-
Cureus Mar 2022Introduction Methicillin-resistant Staphylococcus aureus (MRSA) is associated with high morbidity and mortality due to the development of antimicrobial resistance...
Introduction Methicillin-resistant Staphylococcus aureus (MRSA) is associated with high morbidity and mortality due to the development of antimicrobial resistance secondary to irrational use of antibiotics, nonadherence to infection control practices, and increased use of intravascular devices in healthcare systems. Detection of MRSA is critical in clinical microbiology laboratories as it helps identify MRSA carriers and avoid treatment failure in patients. Hence, this study compared various phenotypic methods with the standard genotyping method to determine a method that permits rapid and accurate detection of MRSA. Materials & Methods () was initially identified based on colony morphology, Gram staining, standard biochemical tests, and antibiotic susceptibility using disk diffusion. MRSA was identified based on the detection of the mecA gene by polymerase chain reaction (PCR) and subsequent gel electrophoresis. Disk diffusion using cefoxitin or oxacillin and mannitol salt agar with 6-µg/ml oxacillin were used for phenotypic detection of MRSA. The D test was used to detect inducible clindamycin resistance in isolates. Results Of the 100 isolates analyzed, 37% were identified as MRSA by PCR and the cefoxitin disk diffusion method; however, only 31% were detected by the oxacillin disk diffusion method and 29% by the mannitol salt agar method. The sensitivity of the cefoxitin disk diffusion test, oxacillin disk diffusion, and mannitol salt agar methods was 86.05%, 83.78%, and 70.73%, respectively. Specificity was 100% for all the three phenotypic methods (p < 0.001). Notably, inducible clindamycin resistance was found in 37.2% of the MRSA isolates, indicating potential challenges in treatment. Conclusion Among the three phenotypic methods tested, the cefoxitin disk diffusion method had 100% sensitivity and specificity, which is similar to that of PCR-based MRSA detection. Hence, the cefoxitin disk diffusion method is recommended for use in clinical laboratories, where molecular methods are not available as it is both cost-effective and easy to perform.
PubMed: 35481290
DOI: 10.7759/cureus.23396 -
Indian Journal of Ophthalmology Mar 2023: "Congenital cavitary optic disk anomalies" is a term used to include optic disk pit (ODP), optic disk coloboma, and morning glory disk anomaly (MGDA). Imaging the...
BACKGROUND AND PURPOSE
: "Congenital cavitary optic disk anomalies" is a term used to include optic disk pit (ODP), optic disk coloboma, and morning glory disk anomaly (MGDA). Imaging the radial peripapillary capillary (RPC) network in congenital optic disk anomalies with optical coherence tomography-angiography (OCTA) can shed light on its pathogenesis. This video describes the OCTA findings of optic nerve head and RPC network using the angio-disk mode in five cases of congenital cavitary optic disk anomalies.
SYNOPSIS
The video presents characteristic RPC network alterations in two eyes of ODP, one eye of optic disk coloboma, and two eyes of noncontractile MGDA.
HIGHLIGHTS
OCTA in ODP and coloboma shows absence of RPC microvascular network and a region of capillary dropout. This finding is in contrast to MGDA, where the microvascular network is dense. OCTA is an effective imaging modality to study vascular plexus and RPC and their alteration in congenital disk anomalies, which could provide information about the structural differences among them.
VIDEO LINK
https://youtu.be/TyZOzpG4X4U.
Topics: Humans; Optic Disk; Coloboma; Eye Abnormalities
PubMed: 36872758
DOI: 10.4103/IJO.IJO_2743_22 -
PloS One 2022When animals are previously exposed to two different visual stimuli simultaneously, their learning performance at discriminating those stimuli delays: such a phenomenon...
