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Polish Journal of Microbiology Sep 2021This study was conducted to develop a cheap, rapid, and accurate modified combined-disk test (mCDT) approach to detect and differentiate KPC and MBL carbapenemases among...
This study was conducted to develop a cheap, rapid, and accurate modified combined-disk test (mCDT) approach to detect and differentiate KPC and MBL carbapenemases among clinical carbapenem-resistant Enterobacterales (CRE) isolates and simultaneously distinguish them from carbapenem-susceptible Enterobacterales (CSE) isolates. A total of 163 CRE and 90 third-generation cephalosporin-resistant Enterobacterales isolates were tested using imipenem and meropenem disks and different concentrations of carbapenemase inhibitors. The optimal sensitivity and specificity for detecting KPC carbapenemase were 97.2% and 100%, respectively. The sensitivity and specificity for detecting MBL carbapenemase were 100% and 100% with imipenem or meropenem and carbapenemase inhibitors within six hours. The inhibitory zone diameter of 18 mm for imipenem or meropenem disks without inhibitor could distinguish CRE from CSE isolates. Therefore, this mCDT approach may be a useful tool in clinical laboratories to detect CRE isolates and differentiate KPC and MBL producers, which is beneficial for patient management and hospital infection prevention and control.
Topics: Bacterial Proteins; Bacteriological Techniques; Drug Resistance, Bacterial; Enterobacteriaceae; Enzyme Inhibitors; Imipenem; Meropenem; beta-Lactamases
PubMed: 34584532
DOI: 10.33073/pjm-2021-036 -
The Journal of Veterinary Medical... Feb 2022Canine degenerative myelopathy (DM) is a progressive neurodegenerative disease of the spinal cord. The diagnosis is based on the observation of clinical signs, genetic...
Canine degenerative myelopathy (DM) is a progressive neurodegenerative disease of the spinal cord. The diagnosis is based on the observation of clinical signs, genetic testing, and exclusion of other spinal cord diseases, and a definitive diagnosis of DM can only be confirmed by postmortem histopathological findings. The aim of this study was to investigate the diagnostic ability of diffusion tensor imaging (DTI) for DM. Eight DM-affected Pembroke Welsh Corgis, thirteen dogs with thoracolumbar intervertebral disk herniation (IVDH), and six healthy control dogs were included. All dogs were scanned using a 3.0-T MRI system. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were calculated for each intervertebral disk level slice between T8-T9 and L2-L3 intervertebral disk levels, and the entire area of the thoracolumbar spinal cord between T8-T9 and L2-L3 intervertebral disk levels (T8-L3 region). The ADC and FA values of the T8-L3 region were significantly lower in the DM group than in the IVDH group. The ADC values for the T8-L3 region had a moderate negative correlation with clinical duration (r= -0.723, P=0.043); however, the FA values of other intervertebral disk levels and T8-L3 region had no correlation with clinical durations. The measurement of DTI indices can be used to quantitatively assess neurodegeneration and may have diagnostic value for DM. In particular, the ADC value of the T8-L3 region may aid in making a non-invasive premortem diagnosis of DM.
Topics: Animals; Anisotropy; Diffusion Tensor Imaging; Dog Diseases; Dogs; Neurodegenerative Diseases; Spinal Cord; Spinal Cord Diseases
PubMed: 34897158
DOI: 10.1292/jvms.21-0370 -
Membranes Feb 2023A numerical study was conducted to investigate the effect of rotating patterned disks on the flow and permeate flux in a dynamic filtration (DF) system. The DF system...
A numerical study was conducted to investigate the effect of rotating patterned disks on the flow and permeate flux in a dynamic filtration (DF) system. The DF system consists of a rotating patterned disk and a stationary housing with a circular flat membrane. The feed flow is driven by the rotating disk with the angular velocity ranging from 200 to 1000 rpm and the applied pressure difference between inlet and outlet ports. Wheel-shaped patterns are engraved on the disk surfaces to add perturbation to the flow field and improve the permeate flux in the filtration system. Five disks with varying numbers of patterns were used in numerical simulations to examine the effects of the number of patterns and the angular velocity of the disk on the flow and permeate flux in the DF system. The flow characteristics are studied using the velocity profiles, the cross-sectional velocity vectors, the vortex structures, and the shear stress distribution. The wheel-shaped patterns shift the central core layer in the circumferential velocity profile towards the membrane, leading to higher shear stresses at the membrane and higher flux compared to a plain disk. When the number of patterns on the disk exceeded eight at a fixed Reynolds number, there were significant increases in wall shear stress and permeate flux compared to a plain disk filtration system with no pattern.
