Dexmedetomidine reduces the neuronal apoptosis related to cardiopulmonary bypass by inhibiting activation of the JAK2-STAT3 pathway

Cardiopulmonary bypass (CPB) constitutes one of the primary methodologies pertaining to cardiac surgery. However, this form of surgery can cause damage to the body. Many studies have reported that dexmedetomidine confers cerebral protection. In this study, we aimed to investigate the effect and mechanism of dexmedetomidine on neuronal apoptosis caused by CPB. Here, rats were treated with different doses of dexmedetomidine by intravenous infusion 2 hours after CPB. We observed that dexmedetomidine treatment to rats reduces the S100β, NSE levels in plasma, and neuronal apoptosis following CPB in a dose-dependent manner. Furthermore, we observed that the beneficial effect of dexmedetomidine treatment following CPB was associated with a reduction in IL6, an inflammatory cytokine in plasma and cortex. Our results suggest that dexmedetomidine provides neuroprotective effects by inhibiting inflammation and reducing neuronal apoptosis. There was a correlation between the protective effect on the brain and the dose of dexmedetomidine. In addition, dexmedetomidine administration inhibits phosphorylation of JAK2 and STAT3 proteins in the hippocampus of rats 2 hours after CPB. Therefore, we speculate that the JAK2–STAT3 pathway plays an important role in the neuroprotective effects of dexmedetomidine following brain injury induced by CPB.

High throughput in vitro and in vivo screening of inland waters of Southern California

The impact of unmonitored contaminants, also known as contaminants of emerging concern (CECs), on freshwater streams remains largely uncharacterized. Water samples from 31 streams representing urban, agricultural and undeveloped (i.e., open space) land use in Southern California (USA) were analyzed for in vitro and in vivo bioactivity. The extent and magnitude of bioactivity screened using endocrine-responsive cell bioassays and a fish embryo screening assay were low. In contrast, a wider gradient of responses for the aryl hydrocarbon receptor (AhR) assay was observed, which was negatively correlated with a measure of benthic community structure. Both aromatic and non-aromatic CECs were tentatively identified in these samples, but polycyclic aromatic hydrocarbons (PAHs), known AhR agonists in urban environments, were not present at detectable levels. These results suggest that a combination of in vitro and in vivo show potential as screening techniques for biological condition in situ, but that more advanced, comprehensive analytical methods are needed to identify bioactive contaminants.

Novel allylated monocarbonyl analogs of curcumin induce mitotic arrest and apoptosis by reactive oxygen species-mediated endoplasmic reticulum stress and inhibition of STAT3

Curcumin is a promising active compound from a natural source and is extensively being tested in clinical trials because of its bio-functional properties. However, poor bioavailability has hampered its clinical application. Numerous attempts have been made in our laboratory to discover analogs of curcumin with enhanced bioavailability and superior pharmacological activity. In this study, we have investigated a new series of allylated monocarbonyl analogs of curcumin (MAC) and tested their effect on gastric cancer cells. Our results show six MAC that selectively targeted cancer cell lines to inhibit growth and induce apoptosis. This activity was achieved by generation of reactive oxygen species (ROS) by MAC. We selected one effective MAC (CA10) for further investigation and show that CA10 inhibits cell growth by causing G2/M cell cycle arrest and induction of apoptotic death. CA10 induced ROS generation and subsequent activation of endoplasmic reticulum (ER) stress and inhibition of signal transducer and activator of transcription 3 (STAT3) phosphorylation, inhibits cancer cell proliferation. These anti-tumor activities of CA10 were confirmed in gastric cancer xenografts. CA10 induced ROS, activated the ER stress pathway and inhibited STAT3 phosphorylation and gastric xenografts tumor growth in mice. Our studies provide experimental evidence that MAC CA10 effectively targets gastric cancer in preclinical models by enhancing ROS and ROS-mediated signaling.

