[Research progress of anesthesia methods in prostate biopsy].

Prostate biopsy is the gold standard for the diagnosis of prostate cancer. In order to successfully and effectively complete the biopsy, clinicians should not only select the correct puncture method, but also pay attention to the pain control of patients undergoing puncture. It is necessary to select a reasonable anesthetic method for biopsy. The pain during biopsy comes from the skin, muscle and other structures in the puncture approach, and also comes from the prostate capsule. Therefore, the anesthesia emphasis of transperineal and transrectal biopsy approaches will also be different. The use of appropriate anesthesia is of great significance to improve the patient's cooperation and ensure the success rate of biopsy. With the continuous maturity of the technology and concept of prostate biopsy, a single anesthesia method has been unable to meet the actual anesthetic needs of biopsy, and the use of multi-site and multi-phase combined anesthesia for different sources of pain has become the mainstream anesthetic option.

First Directional Measurement of Sub-MeV Solar Neutrinos with Borexino.

We report the measurement of sub-MeV solar neutrinos through the use of their associated Cherenkov radiation, performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The measurement is achieved using a novel technique that correlates individual photon hits of events to the known position of the Sun. In an energy window between 0.54 to 0.74 MeV, selected using the dominant scintillation light, we have measured 10 887_{-2103}^{+2386}(stat)±947(syst) (68% confidence interval) solar neutrinos out of 19 904 total events. This corresponds to a ^{7}Be neutrino interaction rate of 51.6_{-12.5}^{+13.9} counts/(day·100 ton), which is in agreement with the standard solar model predictions and the previous spectroscopic results of Borexino. The no-neutrino hypothesis can be excluded with >5σ confidence level. For the first time, we have demonstrated the possibility of utilizing the directional Cherenkov information for sub-MeV solar neutrinos, in a large-scale, high light yield liquid scintillator detector. This measurement provides an experimental proof of principle for future hybrid event reconstruction using both Cherenkov and scintillation signatures simultaneously.

Improved Measurement of Solar Neutrinos from the Carbon-Nitrogen-Oxygen Cycle by Borexino and Its Implications for the Standard Solar Model.

We present an improved measurement of the carbon-nitrogen-oxygen (CNO) solar neutrino interaction rate at Earth obtained with the complete Borexino Phase-III dataset. The measured rate, R_{CNO}=6.7_{-0.8}^{+2.0} counts/(day×100 tonnes), allows us to exclude the absence of the CNO signal with about 7σ C.L. The correspondent CNO neutrino flux is 6.6_{-0.9}^{+2.0}×10^{8} cm^{-2} s^{-1}, taking into account the neutrino flavor conversion. We use the new CNO measurement to evaluate the C and N abundances in the Sun with respect to the H abundance for the first time with solar neutrinos. Our result of N_{CN}=(5.78_{-1.00}^{+1.86})×10^{-4} displays a ∼2σ tension with the "low-metallicity" spectroscopic photospheric measurements. Furthermore, our result used together with the ^{7}Be and ^{8}B solar neutrino fluxes, also measured by Borexino, permits us to disfavor at 3.1σ C.L. the "low-metallicity" standard solar model B16-AGSS09met as an alternative to the "high-metallicity" standard solar model B16-GS98.

Remdesivir as a broad-spectrum antiviral drug against COVID-19.

OBJECTIVE: List the clinical data of the role of remdesivir in COVID-19, and try to make an objective evaluation and analyze its feasibility. MATERIALS AND METHODS: The keywords of "remdesivir", "COVID-19" and "SARS-CoV-2" were systematically searched in PubMed and Web of Science. After removing the repetitions, we summarize articles, letters, and comments on remdesivir in the treatment of COVID-19. RESULTS: In this review, we summarize clinical case of using remdesivir in the treatment of COVID-19, analyzed the final treatment results, and judged whether the drug was effective for the treatment of COVID-19. Also, attention was paid to the side effects of the drug. CONCLUSIONS: According to the clinical results, it was found that remdesivir was effective in the treatment of COVID-19. The drug has side effects, but the symptoms were mild and disappeared immediately after discontinuation of medication.

[Correlation analysis between prostate imaging report and data system score and pathological results of prostate cancer].

