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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]

• TR-MRA has high sensitivity and NPV for SAVSs and SDAVSs. • TR-MRA can correctly classify SAVSs. • For SDVASs, TR-MRA has high accuracy in the detection of feeding arteries. In comparison with the limited efficacy of conventional MR imaging and the invasiveness of catheter-based digital subtraction angiography (DSA), time-resolved MR angiography (TR-MRA) has been proposed as a promising examination for early diagnosis of spinal arteriovenous shunts (SAVSs). This paper aims to investigate the diagnostic performance of TR-MRA with scan parameters optimized for SAVSs evaluation in a large number of patients. One hundred patients with suspected SAVSs were enrolled. Each patient underwent preoperative TR-MRA with optimized scan parameters followed by DSA. The presence or absence of SAVS, the types and the angioarchitecture of SAVSs in the TR-MRA images were diagnostically analyzed. Among the final 97 patients, 80 cases (82.5 %) were diagnosed and classified by TR-MRA as spinal cord arteriovenous shunts (SCAVSs; n = 22), spinal dural arteriovenous shunts (SDAVSs; n = 48), and spinal extradural arteriovenous shunts (SEDAVSs; n = 10). The agreement for classifying SAVSs between TR-MRA and DSA was excellent (κ = 0.91). The sensitivity, specificity, PPV, NPV, and accuracy of TR-MRA for the diagnosis of SAVSs were 100 % (95 % CI, 94.3–100.0 %), 76.5 % (95 % CI, 49.8–92.2 %), 95.2 % (95 % CI, 87.6–98.5 %), 100 % (95 % CI, 71.7–100.0 %), and 95.9 % (95 % CI, 89.9–98.4 %). The accuracy rates of TR-MRA for the detection of feeding arteries were 75.9 %, 91.7 %, and 80.0 % for SCAVSs, SDAVSs, and SEDAVSs respectively. Time-resolved MR angiography showed excellent diagnostic performance for SAVSs screening. Additionally, this method can classify SAVSs and identify feeding arteries in SDAVSs with high diagnostic accuracy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fatty acid- and terpene-derived biofuels are ideal advanced transportation fuels. • Y. lipolytica is a valuable chassis for the overproduction of advanced biofuels. • Engineering Y. lipolytica to overproduce advanced biofuels is urgently needed. • Engineering strategies in Y. lipolytica for advanced biofuel overproduction are summarized. • Future perspectives in Y. lipolytica advanced biofuel production are prospected. Energy security and global climate change have necessitated the development of renewable energy with net-zero emissions. As alternatives to traditional fuels used in heavy-duty vehicles, advanced biofuels derived from fatty acids and terpenes have similar properties to current petroleum-based fuels, which makes them compatible with existing storage and transportation infrastructures. The fast development of metabolic engineering and synthetic biology has shown that microorganisms can be engineered to convert renewable feedstocks into these advanced biofuels. The oleaginous yeast Yarrowia lipolytica is rapidly emerging as a valuable chassis for the sustainable production of advanced biofuels derived from fatty acids and terpenes. Here, we provide a summary of the strategies developed in recent years for engineering Y. lipolytica to synthesize advanced biofuels. Finally, efficient biotechnological strategies for the production of these advanced biofuels and perspectives for future research are also discussed. [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]

Background: 3D non-contrast high-resolution black-blood cardiovascular magnetic resonance (CMR) (DANTE-SPACE) has been used for surveillance of abdominal aortic aneurysm (AAA) and validated against computed tomography (CT) angiography. However, it requires a long scan time of more than 7 min. We sought to develop an accelerated sequence applying compressed sensing (CS-DANTE-SPACE) and validate it in AAA patients undergoing surveillance. Methods: Thirty-eight AAA patients (all males, 73 ± 6 years) under clinical surveillance were recruited for this study. All patients were scanned with DANTE-SPACE (scan time 7:10 min) and CS-DANTE-SPACE (scan time 4:12 min, a reduction of 41.4%). Nine 9 patients were scanned more than 2 times. In total, 50 pairs of images were available for comparison. Two radiologists independently evaluated the image quality on a 1–4 scale, and measured the maximal diameter of AAA, the intra-luminal thrombus (ILT) and lumen area, ILT-to-muscle signal intensity ratio, and the ILT-to-lumen contrast ratio. The sharpness of the aneurysm inner/outer boundaries was quantified. Results: CS-DANTE-SPACE achieved comparable image quality compared with DANTE-SPACE (3.15 ± 0.67 vs. 3.03 ± 0.64, p = 0.06). There was excellent agreement between results from the two sequences for diameter/area and ILT ratio measurements (ICCs> 0.85), and for quantifying growth rate (3.3 ± 3.1 vs. 3.3 ± 3.4 mm/year, ICC = 0.95.) CS-DANTE-SPACE showed a higher ILT-to-lumen contrast ratio (p = 0.01) and higher sharpness than DANTE-SPACE (p = 0.002). Both sequences had excellent inter-reader reproducibility for quantitative measurements (ICC > 0.88). Conclusion: CS-DANTE-SPACE can reduce scan time while maintaining image quality for AAA imaging. It is a promising tool for the surveillance of patients with AAA disease in the clinical setting. [ABSTRACT FROM AUTHOR]

