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1.
Dent Mater ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39277488

RESUMO

BACKGROUND: Dental resin composites' performance is intricately linked to their polymerisation shrinkage characteristics. This study compares polymerisation shrinkage using advanced 3D micro-computed tomography (micro-CT) and traditional 2D linear assessments. It delves into the crucial role of filler content on shrinkage and the degree of conversion in dental resin composites, providing valuable insights for the field. METHODS: Five experimental dental composite materials were prepared with increasing filler contents (55-75 wt%) and analysed using either 3D micro-CT for volumetric shrinkage or a custom-designed linometer for 2D linear shrinkage. The degree of conversion was assessed using Optical Photothermal Infrared (O-PTIR) and Fourier-Transform Infrared (FTIR) spectroscopy. Light transmittance through a 2-mm layer was evaluated using a NIST-calibrated spectrometer. Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDX) examined surface morphology and elemental distribution. Correlation between the investigated parameters was determined using Spearman correlation analyses. RESULTS: The study found significant differences in polymerisation-related properties among different filler content categories, with volumetric shrinkage consistently demonstrating higher mean values than linear shrinkage across most groups. Volumetric shrinkage decreased with increasing curing depth, showing no direct correlation between filler content and shrinkage levels at different curing depths. The results highlighted a strong negative correlation between filler content and degree of conversion, volumetric and linear shrinkage, as well as maximum shrinkage rate. Light transmittance showed a moderate correlation with the filler content and a weak correlation with other tested parameters. CONCLUSIONS: This study underscores the importance of considering both volumetric and linear shrinkage in the design and analysis of dental composite materials. The findings advocate optimising filler content to minimise shrinkage and enhance material performance. Integrating micro-CT and O-PTIR techniques offers novel insights into dental composites' polymerisation behaviour, providing a foundation for future research to develop materials with improved clinical outcomes.

3.
Clin Oral Investig ; 28(8): 430, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012388

RESUMO

OBJECTIVES: This in vitro study examined the marginal integrity of experimental composite materials doped with bioactive glass (BG). MATERIALS AND METHODS: Class-II MOD cavities were prepared and restored with one of the following composite materials: a commercial composite material as a reference (Filtek Supreme XTE), an experimental composite doped with BG 45S5 (C-20), and an experimental composite doped with a fluoride-containing BG (F-20). Six experimental groups (n = 8) were used, as each of the three composites was applied with (+) or without (-) a universal adhesive (Adper Scotchbond Multipurpose). All specimens were subjected to thermocycling (10,000 x, 5-55 °C) and then additionally stored in artificial saliva for eight weeks. Scanning electron micrographs of the mesial and the distal box were taken at three time points (initial, after thermocycling, and after eight weeks of storage in artificial saliva). The margins were classified as "continuous" and "non-continuous" and the percentage of continuous margins (PCM) was statistically analyzed (α = 0.05). RESULTS: In most experimental groups, thermocycling led to a significant decrease in PCM, while the additional 8-week aging had no significant effect. F-20 + performed significantly better (p = 0.005) after 8 weeks storage in artificial saliva than the reference material with adhesive, while no statistically significant differences were observed at the other two time points. C-20 + exhibited significantly better PCM than the reference material with adhesive after thermocycling (p = 0.026) and after 8 weeks (p = 0.003). CONCLUSIONS: Overall, the experimental composites with BG showed at least as good marginal adaptation as the commercial reference, with an indication of possible re-sealing of marginal gaps. CLINICAL RELEVANCE: Maintaining or improving the marginal integrity of composite restorations is important to prevent microleakage and its likely consequences such as pulp irritation and secondary caries.


Assuntos
Resinas Compostas , Adaptação Marginal Dentária , Restauração Dentária Permanente , Vidro , Teste de Materiais , Microscopia Eletrônica de Varredura , Saliva Artificial , Propriedades de Superfície , Resinas Compostas/química , Técnicas In Vitro , Vidro/química , Restauração Dentária Permanente/métodos , Saliva Artificial/química , Humanos , Preparo da Cavidade Dentária , Cerâmica/química , Cimentos de Resina/química , Fluoretos/química
4.
Nat Commun ; 15(1): 5149, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890299

RESUMO

Telomeres are the protective nucleoprotein structures at the end of linear eukaryotic chromosomes. Telomeres' repetitive nature and length have traditionally challenged the precise assessment of the composition and length of individual human telomeres. Here, we present Telo-seq to resolve bulk, chromosome arm-specific and allele-specific human telomere lengths using Oxford Nanopore Technologies' native long-read sequencing. Telo-seq resolves telomere shortening in five population doubling increments and reveals intrasample, chromosome arm-specific, allele-specific telomere length heterogeneity. Telo-seq can reliably discriminate between telomerase- and ALT-positive cancer cell lines. Thus, Telo-seq is a tool to study telomere biology during development, aging, and cancer at unprecedented resolution.


