Precision Measurement of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Cross Section Near Threshold

The cross section of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} process is measured with unprecedented precision using data collected with the BESIII detector at sqrt[s]=4574.5, 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} production threshold is cleared. At center-of-mass energies sqrt[s]=4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ_{c} polar angle distributions. From these, the Λ_{c} electric over magnetic form-factor ratios (|G_{E}/G_{M}|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03, respectively, where the first uncertainties are statistical and the second are systematic.

HPV16 DNA and integration in normal and malignant epithelium: implications for the etiology of laryngeal squamous cell carcinoma

Background

Molecular evidence suggests that human papillomavirus (HPV) has a role in the etiology of oropharyngeal squamous cell carcinoma. However, the role of HPV in laryngeal squamous cell carcinoma (LSCC) is unclear.

Patients and methods

We conducted a case–control study using tumor tissue specimens from 300 LSCC patients and vocal cord polyp specimens from 300 cancer-free controls. HPV genotype, HPV16 viral load and viral integration status, and p16 expression were determined.

Results

The prevalence of HPV (all types) was higher in cases than controls [21 (7.0%) versus 10 (3.3%), adjusted odds ratio (aOR) 2.37, 95% CI 1.08–5.21]. The prevalence of HPV16 was higher in cases than controls [20 (6.7%) versus 8 (2.7%), aOR 2.84, 95% CI 1.21–6.68]. The risk of LSCC associated with HPV16 DNA positivity was even higher in patients aged 55 years or younger (aOR 3.52, 95% CI 1.07–11.54), males (aOR 4.74, 95% CI 1.33–16.90), never-smokers (aOR 5.57, 95% CI 1.41–22.10), and never-drinkers (aOR 3.72, 95% CI 1.09–12.72). HPV DNA was partly or fully integrated in all 20 HPV16-positive cases but was episomal in all 8 HPV16-positive controls; however, the HPV16-positive cases and controls had similar viral loads (P = 0.28). P16 immunostaining was positive in 31 of the 300 cases (10.3%) and negative in all 300 controls.

Conclusion

These results suggest that prior infection with HPV16 may play a role in the etiology of some LSCC. This larger case–control study will offer for the first time the possibility to address in depth the understanding of a tissue-specific role of HPV in laryngeal carcinogenesis. Further studies with larger samples are needed to confirm these findings.

Interpretation of liver stiffness measurement-based approach for the monitoring of hepatitis B patients with antiviral therapy: A 2-year prospective study

Liver biopsy is not routinely performed in treated chronic hepatitis B. Liver stiffness measurement has been validated for noninvasive liver fibrosis assessment in pretreatment chronic hepatitis B but has not been assessed for fibrosis monitoring during antiviral therapy. Liver stiffness was systemically monitored by Fibroscan^® every 6 months in a cohort of patients with hepatitis B receiving antiviral therapy and compared with liver biopsies at baseline and week 104. A total of 534 hepatitis B e antigen-positive treatment-naive patients receiving telbivudine-based therapy with qualified liver stiffness measurement at baseline and week 104 were analyzed, 164 of which had adequate paired liver biopsies. Liver stiffness decreased rapidly (-2.2 kPa/24 weeks) in parallel with alanine aminotransferase (ALT) from 8.6 (2.6-49.5) kPa at baseline to 6.1 (2.2-37.4) kPa at week 24. Interestingly, liver stiffness decreased slowly (-0.3 kPa/24 weeks) but continually from week 24 to week 104 (6.1 vs 5.3 kPa, P < .001) while ALT levels remained stable within the normal range. More importantly, liver stiffness declined significantly irrespective of baseline ALT levels and liver necroinflammation grades. From baseline to week 104, the proportion of patients with no or mild fibrosis (Ishak, 0-2) increased from 74.4% (122/164) to 93.9% (154/164). Multivariate analysis revealed that percentage decline of 52-week liver stiffness from baseline was independently associated with 104-week liver fibrosis regression (odds ratio, 3.742; P = .016). Early decline of 52-week liver stiffness from baseline may reflect the remission of both liver inflammation and fibrosis and was predictive of 104-week fibrosis regression in treated patients with chronic hepatitis B.

