To obtain recombinant human β2-microglobulin (rhβ2M) with properties of good solubility and high purity from E. coli, prokaryotic expression conditions were optimized and protein purification was performed in this study. After testing the effect of different IPTG concentrations, temperatures and induction times on the production of rhβ2M, the optimum expression conditions were determined, i. e. joining IPTG to final concentration being 0.8 mmol/L and inducing time 6 h and at temperature of 25 degrees C. Under the optimum induction conditions, the ratio of soluble rhβ2M to soluble bacterial protein was 63.7%. After purified by Ni Sepharose 6 Fast Flow, the purity of rhβ2M achieved a greater value of 95%. Western blot analysis revealed that rhβ2M possessed the antigen property that specifically interacted with anti-β2M antibody.
Blotting, Western ; Escherichia coli ; metabolism ; Humans ; Recombinant Proteins ; biosynthesis ; Solubility ; beta 2-Microglobulin ; biosynthesis

Objective:To investigate the expression and clinical significance of long non-coding RNA (LncRNA) CRNDE in cer-vical cancer. Methods:Specimens of cervical cancer tissues and matched non-tumor para-neoplastic tissues were collected from 87 pa-tients who underwent surgery in the Kaiping Central Hospital, China. Quantitative real-time PCR was used to examine the expression of LncRNA CRNDE, and its correlation with clinicopathological features was analyzed. Results:LncRNA CRNDE expression was sig-nificantly up-regulated in cervical cancer tissues than in adjacent non-tumor tissues (P<0.05). Increased LncRNA CRNDE expression was significantly correlated with FIGO stage, lymph node metastasis, and depth of cervical invasion (P<0.05). Moreover, a higher ex-pression of LncRNA CRNDE demonstrated significantly poorer overall survival in cervical cancer patients than in those with lower Ln-cRNA CRNDE expression (P<0.05). Multivariate analyses suggested that LncRNA CRNDE expression served as an independent pre-dictor for overall survival. Conclusion:Our findings posit that LncRNA CRNDE may be a potential prognostic marker and therapeutic target for cervical cancer.

Objective To investigate the anti-inflammatory effect of penehyclidine hydrochloride on oleic acid-induced acute respiratory distress syndrome (ARDS) in rats.Methods According to randomize number table method, 30 adult male Sprague-Dawley (SD) rats were divided into control group, model group and treatment group. Catheters were placed in femoral vein in each group. The control group was injected with 1.1 mL/kg physiological saline; the model group was injected with 0.1 mL/kg oleic acid and then injected with 1.0 mL/kg normal saline to establish ARDS model; the treatment group was injected with 0.1 mL/kg oleic acid and then injected with 1.0 mL/kg penehyclidine hydrochloride. At 3 hours after the model was established, blood gas analysis was carried out in each group, oxygenation index (PaO2/FiO2) was calculated, and the levels of serum interleukins (IL-1, IL-6) were measured by enzyme linked immunosorbent assay (ELISA). Rats were sacrificed to harvest lung tissue, and the lung wet/dry ratio (W/D) was calculated; the morphological changes of lung tissue was observed under microscope; the superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels were detected by colorimetry; the expression of tumor necrosis factor-α(TNF-α) in lung tissue was detected by immunohistochemical method. The correlations between lung W/D ratio and various indicators were analyzed using Pearson correlation test.Results Compared with the control group, PaO2/FiO2 in model group was significantly decreased, lung W/D ratio was significantly increased, serum IL-1, IL-6 levels and lung tissue MDA content were significantly increased, lung tissue SOD activity was significantly decreased; the alveolar space was filled with exudate, neutrophils and red blood cells, and there were obvious edema and broadening in pulmonary interstitial and alveolar under light microscope; the type Ⅱ alveolar epithelial cells were partly destroyed, accompanied by lamellar body degeneration and emptying phenomenon under electron microscope; and immunohistochemistry showed that the positive expression of TNF-α in lung tissue was significantly increased. Compared with the model group, PaO2/FiO2 in the treatment group was significantly improved [mmHg (1 mmHg = 0.133 kPa): 204.42±31.61 vs. 113.91±47.78,P < 0.05], the lung W/D ratio was significantly decreased (5.80±0.44 vs. 6.82±0.59,P < 0.01), serum IL-1, IL-6 levels and lung tissue MDA content were significantly decreased [IL-1 (μg/L): 18.38±0.28 vs. 20.04±0.39, IL-6 (μg/L): 12.64±0.67 vs. 14.28±1.33, MDA (nmol/mg): 3.95±0.28 vs. 5.17±0.29, allP < 0.05], the activity of SOD in lung tissue was significantly increased (U/mg: 48.75±2.41 vs. 45.09±1.69,P < 0.01), histological and pathological changes were significantly reduced, and the positive expression of TNF-α in lung tissue was significantly reduced [positive cell rate: (25.80±3.44)％ vs. (38.82±3.59)％,P < 0.01].Conclusion Penehyclidine hydrochloride can effectively improve the oxygenation, alleviate lung injury and reduce pulmonary edema in oleic acid induced ARDS rat by decreasing lung W/D ratio, inhibiting oxidative stress and inflammatory response.

