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1.
Epilepsy Behav ; 160: 110074, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39393147

RESUMEN

We aimed to identify factors predicting additional surgical interventions in patients with drug-resistant epilepsy who continue experiencing seizures after mesial temporal laser interstitial thermal therapy (LITT). In a retrospective observational study, we analyzed consecutive patients with drug-resistant temporal epilepsy treated with mesial temporal LITT at the University of Washington between 2013-2022. The primary outcome was subsequent epilepsy surgery to improve seizure control after LITT. Logistic regression was used to assess how clinical factors and travel distance within tertiary center referral regions predict subsequent surgery occurrence. We identified 145 patients treated with mesial temporal LITT. Among the patients, 25 underwent subsequent surgeries, including 17 temporal lobectomies, 5 repeat LITT, 2 responsive neurostimulation, and 1 with deep brain stimulation. Further surgery was associated with higher Engel scores and shorter travel distance to our tertiary epilepsy center. Factors like age, sex, epilepsy duration, surgery on dominant hemisphere, and frequency of convulsive seizures were not significant. Patients who continue to have seizures after LITT are potential candidates for more surgery. Patients who must travel farther are less likely to receive follow-up surgery. Healthcare inequity presents a significant barrier in accessing epilepsy surgery, limiting the potential to achieve improved outcomes for individuals with epilepsy.

2.
Vox Sang ; 118(9): 763-774, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37608544

RESUMEN

BACKGROUND AND OBJECTIVES: Human neutrophil antigens (HNAs) are categorized into five systems: HNA-1 to HNA-5. Given the importance of neutrophils in immunity, we sought to create awareness of the role of HNA diagnostic services in managing immune neutropenia and transfusion-related acute lung injury. To provide health communities all around the world with access to these services, we conducted a survey to create a directory of these HNA diagnostic services. MATERIALS AND METHODS: An Excel table-based survey was created to capture information on the laboratory's location and was emailed to 55 individuals with known or possible HNA investigation activity. The collected data were then summarized and analysed. RESULTS: Of contacted laboratories, the surveys were returned from 23 (38.2%) laboratories; 17 have already established HNA diagnostic (of them 12 were regular participants of the International Granulocyte Immunobiology Workshop [ISBT-IGIW]), 4 laboratories were in the process of establishing their HNA investigation and the remaining 2 responder laboratories, did not conduct HNA investigations. In established laboratories, investigation for autoimmune neutropenia (infancies and adults) was the most frequently requested, and antibodies against HNA-1a and HNA-1b were the most commonly detected. CONCLUSION: The directory of survey respondents provides a resource for health professionals wanting to access HNA diagnostic services. The present study offers a comprehensive picture of HNA diagnostics (typing and serology), identifying weak points and areas for improvement for the first time. Identifying more laboratories involved in HNA diagnostics with limited access to international societies in the field will globally improve HNA diagnostics.


Asunto(s)
Neutropenia , Neutrófilos , Adulto , Humanos , Granulocitos , Anticuerpos , Encuestas y Cuestionarios
3.
Pediatr Allergy Immunol ; 34(7): e13990, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37492921

RESUMEN

BACKGROUND: In order to support the comprehensive classification of Leukocyte Adhesion Deficiency-I (LAD-I) severity by simultaneous screening of CD11a/CD18, this study assessed clinical, laboratory, and genetic findings along with outcomes of 69 LAD-I patients during the last 15 years. METHODS: Sixty-nine patients (40 females and 29 males) with a clinical phenotype suspected of LAD-I were referred to Immunology, Asthma, and Allergy research institute, Tehran, Iran between 2007 and 2022 for further advanced immunological screening and genetic evaluations as well as treatment, were enrolled in this study. RESULTS: The diagnosis median age of the patients was 6 months. Delayed umbilical cord separation was found in 25 patients (36.2%). The median diagnostic delay time was 4 months (min-max: 0-82 months). Forty-six patients (66.7%) were categorized as severe (CD18 and/or CD11a: below 2%); while 23 children (33.3%) were in moderate category (CD18 and/or CD11a: 2%-30%). During the follow-ups, 55.1% of children were alive with a mortality rate of 44.9%. Skin ulcers (75.4%), omphalitis (65.2%), and gingivitis (37.7%) were the most frequent complaints. Genetic analysis of the patients revealed 14 previously reported and three novel pathogenic mutations in the ITGB2 gene. The overall survival of patients with and without hematopoietic stem cell transplantation was 79.3% and 55.6%, respectively. CONCLUSION: Physicians' awareness of LAD-I considering delayed separation of umbilical cord marked neutrophilic leukocytosis, and variability in CD11 and CD18 expression levels, and genetic analysis leads to early diagnosis and defining disease severity. Moreover, the prenatal diagnosis would benefit families with a history of LAD-I.


