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1.
Ann Surg Oncol ; 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407178

RESUMO

BACKGROUND: Routine performance of internal mammary sentinel lymph node biopsy (IM-SLNB) remains a subject of debate due to no clinical relevance in breast cancer, because it was performed only in clinically axillary lymph node (ALN)-negative patients. In this study, IM-SLNB was performed in clinically ALN-positive patients, and its impact on nodal staging and therapeutic strategy were subsequently analyzed. METHODS: Clinically ALN-positive patients who underwent IM-SLNB were enrolled in this prospective study. Statistical analysis was performed using Chi square test, Mann-Whitney U and logistic regression models with a significance level of 0.05. RESULTS: Among the 352 recruited patients, the internal mammary sentinel lymph node (IMSLN) visualization rate of patients who received initial surgery and neoadjuvant systemic therapy (NST) was 71.9% (123/171) and 33.1% (60/181), respectively. The 183 patients who underwent IM-SLNB successfully had the average time duration of 7 min and the median IMSLN number of 2. There were 87 positive IMSLNs in all the 347 removed IMSLNs, which were mainly concentrated in the second (50.6%) and third (34.5%) intercostal space. The IMSLN metastasis rate was 39.8% (initial surgery) and 13.3% (NST), respectively. All of the 183 IM-SLNB patients received more accurate nodal staging, 57 of whom had stage elevated, which might have prompted modifications to the therapeutic strategy. CONCLUSIONS: IM-SLNB should be routinely performed in clinically ALN-positive patients, and thus more accurate nodal staging and perfect pathologic complete response definition could be put forward. The identification of IMLN metastases by IM-SLNB might potentially influence therapeutic strategies.

2.
Breast J ; 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332886

RESUMO

This study aimed to explore the optimal time of sentinel lymph node biopsy (SLNB) and neo-adjuvant chemotherapy (NAC) and to assess the feasibility of selective elimination of axillary surgery after NAC in clinically node-negative (cN0) patients. From April 2010 to August 2018, 845 patients undergoing surgery after NAC were included in this retrospective study to analyze the correlation between different clinicopathological characteristics of cN0 patients and negative axillary lymph node after NAC (ypN0). Among the 148 cN0 patients, 83.1% (123/148) were ypN0. The rates of ypN0 in patients with hormone receptor positive (HR+)/HER2-, HR+/HER2+, HR-/HER2+, and triple-negative (TN) breast cancer were 75.4% (46/61), 82.6% (19/23), 85.2% (23/27), and 94.6% (35/37), respectively (P < 0.001). The rates of ypN0 in TN and HER2+ patients were 94.6% and 95.5%, which were significantly higher than that in HR+/HER2- patients (P < 0.05). Molecular subtypes, clinical stage, radiologic complete response, and pathologic complete response (bpCR) of the breast tumor correlated with ypN0 after full-course NAC (P < 0.05). Molecular subtypes (OR = 2.374, P = 0.033), clinical stage (OR = 0.320, P = 0.029), and bpCR (OR = 0.454, P = 0.012) were independent predictors for ypN0. The optimal time of SLNB and NAC in cN0 patients might be different among different molecular subtypes: it would be preferable to perform SLNB prior to NAC for HR+/HER2- patients, and SLNB after NAC for TN and HER2+ patients to reduce the risk of axillary lymph node dissection. In view of the high ypN0 rate in cN0 patients, axillary surgical staging might be selectively eliminated, especially for HER2+ and TN patients.