Characterization of CD45RO+ memory T lymphocytes in keloid disease

BACKGROUND

Memory T cells, a highly effective subset of T lymphocytes, have been reported to be involved in many inflammatory skin disorders. However, the potential role of memory T cells in keloid disease (KD) remains unclear.

OBJECTIVES

Due to their important role in regulating inflammation, we investigated the characteristics of CD45RO⁺ memory T cells in KD.

METHODS

Primary cutaneous cells were isolated from keloid scars and normal skin by enzymic digestion. Peripheral blood mononuclear cells were isolated from a related blood sample, and flow cytometry was applied to identify the phenotypic and functional abnormalities of memory T cells in KD.

RESULTS

We observed that the majority of T lymphocytes in keloid scars had the memory phenotype, and a greater number of the CD8⁺ memory T cells in keloid scars produced lower levels of tumour necrosis factor (TNF)-α. This abnormal cytokine production was even more distinct in Forkhead box (FOX)P3^-  CD8^- memory T cells, with lower TNF-α production and enhanced interferon-γ production. Furthermore, FOXP3⁺  CD8^- memory T cells in keloid scars were abnormal, including showing reduced CD25 and cytotoxic T-lymphocyte-associated antigen 4 expression and interleukin-10 production. In addition, a significant decrease in the number of CD4⁺  CD25^high  FOXP3⁺ regulatory T cells was identified in patients with multiple keloid scars. We also found that there was significantly increased infiltration of CD103⁺  CD8⁺ memory T cells in keloid scars.

CONCLUSIONS

Our findings preliminarily elucidate the abnormalities of CD45RO⁺ memory T cells in keloid scars and provide early evidence that a disrupted T-cell response contributes to the progression of KD.

CT quantitative parameters to predict the invasiveness of lung pure ground-glass nodules (pGGNs)

AIM

To investigate the value of computed tomography (CT) quantitative parameters in predicting the invasiveness of lung pure ground-glass nodules (pGGNs).

MATERIALS AND METHODS

Chest CT images and pathological findings of 163 pGGNs in 154 consecutive patients were reviewed. According to the clinical management strategies, cases were divided into pre-invasive and MIA groups (atypical adenomatous hyperplasia [AAH], adenocarcinoma in situ [AIS], and minimally invasive adenocarcinoma [MIA]) and invasive group (invasive adenocarcinoma [IAC]). CT quantitative parameters including maximum diameter, largest diameter perpendicular to the maximum diameter, maximum cross-sectional area, volume, mass, and mean attenuation value were measured and compared between two groups. Their diagnostic performances were evaluated using receiver operating characteristic (ROC) and logistic regression analysis.

RESULTS

Significant differences existed for all the CT quantitative parameters in both groups (p<0.01). The values of area under the curve (AUC) were 0.783 of maximum diameter (95% CI: 0.711-0.843), 0.779 of longest diameter perpendicular to maximum diameter (95% CI: 0.707-0.840), 0.796 of largest cross-sectional area (95% CI: 0.726-0.855), 0.781 of volume (95% CI: 0.710-0.842), 0.794 of mass (95% CI: 0.722-0.865) and 0.625 of mean attenuation value (95% CI: 0.546-0.700), respectively. A pairwise-manner comparison showed the AUC of mean attenuation value was the smallest (p<0.01). Logistic regression analysis showed the largest cross-sectional area (OR=2.307, 95% CI: 1.689-3.150) was the independent predictor for IAC with a cut-off value of 2.22 cm².

CONCLUSIONS

CT quantitative parameters could predict the invasiveness of lung pGGNs. The largest cross-sectional area is the most valuable independent predictor and the mean attenuation value is less valuable.

