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1.
Eur J Nucl Med Mol Imaging ; 46(12): 2488-2495, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31385013

RESUMEN

BACKGROUND: The contribution of inflammation to the incidence of cardiovascular disease (CVD) has been increasingly recognized in recent years. We investigated the relationship of aortic vascular uptake of 18F-FDG by PET/CT and aortic wall thickness (AWT) by MRI in psoriasis, a chronic inflammatory disease with increased incidence of CVD. One hundred sixty-five patients with plaque psoriasis participated in an ongoing longitudinal cohort study. Subclinical atherosclerosis was assessed as aortic uptake of 18F-FDG by PET/CT reported as target-to-background ratio (TBR) and AWT by MRI reported as maximal thickness. RESULTS: Patients with psoriasis were middle aged, predominantly male, and had mild CV risk by traditional risk factors. Psoriasis severity as measured by PASI score was a notable determinant of AWT (ρ = 0.20, p = 0.01). Moreover, aortic vascular uptake of 18F-FDG associated with AWT by MRI at baseline in unadjusted analysis (ß = 0.27 p = 0.001) and following adjustment for traditional cardiovascular risk factors, waist-to-hip ratio, and statin use (ß = 0.21 p = 0.01). Finally, following 1 year of psoriasis treatment, a decrease in aortic vascular uptake of 18F-FDG was associated with a reduction in AWT in fully adjusted models (ß = 0.33, p = 0.02). CONCLUSION: In conclusion, we demonstrate that psoriasis severity and aortic vascular uptake of 18F-FDG in the aorta were associated with AWT. Following treatment of psoriasis, a decrease in aortic vascular uptake of 18F-FDG was associated with a reduction in AWT at 1 year. These findings suggest that aortic vascular uptake of 18F-FDG is associated with early evidence of vascular disease assessed by aortic wall thickness. Prospective studies in larger populations including other inflammatory diseases are warranted.


Asunto(s)
Aorta/metabolismo , Fluorodesoxiglucosa F18/metabolismo , Imagen por Resonancia Magnética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Psoriasis/diagnóstico por imagen , Psoriasis/metabolismo , Adulto , Aorta/diagnóstico por imagen , Transporte Biológico , Femenino , Humanos , Masculino , Estudios Prospectivos
2.
Eur Urol Focus ; 10(1): 66-74, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37507248

RESUMEN

BACKGROUND: Up to 40% of patients with prostate cancer may develop biochemical recurrence after surgery, with salvage radiation therapy (SRT) being the only curative option. In 2016, Tendulkar et al. (Contemporary update of a multi-institutional predictive nomogram for salvage radiotherapy after radical prostatectomy. J Clin Oncol 2016;34:3648-54) published a nomogram to predict distant metastasis in a cohort of patients treated with SRT with pre-SRT prostate-specific antigen (PSA) of 0.5 ng/ml after radical prostatectomy. In modern practice, SRT is delivered at lower PSA values. OBJECTIVE: To train and externally validate a machine learning model to predict the risk of distant metastasis at 5 yr in a contemporary cohort of patients receiving SRT. DESIGN, SETTING, AND PARTICIPANTS: We trained a machine learning model on data from 2418 patients treated with SRT at one institution, with a median PSA value of 0.27 ng/ml. External validation was done in 475 patients treated at two different institutions. Patients with cM1, pN1, or pT4 disease were excluded, as were patients with PSA >2 ng/ml or PSA 0, and patients with radiation dose <60 or ≥80 Gy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Model performance was assessed using calibration and time-dependent area under the receiver operating curve (tAUC). RESULTS AND LIMITATIONS: Our model had better calibration and showed improved discrimination (tAUC = 0.72) compared with the Tendulkar model (tAUC = 0.60, p < 0.001). The main limitations of this study are its retrospective design and lack of validation on patients who received hormone therapy. CONCLUSIONS: The updated model can be used to provide more individualized risk assessments to patients treated with SRT at low PSA values, improving decision-making. PATIENT SUMMARY: Up to 40% of patients with prostate cancer may develop biochemical recurrence after surgery, with salvage radiation therapy as the only potentially curative option. We trained and validated a machine learning model using clinical and surgical data to predict a patient's risk of distant metastasis at 5 yr after treatment. Our model outperformed the reference tool and can improve clinical decision-making by providing more personalized risk assessment.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Masculino , Humanos , Estudios Retrospectivos , Próstata/patología , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Prostatectomía/métodos , Terapia Recuperativa/métodos
3.
J Dent Educ ; 86(4): 393-400, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34761392