Negative Differential Conductance & Hot-Carrier Avalanching in Monolayer WS2 FETs

The high field phenomena of inter-valley transfer and avalanching breakdown have long been exploited in devices based on conventional semiconductors. In this Article, we demonstrate the manifestation of these effects in atomically-thin WS2 field-effect transistors. The negative differential conductance exhibits all of the features familiar from discussions of this phenomenon in bulk semiconductors, including hysteresis in the transistor characteristics and increased noise that is indicative of travelling high-field domains. It is also found to be sensitive to thermal annealing, a result that we attribute to the influence of strain on the energy separation of the different valleys involved in hot-electron transfer. This idea is supported by the results of ensemble Monte Carlo simulations, which highlight the sensitivity of the negative differential conductance to the equilibrium populations of the different valleys. At high drain currents (>10 μA/μm) avalanching breakdown is also observed, and is attributed to trap-assisted inverse Auger scattering. This mechanism is not normally relevant in conventional semiconductors, but is possible in WS2 due to the narrow width of its energy bands. The various results presented here suggest that WS2 exhibits strong potential for use in hot-electron devices, including compact high-frequency sources and photonic detectors.

[The study of locating facial nerve precisely in middle ear surgery based on clinical anatomy]

Objective:To investigate the methods of locating facial nerve precisely in middle ear surgery through the observation and measurement of the facial nerve and surrounding anatomical structures and to provide reference for the middle ear surgery.Method:Combined surgical approach on 15 cases (30 sides) fresh adult cadaveric specimens were dissected, observed the characteristics of facial nerve and its shape and spatial relationship of the surrounding structures, and measured the distance between the facial nerve and its surrounding structures.Result:The shortest distance from the midpoint of the posterior wall of external auditory canal (annulus level) to the vertical segment of the facial nerve was (3.37±0.34)mm, the shortest distance from the leading edge of the sigmoid sinus to the vertical segment of facial nerve was (7.40±0.71)mm, the shortest distance from the lateral margin of jugular bulb to the facial nerve was (5.58±0.79)mm, the shortest distance from Henle crest to the pyramidal segment of facial nerve was (12.76±1.24)mm, the shortest distance between the pyramidal segment of facial nerve and the posterior short limb of incus was (1.56±0.35)mm, the shortest distance between the pyramidal segment of facial nerve and the lower edge of posterior semicircular canal was (2.56±0.41) mm, the shortest distance between the lower edge of horizontal semicircular canal and the horizontal segment of facial nerve was (1.28±0.32) mm, the shortest distance between the upper edge of vestibular window and the horizontal segment of facial nerve was (0.67±0.15)mm.Conclusion:A good command of the anatomy of temporal bone as well as the methods of locating facial nerve will provide the key to reduce the probability of iatrogenic facial nerve injury in middle ear surgery.

Robotic vs. laparoscopic vs. open abdominoperineal resection for low rectal cancer: Short-term outcomes of a single-center prospective randomized controlled trial

3603

Background: Currently, robotic surgery for rectal cancer using da Vinci System is common. However, there is almost no clinical trial reported. This randomized controlled trial aims to compare the safety and efficacy of robotic, laparoscopic and open abdominoperineal resection (APR) for low rectal cancer. Methods: From September 2013 to August 2016, patients aged from 18 to 75 years, with low rectal cancer within 5 cm from anal verge, clinical T1 to T3, no distant metastases, were randomly assigned to receive either robotic procedures (RAP), laparoscopic procedures (LAP) or open surgery (OS) for APR in 1:1:1 ratio. The primary endpoint was postoperative complication rate. This study is registered with ClinicalTrials.gov (NCT01985698). Results: Totally 406 patients were randomly assigned. Actually, 135 finished RAP, 131 finished LAP, and 137 finished OS (including 4 convert from LAP to OS). RAP had significantly lower postoperative complication rate (11.1%) than both LAP (21.4%, P = 0.023) and OS (27.7%, P = 0.001). Also, RAP reduced intraoperative hemorrhage (median [interquartile range], 100 [90-110] ml) than LAP (130 [100-150] ml, P < 0.001) and OS (150 [120-260] ml, P < 0.001). And RAP promoted postoperative recovery, with shorter days to first flatus (1.0 [1.0-2.0] day) than LAP (2.0 [2.0-3.0] day, P < 0.001) and OS (3.0 [2.0-4.0] day, P < 0.001), shorter days to first automatic urination (2.0 [2.0-3.0] day) than LAP (3.0 [2.0-4.0] day, P < 0.001) and OS (3.0 [2.0-4.0] day, P < 0.001), and shorter days to discharge (5.0 [5.0-6.0] days) than LAP (6.0 [5.0-7.0] days, P < 0.001) and OS (6.0 [5.0-7.0] day, P = 0.005). There was no significant difference in open conversion rate, resection margin involvement (including circumferential resection margin), number of lymph node harvested and pathological tumor stage. Conclusions: Robotic APR was safer, and reproduce equivalent surgical quality of conventional laparoscopic and open surgery. Also, it provided less injury and faster functional recovery. Clinical trial information: NCT01985698.

