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Introduction: Oxygen is commonly administered to prehospital patients presenting with acute myocardial infarction (AMI). We conducted a systematic review to determine if oxygen administration, in AMI, impacts patient outcomes. Methods: We conducted a systematic search using MeSH terms and keywords in Medline, Embase, Cochrane Database of Systematic Reviews, Cochrane Central, clinicaltrials.gov and ISRCTN for relevant randomized controlled trials and observational studies comparing oxygen administration and no oxygen administration. The outcomes of interest were: mortality (≤30 days, in-hospital, and intermediate 2-11 months), infarct size, and major adverse cardiac events (MACE). Risk of Bias assessments were performed and GRADE methodology was employed to assess quality and overall confidence in the effect estimate. A meta-analysis was performed using RevMan 5 software. Results: Our search yielded 1192 citations of which 48 studies were reviewed as full texts and a total of 8 studies were included in the analysis. All evidence was considered low or very low quality. Five studies reported on mortality finding low quality evidence of no benefit or harm. Low quality evidence demonstrated no benefit or harm from supplemental oxygen administration. Similarly, no benefit or harm was found in MACE or infarct size (very low quality). Normoxia was defined as oxygen saturation measured via pulse oximetry at ≥90% in one recent study and ≥94% in another. Conclusion: We found low and very low quality evidence that the administration of supplemental oxygen to normoxic patients experiencing AMI, provides no clear harm nor benefit for mortality or MACE. The evidence on infarct size was inconsistent and warrants further prospective examination.
Introduction: Opioids are routinely administered for analgesia to prehospital patients experiencing chest discomfort from acute myocardial infarction (AMI). We conducted a systematic review to determine if opioid administration impacts patient outcomes. Methods: We conducted a systematic search using MeSH terms and keywords in Medline, Embase, Cochrane Database of Systematic Reviews, Cochrane Central and Clinicaltrials.gov for relevant randomized controlled trials and observational studies comparing opioid administration in AMI patients from 1990 to 2017. The outcomes of interest were: all-cause short-term mortality (≤30 days), major adverse cardiac events (MACE), platelet activity and aggregation, immediate adverse events, infarct size, and analgesia. Included studies were hand searched for additional citations. Risk of Bias assessments were performed and GRADE methodology was employed to assess quality and overall confidence in the effect estimate. Results: Our search yielded 3001 citations of which 19 studies were reviewed as full texts and a total of 9 studies were included in the analysis. The studies predominantly reported on morphine as the opioid. Five studies reported on mortality (≤30 days), seven on MACE, four on platelet activity and aggregation, two on immediate adverse events, two on infarct size and none on analgesic effect. We found low quality evidence suggesting no benefit or harm in terms of mortality or MACE. However, low quality evidence indicates that opioids increase infarct size. Low-quality evidence also shows reduced serum P2Y12 (eg: clopidogrel and ticagrelor) active metabolite levels and increased platelet reactivity in the first several hours post administration following an increase in vomiting. Conclusion: We find low and very low quality evidence that the administration of opioids in STEMI may be adversely related to vomiting and some surrogate outcomes including increased infarct size, reduced serum P2Y12 levels, and increased platelet activity. We found no clear benefit or harm on patient-oriented clinical outcomes including mortality.
