MiR-101 promotes nasopharyngeal carcinoma cell apoptosis through inhibiting Ras/Raf/MEK/ERK signaling pathway.

The article "MiR-101 promotes nasopharyngeal carcinoma cell apoptosis through inhibiting Ras/Raf/MEK/ERK signaling pathway, by R.-S. Wu, E.-H. Qiu, J.-J. Zhu, J.-R. Wang, H.-L. Lin, published in Eur Rev Med Pharmacol Sci 2018; 22(1): 150-157-DOI: 10.26355/eurrev_201801_14112-PMID: 29364482" has been withdrawn from the authors. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/14112.

MiR-101 promotes nasopharyngeal carcinoma cell apoptosis through inhibiting Ras/Raf/MEK/ERK signaling pathway.

OBJECTIVE: Extra-cellular signal regulated kinase (ERK)/mitogen activated protein kinase (MAPK) signaling pathway is widely involved in cell proliferation and apoptosis. MAPK kinase 1 (MEK1) is the upstream protein kinase of ERK that can activate ERK/MAPK signaling pathway. microRNA-101 (MiR-101) down-regulation is found to be associated with nasopharyngeal carcinoma (NPC) pathogenesis. Bioinformatics analysis shows the complementary targeted relationship between miR-101 and the 3'-UTR of MEK1 mRNA. This study explores the role of miR-101 in regulating MEK1 expression, ERK/MAPK signaling pathway activation, and NPC pathogenesis. MATERIALS AND METHODS: Dual luciferase assay confirmed the targeted relationship between miR-101 and MEK1. MiR-101 and MEK1 expressions were compared in inflammatory nasopharynx tissue and NPC tissue. MiR-101, MEK1, phosphorylated ERK 1/2 (p-ERK1/2), survivin expressions in NP69, CNE-1, HONE1, and C666-2 cell lines were detected. NPC cell line C666-1 was cultured in vitro and divided into four groups, including miR-NC, miR-101, si-NC and si-MEK1. Cell apoptosis was determined by flow cytometry. Cell proliferation was evaluated by EdU staining. RESULTS: MiR-101 targeted inhibited MEK1 expression. MiR-101 was significantly down-regulated, while MEK1 was significantly elevated in NPC tissue compared with inflammatory nasopharynx tissue. MiR-101 was markedly declined, whereas MEK1, p-ERK1/2, and survivin were apparently increased in CNE-1, HONE1, and C666-1 cells compared with NP69 cells. MiR-101 mimic and/or si-MEK1 transfection significantly reduced MEK1, p-ERK1/2, and survivin levels, attenuated cell proliferation, and enhanced cell apoptosis. CONCLUSIONS: Down-regulation of miR-101 was related to NPC pathogenesis. MiR-101 elevation suppressed NPC cell proliferation and promoted apoptosis through targeted inhibiting MEK1 expression to alleviate ERK/MAPK signaling pathway and survivin expression.

Screening of bacteria for self-healing of concrete cracks and optimization of the microbial calcium precipitation process.

A novel high-throughput strategy was developed to determine the calcium precipitation activity (CPA) of mineralization bacteria used for self-healing of concrete cracks. A bacterial strain designated as H4 with the highest CPA of 94.8 % was screened and identified as a Bacillus species based on 16S rDNA sequence and phylogenetic tree analysis. Furthermore, the effects of certain influential factors on the microbial calcium precipitation process of H4 were evaluated. The results showed that lactate and nitrate are the best carbon and nitrogen sources, with optimal concentrations of approximately 25 and 18 mM, respectively. The H4 strain is able to maintain a high CPA in the pH range of 9.5-11.0, and a suitable initial spore concentration is 4.0 × 10(7) spores/ml. Moreover, an ambient Ca(2+) concentration greater than 60 mM resulted in a serious adverse impact not only on the CPA but also on the growth of H4, suggesting that the maintenance of the Ca(2+) concentration at a low level is necessary for microbial self-healing of concrete cracks.

Toxicity of metal oxide nanoparticles: mechanisms, characterization, and avoiding experimental artefacts.

