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Objective: Hepatocellular carcinoma (HCC) microenvironment has been recognized as a key contributor for cancer progression, metastasis, and drug resistance. The crosstalk between tumor cells, the vascular endothelial growth factor (VEGF), and the chemokine (C-C motif) ligand 2 (CCL2) signaling networks mediates immunoinhibitory impact and facilitates tumor angiogenesis. The current investigation aimed at exploring the potent anti-cancer activity of the newly designed nano-based anti-cancer therapy comprising anti-VEGF drug, avastin (AV), and CCR2 antagonist (CR) to counteract HCC and tracking its mode of action in vivo. Methods: The prepared AV, CR, and AVCR nanoprototypes were characterized by nanoscale characterization techniques in our previous work. Here, they are applied for unearthing their anti-cancer properties / mechanisms in hepatic cancer-induced rats via analyzing protein levels and genetic expression of the elements incorporated in the angiogenesis, apoptosis, and metastasis signalling pathways. Results: The present results revealed a significant down-regulation in the angiogenesis, survival and metastasis indices along with up-regulation in the pro-apoptotic mediators upon treatment of hepatic cancer-bearing rats with the novel synthesized nanomaterials when compared with the untreated counterparts. We showed across HCC model that anti-VEGF in combination with CCR2 antagonism therapy leads to sensitization and enhanced tumor response over anti-VEGF or CCR2 antagonism monotherapy, particularly in its nanoscale formulation. Conclusion: The present approach provides new mechanistic insights into the powerful anti-hepatic cancer advantage of the novel nanoprototypes which is correlated with modulating critical signal transduction pathways implicated in tumor microenviroment such as angiogenesis, apoptosis and metastasis. This research work presents a substantial foundation for future studies focused on prohibiting cancer progression and recovery by targeting tumor microenviroment.  相似文献   
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目的 观察治伤巴布剂对急性软组织损伤(acute soft tissue injury, ASTI)模型p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)、丝/苏氨酸蛋白激酶(AKT)信号通路的影响,探讨治伤巴布剂干预ASTI的可能作用机制。方法 将40只雄性SD大鼠按照随机数字表法分为正常对照组、模型对照组、治伤巴布剂组、p38MAPK信号通路抑制剂组、AKT信号通路抑制剂组,每组8只。除正常对照组外,其余四组均予以左侧后肢小腿ASTI造模。造模成功后,治伤巴布剂组于标记部位立即予治伤巴布剂(修剪成1.5x3cm大小)外敷,并用胶布固定;其余四组均予等剂量赋形剂(修剪成1.5×3 cm大小)外敷处理,胶布固定;持续外敷,共持续24 h。p38MAPK信号通路抑制剂组在造模前30 min予腹腔注射p38MAPK信号通路抑制剂SB203580(400 μg/kg/天)1次;AKT信号通路抑制剂组在造模前30 min予腹腔注射AKT信号通路抑制剂perifosine(20 mg/kg/天)1次。分别于0(造模前)、2h、4h、8h、12h、24h测量受伤小腿肌肉处的周长,并计算肌肉肿胀率(muscle swelling rate,MSR)。24 h药物干预结束后,采用颈椎脱臼法处死大鼠。后将左侧后肢小腿损伤中心部位进行取材,分成三份。一部分用于观察组织病理学形态变化;一部分用于逆转录聚合酶链反应(RT-PCR)检测核因子-κB(nuclear factor kappa-B,NF-κB)p65 mRNA、肿瘤坏死因子-α(TNF-α)mRNA、白细胞介素-1β(IL-1β)mRNA表达水平;剩下部分用酶联免疫吸附试验(ELISA)法检测骨骼肌组织TNF-α、IL-1β含量水平及蛋白质免疫印迹(Western-blot)法测定p38MAPK、AKT、NF-κB p65、核因子抑制蛋白α(inhibitor kappa B alpha, IκBα)表达水平。结果 与正常对照组相比,模型对照组MSR显著增加(P<0.01);病理形态学上,骨骼肌组织可见大面积肌细胞排列紊乱,肌细胞变性坏死,间质内可见红细胞聚集及大量炎症细胞浸润;骨骼肌组织TNF-α、IL-1β含量水平显著升高(P<0.01);磷酸化p38MAPK(p-p38)/总p38MAPK(t-p38),磷酸化-AKT(p-AKT)/总-AKT(t-AKT)明显升高(P<0.01),NF-κB p65及NF-κB p65mRNA表达水平明显升高(P<0.01)。与模型对照组相比,治伤巴布剂组MSR在治疗第8 h、12 h、24 h显著下降(P<0.01),且在治疗第24 h,其MSR较p38MAPK、AKT信号通路抑制剂组下降更明显(P<0.05);病理学评分显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组下降更显著(P<0.05);骨骼肌组织TNF-α、IL-1β含量水平明显下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组更显著(P<0.05);p-p38/t-p38及p-AKT/t-AKT明显下降(P<0.01),NF-κB p65及NF-κB p65 mRNA表达水平显著下降(P<0.01),且较p38MAPK、AKT信号通路抑制剂组在降低NF-κB p65及NF-κB p65 mRNA相对表达值方面更显著(P<0.01)。结论 治伤巴布剂可能同时对p38MAPK、AKT信号通路产生了一定的抑制作用,引起NF-κB活性下调,NF-κB p65蛋白的表达下调,进而引起骨骼肌组织TNF-α、IL-1β炎性细胞因子含量水平下调,减轻ASTI炎症反应,从而改善ASTI。  相似文献   
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Background

