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101.
Miu Okubo Risako Chiba Takeo Karakida Hajime Yamazaki Ryuji Yamamoto Saeko Kobayashi Takahiko Niwa Henry C. Margolis Takatoshi Nagano Yasuo Yamakoshi Kazuhiro Gomi 《Journal of oral biosciences / JAOB, Japanese Association for Oral Biology》2019,61(1):43-54
Objectives
To investigate potential functions of transforming growth factor-beta (TGF-β) isoforms in maturation-stage ameloblasts during amelogenesis.Methods
In vivo activation of TGF-β was characterized by using matrix metalloproteinase 20 null (Mmp20-/-) and wild-type (Mmp20+/+) mice. Using mHAT9d cells cultured in the presence of each TGF-β isoform, (1) cell proliferation was determined by MTS assay, (2) immunostaining with anti-cleaved caspase-3 monoclonal antibody was performed and apoptotic indices were measured, (3) gene expression was analyzed by RT-qPCR, and (4) the uptake of amelogenin into mHAT9d cells was directly observed using a fluorescence microscope.Results
TGF-β1 and TGF-β3 were present in the enamel matrix of developing teeth which were activated by MMP20 in vivo. A genetic study revealed that the three TGF-β isoforms upregulate kallikrein 4 (KLK4) mRNA levels but downregulate carbonic anhydrase II. Moreover, TGF-β1 and TGF-β2 significantly upregulated the mRNA level of amelotin, whereas TGF-β3 dramatically downregulated the mRNA levels of odontogenic ameloblast-associated protein (ODAM), family with sequence similarity 83 member H (FAM83H), and alkaline phosphatase (ALP). Immunostaining analysis showed that the apoptosis of mHAT9d cells is induced by three TGF-β isoforms, with TGF-β3 being most effective. Both TGF-β1 and TGF-β3 induced endocytosis of amelogenin.Conclusions
We propose that TGF-β is regulated in an isoform-specific manner to perform multiple biological functions such as gene expression related to the structure of basal lamina/ameloblasts, mineral ion transport, apoptosis, and endocytosis in maturation-stage ameloblasts. 相似文献102.
Alan Schwartz Melissa J. Margolis Sara Multerer Hilary M. Haftel Daniel J. Schumacher The APPD LEARN–NBME Pediatrics Milestones Assessment Group 《Medical teacher》2016,38(10):995-1002
Background: The Pediatrics Milestones Assessment Pilot employed a new multisource feedback (MSF) instrument to assess nine Pediatrics Milestones among interns and subinterns in the inpatient context.Objective: To report validity evidence for the MSF tool for informing milestone classification decisions.Methods: We obtained MSF instruments by different raters per learner per rotation. We present evidence for validity based on the unified validity framework.Results: One hundred and ninety two interns and 41 subinterns at 18 Pediatrics residency programs received a total of 1084 MSF forms from faculty (40%), senior residents (34%), nurses (22%), and other staff (4%). Variance in ratings was associated primarily with rater (32%) and learner (22%). The milestone factor structure fit data better than simpler structures. In domains except professionalism, ratings by nurses were significantly lower than those by faculty and ratings by other staff were significantly higher. Ratings were higher when the rater observed the learner for longer periods and had a positive global opinion of the learner. Ratings of interns and subinterns did not differ, except for ratings by senior residents. MSF-based scales correlated with summative milestone scores.Conclusion: We obtain moderately reliable MSF ratings of interns and subinterns in the inpatient context to inform some milestone assignments. 相似文献
103.