Objective: To explore the correlation between prostate imaging report and data system (PI-RADS) score and international society of uological pathology (ISUP) grade of prostate cancer (PCa) and the role of PI-RADS score in predicting the pathological features of clinically significant PCa (csPCa), positive surgical margin and pathological upgrade. Methods: The pathologically positive patients with multi-parameter magnetic resonance image (mpMRI) were included in this study. The patients with prostate specific antigen (PSA)<100 µg/L were divided into two groups: biopsy group (n=523) and RP group (n=215). The correlation between PI-RADS score and ISUP grade and the accuracy of predicting csPCa in the two groups were evaluated. In the RP group, the correlation between PI-RADS score and postoperative pathological grade or degradation and positive incisal margin was further discussed. The patients with PSA≥100 µg/L (171cases in biopsy group and 6 cases in RP group) were not included in the statistical analysis, and the results were simply described. Results: The age, prostate volume, and PSA level of biopsy group and RP group was (72±8) years vs (68±7) years, 48.3 (32-57) cm(3) vs 47.2 (32-54) cm(3), and 26.3(10.2-34.2)µg/L vs 21.7 (9.24-23.95)µg/L, respectively. The PI-RADS scores ≤ 3,4, and 5 in the biopsy group were 109,97, and 317 respectively, and those in the RP group were 61,55, and 99 respectively. There were significant differences in the composition of ISUP grades of different PI-RADS scores between the two groups (P<0.001), and there was a positive correlation between the two groups (r=0.493 in the biopsy group, r=0.671 in the RP group, both P<0.001). Using PI-RADS score to predict csPCa, biopsy group (AUC=0.764, P<0.001, 95%CI:0.710-0.819) and RP group (AUC=0.807, P<0.001, 95%CI:0.735-0.879) had certain accuracy. The PI-RADS score combined with PSA could improve the accuracy of csPCa prediction in the biopsy group (AUC=0.795,P<0.001, 95% CI:0.746-0.843) and the RP group (AUC=0.852, P<0.001, 95%CI:0.789-0.915). Compared with the pathological results of biopsy in the RP group, 52.6% of the patients showed upgrade and degrade of ISUP, and there was insignificant difference in the composition of PI-RADS scores between upgraded and degraded patients (P>0.05). However, 41.7%(27/65) of the patients with ISUP grade 1 biopsies had pathological upgrades that the patients with PI-RADS ≤ 3 accounted for 33.3%, while the patients with PI-RADS>3 accounted for 66.7%, and there was significant difference between the two groups (P<0.05). After RP, 43.3% of the patients had positive surgical margins, and the patients with PI-RADS score ≤ 3, 4 and 5 were 13 (14%), 24 (25.8%) and 56 (60.2%), respectively, while the PI-RADS scores of patients with negative surgical margin were 48 (39.3%), 31(25.4%) and 43(35.2%), respectively. There was significant difference between the two groups (P<0.001). The higher the PI-RADS score, the greater the possibility of the positive surgical margin. For the patients with PSA ≥ 100 µg/L, 98.8% (169/171) patients in the biopsy group had a PI-RADS score 5. The pathological results of all patients were csPCa, of which 85.4% (146/171) had ISUP grade ≥ 4. Among them, 6 cases underwent RP, 5 cases had ISUP grade ≥ 4, all surgical margin were positive, 5 cases had seminal vesicle invasion, 3 cases had capsule invasion and 3 cases had positive pelvic lymph nodes. Conclusion: ThePI-RADS score is correlated with the ISUP grade of PCa. Combined with PSA can accurately predict csPCa. At the same time, the higher PI-RADS score, the more likely the patients with positive incisal margin after RP and Gleason score of 3+3=6 at the time of puncture will be upgraded pathologically.

[Effect of multimodal analgesia using periprostatic nerve block anesthesia combined with flurbiprofen in transperineal template-guided prostate biopsy].