When animals are previously exposed to two different visual stimuli simultaneously, their learning performance at discriminating those stimuli delays: such a phenomenon is known as "classifying-together" or "Bateson effect". However, the consistency of this phenomenon has not been wholly endorsed, especially considering the evidence collected in several vertebrates. The current study addressed whether a teleost fish, Xenotoca eiseni, was liable to the Bateson effect. Three experiments were designed, by handling the visual stimuli (i.e., a full red disk, an amputated red disk, a red cross) and the presence of an exposure phase, before performing a discriminative learning task (Exp. 1: full red disk vs. amputated red disk; Exp. 2: full red disk vs. red cross). In the exposure phase, three conditions per pairs of training stimuli were arranged: "congruence", where fish were exposed and trained to choose the same stimulus; "wide-incongruence", where fish were exposed to one stimulus and trained to choose the other one; "narrow-incongruence", where fish were exposed to both the stimuli and trained to choose one of them. In the absence of exposure (Exp. 3), the discrimination learning task was carried out to establish a baseline performance as regards the full red disk vs. amputated red disk, and the full red disk vs. red cross. Results showed that fish ran into retardation effects at learning when trained to choose a novel stimulus with respect to the one experienced during the exposure-phase (wide-incongruence condition), as well as after being simultaneously exposed to both stimuli (narrow-incongruence condition). Furthermore, there were no facilitation effects due to the congruence compared with the baseline: in such a case, familiar stimuli did not ease the performance at learning. The study provides the first evidence about the consistency of the classifying-together effect in a fish species, further highlighting the impact of visual similarities on discrimination processes.
Topics: Animals; Conditioning, Operant; Cyprinodontiformes; Discrimination Learning; Learning
PubMed: 36006895
DOI: 10.1371/journal.pone.0272773 -
Frontiers in Veterinary Science 2015This review discusses terminology, pathological, clinical, and magnetic resonance imaging (MRI) findings, treatment, outcome, and prognostic factors of... (Review)
Review
This review discusses terminology, pathological, clinical, and magnetic resonance imaging (MRI) findings, treatment, outcome, and prognostic factors of fibrocartilaginous embolic myelopathy (FCEM), acute non-compressive nucleus pulposus extrusion (ANNPE), and intradural/intramedullary intervertebral disk extrusion (IIVDE). FCEM, ANNPE, and IIVDE have a similar clinical presentation characterized by peracute onset of neurological dysfunction that is generally non-progressive after the initial 24-48 h. Differentiating between these conditions can be challenging, however, certain clinical and imaging findings can help. FCEM can occur in both adult and immature animals, whereas ANNPE or IIVDE have been reported only in animals older than 1 year. In dogs, ANNPE and IIVDE most commonly occur in the intervertebral disk spaces between T12 and L2, whereas FCEM has not such site predilection. In cats, FCEM occurs more frequently in the cervical spinal cord than in other locations. Data on cats with ANNPE and IIVDE are limited. Optimal MRI definition and experience in neuroimaging can help identify the findings that allow differentiation between FCEM, ANNPE, and IIVDE. In animals with ANNPE and IIVDE, the affected intervertebral disk space is often narrowed and the focal area of intramedullary hyperintensity on T2-weighted images is located above the affected intervertebral disk space. In dogs with ANNPE signal changes associated with the extruded nucleus pulposus and epidural fat disruption can be identified in the epidural space dorsal to the affected intervertebral disk. Identification of a linear tract (predominantly hyperintense on T2-weighted images, iso to hypointense on T1-weighted images and hypointense on T2*-weighted gradient recall echo images) extending from the intervertebral disk into the spinal cord parenchyma is highly suggestive of IIVDE. Treatment of FCEM and ANNPE is conservative. Dogs reported with IIVDE have been managed either conservatively or surgically. Prognostic factors include degree of neurological dysfunction (particularly loss of nociception) and disease-specific MRI variables.
PubMed: 26664953
DOI: 10.3389/fvets.2015.00024 -
Journal of Clinical Microbiology Jun 2017This study was conducted to determine the effect of testing parameters on the activity of gepotidacin, a new triazaacenaphthylene antibacterial agent for the treatment... (Comparative Study)
Comparative Study
This study was conducted to determine the effect of testing parameters on the activity of gepotidacin, a new triazaacenaphthylene antibacterial agent for the treatment of conventional and biothreat pathogens. CLSI methods, and variations of those methods, were used to test 10 , 10 , 10 , and 5 isolates by MIC and 30 , 15 , and 15 isolates by disk diffusion (DD) methods. Levofloxacin and linezolid were tested as comparator agents for MIC and DD methods, respectively. Broth microdilution (BMD), macrodilution (MD), and agar dilution (AD) methods were compared. Variations in media, temperature, incubation time, CO level, and inoculum concentration were tested by all methods, and variations in pH, calcium, magnesium, zinc, potassium, thymidine, and polysorbate 80 levels were tested by BMD and DD. The addition of albumin, serum, and lung surfactant was studied by BMD. The variables that impacted the results the most were high inoculum and pH 5.5 (no growth of and by BMD). Gepotidacin AD MIC levels were increased and disk zone diameters were decreased for all species in 10% CO incubation. The following variables had a minimal effect on gepotidacin results: pH, agar method, atmospheric condition, temperature, and addition of serum and albumin for broth methods. There were also some slight differences in gepotidacin disk results between disk manufacturers and some agar types and also with potassium and thymidine for For all other variations, gepotidacin MIC and disk results were considered comparable to reference results.