Asunto(s)
Antígenos CD18 , Síndrome de Deficiencia de Adhesión del Leucocito , Masculino , Embarazo , Femenino , Humanos , Antígenos CD18/genética , Síndrome de Deficiencia de Adhesión del Leucocito/diagnóstico , Síndrome de Deficiencia de Adhesión del Leucocito/genética , Diagnóstico Tardío , Irán , Leucocitos/metabolismo
4.
Adv Exp Med Biol ; 1367: 119-135, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35286694

RESUMEN

Lichen planus (LP) is a multifaceted autoimmune disease affecting the skin, nails, hair, and mucous membranes, with several clinical subgroups. Cell-mediated immunity plays a key role in its progression. This chapter reviews the known genetic associations of lichen planus including HLA as well as non-HLA genes.


Asunto(s)
Enfermedades Autoinmunes , Liquen Plano , Cabello , Humanos , Inmunogenética , Liquen Plano/genética , Piel
5.
BMC Infect Dis ; 21(1): 1278, 2021 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-34952570

RESUMEN

BACKGROUND: Preliminary studies revealed the safety and effectiveness of convalescent plasma (CP) therapy for patients with coronavirus. In this study, we aimed to evaluate and summarize the available evidence on CP therapy, identify the research gap regarding the immunological response to CP therapy and pave the road for future studies. METHODS: This study was conducted according to the Hilary Arksey and Lisa O'Malley framework. To find out the relevant studies, we searched PubMed, Scopus and Embase databases up to 30th May 2021. Data have been extracted according to three categories: (1) patients' characteristics, (2) clinical and immunological responses to CP therapy and (3) pre-infusion screening of the CP samples. RESULTS: A total of 12,553 articles were identified. One hundred fifty-four studies met the inclusion criteria for full-text review. More than half of the included studies (112 studies, (75.6%)) concluded satisfactory outcomes and or safety of CP infusion in patients. Results of studies showed the efficacy of CP therapy in clinical improvement (101 studies), decreasing in the level of inflammatory factors (62 studies), elimination or decreasing in viral load (60 studies), and induction or increase in antibody response (37 studies). Despite these promising results, the results of the 49 studies revealed that CP therapy was ineffective in the survival of patients, clinical improvement, viral infection elimination or decrease in the inflammatory factor levels. Furthermore, the adaptive immune response was evaluated in 3 studies. Information related to the pre-infusion screening for human leukocyte antigen/human neutrophil antigen (HLA/HNA) antibodies was not reported in most of the studies. Our gap analysis revealed that the influence of the CP infusion on the adaptive immune and inflammatory responses in patients with coronavirus needs further investigation. CONCLUSIONS: Based on the results of most included studies, CP infusion was safe and resulted in clinical improvement of patients and decreasing the viral load. The effect of the CP infusion on adaptive immune response and inflammatory cytokines in patients with coronavirus needs further investigation.


Asunto(s)
COVID-19 , Transfusión Sanguínea , Humanos , Inmunización Pasiva , Plasma , SARS-CoV-2
6.
Epilepsy Behav ; 116: 107775, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33571837

RESUMEN

Sudden Unexpected Death in Epilepsy (SUDEP) is strongly linked to prone position in the immediate aftermath of a generalized tonic-clonic seizure (GTCS). The risk of SUDEP after a GTCS resulting in prone position has not yet been estimated. We calculated the probability of SUDEP given prone position after a GTCS using Bayesian analysis with inputs obtained from known risk of SUDEP and probability of prone position after a GTCS. The risk for SUDEP given the prone position is estimated to be 0.41% (95% Credible Interval 0.13-0.69%). The relative risk of SUDEP in prone vs. non-prone position following a GTCS is estimated to be 63 (95% Credible Interval 30-96). Sudden Unexpected Death in Epilepsy might be prevented by repositioning the patient after a seizure to avoid the prone position.


