早期大剂量维生素C对重症急性胰腺炎大鼠核因子-κB的影响

目的:观察早期大剂量应用抗坏血酸(维生素C)对重症急性胰腺炎(SAP)大鼠的核因子-!B(NF-!B)的影响,研究其作用机制。方法:将72只SAP模型SD大鼠随机分成3组,每组各24只。A组:由大鼠股静脉滴注生理盐水5 ml/kg。B组:大鼠股静脉滴注Vit C 15 mg/kg加生理盐水至5 ml/kg。C组:由大鼠股静脉滴注Vit C 150 mg/kg加生理盐水至5 ml/kg。另取8只SD大鼠作为正常对照组。各组分别于8 h和24 h处死8只大鼠,采血测淀粉酶、脂肪酶、维生素C(PV-C)、超氧化物歧化酶(SOD)、TNF-αI、L-6。大鼠处死时分别取胰头组织3份,一份组织HE染色,行光镜检查,按Kusske的方法,对水肿、炎症、出血和坏死分别评分;一份制成超薄切片,行电镜检查;另一份SP法进行免疫组化染色,检测NF-!B的表达。每组另外8只大鼠观察3 d内存活情况,计算3 d成活率。结果:各组大鼠3 d内的生存率为正常对照组100%(8/8),A组0%(0/8),B组12.5%(1/8),C组50%(4/8),C组的3 d生存率显著高于其他两组(P<0.05)。各组的4项病理学评分均高于正常对照组(P<0.01),C组的4项病理学评分均低于A、B组(P<0.05)。透射电镜检查示C组中分泌颗粒较少,其包膜完整、内质网轻度肿胀、线粒体清晰,未见大片坏死。SAP大鼠体内淀粉酶、脂肪酶、细胞因子TNF-α和IL-6的水平明显增高,血清SOD和P-VC降低,胰腺组织中NF-!B活化阳性胰腺细胞数明显增多。C组的血清淀粉酶和脂肪酶低于A、B组(P<0.05),SOD和P-VC水平高于A、B组(P<0.05),血清TNF-αI、L-6水平低于A、B组(P<0.05),胰腺组织NF-!B活化水平低于A、B组(P<0.05)。结论:早期大剂量应用Vit C有助于及时提高SAP大鼠的P-VC、E-SOD水平,降低体内淀粉酶、脂肪酶、TNF-αI、L-6水平,其作用机制可能与大剂量Vit C抑制SAP大鼠体内NF-!B活化、在整体水平上抑制细胞因子基因表达、有助于机体免受自由基和过量细胞因子的损伤及减轻胰腺组织的病理性改变等因素有关。     

大鼠肝细胞Ⅰ，Ⅲ型前胶原基因表达及PDGF的影响

目的观察大鼠肝细胞Ⅰ，Ⅲ型前胶原基因的表达及ＰＤＧＦ对其表达的影响．方法应用原位杂交技术检测分离培养的ＳＤ大鼠肝细胞（ｎ＝３０）内Ⅰ，Ⅲ型前胶原基因的表达．同时观察１０μｇ／Ｌ（ｎ＝３０）和３０μｇ／Ｌ（ｎ＝３０）ＰＤＧＦ促进前胶原基因表达的作用．测定基因表达颗粒总面积占细胞总面积的百分比，并作比较分析．结果无论正常肝细胞或是在两种浓度的ＰＤＧＦ存在时，肝细胞内均可见到Ⅰ，Ⅲ型前胶原基因的表达．正常肝细胞Ⅰ，Ⅲ型前胶原基因表达面积的百分比（％）为７７±１９和７５±２１；加１０μｇ／ＬＰＤＧＦ后为１１５±１９和１１２±１０，而加３０μｇ／Ｌ后为１５２±３４及１８１±２８，且在后者中表达明显增强（Ｐ＜００５及Ｐ＜００１）．结论ＰＤＧＦ在转录水平上促进肝细胞胶原的合成．     

An enzymatic cow immunity-targeted approach to reducing milk somatic cell count: 3. A comparative field trial

The effectiveness of lysosubtilin and lysozyme, a combination thereof and a combination of these enzyme preparations (each alone and in combination) with vitamins as possible coimmunostimulants, which reduced the milk somatic cell count (SCC), were compared in a field trial. Seventy second to third lactation Lithuanian Black and White cows with a similar milk SCC ([750±200]×10³?cells?ml^?1) and of a similar weight (550±50?kg) were involved in the trial and were randomly allocated into seven groups (n=10). Lysosubtilin and/or lysozyme at doses of 0.02?g?kg?wt^?1 and 0.2?g?kg?wt^?1, respectively, and vitamins A, C and E (if any) at doses twice as high as required for nutritional adequacy were given, except for control group cows, once daily with feed for ten successive days. After four-, seven-, and ten-day periods of giving enzymes (with or without vitamins) a significant reduction of SCC (p<0.001) was observed in the milk of cows that received a combination of lysozyme with vitamins. On the tenth day a significant reduction of SCC (p<0.001) was also observed in the milk of cows that received lysozyme and lysosubtilin (each alone; without vitamins) or lysosubtilin in combination with vitamins. At the end of the trial (on the 15th day) SCC in milk of cows of all of the study groups was significantly lower (p<0.001) when compared with that of the control group.     

