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• We report the first case of human Chlamydia pecorum pneumonia. • C. pecorum infection was identified by metagenomic next-generation sequencing and complement fixation test. • The patient was a farmer with diabetes and had close contact with sheep. • High fever, dry cough, and pulmonary consolidation are the main features. Chlamydia pecorum is a zoonotic pathogen. Here, we report the first case of human infection with C. pecorum. A man aged 51 years with high fever and dry cough was diagnosed with severe community-acquired pneumonia and respiratory failure. C. pecorum was found responsible for the infection, which was detected from bronchoalveolar lavage fluid through metagenomic next-generation sequencing. C. pecorum infection was further identified by quantitative polymerase chain reaction and complement fixation test. The patient's condition improved rapidly after targeted treatment. He was a farmer with diabetes mellitus and had a history of close contact with sheep, which might result in C. pecorum infection. Our report could provide a direction for the diagnosis and treatment of human C. pecorum pneumonia. [ABSTRACT FROM AUTHOR]

Background: Intraluminal thrombus (ILT) signal intensity on MRI has been studied as a potential marker of abdominal aortic aneurysm (AAA) progression.Purpose: 1) To characterize the relationship between ILT signal intensity and AAA diameter; 2) to evaluate ILT change over time; and 3) to assess the relationship between ILT features and AAA growth.Study Type: Prospective.Subjects: Eighty AAA patients were imaged, and a subset (n = 41) were followed with repeated MRI for 16 ± 9 months.Field Strength/sequence: 3D black-blood fast-spin-echo sequence at 3 T.Assessment: ILT was designated as "bright" if the signal was greater than 1.2 times that of adjacent psoas muscle. AAAs were divided into three groups based on ILT: Type 1: bright ILT; Type 2: isointense ILT; Type 3: no ILT. During follow-up, an active ILT change was defined as new ILT formation or an increase in ILT signal intensity to bright; stable ILT was defined as no change in ILT type or ILT became isointense from bright previously.Statistical Tests: Shapiro-Wilk test; Mann-Whitney U-test; Fisher's exact test; Kruskal-Wallis test; Spearman's r; intraclass correlation coefficient (ICC), Cohen's kappa.Results: AAAs with Type 1 ILT were larger than those with Types 2 and 3 ILT (5.1 ± 1.1 cm, 4.4 ± 0.9 cm, 4.2 ± 0.8 cm, P = 0.008). The growth rate of AAAs with Type 1 ILT was significantly greater than that of AAAs with Types 2 and 3 ILT (2.6 ± 2.5, 0.6 ± 1.3, 1.5 ± 0.6 mm/year, P = 0.01). During follow-up, AAAs with active ILT changes had a 3-fold increased growth rate compared with AAAs with stable ILT (3.6 ± 3.0 mm/year vs. 1.2 ± 1.5 mm/year, P = 0.008).Data Conclusion: AAAs with bright ILT are larger in diameter and grow faster. Active ILT change is associated with faster AAA growth. Black-blood MRI can characterize ILT features and monitor their change over time, which may provide new insights into AAA risk assessment.Level Of Evidence: 2 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2019;50:994-1001. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the clinical value of noise-based tube current reduction method with iterative reconstruction for obtaining consistent image quality with dose optimization in prospective electrocardiogram (ECG)-triggered coronary CT angiography (CCTA). Materials and Methods: We performed a prospective randomized study evaluating 338 patients undergoing CCTA with prospective ECG-triggering. Patients were randomly assigned to fixed tube current with filtered back projection (Group 1, n = 113), noise-based tube current with filtered back projection (Group 2, n = 109) or with iterative reconstruction (Group 3, n = 116). Tube voltage was fixed at 120 kV. Qualitative image quality was rated on a 5-point scale (1 = impaired, to 5 = excellent, with 3–5 defined as diagnostic). Image noise and signal intensity were measured; signal-to-noise ratio was calculated; radiation dose parameters were recorded. Statistical analyses included one-way analysis of variance, chi-square test, Kruskal-Wallis test and multivariable linear regression. Results: Image noise was maintained at the target value of 35HU with small interquartile range for Group 2 (35.00–35.03HU) and Group 3 (34.99–35.02HU), while from 28.73 to 37.87HU for Group 1. All images in the three groups were acceptable for diagnosis. A relative 20% and 51% reduction in effective dose for Group 2 (2.9 mSv) and Group 3 (1.8 mSv) were achieved compared with Group 1 (3.7 mSv). After adjustment for scan characteristics, iterative reconstruction was associated with 26% reduction in effective dose. Conclusion: Noise-based tube current reduction method with iterative reconstruction maintains image noise precisely at the desired level and achieves consistent image quality. Meanwhile, effective dose can be reduced by more than 50%. [ABSTRACT FROM AUTHOR]