Asunto(s)
Muerte Súbita e Inesperada en la Epilepsia , Teorema de Bayes , Muerte Súbita/epidemiología , Muerte Súbita/etiología , Humanos , Probabilidad , Posición Prona
7.
Neurocrit Care ; 32(1): 162-171, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31093884

RESUMEN

BACKGROUND: The objective of this study was to examine whether heart rate variability (HRV) measures can be used to detect neurocardiogenic injury (NCI). METHODS: Three hundred and twenty-six consecutive admissions with aneurysmal subarachnoid hemorrhage (SAH) met criteria for the study. Of 326 subjects, 56 (17.2%) developed NCI which we defined by wall motion abnormality with ventricular dysfunction on transthoracic echocardiogram or cardiac troponin-I > 0.3 ng/mL without electrocardiogram evidence of coronary artery insufficiency. HRV measures (in time and frequency domains, as well as nonlinear technique of detrended fluctuation analysis) were calculated over the first 48 h. We applied longitudinal multilevel linear regression to characterize the relationship of HRV measures with NCI and examine between-group differences at baseline and over time. RESULTS: There was decreased vagal activity in NCI subjects with a between-group difference in low/high frequency ratio (ß 3.42, SE 0.92, p = 0.0002), with sympathovagal balance in favor of sympathetic nervous activity. All time-domain measures were decreased in SAH subjects with NCI. An ensemble machine learning approach translated these measures into a classification tool that demonstrated good discrimination using the area under the receiver operating characteristic curve (AUROC 0.82), the area under precision recall curve (AUPRC 0.75), and a correct classification rate of 0.81. CONCLUSIONS: HRV measures are significantly associated with our label of NCI and a machine learning approach using features derived from HRV measures can classify SAH patients that develop NCI.


Asunto(s)
Frecuencia Cardíaca/fisiología , Volumen Sistólico , Hemorragia Subaracnoidea/fisiopatología , Disfunción Ventricular Izquierda/fisiopatología , Adulto , Anciano , Isquemia Encefálica/etiología , Ecocardiografía , Electrocardiografía , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Hemorragia Subaracnoidea/complicaciones , Troponina I/sangre , Disfunción Ventricular Izquierda/sangre , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología
8.
Scand J Immunol ; 89(1): e12730, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30375024

RESUMEN

All stages of the inflammatory process involved in T cell-mediated chronic skin disorders like psoriasis are affected by redox imbalance. On the other hand, Th17 cells have a critical role in the pathogenesis of psoriasis. In this study, we evaluated redox status in memory CD4 + T cells and plasma of patients with psoriasis and its correlation with IL-17 response. To this end, memory T cells were isolated from 10 patients with psoriasis and 10 controls. Intracellular Glutathione (GSH), reactive oxygen species (ROS) and superoxide as well as IL-17 were measured using flow cytometry. Plasma total anti-oxidant capacity (TAC) was quantified by ferric reducing ability of plasma (FRAP) assay. The expression of catalase (CAT), superoxide dismutase 1(SOD1), superoxide dismutase 2 (SOD2), nuclear factor, erythroid 2 like 2 (NFE2L2) and cytochrome b-245 beta chain (CYBB) genes were analysed using real-time PCR. Our results showed an increased intracellular ROS production in memory CD4 + T cells of patients compared to controls, (P = 0.04). Furthermore, a significant decrease in expression of catalase gene was found in patients, (P = 0.02). However, no significant differences were observed for intracellular GSH, IL-17 and TAC levels between patients and controls. Also, no correlation was seen between the intracellular IL-17 level and intracellular ROS, GSH and catalase gene expression levels. Collectively, we found an increased ROS production in stimulated memory T cells of patients that could be due to reduced expression of catalase gene. However, it seems that these redox abnormalities have no relationship with IL-17 response in memory T cells.


Asunto(s)
Memoria Inmunológica/inmunología , Interleucina-17/inmunología , Psoriasis/inmunología , Células Th17/inmunología , Adolescente , Adulto , Linfocitos T CD4-Positivos/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Adulto Joven
10.
Cell Biol Int ; 43(12): 1332-1345, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31166051