PubMed: 36984677
DOI: 10.3390/membranes13030291 -
PloS One 2023After percutaneous implantation of a cardiac occluder, a complex healing process leads to the device coverage within several months. An incomplete device coverage...
After percutaneous implantation of a cardiac occluder, a complex healing process leads to the device coverage within several months. An incomplete device coverage increases the risk of device related complications such as thrombosis or endocarditis. We aimed to assess the device coverage process of atrial septal defect (ASD) occluders in a chronic sheep model using micro-computed tomography (micro-CT). After percutaneous creation of an ASD, 8 ewes were implanted with a 16-mm Nit-Occlud ASD-R occluder (PFM medical, Cologne, Germany) and were followed for 1 month (N = 3) and 3 months (N = 5). After heart explant, the device coverage was assessed using micro-CT (resolution of 41.7 μm) and was compared to histological analysis. The micro-CT image reconstruction was performed in 2D and 3D allowing measurement of the coverage thickness and surface for each device. Macroscopic assessment of devices showed that the coverage was complete for the left-side disk in all cases. Yet incomplete coverage of the right-side disk was observed in 5 of the 8 cases. 2D and 3D micro-CT analysis allowed an accurate evaluation of device coverage of each disk and was overall well correlated to histology sections. Surface calculation from micro-CT images of the 8 cases showed that the median surface of coverage was 93±8% for the left-side disk and 55±31% for the right-side disk. The assessment of tissue reactions, including endothelialisation, after implantation of an ASD occluder can rely on in vitro micro-CT analysis. The translation to clinical practice is challenging but the potential for individual follow-up is shown, to avoid thrombotic or infective complications.
Topics: Female; Animals; Sheep; X-Ray Microtomography; Prosthesis Design; Treatment Outcome; Cardiac Catheterization; Heart Septal Defects, Atrial; Septal Occluder Device; Heart Atria
PubMed: 37093832
DOI: 10.1371/journal.pone.0284471 -
Current Opinion in Neurology Feb 2021Optic nerve head elevation can be associated with vision loss. This review provides an update regarding key features of optic disc drusen (ODD) compared with papilledema... (Review)
Review
PURPOSE OF REVIEW
Optic nerve head elevation can be associated with vision loss. This review provides an update regarding key features of optic disc drusen (ODD) compared with papilledema from increased intracranial pressure and optic disc edema from other causes.
RECENT FINDINGS
Clinical history and funduscopic examination are not sufficient to correctly diagnose different causes of optic nerve head elevation. Multimodal ophthalmic imaging is noninvasive and should be used as first-line diagnostic testing to distinguish optic disc edema or papilledema from pseudoedema. Advanced ophthalmic imaging, including enhanced depth imaging optical coherence tomography (EDI-OCT) and autofluorescence imaging, can visualize ODD at high resolution and determine whether there is optic disc edema. OCT angiography does not require contrast and can rapidly visualize papillary, peripapillary, and macular microvasculature and identify important vascular biomarker of ischemia and, potentially, visual prognosis.
SUMMARY
Multimodal ophthalmic imaging can help in the diagnosis of ODD and optic disc edema and identify patients at high risk of vision loss and neurological issues in order to ensure appropriate diagnosis and treatment.
Topics: Blindness; Diagnostic Techniques, Ophthalmological; Humans; Intracranial Hypertension; Multimodal Imaging; Ophthalmoscopy; Optic Disk; Optic Disk Drusen; Papilledema; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 33278141
DOI: 10.1097/WCO.0000000000000881 -
Gels (Basel, Switzerland) Apr 2022The rheology, i.e., the flow and deformation properties, of hydrogels is generally a very important consideration for their functionality. However, the accurate...