Advanced low-grade ovarian carcinoma (LGOC) is difficult to treat. In several studies, high estrogen receptor (ER) protein expression was observed in patients with LGOC, which suggests that antihormonal therapy (AHT) is a treatment option. However, only a subgroup of patients respond to AHT, and this response cannot be adequately predicted by currently used immunohistochemistry (IHC). A possible explanation is that IHC only takes the ligand, but not the activity, of the whole signal transduction pathway (STP) into account. Therefore, in this study, the authors assessed whether functional STP activity can be an alternative tool to predict response to AHT in LGOC.

Methods

Tumor tissue samples were obtained from patients with primary or recurrent LGOC who subsequently received AHT. Histoscores of ER and progesterone receptor (PR) were determined. In addition, STP activity of the ER STP and of six other STPs known to play a role in ovarian cancer was assessed and compared with the STP activity of healthy postmenopausal fallopian tube epithelium.

Results

Patients who had normal ER STP activity had a progression-free survival (PFS) of 16.1 months. This was significantly shorter in patients who had low and very high ER STP activity, with a median PFS of 6.0 and 2.1 months, respectively (p < .001). Unlike ER histoscores, PR histoscores were strongly correlated to the ER STP activity and thus to PFS.

Conclusions

Aberrant low and very high functional ER STP activity and low PR histoscores in patients with LGOC indicate decreased response to AHT. ER IHC is not representative of functional ER STP activity and is not related to PFS.  相似文献   
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Background

Septic shock is often treated with aggressive fluid resuscitation leading to profound fluid overload. The assessment of fluid status relies on suboptimal measures making treatment difficult. Bioelectrical impedance analysis is an alternative but the validity is unclear. The aim of this study was to determine the validity of bioelectrical impedance analysis for fluid measures in patients with septic shock.

Methods

Single-center, prospective observational cohort study. We included adult ICU patients with septic shock. We evaluated the agreement between measures on the left and right side of the patient and measures 1 h apart by two bioelectrical impedance devices. Results are presented as Bland Altman plots with 95% Limits of Agreements (LoA) and as correlations between bioelectrical impedance analysis results and clinical markers of fluids.

Results

Forty-nine patients were included. The agreement between measures on the left and the right side of the patient and after 1 h was overall without bias, but with wide LoA's. Fluid overload 1 h apart showed the most narrow 95% LoA (−2.4–2.9 L). The same wide limits of agreements were observed when comparing devices. For example, total body water with 95% LoA of −14.8 –16.7 L. Correlations between bioelectrical impedance analysis and clinical measures were low but statistically significant.

Conclusions

In patients with septic shock bioelectrical impedance analysis had no systematic errors or bias, but wide limits of agreement, indicating that the devices have a large and uncorrectable random error. Fluid status by bioelectrical impedance analysis is not sufficiently accurate to guide treatment in this group of patients.  相似文献   
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Peng  L. Q.  Wu  X. X.  Chen  G.  Cai  H. Z.  Tang  Y. P.  Chen  Q. Y.  Chen  X. Y. 《Bulletin of experimental biology and medicine》2022,173(3):335-340
Bulletin of Experimental Biology and Medicine - This study aimed to explore the effects of Wenyang Zhenshuai granules (WZG) on the morphology of cardiomyocytes, cell viability, and the expression...  相似文献   
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