Lowering protein level in diets for piglets urge to have knowledge on the piglet’s requirements for essential amino acids (AA) and their interactions. The present studies aimed to determine the interaction between the dietary level of valine (Val) and tryptophan (Trp) and the effect of AA imbalance at two levels of dietary Val on the growth performance of post-weaning piglets. In Experiment 1 (duration 4 weeks), the effects of supplementation of free l-Val (1.0 g/kg) and/or l-Trp (0.5 g/kg) in a low-CP diet (CP 17.7%), marginal in Trp and Val, was studied in a 2×2 factorial design and using an additional reference treatment (CP 19.5%). In Experiment 2 (duration 5 weeks), the influence of a stepwise increase in excess supply of isoleucine (Ile), histidine (His) and leucine (Leu), up to 10, 10% and 30% relative to their requirement values respectively, was evaluated at 60% or 70% standardized ileal digestible (SID) Val relative to SID lysine, using a 3×2 factorial design. In Experiment 1, over the whole experimental period, feed intake (FI) was affected by dietary Trp level (P<0.05) and feed conversion ratio (FCR) by both the level of Trp and Val in the diet (both P<0.05). Increasing Trp level increased FI and decreased FCR while increasing dietary Val level reduced FI and increased FCR. For BW gain (BWG), there was an interaction between dietary level of Trp and Val (P<0.05). Valine supplementation decreased BWG using a diet marginal in Trp, whereas it increased BWG when using a Trp sufficient diet. Piglets fed the low-CP diet with adequate levels of Val and Trp showed at least same performance compared to piglets fed the high CP reference diet. In Experiment 2, increasing dietary Val improved FI and BWG (P<0.001) and tended to improve FCR. Dietary AA excess for Ile, His and Leu reduced FI and BWG (P<0.05) and only affected FCR (P<0.01) in the 1st week of the study. Dietary level of Val and AA excess did not show interactive effects, except for FCR over the final 2 weeks of the study (P<0.05). In conclusion, an interaction exists between dietary supply of Val and Trp on the zootechnical performance of post-weaning piglets and dietary AA excess for Ile, Leu and His, reduces growth performance of piglets in low-protein diets, independent of the dietary level of Val.
We performed a spatial-temporal analysis to assess household risk factors for Ebola virus disease (Ebola) in a remote, severely-affected village. We defined a household as a family's shared living space and a case-household as a household with at least one resident who became a suspect, probable, or confirmed Ebola case from 1 August 2014 to 10 October 2014. We used Geographic Information System (GIS) software to calculate inter-household distances, performed space-time cluster analyses, and developed Generalized Estimating Equations (GEE). Village X consisted of 64 households; 42% of households became case-households over the observation period. Two significant space-time clusters occurred among households in the village; temporal effects outweighed spatial effects. GEE demonstrated that the odds of becoming a case-household increased by 4·0% for each additional person per household (P < 0·02) and 2·6% per day (P < 0·07). An increasing number of persons per household, and to a lesser extent, the passage of time after onset of the outbreak were risk factors for household Ebola acquisition, emphasizing the importance of prompt public health interventions that prioritize the most populated households. Using GIS with GEE can reveal complex spatial-temporal risk factors, which can inform prioritization of response activities in future outbreaks.
Pertussis epidemics have displayed substantial spatial heterogeneity in countries with high socioeconomic conditions and high vaccine coverage. This study aims to investigate the relationship between pertussis risk and socio-environmental factors on the spatio-temporal variation underlying pertussis infection. We obtained daily case numbers of pertussis notifications from Queensland Health, Australia by postal area, for the period January 2006 to December 2012. A Bayesian spatio-temporal model was used to quantify the relationship between monthly pertussis incidence and socio-environmental factors. The socio-environmental factors included monthly mean minimum temperature (MIT), monthly mean vapour pressure (VAP), Queensland school calendar pattern (SCP), and socioeconomic index for area (SEIFA). An increase in pertussis incidence was observed from 2006 to 2010 and a slight decrease from 2011 to 2012. Spatial analyses showed pertussis incidence across Queensland postal area to be low and more spatially homogeneous during 2006–2008; incidence was higher and more spatially heterogeneous after 2009. The results also showed that the average decrease in monthly pertussis incidence was 3·1% [95% credible interval (CrI) 1·3–4·8] for each 1 °C increase in monthly MIT, while average increase in monthly pertussis incidences were 6·2% (95% CrI 0·4–12·4) and 2% (95% CrI 1–3) for SCP periods and for each 10-unit increase in SEIFA, respectively. This study demonstrated that pertussis transmission is significantly associated with MIT, SEIFA, and SCP. Mapping derived from this work highlights the potential for future investigation and areas for focusing future control strategies.
