Improved risk stratification of nasopharyngeal cancer by targeted sequencing of Epstein-Barr virus DNA in post-treatment plasma.

BACKGROUND: Quantitative measurement of plasma Epstein-Barr virus (EBV) DNA by real-time PCR at the end of primary treatment is a robust prognostic marker for nasopharyngeal carcinoma (NPC) patients. However, up to 40% of patients who would later develop disease recurrence had undetectable post-treatment plasma EBV DNA. Targeted sequencing for the entire EBV genome potentially allows a more comprehensive and unbiased detection of plasma EBV DNA and enables the use of other parameters such as fragment size as biomarkers. Hence, we explored if plasma EBV DNA sequencing might allow more accurate prognostication of NPC patients. PATIENTS AND METHODS: Plasma samples collected from 769 patients with stage IIB-IVB NPC at 6-8 weeks after radiotherapy were analysed using targeted sequencing for EBV DNA. RESULTS: The sensitivities of the PCR-based analysis, at a cut-off of any detectable levels of plasma EBV DNA, for prediction of local and distant recurrences were 42.3% and 85.3%, respectively. The sequencing-based analysis (involving quantitation and size profiling) achieved better performance for both local and distant recurrences than PCR. Using a cut-off of the proportion of plasma EBV DNA deduced by sequencing at 0.01%, the sensitivities of the sequencing-based analysis for local and distant recurrences were 88.5% and 97.1%, with the resultant negative predictive values of 99.1% and 99.4%, respectively. Among patients with undetectable EBV DNA on quantitative PCR, sequencing could further define a subgroup that enjoyed superior survival outcomes based on the proportion of plasma EBV DNA, with a 5-year progression-free survival (PFS) approaching 90%. On multivariate analysis, sequencing-based quantitative level of plasma EBV DNA was the independent prognostic factor with the highest hazard ratio for prediction of overall survival and PFS. CONCLUSION: NPC prognostication using post-treatment plasma EBV DNA could be enhanced through sequencing.

[Clinical analysis of 15 cases with myeloperoxidase antineutrophil cytoplasmic antibody associated hypertrophic pachymeningitis].

To study the clinical features of myeloperoxidase(MPO) antineutrophil cytoplasmic antibody (ANCA) associated hypertrophic pachymeningitis (HP). Clinical data of 15 cases diagnosed with MPO-ANCA vasculitis complicated with HP were retrospectively analyzed. Nine cases were males and the other 6 were females, with an average age of (58±8) years. All cases presented with chronic headache. Contrast-enhanced magnetic resonance imaging (MRI) scan showed local or diffused thickening of cerebral and/or spinal dura matter while brain parenchyma were normal. Nine cases developed multiple cranial nerve paralysis, with trigeminal nerve and auditory nerve involved most commonly. The main clinical manifestations were facial pain, hearing loss and tinnitus. Two cases were complicated with hypertrophic spinal pachymeningitis (HSP) and 4 cases were complicated with pulmonary diseases. Positive serum perinuclear pattern ANCA (pANCA) and MPO could be found in all cases, positive serum IgG4 was seen in two patients. erythrocyte sedimentation rate(ESR;25-116 mm/1h) and C-reactive protein (CRP;29.02-146.00 mg/L) were both elevated in 14 cases. Nine cases had elevated intracranial pressure[180-235 mmH2O (1 mmH2O=0.009 8 kPa)] and abnormal protein level (457.6-3710.0 mg/L) in cerebrospinal fluid. Six cases were treated with glucocorticoids (prednisone 20-60 mg/d) and 9 cased with glucocorticoids and immunosuppressants (methotrexate 15 mg/week or cyclophosphamide 100 mg/d po). All patients achieved remission. MPO-ANCA associated HP is a special type of central nervous system involvement in ANCA associated vasculitis (AAV). It rarely involves the lung or kidney. Steroids and immunosuppressive agents are effective. In HP with unknown underlying diseases, it is suggested to screen ANCA and IgG4 tests for AAV or IgG4-related disease.

