prospective Randomized Trial).

BACKGROUND: The General Anesthesia compared to Spinal anesthesia (GAS) study is a prospective randomized, controlled, multisite, trial designed to assess the influence of general anesthesia (GA) on neurodevelopment at 5 years of age. A secondary aim obtained from the blood pressure data of the GAS trial is to compare rates of intraoperative hypotension after anesthesia and to identify risk factors for intraoperative hypotension. METHODS: A total of 722 infants ≤60 weeks postmenstrual age undergoing inguinal herniorrhaphy were randomized to either bupivacaine regional anesthesia (RA) or sevoflurane GA. Exclusion criteria included risk factors for adverse neurodevelopmental outcome and infants born at <26 weeks of gestation. Moderate hypotension was defined as mean arterial pressure measurement of <35 mm Hg. Any hypotension was defined as mean arterial pressure of <45 mm Hg. Epochs were defined as 5-minute measurement periods. The primary outcome was any measured hypotension <35 mm Hg from start of anesthesia to leaving the operating room. This analysis is reported primarily as intention to treat (ITT) and secondarily as per protocol. RESULTS: The relative risk of GA compared with RA predicting any measured hypotension of <35 mm Hg from the start of anesthesia to leaving the operating room was 2.8 (confidence interval [CI], 2.0-4.1; P < .001) by ITT analysis and 4.5 (CI, 2.7-7.4, P < .001) as per protocol analysis. In the GA group, 87% and 49%, and in the RA group, 41% and 16%, exhibited any or moderate hypotension by ITT, respectively. In multivariable modeling, group assignment (GA versus RA), weight at the time of surgery, and minimal intraoperative temperature were risk factors for hypotension. Interventions for hypotension occurred more commonly in the GA group compared with the RA group (relative risk, 2.8, 95% CI, 1.7-4.4 by ITT). CONCLUSIONS: RA reduces the incidence of hypotension and the chance of intervention to treat it compared with sevoflurane anesthesia in young infants undergoing inguinal hernia repair.

Effect of dietary phosphorus on intestinal phosphorus absorption in growing Holstein steers.

The effect of dietary P intake on intestinal P absorption was evaluated in growing Holstein steers. Diets varying in P content (0.15, 0.27, 0.36, and 0.45%, DM basis) were fed to 8 steers (174±10kg of BW) fitted with permanent duodenal and ileal cannulas in a replicated 4×4 Latin square with 14-d periods. Ytterbium-labeled corn silage and cobalt-EDTA were used as particulate and liquid phase markers, respectively, to measure digesta flow. Duodenal and ileal samples and spot urine samples were collected every 9 h from d 11 to 14. Total fecal collection was conducted on d 11 to 14 with fecal bags. Blood samples were collected from the coccygeal vessel on d 14. Feed, digesta, and fecal samples were analyzed for total P and inorganic P. Data were analyzed using PROC GLIMMIX in SAS with a model including treatment, square, period, and interaction of treatment and square. Preplanned contrasts were used to evaluate linear and quadratic treatment effects. Results were reported as least squares means. Dry matter intake (mean=4.90kg/d, 2.8% of BW) and apparent DM digestibility (mean=78.1%) were unaffected by treatment. Duodenal and ileal flow of total P increased linearly with increasing P intake (13.4, 18.5, 23.0, and 27.4g/d; 6.80, 7.87, 8.42, and 10.4g/d). Increasing P intake increased the quantity of P absorbed from the small intestine linearly (6.96, 11.1, 14.6, and 17.2g/d), but absorption efficiency was unchanged (mean=59.6%). Phosphorus was absorbed on a net basis from the large intestine, but this was not affected by treatment and was a small proportion of total P absorption. Blood inorganic P increased linearly with increased dietary P (4.36, 6.31, 7.68, and 8.5mg/dL) and salivary P secretion was unchanged (mean=5.79g/d), suggesting that rumen function was prioritized during short-term P deficiency. These data showing an absence of change in absorption efficiency and salivary P secretion in the face of short-term P deficiency may be used to improve published models of P digestion, absorption, and metabolism.

Pulmonary artery blood flow patterns in fetuses with pulmonary outflow tract obstruction.

