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Background

To investigate the effectiveness of combining teamwork training and lean process improvement, two distinct approaches to improving surgical safety. We conducted a controlled interrupted time series study in a specialist UK Orthopaedic hospital incorporating a plastic surgery team (which received the intervention) and an Orthopaedic theatre team acting as a control.

Study Design

We used a 3 month intervention with 3 months data collection period before and after it. A combined teamwork training and lean process improvement intervention was delivered by an experienced specialist team. Before and after the intervention we evaluated team non-technical skills using NOTECHS II, technical performance using the glitch rate and WHO checklist compliance using a simple 3 point scale. We recorded complication rate, readmission rate and length of hospital stay data for 6 months before and after the intervention.

Results

In the active group, but not the control group, full compliance with WHO Time Out (T/O) increased from 14 to 71% (p = 0.032), Sign Out attempt rate (S/O) increased from 0% to 50% (p<0.001) and Oxford NOTECHS II scores increased after the intervention (P = 0.058). Glitch rate decreased in the active group and increased in the control group (p = 0.001). Complications and length of stay appeared to rise in the control group and fall in the active group.

Conclusions

Combining teamwork training and systems improvement enhanced both technical and non-technical operating team process measures, and were associated with a trend to better safety outcome measures in a controlled study comparison. We suggest that approaches which address both system and culture dimensions of safety may prove valuable in reducing risks to patients.  相似文献   
126.
Glucagon‐like peptide (GLP‐1) increases insulin secretion but is rapidly degraded (half‐life: 2 min in circulation). GLP‐1 analogue, exenatide (Byetta) has a longer half‐life (3.3–4 h) with potent insulinotropic effects but requires cold storage, daily abdominal injections with short shelf life. Because patients with diabetes take >60 000 injections in their life time, alternative delivery methods are highly desired. Exenatide is ideal for oral delivery because insulinotropism is glucose dependent, with reduced risk of hypoglycaemia even at higher doses. Therefore, exendin‐4 (EX4) was expressed as a cholera toxin B subunit (CTB)–fusion protein in tobacco chloroplasts to facilitate bioencapsulation within plant cells and transmucosal delivery in the gut via GM1 receptors present in the intestinal epithelium. The transgene integration was confirmed by PCR and Southern blot analysis. Expression level of CTB‐EX4 reached up to 14.3% of total leaf protein (TLP). Lyophilization of leaf material increased therapeutic protein concentration by 12‐ to 24‐fold, extended their shelf life up to 15 months when stored at room temperature and eliminated microbes present in fresh leaves. The pentameric structure, disulphide bonds and functionality of CTB‐EX4 were well preserved in lyophilized materials. Chloroplast‐derived CTB‐EX4 showed increased insulin secretion similar to the commercial EX4 in beta‐TC6, a mouse pancreatic cell line. Even when 5000‐fold excess dose of CTB‐EX4 was orally delivered, it stimulated insulin secretion similar to the intraperitoneal injection of commercial EX4 but did not cause hypoglycaemia in mice. Oral delivery of the bioencapsulated EX4 should eliminate injections, increase patient compliance/convenience and significantly lower their cost.  相似文献   
127.
3-Nitropropionic acid (3-NP), a potent irreversible inhibitor of mitochondrial complex II enzyme, leads to mitochondrial dysfunction and oxidative stress in Huntington's disease (HD) rat model. In this study, biochemical assays were used to demonstrate the presence of oxidative stress and mitochondrial dysfunction in 3-NP early stage HD rat models. Gas chromatography time-of-flight mass spectrometry (GC/TOFMS) was applied to analyze metabolites in brain and plasma of 3-NP-treated and vehicle-dosed rats. The orthogonal partial least-squares discriminant analysis (OPLS-DA) model generated using brain metabolic profiles robustly differentiated the 3-NP early stage HD rat model from the control. Metabonomic characterization of the 3-NP HD rat model facilitated the detection of biomarkers that define the physiopathological phenotype of early stage HD and elucidated the treatment effect of galantamine. Brain marker metabolites that were identified based on the OPLS-DA model were associated with altered glutathione metabolism, oxidative stress, and impaired energy metabolism. The treatment effect of galantamine in early stage HD could not be concluded mechanistically using the brain metabotype. Our study confirmed that GC/TOFMS is a strategic and complementary platform for the metabonomic characterization of 3-NP induced neurotoxicity in the early stage HD rat model.  相似文献   
128.
We report the first study of the bacterial microbiome of ovine interdigital skin based on 16S rRNA by pyrosequencing and conventional cloning with Sanger-sequencing. Three flocks were selected, one a flock with no signs of footrot or interdigital dermatitis, a second flock with interdigital dermatitis alone and a third flock with both interdigital dermatitis and footrot. The sheep were classified as having either healthy interdigital skin (H) and interdigital dermatitis (ID) or virulent footrot (VFR). The ovine interdigital skin bacterial community varied significantly by flock and clinical condition. The diversity and richness of operational taxonomic units was greater in tissue from sheep with ID than H or VFR-affected sheep. Actinobacteria, Bacteriodetes, Firmicutes and Proteobacteria were the most abundant phyla comprising 25 genera. Peptostreptococcus, Corynebacterium and Staphylococcus were associated with H, ID and VFR, respectively. Sequences of Dichelobacter nodosus, the causal agent of ovine footrot, were not amplified because of mismatches in the 16S rRNA universal forward primer (27F). A specific real-time PCR assay was used to demonstrate the presence of D. nodosus, which was detected in all samples including the flock with no signs of ID or VFR. Sheep with ID had significantly higher numbers of D. nodosus (104–109 cells per g tissue) than those with H or VFR feet.  相似文献   
129.
Climate change scenarios predict a doubling of the atmospheric CO2 concentration by the end of this century. Yet, how rising CO2 will affect the species composition of aquatic microbial communities is still largely an open question. In this study, we develop a resource competition model to investigate competition for dissolved inorganic carbon in dense algal blooms. The model predicts how dynamic changes in carbon chemistry, pH and light conditions during bloom development feed back on competing phytoplankton species. We test the model predictions in chemostat experiments with monocultures and mixtures of a toxic and non-toxic strain of the freshwater cyanobacterium Microcystis aeruginosa. The toxic strain was able to reduce dissolved CO2 to lower concentrations than the non-toxic strain, and became dominant in competition at low CO2 levels. Conversely, the non-toxic strain could grow at lower light levels, and became dominant in competition at high CO2 levels but low light availability. The model captured the observed reversal in competitive dominance, and was quantitatively in good agreement with the results of the competition experiments. To assess whether microcystins might have a role in this reversal of competitive dominance, we performed further competition experiments with the wild-type strain M. aeruginosa PCC 7806 and its mcyB mutant impaired in microcystin production. The microcystin-producing wild type had a strong selective advantage at low CO2 levels but not at high CO2 levels. Our results thus demonstrate both in theory and experiment that rising CO2 levels can alter the community composition and toxicity of harmful algal blooms.  相似文献   
130.
A class of glycolipopeptides for use as building blocks for a new type of dynamic combinatorial library is reported. The members of the library consist of a variable carbohydrate moiety, coded amino acids, and lipoamino acids in order to convert them into amphiphiles. Glycolipopeptidic amphiphiles interact through non-covalent bonding when mixed together in aqueous phase and form micelles in dynamic close-packed fluid mosaic arrays. The head groups of amphiphiles are exposed on the micelle surface, providing entities which could be screened in biological assays to find the most potent combination of building blocks in order to identify new bioactive carbohydrate ligands.  相似文献   
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