Patients with psychosis display the so-called ‘Jumping to Conclusions’ bias (JTC) – a tendency for hasty decision-making in probabilistic reasoning tasks. So far, only a few studies have evaluated the JTC bias in ‘at-risk mental state’ (ARMS) patients, specifically in ARMS samples fulfilling ‘ultra-high risk’ (UHR) criteria, thus not allowing for comparisons between different ARMS subgroups.
In the framework of the PREVENT (secondary prevention of schizophrenia) study, a JTC task was applied to 188 patients either fulfilling UHR criteria or presenting with cognitive basic symptoms (BS). Similar data were available for 30 healthy control participants matched for age, gender, education and premorbid verbal intelligence. ARMS patients were identified by the Structured Interview for Prodromal Symptoms (SIPS) and the Schizophrenia Proneness Instrument – Adult Version (SPI-A).
The mean number of draws to decision (DTD) significantly differed between ARM -subgroups: UHR patients made significantly less draws to make a decision than ARMS patients with only cognitive BS. Furthermore, UHR patients tended to fulfil behavioural criteria for JTC more often than BS patients. In a secondary analysis, ARMS patients were much hastier in their decision-making than controls. In patients, DTD was moderately associated with positive and negative symptoms as well as disorganization and excitement.
Our data indicate an enhanced JTC bias in the UHR group compared to ARMS patients with only cognitive BS. This underscores the importance of reasoning deficits within cognitive theories of the developing psychosis. Interactions with the liability to psychotic transitions and therapeutic interventions should be unravelled in longitudinal studies.
TO apply interim surveillance definitions of Clostridium difficile infection (CDI) cases to 1 year of data from the provincewide surveillance system of Manitoba, Canada, to determine the epidemiology of CDI incident cases in a population.
CDI cases were categorized with interim surveillance definitions developed by an ad hoc C. difficile surveillance working group. Incident cases recorded in the provincial CDI database between July 2005 and June 2006 were linked to the provincial hospitalization and nursing home databases and analyzed.
One thousand six incident cases were identified over 1 year. Five hundred fifteen (51%) cases were associated with and began in a healthcare facility (HCF), whereas 275 (27%) were associated with and began in the community. An additional 131 (13%) cases were HCF associated but began in the community, while 85 (8%) were of indeterminate origin. Cases of HCF-associated CDI occurred in patients who were older than did cases of community-associated CDI (P < .0001). The provincial rate of community-onset cases was 23.4 per 100,000 person-years, and rates varied among geographic areas. HCF-associated CDI rates among the 10 largest hospitals varied from 0.5 to 8.4 per 10,000 patient-days. The time to CDI onset after hospital admission indicated that 25% of nosocomial cases began by the 8th day, and 50% began by the 17th day.
Although the majority of CDI cases were associated with exposure to a HCF, 40% of incident CDI began in the community. Populations with HCF- and community-associated CDI demonstrated significantly different age distributions. The wide variation of rates among HCFs requires explanation. The high percentage of incident cases in the community warrants increased study.
Simple alkanedithiols exhibit the same molecular conductance whether measured in air, under vacuum or under liquids of different polarity. Here, we show that the presence of water ‘gates’ the conductance of a family of oligothiophene–containing molecular wires, and that the longer the oligothiophene, the larger is the effect; for the longest example studied, the molecular conductance is over two orders of magnitude larger in the presence of water, an unprecedented result suggesting that ambient water is a crucial factor to be taken into account when measuring single molecule conductances (SMC), or in the design of future molecular electronic devices. Theoretical investigation of electron transport through the molecules, using the ab initio non-equilibrium Green's function (SMEAGOL) method, shows that water molecules interact with the thiophene rings, shifting the transport resonances enough to increase greatly the SMC of the longer, more conjugated examples.
