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Background/purpose: Self-assessment in dental education is considered a fundamental skill for proficient oral healthcare providers. While previous studies looked at self-assessment in education, few have done so at Japanese institutions. This study aimed to assess potential associations between gender and self-assessment skills in Japanese dental students. Materials and methods: Dental students from Niigata University (n = 301) completed preclinical prosthodontic exercises and self-assessed their practical exam performance. Three calibrated faculty evaluated students' work using the same rubric. The difference between student self-assessment score and mean faculty grade was defined as the student-faculty (S-F) gap, indicating how accurately students evaluated their work. The gap scores were stratified by quartiles by faculty grade and by gender. Regression analysis was used to investigate potential associations. Results: Students mean S-F gap was 2.9 ± 10.5 % with a significant negative association to faculty grades (coefficient, -0.32; P < 0.001). There was no significant difference between male and female students for faculty grades, self-assessment scores, and S-F gaps. When stratified by quartile, mean S-F gaps of bottom quartile students (5.7 ± 11.9 %) were significantly higher than the rest of the class (1.9 ± 9.8 %; P = 0.01), while the mean S-F gaps of students in the top quartile (-0.8 ± 10.2 %) were significantly lower than the rest of the class (4.2 ± 10.3 %; P < 0.001). Conclusion: Niigata University students generally overestimated their performance. Students with higher faculty grades self-assessed themselves more accurately than students with lower faculty grades. Gender did not influence S-F gaps, despite dentistry in Japan shifting toward a female-dominated field.
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Structural nature of glucan chains in the amorphous part of granular starch was examined by iodine vapor treatment and lintnerization. Four iodine-stained amylose-containing normal starches and their waxy counterparts were examined under a microscope before, during, and after lintnerization. The presence of amylose retarded the lintnerization rate. The degree of retardation correlated with the structural type of the amylopectin component, suggesting that potato amylopectin (type 4 structure) interacts with amylose in the granules, whereas in barley granules (type 1 structure) the interaction is very weak. The inclusion complexes with iodine were not degraded by the acid treatment. Therefore, the iodine-glucan chain complex formation could be used to study the structural nature of the flexible, amorphous parts of the starch granules. Indeed, at the end of lintnerization, when 20%-30% of the granules remained, substantial amounts of blue-stained complexes were washed out from the granules especially from amylose-containing barley and maize starch, but also from both normal and waxy cassava and potato starch. The complexation with iodine did not affect the rate of lintnerization. This suggested that single helical structures were present during lintnerization also in the absence of iodine and this conformation was the reason for the acid resistance.
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Superionic conductors, or solid-state ion-conductors surpassing 0.01 S/cm in conductivity, can enable more energy dense batteries, robust artificial ion pumps, and optimized fuel cells. However, tailoring superionic conductors requires precise knowledge of ion migration mechanisms that are still not well understood due to limitations set by available spectroscopic tools. Most spectroscopic techniques do not probe ion hopping at its inherent picosecond timescale nor the many-body correlations between the migrating ions, lattice vibrational modes, and charge screening clouds-all of which are posited to greatly enhance ionic conduction. Here, we develop an ultrafast technique that measures the time-resolved change in impedance upon light excitation, which triggers selective ion-coupled correlations. We also develop a cost-effective, non-time-resolved laser-driven impedance method that is more accessible for lab-scale adoption. We use both techniques to compare the relative changes in impedance of a solid-state Li+ conductor Li0.5La0.5TiO3 (LLTO) before and after UV to THz frequency excitations to elucidate the corresponding ion-many-body-interaction correlations. From our techniques, we determine that electronic screening and phonon-mode interactions dominate the ion migration pathway of LLTO. Although we only present one case study, our technique can extend to O2-, H+, or other charge carrier transport phenomena where ultrafast correlations control transport. Furthermore, the temporal relaxation of the measured impedance can distinguish ion transport effects caused by many-body correlations, optical heating, correlation, and memory behavior.
