9α-hydroxy-4-androstene-3,17-dione (9-OH-AD) is an important intermediate in the steroidal drugs production. 3-ketosteroid-9α-hydroxylase (KSH), a two protein system of KshA and KshB, is a key-enzyme in the microbial steroid ring B-opening pathway. KSH catalyzes the transformation of 4-androstene-3,17-dione (AD) into 9-OH-AD specifically. In the present study, the putative KshA and KshB genes were cloned from Mycobacterium smegmatis mc(2)155 and Gordonia neofelifaecis NRRL B-59395 respectively, and were inserted into the expression vector pNIT, the co-expression plasmids of kshA-kshB were obtained and electroporated into Mycobacterium sp. NRRL B-3805 cells. The recombinants were used to transform steroids, the main product was characterized as 9α-hydroxy-4-androstene-3,17-dione (9-OH-AD), showing that kshA and kshB were expressed successfully. Different from the original strain Mycobacterium sp. NRRL B-3805 that accumulates 4-androstene-3,17-dione, the recombinants accumulates 9α-hydroxy-4-androstene-3,17-dione as the main product. This results indicates that the putative genes kshA, kshB encode active KshA and KshB, respectively. The process of biotransformation was investigated and the results show that phytosterol is the most suitable substrate for biotransformation, kshA and kshB from M. smegmatis mc(2)155 seemed to exhibit high activity, because the resultant recombinant of them catalyzed the biotransformation of phytosterol to 9-OH-AD in a percent conversion of 90%, which was much higher than that of G. neofelifaecis NRRL B-59395. This study on the manipulation of the ksh genes in Mycobacterium sp. NRRL B-3805 provides a new pathway for producing steroid medicines.
Androstenedione ; analogs & derivatives ; biosynthesis ; Bacterial Proteins ; genetics ; metabolism ; Biotransformation ; Ketosteroids ; Mixed Function Oxygenases ; genetics ; metabolism ; Mycobacterium ; metabolism ; Mycobacterium smegmatis ; enzymology ; Plasmids

Objective: To observe the efficacy and safety of CTD (cyclophosphamide, thalidomide, dexamethasone) and PCD (bortezomib, cyclophosphamide, dexamethasone) regimens in treatment of patients with newly diagnosed multiple myeloma (NDMM) . Methods: A retrospective analysis was carried out on 88 cases of NDMM patients admitted to our hospital from July 2013 to January 2016, including 49 cases in CTD group and 39 cases in PCD group. The outcomes of two different regimens were analyzed, including response, prognosis, and adverse events. Results: The total overall remission rates (ORR, better than PR) of CTD and PCD were 65.3% (32/49) and 84.6% (33/39) , while very good partial response (VGPR) were 30.6% (15/49) and 53.8% (21/39) , and differences were statistically significant (P=0.041, P=0.028) . The median follow-up was 11.5 (3-33) months. The median progression-free survival (PFS) was (23.0±4.5) months in CTD groups, but it was not achieved in PCD group, with statistically significant differences (P=0.050) . Medial overall survival was not achieved in both two groups, without statistically significant difference (P=0.257) . There were statistical differences between patients with minor response (MR) and patients without MR in medium OS in CTD group (P=0.005) , and there were statistical difference between patients with VGPR and without VGPR in medium OS in CTD group (P=0.042) . Infection was a common adverse event in two groups. The incidences of peripheral neuropathy and herpes zoster were markedly higher in PCD group than CTD group, and the incidences of thrombus, palpation and rash, etc., were higher in CTD group. Conclusion Both CTD and PCD regimens were effective first-line induction chemotherapy choice for NDMM. PCD regimen is better than CTD in treatment power and deep remission.

Objective    To investige the effects of multidisciplinary perioperative nutrition management on nutrition and postoperative complications of patients with esophageal cancer. Methods    A total of 239 patients with esophageal cancer who received elective surgical treatment were included in the study. They were divided into a trial group (120 patients) and a control group (119 patients) according to the random number table method. There were 97 males and 23 females in the trial group with an average age of 63.78±9.13 years, and 94 males and 25 females in the control group with an average age of 64.12±7.91 years. The control group received routine diet management, and the trial group received multidisciplinary perioperative nutrition management. The differences of nutrition and postoperative complications between the two groups were compared. Results    The total protein and albumin levels on postoperative days 3 and 7 in the trial group were higher than those in the control group (P<0.05), patients' postoperative anal exhaust time was shorter than that in the control group (P<0.05), the incidence of postoperative gastrointestinal adverse reactions, lung infection, postoperative anastomotic fistula, hypoproteinemia on postoperative days 3 and 7 was lower than that in the control group (P<0.05), and hospitalization cost was lower than that in the control group (P<0.05). Conclusion    Multidisciplinary nutrition management can effectively improve the nutrition of patients, promote the rapid recovery of postoperative gastrointestinal function, reduce postoperative complications, and reduce hospitalization costs. It has high clinical reference and promotion value.