Covalent Amide-Bonded Nanoflares for High-Fidelity Intracellular Sensing and Targeted Therapy: A Superstable Nanosystem Free of Nonspecific Interferences.

A nanoflare, a conjugate of Au nanoparticles (NPs) and fluorescent nucleic acids, is believed to be a powerful nanoplatform for diagnosis and therapy. However, it highly suffers from the nonspecific detachment of nucleic acids from the AuNP surface because of the poor stability of Au-S linkages, thereby leading to the false-positive signal and serious side effects. To address these challenges, we report the use of covalent amide linkage and functional Au@graphene (AuG) NP to fabricate a covalent conjugate system of DNA and AuG NP, label-rcDNA-AuG. Covalent coating of abundant amino groups (-NH2) onto the graphitic shell of AuG NP efficiently facilitates the coupling with carboxyl-labeled capture DNA sequences through simple, but strong, amide bonds. Importantly, such an amide-bonded nanoflare possesses excellent stability and anti-interference capability against the biological agents (nuclease, DNA, glutathione (GSH), etc.). By accurately monitoring the intracellular miR-21 levels, this covalent nanoflare is able to identify the positive cancer cells even in a mix of cancer and normal cells. Moreover, it allows for efficient photodynamic therapy of the targeted cancer cells with minimized side effects on normal cells. This work provides a facile approach to develop a superstable nanosystem showing promising potential in clinical diagnostics and therapy.

Shell-Switchable SERS Blocking Strategy for Reliable Signal-On SERS Sensing in Living Cells: Detecting an External Target without Affecting the Internal Raman Molecule.

For SERS analysis in living cells, the inevitable desorption of Raman molecule on the substrate surface is a key challenge. To ensure high stability, SERS systems with Raman molecules protected inside the core-Raman molecule-shell (C-M-S) structures have been designed, but at the expense of sacrificed sensing performances. Here a shell-switchable SERS blocking strategy is developed for the reliable SERS analysis in living cells, relying on the shell blockers to regulate the SERS sensing signal without affecting the internal Raman molecules. After several C-M-S structures were investigated, the SERS blocking mechanism confirmed that thick shells (Au, Ag, ZnO, and MnO2) can cause a significant reduction in the internal SERS signal by obstructing the penetration of the laser or signal. The CAu-Mpy-SAu-SMnO2 nanoprobe is designed for the ratiometric SERS sensing in living cells, which retains sensing performances even though the Raman molecule is protected inside the nanostructure. This SERS strategy makes the turn-on sensing achievable in living cells with the MnO2 shell as a signal switch and a Raman reference. Additionally, it allows for accurate monitoring of the degradation of MnO2 carriers in living cells, even without fluorescent labels.

Concomitant activation of functionally opposing prostacyclin and thromboxane prostanoid receptors by cyclo-oxygenase-1-mediated prostacyclin synthesis in mouse arteries.

This study aimed to determine whether cyclo-oxygenase-1 (COX-1) mediates dilatation of mouse arteries via synthesis of prostacyclin (PGI(2)) and, if so, how PGI(2) (IP) receptors contribute and whether thromboxane prostanoid (TP) receptors are implicated in the process. Mesenteric arteries were isolated from wild-type mice or mice with COX-1 deficiency (COX-1(-/-)). The vasomotor reaction to the COX substrate arachidonic acid (AA) was determined with isometric force measurement, while the in vitro production or the plasma level of the PGI(2) metabolite 6-keto-PGF(1α) was analysed with high-performance liquid chromatography-mass spectroscopy or enzyme immunoassay, respectively. Results showed that AA, which evoked endothelium-dependent 6-keto-PGF(1α) production, elicited relaxation that was inhibited or enhanced by antagonizing IP or TP receptors, respectively. Also, IP receptor blockade resulted in contraction in response to AA (following NO synthase inhibition), which was prevented by a concomitant TP receptor antagonism. Meanwhile, COX-1(-/-) or COX-1 inhibition abolished the in vitro 6-keto-PGF(1α) production and reduced the relaxation or contraction observed with AA. Real-time PCR showed that whereas TP receptor mRNAs were detected at similar levels, IP receptor mRNAs were present at higher levels in the branches than in the main stem of the mesenteric artery. In addition, antagonizing the IP receptors enhanced the contraction evoked by PGI(2) in the carotid artery. Also, we noted that COX-1(-/-) mice had a reduced basal plasma 6-keto-PGF(1α) level. These results demonstrate an explicit vasodilator role for COX-1-mediated endothelial PGI(2) synthesis and suggest that the functionally opposing IP and TP receptors concomitantly mediate the vasomotor reaction to PGI(2), with the dilator activity of IP receptors being compromised by the vasoconstrictor effect of TP receptors and vice versa.

