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991.
PM2.5 travels along the respiratory tract and enters systemic blood circulation. Studies have shown that PM2.5 increases the incidence of various diseases not only in adults but also in newborn infants. It causes chronic inflammation in pregnant women and retards fetal development. In this study, pregnant rats were exposed to PM2.5 for extended periods of time and it was found that PM2.5 exposure increased immune cells in mother rats. In addition, cytokines and free radicals rapidly accumulated in the amniotic fluid and indirectly affected the fetuses. The authors collected cerebral cortex and hippocampus samples at E18 and analyzed changes of miRNA levels. Expression levels of cortical miR‐6315, miR‐3588, and miR‐466b‐5p were upregulated, and positively correlated with the genes Pkn2 (astrocyte migration), Gorab (neuritogenesis), and Mobp (allergic encephalomyelitis). In contrast, PM2.5 decreased expression of miR‐338‐5p and let‐7e‐5p, both related to mental development. Further, PM2.5 exposure increased miR‐3560 and let‐7b‐5p in the hippocampus, two proteins that regulate genes Oxct1 and Lin28b that control ketogenesis and glycosylation, and neural cell differentiation, respectively. miR‐99b‐5p, miR‐92b‐5p, and miR‐99a‐5p were decreased, leading to reduced expression of Kbtbd8 and Adam11 which reduced cell mitosis, migration, and differentiation, and inhibited learning abilities and motor coordination of the fetus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1412–1425, 2017.  相似文献   
992.
Di(ethylhexyl)phthalate (DEHP), the most widely used plasticizer, was investigated to determine whether an oxidative stress process was one of the underlying mechanisms for its testicular toxicity potential. To evaluate the effects of selenium (Se), status on the toxicity of DEHP was further objective of this study, as Se is known to play a critical role in testis and in the modulation of intracellular redox equilibrium. Se deficiency was produced in 3‐weeks‐old Sprague–Dawley rats feeding them ≤0.05 mg Se /kg diet for 5 weeks, and Se‐supplementation group was on 1 mg Se/kg diet. DEHP‐treated groups received 1000 mg/kg dose by gavage during the last 10 days of the feeding period. Activities of antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), glutathione peroxidase 4 (GPx4), thioredoxin reductase (TrxR)], catalase (CAT), superoxide dismutase (SOD), and glutathione S‐transferase (GST); concentrations of reduced glutathione (GSH), oxidized glutathione (GSSG), and thus the GSH/GSSG redox ratio; and thiobarbituric acid reactive substance (TBARS) levels were measured. DEHP was found to induce oxidative stress in rat testis, as evidenced by significant decrease in GSH/GSSG redox ratio (>10‐fold) and marked increase in TBARS levels, and its effects were more pronounced in Se‐deficient rats with ~18.5‐fold decrease in GSH/GSSG redox ratio and a significant decrease in GPx4 activity, whereas Se supplementation was protective by providing substantial elevation of redox ratio and reducing the lipid peroxidation. These findings emphasized the critical role of Se as an effective redox regulator and the importance of Se status in protecting testicular tissue from the oxidant stressor activity of DEHP. © 2011 Wiley Periodicals, Inc. Environ Toxicol 29: 98–107, 2014.  相似文献   
993.
The fungicide, methoxyethylmercury chloride, was given in a saline solution to four groups of Sprague-Dawley C D rats (5 , 5 ) as a single injection (IP) of 0, 0.5, 1.0, and 2.0 mg Hg/kg. In a three-day period, no changes were observed in urine collected every 24 h from rats given 0 or 0.5 mg Hg/kg; 1 mg Hg/kg induced only a transient increase of urine gamma glutamyl transferase (x 4) and alkaline phosphatase (x 2.5) on the day 2; 2.0 mg Hg/kg caused an early increase of enzymuria (day 1 and day 2) and a decrease of Na+, Cl, K+, urea, and creatinin excretion. Urine enzymes and total mercury excretion were higher in males. These time-related variations of enzymuria, compared to previous results with Hg Cl2, could reflect the existence of metabolites more toxic than the native compound.  相似文献   
994.
Context Opioids have been used as the reference treatment on chronic pain. However, they are related to serious adverse effects which affect the patient compliance to treatment, as well as, his quality of life. Particulate formulations have been investigated as an alternative to improve opioid efficacy and safety. Objective Summarise the available studies concerning micro and nanoencapsulated opioid formulations discussing their biopharmaceutical characteristics, such as composition, size, in vitro release, pharmacokinetic and antinociceptive profile. Methods Papers available in 1995–2015 at Medline, Science Direct and Web of Science databases were collected and assessed. Searches were performed using varied combinations of the keywords of this work. Results Opioid-loaded particles showed prolonged drug release with maintenance of serum therapeutic concentrations and extended analgesia when compared with the free drugs. The side effects incidences were reduced or maintained the same. Conclusion Particulate formulations can significantly increase both potency and safety profiles of opioids.  相似文献   
995.