Objective: To evaluate the effect of multimodal analgesia using periprostatic nerve block anesthesia (PNB) combined with flurbiprofen in patients undergoing transperineal template-guided prostate biopsy (TTPB). Methods: Totally 166 patients (aged (68.2±9.1) years, range: 47 to 81 years) who received TTPB from October 2017 to June 2018 at Department of Urology, Northern Jiangsu People's Hospital Affiliated to Yangzhou University were enrolled prospectively. All the patients were randomly divided into 2 groups. The observation group (n=79) was given flurbiprofen axetil 1 mg/kg intravenously for half an hour before operation and lidocaine was used for PNB before the biopsy. The control group (n=87) was given normal saline combined with PNB. A visual analog scale (VAS) and visual numeric scale (VNS) were used to assess the patients' pain and quantify their satisfaction at two time points: VAS-1 and VNS-1: during biopsy procedure, VAS-2 and VNS-2: 30 min after the procedure. The date were compared by t test, χ(2) test, Fisher exact test and two-way repeated measures anova analysis between the 2 groups. Results: The age, total prostate volume, serum prostate-specific antigen and the number of cores were comparable among the 2 groups (P>0.05). The VAS-1 scores of the control group and the observation group were 2.8±1.7, 1.9±1.2, respectively, and the VNS-1 were 3.1±0.7, 3.4±0.3, respectively. The VAS-1 were significantly lower in observation group than in control group (F=3.904, P=0.000). Conversely, the VNS-1 were higher in observation group (F=3.526, P=0.000). At 30-minute postoperative, the VAS-2 and VNS-2 were 0.7±0.4 and 3.7±0.2 in the control group, respectively. The VAS-2 and VNS-2 were 0.6±0.5 and 3.8±0.1 in the observation group, respectively. There were no significant differences in the pain scores or the satisfaction scores between the 2 groups (F=1.429, 2.825; P=0.136, 0.083). The incidence of overall complications was 26.4% (23/87) in the control group and 25.3% (20/79) in the observation group, with no statistical difference between the 2 groups (χ(2)=0.027, P=0.869). And the complications had no statistically significant difference among the 2 groups including hematuria, urinary retention, infection, hematospermia, vascular and neurological reactions, nausea, vomiting, dizziness, headache, and respiratory depression (P>0.05). Conclusion: The multimodal analgesia induced by PNB and flurbiprofen could effectively relieve the pain for patients who received TTPB.

[Effect of esmolol in septic shock patients with tachycardia: a randomized clinical trial].

Objective: To investigate the effect of esmolol in septic shock patients with tachycardia. Methods: A prospective randomized controlled trial was conducted. Screening septic shock patients that admitted to Department of General Intensive Care Unit of the First Affiliated Hospital of Zhengzhou University from June 2016 to August 2017. After 24 h resuscitation therapy, 100 cases of septic shock patients with tachycardia (heart rate>100 bpm) were divided into esmolol group (n=50) and control group (n=50) with random number table. Patients in esmolol group accepted standard treatment plus esmolol injection with an initial dose of 25 mg/h. Heart rate target is 80 to 100 bpm. Patients in esmolol group continued to use esmolol for 7 days or to the day the patient left the ICU when the heart rate didn't achieve the target. Patients in control group were given standard treatment. Primary outcome was 28 d mortality. Secondary outcomes included heart rate, norepinephrine dosages, lactate level, inflammatory markers in per day during the trial; acute physiology and chronic health evaluation (APACHE Ⅱ) and sequential organ failure assessment (SOFA) on day 1, 3, 5, 7; length of hospital stay, length of mechanical ventilation, medication time of vasoactive agent. The data were compared with t test or rank sum test between the two groups. Results: The 28 d mortality of esmolol group and control group was 62%, 68%, respectively(χ(2)=0.529, P=0.529). Logistic regression analysis showed that primary heart rate (increase of 10 bpm, OR=1.568, 95%CI: 1.039-1.238, P=0.027), primary APACHEⅡ (OR=1.134, 95%CI: 1.026-1.239, P=0.005), integral heart rate (per 10 bpm, OR=2.207, 95%CI: 1.400-3.479, P=0.001) were independent risk factors for 28 d mortality. Compared with control group, the esmolol group had a lower heart rate on day 1-7; but over all, there was no statistically significant difference in heart rate between the two groups (P>0.05). There was no significant difference in total does of norepinephrine, lactate level, inflammatory markers, APACHE Ⅱ, SOFA, length of hospital stay between the two groups (all P>0.05). Conclusion: Tachycardia significantly increases the risk of death in patients with septic shock, esmolol may decrease the mortality by controlling heart rate.