3.
J Cell Physiol ; 234(12): 23349-23359, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31169309

RESUMO

Long noncoding RNAs (lncRNAs) have been implicated in the regulation of resistance to radiotherapy in cervical cancer, which is a type of gynecological disease with high mortality in women around the world. Hence, our purpose is to delineate the involvement of LINC00958 in regulating cell sensitivity to radiotherapy in cervical cancer. LINC00958 expression in cervical cancer was assayed, followed by verification of the relationship among LINC00958, microRNA-5095 (miR-5095) and ribonucleotide reductase subunit M2 (RRM2). Hela cells were transduced with up-/downregulation of miR-5095 or RRM2, or LINC00958 silencing, respectively, and then treated with or without a 6 Gy dose of X-ray irradiation. Then the cell proliferation, apoptosis, survival fraction rate, as well as sensitivity to radiotherapy, were assessed. Finally, xenograft tumor in nude mice was established by transplanting Hela cells transfected with sh-LINC00958 and irradiated with 6 Gy of X-ray. High expression of LINC00958 was revealed in The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis, as well as in radiation-resistant patients, which was associated with lower sensitivity to radiotherapy in cervical cancer. Moreover, cervical cancer patients with higher LINC00958 expression exhibited a shorter overall survival according to Kaplan-Meier analysis. In addition, LINC00958 could regulate the expression of RRM2 by competing for miR-5095. A combination of radiotherapy with LINC00958 silencing, RRM2 downregulation or miR-5095 overexpression was found to inhibit cervical cancer cell proliferation and tumor growth, while promoting cell apoptosis both in vitro and in vivo. Collectively, our results suggest that LINC00958 could regulate RRM2 by competing to miR-5095, which regulates cell sensitivity to radiotherapy in cervical cancer.

4.
J Cell Physiol ; 234(12): 22331-22342, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31140597

RESUMO

Ovarian cancer characterizes as the fourth leading consequence of death associated with cancer for women. Accumulating evidence underscores the vital roles of microRNAs (miRNAs) in preventing ovarian cancer development. Besides, induction of the phosphatidylinositol-3 kinase/serine/threonine kinase (PI3K/Akt) pathway associated with the ovarian cancer cell migration and invasion. The study aims to examine the effects of miR-15b on the proliferation, apoptosis, and senescence of human ovarian cancer cells by binding to lysophosphatidic acid receptor 3 (LPAR3) with the involvement of the PI3K/Akt pathway. The positive expression of LPAR3 protein was detected by immunohistochemistry. Then the interaction between miR-15b and LPAR3 was examined. The possible role of miR-15b in ovarian cancer was explored using gain- and loss-of-function experiments. Subsequently, the functions of miR-15b on PI3K/Akt pathway, proliferation, migration, invasion, senescence and apoptosis of ovarian cancer cells were assessed. Furthermore, in vivo tumorigenicity assay in nude mice was performed. LPAR3 was overexpressed, whereas miR-15b was poorly expressed in ovarian cancer tissues. LPAR3 is a direct target of miR-15b. Restored miR-15b promoted Bax expression, apoptosis, and senescence, inhibited expression of LPAR3 and Bcl-2, the extent of PI3K and Akt phosphorylation, as well as ovarian cancer cell proliferation, migration, and invasion. Further, tumor growth was observed to be prevented by miR-15b overexpression. Collectively, our study demonstrates that miR-15b represses the proliferation and drives the senescence and apoptosis of ovarian cancer cells through the suppression of LPAR3 and the PI3K/Akt pathway, highlighting an antitumorigenic role of miR-15b.

5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(2): 145-151, 2019 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-31106530

RESUMO

OBJECTIVE: To test the killing effect of type Ⅰ receptor tyrosine kinase-like orphan receptor (ROR1) chimeric antigen receptor T cell (CAR-T) on several ROR1-expressing tumor cells in vitro. METHODS: The CAR gene was designed and synthesized by constructing the lentiviral vector plasmid, and BamHⅠ/EcoRⅠ was used to identify the plasmid. The expression levels of ROR1 among a variety of tumor cell lines were compared using flow cytometry (FCM). The killing effect of CAR-T on positive cells was detected by FCM, the LDH assay and ELISA. RESULTS: The double enzyme digestion identified CAR gene was successfully constructed to the lentivirus vector plasmid. FCM detection showed that the efficiency of CAR-T infection was about 47.23%. Multiple tumor cells expressed ROR1 in varying degrees. The FCM and the LDH assay indicated that CAR-T specifically killed ROR1-positive tumor cells. On positive target cells, more interferonI-γ (FN-γ) could be released during the CAR-T killing process than control T (P<0.05). CONCLUSION: We successfully constructed ROR1 CAR-T. CAR-T can specifically kill ROR1-positive tumor cells and cause the release of large amounts of IFN-γ, providing an experimental basis for clinical application.