Note: Development of a multichannel magnetic probe array for magnetohydrodynamic activity studies in Sino-United Spherical Tokamak

A 30-channel movable magnetic probe radial array measuring the poloidal magnetic field's time derivative Ḃ_θ has been developed and installed on the Sino-United Spherical Tokamak to investigate the magnetohydrodynamic (MHD) activities in ohmic discharges. The probe array consists of thirty identical commercial chip inductors mounted on a slim printed circuit board and shielded by a customized quartz tube of 14 mm in outer diameter. With the application of instrumentation amplifiers, the system exhibits a good signal to noise ratio and the measured vertical field spatial distribution agrees well with the simulation result. The measured spatial and temporal distribution of Ḃ_θ during the MHD activities exhibits a clear phase reversal layer, which is a direct proof of tearing mode and provides a reliable indication of the magnetic island chain position.

[Outcome of patients with coronary artery disease and left ventricular ejection fraction less than 50% undergoing percutaneous coronary intervention]

Objective: To investigate the in-hospital and long-term outcomes of patients with left ventricular ejection fraction (LVEF) <50% undergoing percutaneous coronary intervention (PCI) . Methods: From January to December 2013, 10 445 consecutive patients who underwent PCI in Fuwai Hospital and the LVEF value was available were prospectively included. The patients were divided into LVEF≥50% group (9 896 cases) and LVEF<50% group (549 cases) . The in-hospital and 2-year clinical outcomes were compared between the 2 groups. The association between LVEF<50% and clinical outcomes was assessed using multivariable Cox regression analysis. Results: (1) Compared with LVEF ≥50% group, LVEF< 50% group had higher rates of in-hospital all-cause death (1.1% (6/549) vs. 0.2% (17/9 896) , P<0.01) , cardiac death (1.1% (6/549) vs. 0.1% (12/9 896) , P<0.01) , in-stent thrombosis (0.7% (4/549) vs. 0.2% (18/9 896) , P<0.01) , myocardial infarction (2.4% (13/549) vs. 1.2% (121/9 896) , P<0.05) ,and major adverse cardiovascular and cerebrovascular events (MACCE) which including death, myocardial infarction, revascularization, in-stent thrombosis, and stroke (3.6% (20/549) vs. 1.4% (137/9 896) , P<0.01) . (2) A total of 10 388 (99.5%) patients completed 2-year follow-up. Compared with LVEF ≥50% group, LVEF<50% group had higher rates of 2-year all-cause death (4.7% (26/549) vs. 1.0% (101/9 896) , P<0.01) , cardiac death (4.0% (22/549) vs. 0.5% (50/9 896) , P<0.01) , in-stent thrombosis (3.1% (17/549) vs. 0.7% (71/9 896) , P<0.001) , myocardial infarction (4.2% (23/549) vs. 1.9% (186/9 896) , P<0.01) ,and MACCE (17.9% (98/549) vs. 11.8% (1 172/9 896) , P<0.01) . There were no significant differences on the rates of 2-year target-vessel revascularization, bleeding and stroke between the two groups. (3) The multivariable Cox regression analysis demonstrated that LVEF< 50% was the independent risk factor of 2-year all-cause death (HR=2.47, 95%CI 1.49-4.08, P<0.01) , cardiac death (HR=3.25, 95%CI 1.79-5.90, P<0.01) , in-stent thrombosis (HR=4.19, 95%CI 2.39-7.34, P<0.01) , myocardial infarction (HR=2.00, 95%CI 1.26-3.16, P<0.01) , and MACCE (HR=1.40, 95%CI 1.13-1.74, P<0.01) . (4) After propensity score matching, all in-hospital outcomes were similar between the two groups, including all-cause death, cardiac death, in-stent thrombosis, myocardial infarction, revascularization, bleeding, stroke, and MACCE (all P>0.05) . After propensity score matching,the multivariable Cox regression analysis demonstrated that LVEF<50% was still an independent risk factor of 2-year all-cause death (HR=3.08, 95%CI 1.37-6.89, P<0.01) , cardiac death (HR= 4.12, 95%CI 1.53-11.07, P<0.01) ,and in-stent thrombosis (HR=3.82, 95%CI 1.27-11.5, P<0.05) . Conclusion: LVEF< 50% is an independent risk factor of 2-year all-cause death, cardiac death, and in-stent thrombosis in patients undergoing PCI, but it does not increase the risk of target-vessel revascularization, bleeding or stroke.