Background: Fixed dose contrast medium (CM) injection protocols are often used in CT coronary arteriography (CTCA). However, vascular enhancement is related to body weight and injection dose rate. Purpose: To compare aortic enhancement and coronary imaging quality between a fixed dose CM injection protocol and one adapted to body weight with a constant injection dose rate in mg I/kg/s. Material and Methods: One hundred consecutive patients undergoing CTCA were randomized to two groups; group I received 65 mL CM (370 mg I/mL) at 5 mL/s and group II received 0.9 mL CM (370 mg I/mL) per kg during 12 s resulting in a constant injection dose rate of 28 mg I/kg/s.The groups were re-divided according to body weight: IA ≤ 70 kg, IB >70 kg, IIA ≤ 70 kg, IIB >70 kg. Aortic attenuation was measured and coronary imaging quality was graded using a four-grade scale. Results: The resulting mean CM dose, aortic attenuation and score of coronary imaging quality in groups IA/IB/IIA/IIB were 24/24/19/27 g I, 437/403/448/440 HU and 2.8/2.3/2.7/2.6, respectively. CM dose and aortic attenuation were significantly different between groups IA and IIA (p < 0.001, p = 0.01), as well as between groups IB and IIB (p < 0.001, p < 0.001).There was no statistically significant difference regarding coronary imaging quality between groups IA and IIA (p = 0.30), while there was a significant difference between groups IB and IIB (p < 0.001). Conclusion: In CTCA, body weight-adapted CM injection protocols using a constant dose rate can help save CM doses in slimmer patients and improve aortic enhancement and coronary imaging quality in heavier patients compared to fixed dose protocols. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To explore the feasibility of multiphase contrast–saline mixture with dual-flow injection technique for visualization of right ventricular (RV) cavity and interventricular septum (IVS) in 64-row multidetector computed tomography (MDCT) coronary angiography. Materials and methods: Twenty-four patients underwent coronary CT angiography (CTA) imaging with 64-row MDCT. In twelve patients (group A), 60ml contrast medium (CM) bolus was followed by 40ml saline, and in the other twelve patients (group B), 50ml CM bolus was followed by 50ml contrast–saline mixture at 60:40 ratio. The CM, saline and contrast–saline mixture flow rate were all 5.0ml/s. Two experienced radiologists measured the CT values of ascending aorta, descending aorta, pulmonary artery and RV, rated the uniformity of RV cavity, the visualization of coronary arteries and IVS independently. Results: By Kappa test, agreement between the two radiologists was 0.93 and 0.86 concerning the CT value measurements and the grades of the three indexes, respectively. By t-test, the mean CT values of ascending aorta and descending aorta of the two groups had no statistical difference (t =1.459, P >0.05; t =1.619, P >0.05); while the mean CT values of pulmonary artery and RV cavity had statistical differences (t =8.316, P <0.05; t =10.372, P <0.05). By two-related rank sum test, according to the visualization of coronary arteries and the uniformity of RV cavity, there were no statistical differences (U =66.00, P >0.05; U =54.00, P >0.05); while according to the visualization of IVS, group B was better than group A (U =8.00, P <0.05). Conclusion: In coronary CTA, a contrast–saline mixture after CM bolus can provide clear visualization of RV and IVS and LV without impairing coronary CTA image. [Copyright &y& Elsevier]

