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《Pancreatology》2022,22(7):880-886
BackgroundPremature intracellular trypsinogen activation has long been considered a key initiator of acute pancreatitis (AP). Cathepsin B (CTSB) activates trypsinogen, while cathepsin L (CTSL) inactivates trypsin(ogen), and both proteins play a role in the onset of AP.MethodsAP was induced by 7 hourly intraperitoneal injections of cerulein (50 μg/kg) in wild-type and pancreas-specific conditional Ctsb knockout (CtsbΔpan), Ctsl knockout (CtslΔpan), and Ctsb;Ctsl double-knockout (CtsbΔpan;CtslΔpan) mice. Pancreatic samples were collected and analyzed by histology, immunohistochemistry, real-time PCR, and immunoblots. Trypsin activity was measured in pancreatic homogenates. Peripheral blood was collected, and serum amylase activity was measured.ResultsDouble deletion of Ctsb and Cstl did not affect pancreatic development or mouse growth. After 7 times cerulein injections, double Ctsb and Ctsl deficiency in mouse pancreases increased trypsin activity to the same extent as that in Ctsl-deficient mice, while Ctsb deficiency decreased trypsin activity but did not affect the severity of AP. CtsbΔpan;CtslΔpan mice had comparable serum amylase activity and histopathological changes and displayed similar levels of proinflammatory cytokines, apoptosis, and autophagy activity compared with wild-type, CtsbΔpan, and CtslΔpan mice.ConclusionDouble deletion of Ctsb and Ctsl in the mouse pancreas altered intrapancreatic trypsin activity but did not affect disease severity and inflammatory response after cerulein-induced AP. 相似文献
13.
目的 及时发现武汉市血吸虫病重点水域水体感染性,减少血吸虫病传播风险。 方法 选择血吸虫病易感重点水域长江武汉段、府河-沦河水系、东荆河-通顺河水系和金水河水系,采用哨鼠监测法监测水体血吸虫感染风险。 结果 2017—2019 年共开展哨鼠监测 38 点次,涉及全市 8 个区 21 个行政村。 三年共投放哨鼠 760 只,回收哨鼠 742 只,总回收率为 97. 63%;共解剖哨鼠 742 只,未发现阳性,未检获成虫,哨鼠感染率为 0。 结论 武汉市血吸虫病重点水域的水体感染性较低。 相似文献
14.
目的 研究灌饲牙龈卟啉单胞菌(Porphyromonas gingivalis,P. gingivalis)对C57bl/6小鼠结肠炎症的诱导作用。方法 将P. gingivalis ATCC33277液体增菌后备用。将15只C57bl/6小鼠适应1周后随机均分为3组,高浓度组灌饲1 × 109 CFU P. gingivalis,低浓度组灌饲1 × 108 CFU P. gingivalis,而对照组则灌饲等量无菌BHI培养液。每只小鼠每天灌饲1次,3周后处死小鼠,采集结肠及脾脏组织,行HE染色观察组织学变化,并采用实时荧光定量PCR(qRT-PCR)检测结肠组织中CD3抗原(CD3 antigen,epsilon polypeptide,CD3)、受体型蛋白酪氨酸磷酸酶C(protein tyrosine phosphatase,receptor type C,B220)、黏附G蛋白偶联受体E1(adhesion G protein-coupled receptor E1,F4/80)、转化生长因子-β(transforming growth factor-β,TGF-β)及干扰素-γ(interferon-gamma,IFN-γ)的表达水平。结果 HE染色显示高浓度组小鼠结肠黏膜下结缔组织中淋巴滤泡增多,且高浓度组小鼠脾指数出现增高的趋势,但差异无统计学意义(P > 0.05)。qRT-PCR结果显示,与对照组及低浓度组相比,高浓度组小鼠的结肠组织中B220及TGF-β的表达水平显著增高(P < 0.05),其余指标表达水平差异无统计学意义(P > 0.05)。结论 P. gingivalis可诱导结肠炎症,从而增加牙周病患者对消化系统疾病的易感性,且其可能与牙周病病情的严重程度相关。 相似文献
15.