RNAi下调survivin表达诱导成人神经细胞瘤细胞凋亡

目的利用RNA干扰技术下调凋亡抑制因子survivin在人成神经细胞瘤细胞系SH-SY5Y中的表达,并评价其对肿瘤细胞凋亡的影响。方法将设计合成的寡核苷酸片段退火后连入pBSHH1构建survivin的短发夹RNA表达质粒pBSHH1-survivin;通过RT-PCR和Western印迹评价其对SH-SY5Y细胞内源性survivin表达的抑制作用;运用Hoechst33258核染色、DNA凝胶电泳以及AnnexinFITC染色检测survivin表达下调对SH-SY5Y细胞凋亡的影响。结果酶切和DNA测序证实survivin的短发夹RNA表达质粒构建成功;RT-PCR和Western印迹表明质粒转染SH-SY5Y细胞后能明显下调survivin的表达;Hoechst33258核染色、DNA凝胶电泳以及AnnexinⅤFITC染色显示下调survivin的表达能诱导SH-SY5Y细胞凋亡。结论成功构建了有效针对survivin的短发夹RNA表达质粒;下调survivin的表达能诱导SH-SY5Y细胞凋亡。     

Effect of postbariatric maternal weight loss and surgery to conception interval on perinatal outcomes of nulliparous women

BackgroundBariatric surgery is associated with an increased risk of delivering a small neonate. The role of maternal weight loss and surgery to conception interval is unclear.ObjectivesTo investigate the effect of maternal weight loss, as a result of bariatric surgery, and surgery to conception interval on fetal growth and birthweight (BW).SettingInner London Teaching HospitalMethodsWe studied prospectively nulliparous women with previous bariatric surgery. Information on type, time, and presurgery weight was obtained. Surgery-to-conception interval was calculated as the time between surgery and conception, defined as the fourteenth day of the pregnancy dated by first trimester ultrasound scan. In the first trimester, maternal weight was measured. Assessment of maternal weight change between presurgery and first trimester of pregnancy was defined as total weight loss (TWL) (%). Fetal ultrasound scans were performed twice; 30–32 and 35–37 weeks’ gestation and estimated fetal weight (EFW) was calculated. Fetal growth rate was calculated as the ratio of EFW increase (in grams) between 30–32 and 35–37 weeks divided by the time interval (in days) between the 2 examinations. BW was recorded.ResultsThe study included 54 pregnant women, 26 with a restrictive procedure (gastric band or vertical sleeve gastrectomy) and 28 with a gastric bypass. Surgery to conception interval was not a significant predictor of the offspring’s growth. Maternal TWL was a significant predictor of fetal growth rate (P = .04) and predictor of BW (P = .005), even after adjustment for confounders.ConclusionsMaternal weight loss, as a result of bariatric surgery, has an inverse correlation with fetal growth rate and BW.     

The influence of bariatric surgery on hip and knee joint pain: a systematic review

Obesity increases the risk of osteoarthritis and the chance of needing joint replacement arthroplasty to reduce lower limb joint pain. Although nonsurgical weight loss interventions can reduce hip and knee joint pain, bariatric surgery may be a more feasible treatment option for people with severe obesity. However, it is unclear whether weight loss through bariatric surgery can positively influence hip and knee joint pain. Our objective was to evaluate the influence of bariatric surgery on hip and knee joint pain in people with obesity by conducting a systematic review of the literature. The PubMed, EMBASE, and Cochrane bibliographic databases were searched for studies published between 1947 and September 2019. Risk of bias of the identified studies was independently assessed by 2 reviewers using JBI’s Critical Appraisal Checklist for Case Series and the Newcastle-Ottawa Scale. This review included 23 studies, all of which evaluated knee pain and 9 of which also evaluated hip pain. Reported results regarding hip pain intensity and the proportion of participants with hip pain were too limited to draw useful conclusions. Reported results regarding knee pain suggest that weight loss after bariatric surgery reduced knee pain intensity, as well as the proportion of participants with knee pain. The overall risk of bias of the majority of included studies (83%; n = 19) was judged to be unclear to high. Four small studies were judged as having a low risk of bias. Results of this systematic review suggest that bariatric surgery can positively influence hip and knee joint pain, but conclusive evidence is lacking because most of the included studies were judged as having plausible bias overall and in their key domains. Well-designed randomized controlled trials evaluating the influence of bariatric surgery on hip and knee joint pain using standardized joint pain measures are needed.