Metal oxide nanomaterials are widely used in practical applications and represent a class of nanomaterials with the highest global annual production. Many of those, such as TiO2 and ZnO, are generally considered non-toxic due to the lack of toxicity of the bulk material. However, these materials typically exhibit toxicity to bacteria and fungi, and there have been emerging concerns about their ecotoxicity effects. The understanding of the toxicity mechanisms is incomplete, with different studies often reporting contradictory results. The relationship between the material properties and toxicity appears to be complex and diifficult to understand, which is partly due to incomplete characterization of the nanomaterial, and possibly due to experimental artefacts in the characterization of the nanomaterial and/or its interactions with living organisms. This review discusses the comprehensive characterization of metal oxide nanomaterials and the mechanisms of their toxicity.

Citosol (thiamylal sodium) triggers apoptosis and affects gene expressions of murine leukemia RAW 264.7 cells.

Citosol (thiamylal sodium) is one of generally used anesthetic-sedative agents for clinical patients, and it has not been reported to show induction of cytotoxic effects in cancer cells, especially in mice leukemia RAW 264.7 cells in vitro. In the present study, we investigated the cytotoxic effects of citosol on mice leukemic RAW 264.7 cells, including the effects on protein and gene expression levels which are determined by Western blotting and DNA microarray methods, respectively. Results indicated that citosol induced cell morphological changes, cytotoxic effect, and induction of apoptosis in RAW 264.7 cells. Western blotting analysis demonstrated that citosol promoted the levels of Fas, cytochrome c, caspase 9 and 3 active form and Bax levels, but it suppressed Bcl-xl protein level that may lead to apoptotic death in RAW 264.7 cells. Furthermore, DNA microarray assay indicated that citosol significantly promoted the expression of 5 genes (Gm4884, Gm10883, Lce1c, Lrg1, and LOC100045878) and significantly inhibited the expression of 24 genes (Gm10679, Zfp617, LOC621831, Gm5929, Snord116, Gm3994, LOC380994, Gm5592, LOC380994, LOC280487, Gm4638, Tex24, A530064D06Rik, BC094916, EG668725, Gm189, Hist2h3c2, Gm8020, Snord115, Gm3079, Olfr198, Tdh, Snord115, and Olfr1249). Based on these observations, citosol induced cell apoptosis and influenced gene expression in mice leukemia RAW 264.7 cells in vitro.

Application of artificial mussels (AMs) under South African marine conditions: a validation study.

Over the last three decades there has been a significant decline in the number of marine pollution monitoring-related studies in South Africa. Thus, the current study was conducted to assess the current state of metal contamination within the South African marine environment through the validation of the artificial mussel (AM). Indigenous reference mussels (Perna perna) were deployed alongside the passive device within the South African marine environment for a 6 week exposure period. Analysis of metal uptake (Cd, Cr, Cu, Pb and Zn) was determined by filtration and elution of the AM chelex resins, microwave digestion of the transplanted mussels, and determination of their metal concentrations by ICP-MS and ICP-OES analysis. Uptake patterns between the AM and transplanted mussels showed significant temporal and spatial correlation for the majority of the elements analysed. While the AM provided relevant and complementary information on the dissolved metal concentrations, limitations were also observed.

A whole life cycle assessment on effects of waterborne PBDEs on gene expression profile along the brain-pituitary-gonad axis and in the liver of zebrafish.

Polybrominated diphenyl ethers (PBDEs) are now found ubiquitously in the aquatic environment and biota, and there is a growing concern that PBDEs may disrupt endocrine systems, leading to reproductive impairments of aquatic animals. In our study, zebrafish (Danio rerio) were exposed to the 5 ng/L, 1 µg/L and 50 µg/L of DE-71 for the duration of the whole life cycle (120 days, from eggs to adults). The expression of selected genes along the brain-pituitary-gonadal (BPG) axis and liver, and the levels of plasma sex hormones were examined. In male fish, up-regulation of GnRH in brain, FSHß and LHß in pituitary, FSH-receptor, LH-receptor, and CYP19a in testis was clearly evident, while down-regulation of CYP11a and 3ß-HSD was found in testis. In female fish, a 2.4-fold up-regulation of 3ß-HSD was found in ovary upon exposure to 50 µg/L of DE-71. GnRH in brain, FSHß and LHß in pituitary were also up-regulated, while ERß, TH and TPH in brain and GnRH-receptor in pituitary were significantly down-regulated. Hepatic ERα, AR and VTG in males were all down-regulated, while hepatic ERα and AR in female were up-regulated. Serum estradiol (E2) was reduced in both male and female upon exposure to DE-71, while significant increases in serum testosterone (T) and 11-keto-testosterone (11-KT) were only found in male but not female fish. The ratio of T/E2 as well as the ratio of 11-KT/E2 in male fish increased in a dose-dependent manner upon exposure to DE-71. Our overall results showed that whole life exposure of DE-71 altered the expression of regulatory genes and receptors at all three levels of the BPG axis in zebrafish, and the responses are sex dependent. The observed disruption of GnRH and GtHs can be further related to the subsequent disruption in both levels and balance sex steroid hormones.

