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Journal of Cardiovascular... Apr 2022Ablation of papillary muscles (PMs) for refractory ventricular arrhythmias can often be challenging. The catheter approach and orientation during ablation may affect...
INTRODUCTION
Ablation of papillary muscles (PMs) for refractory ventricular arrhythmias can often be challenging. The catheter approach and orientation during ablation may affect optimal radiofrequency (RF) delivery. Yet, no previous study investigated the association between catheter orientation and PM lesion size. We evaluated ablation lesion characteristics with various catheter orientations relative to the PM tissue during open irrigated ablation, using a standardized, experimental setting.
METHODS
Viable bovine PM was positioned on a load cell in a circulating saline bath. RF ablation was performed over PM tissue at 50 W, with the open irrigated catheter positioned either perpendicular or parallel to the PM surface. Applied force was 10 g. Ablation lesions were sectioned and underwent quantitative morphometric analysis.
RESULTS
A catheter position oriented directly perpendicular to the PM tissue resulted in the largest ablation lesion volumes and depths compared with ablation with the catheter parallel to PM tissue (75.26 ± 8.40 mm vs. 34.04 ± 2.91 mm , p < .001) and (3.33 ± 0.18 mm vs. 2.24 ± 0.10 mm, p < .001), respectively. There were no significant differences in initial impedance, peak voltage, peak current, or overall decrease in impedance among groups. Parallel catheter orientation resulted in higher peak temperature (41.33 ± 0.28°C vs. 40.28 ± 0.24°C, p = .003), yet, there were no steam pops in either group.
CONCLUSION
For PM ablation, catheter orientation perpendicular to the PM tissue achieves more effective and larger ablation lesions, with greater lesion depth. This may have implications for the chosen ventricular access approach, the type of catheter used, consideration for remote navigation, and steerable sheaths.
Topics: Animals; Catheter Ablation; Catheters; Cattle; Heart Ventricles; Papillary Muscles; Therapeutic Irrigation
PubMed: 35133050
DOI: 10.1111/jce.15408 -
FEBS Letters Sep 2011DNA double-strand breaks (DSBs) represent the most destructive type of chromosomal lesion and trigger rapid chromatin restructuring accompanied by accumulation of... (Review)
Review
DNA double-strand breaks (DSBs) represent the most destructive type of chromosomal lesion and trigger rapid chromatin restructuring accompanied by accumulation of proteins in the vicinity of the DSB. Non-proteolytic ubiquitylation of chromatin surrounding DSBs, mediated by the RNF8/RNF168 ubiquitin ligase cascade, has emerged as a key mechanism for restoration of genome integrity by licensing the DSB-modified chromatin to concentrate genome caretaker proteins such as 53BP1 and BRCA1 near the lesions. In parallel, SUMOylation of upstream DSB regulators is also required for execution of this ubiquitin-dependent chromatin response, but its molecular basis is currently unclear. Here, we discuss recent insights into how ubiquitin- and SUMO-dependent signaling processes cooperate to orchestrate protein interactions with sites of DNA damage to facilitate DSB repair.
Topics: Chromatin; DNA Breaks, Double-Stranded; DNA Repair; DNA-Binding Proteins; Humans; Models, Genetic; Signal Transduction; Sumoylation; Ubiquitin; Ubiquitin-Protein Ligases
PubMed: 21664912
DOI: 10.1016/j.febslet.2011.05.056 -
European Radiology Oct 2020To characterize and interpret the CT imaging signs of the 2019 novel coronavirus (COVID-19) pneumonia in China.
OBJECTIVES
To characterize and interpret the CT imaging signs of the 2019 novel coronavirus (COVID-19) pneumonia in China.
MATERIALS AND METHODS
The CT images of 130 patients diagnosed as COVID-19 pneumonia from several hospitals in China were collected and their imaging features were analyzed and interpreted in detail.
