Engineering Isopropanol Dehydrogenase for Efficient Regeneration of Nicotinamide Cofactors.

Isopropanol dehydrogenase (IPADH) is one of the most attractive options for nicotinamide cofactor regeneration due to its low cost and simple downstream processing. However, poor thermostability and strict cofactor dependency hinder its practical application for bioconversions. In this study, we simultaneously improved the thermostability (433-fold) and catalytic activity (3.3-fold) of IPADH from Brucella suis via a flexible segment engineering strategy. Meanwhile, the cofactor preference of IPADH was successfully switched from NAD(H) to NADP(H) by 1.23 × 106-fold. When these variants were employed in three typical bioredox reactions to drive the synthesis of important chiral pharmaceutical building blocks, they outperformed the commonly used cofactor regeneration systems (glucose dehydrogenase [GDH], formate dehydrogenase [FDH], and lactate dehydrogenase [LDH]) with respect to efficiency of cofactor regeneration. Overall, our study provides two promising IPADH variants with complementary cofactor specificities that have great potential for wide applications. IMPORTANCE Oxidoreductases represent one group of the most important biocatalysts for synthesis of various chiral synthons. However, their practical application was hindered by the expensive nicotinamide cofactors used. Isopropanol dehydrogenase (IPADH) is one of the most attractive biocatalysts for nicotinamide cofactor regeneration. However, poor thermostability and strict cofactor dependency hinder its practical application. In this work, the thermostability and catalytic activity of an IPADH were simultaneously improved via a flexible segment engineering strategy. Meanwhile, the cofactor preference of IPADH was successfully switched from NAD(H) to NADP(H). The resultant variants show great potential for regeneration of nicotinamide cofactors, and the engineering strategy might serve as a useful approach for future engineering of other oxidoreductases.

Synchronous colorectal cancer and multiple myeloma with chest wall involvement: Is this a coincidence?

Multiple primary malignant neoplasms (MPMNs) are rare malignant neoplasms that simultaneously or successively occur in the same patient as 2 or more primary malignancies. Currently, an increasing number of cases are being reported. In general, MPMNs more commonly occur as 2 solid tumors or 2 hematological malignancies. Cases of MPMN that involve a solid tumor and a hematological malignancy are rare. Here, we report a case of synchronous colorectal cancer (CRC) and multiple myeloma (MM) with chest wall involvement. After reviewing the literature, we believe that there may be a distinct syndrome involving CRC and MM. The patient in our case study suffered refractory anemia following surgery and 2 cycles of chemotherapy. Initially, the anemia was considered to be a common manifestation of CRC in this patient. Interestingly, although he received a blood transfusion, his hemoglobin levels remained low. He later developed hematuria, proteinuria, multiple osteoporosis in the costal bones, and thrombocytopenia. These new symptoms drew our attention, and we considered a diagnosis of synchronous primary CRC and MM, with the anemia as a symptom of MM. Based on the results of a bone marrow aspirate, MM was confirmed. Therefore, when CRC is associated with refractory anemia, we should not only assume that anemia is a classical symptom of CRC, a result of chronic blood loss, nutritional deficiencies, or myelosuppression due to chemotherapy, but we should also consider that it may reflect the possibility of a coexisting hematologic malignancy. As the treatment of these 2 malignancies is different, early diagnosis and treatment based on definitive diagnosis as early as possible will be beneficial to overall prognosis.

Effects of tai chi program on neuromuscular function for patients with knee osteoarthritis: study protocol for a randomized controlled trial.

BACKGROUND: Knee osteoarthritis (OA) is a major cause of disability as well as a burden on healthcare resources. Tai chi has been proposed as an alternative and complementary treatment for the management of knee osteoarthritis, but there appears to be no consensus on its usefulness. This study aims to develop an innovative tai chi rehabilitation program (ITCRP) for patients with knee OA, and to investigate the effect of ITCRP intervention on a range of outcomes including pain, function, balance, neuromuscular response, and biomechanics in knee OA. METHODS/DESIGN: We will conduct a prospective, single-blind, randomized controlled trial of 140 individuals with symptomatic knee OA. Patients will be randomly assigned into either an ITCRP group or a control group. The ITCRP group will participate in tai chi two or three times a week for 6 months. The control group will receive health education. After the 6-month intervention period, there will be a 6-month follow-up period with no active intervention in either group. The primary and secondary outcomes will be assessed at baseline, 6 months, and 12 months. Primary outcome measures will be a visual analog scale for pain, the Western Ontario and McMaster Universities Osteoarthritis Index,and the Lequesne Knee Score. The secondary outcome measures will include the Berg balance scale, knee and ankle proprioception, neuromuscular response, and 3D functional biomechanics. Furthermore, adverse events will be recorded and analyzed. If any participants withdraw from the trial, intention-to-treat analysiswill be performed. DISCUSSION: Important features of this trial include the randomization procedures, large sample size, and a standardized protocol for ITCRP for knee OA. This study aims to determine the feasibility of ITCRP for knee OA and provide data on the effects of ITCRP. Hence, our results will be useful for patients with knee OA as well as for medical staff and healthcare decision makers. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR-TRC-13003264.