RESUMEN

PURPOSE: Self-assessment is increasingly implemented in medical professions' curricula. In this research, the authors measure the effects of self-assessment within a preclinical removable prosthodontics course among dental students in a private dental school according to the European qualifications framework descriptors. MATERIALS AND METHODS: Thirty subjects, all fourth-year dental students, were included in this experiment. Fifteen subjects were included in each of the experimental and control groups during one semester. The experimental group subjects used the study roadmap tool in their preclinical tasks. The control group subjects executed the same preclinical tasks under instructor supervision only. All subjects were filmed, and an autonomy score was given to every subject per session. At the end of the semester, cognitive skills development was compared using the Kember et al. questionnaire while practical skills development was compared using a comparison of grades. Two focus groups were undertaken with experimental group subjects. Qualitative and quantitative data were collected and statistically analyzed (p < 0.005). RESULTS: Subjects from the experimental group showed development in critical thinking, practical skills, autonomy, and taking responsibility, thus development in the competence level. CONCLUSION: Implementation of self-assessment within preclinical courses may develop skills and competence among dental students, yet more studies are needed.


Asunto(s)
Prostodoncia , Autoevaluación (Psicología) , Competencia Clínica , Curriculum , Evaluación Educacional , Humanos , Prostodoncia/educación , Encuestas y Cuestionarios , Pensamiento
4.
Micromachines (Basel) ; 12(8)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34442511

RESUMEN

This paper presents modeling and analysis of light diffraction and light-intensity modulation performed by an optical phased array (OPA) system based on metal-coated silicon micromirrors. The models can be used in the design process of a microelectromechanical system (MEMS)-based OPA device to predict its optical performance in terms of its field of view, response, angular resolution, and long-range transmission. Numerical results are derived using an extended model for the 1st-order diffracted light intensity modulation due to phase shift. The estimations of the optical characteristics are utilized in the designs of an OPA system capable of active phase modulation and an OPA system capable of array pitch tuning. Both designs are realized using the Multi-User MEMS Processes (PolyMUMPs) in which polysilicon is used as structural material for the MEMS-actuated mirrors. The experiments are performed to evaluate the optical performance of the prototypes. The tests show that the individually actuated micromirrors, which act as phase shifters, can transmit the most optical power along the 1st-order diffracted beam by actively changing their out-of-plane positions. In addition, the 1st-order diffracted beam with high optical intensity can be steered for distance measurement.

5.
J Family Med Prim Care ; 10(6): 2284-2292, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34322426

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is one of the pivotal public health issues in Saudi Arabia currently. There is a need to examine the knowledge and awareness of the health professions' students who are going to be the caretakers of the public in years to come. OBJECTIVES: The aim of this study was to investigate the knowledge and awareness of CRC in health and allied students of our Health Sciences University in Saudi Arabia. MATERIALS AND METHODS: An online predesigned and validated and self-administered Survey/Questionnaire was dispensed to all health and allied students. Descriptive statistics was performed using SPSS. Data were analyzed by demographic distributions to determine if students of these groups displayed any differential awareness and knowledge for CRC. RESULTS: A total of 372 of students answered the online questionnaire with a mean age of 20 + 7.3 (SD) years. There was almost an equal distribution of male (47.8%) and female (52.2%) students and majority of them were single (97.3%). In this study, we found that the students were not having any knowledge of the epidemiology of CRC in Saudi Arabia. The knowledge about the various risk factors of CRC was also very dismal; only a minority of them (34.4%) was able to identify 5 out of 12 CRC risk factors correctly. However, 59.7% of students had no idea about the test/examination methods that are used in screening and detection of CRC, but majority (76.1%) of them were aware that people should get screened for CRC. CONCLUSIONS: A very low level of awareness and knowledge about CRC was observed in this study among all health and allied students. We strongly recommend that there is a dire need of proactive aggressive preventive medicine campaigns, educational programs, and curricular modifications for the students to prepare them for the challenges posed by increasing burden of cancer in the kingdom.

