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91.
A single‐use flexible bronchoscope with a large suction channel has become available recently and we have evaluated this innovative device. Firstly, bronchoalveolar lavage was performed and quantified in ventilated piglets. Next, the bronchoscope was evaluated in three intensive care units and a satisfaction questionnaire was carried out. Sixteen bronchoalveolar lavages were performed in piglets with a recovery rate of 83 (79–86 [72–89])% of the instilled volume. Quality and performance of all devices tested was identical. The medical satisfaction questionnaire was as follows: ‘acceptable’ to ‘very good’ for quality of aspiration, manoeuvrability and quality of vision; ‘very good’ to ‘perfect’ for setting up and insertion. This encouraging preliminary evaluation demonstrates the effectiveness of this new single‐use device, which may obviate the need for disinfection procedures and, thereby, eradicate a potential vector of patient cross‐contamination.  相似文献   
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Background

Lactoferrin (LF) is a pleiotropic glycoprotein that is found in bodily secretions and is postulated to enhance the gastrointestinal barrier and promote mucosal immunity. Thus, the ability of talactoferrin, an oral recombinant form of human LF, to limit gut injury and the production of biologically active gut-derived products was tested using a rat model of trauma–hemorrhagic shock (T/HS).

Methods

Male rats were orally dosed with vehicle or talactoferrin (1000 mg/kg, every day) for 5 d before being subjected to T/HS or trauma–sham shock (T/SS). Subsequently, rats were subjected to a laparotomy (trauma) and hemorrhagic shock (mean arterial pressure, 30–35 mm Hg × 90 min) or to T/SS, followed by resuscitation with their shed blood. Before inducing shock, the mesenteric lymphatic duct was catheterized for collection of mesenteric lymph. Four hours after the end of the shock or sham-shock period, rats were sacrificed, a segment of the distal ileum was collected for morphologic analysis, and lymph samples were processed and frozen. Subsequently, lymph samples were tested in several pharmacodynamic assays, including endothelial cell permeability, neutrophil respiratory burst activity, and red blood cell (RBC) deformability. Total white blood cell counts in lymph samples were also quantified.

Results

Pretreatment with talactoferrin reduced the incidence of T/HS-induced morphologic injury of ileum to T/SS levels. Post-T/HS lymph from vehicle-treated rats increased endothelial monolayer permeability and neutrophil priming for an augmented respiratory burst, and induced loss of RBC deformability, compared with T/SS groups. Talactoferrin pretreatment significantly reduced the biological activity of T/HS lymph on respiratory burst activity and RBC deformability, but had no effect on the lymph cell count or endothelial cell permeability.

Conclusions

These results provide a proof of principle that prophylactic dosing of oral talactoferrin can potentially protect the gut in a T/HS model and limit the production of biologically active factors in rat gastrointestinal tissue subjected to ischemia-reperfusion–type injuries.  相似文献   
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Introduction

Alcohol use is an important contributor to injuries. Simple bedside tools to identify trauma patients with potentially harmful drinking may assist in brief intervention efforts in clinical practice. The objective of the study was to determine and compare the accuracy of alcohol use disorders identification test (AUDIT) and an abbreviated version of this test, in the detection of hazardous drinking.

Methods

A cross-sectional study of a convenience sample of admitted trauma patients at a single Australian major trauma centre. Eligible patients completed the AUDIT. AUDIT survey responses were scored in two ways, using the full form scale and secondly an abbreviated (AUDIT C) scale which uses only the first 3 questions. AUDIT and AUDIT-C scores were then evaluated with respect to the primary study measure; the detection of hazardous alcohol consumption based on a full alcohol consumption history. Sensitivities for each relevant score were calculated and receiver operator characteristic (ROC) curve analysis was used to determine test accuracy.

Results

During the study period, 523 trauma admissions were identified and of these 146 (28%) were screened. The optimum cut off scores for AUDIT and AUDIT-C were 8 and 5 respectively corresponding to sensitivities of 88% and 91% and both tests had excellent overall accuracy for the detection of hazardous alcohol consumption. There was no significant difference between AUDIT-C and AUDIT performance (p = 0.395) (AUDIT-C AUROC 0.96 95%CI 0.93, 0.99).

Conclusion

AUDIT-C appears to be a potentially useful screening tool for use trauma centres, but that further research with larger samples is required.  相似文献   
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Background

Early fetuses heal wounds without the formation of a scar. Many studies have attempted to explain this remarkable phenomenon. However, the exact mechanism remains unknown. Herein, we examine the predominant cell types of the epidermis and dermis—the keratinocyte and fibroblast—during different stages of fetal development to better understand the changes that lead to scarring wound repair versus regeneration.

Materials and methods

Keratinocytes and fibroblasts were harvested and cultured from the dorsal skin of time-dated BALB/c fetuses. Total RNA was isolated and microarray analysis was performed using chips with 42,000 genes. Significance analysis of microarrays was used to select genes with >2-fold expression differences with a false discovery rate <2. Enrichment analysis was performed on significant genes to identify differentially expressed pathways.

Results

By comparing the gene expression profile of keratinocytes from E16 versus E18 fetuses, we identified 24 genes that were downregulated at E16. Analysis of E16 and E18 fibroblasts revealed 522 differentially expressed genes. Enrichment analysis showed the top 20 signaling pathways that were downregulated in E16 keratinocytes and upregulated or downregulated in E16 fibroblasts.

Conclusions

Our data reveal 546 differentially expressed genes in keratinocytes and fibroblasts between the scarless and scarring transition. In addition, a total of 60 signaling pathways have been identified to be either upregulated or downregulated in these cell types. The genes and pathways recognized by our study may prove to be essential targets that may discriminate between fetal wound regeneration and adult wound repair.  相似文献   
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