Contrast-enhanced ultrasound in the diagnosis of orbital space-occupying lesions

AIM

To summarise the sonographic findings and assess the feasibility of contrast-enhanced ultrasound (CEUS) as an imaging method for the diagnosis of orbital space-occupying lesions.

MATERIALS AND METHODS

This was a prospective study of 53 patients who underwent orbital ultrasound at Xijing Hospital. Two-dimensional ultrasound, colour Doppler flow imaging (CDFI), and CEUS imaging were obtained and compared in patients with orbital haemangioma, pseudotumour, melanoma of the choroid, and retinoblastoma.

RESULTS

CEUS imaging cannot only visualise the location, shape, border, acoustic properties of a lesion, and interactions between the lesion and surrounding tissues, but also display the microvasculature and tissue perfusion within the lesion. The information obtained from CEUS imaging is valuable for diagnosis and differential diagnosis of orbital space-occupying lesions.

CONCLUSION

CEUS imaging allowed better visualisation of the lesions, enabled detection of vascular changes, increased the signal-to-noise ratio, and increased the sensitivity of detection of changes in perfusion in the microcirculation. It has relatively high sensitivity and specificity in the diagnosis of orbital space-occupying lesions and increases the accuracy of diagnosis.

Silencing CDR1as inhibits colorectal cancer progression through regulating microRNA-7

An increasing number of studies have demonstrated that circular RNAs (circRNAs) can regulate gene expression through interacting with microRNAs. In this study, we analyzed the expression of antisense to CDR1as in colorectal cancer (CRC). CDR1as had a higher expression in CRC tissues compared to adjacent, normal mucosa and was positively associated with tumor size, T stage, lymph node metastasis, and poor overall survival (OS). Downregulation of CDR1as suppressed CRC cell proliferation and invasion and increased microRNA-7 (miR-7) expression. Intriguingly, ectopic expression of miR-7 in CRC cells consistently inhibited proliferation and invasion, and the miR-7 inhibitor was able to rescue the function of CDR1as knockdown. Mechanistic studies demonstrated that CDR1as silencing suppressed EGFR and IGF-1R expression, which could be partially blocked by the miR-7 inhibitor. Finally, positive correlations between CDR1as expression and EGFR and IGF-1R expression were observed in CRC samples. Thus, given the importance of CDR1as in blocking miR-7 and positively regulating EGFR and IGF-1R, dysregulated CDR1as expression may play an important role in CRC progression.

Magnesium sulphate attenuate remifentanil-induced postoperative hyperalgesia via regulating tyrosine phosphorylation of the NR2B subunit of the NMDA receptor in the spinal cord

BACKGROUND

Remifentanil induced hyperalgesia (RIH) is characterized by stimulation evoked pain including allodynia and thermal hyperalgesia after remifentanil infusion. N-methyl-D-aspartate (NMDA) receptor was reported to be involved in the progress of RIH. We hypothesized that intrathecal MgSO₄ could relieve hyperalgesia after remifentanil infusion via regulating phosphorylation of NMDA receptor NR₂B subunit activity in this study.