Brown mussels (Perna perna) and semi-permeable membrane devices (SPMDs) as indicators of organic pollutants in the South African marine environment.

A distinct lack of historical and current data on the status of organic pollutant contaminants within the South African marine environment is evident. This has highlighted the need for more current organic pollutant assessments. Reference mussels and SPMDs were transplanted at five South African harbour sites to assess organic bioaccumulation in brown mussels (Perna perna) and semi-permeable membrane devices (SPMDs). Spatial patterns of PAH and PCB contaminants were determined by GC-MS and GC-ECD after appropriate sample preparation. Significant (p<0.05) spatial differences were observed between the sites. Results indicate no correlations between the passive device and the transplanted mussels; however the SPMDs provided complementary information on the presence of dioxin-like PCBs within the environment not detected by the mussel. The results indicate that information provided by both the mussels and SPMDs allow for a more in depth scrutiny of environmental conditions as a result of anthropogenic influence.

Open-access colonoscopy: outcomes of referrals from the emergency department.

AIM: The study investigated the diagnostic outcome of colonoscopy referrals from the emergency department (ED) via an open-access system. METHOD: A retrospective cohort study over two years was performed on all patients under 65 years referred for open-access colonoscopy by the ED in a hospital with an annual ED attendance of 140,000. Patient characteristics and presenting symptoms were retrieved. Waiting times from presentation to colonoscopy were recorded. RESULTS: Over a 2-year period, 266 patients were referred, of whom 37 defaulted, leaving 229 patients who had a colonoscopy. The mean age was 48.3 ± 11.3 (SD) and the female/male ratio was 229/125. The most frequent presenting symptoms included: rectal bleeding (n = 142, 62%), change of bowel habit (n = 47, 20.5%) and abdominal pain (n = 40, 17.5%). The median waiting time from presentation to colonoscopy was 17 (range 1-69) days. A positive colonoscopic finding was recorded in 45.4%, including colorectal cancer in 12 (5.2%). CONCLUSION: The rate of a positive diagnoses from the ED-based colonoscopy referral service was comparable to that of the general Hong Kong population. This approach may help to reduce the waiting time for colonoscopy in a specialist colorectal clinic.

Power analysis for biomarkers in mussels for use in coastal pollution monitoring.

Data from literature on neutral red retention time (NRRT) in lysosomes, micronucleus (MN) frequency and condition index (CI) in mussel Mytilus, especially Mytilus edulis and Mytilus galloprovincialis, were re-analyzed to ascertain their statistical power in detecting a minimum 20% spatial/temporal change in field studies. Results showed that CI largely displayed higher statistical power (>90%) than lysosomal NRRT and MN frequency (<50%), suggesting that data from the latter two biomarkers may lead to erroneous conclusions if sample size is inadequate. Samples of green-lipped mussel Perna viridis were also analyzed in Hong Kong. To achieve statistically valid power, the optimal sample sizes for monitoring lysosomal NRRT, MN frequency, CI and gonosomatic index (GSI) were determined as >or=34, >or=90, >or=16 and >or=29, respectively. Natural variability of lysosomal NRRT and MN frequency was significantly greater than CI and/or GSI in mussels, rejecting the general belief in the greater variability of higher-tiered hierarchical biomarkers.

In situ hybridization to detect spatial gene expression in medaka.