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BACKGROUND AND PURPOSE: Low-field 64mT portable brain MRI (pMRI) has recently shown diagnostic promise for MS. This study aimed to evaluate the utility of pMRI in assessing dissemination in space (DIS) in patients presenting with optic neuritis and determine whether deploying pMRI in the MS clinic can shorten the time from symptom onset to MRI. MATERIALS AND METHODS: Newly diagnosed optic neuritis patients referred to a tertiary academic MS center from July 2022 to January 2024 underwent both point-of-care pMRI and subsequent conventional 3T MRI (cMRI). Images were evaluated for periventricular (PV), juxtacortical (JC) and infratentorial (IT) lesions. DIS was determined on brain MRI per 2017 McDonald criteria. Test characteristics were computed using cMRI as the reference. Interrater and intermodality agreement between pMRI and cMRI were evaluated using Cohen's kappa. Time from symptom onset to pMRI and cMRI during the study period was compared to the preceding 1.5 years before pMRI implementation using Kruskal-Wallis with post-hoc Dunn's tests. RESULTS: Twenty patients (median age: 32.5 [IQR, 28-40]; 80% females) were included, of whom 9 (45%) and 5 (25%) had DIS on cMRI and pMRI, respectively. Median time interval between pMRI and cMRI was 7 days (IQR, 3.5-12.5). Interrater agreement was very good for PV (95%, κ=0.89), and good for JC and IT lesions (90%, κ=0.69 for both). Intermodality agreement was good for PV (90%, κ=0.80) and JC (85%, κ=0.63), and moderate for IT lesions (75%, κ=0.42) and DIS (80%, κ=0.58). pMRI had a sensitivity of 56% and specificity of 100% for DIS.The median time from symptom onset to pMRI was significantly shorter (8.5 days [IQR 7-12]) compared to the interval to cMRI before pMRI deployment (21 days [IQR 8-49], n=50) and after pMRI deployment (15 days [IQR 12-29], n=30) (both p<0.01). Time from symptom onset to cMRI in those periods was not significantly different (p=0.29). CONCLUSIONS: In optic neuritis patients, pMRI exhibited moderate concordance, moderate sensitivity and high specificity for DIS compared to cMRI. Its integration into the MS clinic reduced the time from symptom onset to MRI. Further studies are warranted to evaluate the role of pMRI in expediting early MS diagnosis and as an imaging tool in resource-limited settings. ABBREVIATIONS: pMRI = portable MRI; cMRI = conventional MRI; pwMS = patients with MS; PV = periventricular; JC= juxtacortical; IT = infratentorial; DIS = dissemination in space.
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OBJECTIVE: Intravenous contrast injection protocol for certain CT studies at our institution was revised in June 2022 in response to the global shortage of iohexol. This included CT head studies performed for neuro-navigation (contrast dose from 90 mL to 70 mL). The quality of these studies was assessed. METHODS: Consecutive CT scans before (n = 32) and after (n = 32) contrast dose reduction were reviewed. Demographic data was obtained from the chart. Subjective observations made by two radiologists in consensus included overall study quality (Likert scale of 1 to 5) and lesion location, margins and internal characteristics that were compared with MRI findings (reference standard) using Fisher's exact test. Superior sagittal sinus attenuation, used as an objective measurement of enhancement, and lesion size were compared using Student's t-test. The institutional database was searched for any study requiring repetition or deemed non-diagnostic. RESULTS/DISCUSSION: The average age (61.1 ± 12.7 years and 61.6 ± 14.9 years) and body surface area (BSA) (1.9 ± 0.3 m2 and 1.9 ± 0.02 m2) was not significantly different (p > 0.05) between groups. There was no significant difference (p > 0.05) in objective or subjective enhancement between the two groups. There was no significant difference between CT and MRI for lesion size, location, number, margins and internal enhancement characteristics in the two groups. No study required repetition or was reported as non-diagnostic. There was no adverse comment about study quality in operative notes. CONCLUSION: Reduced contrast dose neuro-navigation CT head studies are not different in quality compared to the conventional studies.
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An African American patient in their 60s with a history of monoclonal gammopathy of unknown significance presents to the oculoplastic service for intermittent, bilateral upper eyelid swelling and pain for 2 years. Examination reveals hyperpigmented, spongy eyelid edema with redundant skin, and no lymphadenopathy is present. What would you do next?