METHODS

Thirty two rats were randomly allocated into control group, model of RIH group, RIH plus 100ug MgSO₄ group, RIH plus 300ug MgSO₄ group. Mechanical and thermal hyperalgesia were tested at -24^th h, 2^nd h, 6^th h, 24^th h, 48^th h after remifentanil infusion. Following sacrifice of rats after the last behavioral test, we performed the western blot to detect the expression of spinal phosphorylated NMDA receptor NR₂B subunit (pNR₂B) in the L₄-L₅ segments.

RESULTS

Intrathecal MgSO₄ (100, 300 μg) dose-dependently reduced thermal and mechanical hyperalgesia from 2 h to 48 h after remifentanil infusion. Remifentanil infusion remarkably stimulated the expression of pNR₂B. Nevertheless, the increased amount of pNR₂B by RIH was dose-dependently suppressed by intrathecal infusion of MgSO₄ in rats.

CONCLUSIONS

Remifentanil induced hyperalgesia/allodynia could be ameliorated by Mg-mediated blockade targeting the NR₂B subunit in NMDA receptors.

Tumour-activated liver stromal cells regulate myeloid-derived suppressor cells accumulation in the liver

Regulating mechanisms underlying hepatic myeloid-derived suppressor cell (MDSC) accumulation remain to be described. Here, we provide evidence for the involvement of tumour-activated liver stromal cells in the process of hepatic MDSCs migration and accumulation. Our data showed an elevated frequency of MDSCs in the liver of tumour-bearing mice. Moreover, tumour-activated liver stromal cells promote MDSC migration into the liver site. Further investigation indicated higher levels of cytokine and chemokine expression in liver stromal cells after exposure to the tumour-conditioned supernatant. Notably, the expression levels of proinflammatory factors, mainly including macrophage colony stimulating factor (M-CSF), transforming growth factor-β (TGF-β), monocyte chemotactic protein-1 (MCP-1) and stromal-derived factor-1 (SDF-1), increased after treatment with tumour-conditioned supernatant, and blockade of MCP-1 or SDF-1 decreased the proportion of tumour infiltrated MDSCs in mice co-transplanted with liver stromal cells and tumour cells, but not in mice with only tumour cells injection. These findings demonstrate that tumour-activated liver stromal cells produce higher levels of chemokines and cytokines, which may contribute to MDSC accumulation into the liver site in patients with liver cancer.

Simultaneous detection of 45 fusion genes in leukemia by dual-color fluorescence real-time PCR

INTRODUCTION

Detection of recurrent genetic abnormalities is of great significance for a refined diagnosis and assessment of prognosis in leukemia. Conventional nested reverse transcription PCR is labor intensive and time-consuming.

METHODS

We have developed a novel dual-color TaqMan probe-based real-time PCR method for the simultaneous screening of 45 fusion transcripts in 12 parallel reactions. The method was tested and validated with cell lines carrying known fusion transcripts and patient samples.

RESULTS

A multiplex real-time PCR method was successfully developed for rapid detection of 45 fusion genes and validated for 15 of the more commonly detected fusion genes. Intra-assay reproducibility assessed for the most frequent rearrangements ranged from 0.41% to 0.74% for the coefficient of variation (CV) of cycle threshold (Ct) and the interassay reproducibility ranged from 1.62% to 2.83% in five separate experiments. The lowest detection limit for the translocations tested ranged between 1 : 16 000 and 1 : 32 000. Validation of the method with 213 patient samples showed 100% specificity and excellent consistence with conventional nested RT-PCR.

CONCLUSION

Overall, we believe that this method is easily applicable, cost-effective, and clinically useful for a rapid screening of fusion genes in the initial diagnostic phase of leukemia. Its use can also be extended to the monitoring of minimal residual disease.

Curcumin analog EF24 induces apoptosis via ROS-dependent mitochondrial dysfunction in human colorectal cancer cells

PURPOSE

Colorectal cancer is the most commonly diagnosed malignancy with high mortality rates worldwide. Improved therapeutic strategies with minimal adverse side effects are urgently needed. In this study, the anti-tumor effects of EF24, a novel analog of the natural compound curcumin, were evaluated in colorectal cancer cells.