A whole-animal tissue section in situ hybridization (ISH) system with radio-labeled probes was developed to detect differential gene expression among tissues of the small, oviparous teleost fish, Japanese medaka (Oryzias latipes). Because of its tissue- and gender-specific expression, gonadal aromatase (CYP19a) was selected as a model gene to demonstrate the potential of the system. The ISH system was validated with a 7d exposure to the model aromatase inhibitor, fadrozole. Fadrozole did not affect the magnitude of gene expression in testes, but significantly up-regulated CYP19a gene expression in ovaries. These results were confirmed with quantitative real-time-polymerase chain reaction (RT-PCR). Histological evaluation revealed that females exposed to 100microg/L fadrozole lacked mature oocytes. Male gonadal morphology was normal in all treatments. The ISH method developed in this study allowed tissue-specific resolution of gene expression in a whole animal model, as well as the ability to analyze cellular morphological detail in the same organism.

Persistent dizziness and nausea in patients receiving postoperative epidural pain control after living donor liver transplantation: case reports.

Dizziness and nausea are frequent problems among patients receiving patient-controlled epidural analgesia (PCEA) after major surgery. It is important to consider the various etiologies that might cause these adverse events, especially among patients who have undergone massive hepatic resection for living donor liver transplantation (LDLT). We have described 2 LDLT cases with persistent dizziness and nausea postoperatively despite several adjustments in PCEA management. Their symptoms were quickly relieved after suspension of PCEA medication. Our 2 cases of LDLT represented a unique setting for this type of complication.

Artificial vascular graft for inferior vena cava reconstruction in living donor liver transplantation: a case report.

Artificial grafts are not recommended because of the high incidence of thrombogenic effects. However, in some situations, such as emergency or when no vascular bank is available, an artificial graft must be used. We present a case in which a polytetrafluoroethyline graft was used as a conduit to reconstruct the retrohepatic vena cava severed during living donor liver transplantation (LDLT). A 48-year-old woman had end-stage primary biliary cirrhosis for 5 years received a right lobe liver graft from her son. The retrohepatic vena cava was divided and ligated in several sequences. The upper end of the severed retrohepatic vena cava retracted into the liver parenchyma. The lower end of the severed vena cava was distended, with multiple stitches. A 16-mm artificial graft was used as a conduit to replace the inferin vena cava for outflow reconstruction. The patient tolerated the complicated procedure well. No anticoagulant was used throughout the entire course. The patient has been well with excellent liver function after follow-up for more than 5 years. Magnetic resonance imaging and Doppler ultrasonographic studies showed good patency of the cava with no evidence of thrombosis. We suggest use of an artificial graft in living donor liver transplantation, in particular in urgent situations when autologous or allogeneic vessels are not available.

Influences of ammonia-nitrogen and dissolved oxygen on lysosomal integrity in green-lipped mussel Perna viridis: laboratory evaluation and field validation in Victoria Harbour, Hong Kong.

Lysosomal integrity in mussels has been applied as a biomarker to detect the pollution of trace organics and metals in the natural environments. However, few studies have examined the effects of water quality on the response of lysosomal integrity, in particular total ammonia-nitrogen (TAN) and dissolved oxygen (DO). This study demonstrated that high level of TAN (2.0mg/l) and low DO (2.5mg O(2)/l) could significantly reduce the lysosomal integrity in green-lipped mussel Perna viridis, respectively by 33% and 38%, whereas the mussel lysosomal integrity decreased by 70% in the combined treatment of TAN and low DO under laboratory conditions after one week. The mussel lysosomal integrity of all treatment groups could return to the control level after a three week recovery period. In the field validation in Victoria Harbour, Hong Kong during an one-year study period, lysosomal integrity in P. viridis identified the cleanest site east to the harbour, where the lowest TAN and highest DO concentrations were found. While lysosomal integrity in mussels seemed not affected by seasonal changes, approximately 40% of the variation of this biomarker could be attributable to the changes in TAN and DO in seawater. In conclusion, the response of the mussel lysosomal integrity can be confounded by both TAN and DO prevailing in the natural environments and thus caution must be exercised in relating the observed changes in lysosomal integrity to any specific pollutant in coastal water quality monitoring studies.