Purpose: This study aims to explore wall enhancement characteristics of vertebrobasilar nonsaccular aneurysms (VBNAs) and their relationship to clinical symptoms.Methods: We retrospectively analyzed VBNAs in the high resolution MR vessel wall imaging (HR-VWI) databases at two institutions. The aneurysmal basic characteristics and wall enhancement characteristics, were evaluated by two radiologists. The aneurysmal basic characteristics were location, type, the maximal outer diameter (Dmax), T1 hyperintensity, and mural thrombus. The wall enhancement characteristics included the presence or absence of enhancement, enhancement distribution (concentric or eccentric), enhancement grades (<50% & 50%), enhancement index ((SIwall-post/SIbrain-post- SIwall-pre/SIbrain-pre)/ (SIwall-pre/SIbrain-pre)), enhancement ratio (SIwall-post/SIpituitary-post), and enhancement extent (focal BA, whole BA, and VBA). The VBNAs' related symptoms of all cases were identified. The associations of aneurysmal basic characteristics and wall enhancement characteristics with symptoms were analyzed.Results: 34 VBNAs cases were included in the final analysis. Of the 34 cases, 18 cases (52.9%) presented VBNAs' related symptoms. Aneurysmal characteristics associated with symptoms were transitional type (P = 0.015), Dmax (P < 0.001), T1 hyperintensity (P = 0.003), mural thrombus (P < 0.001), the presence of enhancement (P = 0.003), enhancement index (P = 0.031), and enhancement ratio (P < 0.001). Aneurysmal characteristics that were independently associated with symptoms were Dmax (OR = 1.406, P = 0.013) and enhancement ratio (OR = 9.83, P = 0.037). In ROC curve analysis, AUC of the joint variable (Dmax and enhancement ratio) was 0.92, and the sensitivity and specificity were 94.4% and 87.5%, respectively.Conclusion: Wall enhancement correlates with symptomatic VBNAs. Dmax and enhancement ratio of aneurysmal wall are important indicators to instable status of symptomatic VBNAs. [ABSTRACT FROM AUTHOR]

Due to their vital physiological functions, nutritional fatty acids have great potential as nutraceutical food supplements for preventing an array of diseases such as inflammation, depression, arthritis, osteoporosis, diabetes and cancer. Microbial biosynthesis of fatty acids follows the trend of sustainable development, as it enables green, environmentally friendly and efficient production. As a natural oleaginous yeast, Yarrowia lipolytica is especially well-suited for the production of fatty acids. Moreover, it has a variety of genetic engineering tools and novel metabolic engineering strategies that make it a robust workhorse for the production of an array of value-added products. In this review, we summarize recent advances in metabolic engineering strategies for accumulating nutritional fatty acids in Y. lipolytica , including conjugated fatty acids and polyunsaturated fatty acids. In addition, the future prospects of nutritional fatty acid production using the Y. lipolytica platform are discussed in light of the current progress, challenges, and trends in this field. Finally, guidelines for future studies are also emphasized., Competing Interests: We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Engineering Yarrowia lipolytica to produce nutritional fatty acids: Current status and future perspectives”., (© 2022 The Authors.)

Background: Quantification of cardiac structure and function is essential for diagnostic interpretation and clinical decision making. We sought to establish cardiovascular magnetic resonance (CMR) reference values of left and right ventricular (LV and RV) morphology and function based on a large sample of healthy Chinese adults. Methods: Five hundred fifty validated healthy Chinese adults (aged 21-70 years; 323 men) free of hypertension, diabetes, and obesity were included in this study. All the subjects were stratified by gender (men and women) and age decades. On cine CMR, measurements of biventricular end-diastolic, end-systolic, and stroke volumes (EDV, ESV, and SV), ejection fraction (EF), and end-diastolic LV wall thickness (LVWT) and mass (LVM) were obtained. Results: Men had greater LVEDV (111.6 ± 19.8 vs. 94.6 ± 15.6 ml), LVESV (36.5 ± 9.8 vs. 28.2 ± 7.9 ml), LVM (121.1 ± 19.9 vs. 86.1 ± 14.5 g), global end-diastolic LVWT (8.1 ± 1.1 vs. 6.7 ± 1.0 mm), RVEDV (128.0 ± 23.6 vs. 101.7 ± 17.0 ml), and RVESV (53.5 ± 13.7 vs. 36.8 ± 8.9 ml), while women had greater LVEF (67.5 ± 5.4 vs. 70.4 ± 5.7%) and RVEF (58.5 ± 5.2 vs. 64.0 ± 5.3%) (all p < 0.001). For both men and women, age was negatively correlated with LVEDV ( r = -0.31 and r = -0.32), LVESV ( r = -0.37 and r = -0.47), RVEDV ( r = -0.31 and r = -0.29), and RVESV ( r = -0.33 and r = -0.44), while it was positively correlated with LVEF ( r = 0.28 and r = 0.43) and RVEF ( r = 0.28 and r = 0.41) (all p < 0.001). Aging was associated with increasing global end-diastolic LVWT and LVM/LVEDV in both sexes (all p < 0.001). Older age was associated with increasing LVM only in women ( r = 0.36, p < 0.001), not in men ( r = 0.05, p = 0.359). Conclusions: We systematically provide age-, sex-, and body size-specific CMR reference values for biventricular morphology and function based on a large sample of healthy Chinese adults. Biventricular structure and function are significantly associated with age and sex., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Ma, Gao, Cao, Zhu, Zhao, Zhao, Zeng, Lou, Pohost and Li.)