[Efficacy comparison of 3 strategies for real-world stable coronary artery disease patients with three-vessel disease]

Objective: To compare the effectiveness of percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) or medical therapy (MT) alone for real-world stable coronary artery disease (SCAD) patients with three-vessel disease (TVD) in mainland China. Methods: A total of 8 943 consecutive cases with TVD hospitalized in our center from April 2004 to February 2011 were screened for this study. In this cohort, 3 435 cases diagnosed as SCAD were analyzed. PCI, CABG, MT alone were performed in 1 313 (38.2%), 1 259 (36.7%) and 863 (25.1%) patients, respectively. Propensity score matching (PSM) analysis using nearest neighbor matching with a 1∶1 ratio was applied, and 758 pairs of CABG and PCI groups, 552 pairs of PCI and MT groups, 639 pairs of CABG and MT groups were selected, respectively. 1- and 2-year clinical outcomes were evaluated among PCI, CABG and MT group. Kaplan-Meier curves and multivariable Cox regression method were used for survival analysis. Results: Significant differences were found at baseline between PCI, CABG and MT group, including age, gender, body mass index, family history of coronary artery disease, hyperlipidemia, diabetes mellitus, previous myocardial infarction, stroke, previous revascularization, peripheral vascular disease, SNYTAX score, left ventricular ejection fraction, hemoglobin, serum creatinine, high-sensitivity C-reactive protein, triglyceride and medication (all P<0.05) . All-cause death rates of 1- and 2-year follow-up of PCI, CABG and MT group were 0.6% (8/1 313), 1.1% (14/1 259), 3.4% (29/863) (P<0.001) and 1.1%(14/1 313), 1.5%(19/1 259), 7.3%(63/863) (P<0.001), respectively. Multivariate Cox regression analysis showed that 1-year MACCE rate (HR=0.51, 95%CI 0.33-0.77, P=0.001) was significantly reduced, due to the significant decrease of myocardial infarction (MI) rate (HR=0.09, 95%CI 0.01-0.76, P=0.027) and repeat revascularization rate (HR=0.21, 95%CI 0.10-0.41, P<0.001) in CABG group compared to PCI group, while all-cause death (HR=1.21, 95%CI 0.48-3.00, P=0.69) and stroke rate (HR=2.31, 95%CI 0.82-6.47, P=0.112) were similar between 2 groups. 2-year outcome showed CABG was associated with higher stroke rate (HR=2.20, 95%CI 1.06-4.55, P=0.034) and lower MI (HR=0.19, 95%CI 0.06-0.59, P=0.004) and repeat revascularization rate (HR=0.22, 95%CI 0.13-0.37, P<0.001), and lower MACCE rate (HR=0.49, 95%CI 0.36-0.68, P<0.001). Compared to MT group, 2-year all-cause death (HR=0.22, 95%CI 0.12-0.42, P<0.001) and MACCE rate (HR=0.63, 95%CI 0.47-0.83, P=0.001) were lower in PCI group, while 2-year all-cause death (HR=0.21, 95%CI 0.13-0.37, P<0.001), MACCE (HR=0.31, 95%CI 0.23-0.42, P<0.001), MI (HR=0.19, 95%CI 0.06-0.60, P=0.004) and repeat revascularization rate (HR=0.24, 95%CI 0.13-0.41, P<0.001) were lower in CABG group. Results of multivariate Cox regression analysis after PSM were consistent with above results. Conclusion: For SCAD patients with TVD, CABG shows better effectiveness by reducing MI and revascularization risk as compared to PCI, even though stroke risk is somehow higher in CABG patients. Patients received MT alone are associated with worse outcomes than those undergoing revascularization strategies.

Safety, quality and effect of complete mesocolic excision vs non-complete mesocolic excision in patients with colon cancer: a systemic review and meta-analysis

AIM

The application of complete mesocolic excision (CME) in colon cancer is controversial. We performed a meta-analysis to compare the safety, quality and effect of CME with non-complete mesocolic excision (NCME) in patients with colon cancer.

