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Background Although the association of Helicobacter pylori (H. pylori) infection with diabetes mellitus has been evaluated, findings are controversial. This study investigated the association in a Chinese population. Methods A cross-sectional study, including a total of 30 810 subjects from the Dongfeng-Tongji Cohort study, was conducted. H. pylori status was measured via 14C urea breath test. Association analysis was performed by logistic regression, with multivariable adjustment for sex, age, body mass index, smoking, alcohol consumption, family history of diabetes, physical activity and the use of antibiotics. Results Among a middle-age and old-age Chinese population, individuals with H. pylori infection also had a higher prevalence of type 2 diabetes (21.3% versus 20.2%, p = 0.026). H. pylori infection was associated with higher risk of type 2 diabetes [odds ratio, 1.08 (95% confidence interval: 1.02–1.14); p = 0.008] after adjustment for other confounders. The association was significant among women, those who were above 65 years old, not overweight or obese, and those who did not smoke, did not consume alcohol and without family history of diabetes. However, there was no interaction between H. pylori infection and other traditional risk factors on type 2 diabetes risk. Subjects with H. pylori infection had a lower level of high-density lipoprotein cholesterol (p

BACKGROUND Epidemiological studies suggest that elevated serum uric acid (SUA) is associated with heightened incident kidney disease in both the general population and the type 2 diabetes (T2D) cases, although the results were not entirely consistent. METHODS We investigated prospective association between SUA levels and estimated glomerular filtration (eGFR) decline risk (eGFR

Supercritical fluid was used to extract volatile components from the rhizoma of Atractylode lancea (A. lancea). An orthogonal array design (OAD), L(9) (3)(4), was employed as a chemometric method for the optimization of the supercritical fluid extraction (SFE) of volatile compounds from the herbal medicine. Four parameters, namely, pressure, temperature, dynamic extraction time, and flow rate of CO(2), were studied and optimized by a three-level OAD in which the interactions between the parameters were neglected. These compounds were identified according to their retention times and mass spectra by GC-MS. A total of 30 compounds of SFE extracts were identified. Atractylon (8.63%), hinesol (1.44%), beta-eudesmol (6.64%), elemol (0.42%), and atractydin (13.92%) were the major sesquiterpenes identified in A. lancea SFE extracts.

Purpose: To accurately measure CT bow-tie profiles from various manufacturers and to provide non-proprietary information for CT system modeling. Methods: A GOS-based linear detector (0.8 mm per pixel and 51.2 cm in length) with a fast data sampling speed (0.24 ms/sample) was used to measure the relative profiles of bow-tie filters from a collection of eight CT scanners by three different vendors, GE (LS Xtra, LS VCT, Discovery HD750), Siemens (Sensation 64, Edge, Flash, Force), and Philips (iBrilliance 256). The linear detector was first calibrated for its energy response within typical CT beam quality ranges and compared with an ion chamber and analytical modeling (SPECTRA and TASMIP). A geometrical calibration process was developed to determine key parameters including the distance from the focal spot to the linear detector, the angular increment of the gantry at each data sampling, the location of the central x-ray on the linear detector, and the angular response of the detector pixel. Measurements were performed under axial-scan modes for most representative bow-tie filters and kV selections from each scanner. Bow-tie profiles were determined by re-binning the measured rotational data with an angular accuracy of 0.1 degree using the calibrated geometrical parameters. Results: The linear detector demonstrated an energy response as a solid state detector, which is close to the CT imaging detector. The geometrical calibration was proven to be sufficiently accurate ( 550 mm) and the bow-tie profiles measured from rotational mode matched closely to those from the gantry-stationary mode. Accurate profiles were determined for a total of 21 bow-tie filters and 83 filter/kV combinations from the abovementioned scanner models. Conclusion: A new improved approach of CT bow-tie measurement was proposed and accurate bow-tie profiles were provided for a broad list of CT scanner models.

