Methylene blue reduces IL-1β levels by enhancing ERK1/2 and AKT phosphorylation to improve diabetic retinopathy in rats / 细胞与分子免疫学杂志

Objective To investigate the neuroprotective effect of methylene blue on diabetic retinopathy in rats. Methods Thirty SD rats were randomly divided into blank, control and experimental groups. The control and experimental groups were induced with diabetes by streptozotocin (STZ) intraperitoneal injection. After 6 weeks of successful modeling, the experimental group received intravitreal injection of methylene blue at a dose of [0.2 mg/(kg.d)], while the control group received an equal amount of dimethyl sulfoxide (DMSO) intravitreal injection, both continuously injected for 7 days. ELISA was used to detect the levels of retinal superoxide dismutase (SOD), 8-iso-prostaglandin F2alpha (iPF2α) and interleukin-1β (IL-1β) in rats. Western blot analysis was used to detect the expression of retinal extracellular signal-regulated kinase 1/2 phosphorylation (p-ERK1/2) and phosphorylated protein kinase B (p-AKT), and PAS staining was used to detect retinal morphological changes. Results Compared with the blank group rats, the retinal SOD activity in the control and experimental group rats was significantly reduced. iPF2α, IL-1β and p-ERK1/2 level increased, while p-AKT level decreased. Compared with the control group, the SOD activity of the experimental group rats increased. iPF2α and IL-1β level went down, while p-ERK1/2 and p-AKT level went up significantly. The overall thickness of the retinal layer and the number of retinal ganglion cells were significantly reduced. Conclusion Methylene blue improves diabetic retinopathy in rats by reducing retinal oxidative stress and enhancing ERK1/2 and AKT phosphorylation.

Gene optimization and efficient expression of Trichoderma reesei Cel5A in Pichia pastoris / 生物工程学报

Deficient activity of endo-1,4-beta-glucanase II (Cel5A) secreted by Trichoderma reesei is one of the challenges involved in effective cellulase saccharification of cellulosic substrates. Therefore, we expressed Cel5A in Pichia pastoris by constructing a recombinant strain. With the gene optimization based on codon bias, and the construction of expression vector pPIC9K-eg2, the optimized gene was electro-transformed into P. pastoris GS115 to form transformants. Then, a high Cel5A activity producing recombinant, namely P. pastoris GS115-EG Ⅱ, was selected on G-418 resistant plates, followed by shake-flask cultivation. Enzyme characterization showed that the recombinant Cel5A reacted optimally at pH 4.5 and 60 ℃, with 50 kDa of molecular weight, preferentially degrading amorphous cellulose. Recombinant Cel5A was not significantly different from the native T. reesei Cel5A. Moreover, a shake-flask fermentation of the recombinant strain was optimized as below: incubation temperature 28 ℃, initial pH 5.0, inoculum volume 2%, methanol addition (per 24 h) 1.5% (V/V), sorbitol addition (per 24 h) 4 g/L and Tween 80 4 g/L. Under above optimized condition, the recombinant produced 24.0 U/mL of the Cel5A after 192 h fermentation. When incubated in a 5 L fermentation, Cel5A enzyme activity reached 270.9 U/mL at 180 h, with 4.16 g/L of the total protein. The study indicates that the recombinant strain P. pastoris GS115-EG Ⅱ is extremely suitable for heterologous expression of T. reesei cellulase Cel5A. And the recombinant Cel5A can be used as an alternative to the native T. reesei Cel5A in development of a commercially relevant enzyme based biorefinery process.

The Intratympanic Inflation by Tympanum Inflatable Balloon for Meniere ’s Disease / 听力学及言语疾病杂志

Objective To evaluate the clinical efficacy of the intratympanic inflation by tympanum inflatable balloon for patients with Meniere’s disease(MD) .Methods A total of 36 confirmed cases (according to the listening stage) of Ⅱ - Ⅲ period of MD patients were randomly divided into two groups :experimental group and control group ,18 cases of matched group ,who were staged before preoperation by hearing ,Ⅱ period (average threshold 25~40 dB HL) 6 cases ,Ⅲ period (41~70 dB HL) 12 cases ,were treated by intratympanic methylprednisolone per‐fusion after putting tympanostomy tube under endotoscope ,then once every 3 days perfusion with a total of three times .There were 18 cases of experimental group staged before preoperation by hearing ,Ⅱ period (average thresh‐old 25~40 dB HL) in 5 cases ,Ⅲ period (41~70 dB HL) 13 cases treated by using tympanum inflatable balloon in the tympanum under endotoscope .Two groups were given conventional improved microcirculation and nutritional therapy .Results In 18 cases of patients in experimental group ,for the 18 to 24 months follow -up after treatment ,6 cases of vertigo were fully controlled (grade A) ,10 cases of vertigo basically controlled (grade B) ,2 cases of vertigo partly controlled (grade C) .Vertigo effective control rate was 88 .89% (16/18) .After 18 to 24 months treatment ,two groups of 36 patients with tinnitus and pure tone average threshold had no obvious change .In 18 ca‐ses of patients in the matched group ,during the 18 to 24 months follow -up after treatment ,3 cases of vertigo were fully controlled (grade A) ,7 cases of vertigo basically controlled (grade B) ,8 cases of vertigo partly controlled (grade C) .Vertigo effective control rate was 55 .56% (10/18) .The experimental vertigo basic control rates were higher than the control group (χ2 = 4 .985 ,P<0 .05) .The activitives in the two groups had improved significantly . No obvious differences were found between two groups .Conclusion With the intratympanic gasing by tympanum in‐flatable balloon for patients of Ⅱ - Ⅲ Menier’s disease ,control rates was high and motile ability were improved , but tinnitus and hearing improvement was not obvious .

Effects of Soy Isoflavone on Serum Glucose and Lipid in Orchiectomized Rats / 环境与健康杂志

Objective To investigate the effects of environmental endocrine disruptors-phytoestrogen soybean isoflavone on serum glucose and lipid in rats with orchiectomy.Methods Fifty-four healthy clean male Wistar rats aged 7 weeks were randomly divided into 6 groups,9 in each group,according to their weight and named as the groups of SHAM,ORCH,L-SI,M-SI,H-SI and EC.The rats were injected intraperitoneally with 1.5% sodium pentobarbital according to 40 mg/kg,and they were either shamoperated or orchiectomized.The rats were fed on high fat diet for 4 weeks.There was 1,3,9 g soybean isoflavone and 0.45 mg estrobene per kilogram high fat diet in L-SI,M-SI,H-SI and EC respectively.At the 2nd and 4th week,serum insulin,fasting blood glucose and lipid (TG,TC,HDL and LDL) were detected.Results The weights of rats with orchiectomy was significantly decreased compared with sham-operated rats,and compared with the EC group,the weights of other groups'rats were significantly higher.The weight was decreased along with the increase of the dose of soy isoflavone.At the end of 4 weeks,SIF significantly decreased serum glucose compared with ORCH,and the insulin level was significantly increased in M-SI and H-SI group.SIF and estrogen could significantly decrease TC,but they did not have obvious effect on LDL.SIF could not improve HDL level in rats with orchiectomy.Even though there was no statistic difference,the TG levels of SIF groups were deceased.Conclusion SIF can decrease serum glucose level via raising insulin level in rats with orchiectomy.SIF can decrease serum TC level significantly and regulate TG level while there is no influence on HDL and LDL.