RESUMEN

Apelin, a member of the adipokine family, is widely distributed in the body and exerts cytoprotective effects on many organs. Apelin isoforms are involved in different physiological processes, including regulation of the cardiovascular system, cardiac contractility, angiogenesis, and energy metabolism. Several investigations have been performed to study the effect of apelin on stem cell therapy. This review aims to summarize the literature representing the effects of apelin on stem cell properties. Furthermore, this review discusses the therapeutic potential of apelin-treated stem cells for cardiovascular diseases and demonstrates the effect of stem cells overexpressing apelin on energy metabolism. Stem cells with their unique characteristics play a crucial role in the maintenance of tissue integrity. These cells participate in tissue regeneration via multiple mechanisms. Although preclinical and clinical studies have demonstrated the therapeutic potential of stem cells in various diseases, their application in regenerative medicine has not been efficient. A number of strategies such as genetic modification or treatment of stem cells with different factors have been used to improve the efficacy of cell therapy and to increase their survival after transplantation. This article reviews the effect of apelin treatment on the efficacy of cell therapy.

11.
Gen Dent ; 66(2): 64-68, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29513239

RESUMEN

One common cause for the replacement of a composite restoration is discoloration. This in vitro study evaluated the effect of tea solution on the discoloration of 3 types of composites at different timepoints after curing. For this study, 150 disc-shaped specimens of 3 types of composite resin-a nanohybrid (Filtek Z350), a microhybrid (Filtek Z250), and a microfilled material (Heliomolar)-were prepared. Specimens were randomly divided into 5 subgroups (n = 10) according to the type of composite and the time from curing to immersion in a tea solution (none [immersed immediately], 1 hour, 6 hours, 12 hours, or 24 hours postcuring). The color for all specimens was measured before and after immersion in tea. Color change (ΔE*) for all specimens was measured, and a ΔE* value of less than 3.3 was considered clinically acceptable. Analysis of variance and a post hoc Tukey test were used to analyze the data (α = 0.05). Immediately after curing, the levels of composite discoloration were deemed clinically acceptable (ΔE* < 3.3). In all composites, the greatest color change was found immediately after curing (P < 0.05). With each subsequent timepoint, the color stability increased. When the groups were immersed in tea 6 hours postcuring, the mean ΔE* value of the Filtek Z350 composite resin specimens was significantly greater than that of Heliomolar specimens (P < 0.05). The mean ΔE* value for specimens immersed 12 hours postcuring was also greater in the Filtek Z250 composite group than in the Heliomolar group (P < 0.05). The ΔE* values of Filtek Z350 and Filtek Z250 composites were not significantly different from each other (P > 0.05), except with 12-hour postcure immersion. The results suggest that patients should avoid the intake of staining foods or beverages for at least 12 hours after placement of a composite resin restoration, although this restriction may be reduced to 1 hour for microfilled composite resins.


Asunto(s)
Resinas Compuestas/química , Materiales Dentales/química , , Decoloración de Dientes/inducido químicamente , Resinas Acrílicas , Técnicas In Vitro , Curación por Luz de Adhesivos Dentales , Ensayo de Materiales , Poliuretanos , Propiedades de Superficie , Factores de Tiempo
12.
Gen Dent ; 66(1): 40-44, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29303753

RESUMEN

Bleaching is a conservative treatment for discolored teeth, but the effect of this treatment on newer, silorane-based composite resins is unclear. This study evaluated the effect of at-home bleaching on the microhardness of methacrylate- and silorane-based composites. Forty blocks each of a methacrylate-based composite and a silorane-based composite were prepared. The 80 specimens were tested in 8 groups (n = 10): 2 composites, each exposed to 3 different carbamide peroxide concentrations (10%, 16%, or 22%) as well as distilled water (control). The surface of the test specimens was covered daily with the bleaching gel at room temperature for the time period recommended by the manufacturer for each carbamide peroxide concentration. A Vickers hardness testing machine was used with a 100-g load for 20 seconds to register specimen microhardness prior to and after 2 weeks of bleaching. The load was applied at 3 points, and the mean microhardness was calculated. Repeated-measures analysis of variance, paired t test, and Tukey test were used to analyze the data. All bleaching concentrations significantly decreased the microhardness of the methacrylate-based composite resin groups, while microhardness was significantly increased in the silorane-based composite resin groups. There was no evident difference in effects among the different gel concentrations (P > 0.05).


