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81.
Introduction
The effect of hemoglobin levels on the weaning outcomes of mechanically ventilated patients remains under debate, particularly for the patients with difficult weaning. This study aims to evaluate the effect of hemoglobin levels on weaning outcomes in difficult-to-wean patients.Methods
This retrospective cohort study was conducted in a university-affiliated teaching hospital in Taiwan. Patients who fulfilled the criteria of difficult weaning were enrolled. Medical records were reviewed to obtain data on hemograms, biochemistry tests, transfusion records, comorbidities and weaning outcome. The association between hemoglobin levels and 30-day weaning outcomes was evaluated using a logistic regression model.Results
A total of 751 patients received mechanical ventilation during the study period, 138 of whom fulfilled the criteria of difficult weaning. Compared with the patients whose hemoglobin was <8 g/dL, those with higher hemoglobin levels were more likely to be successfully weaned (odds ratio [OR], 3.69; 95% CI, 1.22–11.15 for hemoglobin 8–10 g/dL and OR, 4.16, 95% CI, 1.30–13.29 for hemoglobin >10 g/dL). Multivariate analysis showed that the odds ratio for weaning success remained significant for hemoglobin levels of 8–10 g/dL (adjusted OR, 3.3; 95% CI, 1.07–10.15) with borderline significance for hemoglobin level > 10 g/dL (adjusted OR, 2.95, 95% CI, 0.88–9.96).Conclusions
Hemoglobin level is independently associated with weaning outcome in difficult-to-wean patients. Further studies are needed to evaluate whether a restrictive transfusion trigger for acute critical illness is also appropriate for such patients. 相似文献82.
Formaldehyde (FA) is frequently used in sterilizing surgical instruments and materials. Exposure to FA is highly concerned for eye tissues. Rabbit corneal epithelial cells were examined for changes after FA exposure. Our results showed that cell survival decreased 7 days after transient 3 min exposure to more than 100 ppm FA by trypan blue staining while MTT assay detected significant decrease at 20 ppm at 24 hours observation. The decrease of cell survival rate was concentration (up to 600 ppm)- and observation time (1–7 day)- dependent. The cell number decreased after 100 ppm FA exposure for more than 10 min at 7-day observation. The FA treated cells showed increased apoptosis/necrosis and cell cycle accumulation at sub G1 phase as well as mitochondria clustering around nucleus. The in vivo rabbit eye exposure for tear production by Schirmer’s test revealed that the FA-induced overproduction of tear also exhibited observation time (1–10 day)- and FA concentration (20–300 ppm for 5 min exposure)-dependent. Activated extracellular signal-regulated kinase (pERK2) in cornea explants by western blotting was reduced and increased c-Jun amino - terminal kinase (JNK) activation (pJNK) in cornea and conjunctiva was evident at 2 month after exposure to 50–200 ppm FA for 5 min. In conclusion, injury to the eye with transient exposure of up to 100 ppm FA for 3 min decreased corneal cell survival while a more sensitive MTT test detected the cell decrease at 20 ppm FA exposure. Morphology changes can be observed even at 5 ppm FA exposure for 3 min at 7 days after. The FA exposure also increased apoptotic/necrotic cells and sub-G1 phase in cell cycle. Long term effect (2 months after exposure) on the eye tissues even after the removal of FA can be observed with persistent JNK activation in cornea and conjunctiva. 相似文献
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Several chiral ligands containing (R,R)‐diaminocyclohexane moieties and pyrrole, furan, or benzene have been synthesized. These ligands were tested in enantioselective zinc‐catalyzed hydrosilylation reactions; excellent enantioselectivities were obtained when the ligands containing (R,R)‐diaminocyclohexane moieties and furan rings were used. For comparison, zinc chloride combined with different potassium carboxylate salts and ligands were also tested for catalytic hydrosilylation reactions. Chirality 25:275–280, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
86.
S. Lai L. G. Gillis C. Mueller T. J. Bouma J. R. Guest K. S. Last A. D. Ziegler P. A. Todd 《Coral reefs (Online)》2013,32(4):1061-1064
We present the first experimental evidence of a coral (Oulastrea crispata) ingesting and assimilating seagrass material. Tropical seagrass meadows export a substantial portion of their productivity and can provide an important source of nutrients to neighbouring systems such as coral reefs; however, little is known about the mechanisms of this link. To investigate whether seagrass nutrient uptake via coral heterotrophy is possible, we conducted a feeding experiment with seagrass particulate and dissolved organic matter. Using gut extractions and stable isotope analyses, we determined that O. crispata ingested 15N-enriched seagrass particles and assimilated the nitrogen into its tissue at a rate of 0.75 μg N cm?2 h?1. Corals took up nitrogen from dissolved matter at a comparable rate of 0.98 μg N cm?2 h?1. While other ecological connections between seagrass meadows and reef ecosystems are well known, our results suggest a previously unstudied direct nutritional link between seagrasses and corals. 相似文献
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Feng-Jung Chen Kuan-Wei Lee Chun-Chieh Lai Sue-Ping Lee Hsiao-Hsuian Shen Shu-Ping Tsai Bang-Hung Liu Ling-Mei Wang Gunn-Guang Liou 《Biochemical and biophysical research communications》2013
Receptor tyrosine kinases (RTKs) regulate many cellular processes, and Sprouty2 (Spry2) is known as an important regulator of RTK signaling pathways. Therefore, it is worth investigating the properties of Spry2 in more detail. In this study, we found that Spry2 is able to self-assemble into oligomers with a high-affinity KD value of approximately 16 nM, as determined through BIAcore surface plasmon resonance analysis. The three-dimensional (3D) structure of Spry2 was resolved using an electron microscopy (EM) single-particle reconstruction approach, which revealed that Spry2 is donut-shaped with two lip-cover domains. Furthermore, the method of energy dispersive spectrum obtained through EM was analyzed to determine the elements carried by Spry2, and the results demonstrated that Spry2 is a silicon- and iron-containing protein. The silicon may contribute to the electroconductivity of Spry2, and this property exhibits a concentration-dependent feature. This study provides the first report of a silicon- and iron-containing protein, and its 3D structure may allow us (1) to study the potential mechanism through the signal transduction is controlled by switching the electronic transfer on or off and (2) to develop a new type of conductor or even semiconductor using biological or half-biological hybrid materials in the future. 相似文献
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