[Clinical characteristics of patients with antisynthetase syndrome and positive anti-Ro52 antibody].

To analyze the clinical characteristics of patients with antisynthetase syndrome (ASS) and positive anti-Ro52 antibody. The clinical data of 203 ASS patients admitted to the First Affiliated Hospital of Zhengzhou University from 2017 to 2020 were analyzed retrospectively. Demographics, clinical manifestations, laboratory results, treatment and outcome were collected including data of 18 patients with rapidly progressive interstitial lung disease (RP-ILD). In total, the majority were women (148,72.9%). The average onset age was (51.9±13.3) years. There were 163 (80.3%) patients with positive anti-Ro52 antibody. The positivity in women (77.3% vs. 55.0%, P=0.004) was higher, and the median time from disease onset to diagnosis [4.5 (2.0, 24.0) months vs. 2.0 (1.0, 12.0) months, P=0.024] was longer in patients with positive anti-Ro52 antibody than those negative. Compared with negative patients, patients with positive anti-Ro52 antibody had a higher incidence of interstitial lung disease (ILD) (96.9% vs. 65.0%, P<0.001), arthritis (33.7% vs. 17.5%, P=0.046), and arthralgia (39.3% vs. 20.0%, P=0.022). Higher rate of positve antinuclear antibody (ANA) (85.3% vs. 55.0%, P<0.001), lower rate of positive anti-Jo-1 antibody (32.5% vs. 50.0%, P=0.039), lower albumin level [(34.6±5.2) g/L vs. (37.3±4.7) g/L,P=0.004] and lower lymphocyte counts [(1.4±0.8) ×109/L vs. (1.8±0.8) ×109/L, P=0.014] were more common in patients with positive anti-Ro52 antibody. The presence of anti-Ro52 antibody is associated with a particular phenotype of ASS, leading to common ILD, involvement of joints, high ANA positivity, low albumin and low lymphocyte counts.

[The role of Artificial intelligent-based FFRCT in assessing the hemodynamic relevance of deep myocardial bridge of the left anterior descending coronary artery].

Objective: To investigate the role of artificial intelligence-based coronary CT blood flow reserve score (FFRCT) in assessing hemodynamic relevance in patients with deep myocardial bridge (MB) of the left anterior descending coronary artery. Methods: A total of 113 patients diagnosed with deep MB of the left anterior descending coronary artery by coronary CT angiography (CCTA) at the Department of Radiology of Tongji Hospital Affiliated to Tongji University from January 2017 to December 2019 were retrospectively analyzed. The location, length, depth, and degree of systolic compression of the MB were measured. The artificial intelligence-based coronary FFRCT software was employed to calculate the FFRCT value of the deep MB of the left anterior descending coronary artery. With the boundary of 0.80, all patients were divided into FFRCT normal group (FFRCT>0.80) and FFRCT abnormal group (FFRCT≤0.80), and the relationship between FFRCT abnormality and the location, length, depth, and degree of systolic stenosis of the deep MB of the left anterior descending branch was analyzed. The effectiveness of the receiver operating characteristic (ROC) curve in predicting FFRCT abnormalities was measured by using ROC curve to analyze the length, depth, and degree of systolic stenosis of MB. Results: There were no significant differences in age, gender and high-risk factors between FFRCT normal group (n=79) and FFRCT abnormal group (n=34) (P>0.05). In terms of clinical symptoms, unstable angina, asymptomatic myocardial ischemia, stable angina in the FFRCT normal group were 15.2%, 41.8%, 32.9%,respectively, while 32.4%, 23.5%, 35.3% in the FFRCT abnormal group,respectively. Except for unstable angina (χ²=4.32,P=0.038), there were no significant differences in asymptomatic myocardial ischemia and stable angina between the two groups (χ²=3.42, 0.06, P>0.05). The length of deep MB was about (36±5) mm in the FFRCT normal group and (44±5) mm in the FFRCT abnormal group, respectively. The difference between the two groups was statistically significant (t=-7.703, P<0.001). The ROC curve showed that the optimal critical value of the length of the deep MB was 39.7 mm, the area under the curve was 0.88 (95%CI:0.81-0.95, P<0.001), and the accuracy rate of diagnosing FFRCT ≤0.80 was 82.3%. Conclusion: FFRCT value is of great value in the evaluation of hemodynamics in patients with deep myocardial bridge of left anterior descending coronary artery, and the length of deep myocardial bridge is an important factor affecting FFRCT value.