OBJECTIVES: Fetuses with pulmonary outflow tract obstruction (POTO) have altered blood flow to the pulmonary vasculature. We sought to determine whether pulmonary vascular impedance, as assessed by the pulsatility index (PI), is different in fetuses with POTO compared with normal controls. METHODS: Branch pulmonary artery PI was evaluated in age-matched normal control fetuses (n=22) and 20 POTO fetuses (pulmonary stenosis n=15, pulmonary atresia n=5). Pulsed-wave Doppler was performed in the proximal (PA1), mid (PA2) and distal (PA3) branch pulmonary artery. The direction of flow in the ductus arteriosus was noted. The study and control groups were compared with Student's t-test and ANOVA. A linear mixed model evaluated the relationship between PI and ductus arteriosus flow patterns. RESULTS: There was no difference in PI between control, pulmonary stenosis and pulmonary atresia subjects at PA1 and PA2; however, there was a significant difference at PA3. Subjects with pulmonary atresia had a lower PI at PA3 than did controls (P=0.003) and pulmonary stenosis subjects (P=0.003). Subjects with retrograde flow in the ductus arteriosus had lower PIs in PA2 and PA3 than did those with antegrade flow (P=0.01 and 0.005, respectively). The PI in PA3 was lower in fetuses that required prostaglandin postnatally than in those that did not (P=0.008). CONCLUSIONS: Fetuses with pulmonary atresia or severe pulmonary stenosis with retrograde flow in the ductus arteriosus have decreased PI in the distal pulmonary vasculature. Our findings indicate the capacity of the fetal pulmonary vasculature to vasodilate in response to anatomical obstruction of flow.

Transfer of verocytotoxigenic Escherichia coli O157, O26, O111, O103 and O145 from fleece to carcass during sheep slaughter in an Irish export abattoir.

The purpose of this study was to investigate carriage and transfer of verocytotoxigenic Escherichia coli (VTEC) O157, O26, O111, O103 and O145 from fleece to dressed carcasses of 500 sheep, and to establish the virulence potential of recovered VTEC. Individual sheep were tracked and sampled (10 g fleece, full carcass swab) through the slaughter process. Samples were examined for the presence of verotoxin (vt1 and vt2) genes using a duplex real-time PCR assay and positive samples were further screened for the presence of the above five serogroups by real-time PCR. VTEC cells were recovered from PCR positive samples by serogroup specific immunomagnetic separation and confirmed by serogroup specific latex agglutination and PCR. Isolates were subject to a virulence screen (vt1, vt2, eaeA and hlyA) by PCR and isolates carrying vt genes were examined by Pulsed-Field Gel Electrophoresis (PFGE). VTEC O26 was recovered from 5/500 (1.0%) fleece and 2/500 (0.4%) carcass samples. VTEC O157 was isolated from 4/500 (0.8%) fleece samples and 3/500 (0.6%) carcass samples. E. coli O103 was recovered from 84/500 (16.8%) fleece and 68/500 (13.6%) carcasses, but only one E. coli O103 isolate (0.2%) carried vt genes. E. coli O145 was recovered from one fleece sample, but did not carry vt genes. E. coli O111 was not detected in any samples. For the four serogroups recovered, the direct transfer from fleece to carcass was not observed with PFGE showing that VTEC O26 isolates from a matched fleece/carcass "pair" were not identical. This study shows that while VTEC O157 are being carried by sheep presented for slaughter in Ireland, other potentially clinically significant verotoxin producing strains (particularly VTEC O26) are emerging.

Comparative analysis of cerebrovascular resistance in fetuses with single-ventricle congenital heart disease.

OBJECTIVE: We sought to determine whether the presence or absence of aortic obstruction impacts cerebrovascular resistance in fetuses with single-ventricle (SV) congenital heart disease (CHD). METHODS: Pulsatility indices (PIs) were recorded for the middle cerebral artery (MCA) and the umbilical artery (UA) from 18 to 40 weeks' gestation in 59 fetuses (163 examinations) with SV-CHD with unobstructed aortic flow, yet decreased pulmonary flow, in 72 fetuses (170 examinations) with obstructed aortic flow and hypoplastic left heart syndrome (HLHS) and in 92 normal fetuses (92 examinations). The cerebral-to-placental resistance (CPR) was calculated as the MCA-PI/UA-PI. Z-scores were generated for the MCA-PI and the UA-PI in order to make comparisons independent of gestational age. Statistical analyses were performed using one-way ANOVA with post-hoc testing. Trends in these variables over the course of gestation were assessed using linear regression and univariate ANOVA. RESULTS: The MCA-PI and the CPR were significantly lower in SV fetuses with aortic obstruction compared with SV fetuses with pulmonary obstruction and with normal fetuses. Moreover, the MCA-PI decreased significantly for SV fetuses with aortic obstruction over the course of gestation. In contrast, the MCA-PI was higher over the course of gestation in SV fetuses with pulmonary obstruction compared with normal fetuses. CONCLUSION: In fetuses with SV-CHD, cerebrovascular resistance varies substantially between fetuses with and without aortic obstruction. Compared with normal fetuses, cerebrovascular resistance is decreased in SV fetuses with aortic obstruction, yet increased in SV fetuses with pulmonary obstruction. In fetuses with SV physiology, inherent differences in cerebral blood flow may underlie postnatal neurodevelopmental outcomes.