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Edema , Enfermedades de los Párpados , Humanos , Negro o Afroamericano , Edema/diagnóstico , Edema/etiología , Enfermedades de los Párpados/diagnóstico , Enfermedades de los Párpados/etnologíaRESUMEN
PURPOSE: This study aims to evaluate how student performance and perspectives changed when the Objective Structured Clinical Exam (OSCE) assessment system was changed from a composite score to discipline-specific grading at the Harvard School of Dental Medicine. METHODS: The retrospective study population consisted of all students (n = 349) who completed three OSCEs (OSCE 1, 2, and 3) as part of the predoctoral program during the years 2014-2023. Data on the students' OSCE scores were obtained from the Office of Dental Education, and data on students' race/ethnicity and gender were obtained from their admissions data. RESULTS: The likelihood of a student failing the OSCE after the assessment system change significantly increased with an adjusted odds ratio of 20.12. After the change, the number of failed subjects per student decreased with an adjusted mean ratio of 0.48. Students perceived the OSCE as being less useful after the change. Independent of the grading change, OSCEs 1 and 2 were seen as more useful compared to OSCE 3, which is administered in the last year of the Doctor of Dental Medicine program. CONCLUSION: The discipline-specific nature of the new assessment system helps focus on specific areas of remediation, rather than blanket remediation used previously, in order to isolate the actual areas of deficiency and to focus remediation efforts so that students can align their learning needs appropriately. Therefore, although the actual number of fails identified increased for the course, the assessment change has allowed for more directed, actionable information to be gained from the OSCE to prepare students to work toward competency standards.
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PURPOSE/OBJECTIVE: A career in healthcare is built on the foundations of continuous self-reflection and self-assessment. Previous studies have solely compared student self-assessment to faculty grades in a single discipline. The objective of this study was to investigate whether associations of a student's self-assessment skills exist across multiple disciplines in the predoctoral setting. METHODS: Sixty-five students from two class years at the Harvard School of Dental Medicine completed preclinical competency exams in dental anatomy waxing and operative dentistry. The difference between the student's self-assessment score and average faculty grade for each exercise was calculated as the studentâfaculty (S-F) gap, which served as a proxy to determine how students evaluate their work. Regression analysis was performed to assess associations between wax-up and preclinical operative S-F gaps. RESULTS: Mean S-F gaps for waxing and preclinical operative procedures were positive (5.7 ± 6.1 and 7.6 ± 6.7, respectively). Additionally, students in the lower quartile tended to overestimate performance to a greater degree than their peers in the upper quartile. Furthermore, the waxing S-F gaps were positively associated with S-F gaps of each operative procedure, particularly with the combined operative exercise S-F gaps, where a statistically significant association was seen (coefficient = 0.28; p = 0.04). CONCLUSION(S): Previously, we identified a negative correlation between students' self-assessment skills (S-F gaps) and their preclinical performance. In this study, we further demonstrated an association of S-F gaps in two fundamental exercises: wax-up and operative dentistry. This underscores the roles of S-F gaps as possible indicators of students' preclinical and clinical performance, and it holds potential to become a widely standardized and applicable calculation that may help evaluate the effectiveness of the dental curricula and optimize student learning.
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Chitosan acts as a versatile carrier in polymeric nanoparticle (NP) for diverse drug administration routes. Delivery of antioxidants, such as quercetin (Qu) showcases potent antioxidant and anti-inflammatory properties for reduction of various cardiovascular diseases, but low water solubility limits uptake. To address this, we developed a novel layer-by-layer zein/gamma-polyglutamic acid (γPGA)/low-molecular-weight chitosan (LC)/fucoidan NP for encapsulating Qu and targeting inflamed vessel endothelial cells. We used zein (Z) and γPGA (r) to encapsulate Qu (Qu-Zr NP) exhibited notably higher encapsulation efficiency compared to zein alone. Qu-Zr NP coated with LC (Qu-ZrLC2 NP) shows a lower particle size (193.2 ± 2.9 nm), and a higher zeta potential value (35.2 ± 0.4 mV) by zeta potential and transmission electron microscopy analysis. After coating Qu-ZrLC2 NP with fucoidan, Qu-ZrLC2Fa NP presented particle size (225.16 ± 0.92 nm), zeta potential (-25.66 ± 0.51 mV) and maintained antioxidant activity. Further analysis revealed that Qu-ZrLC2Fa NP were targeted and taken up by HUVEC cells and EA.hy926 endothelial cells. Notably, we observed Qu-ZrLC2Fa NP targeting zebrafish vessels and isoproterenol-induced inflamed vessels of rat. Our layer-by-layer formulated zein/γPGA/LC/fucoidan NP show promise as a targeted delivery system for water-insoluble drugs. Qu-ZrLC2Fa NP exhibit potential as an anti-inflammatory therapeutic for blood vessels.