Preclinical Research
Sonodynamic therapy (SDT) is a cutting edge approach to treating cancer that involves necrosis and/or apoptosis. Multiwalled carbon nanotubes functionalized with carboxylic groups (MWCNTs‐COOH) due their physicochemical structure represent a novel drug delivery system in the field of nanomedicine. The purpose of the research reported in this paper was to increase the antitumor potency and reduce the potential side effects of protohemin (Ph), a sonosensitizer for SDT, which was noncovalently encapsulated into MWCNTs‐COOH (MWCNTs‐Ph). The Ph loading efficiency in MWCNTs‐COOH carrier was determined as approximately 68.8% (w/w). The growth inhibition rate of MWCNTs‐Ph (Ph: 180 μg/mL) was approximately 95 ± 8.5%, whereas Ph‐F (Ph: 180 μg/mL) inhibited 58 ± 4.5% of tumor cell. Ph (Ph: 180 μg/mL) alone had no antitumor effect in HepG‐2 cells using ultrasound treatment at 1.0 MHz and 0.5 W/cm2 for 100 s. Assessment of the antitumor effects of MWCNTs‐Ph and Ph‐F at day 11 after SDT showed that he tumor inhibition ratio for MWCNTs‐Ph (6.18 × 10?2 g·kg?1·d?1) was 82.8%, twice that of Ph‐F (6.18 × 10?2 g·kg?1·d?1) ay 41.8%. In conclusion, MWCNTs‐Ph had increased antitumor efficiency and also decreased potential side effects. Drug Dev Res 77 : 152–158, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
996.
Tetrandrine (TET) has been reported to induce anti‐cancer activity in many human cancer cells and also to inhibit cancer cell migration and invasion. However, there are no reports to show TET inhibits cell migration and invasion in human brain glioblastoma multiforme GBM 8401 cells. In this study, we investigated the anti‐metastasis effects of TET on GBM 8401 cells in vitro. Under sub‐lethal concentrations (from 1, 5 up to 10 μM), TET significantly inhibited cell mobility, migration and invasion of GBM 8401 cells that were assayed by wound healing and Transwell assays. Gelatin zymography assay showed that TET inhibited MMP‐2 activity in GBM 8401 cells. Western blotting results indicated that TET inhibited several key metastasis‐related proteins, such as p‐EGFR(Tyr1068), SOS‐1, GRB2, Ras, p‐AKT(Ser473) and p‐AKT(Thr308), NF‐κB‐p65, Snail, E‐cadherin, N‐cadherin, NF‐κB, MMP‐2 and MMP‐9 that were significant reduction at 24 and 48 hours treatment by TET. TET reduced MAPK signaling associated proteins such as p‐JNK1/2 and p‐c‐Jun in GBM 8401 cells. The electrophoretic mobility shift (EMSA) assay was used to investigate NF‐κB and DNA binding was reduced by TET in a dose‐dependently. Based on these findings, we suggested that TET could be used in anti‐metastasis of human brain glioblastoma multiforme GBM 8401 cells in the future.  相似文献   
997.
Triptolide, a traditional Chinese medicine, obtained from Tripterygium wilfordii Hook F, has anti‐inflammatory, antiproliferative, and proapoptotic properties. We investigated the potential efficacy of triptolide on murine leukemia by measuring the triptolide‐induced cytotoxicity in murine leukemia WEHI‐3 cells in vitro. Results indicated that triptolide induced cell morphological changes and induced cytotoxic effects through G0/G1 phase arrest, induction of apoptosis. Flow cytometric assays showed that triptolide increased the production of reactive oxygen species, Ca2+ release and mitochondrial membrane potential (ΔΨm), and activations of caspase‐8, ‐9, and ‐3. Triptolide increased protein levels of Fas, Fas‐L, Bax, cytochrome c, caspase‐9, Endo G, Apaf‐1, PARP, caspase‐3 but reduced levels of AIF, ATF6α, ATF6β, and GRP78 in WEHI‐3 cells. Triptolide stimulated autophagy based on an increase in acidic vacuoles, monodansylcadaverine staining for LC‐3 expression and increased protein levels of ATG 5, ATG 7, and ATG 12. The in vitro data suggest that the cytotoxic effects of triptolide may involve cross‐talk between cross‐interaction of apoptosis and autophagy. Normal BALB/c mice were i.p. injected with WEHI‐3 cells to generate leukemia and were oral treatment with triptolide at 0, 0.02, and 0.2 mg/kg for 3 weeks then animals were weighted and blood, liver, spleen samples were collected. Results indicated that triptolide did not significantly affect the weights of animal body, spleen and liver of leukemia mice, however, triptolide significant increased the cell populations of T cells (CD3), B cells (CD19), monocytes (CD11b), and macrophage (Mac‐3). Furthermore, triptolide increased the phagocytosis of macrophage from peripheral blood mononuclear cells (PBMC) but not effects from peritoneum. Triptolide promoted T and B cell proliferation at 0.02 and 0.2 mg/kg treatment when cells were pretreated with Con A and LPS stimulation, respectively; however, triptolide did not significant affect NK cell activities in vivo. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 550–568, 2017.  相似文献   
998.