Perioperative central nervous system injury in neonates.

Anaesthetic-induced developmental neurotoxicity (AIDN) has been clearly established in laboratory animal models. The possibility of neurotoxicity during uneventful anaesthetic procedures in human neonates or infants has led to serious questions about the safety of paediatric anaesthesia. However, the applicability of animal data to clinical anaesthesia practice remains uncertain. The spectre of cerebral injury due to cerebral hypoperfusion, metabolic derangements, coexisting disease, and surgery itself further muddles the picture. Given the potential magnitude of the public health importance of this issue, the clinician should be cognisant of the literature and ongoing investigations on AIDN, and raise awareness of the risks of both surgery and anaesthesia.

Growth and risk factors for expansion of dilated popliteal arteries.

OBJECTIVES: The aims of this study were to investigate the change in maximum diameter of ectatic popliteal arteries during ultrasound surveillance and assess clinical predictors of their expansion. METHODS: Over a ten year period 67 patients with ectasia affecting one (n = 1) or both (n = 66) popliteal arteries entered this surveillance study. Patients were followed for a median of 3.1 years, at a median scan interval of 7.6 months. RESULTS: Growth of ectatic popliteal arteries was typically slow (<1 mm/yr). Initial artery diameter at entry to the study was not found to be predictive of subsequent growth. Seven patients followed for a median of 2 years had an expansion in popliteal artery diameter to >or=20 mm during follow-up. All of these patients had undergone aneurysm repairs at other arterial sites and none of them had diabetes. These participants also had a significantly higher rate of previous intervention of the contralateral popliteal artery in comparison to those that did not reach the 20 mm threshold (p < 0.001). Growth profiles of arteries that underwent significant expansion during surveillance were frequently characterised by a staccato pattern. CONCLUSIONS: Expansion of ectatic popliteal arteries is typically slow but difficult to predict. Trends observed in this study suggest that patients with extra-popliteal aneurysms, patients with previously treated contralateral popliteal artery ectasia and those who are not diabetics may be more prone to significant expansion. Further studies are required to validate these potential growth predictors.

Fetal cardiovascular effects of lower urinary tract obstruction with giant bladder.

OBJECTIVE: Lower urinary tract obstruction (LUTO) with massive bladder distension impacts on a variety of developing organ systems with consequent morbidity and mortality. The impact of LUTO on the fetal cardiovascular system has not previously been investigated. We hypothesize that a giant, distended bladder within the pelvis may cause vascular compression with observable consequences. METHODS: Fetal echocardiography was performed in 42 fetuses with LUTO and compared with 35 normal controls matched for gestational age. Parameters investigated included cardiothoracic ratio, presence or absence of ventricular hypertrophy and pericardial effusion. Doppler echocardiographic examination of mitral and tricuspid valve inflow and the ductus venosus was performed. To assess arterial vascular impedance, pulsatility indices (PIs) were calculated for segments of the descending aorta and right and left iliac arteries (RIA and LIA). RESULTS: In the LUTO group an increased cardiothoracic ratio was seen in nine (21%), ventricular hypertrophy in 12 (29%) and small pericardial effusion in 15 (36%). Filling characteristics of the right ventricle in the LUTO group demonstrated greater dependency upon atrial contraction, and ductus venosus flow demonstrated higher downstream impedance to filling, than in controls, suggesting altered compliance. The LUTO group also had lower distal descending aorta PI (1.53 ± 0.38 vs. 1.76 ± 0.44, P = 0.04), lower RIA-PI (1.31 ± 0.29 vs. 1.76 ± 0.44, P < 0.001) and lower LIA-PI (1.41 ± 0.44 vs. 1.73 ± 0.31, P < 0.01) than controls, suggesting vascular compression and increased impedance to flow. CONCLUSIONS: LUTO with giant urinary bladder compresses the iliac arteries, which may lead to increased afterload. Further study is warranted to examine the impact of fetal treatment such as bladder drainage on these cardiovascular parameters.

Oxytocin secretion in response to cholecystokinin and food: differentiation of nausea from satiety.

Administration of cholecystokinin (CCK) to rats caused a dose-dependent increase in plasma levels of the neurohypophyseal hormone oxytocin (OT). The OT secretion was comparable to that found in response to nausea-producing chemical agents that cause learned taste aversions. The effect of CCK on OT secretion was blunted after gastric vagotomy, as was the inhibition of food intake induced by CCK. Food ingestion also led to elevated plasma OT in rats, but CCK and aversive agents caused even greater OT stimulation. Thus, after administration of large doses of CCK, vagally mediated activation of central nausea pathways seems to be predominantly responsible for the subsequent decrease in food intake. Despite their dissimilar affective states, both nausea and satiety may activate a common hypothalamic oxytocinergic pathway that controls the inhibition of ingestion.