Assuntos
Imunoterapia Adotiva , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/imunologia , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos Quiméricos , Linfócitos T/citologia , Linhagem Celular Tumoral , Humanos , Lentivirus
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(1): 1-6, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31037897

RESUMO

OBJECTIVE: To determine the effect of apurinic/apyrimidinic endonuclease-1(APE1) on the radiosensitivity of non-small cell lung cancer cells. METHODS: The expression of APE1 was detected by immunohistochemistry in 20 surgical specimen of non-small cell lung cancer tissues and 5 cases of pericarcinous lung tissues.The expressions of APE1 protein and mRNA in non-small cell lung cancer cell lines(A549, H460, H1299)and normal lung epithelial cell lines was detected by Western blot and qRT-PCR. The A549 and H460 stable cell lines with silencing of APE1 were constructed.The expression of APE1 in the silenced and non-silenced cells after exposure to 0-6 Gy radiation was detected by Western blot. The effect of silencing of APE1 was measured by colony formation assay, the proliferation of non-small cell lung cancer cells detected by CCK-8 assay, and the apoptosis of non-small cell lung cancer cells detected by Annexin Ⅴ/PI flow cytometry. RESULTS: The expression of APE1 was upregulated in non-small cell lung cancer tissues and cell lines.Radiation induced the expression of APE1 in non-small cell lung cancer cells in a dose responsive way. The silencing of APE1 inhibited the expression of APE1 induced by radiation in A549 and H460 cells. Exposure to radiation of the cells with silenced APE1 further inhibited cell colony formation and cell proliferation, and promoted the apoptosis of non-small cell lung cancer cells ( P<0.05). CONCLUSION: Silencing of APE1 enhances the radiosensitivity of non-small cell lung cancer cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Neoplasias Pulmonares , Apoptose , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/radioterapia , Tolerância a Radiação
7.
Insect Sci ; 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30869181

RESUMO

Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) is a major pathogen of the economic insect silkworm, Bombyx mori. Virus-encoded microRNAs (miRNAs) have been proven to play important roles in host-pathogen interactions. In this study we identified a BmCPV-derived miRNA-like 21 nt small RNA, BmCPV-miR-1, from the small RNA deep sequencing of BmCPV-infected silkworm larvae by stem-loop quantitative real-time PCR (qPCR) and investigated its functions with qPCR and lentiviral expression systems. Bombyx mori inhibitor of apoptosis protein (BmIAP) gene was predicted by both target prediction software miRanda and Targetscan to be one of its target genes with a binding site for BmCPV-miR-1 at the 5' untranslated region. It was found that the expression of BmCPV-miR-1 and its target gene BmIAP were both up-regulated in BmCPV-infected larvae. At the same time, it was confirmed that BmCPV-miR-1 could up-regulate the expression of BmIAP gene in HEK293T cells with lentiviral expression systems and in BmN cells by transfecting mimics. Furthermore, BmCPV-miR-1 mimics could up-regulate the expression level of BmIAP gene in midgut and fat body in the silkworm. In the midgut of BmCPV-infected larvae, BmCPV-miR-1 mimics could be further up-regulated and inhibitors could lower the virus-mediated expression of BmIAP gene. With the viral genomic RNA segments S1 and S10 as indicators, BmCPV-miR-1 mimics could up-regulate and inhibitors down-regulate their replication in the infected silkworm. These results implied that BmCPV-miR-1 could inhibit cell apoptosis in the infected silkworm through up-regulating BmIAP expression, providing the virus with a better cell circumstance for its replication.

8.
Thorac Cancer ; 10(4): 1023-1028, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30775851

RESUMO

EGFR-activating mutations have been recognized as the most important predictor of response to EGFR-tyrosine kinase inhibitors (TKIs); however, 20-30% of patients harboring EGFR-activating mutations show poor responses. The mechanisms of such EGFR-TKI primary resistance are still poorly understood. In our case, a non-small cell lung cancer patient developed intrinsic EGFR-TKI resistance and was then confirmed to simultaneously harbor an L858R mutation and ROS1 rearrangement. Salvage chemotherapy plus Endostar showed enduring therapeutic effects, achieving a disease-free survival period of 24 months and overall survival of 30 months. This suggests that co-activation of different oncogenic signal pathways might be a potential mechanism of EGFR-TKI primary resistance. Chemotherapy combined with anti-angiogenesis should be considered an important salvage strategy. Further studies are warranted to verify these findings and explore the underlying mechanisms involved.