[Analysis of pancreatic segmentation algorithm based on deep learning to improve pancreatic critical region segmentation ability on dual-phase CT].

Objective: To investigate the segmentation effects of the deep learning method on CT in the arterial phase and venous phase respectively by using subjective and objective evaluation system, and to investigate the factors that affect the difference between arterial phase and venous phase pancreas segmentation and the related factors affecting the venous pancreas segmentation. Method: A total of 218 cases of pancreatic CT scan data in the Department of Radiology of Peking Union Medical College Hospital from January to November 2019 were retrospectively collected. Each case contained images of arterial and venous phases, and the data were randomly divided into training set (139 cases), validation set (20 cases) and test set (59 cases) according to the ratio of the training and verification set to the test set of 7∶3. The two-stage global local progressive fusion network was trained on the training set, the model parameters of the optimal segmentation effect were found on the validation set, and the test set was predicted and the results were evaluated subjectively and objectively. The Likert 5-point scale was used for subjective evaluation based on the critical regions between pancreas and peripheral organs, while the Dice similarity coefficient (DSC) was used for objective evaluation. The paired t test or Wilcoxon paired rank test was used to compare the differences of subjective and objective scores of the arterial phase and venous phase. Results: For the critical regions of the pancreas at the duodenum, duodenal jejunal flexure, left adrenal gland, portal vein, superior mesenteric vein, splenic artery and splenic vein, the median number of subjective scores in arterial phase were 4(4, 5), 5(4, 5), 5(4, 5), 4(4, 5), 5(4, 5), 5(5, 5) and 4(3, 5)points respectively, the median number(first quartile, third quartile) of subjective scores in venous phase were 4(4, 4), 5(4, 5), 5(4, 5), 5(4, 5), 5(5, 5), 4(3, 4) and 5(5, 5) points respectively,there were statistically significant differences of the median number(first quartile, third quartile) of the subjective scores between the arterial and venous phase for the critical regions of the pancreas at the organs described above (all P<0.05). DSC in the venous phase was slightly higher than that in the arterial phase and the difference was not statistically significant (DSC: 0.932 vs 0.921, P=0.952). Subjective scores in venous phase of the pancreas and duodenal jejunum, stomach, and left adrenal gland with fat gaps were 4.64,4.68 and 4.63 points respectively, and those of the group without fat gaps were 4.56,4.62 and 4.56 points respectively, there were statistically significant differences of the subjective scores in venous phase of the groups with fat gaps or not between the pancreas and the organs described above (t=2.147, 2.112, 2.277, all P<0.05). Except the spleen, the density differences between the critical regions of the pancreas and other surrounding organs were statistically significant in arterial phase and venous phase segmentation (all P<0.05). Conclusion: Dual-phase CT was used to construct a deep learning automatic pancreas segmentation model, and the segmentation effect was evaluated subjectively and objectively. Subjective evaluation was helpful to improve the ability to segment the critical regions of the pancreas in the future.

[The characteristics of recent HIV-1 infection and associated factors in Tianjin].