6.
JAMA Dermatol ; 156(2): 151-157, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31746956

RESUMEN

Importance: Psoriasis, a chronic inflammatory skin disease associated with accelerated noncalcified coronary burden (NCB) by coronary computed tomography angiography (CCTA), accelerates lipoprotein oxidation in the form of oxidized modified lipoproteins. A transmembrane scavenger receptor for these oxidized modified lipoproteins is lectinlike oxidized low-density lipoprotein receptor-1 (LOX-1), which has been reported to be associated with coronary artery disease. It is unknown whether this receptor is associated with coronary artery disease in psoriasis. Objective: To assess the association between soluble LOX-1 (sLOX-1) and NCB in psoriasis over time. Design, Setting, and Participants: In a cohort study at the National Institutes of Health, 175 consecutive patients with psoriasis were referred from outpatient dermatology practices between January 1, 2013, and October 1, 2017. A total of 138 consecutively recruited patients with psoriasis were followed up at 1 year. Exposures: Circulating soluble lectinlike oxidized low-density lipoprotein receptor-1 levels were measured blindly by field scientists running undiluted serum using an enzyme-linked immunosorbent assay. Main Outcomes and Measures: Coronary computed tomography angiography scans were performed to quantify NCB in all 3 major epicardial coronary arteries by a reader blinded to patient demographics, visit, and treatment status. Results: Among the 175 patients with psoriasis, the mean (SD) age was 49.7 (12.6) years and 91 were men (55%). The cohort had relatively low median cardiovascular risk by Framingham risk score (median, 2.0 [interquartile range (IQR), 1.0-6.0]) and had a mean (SD) body mass index (calculated as weight in kilograms divided by height in meters squared) suggestive of overweight profiles (29.6 [6.0]). Elevated sLOX-1 levels were found in patients with psoriasis compared with age- and sex-matched controls (median, 210.3 [IQR, 110.9-336.2] vs 83.7 [IQR, 40.1-151.0]; P < .001), and were associated with Psoriasis Area Severity Index (PASI) score (ß = 0.23; 95% CI, 0.082-0.374; P = .003). Moreover, sLOX-1 was associated with NCB independent of hyperlipidemia status (ß = 0.11; 95% CI, 0.016-0.200; P = .023), an association which persisted after adjusting for traditional cardiovascular risk factors, statin use, and biologic psoriasis treatment (ß = 0.10; 95% CI, 0.014-0.193; P = .03). At 1 year, in those who had clinical improvement in PASI (eg, >50% improvement), a reduction in sLOX-1 (median, 311.1 [IQR, 160.0-648.8] vs median, 224.2 [IQR, 149.1 - 427.4]; P = .01) was associated with a reduction in NCB (ß = 0.14; 95% CI, 0.028-0.246; P = .02). Conclusions and Relevance: Soluble lectinlike oxidized low-density lipoprotein receptor-1 levels were elevated in patients with psoriasis and were associated with severity of skin disease. Moreover, sLOX-1 associated with NCB independent of hyperlipidemia status, suggesting that inflammatory sLOX-1 induction may modulate lipid-rich NCB in psoriasis. Improvement of skin disease was associated with a reduction of sLOX-1 at 1 year, demonstrating the potential role of sLOX-1 in inflammatory atherogenesis in psoriasis.


Asunto(s)
Angiografía por Tomografía Computarizada , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Psoriasis/complicaciones , Receptores Depuradores de Clase E/sangre , Adulto , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/sangre , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Psoriasis/patología , Índice de Severidad de la Enfermedad , Factores de Tiempo
7.
Animal Model Exp Med ; 1(3): 221-227, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30891568

RESUMEN

BACKGROUND: The present study covered an assessment of methanolic acetate fractions of Pistia stratiotes, commonly known as water lettuce, for analgesic, anti-inflammatory, and CNS depressant activities. METHODS: The methanol acetate fractions were extracted from Pistia stratiotes and administered to the experimental animals as 200 and 400 mg/kg doses to determine the effect on acetic acid-induced writhing and formalin-induced licking and biting, for the assessment of analgesic activity. The anti-inflammatory assay was done using the carrageenan-induced hind paw edema method, while assessment of CNS depressant activity was done using the open field and hole cross tests. The effects were compared to standard reference drugs. RESULTS: At both doses (200 and 400 mg/kg body weight), the methanolic acetate extract of P. stratiotes showed significant analgesic action (P < 0.05) against acetic acid-induced writhing. The extract was also found to give significant protection against licking and biting at both doses. The methanolic acetate extract of P. stratiotes showed a significant (P < 0.05) anti-inflammatory effect from 0 minutes up to 3 hours in the carrageenan-induced paw edema test. In the CNS depressant assay, the methanolic acetate extract showed significant (P < 0.05) depressant activity at both doses from 30 to 120 minutes in both the hole cross and open field tests. CONCLUSION: Thus we can conclude that P. stratiotes extracts have significant analgesic, anti-inflammatory, and CNS depressant activity, compared to standard compounds, in an animal model.

