Translation of foot-and-mouth disease virus RNA: factors influencing alternative AUG selection.

The mechanism of alternative AUG usage in foot-and-mouth disease virus is not completely understood. Using simple computational approaches, we evaluated the contributions of overall codon bias, quantitative codon bias, and %GC of the region between the two alternative AUGs, Region-La, as well as the nucleotide bias of the sequence context flanking each AUG with respect to translation initiation efficiency. For all serotypes of this virus, we found that only a small component of the effect of RNA secondary structure on ribosome scanning was due to the low %GC of Region-La. In addition, we found that the nucleotide bias of the context from position -4 to +6 flanking the AUG(2nd) had a negative correlation with the overall codon bias, and that a strong purine bias existed in this AUG(2nd)context. However, the quantitative codon bias of Region-La was seen to be significantly lower than that of Region-Lb (the sequence following AUG(2nd)) in all serotypes except SAT 1-3. Taken together, our results suggest that the low codon bias of Region-La might impair the translation initiation efficiency at the AUG(1st) in all serotypes except SAT 1-3, and the specific AUG(2nd) context might be used as a strong signal to initiate translation from the AUG(2nd) in all serotypes.

Effect of Repeated Recruitment Manoeuvres on Patients with Severe Acute Respiratory Distress Syndrome.

OBJECTIVE: The study aimed to evaluate the influence of repeated recruitment manoeuvres (RRMs) on lung injury in patients with acute respiratory distress syndrome (ARDS). METHODS: Forty-one ventilated patients with severe ARDS were selected for this study. Recruitment manoeuvres (RMs) were conducted with continuous positive airway pressure (CPAP; 30 cm H2O for 40 seconds). Recruitment manoeuvres were repeated every two hours for all three groups. Changes in haemodynamics, pulmonary compliance, gas exchange and extravascular lung water index (EVLWI) were monitored before RM (pre-RM), 10 minutes after each RM, and four hours after RM3 (4 hours post-RRM). Pulmonary inflammatory factors (tumour necrosis factor-alpha [TNF-α] and interleukin [IL]-6 and -10) were also analysed. RESULTS: Compared with those in pre-RM, pulmonary compliance, oxygenation index (ratio of partial pressure of arterial oxygen to fraction of inspired oxygen [PaO2/FiO2]) and EVLWI remarkably improved in RM1, RM2, RM3 and 4 hours post-RRM (p < 0.05). The PaO2/FiO2 ratio increased significantly in RM1 and RM3 (p < 0.05). Extravascular lung water index decreased significantly in RM1 compared with that in RM3 and 4 hours post-RRM (p < 0.05). There was no significant difference in cytokines. CONCLUSION: Repeated recruitment manoeuvres during lung-protected ventilation can improve pulmonary compliance and oxygenation and significantly decrease extravascular lung water in ARDS patients. Lung injury was not worsened by RRMs in patients with severe ARDS.

Cloning and expression analysis of a stress-induced GmIMT1 gene in soybean (Glycine max).

Here, we aimed to clone and identify the GmIMT1 gene related to the salt stress response in soybean. The full-length cDNA sequence of the GmIMT1 gene was amplified in soybean using degenerate primers of Mesembrythmum crystallium. To understand the stress response, the GmIMT1 gene was cloned and sequenced. Then, the expression vectors of the gene were constructed, and introduced into the model plant Arabidopsis thaliana through Agrobacterium mediated transformation, and the salt tolerance was analyzed in the transgenic plants. In addition, the expression patterns of GmIMT1 gene in soybean were analyzed. The expression was examined in different organs (roots, leaves, flower seeds, and stem) and under different stress conditions (drought, high salt, low temperature, salicylic acid, ethane, abscisic acid, and methyl jasmonate) by real-time fluorescent quantitative polymerase chain reaction analysis. The results showed that the root, leaves, and stems exhibited high level of GmIMT1 gene expression, whereas there was no expression in the seeds. In addition, the GmIMT1 gene expression was upregulated under all stress conditions. Overall, the results clearly indicate that GmIMT1 might be involved in multiple plant response pathways to the different environmental conditions. Furthermore transgenic plants exhibited higher salt-tolerance compared to wild type plants.