The rheology, i.e., the flow and deformation properties, of hydrogels is generally a very important consideration for their functionality. However, the accurate characterization of their rheological material functions is handicapped by their ubiquitous viscoplasticity and associated wall slip behavior. Here a parallel-disk viscometer was used to characterize the shear viscosity and wall slip behavior of a crosslinked poly(acrylic acid) (PAA) carbomer hydrogel (specifically Carbopol at 0.12% by weight in water). It was demonstrated that parallel-disk viscometry, i.e., the steady torsional flow in between two parallel disks, can be used to unambiguously determine the yield stress and other parameters of viscoplastic constitutive equations and wall slip behavior. It was specifically shown that torque versus rotational speed information, obtained from parallel-disk viscometry, was sufficient to determine the yield stress of a viscoplastic hydrogel. Additional gap-dependent data from parallel-disk viscometry could then be used to characterize the other parameters of the shear viscosity and wall slip behavior of the hydrogel. To investigate the accuracy of the parameters of shear viscosity and apparent wall slip that were determined, the data were used to calculate the torque values and the velocity distributions (using the lubrication assumption and parallel plate analogy) under different flow conditions. The calculated torques and velocity distributions of the hydrogel agreed very well with experimental data collected by Medina-Bañuelos et al., 2021, suggesting that the methodologies demonstrated here provide the means necessary to understand in detail the steady flow and deformation behavior of hydrogels. Such a detailed understanding of the viscoplastic nature and wall slip behavior of hydrogels can then be used to design and develop novel hydrogels with a wider range of applications in the medical and other industrial areas, and for finding optimum conditions for their processing and manufacturing.
PubMed: 35448131
DOI: 10.3390/gels8040230 -
Journal of Veterinary Internal Medicine Sep 2019Cervical spondylomyelopathy (CSM) occurs because of compression of the cervical spinal cord, nerve roots, or both, usually affecting young adult to older large and giant...
BACKGROUND
Cervical spondylomyelopathy (CSM) occurs because of compression of the cervical spinal cord, nerve roots, or both, usually affecting young adult to older large and giant breed dogs. Juvenile dogs are affected infrequently.
OBJECTIVE
To describe clinical and magnetic resonance imaging (MRI) findings in juvenile dogs (≤ 12 months) with cervical spondylomyelopathy.
ANIMALS
Twenty CSM-affected juvenile dogs.
METHODS
Medical and imaging records for juvenile dogs with CSM were reviewed. History and neurologic examination findings were obtained, including follow-up data. The MRI studies were reviewed for cause and site of spinal cord compression, intervertebral disk protrusion or degeneration, articular process degenerative changes, intervertebral foraminal stenosis, and spinal cord signal changes.
RESULTS
Mean (median) age at the time of diagnosis was 9.4 (10) months. There were 16 giant breed dogs. Eighteen dogs had a chronic presentation, 18/20 had proprioceptive ataxia, and 9/20 had cervical pain. On MRI, the principal spinal cord compression occurred at C5-C6, C6-C7, or both in most dogs; 12/20 dogs had ≥2 sites of spinal cord compression. The cause of compression was articular process proliferation in 8/20 dogs and disk protrusion in 2/20 dogs. Intervertebral disk degeneration was seen in 9/20 dogs. Follow-up was obtained for 12/20 dogs: 10/12 were managed medically and 2/12 surgically.
CONCLUSIONS AND CLINICAL IMPORTANCE
Cervical spondylomyelopathy in juvenile dogs was characterized mostly by osseous-associated spinal cord compression and multiple compressive sites. Almost half of the dogs had intervertebral disk degeneration. Intervertebral disk protrusion was seen in both giant and large breed dogs.
Topics: Animals; Cervical Vertebrae; Dog Diseases; Dogs; Female; Intervertebral Disc Degeneration; Intervertebral Disc Displacement; Magnetic Resonance Imaging; Male; Neck Pain; Spinal Cord Compression; Spinal Stenosis
PubMed: 31469206
DOI: 10.1111/jvim.15602 -
Bio-protocol Jun 2020Sarcomeres are extremely highly ordered macromolecular assemblies where proper structural organization is an absolute prerequisite to the functionality of these...
Sarcomeres are extremely highly ordered macromolecular assemblies where proper structural organization is an absolute prerequisite to the functionality of these contractile units. Despite the wealth of information collected, the exact spatial arrangement of many of the H-zone and Z-disk proteins remained unknown. Recently, we developed a powerful nanoscopic approach to localize the sarcomeric protein components with a resolution well below the diffraction limit. The ease of sample preparation and the near crystalline structure of the flight muscle sarcomeres make them ideally suitable for single molecule localization microscopy and structure averaging. Our approach allowed us to determine the position of dozens of H-zone and Z-disk proteins with a quasi-molecular, ~5-10 nm localization precision. The protocol described below provides an easy and reproducible method to prepare individual myofibrils for dSTORM imaging. In addition, it includes an in-depth description of a custom made and freely available software toolbox to process and quantitatively analyze the raw localization data.