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Antioxidantes , Quitosano , Nanopartículas Capa por Capa , Ácido Poliglutámico , Polisacáridos , Quercetina , Pez Cebra , Zeína , Animales , Humanos , Masculino , Ratas , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antioxidantes/farmacología , Antioxidantes/química , Vasos Sanguíneos/efectos de los fármacos , Quitosano/química , Portadores de Fármacos/química , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/patología , Nanopartículas Capa por Capa/química , Peso Molecular , Tamaño de la Partícula , Ácido Poliglutámico/química , Ácido Poliglutámico/análogos & derivados , Ácido Poliglutámico/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Quercetina/farmacología , Quercetina/química , Zeína/químicaRESUMEN
The 22q11.2 locus contains genes critical for brain development. Reciprocal Copy Number Variations (CNVs) at this locus impact risk for neurodevelopmental and psychiatric disorders. Both 22q11.2 deletions (22qDel) and duplications (22qDup) are associated with autism, but 22qDel uniquely elevates schizophrenia risk. Understanding brain phenotypes associated with these highly penetrant CNVs can provide insights into genetic pathways underlying neuropsychiatric disorders. Human neuroimaging and animal models indicate subcortical brain alterations in 22qDel, yet little is known about developmental differences across specific nuclei between reciprocal 22q11.2 CNV carriers and typically developing (TD) controls. We conducted a longitudinal MRI study in a total of 385 scans from 22qDel (n = 96, scans = 191, 53.1% female), 22qDup (n = 37, scans = 64, 45.9% female), and TD controls (n = 80, scans = 130, 51.2% female), across a wide age range (5.5-49.5 years). Volumes of the thalamus, hippocampus, amygdala, and anatomical subregions were estimated using FreeSurfer, and the linear effects of 22q11.2 gene dosage and non-linear effects of age were characterized with generalized additive mixed models (GAMMs). Positive gene dosage effects (volume increasing with copy number) were observed for total intracranial and whole hippocampus volumes, but not whole thalamus or amygdala volumes. Several amygdala subregions exhibited similar positive effects, with bi-directional effects found across thalamic nuclei. Distinct age-related trajectories were observed across the three groups. Notably, both 22qDel and 22qDup carriers exhibited flattened development of hippocampal CA2/3 subfields relative to TD controls. This study provides novel insights into the impact of 22q11.2 CNVs on subcortical brain structures and their developmental trajectories.
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Variaciones en el Número de Copia de ADN , Síndrome de DiGeorge , Dosificación de Gen , Imagen por Resonancia Magnética , Humanos , Femenino , Masculino , Variaciones en el Número de Copia de ADN/genética , Adulto , Adolescente , Niño , Adulto Joven , Persona de Mediana Edad , Preescolar , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/patología , Síndrome de DiGeorge/diagnóstico por imagen , Estudios Longitudinales , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Hipocampo/crecimiento & desarrollo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/crecimiento & desarrollo , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/patología , Tálamo/diagnóstico por imagen , Tálamo/crecimiento & desarrollo , Tálamo/patología , Tamaño de los ÓrganosRESUMEN
Spatial perception and psychomotor skills are critical components to clinical dentistry. However, measures within the dental school curricula have not been sufficiently studied and evaluated for their effectiveness in predicting preclinical performance. The objective of this study was to examine whether students' waxing skills are associated with preclinical operative performance. This study included 65 students from two class years at the Harvard School of Dental Medicine. Regression analysis was utilized to assess associations between waxing scores and operative exam scores. Waxing scores were found to be positively correlated with all operative practical exam scores and significantly associated with the class III resin composite restoration (coefficient, 0.42; P = 0.02) and the combined operative exam scores (coefficient, 0.33; P = 0.04). Wax-up assessments could serve as a predictor for preclinical performance and identify students who would benefit from additional assistance to help foster a more inclusive learning environment.
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Muir-Torre syndrome (MTS) is a rare subtype of hereditary nonpolyposis colorectal cancer syndrome caused by a defect in DNA mismatch repair leading to microsatellite instability. It is characterized by the presence of at least one sebaceous gland tumor and one internal malignancy, most commonly colorectal and endometrial tumors. These patients have a high propensity for tumorigenesis, and while strict screening protocols are in place, there are only two cases that describe the management approach to recurrent colon cancer. Here, we present a case of recurrent colorectal cancer in a patient with MTS, and describe how it was managed at our facility by a multidisciplinary team.