The newly reported HIV infected cases was collected, and HIV blood samples were detected to identify recent HIV infection in Tianjin during 2008-2015. Factors associated with HIV-1 infection were analyzed by the univariate and multivariate unconditional logistic regression. The recent HIV-1 infection proportion of homosexuals increased from 37.70% in 2008 to 83.68% in 2015. Those cases who aged ≤30 years (OR=1.53, 95%CI: 1.30-1.79), in han ethnic group (OR=1.40, 95%CI: 1.02-1.91), students (OR=1.79, 95%CI: 1.28-2.51) were more likely to be recent infected. The cases who had a high school education (OR=1.28, 95%CI: 1.05-1.56) or collage education (OR=1.23, 95%CI: 1.00-1.50) were more likely to be recent infected than those who had a primary school education. Compared with patients identified by hospitals, the recent HIV infections were more likely to be found through voluntary counseling and testing (VCT), STD outpatients, men who have sex with men (MSM) investigation and unpaid blood donors. Homosexual transmission has become the major route of HIV-1 recent infection in Tianjin.

[Effects of urethral fibrosis on urinary control after laparoscopic radical prostatectomy].

Objective: To determine the influence of urethral fibrosis on the recovery of urinary continence after laparoscopic radical prostatectomy. Method: A retrospective study of 203 patients from January 2010 to January 2014 who were underwent laparoscopic radical prostatectomy for prostate cancer in the First Affiliated Hospital of Fujian Medical University. The patients were divided into 2 groups according to preoperative T2-weighted magnetic resonance imaging of fibrosis status of the urethral wall and periurethral tissue. One hundred and forty-four(≤2 grade) and 59 (≥3 grade) were classified into the no/mild and severe urethral fibrosis groups respectively. Urinary continence at 1, 3, 6, 12 months after operation were compared between this two groups respectively. Result: There was no significant difference in the two groups with respect to age, body mass index (BMI), Charlson comorbidity index (CCI), international prostate symptom score (IPSS), prostate volume, preoperative prostate-specific antigen value, nerve-sparing procedure, postoperative Gleason score and pathological stage. The operation was completed successfully in all cases. With a median follow-up time of 15 months (ranged from 12 to 24 months), there was no statistical difference between the two groups in urinary continence at 1 month after operation (P>0.05). The incidences of continence in patients with no/mild fibrosis were significantly higher at 3, 6, 12 months after operation than those with severe fibrosis. (In the no/mild fibrosis group and severe fibrosis group, the continue rate at 3 mouths was 50.0% vs 28.8% P=0.005; at 6 mouths was 91.0% vs 59.3% P<0.001; at 12 mouths was 98.6% vs 88.1% P=0.003). Conclusion: Preoperative urethral fibrosis could be a significant predictor of recovery of the long-term urinary continence status after laparoscopic radical prostatectomy. Compared with no/mild fibrosis, severe fibrosis had worse long-term continence status.

Association between single nucleotide polymorphisms in AKT1 and the risk of prostate cancer in the Chinese Han population.

AKT1, also known as v-akt murine thymoma viral oncogene homolog 1, is involved in the regulation of cell-survival and anti-apoptotic activities, which may affect the pathogenesis of various cancers. However, the association between genetic variants of AKT1 and the risk of developing prostate cancer has not been investigated before. This study investigated the associations between three polymorphisms (rs1130214, rs3730358, and rs2494732) in AKT1 and the risk of development of prostate cancer in the Chinese Han population. Sequenom MassARRAY & iPLEX technology were used to genotype these polymorphisms in 493 Chinese Han patients with prostate cancer and 309 age-matched healthy individuals. Compared to the CC genotype of the rs3730358 polymorphism, the CT genotype of the same polymorphism was strongly associated with a decreased risk of prostate cancer (OR = 0.617, 95%CI = 0.390-0.976, P = 0.037). However, there was no significant difference between the allele frequency of the rs3730358 polymorphism and those of the other two polymorphisms (P > 0.05). Moreover, no significant difference was found in the haplotype analysis (P > 0.05). Our study found that the variant genotype CT of rs3730358 of AKT1 was associated with a decreased risk of prostate cancer, which suggested that this polymorphism could play an important role in the development of the disease.