METHODS

The anti-tumor activity of EF24 on human colon cancer lines (HCT-116, SW-620, and HT-29) was determined by measures of cell cycle arrest, apoptosis, and mitochondrial function. The contribution of ROS in the EF24-induced anti-tumor activity was evaluated by measures of H₂O₂ and pretreatment with an ROS scavenger, NAC.

RESULTS

The findings indicated that EF24 treatment dose-dependently inhibited cell viability and caused cell cycle arrest at G2/M phase in all the tested colon cancer cell lines. Furthermore, we demonstrated that EF24 treatment induced apoptosis effectively via enhancing intracellular accumulation of ROS in both HCT-116 and SW-620 cells, but with moderate effects in HT-29 cells. We found that EF24 treatment decreased the mitochondrial membrane potential in the colon cancer cells, leading to the release of mitochondrial cytochrome c. Also, EF24 induced activation of caspases 9 and 3, causing decreased Bcl-2 protein expression and Bcl-2/Bax ratio. Pretreatment with NAC, a ROS scavenger, abrogated the EF24-induced cell death, apoptosis, cell cycle arrest, and mitochondrial dysfunction, suggesting an upstream ROS generation which was responsible for the anticancer effects of EF24.

CONCLUSIONS

Our findings support an anticancer mechanism by which EF24 enhanced ROS accumulation in colon cancer cells, thereby resulting in mitochondrial membrane collapse and activated intrinsic apoptotic signaling. Thus, EF24 could be a potential candidate for therapeutic application of colon cancer.

[Endonasal endoscopic surgery in treatment of medial recus muscle entrapment: the management and effectiveness]

Objective:To explore the indications , surgery method and effect for the treatment of medial rectus muscle entrapment with endoscopic surgery.Method: Eight medial rectus muscle entrapment patients were enrolled in this study,3 cases underwent obital medial wall fracture reposition and medial rectus muscle adhesion decomposition surgery through endonasal endoscope,and 5 cases received obital medial wall fracture reposition surgery with endoscope through nasal cavity and lacrimal caruncle conjunctival incision. Result:The diplopia disappeared and eyeball abduction function recovered in 6 cases of medial rectus muscle entrapment patients within 2 months,and 1 case with each surgery had mild diplopia and eyeball incomplete abduction left.Conclusion:Adopting endonasal endoscopic surgery or dual approaches surgery with endonasal endoscopic and transcaruncular surgery were ideal methods for medial rectus muscle entrapment diseases.Surgery with endoscope has the characteristics of clear field and less damage.The surgery should be performed whithin 3 weeks, and the entrapment of medial rectus muscle can be resoved effectively.

Thermally Assisted Nonvolatile Memory in Monolayer MoS2 Transistors

We demonstrate a novel form of thermally-assisted hysteresis in the transfer curves of monolayer MoS₂ FETs, characterized by the appearance of a large gate-voltage window and distinct current levels that differ by a factor of ∼10². The hysteresis emerges for temperatures in excess of 400 K and, from studies in which the gate-voltage sweep parameters are varied, appears to be related to charge injection into the SiO₂ gate dielectric. The thermally-assisted memory is strongly suppressed in equivalent measurements performed on bilayer transistors, suggesting that weak screening in the monolayer system plays a vital role in generating its strongly sensitive response to the charge-injection process. By exploiting the full features of the hysteretic transfer curves, programmable memory operation is demonstrated. The essential principles demonstrated here point the way to a new class of thermally assisted memories based on atomically thin two-dimensional semiconductors.

Immature Colon Carcinoma Transcript-1 (ICT1) Expression Correlates with Unfavorable Prognosis and Survival in Patients with Colorectal Cancer

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of death from cancer worldwide. Immature colon carcinoma transcript-1 (ICT1) has been reported to be correlated with lung cancer; however, whether ICT1 is a functional gene in CRC, as well as the molecular mechanism underlying ICT1 mediation of colorectal-tumor formation, remains unknown.