RESULTS
Among the 130 patients, we can see (1) distribution: 14 cases with unilateral lung disease and 116 cases with bilateral disease, the distribution was mainly lobular core (99 cases) and subpleural (102 cases); (2) number: 9 cases with single lesion, 113 cases with multiple lesions, and 8 cases with diffuse distribution; (3) density: 70 cases of pure ground glass opacity (GGO), and 60 cases of GGO with consolidation; (4) accompanying signs: vascular thickening (100 cases), "parallel pleura sign" (98 cases), "paving stone sign" (100 cases), "halo sign" (18 cases), "reversed halo sign" (6 cases), pleural effusion (2 cases), and pneumonocele (2 cases). After follow-up CT examination on 35 patients, 21 cases turned better and 14 became worse. There were signs of consolidation with marginal contraction, bronchiectasis, subpleural line, or fibrous streak.
CONCLUSION
GGO and consolidation are the most common CT signs of COVID-19 pneumonia, mainly with lobular distribution and subpleural distribution. The main manifestations were tissue organization and fibrosis at late stage. The most valuable features are the parallel pleura sign and the paving stone sign.
KEY POINTS
• The CT signs of the COVID-19 pneumonia are mainly distributed in the lobular core, subpleural and diffused bilaterally. • The CT signs include the "parallel pleura sign," "paving stone sign," "halo sign," and "reversed halo sign." • During the follow-up, the distribution of lobular core, the fusion of lesions, and the organization changes at late stage will appear.
Topics: Adult; Betacoronavirus; COVID-19; China; Coronavirus Infections; Female; Humans; Lung; Male; Pandemics; Pneumonia, Viral; SARS-CoV-2; Tomography, X-Ray Computed
PubMed: 32367422
DOI: 10.1007/s00330-020-06915-5 -
Diagnostics (Basel, Switzerland) Jun 2023The development of automatic chest X-ray (CXR) disease classification algorithms is significant for diagnosing thoracic diseases. Owing to the characteristics of lesions...
The development of automatic chest X-ray (CXR) disease classification algorithms is significant for diagnosing thoracic diseases. Owing to the characteristics of lesions in CXR images, including high similarity in appearance of the disease, varied sizes, and different occurrence locations, most existing convolutional neural network-based methods have insufficient feature extraction for thoracic lesions and struggle to adapt to changes in lesion size and location. To address these issues, this study proposes a high-resolution classification network with dynamic convolution and coordinate attention (HRCC-Net). In the method, this study suggests a parallel multi-resolution network in which a high-resolution branch acquires essential detailed features of the lesion and multi-resolution feature swapping and fusion to obtain multiple receptive fields to extract complicated disease features adequately. Furthermore, this study proposes dynamic convolution to enhance the network's ability to represent multi-scale information to accommodate lesions of diverse scales. In addition, this study introduces a coordinate attention mechanism, which enables automatic focus on pathologically relevant regions and capturing the variations in lesion location. The proposed method is evaluated on ChestX-ray14 and CheXpert datasets. The average AUC (area under ROC curve) values reach 0.845 and 0.913, respectively, indicating this method's advantages compared with the currently available methods. Meanwhile, with its specificity and sensitivity to measure the performance of medical diagnostic systems, the network can improve diagnostic efficiency while reducing the rate of misdiagnosis. The proposed algorithm has great potential for thoracic disease diagnosis and treatment.
PubMed: 37443559
DOI: 10.3390/diagnostics13132165 -
European Journal of Orthodontics Sep 2023To evaluate the effect of high-fluoride mouth rinse and high-fluoride toothpaste on the development of demineralized lesions (DLs) during orthodontic treatment. (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To evaluate the effect of high-fluoride mouth rinse and high-fluoride toothpaste on the development of demineralized lesions (DLs) during orthodontic treatment.
TRIAL DESIGN
Three-armed parallel-group randomized controlled trial.
METHODS
The trial was performed with 270 adolescent orthodontic patients. Randomization was performed in blocks of 30, enrolling the patients into one of the following groups: the fluoride mouth rinse (FMR) group receiving 0.2% sodium fluoride (NaF) mouth rinse plus 1450 ppm fluoride (F) toothpaste; high-fluoride toothpaste (HFT) group receiving 5000 ppm F toothpaste; and the Control (CTR) group receiving 1450 ppm F toothpaste. Inclusion criteria were patients scheduled for treatment in both arches with fixed appliances and age between 12 and 20 years. The primary outcome variable was the proportion of participants with at least one new demineralized lesion as assessed on digital photos taken before and after treatment, analysed by a blinded clinician. The analysis included all teeth or teeth in the aesthetic zone, i.e. all central incisors, lateral incisors, and canines. A random sample of 30 participants was assessed to check intra- and inter-reliability. For pairwise comparison between groups, Fisher's non-parametric permutation test was used for continuous variables. Blinding was employed during the caries registration and data analysis.
