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Introduction: Tactical Combat Casualty Care (TCCC) training imposes psychophysiological stress on medics. It is unclear whether these stress levels vary with the training modalities selected. It is also unclear how stress levels could have an impact on medical performance and skill uptake.Materials and Methods: We conducted a pilot study to compare the effects of live tissue (LT) with a high-fidelity patient simulator (SIM) on the level of stress elicited, performance, and skill uptake during battlefield trauma training course in an operating room (OR) and in a simulated battlefield scenario (field). In the report, we studied the effects of training modalities and their changes on stress levels by measuring different biomarkers (salivary amylase, plasma catecholamines, and neuropeptide Y) at various time points during the trauma training course.Results: We found that the training resulted in significant psychophysiological stress as indicated by elevated levels of various biomarkers relative to baseline immediately after both OR and field assessment (p < 0.05). Compared with pre-OR levels, the LT training in the OR resulted in significant increases in the plasma levels of epinephrine, norepinephrine, and neuropeptide (p = 0.013, 0.023, 0.004, respectively), whereas the SIM training in the OR resulted in significant increases in the plasma levels of norepinephrine and neuropeptide (p = 0.003 and 0.008). Compared with pre-field levels, we found significant increases in plasma epinephrine concentration in the SIM group (p = 0.016), plasma norepinephrine concentration in the LT group (p = 0.015), and plasma neuropeptide Y concentration in both LT (p = 0.006) and SIM groups (p = 0.029). No differences in the changes of biomarker levels were found between LT and SIM groups in the OR and field. Compared with pre-field levels, the testing on the same modality as that in the OR in the simulated battlefield resulted in significant increases in norepinephrine and neuropeptide levels (p = 0.013 and 0.015), whereas the testing on different modalities resulted in significant increases in amylase, epinephrine, and neuropeptide levels (p = 0.016, 0.05, 0.018, respectively). There was a significantly larger increase in plasma norepinephrine concentration (p = 0.031) and a trend toward a greater increase in the salivary amylase level (p = 0.052) when the field testing involved a different modality than the OR compared with when OR and field testing involved the same modality. Although most of the biomarkers returned to baseline levels after 24 h, plasma norepinephrine levels remained significantly higher regardless of whether field testing occurred on the same or different modality compared with OR (p = 0.040 and 0.002).Conclusion: TCCC training led to significant increase in psychophysiological stress, as indicated by elevated levels of various biomarkers. The training modalities did not result in any differences in stress levels, whereas the switch in training modalities appeared to elicit greater stress as evidenced by changes in specific biomarkers (amylase and norepinephrine). A comparative study with a larger sample size is warranted. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the role of miR-29a in regulating the differentiation mesenchymal stem cells into osteoblasts. MATERIALS AND METHODS: For the first step, the changes of expression of miR-29a during the process of mesenchymal stem cells (MSCs) differentiation into osteoblast were detected. Then, we infected the MSCs with mimics or inhibitors of miR-29a to explore the roles of miR-29a in the differentiation. Further, the prediction and verification of the possible target genes of miR-29a were achieved by bioinformatics analysis and luciferase reporter assay. RESULTS: MiR-29a was up-regulated during the process of MSCs differentiation into osteoblasts. Overexpression or inhibition of miR-29a using mimics or inhibitors had no significant effect on cell proliferation. Furthermore, the differentiation was enhanced when miR-29a was artificially overexpressed in vitro, whereas silencing of miR-29a attenuated this process. It was evidenced by alkaline phosphatase (ALP) staining, matrix mineralization, and increased expression of osteoblast-specific genes. Furthermore, we determined that the gene HDAC4 might be a direct target of miR-29a. CONCLUSIONS: In the current study, miR- 29a promotes osteogenesis via suppressing HDAC4, indicating that targeting miR-29a may be feasible in the management of osteoporosis. [ABSTRACT FROM AUTHOR]

A modified normalization method is presented for obtaining crack tip opening displacement (CTOD) resistance curves of single edge-notched tension specimens. For the applied load mode, the normalization method should be based on force-crack mouth opening displacement. A formula is proposed for CLL(i), the core parameter used in the normalization calculation. The modified method is validated using the unloading compliance method. The study of specimen geometry shows that side-groove depth and crack depth have significant impacts on the obtained CTOD resistance curves, and the shape of the crack front affects the determination accuracy of crack length. [ABSTRACT FROM AUTHOR]