[Complications of transperineal template-guided prostate mapping biopsy].

Objective: To assess the complications of transperineal template-guided prostate mapping biopsy (TTMB). Methods: Between May 2017 and March 2018, 142 consecutive patients with prior negative transrectal biopsy results and persistently elevated prostate-specific antigen (PSA) were divided into the observation group and the control group randomly. The observation group underwent TTMB and the control group underwent transperineal template-guided prostate saturation biopsy (TTSB). Bleeding, infection, urinary function were recorded after prostate biopsy. Erectile function (ED) was measured at baseline, 1 month, 3 months and 6 months after prostate biopsy using the International Index of Erectile Function (IIEF-5). Results: A mean of 59 cores (from 33 to 116 cores) were obtained in TTMB, and a mean of 23 cores (from 11 to 44 cores) were obtained in TTSB. The positive rate was 50.0% (30/60) in TTMB, and 32.9% (27/82) in TTSB, and there were significant differences between two groups (P<0.05). The incidence of severe hematuria and urinary retention was 8.3% (5/60) and 11.7% (7/60) respectively in TTMB, while 1.2% (1/60) and 11.7% (7/60) respectively in TTSB. There were significant differences between two groups (P<0.05). But there were no significant differences between two groups in the incidence of mild, moderate and total hematuria, hematospermia, perineal hematoma, infection (P>0.05). Rectal bleeding was not observed. In TTMB group, the IIEF-5 scores at baseline, 1 month, 3 months and 6 months were (19.1±4.5), (17.4±4.8), (18.6±4.5), (19.0±4.0), respectively. In TTSB group, the IIEF-5 scores at baseline, 1 month, 3 months and 6 months were (19.7±4.3), (18.2±4.5), (19.1±4.1), (19.6±4.2), respectively. There were significant differences between baseline and 1 month after prostate biopsy in two groups (P<0.05), but there were no significant differences of IIEF-5 score between the two groups (P>0.05). Conclusions: TTMB can improve the positive rate for patients with prior negative transrectal biopsy results and persistently elevated PSA. TTMB has low complication rates, and most side-effects are self-limited. Compared with TTSB, the incidence of urinary retention and severe hematuria increases, but they can be recovered after clinical intervention. ED is transient, and affected for 1 month after the biopsy, but it will be recovered to the baseline after 3 to 6 months. Therefore, TTMB is a safe and reliable procedure.

[Thoracoscopy in diagnosis and treatment of pleural diseases in children].

Objective: To investigate the value of thoracoscopy in diagnosis and treatment of pleural diseases in children. Method: Clinical manifestations and treatment outcomes of 19 patients who had refractory pleural diseases treated with thoracosocy during May 2011 to August 2016 in Hunan Provincial People's Hospital were retrospectively analyzed. In 19 cases, 15 were male and 4 were female, with an average age of (4.8±2.0) years. Thirteen patients had left pleural lesion, while 5 patients had right lesion, and 1 had bilateral lesions. Result: All cases were successfully treated with thoracoscopy without emergent thoracotomy. Pre- and post operative diagnosis was compatible in 10 cases, including 8 cases of empyema (Streptococcus pneumoniae infection in 6 cases, and Staphylococcus Aureus infection in 2 cases), and 2 cases of tuberculous pleuritis. Nine patients who had not been clearly diagnosed before surgery were diagnosed to be empyema (4 case), tuberculous pleuritic (3 cases), mycoplasma infection (1 case), and foreign body with infection (1 case) by thoracoscopy. The average duration of post-op closed thoracic drainage was (4.7±2.3) days. The average time to get normal temperature was (2.4±2.6) days. And the average length of hospital stay was (6.7±1.8) days. No hemothorax, chylothorax, or need for analgesic occurred. Conclusion: Thoracoscopy can be recommended for diagnosis and treatment of refractory pleural lesions diseases in children, with minimal trauma and complications.

Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment.