RECRUITMENT
October 2010 to December 2012.
RESULTS
In total, 270 patients were randomized, of which 22 were excluded during treatment. Therefore, 248 participants were included in the study. The number of patients with an increase of ≥1 DL, including only central- and lateral incisors and canines, during orthodontic treatment, was significantly lower in the HFT group, 51/85 60%, compared to the CTR group, 64/82 78%, RR 0.77 (CI 0.62; 0.95), P = .01 and in the FMR group, 47/81 58%, compared to the CTR group, RR 0.74 (CI 0.60; 0.92), P < .01.
CONCLUSIONS
To prevent demineralized lesions in the aesthetic zone, high-fluoride mouth rinse and high-fluoride toothpaste may be recommended.
LIMITATIONS
The protocol was not registered, and the present study did not use a double-blinded design.
Topics: Adolescent; Humans; Child; Young Adult; Adult; Fluorides; Toothpastes; Mouthwashes; Reproducibility of Results; Esthetics, Dental; Dental Caries; Sodium Fluoride; Cariostatic Agents
PubMed: 37524332
DOI: 10.1093/ejo/cjad044 -
Neurobiology of Language (Cambridge,... 2023Sentence structure, or syntax, is potentially a uniquely creative aspect of the human mind. Neuropsychological experiments in the 1970s suggested parallel syntactic...
Sentence structure, or syntax, is potentially a uniquely creative aspect of the human mind. Neuropsychological experiments in the 1970s suggested parallel syntactic production and comprehension deficits in agrammatic Broca's aphasia, thought to result from damage to syntactic mechanisms in Broca's area in the left frontal lobe. This hypothesis was sometimes termed , converging with developments in linguistic theory concerning central syntactic mechanisms supporting language production and comprehension. However, the evidence supporting an association among receptive syntactic deficits, expressive agrammatism, and damage to frontal cortex is equivocal. In addition, the relationship among a distinct grammatical production deficit in aphasia, paragrammatism, and receptive syntax has not been assessed. We used lesion-symptom mapping in three partially overlapping groups of left-hemisphere stroke patients to investigate these issues: grammatical production deficits in a primary group of 53 subjects and syntactic comprehension in larger sample sizes ( = 130, 218) that overlapped with the primary group. Paragrammatic production deficits were significantly associated with multiple analyses of syntactic comprehension, particularly when incorporating lesion volume as a covariate, but agrammatic production deficits were not. The lesion correlates of impaired performance of syntactic comprehension were significantly associated with damage to temporal lobe regions, which were also implicated in paragrammatism, but not with the inferior and middle frontal regions implicated in expressive agrammatism. Our results provide strong evidence against the overarching agrammatism hypothesis. By contrast, our results suggest the possibility of an alternative grammatical parallelism hypothesis rooted in paragrammatism and a central syntactic system in the posterior temporal lobe.
PubMed: 37946730
DOI: 10.1162/nol_a_00117 -
NeuroImage Aug 2021White matter lesions are a very common finding on MRI in older adults and their presence increases the risk of stroke and dementia. Accurate and computationally... (Comparative Study)
Comparative Study
OBJECTIVES
White matter lesions are a very common finding on MRI in older adults and their presence increases the risk of stroke and dementia. Accurate and computationally efficient modelling methods are necessary to map the association of lesion incidence with risk factors, such as hypertension. However, there is no consensus in the brain mapping literature whether a voxel-wise modelling approach is better for binary lesion data than a more computationally intensive spatial modelling approach that accounts for voxel dependence.
