A novel esterase gene (estSL3) was cloned from the Alkalibacterium sp. SL3, which was isolated from the sediment of soda lake Dabusu. The 636-bp full-length gene encodes a polypeptide of 211 amino acid residues that is closely related with putative GDSL family lipases from Alkalibacterium and Enterococcus. The gene was successfully expressed in E. coli, and the recombinant protein (rEstSL3) was purified to electrophoretic homogeneity and characterized. rEstSL3 exhibited the highest activity towards pNP-acetate and had no activity towards pNP-esters with acyl chains longer than C8. The enzyme was highly cold-adapted, showing an apparent temperature optimum of 30 °C and remaining approximately 70% of the activity at 0 °C. It was active and stable over the pH range from 7 to 10, and highly salt-tolerant up to 5 M NaCl. Moreover, rEstSL3 was strongly resistant to most tested metal ions, chemical reagents, detergents and organic solvents. Amino acid composition analysis indicated that EstSL3 had fewer proline residues, hydrogen bonds and salt bridges than mesophilic and thermophilic counterparts, but more acidic amino acids and less hydrophobic amino acids when compared with other salt-tolerant esterases. The cold active, salt-tolerant and chemical-resistant properties make it a promising enzyme for basic research and industrial applications.

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Anesthetic management for patients with a giant emphysematous bulla (GEB) is challenging. This case report describes a patient who developed 95% pulmonary compression by a GEB. A 14-Ga indwelling catheter was placed in the GEB before surgery to allow for slow re-expansion of the collapsed lung tissue. This prevented rupture of the GEB during anesthesia. Additionally, positive-pressure ventilation was performed to reduce the risk of re-expansion pulmonary edema. This respiratory management strategy may be beneficial for patients with a GEB who develop pulmonary dysfunction during thoracic surgery.

Introduction: Severe ischemia is a rare complication of radial artery catheterization (RAC). This study aims to summarize risk factors of RAC-elicited severe hand ischemia, preventive, and therapeutic management. Methods: Literature search was conducted in eight electronic English and Chinese databases to identify relevant published cases. Data of interest was extracted and analyzed. Results: Database search identified 28 articles reporting cases of 57 patients developing hand ischemia following RAC. Patients aged between 1 day and 88 years. The indications for RAC included surgery, shock, cardiac arrest, and Neonatal Intensive Care Unit (NICU) admission. Identified risk factors included pre-existing vascular diseases, hypotension, arterial anatomical abnormality or small diameter, vasoconstrictors, and catheter-related problems. Totally, 18 patients complained pain; 32 developed discoloration; 19 pulselessness; 3 paresthesia; 13 swolleness and 19 coldness. Eventually, 30 patients recovered well, but 20 patients unfortunately underwent digital amputation and three patients deceased due to non-RAC-related causes. Conclusion: Severe hand ischemia following RAC is a rare complication, with the reported incidence of approximately 0.09%. There is no definite predictor for RAC-related hand ischemia, but patients with risk factors are prone to the occurrence of hand ischemia. It’s vital to initiate early recognition and proactive strategies for a best practice RAC insertion.