In this study, a type 1 RIP, designated as Jc‐SCRIP, was first isolated from the seed coat of Jatropha curcas Linn. It was purified by ammonium sulfate precipitation and chromatography on DEAE‐Sephacel? and CM‐cellulose columns. Purification fold of Jc‐SCRIP increased 113.8 times, and the yield was 1.13% of the total protein in the final step. It was shown to be a monomeric glycoprotein with a molecular mass of 38 938 Da, as determined by MALDI‐TOF/MS. It exhibited hemagglutination activity and possessed strong N‐glycosidase activity. The antimicrobial activity of Jc‐SCRIP was tested against nine human pathogenic bacteria and one fungus; the most potent inhibitory activity was against Staphylococcus epidermidis ATCC 12228, with minimum inhibitory concentration value of 0.20 μm . Jc‐SCRIP demonstrated in vitro cytotoxicity against human breast adenocarcinoma cell line (MCF‐7), a colon adenocarcinoma (SW620), and a liver carcinoma cell line (HepG2), with IC50 values of 0.15, 0.25, and 0.40 mm , respectively. The results suggested that Jc‐SCRIP may be a potential natural antimicrobial and anticancer agent in medical applications.  相似文献   
999.
We report the extracranial venous ultrasound findings in a case of pseudotumor cerebri (PTC) following unilateral radical neck dissection (rND). PTC is known to be a rare complication following bilateral rND, and is caused by venous outflow obstruction. Single cases of PTC have been reported after unilateral rND, and are thought to be due to resection of the dominant internal jugular vein (IJV) in the presence of a hypoplastic or aplastic contralateral transverse sinus. Our patient developed PTC despite prominent flow in the contralateral IJV as shown by venous ultrasound. No compensatory increase in flow in the vertebral veins was observed, as confirmed by digital subtraction angiography. We conclude that the physiological collateral function of the vertebral venous system and deep neck veins was insufficient and contributed to global venous outflow obstruction in our case of unilateral rND.  相似文献   
1000.
目的:报道经玻璃体腔内注射高剂量曲安奈德(triamcinolone acetonide,TA)联合光动力学疗法(photodynamic therapy,PDT)治疗老年性黄斑变性( age related macular degeneration, AMD)的脉络膜新生血管(choroidal neovascularization,CNV)后发生的脉络膜毛细血管萎缩。方法:我们采用非随机回顾性干涉治疗病例。在阿利坎特学院眼科,连续观察51眼(实验组)玻璃体腔内的注射(19.4±2.1)mg/0.1mL TA联合PDT治疗AMD的全部中心凹下型CNV患者,经过2a的随访,检查黄斑部脉络膜毛细血管和视网膜色素上皮细胞(RPE)萎缩情况。同时,采用单独PDT治疗的连续30眼患者作为对照组,其年龄,性别和AMD的CNV类型及大小与实验组相匹配。结果:随访24mo后,在治疗区域21/47眼(45%,实验组)和7/30眼(23%,对照组)发展成黄斑部RPE和脉络膜毛细血管萎缩(P=0.04,卡方检验)。实验组平均最大萎缩区域的直径为(5044±1666)μm,而对照组为(4345±1550)μm。在实验组中,RPE萎缩患者的平均最佳矫正视力为(0.87±0.33),而非RPE萎缩患者的平均最佳矫正视力为(0.66±0.26) (P=0.11,秩和U检验)。结论:玻璃体腔内注射大剂量TA联合PDT治疗可能会增加RPE和脉络膜毛细血管萎缩的风险。  相似文献   
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