9.
Hum Gene Ther ; 30(4): 402-412, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30693795

RESUMO

Chimeric antigen receptor-modified T cells (CAR-T cells) have emerged as a promising cancer immunotherapy for solid tumors. Epithelial cell adhesion molecule (EpCAM) is overexpressed in a variety of tumors and is recognized as a biomarker for circulating tumor cells and cancer stem cells, representing an attractive target for adoptive T-cell immunotherapy. This study generated third-generation CAR-T cells with redirected specificity to EpCAM (EpCAM CAR-T) by lentiviral vector. The study demonstrated that EpCAM CAR-T cells can elicit lytic cytotoxicity to target cells in an EpCAM-dependent manner and secrete cytotoxic cytokines, including interferon gamma and tumor necrosis factor alpha. Furthermore, adoptive transfer of EpCAM CAR-T cells significantly delayed tumor growth and formation in xenograft models. In addition, the safety evaluation showed that CAR-T cells have no systemic toxicity in mice. The data confirmed the antitumor ability and safety of CAR-T cells targeting EpCAM and may provide a new target for CAR-T cell therapies in treating solid tumors.

10.
Environ Mol Mutagen ; 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30499614

RESUMO

Fluorene-9-bisphenol (BHPF), a substitute of bisphenol A (BPA) used in the production of the so-called "BPA-free" plastics, has now been shown to be released from commercial plastic bottles into drinking water and has strong anti-estrogenic activity in mice, which suggests that BHPF is also an environmental toxin. However, whether BHPF exposure has effects on mouse oocyte development is unknown. In this study, the influence of acute exposure to BHPF (50-150 µM, 12 hr) on mouse oocyte maturation and its possible mechanisms were investigated. Of note, 50-µM BHPF had no effects on the maturation of mouse oocytes, whereas 100- and 150-µM BHPF significantly blocked germinal vesicle breakdown and led to the failure of first polar body extrusion. Particularly, 100-µM BHPF exposure severely decreased the cellular adenosine triphosphate in a time-dependent manner, which finally brought out the loss of spindles. In addition, the actin cytoskeleton was also impaired. The defective mitochondrial dynamics and decreased mitochondrial DNA implied the damage of mitochondria in BHPF-treated oocytes. Increased PINK1, Beclin1, and LC3B protein level and decreased TOMM20 and TOMM17A protein level illustrated that mitophagy was induced, which also confirmed that BHPF exposure impaired the cellular mitochondria. Moreover, BHPF induced reactive oxygen species accumulation and early apoptosis. Oocyte quality was also impaired by BHPF exposure through altering histone modifications evidenced by increased H3K9me3 and H3K27me3 levels. Collectively, our results indicated that BHPF exposure disrupted mouse oocyte maturation and reduced oocyte quality through affecting cytoskeleton architecture, mitochondrial function, oxidative stress, apoptosis, and histone modifications. Environ. Mol. Mutagen. 2018. © 2018 Wiley Periodicals, Inc.

11.
J Cell Biochem ; 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30520140

RESUMO

Polycystic ovary syndrome (PCOS), known as a common endocrine disorder among females, plagues many PCOS patients. The current study aimed to explore the correlations of sex hormone-binding globulin (SHBG) polymorphisms with the outcome of in vitro fertilization-embryo transfer (IVF-ET) in PCOS patients. PCOS patients who underwent IVF-ET and patients with non-PCOS-related infertility were selected in the study. Correlations of SHBG rs6259 and rs727428 with the risk factors in PCOS were analyzed, followed by the evaluation of the effect of SHBG polymorphisms on the outcome of IVF-ET in PCOS patients. At last, unconditional logistic regression analysis was performed to study the risk factors for IVF-ET treatment outcome. Compared with SHBG rs6259 GG carriers, the incidence of PCOS was found to be elevated in SHBG rs6259 GA+AA carriers which indicated that the A allele was a risk factor for PCOS. Compared with SHBG rs6259 TT carriers, the number of retrieved oocytes and embryo as well as the fertility rate in SHBG rs6259 GA+AA carriers was found to be decreased, while the abortion rate, incidence of ovarian hyperstimulation syndrome, transplant rejection rate, estradiol, and testosterone in serum, as well as testosterone in follicular fluid were elevated. The luteal hormone, serum testosterone, and progesterone and GA+AA genotype of rs6259 were the risk factors for IVF-ET treatment outcome. Taken together, the study showed that SHBG rs6259 polymorphisms might be correlated with the risk of PCOS and the outcome of IVF-ET treatment.