AIM: To investigate the protective effect and mechanism of Danlou tablet on retinal ischemia-reperfusion injury(RIRI)in mice.METHODS: A total of 40 ApoE-/- mice were fed with high fat diet for 6 wk, and the RIRI model was established by anterior chamber infusion of pressurized saline. The mice were divided into control group(normal saline for 8 wk), RIRI model group(normal saline for 8 wk), and low-, medium-, and high-dose Danlou tablets groups [1, 2, and 4 g/(kg·d), respectively, for 8 wk]. The morphological changes of retina were observed by hematoxylin-eosin(HE)staining, retinal cell apoptosis was detected by terminal-deoxynucleoitidyl transferase mediated Nick-End Labeling(TUNEL)staining. The Western-blot assay was used to detect the expression of retinal tissue sample Kelch-like ech-associated protein 1(Keap1), nuclear factor E2 related factor 2(Nrf2), heme oxygenase 1(HO-1), and superoxide dismutase(Sod2)proteins.RESULTS: Compared with the control group, the mouse retina was atrophic with thinning thickness and increasing cell apoptosis, down-regulation of Sod2 protein expression, and up-regulation of Keap1 protein expression in the RIRI model group(all P<0.01). Compared with the RIRI model group, the retinal thickness increased in the medium- and high-dose of Danlou tablets groups(all P<0.01), and the cell apoptosis of retina decreased in the low-, medium- and high-dose of Danlou tablets groups(all P<0.05). There were no significant differences in the expression of Keap1 and HO-1 proteins of mouse retina tissue in the low-dose of Danlou tablets group(P>0.05). The expression of Sod2, Nrf2 and HO-1 proteins up regulated, and the expression of Keap1 protein down regulated in the medium- and high-dose of Danlou tablets groups(all P<0.05).CONCLUSION: Danlou tablet can alleviate RIRI-induced atrophy and thinning of retina and retinal cell apoptosis by regulating Keap1-Nrf2/HO-1 signal pathway and reducing oxidative stress.

OBJECTIVETo evaluate the short-term outcomes and perioperative safety of proximally extended resection for locally advanced rectal cancer after neoadjuvant chemoradiotherapy.

METHODSFrom colorectal cancer database in The Sixth Affiliated Hospital of Sun Yat-sen University, a cohort of patients who underwent neoadjuvant chemoradiotherapy(1.8-2.0 Gy per day, 25-28 fractions, concurrent fluorouracil-based chemotherapy) followed by curative sphincter-preserving surgery for locally advanced rectal cancer between May 2016 and June 2017 were retrospectively identified. Exclusion criteria were synchronous colon cancer, intraoperatively confirmed distal metastasis, multiple visceral resection, and emergency operation. Thirty-one patients underwent proximal extended resection and two were excluded for incomplete extended resection, then 29 patients were enrolled as the extended group. Using propensity scores matching with 1/1 ration, 29 locally advanced rectal cancer patients who underwent conventional resection after neoadjuvant chemoradiotherapy at the same time were matched as the conventional group. Clinical data of two groups were analyzed, and the baseline characteristics and short-term outcomes were compared using the t test, χtest, or Mann-Whitney U test.

RESULTSTwo groups were well balanced with respect to the baseline characteristics after propensity score matching. As compared with conventional group, patients in extended group had longer surgical specimen [(18.8±5.1) cm vs.(11.6±3.4) cm, t=6.314, P=0.000] and longer proximal resection margin [(14.8±5.5) cm vs.(8.2±3.0) cm, t=5.725, P=0.000], but also had longer total operating time [(322.4±100.7) min vs.(254.6±70.3) min, t=2.975, P=0.004] and more intraoperative blood loss [100(225) ml vs. 100(50) ml, Z=-2.403, P=0.016]. No significant differences were observed in the length of distal resection margin, ratio of positive resection margin, number of retrieved lymph node, time of analgesic use, time of draining tube use, time to first flatus, time to first oral diet, and postoperative hospital stay. During the perioperative period of 30 days, the morbidity of complication in extended group and conventional group was 17.2%(5/29) and 34.5% (10/29), respectively (P=0.134).

CONCLUSIONProximally extended resection is a radical and safe surgical alternative for locally advanced rectal cancer after neoadjuvant chemoradiotherapy, which can potentially reduce the risk of anastomosis complication.