METHODS

The expression of ICT1 was firstly determined by using immunohistochemistry in 861 CRC specimens. The correlation of ICT1 expression with clinicopathological parameters and the survival rate was analyzed. Furthermore, we investigated the effect of ICT1 silencing on CRC cell proliferation and migration by MTT, colony formation, flow cytometry, and transwell in vitro.

RESULTS

ICT1 is highly expressed in a cohort of human CRCs, and that higher ICT1 expression may lead to reduced overall survival rate of CRC. Likewise, ICT1 silencing lowered the cell viability through cell-cycle arrest, inhibited cell migration, and induced apoptosis in CRC. We further revealed a novel mechanism in which ICT1 promoted CRC growth via the intracellular AMPK, SAPK/JNK, and PARP signaling pathways.

CONCLUSIONS

Our data showed that ICT1 could be an important target for CRC diagnosis and treatment.

[Outcomes of total deafness type of idiopathic suddendeafness in different ages]

Objective:This retrospective study was aimed to investigate the characteristics of hearing recovery in the complete deafness type of SSNHL(≥81 dBHL) in patients with different ages.Method:Clinical outcomes of 179 total deafness type of idiopathic sudden deafness were compared.Patients were divided into 5 groups according to age,they were,pediatric group(13 years or less),youthful group(14-44 years),middle-aged group(45-59 years),presenium group(60-74 years),senectitude group(75 years or higher).Patients were divided into 3 groups according to the initial degree of hearing loss: 81 dB group (81-89 dBHL),90 dB group(90- 99 dBHL),100 dB group(100 dBHL or higher).Routine comprehensive treatment including corticosteroids,the inner ear microcirculation improvement drugs,neurotrophic drugs,saturationoxygen and hyperbaric oxygen therapy,etc.was applied.Patients were treated in accordance with the age and body weight.Result:The percentage of youthful group(83/179,46.4%) was highest(P<0.05),middle-aged group(57/179,31.8%)followed(P<0.05),presenium group(26/179,14.5%)was lower(P<0.05),pediatric group(8/179,4.5%) and senectitude group(5/179,2.8%)were the lowest.No a complete recovery in either pediatric group or senectitude group.A complete recovery was rare in the other groups.Recovery rate of the different aged groups was similar(P>0.05).The percentage of 100 dB group(108/179,60.3%) was highest(P<0.05).The percentage of 81 dB group(39/179,21.8%)was similar to 90 dB group(32/179,17.9%)(P>0.05).Recovery rate was similar in 81 dB group(25/39,64.1%)and 90 dB group(18/32,56.2%)(P>0.05).Recovery rate of both 81 dB group and 90 dB group were greater than 100 dB group(24/108,22.2%)(P<0.05).The 100 dB group reduced the satisfactory recovery effects.There were no differences in the proportion of the patients with dizziness(95/179,53.1%)and without dizziness(84/179,46.9%)(P>0.05).Recovery rate of patients without dizziness(43/84,51.2%) was greater than with dizziness(24/95,25.3%)(P<0.05).The percentage of the patients without dizziness(31/39,79.5%)in 81 dB group was the highest(P<0.05),90 dB group(18/32,56.2%)followed(P<0.05).The percentage of the patients with dizziness in 100 dB group(73/108,67.6%)was highest(P<0.05).Recovery rate was similar in the patients without dizziness of 81 dB group(21/31,67.7%)and 90 dB group(11/18,61.1%)(P>0.05).Recovery rate of the above two groups was greater than that of 100 dB group(11/35,31.4%)(P<0.05).Conclusion:Recovery rate of the different aged groups was similar.The percentage of the patients with dizziness in 100 dB group was highest.Initial hearing threshold in excess of 100 dB reduced the satisfactory recovery in patients with total deafness type of SSNHL.Our results provided a good reference for other clinicians.

