COVID-19 pneumonia: what has CT taught us? Lee, Elaine Y P; Ng, Ming-Yen; Khong, Pek-Lan
The Lancet infectious diseases,
04/2020, Letnik:
20, Številka:
4
Journal Article
Recenzirano
Odprti dostop
In late December, 2019, a cluster of cases of viral pneumonia was linked to a seafood market in Wuhan (Hubei, China), and was later determined to be caused by a novel coronavirus, severe acute ...respiratory syndrome coronavirus 2 (SARS-CoV-2; previously known as 2019-nCoV).1 The genome sequence of SARS-CoV-2 is similar to, but distinct from, those of two other coronaviruses responsible for large-scale outbreaks in the past: severe acute respiratory syndrome coronavirus (SARS-CoV; about 79% sequence identity) and Middle East respiratory syndrome coronavirus (MERS-CoV; about 50%).2 CT has been an important imaging modality in assisting in the diagnosis and management of patients with coronavirus disease 2019 (COVID-19) pneumonia, and reports on the radiological appearances of COVID-19 pneumonia are emerging. ...it is unclear whether the threshold for performing CT evaluation of potential lung changes should be lower when chest radiographs are normal. There is more to be learnt about this novel contagious viral pneumonia; more research is needed into the correlation of CT findings with clinical severity and progression, the predictive value of baseline CT or temporal changes for disease outcome, and the sequelae of acute lung injury induced by COVID-19.
Biomarker discovery and validation is a critical aim of the medical and scientific community. Research into exercise and diet-related biomarkers aims to improve health, performance, and recovery in ...military personnel, athletes, and lay persons. Exercise physiology research has identified individual biomarkers for assessing health, performance, and recovery during exercise training. However, there are few recommendations for biomarker panels for tracking changes in individuals participating in physical activity and exercise training programs. Our approach was to review the current literature and recommend a collection of validated biomarkers in key categories of health, performance, and recovery that could be used for this purpose. We determined that a comprehensive performance set of biomarkers should include key markers of (a) nutrition and metabolic health, (b) hydration status, (c) muscle status, (d) endurance performance, (e) injury status and risk, and (f) inflammation. Our review will help coaches, clinical sport professionals, researchers, and athletes better understand how to comprehensively monitor physiologic changes, as they design training cycles that elicit maximal improvements in performance while minimizing overtraining and injury risk.
A smart window is fabricated from a composite consisting of elastomeric poly(dimethylsiloxane) embedded with a thin layer of quasi‐amorphous silica nanoparticles. The smart window can be switched ...from the initial highly transparent state to opaqueness and displays angle‐independent structural color via mechanical stretching. The switchable optical property can be fully recovered after 1000 stretching/releasing cycles.
Objectives
The study aimed to compare the ability of morphological and texture features derived from contrast-enhanced CT in histological subtyping of epithelial ovarian carcinoma (EOC).
Methods
...Consecutive 205 patients with newly diagnosed EOC who underwent contrast-enhanced CT were included and dichotomised into high-grade serous carcinoma (HGSC) and non-HGSC. Clinical information including age and cancer antigen 125 (CA-125) was documented. The pre-treatment images were analysed using commercial software, TexRAD, by two independent radiologists. Eight qualitative CT morphological features were evaluated, and 36 CT texture features at 6 spatial scale factors (SSFs) were extracted per patient. Features’ reduction was based on kappa score, intra-class correlation coefficient (ICC), univariate ROC analysis and Pearson’s correlation test. Texture features with ICC ≥ 0.8 were compared by histological subtypes. Patients were randomly divided into training and testing sets by 8:2. Two random forest classifiers were determined and compared: model 1 incorporating selected morphological and clinical features and model 2 incorporating selected texture and clinical features.
Results
HGSC showed specifically higher texture features than non-HGSC (
p
< 0.05). Both models performed highly in predicting histological subtypes of EOC (model 1: AUC 0.891 and model 2: AUC 0.937), and no statistical significance was found between the two models (
p
= 0.464).