The effects of social defeat stress on hippocampal glial cells and interleukin-6 in adolescence and adulthood.

Adolescent social stress has been associated with the vulnerability to developing psychopathological disorders in adulthood that are accompanied by brain inflammatory processes. The purpose of this study is to investigate the dynamic changes of the hippocampal neuroinflammatory mediators, including microglia, astrocyte, and interleukin-6 (IL-6) levels in mice experiencing social defeat stress during adolescence. Adolescent mice were divided into the control group and stress group. Mice in the stress group were exposed to chronic intermittent social defeat for a total of 12 days, and control mice were reared in normal conditions. The hippocampal microglia, astrocyte, and IL-6 levels were measured 24 h and 3 weeks after the end of stress exposure. Microglia activation characterized by increased ionized calcium-binding adapter molecule 1 positive cell numbers or staining area in the CA1 and CA3 regions of the hippocampus were observed 24 h after the end of stress, which did not last into the adulthood. No short-term or long-term alterations of the number of hippocampal CA1 and CA3 glia fibrillary acidic protein astrocytes were found in mice experiencing adolescent social defeat, whereas IL-6 levels were only increased 3 weeks after the end of stress. These data suggested that exposure to chronic social defeat stress led to short-term and long-term neuroinflammatory changes in the hippocampus.

NUF2 as an anticancer therapeutic target and prognostic factor in breast cancer.

Breast cancer (BC) is the most frequently diagnosed type of cancer, and the leading cause of cancer­associated mortality in females worldwide. The aim of the present study was to investigate the prognostic and therapeutic potential of NUF2 in BC. The expression levels of NUF2 in BC tissues and cell lines were evaluated via bioinformatics, reverse transcription­quantitative PCR, western blot analysis and immunohistochemistry (IHC). In addition, the effect of NUF2 knockdown on BC cell proliferation and apoptosis was investigated using small interfering RNA (siRNA) technology. Bioinformatics and IHC analysis showed that NUF2 was overexpressed in BC tissues. Furthermore, western blot and RT­qPCR analyses demonstrated that NUF2 was upregulated in BC cells. In addition, BC cells transfected with NUF2 siRNA exhibited significantly decreased proliferation and colony formation, and increased apoptosis, compared with the control. Additionally, cell cycle analysis revealed that NUF2 induced G0/G1 cell cycle arrest by inhibiting cyclin B1 expression. Collectively, the present study suggested that NUF2 may represent a promising prognostic biomarker and a potential therapeutic target for BC.

The efficacy of gabapentin in reducing pain intensity and postoperative nausea and vomiting following laparoscopic cholecystectomy: A meta-analysis.

BACKGROUND: It is unknown whether gabapentin is effective in reducing acute pain following laparoscopic cholecystectomy. The purpose of the current meta-analysis was to evaluate the efficacy of gabapentin in reducing pain intensity and postoperative nausea and vomiting (PONV) after laparoscopic cholecystectomy. METHODS: All randomized controlled trials (RCTs) evaluating the efficacy of gabapentin in reducing pain intensity and PONV after laparoscopic cholecystectomy were searched on the following databases: PubMed, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), the Google database, the Chinese Wanfang database, and the China National Knowledge Infrastructure (CNKI). The most recent literature search was conducted on March 21, 2017. Outcomes including visual analog scale (VAS) at 12 and 24 hours, total morphine consumption, and the occurrence of PONV. Continuous outcomes were expressed as the weighted mean difference (WMD) and 95% confidence interval (CI), and the one discontinuous outcome was expressed as risk ratio (RR) and 95% CI. Stata 12.0 software was used for meta-analysis. RESULTS: A total of 9 studies involving 966 patients were identified. In total, there were 484 gabapentin subjects and 482 controls. Compared with the control group, gabapentin was associated with lower VAS at 12 hours (WMD = -10.18, 95% CI: -17.36 to -2.80, P = .007) and 24 hours (WMD = -6.33, 95% CI: -8.41 to -4.25, P = .000), which was equivalent on a 110-point VAS scale to 10.18 points at 12 hours and 6.33 points at 24 hours. Compared with the control group, gabapentin was associated with less total morphine consumption by approximately 110.83 mg (WMD = -110.83, 95% CI: -183.25 to -38.42, P = .003). In addition, the occurrence of nausea and vomiting in gabapentin was decreased (25.2% vs 47.6, RR = 0.53, 95% CI: 0.44-0.63, P = .000). CONCLUSION: Gabapentin was efficacious in reducing postoperative pain, total morphine consumption, and morphine-related complications following laparoscopic cholecystectomy. In addition, there was a negative correlation between the gabapentin dosage and the occurrence of nausea and vomiting. The number of included studies is limited, and more studies are needed to verify the effects of gabapentin in laparoscopic cholecystectomy patients.