METHODS
We review three regression approaches for modelling binary lesion masks including mass-univariate probit regression modelling with either maximum likelihood estimates, or mean bias-reduced estimates, and spatial Bayesian modelling, where the regression coefficients have a conditional autoregressive model prior to account for local spatial dependence. We design a novel simulation framework of artificial lesion maps to compare the three alternative lesion mapping methods. The age effect on lesion probability estimated from a reference data set (13,680 individuals from the UK Biobank) is used to simulate a realistic voxel-wise distribution of lesions across age. To mimic the real features of lesion masks, we propose matching brain lesion summaries (total lesion volume, average lesion size and lesion count) across the reference data set and the simulated data sets. Thus, we allow for a fair comparison between the modelling approaches, under a realistic simulation setting.
RESULTS
Our findings suggest that bias-reduced estimates for voxel-wise binary-response generalized linear models (GLMs) overcome the drawbacks of infinite and biased maximum likelihood estimates and scale well for large data sets because voxel-wise estimation can be performed in parallel across voxels. Contrary to the assumption of spatial dependence being key in lesion mapping, our results show that voxel-wise bias-reduction and spatial modelling result in largely similar estimates.
CONCLUSIONS
Bias-reduced estimates for voxel-wise GLMs are not only accurate but also computationally efficient, which will become increasingly important as more biobank-scale neuroimaging data sets become available.
Topics: Computer Simulation; Humans; Image Processing, Computer-Assisted; Models, Theoretical; Neuroimaging; White Matter
PubMed: 33895308
DOI: 10.1016/j.neuroimage.2021.118090 -
Brain Communications 2022The impact of vascular lesions on cognition is location dependent. Here, we assessed the contribution of small vessel disease lesions in the corpus callosum to vascular...
The impact of vascular lesions on cognition is location dependent. Here, we assessed the contribution of small vessel disease lesions in the corpus callosum to vascular cognitive impairment in cerebral amyloid angiopathy, as a model for cerebral small vessel disease. Sixty-five patients with probable cerebral amyloid angiopathy underwent 3T magnetic resonance imaging, including a diffusion tensor imaging scan, and neuropsychological testing. Microstructural white-matter integrity was quantified by fractional anisotropy and mean diffusivity. -scores on individual neuropsychological tests were averaged into five cognitive domains: information processing speed, executive functioning, memory, language and visuospatial ability. Corpus callosum lesions were defined as haemorrhagic (microbleeds or larger bleeds) or ischaemic (microinfarcts, larger infarcts and diffuse fluid-attenuated inversion recovery hyperintensities). Associations between corpus callosum lesion presence, microstructural white-matter integrity and cognitive performance were examined with multiple regression models. The prevalence of corpus callosum lesions was confirmed in an independent cohort of memory clinic patients with and without cerebral amyloid angiopathy ( = 82). In parallel, we assessed corpus callosum lesions on magnetic resonance imaging in cerebral amyloid angiopathy patients ( = 19) and controls ( = 5) and determined associated tissue abnormalities with histopathology. A total number of 21 corpus callosum lesions was found in 19/65 (29%) cerebral amyloid angiopathy patients. Corpus callosum lesion presence was associated with reduced microstructural white-matter integrity within the corpus callosum and in the whole-brain white matter. Patients with corpus callosum lesions performed significantly worse on all cognitive domains except language, compared with those without corpus callosum lesions after correcting for age, sex, education and time between magnetic resonance imaging and neuropsychological assessment. This association was independent of the presence of intracerebral haemorrhage, whole-brain fractional anisotropy and mean diffusivity, and white-matter hyperintensity volume and brain volume for the domains of information processing speed and executive functioning. In the memory clinic patient cohort, corpus callosum lesions were present in 14/54 (26%) patients with probable and 2/8 (25%) patients with possible cerebral amyloid angiopathy, and in 3/20 (15%) patients without cerebral amyloid angiopathy. In the cohort, corpus callosum lesions were present in 10/19 (53%) patients and 2/5 (40%) controls. On histopathology, ischaemic corpus callosum lesions were associated with tissue loss and demyelination, which extended beyond the lesion core. Together, these data suggest that corpus callosum lesions are a frequent finding in cerebral amyloid angiopathy, and that they independently contribute to cognitive impairment through strategic microstructural disruption of white-matter tracts.
PubMed: 35611313
DOI: 10.1093/braincomms/fcac105 -
Acta Neuropathologica Communications Nov 2020Sanfilippo syndrome is an untreatable form of childhood-onset dementia. Whilst several therapeutic strategies are being evaluated in human clinical trials including i.v....