We aimed to describe the vitamin D status of young women living in two Chinese cities in the spring – Beijing in the north (latitude 39° north) and Hong Kong (latitude 22° north) in the south. We also examined the relationship between serum 25-hydroxyvitamin D and parathyroid hormone (PTH) concentrations to determine a threshold for serum 25-hydroxyvitamin D above which there is no further suppression of PTH. Finally, we examined whether dietary Ca intake influences this relationship. Non-pregnant women aged 18–40 years (n 441) were recruited between February and June. Fasting blood was collected and dietary intakes were assessed using 5 d food records. Mean serum 25-hydroxyvitamin D concentration was lower in Beijing than Hong Kong women (29 v. 34 nmol/l; P < 0·001). Vitamin D deficiency ( ≤ 25 nmol/l) was indicated in 40 % of Beijing and 18 % of Hong Kong women, and over 90 % of women in both cities were insufficient ( ≤ 50 nmol/l). Mean Ca and vitamin D intakes were 478 mg/d and 2·0 μg/d, respectively. The relationship between 25-hydroxyvitamin D concentration and PTH was linear throughout the range with a slope of − 0·36 (different from 0; P < 0·001; R 0·26), with no apparent threshold. There was no influence of Ca intake on the relationship between 25-hydroxyvitamin D and PTH concentration. Vitamin D deficiency is common and insufficiency is very common in non-pregnant women in Hong Kong and Beijing during spring. Serum 25-hydroxyvitamin D was inversely associated with PTH with no apparent threshold. Strategies such as vitamin D fortification or supplementation may be required.
Background. Some doctors who initially choose psychiatry do not pursue it as a long-term career. The study seeks to identify reasons for leaving psychiatry.
Method. Postal questionnaire survey of UK medical graduates of 1988, 1993, 1996 and 1999 identified as having left psychiatry; for comparison, doctors who left general practice or trauma and orthopaedics.
Results. Response rate was 74% (572/778); 488 respondents satisfied study criteria (59 psychiatry, 318 general practice, 111 trauma and orthopaedics). The speciality's poor public image, perceived lack of respect from medical peers, perceived threat of violence from patients, under-resourcing and low morale were problems for psychiatry leavers. Job stress, self-assessed unsuitability, and concerns about the lack of evidence-based treatments also influenced decisions to leave psychiatry.
Conclusions. Early exposure to psychiatry may help trainees assess their suitability. Negative perceptions of workforce issues (e.g. low morale) and of clinical issues (e.g. perceived lack of ability to improve prognosis) need addressing to increase retention.
We use N-body simulations to follow the evolution of bars in the presence of a central mass concentration (CMC). We find that the bar amplitude decreases in response to the CMC, but the bar is not totally destroyed unless the CMC mass is several percent of that of the disc. More centrally concentrated CMCs are more efficient. The bar evolution does not stop after the CMC has fully grown, but continues well after that time.
The free volume changes associated with deformation of metallic glasses play an important role in strain localization in shear bands. However the details of these structural changes during inhomogeneous deformation are unclear. In this study, the free volume changes in Cu60Zr30Ti10 and Zr58.5Cu15.6Ni12.8Al10.3Nb2.8 bulk metallic glasses were examined and quantified using differential scanning calorimetry following rolling and low temperature annealing. It was found that the height of the endothermic peak associated with the glass transition decreased following deformation whereas annealing resulted in an increase in the peak height. Additionally, the exothermic event associated with structural relaxation prior to the glass transition occurred at a lower temperature after rolling in the Zr-based system. Surprisingly, a similar shift in the onset temperature was not observed in the Cu-based system, suggesting a different structural relaxation mechanism. The Zr-based system was successfully modeled and the results indicated that the free volume increased ∼4% with inhomogeneous deformation and decreased ∼14% with annealing, consistent with expectations. In an effort to further characterize strain localization in shear bands, the development of a crack tip damage zone in a Zr-based bulk metallic glass composite was studied using scanning electron and atomic force microscopy. The first shear band developed at an angle of ∼60° from the crack propagation direction. This is discussed in light of the Mohr-Coulomb yield criterion for metallic glasses. The reinforcement phase arrested the growth of individual shear bands, while accumulated damage resulted in the shear bands cutting through the crystalline phase, ultimately resulting in crack branching and failure.