Rural-urban differences in receiving guideline-recommended diabetes care and experiencing avoidable hospitalizations under a universal coverage health system: evidence from the past decade.

OBJECTIVES: Rural-urban differences in health remain a concern worldwide. Few studies have investigated the dynamic changes in health between rural and urban areas. This study aims to examine whether the rural-urban gap in patients' receipt of guideline-recommended care and avoidable hospitalizations has decreased in 10 years under a universal coverage health system. STUDY DESIGN: A retrospective cohort study design. METHODS: This study utilized nationwide health insurance claims data of 3 representative cohorts of patients with newly diagnosed type 2 diabetes in 2000, 2005, and 2010 in Taiwan. The two outcome variables were receipt of guideline-recommended care and avoidable hospitalizations for diabetes. Generalized estimating equations models were used to estimate the rural-urban differences while controlling for physician-clustering effects. RESULTS: Rural diabetic patients were less likely to receive guideline-recommended examinations/tests in 2000 (eß = 0.97; 95% confidence interval [CI]: 0.96-0.99); however, the average number of examinations/tests increased and the rural-urban difference had diminished in 2010. The likelihood of avoidable hospitalizations for diabetes among rural diabetic patients was higher than that for their urban counterparts in 2000 (odds ratio [OR]: 1.13; 95% CI: 1.01-1.25). Although the likelihood of avoidable hospitalizations for diabetes decreased from 2000 to 2010, the rural-urban gap remained during this period. CONCLUSIONS: The rural-urban disparity in receiving recommended diabetes care diminished over the past decade. However, significant gaps between rural and urban areas in avoidable hospitalizations for diabetes persisted despite the universal health system.

Quantitative trait loci mapping of the stigma exertion rate and spikelet number per panicle in rice (Oryza sativa L.).

The stigma exertion rate is a polygenic inherited trait that is important for increased seed yield in hybrid rice breeding. To identify quantitative trait loci (QTL) associated with high stigma exertion rate, we conducted QTL mapping using 134 recombinant inbred lines derived from XieqingzaoB and Zhonghui9308, which have high and low stigma exertion rates, respectively. A total of eight QTLs (qSES6, qSSE11, qDSE1a, qDSE1b, qDSE10, qDSE11, qTSE1, and qTSE11) for single stigma exertion, double stigma exertion, and total stigma exertion were detected. The locations of qSSE11 and qTSE11 have not been previously reported, and the qDSE11 allele from parent XQZB exhibited a positive additive effect. In addition, three QTLs (qSNP1, qSNP3a, and qSNP3b), for spikelet number per panicle were identified. Of note, one QTL (qSNP1) was detected in two different environments (Hainan and Zhejiang). To evaluate the advantage of exerted stigma for cross-pollination, single, dual, and total stigma exertion should be considered separately for future genetic improvement in the production of rice hybrid seeds. In addition, this study provides information for fine mapping, gene cloning, and marker assisted selection, with emphasis on the latter.

Exogenous Nitric Oxide Suppresses in Vivo X-ray-Induced Targeted and Non-Targeted Effects in Zebrafish Embryos.

The present paper studied the X-ray-induced targeted effect in irradiated zebrafish embryos (Danio rerio), as well as a non-targeted effect in bystander naïve embryos partnered with irradiated embryos, and examined the influence of exogenous nitric oxide (NO) on these targeted and non-targeted effects. The exogenous NO was generated using an NO donor, S-nitroso-N-acetylpenicillamine (SNAP). The targeted and non-targeted effects, as well as the toxicity of the SNAP, were assessed using the number of apoptotic events in the zebrafish embryos at 24 h post fertilization (hpf) revealed through acridine orange (AO) staining. SNAP with concentrations of 20 and 100 µM were first confirmed to have no significant toxicity on zebrafish embryos. The targeted effect was mitigated in zebrafish embryos if they were pretreated with 100 µM SNAP prior to irradiation with an X-ray dose of 75 mGy but was not alleviated in zebrafish embryos if they were pretreated with 20 µM SNAP. On the other hand, the non-targeted effect was eliminated in the bystander naïve zebrafish embryos if they were pretreated with 20 or 100 µM SNAP prior to partnering with zebrafish embryos having been subjected to irradiation with an X-ray dose of 75 mGy. These findings revealed the importance of NO in the protection against damages induced by ionizing radiations or by radiation-induced bystander signals, and could have important impacts on development of advanced cancer treatment strategies.