12.
World J Cardiol ; 10(11): 222-233, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30510639

RESUMO

AIM: To establish whether frequency-domain optical coherence tomography (FD-OCT) is safe and effective in the evaluation and treatment of angiographically-intermediate coronary lesions (ICL). METHODS: Sixty-four patients with 2-dimensional quantitative coronary angiography (2D-QCA) demonstrating ICL were included. OCT imaging was performed. According to predetermined OCT criteria, patients were assigned to either of 2 groups: OCT-guided percutaneous coronary intervention (PCI) or OCT-guided optimal medical therapy (OMT). The primary efficacy endpoint was to demonstrate the superiority and higher accuracy of FD-OCT compared to 2D-QCA in evaluating stenosis severity in patients with ICL. The primary safety endpoint was the incidence of 30-d major adverse cardiac events (MACE). Secondary endpoints included MACE at 12 mo and other clinical events. RESULTS: Analysis of the primary efficacy endpoint demonstrates that 2D-QCA overestimates the stenosis severity of ICL in both the OCT-guided PCI and OMT groups, proving FD-OCT to be superior to and more precise than 2D-QCA in treating this subset of lesions. The primary safety endpoint was fully met with the incidence of 30-d MACE being nil in both the OCT-guided PCI and OCT-guided OMT groups. Incidences of secondary endpoints were found to be low in both arms, the only exception being the relatively high incidence of recurrent episodes of angina which was, however, very similar in the 2 groups. CONCLUSION: FD-OCT is safe and effective in the evaluation and treatment of ICL. Larger studies are needed to firmly establish the efficacy and safety of FD-OCT in treating ICL across all coronary artery disease population subgroups.

14.
Mikrochim Acta ; 185(10): 483, 2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30269212

RESUMO

The authors report on a one-pot approach for synthesizing highly fluorescent protamine-stabilized gold nanoclusters. These are shown to be a viable nanoprobe for selective and sensitive fluorometric determination of lead(II) via quenching of fluorescence via Pb(II)-Au(I) interaction. Under optimized conditions, fluorescence measured at excitation/emission peaks of 300/599 nm drops in the 80 nM-15 µM lead(II) concentration range. The detection limit is 24 nM, and relative standard deviations (for n = 11) at concentrations of 0.10, 4.0 and 15 µM are 1.6, 2.5 and 1.9%, respectively. The relative recoveries of added lead(II) in the water samples ranged from 97.9 ± 2.29% to 101.2 ± 1.83%. Graphical abstract Lead(II) ions are found to be able to selectively and sensitively quench the fluorescence of the protamine-gold nanoclusters (PRT-AuNCs). Thereby, an inexpensive, selective and sensitive lead(II) assay was established.

15.
Exp Cell Res ; 371(2): 435-443, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30195030

RESUMO

Nucleoporins (Nups) are a large and diverse family of proteins that mediate nucleocytoplasmic transport at interphase of vertebrate cells. Nups also function in mitosis progression. However, whether Nups are involved in oocyte meiosis progression is still rarely known. In this study, we delineated the roles and regulatory mechanisms of Nucleoporin35 (Nup35) during oocyte meiotic maturation. The immunofluorescent signal of Nup35 was localized in the nuclear membrane at germinal vesicle (GV) stage, the microtubules and spindle at pro-metaphase I (pro-MI), metaphase I (MI), and metaphase II (MII), but to the spindle poles at anaphase I (AI) and telophase I (TI). The dynamic localization pattern of Nup35 during oocyte meiotic maturation implied its specific roles. We also found that Nup35 existed as a putatively phosphorylated form after resumption of meiosis (GVBD), but not at GV stage, implying its functional switch from nuclear membrane to meiotic progression. Further study uncovered that knockdown of Nup35 by specific siRNA significantly compromised the extrusion of first polar body (PBE), but not GVBD, with defects of spindle assembly and chromosome alignment and dissociated some localization signal of p-ERK1/2 from spindle poles to cytoplasm. A defective kinetochore - microtubule attachment (K-MT) was also identified in oocytes after knockdown of Nup35, which activates spindle assembly checkpoint. In conclusion, our results suggest that Nup35 is putatively phosphorylated and released to the cytoplasm after resumption of meiosis, and regulates spindle assembly and chromosome alignment.