Topics: Acenaphthenes; Anti-Bacterial Agents; Bacteria; Heterocyclic Compounds, 3-Ring; Microbial Sensitivity Tests
PubMed: 28330893
DOI: 10.1128/JCM.02366-16 -
Journal of Clinical Microbiology Aug 2018Expedited pathways to antimicrobial agent approval by the U.S. Food and Drug Administration (FDA) have led to increased delays between drug approval and the availability... (Review)
Review
The Continued Value of Disk Diffusion for Assessing Antimicrobial Susceptibility in Clinical Laboratories: Report from the Clinical and Laboratory Standards Institute Methods Development and Standardization Working Group.
Expedited pathways to antimicrobial agent approval by the U.S. Food and Drug Administration (FDA) have led to increased delays between drug approval and the availability of FDA-cleared antimicrobial susceptibility testing (AST) devices. Antimicrobial disks for use with disk diffusion testing are among the first AST devices available to clinical laboratories. However, many laboratories are reluctant to implement disk diffusion testing for a variety of reasons, including dwindling proficiency with this method, interruptions of the laboratory workflow, uncertainty surrounding the quality and reliability of disk diffusion tests, and a perceived need to report MIC values to clinicians. This minireview provides a report from the Clinical and Laboratory Standards Institute Methods Development and Standardization Working Group on the current standards and clinical utility of disk diffusion testing.
Topics: Clinical Laboratory Techniques; Disk Diffusion Antimicrobial Tests; Humans; Reference Standards; Reproducibility of Results
PubMed: 29743302
DOI: 10.1128/JCM.00437-18 -
The British Journal of Ophthalmology Jan 1978
Topics: Humans; Optic Disk; Optic Nerve
PubMed: 629906
DOI: 10.1136/bjo.62.1.1 -
Frontiers in Medicine 2022To evaluate the clinical characteristics of myopic choroidal neovascularization (mCNV) according to peripapillary atrophy (PPA) and optic disk tilt and to explore...
PURPOSE
To evaluate the clinical characteristics of myopic choroidal neovascularization (mCNV) according to peripapillary atrophy (PPA) and optic disk tilt and to explore whether those myopic disk deformations are associated with the prognosis of mCNV.
METHODS
Patients with subfoveal mCNV who received intravitreal bevacizumab injection and followed for ≥3 years were included. PPA was quantified as area of the ß-zone PPA/disk area ratio (PDR) and optic disk tilt as the tilt ratio (the longest/shortest disk diameter). We compared the clinical characteristics in terms of PDR and tilt ratio and identified the poor prognostic factors using Logistic regression and Cox proportional hazard model.
RESULTS
Among 80 eyes of 80 patients, 29 (36.30%) eyes developed macular atrophy during 80.71 ± 34.76 months. PDR and tilt ratio are strongly correlated with each other ( = 0.004). Higher PDR showed significant correlations with longer axial length ( = 0.013), worse baseline and final VA ( = 0.007 and = 0.047), and thinner subfoveal choroidal thickness ( = 0.039), while higher tilt ratio showed significant correlations only with longer axial length ( = 0.036). High PDR was also an independent risk factor for both macular atrophy (OR = 2.257, < 0.001) and poor visual outcome (HR = 1.174, = 0.007), while high disk tilt ratio was not.
CONCLUSION
Subfoveal mCNV with higher ß-zone PPA area/disk area ratio had worse functional and structural outcomes.