Mapping quantitative trait loci for nitrogen uptake and utilization efficiency in rice (Oryza sativa L.) at different nitrogen fertilizer levels.

Genetic improvement is the fundamental basis for improving nitrogen-use efficiency. A better understanding of genetic factors controlling nitrogen uptake and utilization is required for crop genetic improvement. In this study, we identified the quantitative trait loci (QTLs) associated with traits of nitrogen uptake and utilization by using the single-sequence repeat marker method and a recombinant inbred line (RIL) population derived from a super hybrid Xieyou9308. All the traits investigated were inherited quantitatively by continuous variation and showed normal distribution in phenotype with transgressive segregation in the RIL population. Most of the traits were significantly correlated with each other except for nitrogen absorption ability (NAA) with nitrogen harvest index (NHI) and NHI with agricultural nitrogen-absorption efficiency (ANAE). At logarithmic odds value of 2.3, total 13 candidate QTLs, including 4 for NAA, 2 for NHI, 2 for physiological nitrogen-use efficiency, 1 for agricultural nitrogen-use efficiency (ANUE), and 4 for ANAE, were detected and mapped on chromosomes 2, 3, 4, 5, 8, 9, 10, and 12. Significant pleiotropic effect or neighboring expression of QTLs was observed among traits. At position 64.8 cM on chromosome 4 near the marker RM5757, there was a QTL cluster of NAA, ANUE, and ANAE, and at chromosome 5 near the marker RM5968, there was a QTL cluster of NAA and ANUE. The QTL clusters might provide partial explanation and genetic mechanism for the observed correlations between nitrogen uptake and utilization efficiency traits and might form a basis for future breeding programs.

Toxicology study assessing efficacy and safety of repeated administration of lipid/DNA complexes to mouse lung.

For gene therapy to improve lung function in cystic fibrosis (CF) subjects, repeated administration of the gene transfer agent over the lifetime of patients is likely to be necessary. This requirement limits the utility of adenoviral and adeno-associated viral vectors (both previously evaluated in CF gene therapy trials) because of induced adaptive immune responses that render repeated dosing ineffective. For CF gene therapy trials, non-viral vectors are currently the only viable option. We previously showed that the cationic lipid formulation GL67A is the most efficient of several non-viral vectors analysed for airway gene transfer. Here, we assessed the efficacy and safety of administering 12 inhaled doses of GL67A complexed with pGM169, a CpG-free plasmid encoding human CFTR complementary DNA, into mice. We show that repeated administration of pGM169/GL67A to murine lungs is feasible, safe and achieves reproducible, dose-related and persistent gene expression (>140 days after each dose) using an aerosol generated by a clinically relevant nebuliser. This study supports progression into the first non-viral multidose lung trial in CF patients.

Innovative applications of immunisation registration information systems: example of improved measles control in Taiwan.