Nicole Di Lascio Claudia Kusmic Chiara Rossi Anna Solini Francesco Faita 《Ultrasound in medicine & biology》2019,45(4):980-988
Information on the common carotid artery and cerebral microcirculation can be obtained by micro-ultrasound (µUS). The aim of the study described here was to investigate high-fat diet-induced alterations in vascular parameters in ApoE–/– mice. Twenty-two ApoE–/– male mice were examined by µUS and divided into the standard diet (ApoE–/–SD) and high-fat diet (ApoE–/–HF) groups. The µUS examination was repeated after 4 mo (T1). Carotid stiffness, reflection magnitude and reflection index were measured; the amplitudes of the first (W1) and second (W2) local maxima, the local minimum (Wb) and the reflection index (RIWIA?=?Wb/W1) were assessed with wave intensity analysis. At T1, ApoE–/–HF mice had increased carotid stiffness (1.48 [0.36] vs. 1.88 [0.51]) and reflection magnitude (0.89 [0.07] vs. 0.94 [0.07]) values. Longitudinal comparisons highlighted increases in carotid stiffness for ApoE–/–HF mice (from 1.37 [0.25] to 1.88 [0.51] m/s) but not for ApoE–/–SD mice (from 1.40 [0.62] to 1.48 [0.36] m/s). ApoE–/–HF mice exhibited carotid artery stiffening and increased wave reflections. 相似文献
16.
目的:为了研究断藤益母汤(DTYMD)在类风湿关节炎中对丝裂原活化蛋白激酶(MAPK)上游激酶的调控作用,阐明DTYMD抗炎的分子机制。方法:培养成纤维样滑膜细胞,将细胞分为空白组,模型组,DTYMD高、中、低质量浓度组(1 000,800,600 mg·l~(-1)),甲氨蝶呤(MTX)组(20μmol·l~(-1))组,采用蛋白免疫印迹法(Western blot),实时荧光定量聚合酶链式反应(Real-time PCR)对丝分裂原活化蛋白激酶激酶激酶2(MEKK2)的蛋白和mRNA表达进行分析。将42只雄性DBA/1J小鼠随机分为6组,每组7只,分别为正常组,模型组,MTX组(2 mg·kg~(-1)),DTYMD低、中、高剂量组(6. 25,12. 5,25 mg·kg~(-1))。除正常组外,其他5组均采用二次免疫法构建胶原诱导型关节炎(CIA)模型。给药结束后,取小鼠后肢踝关节行苏木素-伊红(HE)染色并进行关节病理评分。结果:与模型组比较,DTYMD以浓度依赖方式抑制成纤维样滑膜细胞活性(P 0. 01);与空白组比较,模型组细胞增殖率升高(P 0. 01)。与模型组比较,DTYMD高、中质量浓度组降低MEKK2蛋白及mRNA的表达(P 0. 05,P 0. 01)。与模型组比较,DTYMD不同剂量组均降低细胞基质金属蛋白酶-1(MMP-1),肿瘤坏死因子-α(TNF-α),白细胞介素-6(IL-6)的表达(P 0. 01);与空白组比较,模型组MMP-1,IL-6,TNF-α表达明显上升(P 0. 05,P 0. 01)。在动物实验中,与模型组比较,DTYMD高、中剂量组可以降低CIA小鼠关节肿胀度(P 0. 05,P 0. 01);与正常组比较,模型组小鼠二次免疫后关节明显肿胀(P 0. 05)。在CIA小鼠踝关节HE染色中,与空白组比较,模型组小鼠病理学评分升高(P 0. 01);与模型组比较,DTYMD高、中剂量小鼠关节病理评分明显下降(P 0. 05,P 0. 01)。结论:DTYMD可能通过下调MEKK2对细胞因子IL-6,TNF-α,MMP-1负性调控,从而缓解类风湿关节炎的炎症反应。 相似文献
17.
目的:探讨电子线对胰岛素生长因子-1家族蛋白表达的影响,为研究辐射对肝脏的早期损伤提供依据。方法:采用电子线照射小鼠,照射剂量为1、2、4 Gy,用Western blot法检测照射后12、48和72 h小鼠肝脏中胰岛素生长因子1受体(IGF-1R)、胰岛素生长因子结合蛋白1(IGFBP1)、胰岛素生长因子结合蛋白4(IGFBP4)和胰岛素生长因子1(IGF-1)蛋白表达水平的改变。结果:照射剂量为1 Gy时,与对照组相比,IGF-1蛋白在照射后48 h时表达增加,IGFBP1、IGFBP4和IGF1R蛋白的表达在照射后12、48和72 h均表达减少。照射剂量为2 Gy时,IGF-1和IGFBP4蛋白在照射后48 h时表达增加,其余时间点表达减少。IGFBP1蛋白在照射后12 h时表达增加,48和72 h时表达减少。IGF1R蛋白在照射后3个时间点均呈现为表达减少。照射剂量4 Gy时,肝脏中IGF-1、IGFBP1和IGFBP4蛋白均表达减少,IGF1R蛋白在照射后12 h时表达增加,48、72 h时均表达减少(均为P < 0.05)。结论:电子线照射后小鼠肝脏中胰岛素生长因子-1家族蛋白多以下调表达为主,与前期基因表达的结果相一致,有可能作为反映放射性工作人员早期肝脏损伤的生物标志物之一。 相似文献
18.