Conclusion
CT texture analysis provides objective and quantitative metrics on tumour characteristics with HGSC demonstrating specifically high texture features. The model incorporating texture analysis could classify histology subtypes of EOC with high accuracy and performed as well as morphological features.
Key Points
• A number of CT morphological and texture features showed good inter- and intra-observer agreements.
• High-grade serous ovarian carcinoma showed specifically higher CT texture features than non-high-grade serous ovarian carcinoma.
• CT texture analysis could differentiate histological subtypes of epithelial ovarian carcinoma with high accuracy.
Group I self-splicing ribozymes commonly function as components of selfish mobile genetic elements. We identified an allosteric group I ribozyme, wherein self-splicing is regulated by a distinct ...riboswitch class that senses the bacterial second messenger c-di-GMP. The tandem RNA sensory system resides in the 5' untranslated region of the messenger RNA for a putative virulence gene in the pathogenic bacterium Clostridium difficile. c-di-GMP binding by the riboswitch induces folding changes at atypical splice site junctions to modulate alternative RNA processing.Our findings indicate that some self-splicing ribozymes are not selfish elements but are harnessed by cells as metabolite sensors and genetic regulators.
Purpose
To describe and compare differences in peri-operative outcomes of robot-assisted (RA-RPLND) and open (O-RPLND) retroperitoneal lymph node dissection performed by a single surgeon where ...chemotherapy is the standard initial treatment for Stage 2 or greater non-seminomatous germ cell tumour.
Methods
Review of a prospective database of all RA-RPLNDs (28 patients) and O-RPLNDs (72 patients) performed by a single surgeon from 2014 to 2020. Peri-operative outcomes were compared for patients having RA-RPLND to all O-RPLNDs and a matched cohort of patients having O-RPLND (20 patients). Further comparison was performed between all patients in the RA-RPLND group (21 patients) and matched O-RPLND group (18 patients) who had previous chemotherapy. RA-RPLND was performed for patients suitable for a unilateral template dissection. O-RPLND was performed prior to the introduction of RA-RPLND and for patients not suitable for RA-RPLND after its introduction.
Results
RA-RPLND showed improved peri-operative outcomes compared to the matched cohort of O-RPLND—median blood loss (50 versus 400 ml,
p
< 0.00001), operative duration (150 versus 195 min,
p
= 0.023) length-of-stay (1 versus 5 days,
p
< 0.00001) and anejaculation (0 versus 4,
p
= 0.0249). There was no statistical difference in complication rates. RA-RPLND had lower median lymph node yields although not significant (9 versus 13,
p
= 0.070). These improved peri-operative outcomes were also seen in the post-chemotherapy RA-RPLND versus O-RPLND analysis. There were no tumour recurrences seen in either group with median follow-up of 36 months and 60 months, respectively.
Conclusions
Post-chemotherapy RA-RPLND may have decreased blood loss, operative duration, hospital length-of-stay and anejaculation rates in selected cases and should, therefore, be considered in selected patients. Differences in oncological outcomes require longer term follow-up.
Abstract Background Many successful ultra-endurance athletes have switched from a high-carbohydrate to a low-carbohydrate diet, but they have not previously been studied to determine the extent of ...metabolic adaptations. Methods Twenty elite ultra-marathoners and ironman distance triathletes performed a maximal graded exercise test and a 180 min submaximal run at 64% VO2 max on a treadmill to determine metabolic responses. One group habitually consumed a traditional high-carbohydrate (HC: n = 10 , %carbohydrate:protein:fat = 59:14:25) diet, and the other a low-carbohydrate (LC; n = 10 , 10:19:70) diet for an average of 20 months (range 9 to 36 months). Results Peak fat oxidation was 2.3-fold higher in the LC group (1.54 ± 0.18 vs 0.67 ± 0.14 g/min; P = 0.000 ) and it occurred at a higher percentage of VO2 max (70.3 ± 6.3 vs 54.9 ± 7.8%; P = 0.000 ). Mean fat oxidation during submaximal exercise was 59% higher in the LC group (1.21 ± 0.02 vs 0.76 ± 0.11 g/min; P = 0.000 ) corresponding to a greater relative contribution of fat (88 ± 2 vs 56 ± 8%; P = 0.000 ). Despite these marked differences in fuel use between LC and HC athletes, there were no significant differences in resting muscle glycogen and the level of depletion after 180 min of running (− 64% from pre-exercise) and 120 min of recovery (− 36% from pre-exercise). Conclusion Compared to highly trained ultra-endurance athletes consuming an HC diet, long-term keto-adaptation results in extraordinarily high rates of fat oxidation, whereas muscle glycogen utilization and repletion patterns during and after a 3 hour run are similar.