8.
JAMA Cardiol ; 2(9): 1013-1018, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28564678

RESUMEN

Importance: Inflammation is critical in the development of atherosclerosis. Psoriasis is a chronic inflammatory skin disease that is associated with increased vascular inflammation by 18fluorodeoxyglucose positron emission tomography/computed tomography in vivo and future cardiovascular events. It provides a human model to understand the effect of treating inflammation in a target organ (eg, the skin) on vascular diseases. Objective: To investigate the association between change in skin disease severity and change in vascular inflammation at 1 year and to characterize the impact of 1 year of anti-tumor necrosis factor therapy on vascular inflammation. Design, Setting, and Participants: In this prospective cohort study, 220 participants from outpatient practices were recruited at the US National Institutes of Health. A total of 115 consecutively recruited patients with psoriasis were followed up at 1 year. The study was conducted from January 1, 2013, through October 31, 2016, with data analyzed in November 2016. Exposure: Skin inflammation measured as Psoriasis Area and Severity Index (PASI) score. Main Outcomes and Measures: Vascular inflammation assessed as target-to-background ratio by 18fluorodeoxyglucose positron emission tomography/computed tomography. Results: Among the 115 patients, the mean (SD) age at 1-year follow-up was 50.8 (12.8) years and 68 were men (59%). The cohort had a low cardiovascular risk by Framingham risk score and mild-to-moderate psoriasis, with a median PASI score of 5.2 (interquartile range, 3.0-8.9). At follow-up, the total cohort had a median improvement in PASI score of 33%, with use of topical therapy (60%), biological therapy (66%, mostly anti-tumor necrosis factor) and phototherapy (15%) (P < .001). Moreover, improvement in PASI score was associated with improvement in target-to-background ratio of 6%, mainly driven by those with higher responses in PASI score (P < .001). This association persisted beyond traditional risk factors (ß = 0.19; 95% CI, 0.012-0.375; P = .03) and was the strongest in those initiated with anti-tumor necrosis factor therapy (ß = 0.79; 95% CI, 0.269-1.311; P = .03). Conclusions and Relevance: Improvement in psoriasis skin disease severity was associated with improvement in aortic vascular inflammation by 18fluorodeoxyglucose positron emission tomography/computed tomography, with greater improvement in aortic vascular inflammation observed in those who had higher than 75% reduction in skin disease severity. These findings suggest that controlling remote target organ inflammation (eg, in the skin) may improve vascular diseases; however, randomized clinical trials are needed to confirm these findings.


Asunto(s)
Antirreumáticos/uso terapéutico , Aorta/diagnóstico por imagen , Inflamación/epidemiología , Psoriasis/epidemiología , Adulto , Proteína C-Reactiva/inmunología , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Estudios de Cohortes , Femenino , Fluorodesoxiglucosa F18 , Humanos , Inflamación/diagnóstico por imagen , Inflamación/inmunología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Fototerapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Estudios Prospectivos , Psoriasis/inmunología , Psoriasis/terapia , Radiofármacos , Índice de Severidad de la Enfermedad , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
9.
Saudi Dent J ; 27(3): 149-54, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26236129

RESUMEN

OBJECTIVE: The aim of this study was to compare the fit accuracies of metal partial removable dental prosthesis (PRDP) frameworks fabricated by the traditional technique (TT) or the light-curing modeling material technique (LCMT). MATERIALS AND METHODS: A metal model of a Kennedy class III modification 1 mandibular dental arch with two edentulous spaces of different spans, short and long, was used for the study. Thirty identical working casts were used to produce 15 PRDP frameworks each by TT and by LCMT. Every framework was transferred to a metal master cast to measure the gap between the metal base of the framework and the crest of the alveolar ridge of the cast. Gaps were measured at three points on each side by a USB digital intraoral camera at ×16.5 magnification. Images were transferred to a graphics editing program. A single examiner performed all measurements. The two-tailed t-test was performed at the 5% significance level. RESULTS: The mean gap value was significantly smaller in the LCMT group compared to the TT group. The mean value of the short edentulous span was significantly smaller than that of the long edentulous span in the LCMT group, whereas the opposite result was obtained in the TT group. CONCLUSION: Within the limitations of this study, it can be concluded that the fit of the LCMT-fabricated frameworks was better than the fit of the TT-fabricated frameworks. The framework fit can differ according to the span of the edentate ridge and the fabrication technique for the metal framework.

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