Asunto(s)
Peróxido de Carbamida/farmacología , Resinas Compuestas , Blanqueadores Dentales/farmacología , Peróxido de Carbamida/efectos adversos , Resinas Compuestas/química , Relación Dosis-Respuesta a Droga , Dureza/efectos de los fármacos , Pruebas de Dureza , Humanos , Metacrilatos , Resinas de Silorano , Blanqueadores Dentales/efectos adversos
13.
Am J Med Sci ; 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39389358

RESUMEN

According to reports, coronavirus disease 2019 (COVID-19) is associated with various complications, including hematological abnormalities. Lymphopenia and thrombocytopenia have been recognized as common hematological abnormalities. Moreover, some reports have shown cases of neutropenia occurring during or after infection with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Neutropenia is a condition characterized by a decrease in the absolute neutrophil count (ANC) to less than 1500/µ. Although neutropenia has been considered a rare complication of SARS-Cov-2 infection, it is important to closely monitor patients and thoroughly investigate all laboratory findings, particularly in those with severe COVID-19. This will allow for effective therapeutic intervention and appropriate disease management in challenging conditions. In this study, our aim was to conduct a comprehensive review of the current literature on neutropenia during or after SARS-CoV2 infection. Furthermore, we assessed whether there have been any documented cases of immune-mediated neutropenia following COVID-19 and if the appropriate laboratory investigations have been carried out in these patients.

14.
Dent Res J (Isfahan) ; 21: 18, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476712

RESUMEN

Background: This study aimed to assess the effect of polishing versus glazing of computer-aided design-computer-aided manufacturing (CAD-CAM) ceramics on depth of wear and surface roughness of opposing composite resin. Materials and Methods: This in vitro study was conducted on 40 Z250 composite and 40 CAD-CAM ceramic specimens including Celtra Duo, Vita Mark II, e.max CAD, and Vita Suprinity ceramics. All ceramic specimens were roughened by a fine-grit bur after primary glazing to simulate an adjusted surface in the clinical setting. They were then randomly assigned to two subgroups and underwent reglazing or polishing. All composite and ceramic specimens underwent profilometry after surface treatment and prior to the wear test, and the results were recorded quantitatively. Composite specimens were then subjected to 120,000 wear cycles against ceramic specimens in a chewing simulator, and the depth of wear was measured by a scanner. Data were statistically analyzed by repeated measures two-way analysis of variance (ANOVA) and one-way ANOVA (α = 0.05). Results: Comparison of the surface roughness of composite specimens before and after the wear test revealed significant differences in both glazed Suprinity (P = 0.048) and Vita Mark II (P = 0.026) ceramics groups. The change in surface roughness after the wear test (compared with baseline) was significant in glazed (P = 0.000) and polished (P = 0.013) Vita Mark II and polished Suprinity (P = 0.037) ceramics, but this change was not significant in other ceramics (P > 0.05). The depth of wear after the wear test was not significantly different among the ceramic and composite subgroups (P > 0.05). Conclusion: Assessment of depth of wear and surface roughness of composite specimens showed that the polishing kits of CAD-CAM ceramics can serve as a suitable alternative to reglazing.

15.
Clin Exp Dent Res ; 10(3): e884, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38798053

RESUMEN

OBJECTIVES: This study compared the effects of glazing versus polishing on mechanical, optical, and surface properties of zirconia ceramics with different translucencies. MATERIALS AND METHODS: In this in vitro study, 120 bar-shaped specimens (25 × 4 × 1.2 mm) were fabricated from three different types of zirconia with different translucencies (n = 40, DD Bio ZW, ZX2, and Cube X2). After sintering, each zirconia group was randomly divided into five subgroups of control (glazing), glazing + bur abrasion, glazing + bur abrasion + polishing with EVE Diacera® kit, glazing + bur abrasion + reglazing, and glazing + bur abrasion + polishing with EVE Diacera® kit + reglazing. The specimens underwent surface roughness, hardness, flexural strength, and translucency tests, as well as X-ray diffraction (XRD) and scanning electron microscopy (SEM) for assessment of surface topography. Data were analyzed by one-way analysis of variance, Tukey test, and Pearson test (α = .05). RESULTS: Flexural strength, surface hardness, and translucency were significantly correlated with zirconia type. ZW zirconia had significantly higher flexural strength and surface hardness and significantly lower translucency than Cube X2 and ZX2 (p < .001). Surface roughness had no significant correlation with zirconia type (p = .274). Polishing created the smoothest, and bur abrasion created the roughest surface (p < .001). Flexural strength and hardness in most experimental groups were significantly lower than in the control group (p < .001). Translucency was not significantly different in bur abrasion and polishing groups, compared with the control group; however, reglazing significantly increased the translucency (p < .001). SEM micrographs confirmed the surface roughness results. XRD showed monoclinic phase only in reglazed groups. CONCLUSION: Of different surface treatments, polishing improved the surface properties and caused the smallest change in mechanical properties of zirconia with different translucencies.