F-fluoro-deoxyglucose positron emission tomography with computed tomography (FDG PET/CT) has been employed to define radiotherapy targets using a threshold based on the standardised uptake value ...(SUV), and has been described for use in cervical cancer. The aim of this study was to evaluate the concordance between the metabolic tumour volume (MTV) measured on FDG PET/CT and the anatomical tumour volume (ATV) measured on T2-weighted magnetic resonance imaging (T2W-MRI); and compared with the functional tumour volume (FTV) measured on diffusion-weighted MRI (DW-MRI) in cervical cancer, taking the T2W-ATV as gold standard.
Consecutive newly diagnosed cervical cancer patients who underwent FDG PET/CT and DW-MRI were retrospectively reviewed from June 2013 to July 2017. Volumes of interest was inserted to the focal hypermetabolic activity corresponding to the cervical tumour on FDG PET/CT with automated tumour contouring and manual adjustment, based on SUV 20%-80% thresholds of the maximum SUV (SUVmax) to define the MTV
, with intervals of 5%. Tumour areas were manually delineated on T2W-MRI and multiplied by slice thickness to calculate the ATV. FTV were derived by manually delineating tumour area on ADC map, multiplied by the slice thickness to determine the FTV
. Diffusion restricted areas was extracted from b0 and ADC map using K-means clustering to determine the FTV
. The ATVs, FTVs and the MTVs at different thresholds were compared using the mean and correlated using Pearson's product-moment correlation.
Twenty-nine patients were evaluated (median age 52 years). Paired difference of mean between ATV and MTV was the closest and not statistically significant at MTV
(-2.9cm
, -5.2%, p = 0.301). This was less than the differences between ATV and FTV
(25.0cm
, 45.1%, p < 0.001) and FTV
(11.2cm
, 20.1%, p = 0.001). The correlation of MTV
with ATV was excellent (r = 0.968, p < 0.001) and better than that of the FTVs.
Our study demonstrated that MTV
was the only parameter investigated with no statistically significant difference with ATV, had the least absolute difference from ATV, and showed excellent positive correlation with ATV, suggesting its superiority as a functional imaging modality when compared with DW-MRI and supporting its use as a surrogate for ATV for radiotherapy tumour contouring.
Objectives
This study aims to investigate the blood–brain barrier (BBB) permeability of curcumin analogues with shortened linkers and their ability to protect against amyloid‐beta toxicity in a whole ...organism model.
Method
Four curcumin analogues were synthesized. These analogues and curcumin were evaluated for their BBB permeability in the parallel artificial membrane permeability assay. The transgenic Caenorhabditis elegansGMC101 that expresses human Aβ1–42 was treated with the compounds to evaluate their ability to delay Aβ‐induced paralysis. Expression of skn‐1mRNA was examined on nematodes treated with selected efficacious compounds. In vitro Aβ aggregation in the presence of the compounds was performed.
Key findings
The four analogues showed improved BBB permeability vs curcumin in the PAMPA with the hemi‐analogue C4 having the highest permeability coefficient. At 100 μm, analogues C1 and C4 as well as curcumin significantly prolonged the survival of the nematodes protecting against Aβ toxicity. However, only curcumin and C4 showed protection at lower concentrations. skn‐1mRNA was significantly elevated in nematodes treated with curcumin and C4 indicating SKN‐1/Nrf activation as a possible mode of action.
Conclusions
Analogue C4 provides a new lead for the development of a curcumin‐based compound for protection against Aβ toxicity with an improved BBB permeability.
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