Objective To explore the expression of Ki 67 in 72 cases of breast cancer and to analyze the correlation of Ki67 expression with clinicopathological factors and efficacy of neo-adjuvant chemotherapy .To as-sess the prediction value of Ki 67 in selecting neo-adjuvant chemotherapy .Methods Ki67 expression in tumor tissues of 72 cases of breast cancer was detected before and after neo-adjuvant chemotherapy .Tumor tissues are a-chieved by core needle biopsy .Results Ki67 overexpression was found in those with axillary lymph node ( ALN) metastasis, in pathological stage III and tumor diameter >2 cm(P＜0.05).Ki67 expression was not significantly associated with age(P>0.05).Objective response(OR)rate of neo-adjuvant chemotherapy was 84.2%(61/72). Patients with Ki67 over-expression were more sensitive than those with lower-expression(P>0.05).Positive ex-pression rate of Ki67 was reduced significantly by neo-adjuvant chemotherapy(P＜0.05).Positive expression rate of Ki67 was reduced significantly in pathological complete response ( PCR ) group, clinical complete remission (CCR)group and partial response(PR)group.Conclusion The expression of Ki67 may be a potential predictive biomarker for neo-adjuvant therapy response in patients of breast cancer and can provide the basis for individual therapy for breast cancer .

Development of controllable hypermutable cells can greatly benefit understanding and harnessing microbial evolution. However, there have not been any similar systems developed for Clostridium, an important bacterial genus. Here we report a novel two-step strategy for developing controllable hypermutable cells of Clostridium acetobutylicum, an important and representative industrial strain. Firstly, the mutS/L operon essential for methyldirected mismatch repair (MMR) activity was inactivated from the genome of C. acetobutylicum to generate hypermutable cells with over 250-fold increased mutation rates. Secondly, a proofreading control system carrying an inducibly expressed mutS/L operon was constructed. The hypermutable cells and the proofreading control system were integrated to form a controllable hypermutable system SMBMutC, of which the mutation rates can be regulated by the concentration of anhydrotetracycline (aTc). Duplication of the miniPthl-tetR module of the proofreading control system further significantly expanded the regulatory space of the mutation rates, demonstrating hypermutable Clostridium cells with controllable mutation rates are generated. The developed C. acetobutylicum strain SMBMutC2 showed higher survival capacities than the control strain facing butanol-stress, indicating greatly increased evolvability and adaptability of the controllable hypermutable cells under environmental challenges.
Butanols ; pharmacology ; Cell Engineering ; methods ; Clostridium acetobutylicum ; cytology ; drug effects ; genetics ; physiology ; DNA Methylation ; genetics ; DNA Mismatch Repair ; genetics ; Evolution, Molecular ; Genome, Bacterial ; genetics ; MutS DNA Mismatch-Binding Protein ; genetics ; Mutation ; Operon ; genetics ; Stress, Physiological ; drug effects ; genetics

Direct secretory expression of active microbial transglutaminase (MTG) using heterologous hosts is a promising strategy, although its production level still needs to be improved for industrial production. Pichia pastoris is one of the most efficient expression systems developed in recent years. In this study, secretory expression of active MTG was successfully achieved by co-expressing the pro sequence and mature MTG genes in P. pastoris. Furthermore, we optimized the copy number of pro/MTG expression cassettes and the fermentation conditions. MTG production level reached 7.3 U/mL in 1-liter fermentor through high density fermentation, providing the feasiblity for industrial scale preparation of MTG.
Fermentation ; Genetic Vectors ; genetics ; Pichia ; enzymology ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; Streptomyces ; enzymology ; Transglutaminases ; biosynthesis ; genetics

ObjectiveTo optimize the processing technology of honey bran-fried Rosae Laevigatae Fructus（h-RLF）， formulate relevant quality standards， and explore its improving effect and mechanism on mice with ulcerative colitis（UC） induced by dextran sodium sulfate（DSS）. MethodsTaking the content of polysaccharides and water-soluble extract as the indexes， L₉（3⁴） orthogonal test was used to optimize parameters of the amount of honey bran， frying time and frying temperature. The quality of 15 batches of h-RLF decoction pieces was evaluated according to the optimized process， and the inspection limit standard was preliminarily drawn up. Eighty SPF male Kunming mice were randomly divided into 8 groups， including the blank group， model group， mesalazine group（0.13 g·kg^-1）， RLF group（3.77 g·kg^-1）， bran-fried RLF group（3.77 g·kg^-1）， h-RLF low， medium and high dose groups（1.89， 3.77， 7.54 g·kg^-1）， with 10 mice in each group. The mice in the blank group were free to drink pure water， and the other groups were free to drink 3% DSS solution for 7 days to prepare UC mouse model. Each treatment group was given corresponding drugs by intragastric administration， and the blank and model groups were given equal volume of normal saline. The body weight of mice was recorded daily and the disease activity index（DAI） was calculated. After the administration， the colon tissues of mice were collected to observe the pathological changes by hematoxylin-eosin（HE） staining. The levels of tumor necrosis factor（TNF）-α， interleukin（IL）-1β， IL-6 and IL-10 in the colon of mice were detected by enzyme-linked immunosorbent assay（ELISA）. Western blot was used to detect the expression levels of phosphorylation nuclear transcription factor-κB p65（p-NF-κB p65）， Toll-like receptor 4（TLR4）， p-p38 mitogen-activated protein kinase（p-p38 MAPK）， p-extracellular signal-regulated kinase（p-ERK） and p-c-Jun N-terminal kinase（p-JNK） proteins in colon tissues. ResultsThe optimum processing technology of h-RLF was 20 g honey bran per 100 g RLF， and stir-frying at 200 ℃ for 8 min. The limit standard under the examination of h-RLF was preliminarily formulated as follows：the polysaccharide content should not be less than 25% based on anhydrous glucose（C₆H₁₂O₆）， the content of water-soluble extract should not be less than 38%， the moisture content should not be more than 12.0%， the total ash content should not be more than 5.0%， and the acid-insoluble ash content should not be more than 1.0%. The cluster heat map analysis showed that the quality of RLF from Huanggang， Hubei province was better. Animal experiments showed that compared with the blank group， the DAI score of the model group was significantly increased， the levels of TNF-α， IL-1β and IL-6 in the colon tissue were significantly increased， the IL-10 level was significantly decreased， the colonic mucosa was seriously damaged， accompanied by a large number of inflammatory cell infiltration， tissue congestion and a significant reduction in glands， and the expression levels of p-NF-κB p65， TLR4， p-p38 MAPK， p-ERK and p-JNK proteins were significantly increased（P<0.01）. Compared with the model group， each administration group could alleviate the symptoms of colonic ulcer， the structure of colonic crypt was basically intact， and the glands were arranged in an orderly manner. Among them， the high-dose group of h-RLF had a better effect， which could significantly reduce the DAI score and the levels of TNF-α， IL-1β and IL-6 in colon tissue（P<0.01）， and significantly increase the level of IL-10（P<0.01）， alleviate the colonic mucosal injury， and effectively inhibit the expression levels of p-NF-κB p65， TLR4， p-p38 MAPK， p-ERK and p-JNK proteins（P<0.01）. ConclusionThe key parameters of the processing technology of h-RLF are determined， and the optimized technology is stable and feasible. The established quality standard is simple and reliable， and can be used for the quality control. h-RLF can effectively alleviate DSS-induced UC， and its mechanism may be related to inhibiting the activation of NF-κB/TLR4/MAPK pathway.