This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2×10^{-4}≲|Δm_{41}^{2}|≲0.3 eV^{2} mass range. The resulting limits on sin^{2}2θ_{14} are improved by approx imately a factor of 2 over previous results and constitute the most stringent constraints to date in the |Δm_{41}^{2}|≲0.2 eV^{2} region.

Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments.

Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^{2}2θ_{µe} are set over 6 orders of magnitude in the sterile mass-squared splitting Δm_{41}^{2}. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm_{41}^{2}<0.8 eV^{2} at 95% CL_{s}.

[Effect of prostate volume on the peripheral nerve block anesthesia in prostate biopsy].

OBJECTIVE: To evaluate the anesthetic efficacy of periprostatic nerve block in transrectal ultrasound(TRUS) guided biopsy on different prostate volume. METHODS: A total of 568 patients received prostate biopsy in Department of Urology, Subei People's Hospital from May 2013 to September 2015 were retrospectively studied. All patients were divided into local anesthesia group and nerve block group according to different way of anesthesia. Then each group was divided into four subgroups(20-40 ml, >40-60 ml, >60-100 ml and >100 ml subgroups) according to different prostate volume range. After being anaesthetized successfully, patients in two groups underwent prostate biopsy, visual analogue scale(VAS) scores, visual numeric scale(VNS)scores and complications were recorded and analyzed. At inter-group and intra-group in local anesthesia group and nerve block group, Mann-Whitney U test of non-parametric analysis and single factor variance analysis were used to compare the VAS scores and the VNS scores respectively, and chi-square test was used to compare the rates of complication. RESULTS: The VAS scores of four subgroups: local anesthesia group: 1.9±0.9, 2.8±1.5, 3.8±2.3 and 5.3±2.5; nerve block group: 1.5±0.7, 2.0±0.8, 2.9±1.7 and 4.2±2.0. The VNS scores: local anesthesia group: 3.4±0.6, 2.9±0.6, 2.7±0.5 and 1.6±0.7; nerve block group: 3.7±0.5, 3.3±0.4, 3.0±0.8 and 2.0±0.7. The VAS scores and the VNS scores had significant differences (Z=-3.637-98.253, all P<0.05) at inter-group or intra-group level. For the complication rates of operation, hematuria, blood, urinary retention were significant differences (F=1.347-15.402, all P<0.05) at intra-group level. But there were no significant differences at inter-group level(P>0.05). CONCLUSION: Compared with local anesthesia, ultrasound guided prostate peripheral nerve block anesthesia has great analgesic effect and high safety, but for patients with a large prostate volumethe analgesic effect is inefficiency.

Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay.

This Letter reports a measurement of the flux and energy spectrum of electron antineutrinos from six 2.9 GWth nuclear reactors with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls in the Daya Bay experiment. Using 217 days of data, 296 721 and 41 589 inverse ß decay (IBD) candidates were detected in the near and far halls, respectively. The measured IBD yield is (1.55±0.04) ×10(-18) cm(2) GW(-1) day(-1) or (5.92±0.14) ×10(-43) cm(2) fission(-1). This flux measurement is consistent with previous short-baseline reactor antineutrino experiments and is 0.946±0.022 (0.991±0.023) relative to the flux predicted with the Huber-Mueller (ILL-Vogel) fissile antineutrino model. The measured IBD positron energy spectrum deviates from both spectral predictions by more than 2σ over the full energy range with a local significance of up to ∼4σ between 4-6 MeV. A reactor antineutrino spectrum of IBD reactions is extracted from the measured positron energy spectrum for model-independent predictions.

New measurement of antineutrino oscillation with the full detector configuration at Daya Bay.

We report a new measurement of electron antineutrino disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×10^{5} GW_{th} ton days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six ^{241}Am-^{13}C radioactive calibration sources reduced the background by a factor of 2 for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin^{2}2θ_{13} and |Δm_{ee}^{2}| were halved as a result of these improvements. An analysis of the relative antineutrino rates and energy spectra between detectors gave sin^{2}2θ_{13}=0.084±0.005 and |Δm_{ee}^{2}|=(2.42±0.11)×10^{-3} eV^{2} in the three-neutrino framework.

5-HMF prevents against oxidative injury via APE/Ref-1.