Introduction These recommendations are intended to develop a consensus in the previously published papers as to which parameters and what values should be considered critical. A practical guide on the standardization of critical results management in haematology laboratories would be beneficial as part of good laboratory and clinical practice and for use by laboratory-accrediting agencies. Methods A working group with members from Europe, America, Australasia and Asia was formed by International Council for Standardization in Haematology. A pattern of practice survey of 21 questions was distributed in 2014, and the data were collected electronically by Survey Monkey. The mode, or most commonly occurring value, was selected as the threshold for the upper and lower alert limits for critical results reporting. Results A total of 666 laboratories submitted data to this study and, of these, 499 submitted complete responses. Full blood count critical results alert thresholds, morphology findings that trigger critical result notification, critical results alert list, notification process and maintenance of critical results management protocol are described. This international survey provided a snapshot of the current practice worldwide and has identified the existence of considerable heterogeneity of critical results management. Conclusion The recommendations in this study represent a consensus of good laboratory practice. They are intended to encourage the implementation of a standardized critical results management protocol in the laboratory. [ABSTRACT FROM AUTHOR]

Hypopituitarism in leukemia is very rare. In addition, central nervous system (cns) relapse and leukemic retinopathy in childhood acute lymphoblastic leukemia (all) have declined with the use of modern systemic chemotherapy that includes cns prophylaxis. Here, we report the case of a 4-year-old girl who received chemotherapy and intrathecal therapy without cns radiation after a diagnosis of B-precursor all without cns involvement. Three months after chemotherapy completion, she presented with lower-extremity weakness and was diagnosed with an isolated cns relapse. Concurrent hypopituitarism and leukemic retinopathy were also found. After receiving craniospinal radiotherapy and systemic chemotherapy, her retinopathy and vision improved. She is now in complete remission, and she is still on chemotherapy according to the guideline from the Pediatric Oncology Group. Although rare, hypopituitarism and leukemic retinopathy should be taken into consideration in patients with cns involvement by leukemia. [ABSTRACT FROM AUTHOR]

Hyperbaric and decompression stress from diving impairs blood coagulation and fibrinolysis. We hypothesized that thromboelastography (TEG) and rotational thromboelastometry (ROTEM) were suitable to characterize the effects of stress on global hemostatic profiles. We thus conducted a comparative study of the hyperbaric effects on human coagulation using TEG and ROTEM. Maximum clot strength (maximum amplitude [MA]) and clot lysis (lysis index at time 30 minutes [LI30]) were reduced as indicated by TEG MA and EXTEM LI30, respectively. The relative changes in coagulation and fibrinolysis by the hyperbaric effects of diving were indicated by reduced TEG reaction time R at 5 hours, MA at 24 hours postdive, and reduced EXTEM coagulation time at 15 minutes postdive as well as decreased fibrinolysis (EXTEM LI30) at all postdiving time points investigated. Comparison of the parameter values and the diving-induced changes in each parameter between TEG and ROTEM showed both differences and correlations. The discrepancies between the 2 systems may be due to the different assay reagents used. Future studies will seek to further elucidate the changes in blood coagulation and fibrinolysis following varying levels of hyperbaric and decompression stress. [ABSTRACT FROM AUTHOR]

The oxidation of ammonia by microbes and associated organisms has been shown to occur in diverse natural environments. However, the contribution of ammonia-oxidizing archaea to nitrification in high-temperature environments remains unclear. Here, we studied in situ ammonia oxidation rates and the abundance of ammonia-oxidizing archaea (AOA) in surface and bottom sediments at 77 °C in the Gongxiaoshe hot spring, Tengchong, Yunnan, China. The in situ ammonia oxidation rates measured by the 15N-NO3- pool dilution technique in the surface sinter and bottom sediments were 4.8 and 5.3 nmolNg-1 h-1, respectively. Relative abundances of Crenarchaea in both samples were determined by fluorescence in situ hybridization (FISH). Phylogenetic analysis of 16S rRNA genes showed high sequence similarity to thermophilic "Candidatus Nitrosocaldus yellowstonii", which represented the most abundant operation taxonomic units (OTU) in both sediments. Furthermore, bacterial amoA was not detected in this study. Quantitative PCR (qPCR) indicated that AOA and 16S rRNA genes were present in the range of 2.75 to 9.80×105 and 0.128 to 1.96×108 genecopiesg-1 sediment. The cell-specific nitrification rates were estimated to be in the range of 0.41 to 0.79 fmolNarchaeal cell-1 h-1, which is consistent with earlier estimates in estuary environments. This study demonstrated that AOA were widely involved in nitrification in this hot spring. It further indicated the importance of archaea rather than bacteria in driving the nitrogen cycle in terrestrial geothermal environments. [ABSTRACT FROM AUTHOR]