Fentanyl inhibits the progression of human gastric carcinoma MGC-803 cells by modulating NF-κB-dependent gene expression in vivo

Fentanyl is widely used to treat acute and chronic pain. Previous in vitro studies by the present authors demonstrated that fentanyl inhibits the progression of the MGC-803 human gastric carcinoma cell line by affecting apoptosis-related genes, including nuclear factor-kappa B (NF-κB) and phosphatase and tensin homolog. In the present study, the effects of fentanyl on NF-κB-dependent gene expression were investigated in vivo. Nude mice were inoculated with an MGC-803 cell suspension, and mice that developed subcutaneous tumors measuring >1.0×1.0 cm were selected for study. Mice were administered intraperitoneal injections of fentanyl (0.05 mg/kg, group F1; 0.1 mg/kg, group F2; 0.2 mg/kg, group F3; and 0.4 mg/kg, group F4) for 14 consecutive days. Non-fentanyl-treated mice (group C) and normal saline-treated mice (group N) served as the control groups. Tumor growth was monitored by calculating the time-shift of the growth curve. Morphological changes were also observed using microscopy. The expression of NF-κB, B-cell lymphoma-2 (Bcl-2), B-cell associated X protein (Bax), vascular endothelial growth factor-A (VEGF-A) and matrix metalloproteinase-9 (MMP-9) in the subcutaneous tumor tissue was also analyzed by reverse transcription-polymerase chain reaction and western blot analysis, and confirmed using immunohistochemistry. The relative tumor volumes of groups F1, F2, F3 and F4 were significantly reduced compared with groups C and N. Furthermore, subcutaneous tumor cells exhibited nuclear swelling, chromatin condensation, reduced chromatin and nuclear fragmentation in the F1, F2, F3 and F4 groups. The number of NF-κB⁺, Bcl-2⁺, VEGF-A⁺ and MMP-9⁺ subcutaneous tumor cells was reduced, whereas the number of Bax⁺ cells was increased in the F1, F2, F3 and F4 groups. Additionally, in these groups, tumor expression of NF-κB, Bcl-2, VEGF-A and MMP-9 transcripts and proteins was downregulated, while Bax messenger RNA and protein expression levels were upregulated. The results revealed that fentanyl inhibits the growth of subcutaneous human gastric carcinoma tumors in mice. Therefore, it could be hypothesized that this antineoplastic activity may result from the inhibition of NF-κB activation, suppression of downstream VEGF-A and MMP-9 expression, and normalization of the pro-apoptotic Bax/Bcl-2 ratio.

Tristetraprolin: a novel mediator of the anticancer properties of resveratrol

Resveratrol is a natural compound that exhibits anticancer properties. Previous studies have proved that it can inhibit the proliferation of breast cancer cell lines and upregulate some cytokines such as cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF). The initiation and progression of cancer are associated with the abnormal expression of multiple cytokines. Tristetraprolin (TTP), an mRNA-binding protein, is one of the key proteins that participate in regulating cytokine expression. Two different proliferation assays on MCF-7 cells showed that the cell proliferation rate significantly reduced following treatment with resveratrol. Most importantly, we found that resveratrol promoted TTP expression at both the mRNA and protein level in a dose- and time-dependent manner. In addition, the expression of COX-2 and VEGF were significantly suppressed by resveratrol while that of inducible nitric oxide synthase (iNOS) was upregulated. Lastly, the effects of resveratrol on both MCF-7 proliferation and expression of COX-2, VEGF, and iNOS were significantly inhibited by TTP knockdown, indicating that TTP mediates the anticancer properties of resveratrol. In summary, we conclude that resveratrol inhibits the proliferation of MCF-7 cells by TTP upregulation, which is associated with downregulation of COX-2 and VEGF and upregulation of iNOS.