METHOD

We searched PubMed, ScienceDirect, the Cochrane Library and Scopus to identify studies comparing CME with NCME in colon cancer. We focused on three study outcome areas: safety (operation time, blood loss, complications, mortality); quality (large bowel length, distance from the tumour to the high vascular tie, area of mesentery, total lymph nodes); and effect (long-term survival).

RESULTS

A total of 8586 patients from 12 studies were included in the meta-analysis. CME was associated with greater intra-operative blood loss [weighted mean difference (WMD) 79.87, 95% CI: 65.88-93.86], more postoperative surgical complications (relative risk 1.23, 95% CI: 1.08-1.40), longer large bowel resection (WMD 47.06, 95% CI: 10.49-83.62), greater distance from the tumour to the high vascular tie (WMD 17.51, 95% CI: 15.16-19.87), larger area of mesentery (WMD 36.09, 95% CI: 18.06-54.13) and more lymph nodes (WMD 6.13, 95% CI: 1.97-10.28) than NCME. CME also had positive effects on 5-year survival [hazard ratio (HR) 0.33, 95% CI: 0.13-0.81], 3-year survival (HR 0.58, 95% CI: 0.39-0.86) and 3-year survival for Stage III disease (HR 0.69, 95% CI: 0.60-0.80) compared with NCME.

CONCLUSION

Limited evidence suggests that CME is a more effective strategy for improving specimen quality and survival but with a higher complication rate.

[Clinical characteristics and prognosis in the patients of stroke after percutaneous coronary intervention]

Objective: To investigate the clinical characteristics and prognosis in patients with stroke after percutaneous coronary intervention (PCI). Methods: From January 2013 to December 2013, 10 724 consecutive patients undergoing PCI including acute coronary syndrome and stable angina pectoris were enrolled.A two years' follow up was conducted among these patients to investigate the clinical characteristics and prognosis of patients with stroke and of those without. A comparison was done between the two groups. Results: One hundred and forty-five patients had stroke (1.4%) during the follow-up period after PCI, including 124 cases with ischemic stroke (1.2%), out of whom 4 (3.2%) patients died; 21 cases with hemorrhagic stroke, out of whom 9 patients (42.9%) died.There was more female, and more patients with risks factors, hypertension, previous myocardial infarction, previous stroke, etc. in the patients with stroke.During the 2-year follow-up, patients with stroke experienced higher incidence of all-cause mortality (9% vs 1.1%, P<0.000 1). There were no significant differences in the incidences of cardiac death, myocardial infarction, revascularization, stent thrombosis and major adverse cardiovascular event rates between the two groups.COX regression analysis showed that stroke after PCI was associated with the increased mortality (HR=8.387, 95%CI: 4.725-14.855, P<0.000 1). Meanwhile, after propensity score matched analyses (129 pairs), the trend was not changed, and stroke was still an independent risk factor of all-cause mortality (HR=6.737, 95%CI: 1.52-29.85, P=0.012). Conclusions: The patients underwent PCI, who had stroke later, had more clinical risk factors, and more serious degree of atherosclerosis.The incidence of stroke is an independent risk factor for all-cause mortality in patients with coronary heart disease after PCI.

Human Adipose-Derived Stem Cells Delay Retinal Degeneration in Royal College of Surgeons Rats Through Anti-Apoptotic and VEGF-Mediated Neuroprotective Effects

Stem cell therapy is a promising therapeutic approach for retinal degeneration (RD). Our study investigated the effects of human adipose derived stem cell (hADSCs) on Royal College of Surgeons (RCS) rats.

METHODS

Green fluorescent protein (GFP)-labeled hADSCs were transplanted subretinally into RCS rats at postnatal (PN) 21 days to explore potential therapeutic effects, while adeno-associated viral vector (AAV2)-vascular endothelial growth factor (VEGF) and siVEGF-hADSCs were used to aid the mechanistic dissections. Visual function was evaluated by Electroretinogram (ERG) recording. Potential transdifferentiations were examined by Immunofluorescence (IF) and gene expressions were analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Apoptotic retinal cells were detected by Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling (TUNEL) assay and the cytokines secreted by hADSCs were measured by Enzyme-linked Immunosorbent Assay (ELISA).