PubMed: 35979214
DOI: 10.3389/fmed.2022.947632 -
Frontiers in Microbiology 2021Ceftazidime-avibactam is a novel synthetic beta-lactam + beta-lactamase inhibitor combination. We evaluated the performance of the gradient diffusion strip method and...
Ceftazidime-avibactam is a novel synthetic beta-lactam + beta-lactamase inhibitor combination. We evaluated the performance of the gradient diffusion strip method and the disk diffusion method for the determination of ceftazidime-avibactam against and Antimicrobial susceptibility testing of 302 clinical and isolates from two centers were conducted by broth microdilution (BMD), gradient diffusion strip method, and disk diffusion method for ceftazidime-avibactam. Using BMD as a gold standard, essential agreement (EA), categorical agreement (CA), major error (ME), and very major error (VME) were determined according to CLSI guidelines. CA and EA rate > 90%, ME rate < 3%, and VME rate < 1.5% were considered as acceptable criteria. Polymerase chain reaction and Sanger sequencing were performed to determine the carbapenem resistance genes of all 302 isolates. A total of 302 strains were enrolled, among which 182 strains were from center 1 and 120 strains were from center 2. A percentage of 18.21% (55/302) of the enrolled isolates were resistant to ceftazidime-avibactam. The CA rates of the gradient diffusion strip method for and were 100% and 98.65% (73/74), respectively, and the EA rates were 97.37% (222/228) and 98.65% (73/74), respectively. The CA rates of the disk diffusion method for and were 100% and 95.95% (71/74), respectively. No VMEs were found by using the gradient diffusion strip method, while the ME rate was 0.40% (1/247). No MEs were found by using the disk diffusion method, but the VME rate was 5.45% (3/55). Therefore, all the parameters of the gradient diffusion strip method were in line with acceptable criteria. For 31 , 33 , 7 , and 2 positive isolates, both CA and EA rates were 100%; no MEs or VMEs were detected by either method. For 15 carbapenemase-non-producing resistant isolates, the CA and EA rates of the gradient diffusion strips method were 100%. Whereas the CA rate of the disk diffusion method was 80.00% (12/15), the VME rate was 20.00% (3/15). The gradient diffusion strip method can meet the needs of clinical microbiological laboratories for testing the susceptibility of ceftazidime-avibactam drugs. However, the VME rate > 1.5% (5.45%) by the disk diffusion method. By comparison, the performance of the gradient diffusion strip method was better than that of the disk diffusion method.
PubMed: 34603236
DOI: 10.3389/fmicb.2021.710526 -
Materials (Basel, Switzerland) Oct 2022Titanium dioxide (TiO), by its tribological behavior, is known as a solid lubricant. TiO as a solid lubricant, together with tungsten disulfide (WS) and molybdenum...
Titanium dioxide (TiO), by its tribological behavior, is known as a solid lubricant. TiO as a solid lubricant, together with tungsten disulfide (WS) and molybdenum disulfide (MoS) decreases friction and excessive wear. By compacting TiO powder, pellets are formed. Studies and research on the solid lubricant coatings were conducted with success on a tribometer with the possibility of making two simultaneous contacts, pellet/disk, and slider pad/disk. On the disk of a tribometer, we studied the lubrication characteristics of the TiO powder particles as the third body by intentionally transferring. Results show that the TiO pellet behaved like an effective oil-free lubricant by self-repairing and self-replenishing. In experiments, a TiO pellet is intentionally sheared against the surface of the disk, while the slider pad slips loaded on the lubricated surface until the deposited powder film is exhausted. A theoretical model control volume fractional coverage (CVFC) was used to estimate both the wear rate for the lubricated pellet/disk sliding contact and the friction coefficient at the pad/disk separation surface. According to materials properties, disk velocity, pellet and slider pad load, the pellet wear rate, and slider pad friction coefficient, using the CVFC model, can establish the pellet wear rate, and slider pad friction coefficient. The fractional coverage represents a parameter of the CVFC model that varies with time, and it is useful for estimating the film amount from the third body that covers the disk asperities. Model results well enough describe the tribological behavior of the sliding contacts in experiments, both qualitatively and quantitatively. In addition, the theoretical results obtained by modeling and the experimental those obtained in the process of friction, are compared.
PubMed: 36295214
DOI: 10.3390/ma15207145