Purpose: To compare size-specific dose estimate (SSDE) in abdominal fat quantitative CT with another dose estimate Dsize,L that also takes into account scan length. Methods: This study complied with the requirements of the Health Insurance Portability and Accountability Act. At our institution, abdominal fat CT is performed with scan length = 1 cm and CTDI vol = 4.66 mGy (referenced to body CTDI phantom). A previously developed CT simulation program was used to simulate single rotation axial scans of 6–55 cm diameter water cylinders, and dose integral of the longitudinal dose profile over the central 1 cm length was used to predict the dose at the center of one-cm scan range. SSDE and Dsize,L were assessed for 182 consecutive abdominal fat CT examinations with mean water-equivalent diameter (WED) of 27.8 cm ± 6.0 (range, 17.9 - 42.2 cm). Patient age ranged from 18 to 75 years, and weight ranged from 39 to 163 kg. Results: Mean SSDE was 6.37 mGy ± 1.33 (range, 3.67–8.95 mGy); mean Dsize,L was 2.99 mGy ± 0.85 (range, 1.48 - 4.88 mGy); and mean Dsize,L/SSDE ratio was 0.46 ± 0.04 (range, 0.40 - 0.55). Conclusion: The conversion factors for size-specific dose estimate in AAPM Report No. 204 were generated using 15 - 30 cm scan lengths. One needs to be cautious in applying SSDE to small length CT scans. For abdominal fat CT, SSDE was 80–150% higher than the dose of 1 cm scan length.

Purpose: To accurately measure the scatter radiation from a Hologic digital breast tomosynthesis (DBT) system and to provide updated scatter distribution to guide radiation shielding calculation for DBT rooms. Methods: A high sensitivity GOS-based linear detector was used to measure the angular distribution of scatter radiation from a Hologic Selenia Dimensions DBT system. The linear detector was calibrated for its energy response of typical DBT spectra. Following the NCRP147 approach, the measured scatter intensity was normalized by the primary beam area and primary air kerma at 1m from the scatter phantom center and presented as the scatter fraction. Direct comparison was made against Simpkin's initial measurement. Key parameters including the phantom size, primary beam area, and kV/anode/target combination were also studied. Results: The measured scatter-to-primary-ratio and scatter fraction data closely matched with previous data from Simpkin. The measured data demonstrated the unique nonisotropic distribution of the scattered radiation around a Hologic DBT system, with two strong peaks around 25° and 160°. The majority scatter radiation (>70%) originated from the imaging detector assembly, instead of the phantom. With a workload from a previous local survey, the scatter air kerma at 1m from the phantom center for wall/door is 0.018mGy/patient, for floor is 0.164mGy/patient, and for ceiling is 0.037mGy/patient. Conclusion: Comparing to Simpkin's previous data, the scatter air kerma from Holgoic DBT is at least two times higher. The main reasons include the harder primary beam with higher workload, added tomosynthesis acquisition, and strong small angle forward scattering. Due to the highly conservative initial assumptions, the shielding recommendation from NCRP147 is still sufficient for the Hologic DBT system given the workload from a previous local survey. With the data provided from this study, accurate shielding calculation can be performed for Hologic DBT systems with specific workload and barrier distance.

Purpose: To investigate how longitudinal dose profile DL(z) in 30 cm-diameter water cylinder change with tube current (mA) distribution and scan length. Methods: A constant and four variable mA distributions from two previous papers [Dixon et al., Med. Phys. 40, 111920 (14pp.) (2013); Zhang et al., Med. Phys. 41, 091911 (9pp.) (2014)] were adopted in three scan lengths of 10, 28.6, and 50 cm, and all mA distributions had the same average mA over scan ranges. Using the symmetry based dose calculation algorithms and the previously published CT dose equilibration data [Li et al., Med. Phys. 40, 031903 (10pp.) (2013); 41, 111910 (5pp.) (2014)], the authors calculated DL(z) on the phantom central and peripheral axes. Kolmogorov-Smirnov (K-S) test was used to compare the lineshapes of two arbitrary distributions. Results: In constant mA scans, DL(z) was “bell-shaped”. In variable mA scans, DL(z) approximately followed the mA lineshape, and the K-S distance generally changed with mA distribution. The distance decreased with scan length, and was larger on the central axis than on the peripheral axis. However, the opposite trends were found in the K-S distance between the DL(z) distributions of constant and variable mA distributions. Conclusion: Radiation dose from TCM scan is best evaluated using the specific tube current distribution. A constant mA based evaluation may lead to inconsistent longitudinal dose profile with that of TCM scan. Their difference in lineshape is larger on the phantom peripheral axis than on the central axis and increases with scan length. This work confirms that radiation dose in CT depends on not only local mA but also the overall mA distribution and scan length. On the other hand, the concept of regional tube current may be useful when scan length is large, tube current peaks near scan range edge, or the target site is superficial.