D. Scot Malay DPM MSCE FACFAS David J. Margolis MD PhD Ole J. Hoffstad MA Scarlett Bellamy ScD 《The Journal of foot and ankle surgery》2006,45(6):366-374
The primary goal of this retrospective cohort study was to determine the incidence of failure to heal after lower extremity amputation for the treatment of diabetic neuropathic foot ulcer, and the secondary goal was to identify risk factors associated with the outcome. We evaluated 1775 patients who underwent amputation for the treatment of 5314 neuropathic foot ulcers, and who were treated in a network of wound care centers. We calculated the incidence of failure to heal after the initial amputation, and used generalized estimation equations and generalized linear latent and mixed model regression to evaluate the association of failure to heal by the 20th week of care. The unadjusted incidence of failure to heal was 34.01%, and male sex, number of wounds, wound grade, and adjunct therapy were all significantly associated with failure to heal. With the exception of wound grade, the associations were not significantly affected by the treating wound care center, and a sensitivity analysis showed the results to be resistant to the theoretical influence of an unmeasured potential confounder. These findings should be useful to clinicians treating diabetic neuropathic foot ulcers, and should aid surgeons in the determination of the most appropriate level for lower extremity amputation. 相似文献
104.
105.
E.D. Dommasch D.B. Shin A.B. Troxel D.J. Margolis J.M. Gelfand 《The British journal of dermatology》2010,162(4):835-842
Background The development of a simple, reliable, valid and responsive method for measuring the extent of skin involvement in psoriasis is important for use in epidemiological studies. Objectives We sought to investigate the psychometric characteristics of the Patient Report of Extent of Psoriasis Involvement (PREPI), a single‐question method for measuring body surface area affected by psoriasis. Methods This was a cross‐sectional study of 140 patients with psoriasis, with an exploratory prospective longitudinal cohort component. Reliability was measured via a test‐retest approach and criterion validity was investigated by comparing the PREPI with an assessment of body surface area of involvement by a dermatologist. We additionally compared Skindex‐29 scores with the PREPI. To demonstrate responsiveness and establish a minimally important difference in the PREPI, we created receiver operating characteristic curves for the PREPI instrument. Results The test‐retest reliability of the PREPI was nearly perfect [intraclass correlation coefficient (ICC) = 0·99, 95% confidence interval (CI) 0·97–0·99], and there was substantial agreement between patient and physician assessments (ICC = 0·82, 95% CI 0·75–0·87). The PREPI showed significant correlations with all Skindex‐29 domains. We found the PREPI to be responsive to change and identified changes in the PREPI score that have good discrimination between patients with and without a minimally important clinical difference. Conclusions Our study suggests that the PREPI is a reliable, valid and responsive measure of body surface area affected by psoriasis that may be useful for future epidemiological research. 相似文献
106.
Background: Calcium channel blockers potentiate the effects of local anaesthetics. We examined the effect of adding verapamil to local anaesthetic solution on anaesthetic duration in patients undergoing surgery under brachial plexus block. 相似文献
107.
108.
JME Kovoor RD Thomas HS Chandrashekhar PN Jayakumar S Pillai SK Shankar 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):406-411
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature. 相似文献
109.
Gary D Slade R Gary Rozier Leslie P Zeldin Peter A Margolis 《BMC health services research》2007,7(1):176
Background
Physicians report willingness to provide preventive dental care, but optimal methods for their training and support in such procedures are not known. This study aimed to evaluate the effect of three forms of continuing medical education (CME) on provision of preventive dental services to Medicaid-enrolled children by medical personnel in primary care physician offices. 相似文献110.
Developmental changes in multifrequency tympanograms 总被引:4,自引:0,他引:4
L Holte R H Margolis R M Cavanaugh 《Audiology : official organ of the International Society of Audiology》1991,30(1):1-24
The normal maturational course of tympanometric shape, static aural acoustic admittance and ear canal wall characteristics were investigated in healthy infants, who were followed at various time intervals in the first 4 months of life. Susceptance and conductance tympanograms were recorded from both ears of each subject at four probe frequencies or more. In addition, quantitative pneumatic otoscopy was performed utilizing air pressure changes of the same magnitude as those typically used in tympanometry. Results for the group were an increase in admittance magnitude with increasing age at frequencies above 226 Hz. Admittance phase angle increased with age at all frequencies, indicating a growing contribution of compliant elements in the first 4 months of life. The course of development of input admittance at the tympanic membrane differed among individual infants. Otoscopic findings indicated that external ear canal differences cannot completely account for tympanometric differences between young infants and adults. 相似文献