miR141 expression is downregulated and negatively correlated with STAT5 expression in esophageal squamous cell carcinoma.

The aim of the present study was to investigate the association between microRNA-141 (miR141) and signal transducer and activator of transcription 5 (STAT5) expression levels in human esophageal squamous cell carcinoma (ESCC) and to investigate the effects of miR141 on ESCC cells. A total of 45 consecutive patients with ESCC were enrolled in the study. The expression of miR141 in ESCC tissue samples was detected using reverse transcription quantitative polymerase chain reaction (RT-qPCR). The expression of STAT5 in the ESCC tissues was detected using immunohistochemical staining and western blotting. In addition, Eca109 cells were transfected with miR141 mimic, and the levels of STAT5 were detected using western blotting. The effects of miR141 on the proliferation, invasion and migration of the cells were also detected using MTT, scratch and Transwell invasion assays, respectively. The miR141 expression level in the ESCC tissue samples was significantly decreased compared with that in the adjacent normal tissues (P<0.05). The expression of miR141 in the tissues from patients with lymph node metastasis was significantly decreased compared with that in the tissues of patients without such metastasis (P<0.05). The expression levels of STAT were significantly increased in the ESCC tissues compared with those in the adjacent normal tissues (P<0.05). Furthermore, the levels of STAT5 were significantly increased in the tissues from patients with lymph node metastasis compared with those without such metastasis (P<0.05); however, no statistically significant differences in miR141 expression were observed according to gender, age, tumor size, lesion location, differentiation and invasion (P>0.05). The results suggest that the miR141 mimic significantly inhibited the proliferation, migration and invasion of Eca109 cells in vitro. miR141 and STAT5 expression levels exhibited a negative association in the ESCC tissues, and were both closely associated with the progression of ESCC. Therefore, it appears that miR141 plays an important role in the development, invasion and metastasis of ESCC by regulating the expression of STAT5.

Vasomotor Reaction to Cyclooxygenase-1-Mediated Prostacyclin Synthesis in Carotid Arteries from Two-Kidney-One-Clip Hypertensive Mice.

This study tested the hypothesis that in hypertensive arteries cyclooxygenase-1 (COX-1) remains as a major form, mediating prostacyclin (prostaglandin I2; PGI2) synthesis that may evoke a vasoconstrictor response in the presence of functional vasodilator PGI2 (IP) receptors. Two-kidney-one-clip (2K1C) hypertension was induced in wild-type (WT) mice and/or those with COX-1 deficiency (COX-1-/-). Carotid arteries were isolated for analyses 4 weeks after. Results showed that as in normotensive mice, the muscarinic receptor agonist ACh evoked a production of the PGI2 metabolite 6-keto-PGF1α and an endothelium-dependent vasoconstrictor response; both of them were abolished by COX-1 inhibition. At the same time, PGI2, which evokes contraction of hypertensive vessels, caused relaxation after thromboxane-prostanoid (TP) receptor antagonism that abolished the contraction evoked by ACh. Antagonizing IP receptors enhanced the contraction to the COX substrate arachidonic acid (AA). Also, COX-1-/- mice was noted to develop hypertension; however, their increase of blood pressure and/or heart mass was not to a level achieved with WT mice. In addition, we found that either the contraction in response to ACh or that evoked by AA was abolished in COX-1-/- hypertensive mice. These results demonstrate that as in normotensive conditions, COX-1 is a major contributor of PGI2 synthesis in 2K1C hypertensive carotid arteries, which leads to a vasoconstrictor response resulting from opposing dilator and vasoconstrictor activities of IP and TP receptors, respectively. Also, our data suggest that COX-1-/- attenuates the development of 2K1C hypertension in mice, reflecting a net adverse role yielded from all COX-1-mediated activities under the pathological condition.