16.
Artigo em Inglês | MEDLINE | ID: mdl-30265431

RESUMO

OBJECTIVES: We aimed to assess the effect of selective intracoronary hypothermia on outcomes in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). BACKGROUND: Intracoronary hypothermia, the feasibility and safety of which has been validated in humans, induced by selective trans-coronary infusion of saline at different temperatures can reduce infarct size (IS) prior to reperfusion in animal models of STEMI. METHODS: Sixty STEMI patients presenting with thrombolysis in myocardial infarction (TIMI) flow grade 0/1 were randomized after coronary artery angiography. Intracoronary hypothermia was induced by selective trans-coronary infusion of saline at 4°C to the endangered myocardium in the 30 patients. The primary endpoint, absolute IS expressed as IS/myocardium at risk (MaR), was assessed by cardiac magnetic resonance imaging at day 7 post-PPCI in 50 patients. Clinical follow-up was undertaken at day 30 after procedure. RESULTS: Intracoronary hypothermia was successfully performed in hypothermia group, without increase in arrhythmia or hemodynamic instability. The mean temperature reduction of 5.8 ± 1.1°C in distal coronary artery was achieved before reperfusion. Mean IS/MaR was predominantly reduced in the hypothermia group (44.85 ± 5.89% vs. 50.69 ± 10.75%, P = 0.022), especially in the anterior STEMI subgroup (46.12 ± 7.54% vs. 55.27 ± 11.175%, P = 0.023). The clinical events appeared no statistical difference between the two groups at the 30-day follow-up. CONCLUSION: The statistical difference in IS/MaR by intracoronary hypothermia as adjunctive therapy to PPCI is an important observation and warrants a larger pivotal trial fully powered for efficacy.

17.
Anal Bioanal Chem ; 410(28): 7385-7394, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30215122

RESUMO

We certify that protamine-gold nanoclusters (PRT-AuNCs) synthesized by one-pot method exhibit peroxidase-like activity. The catalytic activity of PRT-AuNCs followed typical Michaelis-Menten kinetics and exhibited higher affinity to 3,3',5,5'-tetramethylbenzidine (TMB) as the substrate compared to that of natural horseradish peroxidase. Meanwhile, we found that Hg(II) could dramatically and selectively enhance the peroxidase-like activity of PRT-AuNCs, and the enhanced mechanism by Hg(II) was demonstrated to be generation of the cationic Au species and the partly oxidized Au species (Auδ+) by Hg2+-Au0/Au+ interaction. Based on this finding, quantitative determinations of Hg(II) via visual observation and absorption spectra were achieved. The proposed strategy displays high selectivity that arises from the strong aurophilic interaction of mercury towards gold. Moreover, the developed method is highly sensitive with a wide linear range and low detection limit of 1.16 nM. This strategy is not only helpful to develop effective nanomaterials-based artificial enzyme mimics but also irradiative to discover new applications of artificial mimic enzymes in bio-detection, medical diagnostics, and biotechnology. Graphical abstract Protamine-gold nanoclusters (PRT-AuNCs) synthesized by one-pot method exhibit peroxidase-like activity. Hg(II) can stimulate the peroxidase-like activity of PRT-AuNCs selectively, enhancing their ability to catalyze the chromogenic reaction of TMB by H2O2.


Assuntos
Colorimetria/métodos , Ouro/química , Mercúrio/química , Nanopartículas Metálicas/química , Peroxidases/metabolismo , Protaminas/química , Cinética , Peroxidases/química , Sensibilidade e Especificidade
18.
Oxid Med Cell Longev ; 2018: 9741838, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050663

RESUMO

Pseudomonas aeruginosa (PA) is one of the most prevalent pathogens that cause nosocomial infection in critical patients. However, the mechanisms underlying macrophage growth status and functional changes during PA infection are yet unknown. In the present study, NADPH oxidase, gp91phox (NOX2) mediated macrophage to senescence in a PAO1 colony-dependent manner. gp91phox might regulate the senescence process through mutual interaction with the NF-κB pathway. During infection, the overexpression or downregulation of gp91phox in macrophage could affect the nuclear activity of NF-κB p65, while the downregulation of NF-κB p65 led to a suppressed expression of gp91phox. Reactive oxygen species (ROS) served as the second messenger between both molecules as the ROS inhibitor, N-acetylcysteine (NAC), could partially restore these changes. Consequently, the level of ROS and inflammatory cytokines, including IL-6 and TNFα, elevated during PAO1 infection, and their production altered as a result of the genetic manipulation of gp91phox and NF-κB p65, as well as NAC treatment. Also, the senescent phenotypes, SA-ß-gal staining and p16ink4a, changed after genetic manipulation with gp91phox and NF-κB p65 and NAC treatment. The capacity of phagocytosis in macrophages was decreased during senescence. In conclusion, PA directs the macrophage towards senescence, and senescent macrophages exhibit a decreased ability of phagocytosis. This process of senescence was regulated by the interactions between NADPH oxidase gp91phox and NF-κB p65 via ROS as a second messenger.