Hiroki Katagiri Luis Filipe Mendes Frank P. Luyten 《Journal of tissue engineering and regenerative medicine》2019,13(5):846-856
Nude mice have been extensively used to investigate the potency of tissue engineering strategies for bone repair. However, the contribution of pro‐inflammatory and proregenerative stimuli of the host for the process of new bone formation and integration remains poorly understood. In this study, ectopic bone formation was investigated in nude (Nu) versus wild‐type (WT) mice. Calcium phosphate (CaP) scaffolds (CopiOs [Zimmer] and Bio‐Oss [Geistlich]) were loaded with different concentrations of rhBMP6 (40, 120, and 240 ng/mm3 rhBMP6) and implanted subcutaneously in Nu (BALB/c and NMR1) and WT (BALB/c and c57BL/6) mice. CaP scaffolds loaded with rhBMP6 did not form bone in WT mice. However, in Nu mice, 40 ng/mm3 rhBMP6 was sufficient to generate relevant volumes of new bone at 6 weeks after implantation. Looking into potential underlying mechanisms, TNF‐α blocking antibodies were injected intraperitoneally but could not restore bone formation. Also, mouse periosteal cells (mPDCs) seeded in CopiOs loaded with rhBMP6 did not significantly improve the outcome. Abrogation of bone formation was associated with dense cellular infiltration, in particular with the presence of CD3+ T‐lymphocytes. To probe a correlation between calcium ions and impaired bone formation in WT mice, type 1 collagen gels were loaded with rhBMP6 and calcium chloride and injected subcutaneously. These gels generated new bone in WT mice despite the increased percentage of CD3+ cells at Day 3 after implantation as compared with control gels. Overall, this study illustrated the negative effect of the inflammatory host response on the bone‐forming capacity of rhBMP6 coated on bioceramic scaffolds. 相似文献
19.
Kishor Devalaraja-Narashimha Karoline Meagher Yifan Luo Cong Huang Theodore Kaplan Anantharaman Muthuswamy Gabor Halasz Sarah Casanova John OBrien Rebecca Peyser Boiarsky John McWhirter Hans Gartner Yu Bai Scott MacDonnell Chien Liu Ying Hu Adrianna Latuszek Yi Wei Srinivasa Prasad Tammy Huang George Yancopoulos Andrew Murphy William Olson Brian Zambrowicz Lynn Macdonald Lori G. Morton 《Journal of the American Society of Nephrology : JASN》2021,32(1):99
20.
The aim of this study was to analyze the 4-carvomenthenol (carvo) oral treatment on the experimental model of the combined allergic rhinitis and asthma syndrome (CARAS). BALB/c mice were OVA-sensitized on day zero and 7th (50 μg/mL OVA in 10 mg/mL Al (OH)3) and OVA-challenged (5 mg/mL, 20 μL/animal) for three weeks. In the last week, the animals were dally challenged with aerosol of OVA and the carvo treatment (12.5, 25 or 50 mg/kg) occurred one hour before each OVA-challenge. Data were analyzed and p < 0.05 was considered significant. Carvo (12.5–50 mg/kg) decreased significantly the eosinophil migration into the nasal (NALF) and bronchoalveolar (BALF) cavities as well as on the nasal and lung tissues of sick animals. The treatment also decreased mucus production on both tissue sections stained with PAS (periodic acid-Schiff satin). In addition, the histological analyzes demonstrated that sick mice presented hyperplasia and hypertrophy of the lung smooth muscle layer followed by increasing of extracellular matrix and carvo (50 mg/kg) inhibited these asthmatic parameters. We analyzed the allergic rhinitis signals as nasal frictions and sneezing and observed that carvo decreased these two signals as well as serum OVA-specific IgE titer, type 2 cytokine synthesis, mainly IL-13, with increasing of IL-10 production. Decreasing of IL-13 production corroborated with decreasing of mucus production and these effects were dependent on p38MAPK/NF-κB(p65) signaling pathway inhibition. Therefore, these data demonstrated that a monoterpene of essential oils presents anti-allergic property on an experimental model of CARAS suggesting a new drug prototype to treat this allergic syndrome. 相似文献