Immunisation registry systems have been shown to be important for finding pockets of under-immunised individuals and for increasing vaccination coverage. The National Immunisation Information System (NIIS) was established in 2003 in Taiwan. In this perspective, we present the construction of the NIIS and two innovative applications, which were implemented in 2009, which link the NIIS with other databases for better control of measles. Firstly, by linking the NIIS with hospital administrative records, we are able to follow up contacts of measles cases in a timely manner to provide the necessary prophylaxis, such as immunoglobulin or vaccines. Since 2009, there have been no measles outbreaks in hospitals in Taiwan. Secondly, by linking the NIIS with an immigration database, we are able to ensure that young citizens under the age of five years entering Taiwan from abroad become fully vaccinated. Since 2009, the measles-mumps-rubella vaccine coverage rate at two years of age has increased from 96% to 98%. We consider these applications of the NIIS to be effective mechanisms for improving the performance of infectious disease control in Taiwan. The experience gained could provide a valuable example for other countries.

Activity of the MEK inhibitor selumetinib (AZD6244; ARRY-142886) in nasopharyngeal cancer cell lines.

This study evaluated the preclinical activity of selumetinib (AZD6244, ARRY-142866), an inhibitor of the mitogen-activated protein kinase kinase (MAPKK or MEK1/2) in 6 nasopharyngeal cancer (NPC) cell lines. Selumetinib could achieve up to 90 % inhibition of cell growth with the respective IC(50) values in NPC cell lines as follow: HK1 = 0.04 µM, HK1-LMP1(B95.8) = 0.17 µM, HONE-1-EBV = 0.46 µM, HONE-1 = 1.79 µM, CNE-2 = 2.20 µM and C666-1 > 10 µM. The drug-sensitive cell lines HK1, HK1-LMP1(B95.8) and HONE-1-EBV have higher basal expression of phosphorylated (pi)-MAPK than the less sensitive cell lines. BRAF mutations were not detected in all 6 cell lines. Re-introduction of the EBV genome into HONE-1 cells, generating the HONE-1-EBV cell line, seemed to result in elevated expression of pi-MAPK and sensitivity to selumetinib when compared with the parental HONE-1 cells. At a concentration of 0.5 µM and 5 µM, selumetinib induced apoptosis (as indicated by cleaved PARP expression and caspase 3 induction), and G(0)/G(1) cycle arrest in HONE-1-EBV and HK1-LMP1(B95.8) cells. The combination of selumetinib (at IC(25) concentration) and the EGFR tyrosine kinase inhibitor, gefitinib (at concentrations of 0.1, 3 and 9 µM) resulted in synergistic growth inhibition in HK1-LMP1(B95.8) cells. The combination of selumetinib (at IC(25) concentration) and cisplatin (at concentrations of 0.1, 0.4, 0.8 and 2 µM) resulted in synergistic growth inhibition in HONE-1 and HONE-1-EBV cells. This result suggests that selumetinib alone or in combination with gefitinib or cisplatin maybe a promising strategy against NPC. Further studies are warranted.

Bystander effect between zebrafish embryos in vivo induced by high-dose X-rays.

We employed embryos of the zebrafish, Danio rerio, for our studies on the in vivo bystander effect between embryos irradiated with high-dose X-rays and naive unirradiated embryos. The effects on the naive whole embryos were studied through quantification of apoptotic signals at 25 h post fertilization (hpf) through the terminal dUTP transferase-mediated nick end-labeling (TUNEL) assay followed by counting the stained cells under a microscope. We report data showing that embryos at 5 hpf subjected to a 4-Gy X-ray irradiation could release a stress signal into the medium, which could induce a bystander effect in partnered naive embryos sharing the same medium. We further demonstrated that this bystander effect (induced through partnering) could be successfully suppressed through the addition of the nitric oxide (NO) scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) into the medium but not through the addition of the CO liberator tricarbonylchloro(glycinato)ruthenium(II) (CORM-3). This shows that NO was involved in the bystander response between zebrafish embryos induced through X-ray irradiation. We also report data showing that the bystander effect could be successfully induced in naive embryos by introducing them into the irradiated embryo conditioned medium (IECM) alone, i.e., without partnering with the irradiated embryos. The IECM was harvested from the medium that had conditioned the zebrafish embryos irradiated at 5 hpf with 4-Gy X-ray until the irradiated embryos developed into 29 hpf. NO released from the irradiated embryos was unlikely to be involved in the bystander effect induced through the IECM because of the short life of NO. We further revealed that this bystander effect (induced through IECM) was rapidly abolished through diluting the IECM by a factor of 2× or greater, which agreed with the proposal that the bystander effect was an on/off response with a threshold.

