This paper reports the progress of biodiesel production with enzymatic catalysis in Beijing University of Chemical Technology, one of the leaders in biodiesel R & D in China, which includes screening of high-yield lipase production strains, optimization and scale-up of the lipase fermentation process, lipase immobilization, bioreactor development and scale-up, biodiesel separation and purification and the by-product glycerol utilization. Firstly, lipase fermentation was carried out at industrial scale with the 5 m3 stirred tank bioreactor, and the enzyme activity as high as 8 000 IU/mL was achieved by the species Candida sp. 99-125. Then, the lipase was purified and immobilized on textile membranes. Furthermore, biodiesel production was performed in the 5 m3 stirred tank bioreactor with an enzyme dosage as low as 0.42%, and biodiesel that met the German biodiesel standard was produced. And in the meantime, the byproduct glycerol was used for the production of 1,3-propanediol to partly offset the production cost of biodiesel, and 76.1 g/L 1,3-propanediol was obtained in 30 L fermentor with the species Klebsiella pneumoniae.
Biofuels ; Bioreactors ; Biotechnology ; economics ; methods ; Candida ; enzymology ; Catalysis ; China ; Enzymes, Immobilized ; metabolism ; Esterification ; Fermentation ; Lipase ; metabolism ; Plant Oils ; chemistry

Objective:To explore the characteristics of BCR-ABL1 kinase domain mutations in imatinib-resistant chronic myelogenous leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) patients from Northeast China and their impact on prognosis. Methods:The clinical data of 252 CML patients and 49 Ph + ALL patients who were admitted to the First Hospital of Jilin University from January 2013 to October 2018 were retrospectively analyzed. The samples of bone marrow or peripheral blood were collected from patients when imatinib treatment was not effective. Nested polymerase chain reaction (PCR) was used to amplify the BCR-ABL1 kinase domain, and Sequencing Analysis v5.4 software was used to analyze the mutation of BCR-ABL1 kinase domain. Patients were followed up for 6-48 months, and the survival analysis was performed. Results:Among 252 CML patients, the mutations in ABL1 kinase domain were found in 57 patients (22.6%), including 25 patients in the chronic phase, 21 patients in the accelerated phase and 11 patients in the blast crisis; 50 patients had 20 types of single point mutation, and the most common mutation types were E255K (16.0%, 8/50), T315I (14.0%, 7/50), M244V (8.0%, 4/50) and G250E (8.0%, 4/50), which were all concentrated in the P-loop and C-helix domains; 7 patients had double mutations; patients with multiple mutations had the worst prognosis, with a median overall survival (OS) time of 3.2 months. Among 49 Ph + ALL patients, 17 cases (34.7%) were positive for mutations in the BCR-ABL1 kinase domain, 14 patients had 12 types of single point mutation, and 3 patients had multiple mutations; the median OS time of patients with multiple mutations, mutations located in the P-loop and C-helix domains and mutations located in the other domains was 2.0, 8.0 and 18.0 months, and the difference in OS among the three groups was statistically significant ( P < 0.01). Conclusions:Among the imatinib-resistant CML and Ph + ALL patients from Northeast China, point mutations in the P-loop and C-helix domains are most commonly found. Multiple mutations, mutations in the P-loop and C-helix domains are related to the poor prognosis of the patients.

Objective:To explore the efficacy and safety of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and human granulocyte colony-stimulating factor (G-CSF) for the prevention of post-chemotherapy infections in pediatric hematologic neoplasms.Methods:A total of 134 children hospitalized for chemotherapy in 6 tertiary hospitals from July 2016 to June 2018 were collected, including 60 cases in Children's Hospital of Fudan University, 38 cases in Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, 29 cases in Children's Hospital Affiliated to Soochow University, 4 cases in the Affiliated Hospital of Qingdao University, 2 cases in Northwestern Women and Children's Hospital, and 1 case in Shandong Provincial Qianfoshan Hospital. The children were divided into GM-CSF group (38 cases), G-CSF group (45 cases) and GM-CSF+G-CSF group (51 cases) by using random number table method. The incidence of infections, the recovery time of absolute neutrophil counting (ANC), the decrease of blood platelet count (Plt) and the incidence of adverse reactions were compared among the three groups.Results:In all children, a total of 64 cases (47.8%) had infections during the myelosuppression phase after chemotherapy, of which 18 cases (47.4%) in GM-CSF group, 20 cases (44.4%) in G-CSF group, and 26 cases (51.0%) in GM-CSF+G-CSF group. The incidence of respiratory infection in G-CSF group was higher than that in GM-CSF group and GM-CSF+ G-CSF group [22.2% (10/45) vs. 2.6% (1/38), 4.0% (2/51), χ2 = 12.00, P = 0.002]. The median time to recovery of ANC > 1.5×10 9/L was 10.5 d (8 d, 15 d) in all children, 12 d (10 d, 16 d) in GM-CSF group, 9 d (8 d, 12 d) in G-CSF group, and 10 d (8 d, 16 d) in GM-CSF+G-CSF group. In all children, a total of 101 cases (75.4%) had Plt<50×10 9/L during the myelosuppression phase, and 79 cases (59.0%) had Plt <20×10 9/L. The differences in the incidence of Plt <50×10 9/L and <20×10 9/L among the three groups were not statistically significant (both P > 0.05). In all children, the adverse reactions occurred in 24 cases (17.9%), including 20 cases (14.9%) of fever, 2 cases (1.5%) of sore throat, 1 case (0.7%) of nausea, and 1 case (0.7%) of diarrhea; no adverse reactions of grade 2 or above occurred. The difference in the incidence of adverse reactions among the three groups was not statistically significant ( P>0.05). Conclusions:The efficacy of GM-CSF and G-CSF for the prevention of infections in pediatric hematologic neoplasms during the myelosuppression phase after chemotherapy is roughly equivalent, and combination of both has a good tolerance. The incidence of respiratory infection using GM-CSF alone or GM-CSF+G-CSF is low, which might benefit from the effect of GM-CSF on lung infections.

We investigated the prevalence and genetic variation of porcine pseudorabies virus(PRV)in Hunan Province.A total of 18 861 serum samples and 1 725 suspected PRV-infected tissue sam-ples were collected from Hunan Province from 2021 to 2022.ELISA and qPCR assays were used to detect PRV-gE antibodies in serum samples and the PRV-gE nucleic acids in tissue samples.The positive rates of samples in different years and seasons were analyzed correspondingly.Moreover,the gC gene sequences of 15 PRV-positive samples were amplified,sequenced,and analyzed.The results showed that 2 004 serum and 56 tissue samples tested positive,with an average positive rate of 10.74％and 3.25％,respectively.The sequence analysis showed that the nucleotide and ami-no acid sequence identities of the gC gene among 15 PRV-positive samples were 98.4％-100.0％and 98.8％-100.0％,respectively.Further genetic evolution analysis showed that 13 PRV strains belonged to the same branch with the PRV variants,while two strains were clustered into the same branch with the classical PRV strains.The above results indicate that PRV remains widely prevalent in different regions of Hunan Province,and the variant strain is the dominant epi-demic subtype,which provided a scientific basis for exploring the epidemiological characteristics of PRV and the development of vaccines against PR in Hunan Province.