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BACKGROUND AND PURPOSE: To evaluate the reliability and accuracy of nonaneurysmal perimesencephalic subarachnoid hemorrhage (NAPSAH) on Noncontrast Head CT (NCCT) between numerous raters. MATERIALS AND METHODS: 45 NCCT of adult patients with SAH who also had a catheter angiography (CA) were independently evaluated by 48 diverse raters; 45 raters performed a second assessment one month later. For each case, raters were asked: 1) whether they judged the bleeding pattern to be perimesencephalic; 2) whether there was blood anterior to brainstem; 3) complete filling of the anterior interhemispheric fissure (AIF); 4) extension to the lateral part of the sylvian fissure (LSF); 5) frank intraventricular hemorrhage; 6) whether in the hypothetical presence of a negative CT angiogram they would still recommend CA. An automatic NAPSAH diagnosis was also generated by combining responses to questions 2-5. Reliability was estimated using Gwet's AC1 (κG), and the relationship between the NCCT diagnosis of NAPSAH and the recommendation to perform CA using Cramer's V test. Multi-rater accuracy of NCCT in predicting negative CA was explored. RESULTS: Inter-rater reliability for the presence of NAPSAH was moderate (κG = 0.58; 95%CI: 0.47, 0.69), but improved to substantial when automatically generated (κG = 0.70; 95%CI: 0.59, 0.81). The most reliable criteria were the absence of AIF filling (κG = 0.79) and extension to LSF (κG = 0.79). Mean intra-rater reliability was substantial (κG = 0.65). NAPSAH weakly correlated with CA decision (V = 0.50). Mean sensitivity and specificity were 58% (95%CI: 44%, 71%) and 83 % (95%CI: 72 %, 94%), respectively. CONCLUSION: NAPSAH remains a diagnosis of exclusion. The NCCT diagnosis was moderately reliable and its impact on clinical decisions modest.
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Hemorragia Subaracnoidea , Tomografía Computarizada por Rayos X , Humanos , Hemorragia Subaracnoidea/diagnóstico por imagen , Reproducibilidad de los Resultados , Femenino , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Anciano , Adulto , Variaciones Dependientes del Observador , Sensibilidad y Especificidad , Angiografía por Tomografía Computarizada/métodos , Angiografía Cerebral/métodosRESUMEN
BACKGROUND: Performing routine brain magnetic resonance imaging (MRI) is widely accepted as the standard of care for disease monitoring in multiple sclerosis (MS), but the utility of performing routine spinal cord (SC) MRI for this purpose is still debatable. OBJECTIVE: This study aimed to measure the frequency of new isolated cervical spinal cord lesions (CSLs) in people with MS (pwMS) undergoing routine brain and cervical SC-MRI for disease monitoring and determine the factors associated with the development of new CSLs and their prognostic value. METHODS: We retrospectively identified 1576 pwMS who underwent follow-up 3T brain and cervical SC-MRI over a 9-month period. MRI was reviewed for the presence of new brain lesions (BLs) and CSLs. Clinical records were reviewed for interval relapses between sequential scans and subsequent clinical relapse and disability worsening after the follow-up MRI. RESULTS: In 1285 pwMS (median interval: 13-14 months) who were clinically stable with respect to relapses, 73 (5.7%) had new CSLs, of which 49 (3.8%) had concomitant new BLs and 24 (1.9%) had new isolated CSLs only. New asymptomatic CSLs were associated with ⩾ 3 prior relapses (p = 0.04), no disease-modifying therapy (DMT) use (p = 0.048), and ⩾ 3 new BLs (p < 0.001); ⩾ 3 new BLs (OR: 7.11, 95% CI: 4.3-11.7, p < 0.001) remained independently associated with new CSLs on multivariable analysis. Having new asymptomatic CSLs was not independently associated with subsequent relapse or disability worsening after the follow-up MRI (median follow-up time of 26 months). CONCLUSION: Routine brain and cervical SC-MRI detected new isolated CSLs in only < 2% of clinically stable pwMS. Developing new asymptomatic CSLs was associated with concomitant new BLs and did not confer an independent increased risk of relapse or disability worsening. Performing SC-MRI may not be warranted for routine monitoring in most pwMS, and performing only brain MRI may be sufficient to capture the vast majority of clinically silent disease activity.