Assuntos
Macrófagos/citologia , Macrófagos/metabolismo , NADPH Oxidase 2/metabolismo , NF-kappa B/metabolismo , Infecções por Pseudomonas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/metabolismo , Animais , Senescência Celular/fisiologia , Humanos , Interleucina-6/metabolismo , Pseudomonas aeruginosa/patogenicidade , Fator de Necrose Tumoral alfa/metabolismo
19.
Neurochem Res ; 43(8): 1575-1586, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948728

RESUMO

The aim of the study was to elucidate the therapeutic effects of Cytisine (CYT) on cerebral ischemia-reperfusion injury in mice. Male ICR mice were pretreated with reagents (drug), and then subjected to 2 h focal cerebral ischemia and 24 h reperfusion. Morphologically, the histopathological impairment were estimated by the TTC, HE and TUNEL staining. The expression of GluN2B-containing NMDA receptor, phosphorylation of extracellular regulated protein kinases, total ERK, phosphorylation of cAMP-response element binding protein and total CREB were determined by immunofluorescence and Western blot assay, respectively. The mRNA expression of NR2B, ERK and CREB were quantified by the real-time RT-PCR. CYT significantly diminished the infarct size and neuronal apoptosis. Additionally, it ameliorated histopathological lesion dramatically. CYT promoted the phosphorylation of ERK, CREB and their mRNA expression. In contrast, the expression of NR2B was suppressed in concomitant with the down-regulation of genes. The overall results thus far suggest that CYT confers the neuroprotection against cerebral I/R injury by regulating the NR2B-ERK/CREB signal pathway.


Assuntos
Alcaloides/uso terapêutico , Isquemia Encefálica/prevenção & controle , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Alcaloides/química , Alcaloides/farmacologia , Animais , Azocinas/química , Azocinas/farmacologia , Azocinas/uso terapêutico , Isquemia Encefálica/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neuroproteção/efeitos dos fármacos , Neuroproteção/fisiologia , Quinolizinas/química , Quinolizinas/farmacologia , Quinolizinas/uso terapêutico , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
20.
Cancer Res Treat ; 2018 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-29890814

RESUMO

Purpose: The purpose of this study was to detect the lymphatic drainage pattern of internal mammary area and verify the concept of internal mammary sentinel lymph node (IM-SLN) in breast. Materials and Methods: A small particle radiotracer (99mTc-Dextran 40) was prepared and tested. 99mTc-Dextran 40 was injected into intraparenchyma at the sound breast by a modified radiotracer injection technique. Subsequently, dynamic single-photon emission computed tomography (SPECT), computed tomography (CT), and SPECT/CT combination images were performed to identify the radioactive lymph vessels and internal mammary lymph nodes (IMLNs). The direction of lymph drainage and the location of the IMLNs were identified in the SPECT/CT imaging. Results: The radiochemical purity of 99mTc-Dextran 40 was >95%. 99mTc-Dextran 40 could drainage into first, second, and third lymph node and the radioactive lymph node could be detected by the γ detector in the animal experiment. After 99mTc-Dextran 40 injecting into intraparenchyma, 50.0% cases (15/30) were identified the drainage lymphatic vessels and radioactive IMLNs by SPECT. The drainage lymphatic vessel was found from injection point to the first IMLN (IM-SLN) after 10.5±0.35 minutes radiotracer injection, and then 99mTc-Dextran 40 was accumulated into the IM-SLN. The combination imaging of SPECT/CT showed the second IMLN received the lymph drainage from the IM-SLN. The lymphatic drainage was step by step in the internal mammary area. Conclusion: The lymph was identified to drain from different regions of the breast to IM-SLN, and then outward from IM-SLN to other IMLN consecutively. It demonstrated the concept of the IM-SLN and provided more evidences for the application of internal mammary sentinel lymph node biopsy.

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