Asunto(s)
Cerámica , Pulido Dental , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Circonio , Circonio/química , Pulido Dental/métodos , Cerámica/química , Dureza , Materiales Dentales/química , Resistencia Flexional , Difracción de Rayos X , Técnicas In Vitro
16.
Clin Exp Dent Res ; 10(4): e916, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38970227

RESUMEN

OBJECTIVES: This study assessed the effects of 15% and 20% carbamide peroxide (CP) on color, surface roughness, and hardness of computer-aided design/computer-aided manufacturing (CAD/CAM) dental ceramics. MATERIALS AND METHODS: This in vitro study was conducted on 120 Vita Mark II, Celtra Duo, and Suprinity CAD/CAM ceramic specimens. The ceramic specimens in each group (n = 40) were randomly assigned to two subgroups (n = 20) for polishing and glazing, and their baseline color, surface roughness (Ra), and hardness were assessed. In each subgroup, half of the specimens were exposed to 15% CP, while the other half were exposed to 20% CP. Their color change (ΔE), surface roughness, and hardness were then measured again. Surface roughness, hardness, and color were analyzed sequentially by profilometer, Vickers hardness tester, and spectrophotometer, respectively. Data were analyzed by repeated measures ANOVA, one-way ANOVA, and post hoc Bonferroni test (α = 0.05). RESULTS: The surface roughness of all groups significantly increased after bleaching treatment (p < 0.05). Surface hardness of all groups decreased after bleaching treatment, but this reduction was only significant in Vita Mark II subgroups (glazed, polished, 15%, and 20% CP). The ΔE was not clinically and visually perceivable in any group. CONCLUSION: The present results revealed that concentration of CP and type of surface treatment affected the surface properties of CAD/CAM ceramics. Type of surface treatment only affected the surface hardness of Vita Mark II ceramics (p < 0.05). Concentration of CP had a significant effect only on polished Vita Mark II.


Asunto(s)
Peróxido de Carbamida , Cerámica , Color , Diseño Asistido por Computadora , Dureza , Ensayo de Materiales , Peróxidos , Propiedades de Superficie , Peróxido de Carbamida/química , Propiedades de Superficie/efectos de los fármacos , Dureza/efectos de los fármacos , Cerámica/química , Peróxidos/química , Porcelana Dental/química , Urea/química , Urea/análogos & derivados , Urea/farmacología , Blanqueadores Dentales/química , Humanos , Técnicas In Vitro , Materiales Dentales/química , Espectrofotometría
17.
Dent Res J (Isfahan) ; 21: 44, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39376258

RESUMEN

Background: This study aimed to measure light transmittance (LT) through various thicknesses of computer-aided design/computer-aided manufacturing bleach shade ceramics and to assess the Vickers microhardness (VMH) of underlying light-cured resin cement. Materials and Methods: In this in vitro study, a total of 90 ceramic discs (VITA Mark II [VM], VITA Suprinity, and CELTRA Duo) were prepared in 0.5, 1, and 1.5 mm thicknesses. To measure LT, the Valo light-curing unit was placed in direct contact with the ceramics on the radiometer. The average LT was recorded after three measurements. In addition, 90 specimens of light-cured resin cement (Allcem Veneer) were cured in Teflon molds (0.5 mm in depth) beneath ceramic pieces. Ten specimens of resin cement were also cured without the presence of ceramic as a control group. VMH of the cement specimens was reported. The data were analyzed by one-way analysis of variance and multiple comparison tests (α =0.05) in SPSS version 17. Results: In each ceramic group, LT was negatively related to ceramic thickness (P < 0.05). At a thickness of 1.5 mm among all ceramic types, the VMH of resin cement was significantly decreased (P < 0.05). In all thicknesses, the VMH of resin cement was lower significantly than the control group, except for the thickness of 0.5 mm of VM. Conclusion: According to the results of this study, light-cured cement is not a suitable option for cementing the studied bleach shade ceramics. Furthermore, the thickness of the ceramic has a significant effect on LT (P < 0.05), unlike VMH.