Simultaneous Determination of Ticagrelor and Its Metabolites in Human Plasma and Urine Using Liquid Chromatography-Tandem Mass Spectrometry

We have developed and validated a rapid, selective and sensitive method using high-performance liquid chromatography-tandem mass spectrometry (MS) for the quantification of ticagrelor and all of its as-yet-identified metabolites in human plasma and urine. For the analysis of ticagrelor, its metabolites and the internal standard (IS) plasma samples were processed by liquid-liquid extraction using ethyl acetate and urine was processed by protein precipitation. Separations were performed on an Ultimate XB-C18 column (2.1 mm × 150 mm, 3 μm), using aqueous ammonium acetate (0.025 mM)/acetonitrile (35 : 65, v:v) as the mobile phase. Ticagrelor and all 11 metabolites were eluted within 4.5 min. Quantification was performed using electrospray ionization, operating in negative ion mode. The ticagrelor and metabolite M8 (AR-C124910XX) responses were optimized at the m/z 521.2 → 361.2 and m/z 477.2 → 361.1 transitions, respectively. The assay was validated over the linear range of 0.5-2,000 ng/mL for ticagrelor and M8. The intra- and inter-assay precisions were ≤14.6% for ticagrelor and ≤14.7% for M8, respectively. The matrix effects of plasma and urine were in the range of 98.3-110.7% for ticagrelor and 102.1-112.3% for M8. The relative quantification of other metabolites was performed by assessing the ratio of metabolite to IS peaks. The newly developed method was successfully used in a pharmacokinetic study characterizing ticagrelor metabolism in human volunteers.

Ribosomal protein S15A promotes malignant transformation and predicts poor outcome in colorectal cancer through misregulation of p53 signaling pathway

Ribosomal protein S15A (RPS15A), which has been identified as a highly conserved 40S ribosomal protein, is essential for cell survival and proliferation. The present study evaluated the functional role of RPS15A in colorectal cancer (CRC), and our investigation found that RPS15A was highly expressed in a cohort of human CRC. High RPS15A expression was associated with older age (P=0.035), not receiving preoperative neoadjuvant treatment (P=0.048), higher primary pN stage (P=0.007) and slightly more synchronous distant metastases (P=0.058). The Cox univariate and multivariate hazard regression analysis revealed that higher expression of RPS15A led to a reduction of overall survival rate in CRC, indicating that enhanced RPS15A expression functions as an independent risk factor for the prognosis of CRC patients (P<0.001). Cell based analysis showed that RPS15A was widely expressed in human CRC cell lines. Knockdown of RPS15A significantly suppressed cell proliferation and colony formation in HCT116 and DLD-1 cells, and induced cell cycle arrest at G0/G1 phase. Genechip analysis suggested that knockdown of RPS15A might affect the p53 signaling pathway. Further study indicated that RPS15A knockdown upregulated p53 and p21 expression whereas downregulated CDK1 expression. In summary, the present study identified RPS15A as a novel univariate prognostic factor predicting a poor outcome in CRC patients. The RPS15A overexpression induced by malignant transformation of CRC might function through the p53 signaling pathway.

"Freeing" Graphene from Its Substrate: Observing Intrinsic Velocity Saturation with Rapid Electrical Pulsing

Rapid (nanosecond-scale) electrical pulsing is used to study drift-velocity saturation in graphene field-effect devices. In these experiments, high-field pulses are utilized to drive graphene's carriers on time scales much faster than that on which energy loss to the underlying substrate can occur, thereby allowing the observation of the highest saturation velocities reported to date. In a dramatic departure from the behavior exhibited by conventional metals and semiconductors, as the electron or hole density is reduced toward the charge-neutrality point, the drift velocity is found to reach values comparable to the Fermi velocity itself. Corresponding current densities are as large as 10(9) A/cm(2), similar to the values reported for carbon nanotubes and for graphene-on-diamond transistors. In essence, our approach of rapid pulsing allows us to "free" graphene from the deleterious influence of its substrate, revealing a pathway to achieve the superior electrical performance promised by this material. The usefulness of this approach is not merely limited to graphene but should extend also to a broad variety of two-dimensional semiconductors.

Block copolymer synthesis by controlled/living radical polymerisation in heterogeneous systems

We review the range of CLRP-controlled syntheses of block copolymer particles in dispersed systems, which are being exploited to create new opportunities for the design of nanostructured soft materials.