An investigation was made during 1988 to test the hypothesis that ‘Grasslands Huia’ white clover
(Trifolium repens L.) could be eliminated under close sheep grazing. The effects of grazing
management, topography and fertilizer on the contribution of Huia plants to the white clover
population in an 85 ha experimental upland pasture ecosystem in the southern North Island, New
Zealand (lat. 40° 20′ S, long. 175° 50′ E, 125–350 m altitude) were quantified 11 years after
oversowing. Replicated sampling sites (108 in total) were located on nine combinations of slope and
aspect within grazing management treatments comprising rotational grazing with cattle (RC),
rotational grazing with sheep (RS) and continuous grazing with sheep (CS), with high and low
fertilizer treatments in each case. White clover occurrence, leaf area, phosphoglucoisomerase-2
(PGI-2) allele frequencies and the proportion of Grasslands Huia plants in the white clover population
were determined at each site. White clover frequency was lower on steeper slopes. Aspect, slope and
grazing management affected area of individual clover leaves. The proportion of Huia plants in the
white clover population averaged 54·9, 49·0 and 33·6% for RC, RS and CS, respectively (P < 0·039,
5 D.F.). Fertilizer and topography did not affect the proportion of Huia. It was concluded that
although Huia did persist after 11 years of close sheep grazing, its contribution to the total white
clover population was unsatisfactory in some cases, and use of better adapted cultivars is suggested.
This paper describes the use of the Neurosign 100 Nerve Monitor and vagus nerve stimulation in the identification and assessment of the integrity of the recurrent laryngeal nerve (RLN) during thyroid and parathyroid surgery.
Vocal fold function was assessed pre- and post-operatively in all patients undergoing thyroid and parathyroid surgery. The nerve monitor, used in association with endotracheal electrodes, was used to confirm correct RLN identification and demonstrate its integrity at the completion of surgery.
There were 21 unilateral and 19 bilateral neck explorations. In these 40 patients, 57 of 59 RLNs were identified. The nerve monitor demonstrated RLN continuity in all but one case (equipment failure: electrode misplacement) after initial identification. Vagus nerve stimulation was performed in 21 patients without adverse sequelae. Damage to the RLN was identified in one of these patients, in whom direct RLN stimulation close to the larynx had failed to indicate discontinuity. Post-operatively this patient had a transient unilateral vocal fold palsy.
The use of the Neurosign 100 Nerve Monitor is no substitute for meticulous surgery. Stimulation of the vagus nerve may be a more sensitive means of assessing RLN integrity during thyroid and parathyroid surgery than stimulation of the RLN itself. Confirmation of RLN integrity allows the surgeon to proceed with confidence to the contralateral side of the neck during hazardous bilateral explorations.
Decades ago, prominent theorists assumed that loneliness could only be experienced in adolescence and adulthood when needs for social intimacy, beyond those which parents could provide, were thought to begin (e.g., Sullivan, 1953; Weiss, 1973). This reasoning is reminiscent of psychoanalytic theorists who likewise believed that children could not experience depression (see Rutter, 1986). Similar to theory and research on depression, such thinking may have stultified empirical work on loneliness in young children because very few studies have been conducted on loneliness at this stage of development. Recently, however, researchers have recognized that, along with the need to be physically and emotionally close to significant others, young children are able to discern their social situation and emotional state. An initial estimate that about 10% of 5- to 7-year-old children feel very lonely or dissatisfied with their social relationships at school (Cassidy & Asher, 1992) supports the notion that young children can actually feel sadness about solitude. Furthermore, children in kindergarten and first grade comprehend the concept of loneliness, reporting that loneliness is “a feeling of being sad and alone” (Cassidy & Asher, 1992).
Given the incidence of loneliness in early childhood and the importance of this phenomenon, the researchers in our lab have studied loneliness among young children in the school environment. Our starting point for investigation was the fall of kindergarten, a time when children have just entered grade school and are making a transition to a new setting and social situation. Hymel, Tarulli, Hayden Thomson, and Terrell-Deutsch (this volume) have reported that feeling lonely often accompanies the occurrence of major life events, such as loss of a significant other or moving to an unfamiliar place.