18.
Front Dent ; 20: 9, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37312827

RESUMEN

Objectives: This study aimed to assess the microtensile bond strength (µTBS) of etch-and-rinse (E&R), self-etch (SE), and universal adhesives to superficial and deep dentin. Materials and Methods: In this in vitro study, 40 sound third molars were randomly divided into two main groups of superficial and deep dentin. Based on our classification, superficial dentin was right beneath the deepest occlusal groove, and deep dentin was 2mm beneath the deepest occlusal groove. Each group was divided into 4 subgroups (n=20) for application of Adper Single Bond 2 (ASB), Clearfil SE Bond (CSE), and Scotchbond Universal (SBU) in E&R and SE modes along with Charisma Smart composite resin on dentin. The specimens were incubated in distilled water at 37°C for 24 hours and their µTBS was then measured. The mode of failure was determined under a stereomicroscope at ×40 magnification. Data were analyzed by one-way ANOVA (alpha=0.05). Results: The highest µTBS belonged to the superficial dentin/SBU/E&R group. The µTBS was significantly higher in superficial dentin than deep dentin for all adhesives (P=0.005). There was no significant difference in mode of failure among the groups. Conclusion: Based on the results obtained in the present study, type of bonding agent and application mode affected µTBS. In use of universal adhesive, E&R mode can improve µTBS.

19.
Front Dent ; 20: 10, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37312832

RESUMEN

Objectives: The durability of composite restorations is directly affected by the mechanical properties of the composite. The aim of this study was to evaluate the hardness and wear resistance of self-adhesive flowable composite (SAF) in comparison with conventional flowable composites. Materials and Methods: In this in vitro study, 50 composite specimens were prepared in brass molds with 10mm ×10mm ×2mm and divided into five groups (n=10). Specimens included three conventional flowable composites (Grandio flow, Filtek flow and Admira fusion flow), one self-adhering flowable composite (SAF, Vertise flow) and a microhybrid composite (filtek z250). After polishing, the micro-hardness of the specimens was measured in a Vickers hardness device, and the specimens were then subjected to 5000, 10000, 20000, 40000, 80000 and 120000 wear cycles in a wear tester. One-way ANOVA/Games-Howell, Kruskal Wallis, and Friedman tests were used for statistical analysis. The significance level was set at P<0.05. Results: The surface micro-hardness of the SAF was significantly lower than that of the microhybrid composite (P=0.01). There was no significant difference between the surface hardness of the different tested flowable composites (P>0.05). Also, the wear resistance of the studied composites was not significantly different in various cycles (P>0.05). Conclusion: Based on our results, SAF would not be an ideal substitute for conventional flowable composites in high-stress areas.

20.
Iran J Allergy Asthma Immunol ; 22(5): 468-481, 2023 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-38085148

RESUMEN

Many studies have evaluated the possible utility of cycle threshold (Ct) values as a predictor of Coronavirus disease 2019 (COVID-19) severity and patient outcome. Given the inconsistent results, we aimed to evaluate the association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Ct values and disease severity, inflammatory markers, and outcomes in Iranian patients with COVID-19. A retrospective study of 528 patients with COVID-19 hospitalized from September 2020 to October 2021 was conducted. Demographic, clinical, and laboratory data of patients were retrieved from electronic medical records. Ct values were analyzed as a continuous variable after subcategorizing into 3 groups: low (Ct values<20), medium (Ct values 20 to 30), and high (Ct values>30). Of the 528 patients (45.1% female) aged 13 to 97 years, 109 patients had low Ct values, 312 patients had medium, and 107 patients had high Ct values. Patients with low Ct values were more likely to present with critical COVID-19, require invasive mechanical ventilation and develop complications such as acute respiratory distress syndrome and pneumonia. Furthermore, patients with low or medium Ct values were more likely to die compared to patients with high Ct values. Multivariate analysis showed that patients with low or medium Ct values were more likely to have severe COVID-19 compared with patients with high Ct values. The multivariate analysis also showed a higher risk of mortality in patients with low Ct values compared to patients with high Ct values, although this was not statistically significant. Our findings revealed that Ct values were an independent predictor of COVID-19 severity. The risk of mortality was higher in patients with low Ct values. However, further investigation is needed to address the correlation between Ct values and inflammatory factors.


Asunto(s)
COVID-19 , Humanos , Femenino , Masculino , SARS-CoV-2 , Estudios Retrospectivos , Irán/epidemiología , Biomarcadores
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