Objective To analyze the image noise and artifact of low-dose chest CT scanning and the distribution pattern. Methods A chest phantom equivalent to human tissue was scanned by 64 slices spiral scanner at standard dose (250 mAs) and low-dose (50, 30,and 21 mAs) respectively, HU in sites of the phantom and SD of which was recorded. 200 patients with pulmonary nodules were scanned at 30 or 21 mAs for minimal length. The relationship between severity of noise and artifact in chest low-dose CT scanning and gender or body mass index (BMI) of the patients, as well as the distribution of noise and artifact was evaluated. Results There was no statistical difference between the HU in sites of the phantom: lung (-777.3-- -758.2 HU, F=0.992, P<0.01), chest wall (107.9--111.3 HU, F=2.044, P>0.05), vertebra (835.6--875.3 HU, F=1.453, P>0.05), while the SD of which was of statistical signification: lung (9.5--29.0 HU, F=108.7, P<0.01), chest wall (10.1--32.4 HU, F=84.3, P<0.01), vertebra (19.2--57.1 HU, F=30.6, P<0.01),tbe SD increased with the decrease of the tube current. There was no statistical difference between male (in which 74 cases no or mild, 17 cases severe)and female (81 cases no or mild, and 28 cases severe)in image noise and artifact in low-dose images (X~2=2.294, P>0.05), and significant difference between groups of different BMI(in BMI<18.5 group, 29 cases no or mild,2 cases severe, in group of 18.5≤BMI<24.0, 120 cases no or mild, 13 cases severe, and in group of BMI≥24.0, 6 cases no or mild, 30 cases severe, X~2=128.274, P<0.01). The noise andartifact was greater in the upper (80 cases no or mild, 38 cases severe, X~2=18.918, P<0.01) and dorsal field (89 cases no or mild, 33 cases severe, X~2=6.760, P<0.05). Conclusions The image noise and artifact was significant in low-dose CT, especially in the dorsal and upper field of the lung, which might be attributed to the distribution of skeleton in the chest. It was recommended that scanning protocol (mAs value) be individualized adjusted in according to the patients BMI.

Objective To evaluate the sensitivity and optimized scanning parameter of 64-slice spiral CT in detection of pulmonary nodules with different size and density. Methods Three groups of prosthesis nodules with diameter of 2.5～13 mm and different density (soft-tissue, low density, and ground glass opacity,GGO)were taken into the chest phantom equivalent to human tissue,then scanned with Philips Brilliance 64 scanner in standard dose(tube voltage:120 kV, tube current: 250 mAs)and low-dose(tube voltage:120 kV, tube current: 50, 30,and 21mAs) respectively. The radiation dose(CTDIw and DLP) of the scans, Hounsfield unit(HU) and standard deviation(SD) of CT values in different regions of the phantom, and visibility of the nodules was assessed and recorded.Results The radiation dose of 64-slices spiral CT scanning in low-dose(tube current 21～51 mAs) decreased to 8%～20% of which scanning in standard-dose(250 mAs). There was no statistical difference between the CT values in different regions of the phantom (P>0.05), while the SD of CT values was of statistical significantce (P<0.001) and SD increased with the increment of the density under different scanning parameters. None of the nodules besides of GGO nodules with 2.5 mm and 4 mm in size scanned at 21 mAs was invisible. Conclusion GGO nodules of 2.5 mm in diameter can be detected with 64-slice spiral CT using 30 mAs at experimental study, which might be the optimized dose for detecting pulmonary nodules.

Objective To assess value of serum level of ischemia modified albumin (IMA) in diagnosis for myocardial ischemia of coronary artery disease (CAD). Methods Seventy-two patients with clinically suspected myocardial ischemia of CAD admitted to The First People's Hospital of Hangzhou during November 2009 to May 2010 ready for undergoing coronary angiography, the gold standard for diagnosis of CAD, were randomly selected for the study. The patients were divided into CAD and non-CAD groups based on their coronary angiography. Serum level of IMA was determined with cobalt-albumin binding ( ACB) assay before coronary angiography, which served as diagnostic standard for CAD. Logistic regression analysis method was used to evaluate varied levels of IMA with area under the receiver operating characteristic curve (AUCROC) in diagnosis for myocardial ischemia of CAD. Results Mean level of IMA was (97 ±24) U/ml and (81 ±15) U/ml for CAD group (n =51) and non-CAD group (n =21), respectively. Sensitivity and specificity of a cut-off value of IMA 83.69 U/ml in diagnosis for myocardial ischemia of CAD was 80 percent and 57 percent, respectively, with a predictive value of a positive test 82 percent and that of a negative test 55 percent, respectively, from AUCROC. Logistic regression analysis demonstrated that both hypertension (P=0. 022, 6 = 1.421, OR=4. 141) and level of IMA (P=0.003, b= 1.780, OR=5.928) were independent predictors for CAD. Conclusions Sensitivity, specificity and predictive value of a positive test of the level of IMA are relatively high in diagnosis for myocardial ischemia of CAD, which is an independent predictor of it.

In the past ten years, the research and application of microbiome has continued to increase. The microbiome has gradually become the research focus in the fields of life science, environmental science, and medicine. Meanwhile, many countries and organizations around the world are launching their own microbiome projects and conducting a multi-faceted layout, striving to gain a strategic position in this promising field. In addition, whether it is scientific research or industrial applications, there has been a climax of research and a wave of investment and financing, accordingly, products and services related to the microbiome are constantly emerging. However, due to the rapid development of microbiome sequencing and analysis related technologies and methods, the research and application from various countries have not yet unified on the standards of technology, programs, and data. Domestic industry participants also have insufficient understanding of the microbiome. New methods, technologies, and theories have not yet been fully accepted and used. In addition, some of the existing standards and guidelines are too general with poor practicality. This not only causes obstacles in the integration of scientific research data and waste of resources, but also gives related companies unfair competition opportunity. More importantly, China still lacks national standards related to the microbiome, and the national microbiome project is still in the process of preparation. In this context, the experts and practitioners of the microbiome worked together and developed the consensus of experts. It can not only guide domestic scientific research and industrial institutions to regulate the production, learning and research of the microbiome, the application can also provide reference technical basis for the relevant national functional departments, protect the scale and standardized corporate company's interests, strengthen industry self-discipline, avoid unregulated enterprises from disrupting the market, and ultimately promote the benign development of microbiome-related industries.
China ; Consensus ; Humans ; Industry ; Microbiota