Sanfilippo syndrome is an untreatable form of childhood-onset dementia. Whilst several therapeutic strategies are being evaluated in human clinical trials including i.v. delivery of AAV9-based gene therapy, an urgent unmet need is the availability of non-invasive, quantitative measures of neurodegeneration. We hypothesise that as part of the central nervous system, the retina may provide a window through which to 'visualise' degenerative lesions in brain and amelioration of them following treatment. This is reliant on the age of onset and the rate of disease progression being equivalent in retina and brain. For the first time we have assessed in parallel, the nature, age of onset and rate of retinal and brain degeneration in a mouse model of Sanfilippo syndrome. Significant accumulation of heparan sulphate and expansion of the endo/lysosomal system was observed in both retina and brain pre-symptomatically (by 3 weeks of age). Robust and early activation of micro- and macroglia was also observed in both tissues. There was substantial thinning of retina and loss of rod and cone photoreceptors by ~ 12 weeks of age, a time at which cognitive symptoms are noted. Intravenous delivery of a clinically relevant AAV9-human sulphamidase vector to neonatal mice prevented disease lesion appearance in retina and most areas of brain when assessed 6 weeks later. Collectively, the findings highlight the previously unrecognised early and significant involvement of retina in the Sanfilippo disease process, lesions that are preventable by neonatal treatment with AAV9-sulphamidase. Critically, our data demonstrate for the first time that the advancement of retinal disease parallels that occurring in brain in Sanfilippo syndrome, thus retina may provide an easily accessible neural tissue via which brain disease development and its amelioration with treatment can be monitored.
Topics: Animals; Asymptomatic Diseases; Brain; Disease Models, Animal; Endosomes; Genetic Therapy; Heparitin Sulfate; Humans; Hydrolases; Lysosomes; Mice; Microglia; Mucopolysaccharidosis III; Neurodegenerative Diseases; Retina; Retinal Cone Photoreceptor Cells; Retinal Degeneration; Retinal Rod Photoreceptor Cells
PubMed: 33203474
DOI: 10.1186/s40478-020-01070-w -
Endoscopy Jun 2023Previous studies have reported the effectiveness of narrow-band imaging (NBI) and linked-color imaging (LCI) in improving the detection of colorectal neoplasms. There... (Randomized Controlled Trial)
Randomized Controlled Trial Clinical Trial
BACKGROUND
Previous studies have reported the effectiveness of narrow-band imaging (NBI) and linked-color imaging (LCI) in improving the detection of colorectal neoplasms. There has however been no direct comparison between LCI and NBI in the detection of colorectal sessile serrated lesions (SSLs). The present study aimed to compare the effectiveness of LCI and NBI in detecting colorectal SSLs.
METHODS
A prospective, parallel, randomized controlled trial was conducted. The participants were randomly assigned to the LCI or NBI arms. The primary end point was the SSL detection rate (SDR).
RESULTS
406 patients were involved; 204 in the LCI arm and 202 in the NBI arm. The total polyp detection rate, adenoma detection rate, and SDR were 54.2 %, 38.7 %, and 10.8%, respectively. The SDR was not significantly different between the LCI and NBI arms (12.3 % vs. 9.4 %; = 0.36). The differences in the detection rate and the per-patient number of polyps, adenomas, diminutive lesions, and flat lesions between LCI and NBI also were not statistically significant. Multivariate analysis showed that LCI and NBI were not independent factors associated with SDR, whereas Boston Bowel Preparation Scale score (odds ratio [OR] 1.35, 95 %CI 1.03-1.76; = 0.03), withdrawal time (OR 1.13, 95 %CI 1.00-1.26; = 0.04), and operator experience (OR 3.73, 95 %CI 1.67-8.32; = 0.001) were independent factors associated with SDR.
CONCLUSIONS
LCI and NBI are comparable for SSL detection, as well as for the detection of polyps and adenomas.
Topics: Humans; Colonic Polyps; Colonoscopy; Prospective Studies; Colorectal Neoplasms; Narrow Band Imaging; Adenoma
PubMed: 36482165
DOI: 10.1055/a-1995-2685