Background: As a noninvasive tool, myocardial deformation imaging may facilitate the early detection of cardiac dysfunction. However, normal reference ranges of myocardial strain and strain rate (SR) based on large-scale East Asian populations are still lacking. This study aimed to provide reference values of left ventricular (LV) and right ventricular (RV) strain and SR based on a large cohort of healthy Chinese adults using cardiovascular magnetic resonance (CMR) feature tracking (FT). Methods: Five hundred and sixty-six healthy Chinese adults (55.1% men) free of hypertension, diabetes, and obesity were included. On cine CMR, biventricular global radial, circumferential, and longitudinal strain (GRS, GCS, and GLS), and the peak radial, circumferential, and longitudinal systolic, and diastolic SRs (PSSRR, PSSRC, PSSRL, PDSRR, PDSRC, and PDSRL), and regional radial and circumferential strain at the basal, mid-cavity, and apical levels were measured. Associations of global and regional biventricular deformation indices with age and sex were investigated. Results: Women demonstrated greater magnitudes of LV GRS (37.6 ± 6.1% vs. 32.1 ± 5.3%), GCS (− 20.7 ± 1.9% vs. − 18.8 ± 1.9%), GLS (− 17.8 ± 1.8% vs. − 15.6 ± 1.8%), RV GRS (25.1 ± 7.8% vs. 22.1 ± 6.7%), GCS (− 14.4 ± 3.6% vs. − 13.2 ± 3.2%), GLS (− 22.4 ± 5.2% vs. − 20.2 ± 4.6%), and biventricular peak systolic and diastolic SR in all three coordinate directions (all P < 0.05). For the LV, aging was associated with increasing amplitudes of GRS, GCS, and decreasing amplitudes of PDSRR, PDSRC, PDSRL (all P < 0.05). For the RV, aging was associated with an increase in the magnitudes of GRS, GCS, GLS, PSSRR, PSSRC, PSSRL, and a decrease in the magnitude of PDSRR, PDSRC (all P < 0.05). Biventricular radial and circumferential strain measurements at the basal, mid-cavity, and apical levels were all significantly related to age and sex in both sexes (all P < 0.05). Conclusions: We provide age- and sex-specific normal values of biventricular strain and SR based on a large sample of healthy Chinese adults with a broad age range. These results may be served as a reference standard for cardiac function assessment, especially for the Chinese population. [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]

Abstract: Purpose: To investigate the potential of noise-based tube current reduction method with iterative reconstruction to reduce radiation exposure while achieving consistent image quality in coronary CT angiography (CCTA). Materials and methods: 294 patients underwent CCTA on a 64-detector row CT equipped with iterative reconstruction. 102 patients with fixed tube current were assigned to Group 1, which was used to establish noise-based tube current modulation formulas, where tube current was modulated by the noise of test bolus image. 192 patients with noise-based tube current were randomly assigned to Group 2 and Group 3. Filtered back projection was applied for Group 2 and iterative reconstruction for Group 3. Qualitative image quality was assessed with a 5 point score. Image noise, signal intensity, volume CT dose index, and dose-length product were measured. Results: The noise-based tube current modulation formulas were established through regression analysis using image noise measurements in Group 1. Image noise was precisely maintained at the target value of 35.00HU with small interquartile ranges for Group 2 (34.17–35.08HU) and Group 3 (34.34–35.03HU), while it was from 28.41 to 36.49HU for Group 1. All images in the three groups were acceptable for diagnosis. A relative 14% and 41% reduction in effective dose for Group 2 and Group 3 were observed compared with Group 1. Conclusion: Adequate image quality could be maintained at a desired and consistent noise level with overall 14% dose reduction using noise-based tube current reduction method. The use of iterative reconstruction further achieved approximately 40% reduction in effective dose. [Copyright &y& Elsevier]

Abstract: Purpose: The aim of this study was to investigate the clinical application value of right ventricle (RV) function measured by 64 multi-detector row CT (MDCT) in patients with chronic obstructive pulmonary disease (COPD) and cor pulmonale. Materials and methods: Sixty-three consecutive patients with COPD and cor pulmonale were referred for electrocardiographically gated MDCT for evaluation of suspected or known coronary artery disease. Magnetic resonance imaging (MRI) for cardiac function analysis was performed on the same day. The MDCT and MRI examinations were successfully completed in 58 patients. Forty-six patients with COPD were divided into three groups according to the severity of disease by the pulmonary function test (PFT). Twelve patients diagnosed as cor pulmonale and 32 control subjects were also included. The RV function and myocardial mass (MM) were obtained by 64-MDCT and 1.5T cardiac MRI in all of the groups. The results were compared among the groups using the Newman–Keuls method. Pearson''s correlation was used to evaluate the relationship between the right ventricular ejection fraction (RVEF) and MM with the PFT results in COPD and cor pulmonale patients. Results: The RVEF was significantly lower in patients with severe COPD and cor pulmonale than it was in those patients with mild or moderate COPD (P <0.01). There were strong correlations between MDCT and MRI (r =0.826 for RV MM, r =0.982 and 0.969 for RV EDV and RV ESV, r =0.899 for RVEF) and between MDCT results and forced expiratory volume in 1s (r =0.787 for RVEF, r =−0.774 for RV MM) in all patients. Conclusion: MDCT can accurately quantify RV function and MM. The RVEF and RV MM measured by MDCT correlate well with the severity of disease as determined by PFT in patients with COPD and cor pulmonale. The assessment of right ventricular function is clinically important for evaluation of the severity of COPD, which may provide an objective basis for therapeutic strategy. [Copyright &y& Elsevier]

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]

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), 60 ml contrast medium (CM) bolus was followed by 40 ml saline, and in the other twelve patients (group B), 50 ml CM bolus was followed by 50 ml contrast-saline mixture at 60:40 ratio. The CM, saline and contrast-saline mixture flow rate were all 5.0 ml/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. [ABSTRACT FROM AUTHOR]