Induction, adaptation and recovery of lysosomal integrity in green-lipped mussel Perna viridis.

Biomarkers are generally applied to detect pollution in environmental monitoring. Such biological responses should accurately reflect the stress over time in a quantitative manner. As such, the initial and maximum responses induced by stress, as well as adaptation and recovery of these biomarkers, need to be fully understood or else erroneous false-negative or false-positive may be arrived. However, most of the biomarker studies only provided information on initially induced responses under different concentrations of toxicants, while biological adaptation and recovery were poorly known. In this study, the time required for induction, adaptation and recovery of lysosomal integrity in green-lipped mussel Perna viridis upon exposure to benzo[a]pyrene was investigated over a period of 62 days. Maximum induction occurred on day 6 when lysosomal integrity was significantly reduced by 51%, and no further change or adaptation was detected thereafter. When mussels were depurated in clean seawater after 18 days of exposure to benzo[a]pyrene, a gradual recovery was observed, with lysosomal integrity returning to its background level and showing a complete recovery after 20 days of depuration. Lysosomal integrity was significantly correlated with the body burden concentrations of benzo[a]pyrene and condition index of the mussels. The relatively fast induction (6 days) and recovery (20 days) without apparent adaptation suggested that lysosomal integrity in P. viridis can serve as a good biomarker in biomonitoring, as its response is not likely to generate both false-negative and false-positive results.

Development of a marine fish model for studying in vivo molecular responses in ecotoxicology.

A protocol for fixation and processing of whole adult marine medaka (Oryzias melastigma) was developed in parallel with in situ hybridization (ISH) and immunohistochemistry (IHC) for molecular analysis of in vivo gene and protein responses in fish. Over 200 serial sagittal sections (5microm) can be produced from a single adult medaka to facilitate simultaneous localization and quantification of gene-specific mRNAs and proteins in different tissues and subcellular compartments of a single fish. Stereological analysis (as measured by volume density, V(v)) was used to quantify ISH and IHC signals on tissue sections. Using the telomerase reverse transcriptase (omTERT) gene, omTERT and proliferating cell nuclear antigen (PCNA) proteins as examples, we demonstrated that it is possible to localize, quantify and correlate their tissue expression profiles in a whole fish system. Using chronic hypoxia (1.8+/-0.2 mgO(2)L(-1) for 3 months) as an environmental stressor, we were able to identify significant alterations in levels of omTERT mRNA, omTERT protein, PCNA (cell proliferation marker) and TUNEL (apoptosis) in livers of hypoxic O. melastigma (p<0.05). Overall, the results suggest that O. melastigma can serve as a model marine fish for assessing multiple in vivo molecular responses to stresses in the marine environment.

Spatio-temporal changes of marine macrobenthic community in sub-tropical waters upon recovery from eutrophication. II. Life-history traits and feeding guilds of polychaete community.

A two-year study was conducted in the vicinity of a harbour in sub-tropical Hong Kong, to examine the progress of recovery of macrobenthic community, based on analyses of both life-history traits and trophic guilds of polychaetes, upon cessation of organic pollution caused by sewage discharge. Seventy seven out of 83 species collected were classified under four ecological groups based on the life-history traits and sensitivity to organic gradients. The mean ATZI marine biotic index (AMBI) derived from these ecological groups showed spatial difference among the five sampling locations. In particular, the presence of different percentages of polychaete species from Groups III (unbalanced community) and IV (polluted community) suggested the presence of pollution stress in certain degree at all sampling locations. However, no significant temporal changes were noted over the study period. From all polychaete species identified, they were classified into 13 feeding guilds. The mean diversity of these feeding guilds at most of the sampling locations was significantly higher than that at one of the inside-harbour locations. The composition of feeding guilds was also significantly different spatially. At one of the inside-harbour locations, the dominant feeding guilds were motile/discretely motile surface deposit feeders with tentaculates or unarmed pharynx, and motile omnivores with jawed pharynx in the first year of study, but were replaced by motile, jawed carnivores in the second year of study. The increased proportion of carnivores over the study period can be seen as a sign of recovery in the community structure since abundance of predators is commonly higher in habitats with better environmental quality. The implications of using life-history traits and feeding guild analyses for benthic community are discussed.