Generation and characterization of a delta F508 cystic fibrosis mouse model.

We have generated mice carrying the most common mutation in cystic fibrosis (CF), delta F508, within the cystic fibrosis (Cftr) gene. Mutant animals show pathological and electrophysiological changes consistent with a CF phenotype. delta F508-/- mice die from peritonitis and show deficiencies in cAMP-activated electrogenic Cl- transport. These mice produce delta F508 transcripts and show the temperature-dependent trafficking defect first described for the human delta F508 CFTR protein. A functional CFTR Cl- channel not demonstrated by null CF mice or present at 37 degrees C was detected following incubation of epithelial cells at 27 degrees C. Thus, these mice are an accurate delta F508 model and will be valuable for testing drugs aimed at overcoming the delta F508 trafficking defect.

The threshold number of protons to induce an adaptive response in zebrafish embryos.

In this study, microbeam protons were used to provide the priming dose to induce an in vivo radioadaptive response (RAR) in the embryos of zebrafish, Danio rerio, against subsequent challenging doses provided by x-ray photons. The microbeam irradiation system (Single-Particle Irradiation System to Cell, acronym SPICE) at the National Institute of Radiological Sciences (NIRS), Japan, was employed. The embryos were dechorionated at 4 h post fertilisation (hpf) and irradiated at 5 hpf by microbeam protons. For each embryo, one irradiation point was chosen, to which 5, 10, 20, 30, 40, 50, 100, 200, 300 and 500 protons each with an energy of 3.4 MeV were delivered. The embryos were returned to the incubator until 10 hpf to further receive the challenging exposure, which was achieved using 2 Gy of x-ray irradiation, and then again returned to the incubator until 24 hpf for analyses. The levels of apoptosis in zebrafish embryos at 25 hpf were quantified through terminal dUTP transferase-mediated nick end-labelling (TUNEL) assay. The results revealed that at least 200 protons (with average radiation doses of about 300 and 650 mGy absorbed by an irradiated epithelial and deep cell, respectively) would be required to induce RAR in the zebrafish embryos in vivo. Our previous investigation showed that 5 protons delivered at 10 points on an embryo would already be sufficient to induce RAR in the zebrafish embryos. The difference was explained in terms of the radiation-induced bystander effect as well as the rescue effect.

Adaptive response to ionising radiation induced by cadmium in zebrafish embryos.

An adaptive response is a biological response where the exposure of cells or animals to a low priming exposure induces mechanisms that protect the cells or animals against the detrimental effects of a subsequent larger challenging exposure. In realistic environmental situations, living organisms can be exposed to a mixture of stressors, and the resultant effects due to such exposures are referred to as multiple stressor effects. In the present work we demonstrated, via quantification of apoptosis in the embryos, that embryos of the zebrafish (Danio rerio) subjected to a priming exposure provided by one environmental stressor (cadmium in micromolar concentrations) could undergo an adaptive response against a subsequent challenging exposure provided by another environmental stressor (alpha particles). We concluded that zebrafish embryos treated with 1 to 10 µM Cd at 5 h postfertilisation (hpf) for both 1 and 5 h could undergo an adaptive response against subsequent ~4.4 mGy alpha-particle irradiation at 10 hpf, which could be interpreted as an antagonistic multiple stressor effect between Cd and ionising radiation. The zebrafish has become a popular vertebrate model for studying the in vivo response to ionising radiation. As such, our results suggested that multiple stressor effects should be carefully considered for human radiation risk assessment since the risk may be perturbed by another environmental stressor such as a heavy metal.