High incidence of profound biotinidase deficiency detected in newborn screening blood spots in the Somalian population in Minnesota.

Newborns identified with profound biotinidase deficiency (BTD) by the Minnesota Newborn Screening Program (MN NBS) between 1 October 2004 and 30 May 2008 were all from new immigrant groups. Thirty-three positive cases of BTD were identified out of 264 727 infants screened by the Wolf colorimetric system during the period of this study by MN NBS. Five cases of profound BTD (0.1 to <0.6 nmol/min per ml) and 26 cases of partial BTD (0.9 to 2.3 nmol/min per ml) were later confirmed through measurement of serum biotinidase activity. The incidence of combined partial and profound BTD of 1/8540 and that of profound BTD of 1/52 945 in Minnesota are unusually high in comparison with the reported worldwide numbers of 1/61 067 for combined BTD and 1/137 401 for profound BTD. Four out of the 5 cases of profound BTD ascertained in the MN NBS cohort were of Somali ethnic background, and the remaining case was of Asian (Pakistani/Indian) ethnic background. All four Somali patients have the P497S mutation, with one of the four being homozygous for the mutation. The three compound heterozygotes all have a novel mutation (P142T) and two of them have another change (Y428Y) that has never been described. Within the last two decades, Minnesota has become home to an estimated 40 000 Somali immigrants and their children (<1% of the total Minnesota population). New population demographics prompt careful analysis of case cohorts to identify specific groups at risk for rare inborn errors of metabolism.

Effects of reduction in beef surface water activity on the survival of Salmonella Typhimurium DT104 during heating.

AIM: To investigate the influence of reducing beef surface water activity (a(w)) on the survival of Salmonella Typhimurium DT104 during heating. METHODS AND RESULTS: Beef discs were surface inoculated with S. Typhimurium DT104 and either untreated or dried to achieve surface a(w) values of 0.95, 0.85 and 0.70. The samples were vacuum packed, heat-treated at 60 degrees C and removed at predetermined times. The inactivation curves were influenced by a(w) and treatment time. Biphasic inactivation curves were observed for S. Typhimurium DT104 heat-treated on beef samples with altered a(w) values, which were characterized by an initial decline in cell numbers at commencement of heating followed by a much slower rate of inactivation during the remaining treatment period. Point estimates of the heating time required to achieve a 1 log reduction on beef surfaces with a(w) of 0.99, 0.95, 0.85 and 0.70 were 0.5, 1.55, 11.25 and 17.79 min, respectively. CONCLUSIONS: A decrease in beef surface a(w) can substantially enhance the survival of S. Typhimurium DT104 after heating. SIGNIFICANCE AND IMPACT OF THE STUDY: Caution needs to be taken using dry air as a decontamination method as this may rapidly decrease product surface and pathogen a(w) values resulting in enhanced survival.

The survival of Salmonella enterica serovar Typhimurium DT104 and total viable counts on beef surfaces at different relative humidities and temperatures.

AIMS: The aim of this study was to investigate changes in Salmonella and total viable count (TVC) survival on beef carcass surfaces stored for 72 h under different combinations of relative humidity (i.e. RH 75% or 96%) and temperature (5 degrees C or 10 degrees C). METHODS AND RESULTS: The influence of low water activity (a(w)) and temperature on the survival and growth of Salmonella enterica serovar Typhimurium DT104 and the aerobic mesophilic flora on meat pieces from different sites on beef carcasses was investigated, under controlled conditions (75% or 96% RH; 5 or 10 degrees C) in an environmental cabinet. Salmonella counts declined during storage at low a(w) (75% RH) conditions at 5 degrees C or 10 degrees C. Salmonella counts increased during storage at high a(w) (96% RH) at 10 degrees C only. At 5 degrees C, TVCs increased during storage at high a(w), but not at low a(w). TVCs increased on all samples from carcasses stored at high or low a(w) at 10 degrees C, except those samples taken from areas of surface fat. CONCLUSIONS: This suggests that substrate composition dictates growth rates under low a(w) conditions. The results are discussed in terms of the possible protective effects of substrate osmolyte accumulation in bacterial survival and/or growth. SIGNIFICANCE AND IMPACT OF THE STUDY: The data obtained in this study provides useful insights on the influence of a(w) and temperature on pathogen survival on meat surfaces at chill temperature.