Oxidative injury is involved in many diseases, including ischemic and neurodegenerative diseases. Antioxidant drugs can be used to relieve the oxidative injury caused by these diseases; however, there are very few antioxidant drugs available for clinical use. In this study, we found that 5-(hydroxymethyl)-2-furfural (5-HMF) protects against the oxidative damage induced by cerebral ischemia in rats or by hydrogen peroxide (H2O2) in PC12 cells. We demonstrated that 5-HMF performs this function via apurinic/apyrimidinic endonuclease/redox factor-1 (APE/Ref-1). APE/Ref-1 is a multifunctional protein involved in oxidative DNA damage repair through the base excision repair (BER) pathway and in the regulation of the DNA-binding activity of several transcription factors. The current study focused on the role of APE/Ref-1 in the antioxidative properties of 5-HMF. The results show that 5-HMF inhibited the reduction of APE/Ref-1 protein level caused by cerebral ischemia-reperfusion injury in rats or H2O2 treatment in PC12 cells. Treatment with an APE/Ref-1 inhibitor blocked 5-HMF-induced protection, suggesting that APE/Ref-1's DNA repair function contributes to antioxidation. In conclusion, this study suggests that APE/Ref-1 may be a potential target for antioxidant drugs.

Radiation dose of non-enhanced chest CT can be reduced 40% by using iterative reconstruction in image space.

AIM: To evaluate the image quality and dose reduction capability of non-enhanced chest computed tomography (CT) examinations using iterative reconstruction in image space (IRIS). MATERIALS AND METHODS: A CT water phantom was scanned at 120 kV/150 mAs and 100 kV/270 mAs as the reference, and the tube current was decreased in 10% intervals down to 40% of the reference value. Image noise was evaluated and compared between filtered back-projection (FBP) and IRIS reconstructed data. In the patient study, 90 patients underwent non-enhanced chest CT examinations; the patients were randomly assigned into three groups: group A (n=30) standard dose protocol, 120 kV/110 mAs; group B (n=30) low dose, 100 kV/110 mAs; group C (n=30) low dose, 120 kV/67 mAs. All images were reconstructed by FBP and IRIS algorithm using matched kernels of B30 and I30. The objective image noise (OIN), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the aorta and latissimus dorsi were measured. The subjective image quality and noise were scored using a three-point scale by two experienced radiologists. The results of the subjective and objective image assessment were compared between groups B and C (low dose) IRIS and group A (standard dose) FBP. RESULTS: The phantom study showed comparable image noise between the scans using 60% dose with IRIS and 100% dose with FBP for both 120 and 100 kV. In the patient study, groups A, B, and C had effective dose of 3.81 ± 0.43, 2.40 ± 0.19, and 2.41 ± 0.15 mSv. IRIS significantly improved the OIN, SNR, and CNR compared with FBP for the same patient. The OIN, SNR, and CNR using IRIS in group B and C were improved or comparable to those in group A using FBP. No significant difference was found in subjective image quality and noise between groups B and C using IRIS and group A using FBP. CONCLUSION: Compared with FBP, IRIS can maintain or improve image quality on unenhanced chest CT image reconstruction while saving 40% radiation dose.

Adduction of DNA with MTBE and TBA in mice studied by accelerator mass spectrometry.

Methyl tert-butyl ether (MTBE) is a currently worldwide used octane enhancer substituting for lead alkyls and gasoline oxygenate. Our previous study using doubly (14)C-labeled MTBE [(CH(3))(3) (14)CO(14)CH(3)] has shown that MTBE binds DNA to form DNA adducts at low dose levels in mice. To elucidate the mechanism of the binding reaction, in this study, the DNA adducts with singly (14)C-labeled MTBE, which was synthesized from (14)C-methanol and tert-butyl alcohol (TBA), or (14)C-labeled TBA in mice have been measured by ultra sensitive accelerator mass spectrometry. The results show that the methyl group of MTBE and tert-butyl alcohol definitely form adducts with DNA in mouse liver, lung, and kidney. The methyl group of MTBE is the predominant binding part in liver, while the methyl group and the tert-butyl group give comparable contributions to the adduct formation in lung and kidney.