RESULTS

The visual function of RCS rats began to decrease one week after their eyes opened at PN week 3 and almost lost in PN 5 weeks, accompanied by the loss of retinal outer nuclear layer (ONL). Subretinal transplantation of hADSCs significantly improved the visual function 2 weeks after the transplantation and such therapeutic effect persisted up to 8 weeks after the treatment (PN 11 weeks), with 3-4 rows of photoreceptors remained in the ONL and reduced apoptosis. Consistent with these phenotypic changes, the gene expression of rod photoreceptor markers Rhodopsin (Rho), Crx and Opsin (Opn1) in RCS rats showed obvious decreasing trends over time after PN 3 weeks, but were elevated with hADSC treatment. hADSC transplantation also repressed the expressions of Bax, Bak and Caspase 3, but not the expression of anti-apoptotic genes, including Bcl-2 and Bcl-XL. Finally, substantial VEGF, hepatocyte growth factor (HGF) and pigment epithelium-derived factor (PEDF) secretions from hADSCs were detected, while endogenous Vegf expression level decreased over time in RCS rats. The treatment of AAV2-VEGF showed comparable therapeutic effects as hADSCs but siRNA knockdown of VEGF in hADSCs essentially abolished the therapeutic effects.

CONCLUSIONS

Subretinal transplantation of hADSCs in RCS rats effectively delayed the retinal degeneration, enhanced the retinal cell survival and improved the visual function. Mechanistically this was mainly due to hADSC dependent anti-apoptotic and neuroprotective effects through its secretion of growth and neurotrophic factors including VEGF. Clinical application of hADSCs merits further investigation.

A new dispersion interferometer on HL-2A

In order to avoid a fringe jump caused by high plasma density and pellet injection [Y. Zhou et al., Rev. Sci. Instrum. 87, 11E107 (2016)], a new CO₂ dispersion interferometer is designed and commissioned on HL-2A for average line-density measurement and density feedback control. The second harmonic technology in this system eliminates the phase shift caused by mechanical vibration. Signals are processed by a digital phase comparator and can be monitored in real time. A series of experiments are conducted to study the characteristics of the system such as a second harmonic coefficient and long-term stability. The resolution of density measurement is less than 8 × 10¹⁷/m³, and the experiment result on HL-2A demonstrates the interferometer's capability to track plasma density evolution with rapid change. The system also shows good stability against mechanical vibrations.

Determination of eddy current response with magnetic measurements

Accurate mutual inductances between magnetic diagnostics and poloidal field coils are an essential requirement for determining the poloidal flux for plasma equilibrium reconstruction. The mutual inductance calibration of the flux loops and magnetic probes requires time-varying coil currents, which also simultaneously drive eddy currents in electrically conducting structures. The eddy current-induced field appearing in the magnetic measurements can substantially increase the calibration error in the model if the eddy currents are neglected. In this paper, an expression of the magnetic diagnostic response to the coil currents is used to calibrate the mutual inductances, estimate the conductor time constant, and predict the eddy currents response. It is found that the eddy current effects in magnetic signals can be well-explained by the eddy current response determination. A set of experiments using a specially shaped saddle coil diagnostic are conducted to measure the SUNIST-like eddy current response and to examine the accuracy of this method. In shots that include plasmas, this approach can more accurately determine the plasma-related response in the magnetic signals by eliminating the field due to the eddy currents produced by the external field.