PubMed: 33659324
DOI: 10.21769/BioProtoc.3654 -
Journal of Clinical Microbiology Sep 2020Clinical isolates of (= 554) were tested against fosfomycin using agar dilution, disk diffusion, and Etest. Agar dilution (reference method) identified few isolates...
Clinical isolates of (= 554) were tested against fosfomycin using agar dilution, disk diffusion, and Etest. Agar dilution (reference method) identified few isolates with fosfomycin MICs of 64 (= 3), 128 (= 4), and ≥256 μg/ml (= 2). Applying CLSI (M100, 2020) and EUCAST (v. 10.0, 2020) breakpoints, 98.9% and 98.4% (agar dilution), 99.3% and 99.1% (disk diffusion), and 99.1% and 98.9% (Etest) of isolates were fosfomycin susceptible, respectively. Essential agreement (agar dilution versus Etest) was low (40.8%); 59.3% (131/221) of isolates with agar dilution MICs of 2 to 128 μg/ml tested 2 to 4 doubling dilutions lower by Etest. Applying CLSI breakpoints, categorical agreement was >99% for both disk diffusion and Etest; no major errors (MEs) or very major errors (VMEs) were identified, and rates of minor errors (mEs) were <1%. EUCAST breakpoints yielded categorical agreements of >99% and no MEs for both disk diffusion and Etest; however, VMEs occurred at unacceptable rates of 44.4% (disk diffusion) and 33.3% (Etest). All isolates with agar dilution MICs of ≥32 μg/ml (= 12) and a subset of isolates with MICs of ≤16 μg/ml (= 49) were also tested using the Vitek 2 AST-N391 card and generated fosfomycin MICs 1 to ≥3 doubling dilutions lower than agar dilution for 11/12 isolates with agar dilution MICs of ≥32 μg/ml. We conclude that performing fosfomycin disk diffusion or Etest on urinary isolates of and interpreting results using CLSI breakpoints reliably identified fosfomycin-susceptible isolates regardless of differences in endpoint reading criteria. EUCAST breakpoints generated excessive rates of VMEs for our isolate collection of high fosfomycin susceptibility.
Topics: Anti-Bacterial Agents; Escherichia coli; Fosfomycin; Humans; In Vitro Techniques; Microbial Sensitivity Tests
PubMed: 32817224
DOI: 10.1128/JCM.01306-20 -
Skeletal Radiology Jul 2021To investigate the diagnostic accuracy of collagen-sensitive maps derived from dual-energy computed tomography (DECT) for the detection of lumbar disk pathologies in a...
OBJECTIVES
To investigate the diagnostic accuracy of collagen-sensitive maps derived from dual-energy computed tomography (DECT) for the detection of lumbar disk pathologies in a feasibility setting.
MATERIALS AND METHODS
We retrospectively reviewed magnetic resonance imaging (MRI), computed tomography (CT), and DECT datasets acquired in patients who underwent periradicular therapy of the lumbar spine from June to December 2019. Three readers scored DECT collagen maps, conventional CT, and MRI for presence, type, and extent of disk pathology. Contingency table analyses were performed to determine diagnostic accuracy using MRI as standard of reference. Interrater agreement within and between imaging modalities was evaluated by computing intraclass correlation coefficients (ICCs) and Cohen's kappa. Correlation between sum scores of anteroposterior disk displacement was determined by calculation of a paired t test.
RESULTS
In 21 disks in 13 patients, DECT had a sensitivity of 0.87 (0.60-0.98) and specificity of 1.00 (0.54-1.00) for the detection of disk pathology. Intermodality agreement for anteroposterior disk displacement was excellent for DECT (ICC 0.963 [0.909-0.985]) and superior to CT (ICC 0.876 [0.691-0.95]). For anteroposterior disk displacement, DECT also showed greater within-modality interrater agreement (ICC 0.820 [0.666-0.916]) compared with CT (ICC 0.624 [0.39-0.808]).
CONCLUSION
Our data suggest that collagen-sensitive imaging has an added benefit, allowing more accurate evaluation of the extent of disk displacement with higher interrater reliability. Thus, DECT could provide useful diagnostic information in patients undergoing CT for other indications or with contraindications to MRI.
Topics: Collagen; Humans; Lumbar Vertebrae; Magnetic Resonance Imaging; Reproducibility of Results; Retrospective Studies; Sensitivity and Specificity; Tomography, X-Ray Computed
PubMed: 33277674
DOI: 10.1007/s00256-020-03685-5