Determination of the Spin and Parity of the Z_{c}(3900)

The spin and parity of the Z_{c}(3900)^{±} state are determined to be J^{P}=1^{+} with a statistical significance larger than 7σ over other quantum numbers in a partial wave analysis of the process e^{+}e^{-}→π^{+}π^{-}J/ψ. We use a data sample of 1.92  fb^{-1} accumulated at sqrt[s]=4.23 and 4.26 GeV with the BESIII experiment. When parametrizing the Z_{c}(3900)^{±} with a Flatté-like formula, we determine its pole mass M_{pole}=(3881.2±4.2_{stat}±52.7_{syst})  MeV/c^{2} and pole width Γ_{pole}=(51.8±4.6_{stat}±36.0_{syst})  MeV. We also measure cross sections for the process e^{+}e^{-}→Z_{c}(3900)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-} and determine an upper limit at the 90% confidence level for the process e^{+}e^{-}→Z_{c}(4020)^{+}π^{-}+c.c.→J/ψπ^{+}π^{-}.

Dengue virus infections among blood donors in Guangxi of China, 2013-2014

BACKGROUND

An unexpected, large dengue outbreak, spreading to 20 cities of Guangdong province, occurred in July 2014. Considering the overwhelming influence of this seasonal epidemic, whether this dengue virus outbreak has an significant impact on the blood donors of the ajacent areas in Guangdong requires at least a preliminary investigation. Liuzhou City of Guangxi was chosen as a good representative of the neighbouring geographical location of the dengue virus (DENV) outbreak areas in this research. We therefore investigated qualified blood donations during potential dengue epidemic seasons and thus provided critical information for public health and donation policy making.

METHOD

A total of 1685 donations from 2013 to 2014 were collected at the Guangxi blood centre. Anti-DENV testing was performed using enzyme-linked immunosorbent assay (ELISA). Dengue IgG indirect ELISA and Dengue IgM capture ELISA were used to detect anti-DENV IgM and IgG. Repeat-reactive samples with ELISA test and 1685 donations with 421 pools were screened for dengue RNA by reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) using an in-house assay.

RESULTS

There was a total of 13 seropositive donors, including 6 IgM seropositive and 7 IgG seropositive. The total seropositive rate was 0·78%, with IgM 0·36% and IgG 0·42%. Seropositive donors were identified mostly between April and November, with a peak in November. .All samples in reactive pools and individual seropositive samples were negative in the follow-up RT-PCR test.

CONCLUSION

Our results suggested that the Guangdong dengue outbreak had limited impact on blood safety in surrounding areas under our current testing system.

Plastic deformation mechanisms in a new Ni-base single crystal superalloy at room temperature

The evolution of dislocation configurations in a new Ni-base single crystal superalloy, M4706, during tensile deformation at room temperature is characterised by transmission electron microscopy. Experimental results show that contrary to previous reports, numerous isolated superlattice stacking faults and extended stacking faults are formed in the slightly deformed specimens with and without tertiary γ' precipitates. Meanwhile, it is also found that as the plastic deformation proceeds, the dominant deformation mechanism changes from stacking fault shearing to antiphase boundary shearing. Finally, based on experimental observations, the reasons for the formation of these faults and the transition in the deformation mechanism are discussed.

Application of endoscopy to treat mandibular keratocystic odontogenic tumors

The aim of this study was to evaluate the feasibility of endoscopy to remove keratocystic odontogenic tumors (KCOTs) with virtual 3D mandibular images. Fifteen patients (mean age, 40.27±14.58 years) who underwent endoscopic mandibular KCOT enucleation between May 2009 and October 2009 were included. Virtual 3D mandibular reconstructions derived from computed tomography (CT) imaging were generated for all patients. Recurrence and pathological fracture were evaluated as the primary outcome variables at 1 and 12 months after operation. Secondary infection and inferior alveolar nerve injury were evaluated as the secondary outcome variables at 1 and 6 months after operation. None of the 15 patients exhibited signs of recurrence or pathological fracture after operation. During long-term follow-up, no symptoms of inferior alveolar nerve injury or secondary infection were observed and no signs of recurrence were found in any of the patients. Endoscopy helps surgeons to remove mandibular KCOTs with small incisions. Moreover, endoscopy can provide clear and magnified views and help to avoid damage to the inferior alveolar neurovascular bundle. Therefore, under the support of preoperative virtual 3D mandibular images, the application of endoscopy to remove the tumors should be considered to be a treatment option for KCOTs.