Assuntos
Envelhecimento , Neoplasias , Telômero , Humanos , Telômero/genética , Telômero/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Envelhecimento/genética , Telomerase/genética , Telomerase/metabolismo , Linhagem Celular Tumoral , Encurtamento do Telômero/genética , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Alelos
5.
NPJ Genom Med ; 9(1): 18, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429302

RESUMO

CELSR3 codes for a planar cell polarity protein. We describe twelve affected individuals from eleven independent families with bi-allelic variants in CELSR3. Affected individuals presented with an overlapping phenotypic spectrum comprising central nervous system (CNS) anomalies (7/12), combined CNS anomalies and congenital anomalies of the kidneys and urinary tract (CAKUT) (3/12) and CAKUT only (2/12). Computational simulation of the 3D protein structure suggests the position of the identified variants to be implicated in penetrance and phenotype expression. CELSR3 immunolocalization in human embryonic urinary tract and transient suppression and rescue experiments of Celsr3 in fluorescent zebrafish reporter lines further support an embryonic role of CELSR3 in CNS and urinary tract formation.

6.
Kidney Int ; 105(6): 1212-1220, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38514000

RESUMO

Accurate assessment of the glomerular filtration rate (GFR) is crucial for researching kidney disease in rats. Although validation of methods that assess GFR is crucial, large-scale comparisons between different methods are lacking. Both transcutaneous GFR (tGFR) and a newly developed estimated GFR (eGFR) equation by our group provide a low-invasive approach enabling repeated measurements. The tGFR is a single bolus method using FITC-labeled sinistrin to measure GFR based on half-life of the transcutaneous signal, whilst the eGFR is based on urinary sinistrin clearance. Here, we retrospectively compared tGFR, using both 1- and 3- compartment models (tGFR_1c and tGFR_3c, respectively) to the eGFR in a historic cohort of 43 healthy male rats and 84 male rats with various models of chronic kidney disease. The eGFR was on average considerably lower than tGFR-1c and tGFR-3c (mean differences 855 and 216 µL/min, respectively) and only 20 and 47% of measurements were within 30% of each other, respectively. The relative difference between eGFR and tGFR was highest in rats with the lowest GFR. Possible explanations for the divergence are problems inherent to tGFR, such as technical issues with signal measurement, description of the signal kinetics, and translation of half-life to tGFR, which depends on distribution volume. The unknown impact of isoflurane anesthesia used in determining mGFR remains a limiting factor. Thus, our study shows that there is a severe disagreement between GFR measured by tGFR and eGFR, stressing the need for more rigorous validation of the tGFR and possible adjustments to the underlying technique.


Assuntos
Modelos Animais de Doenças , Taxa de Filtração Glomerular , Insuficiência Renal Crônica , Animais , Masculino , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/urina , Insuficiência Renal Crônica/diagnóstico , Ratos , Rim/fisiopatologia , Ratos Sprague-Dawley , Estudos Retrospectivos , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/farmacocinética , Fluoresceína-5-Isotiocianato/administração & dosagem , Reprodutibilidade dos Testes , Eliminação Renal/fisiologia , Fluoresceínas , Oligossacarídeos
7.
Sci Rep ; 14(1): 6315, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491076

RESUMO

The aim was to investigate the influence of endodontic irrigation solutions and protocols on the micro-tensile bond strength (µTBS) to dentin using an etch-and-rinse (ER) or self-etch (SE) adhesive approach. Eighty extracted human molars were ground to dentin. After pretreating for 27 min (21 min-3 min-3 min) with five different endodontic irrigation protocols (Group 1: NaOCl-EDTA-NaOCl; Group 2: NaOCl-NaOCl-EDTA; Group 3: NaOCl-NaCl-NaOCl; Group 4: Dual Rinse-Dual Rinse-Dual Rinse; Group 5: NaCl-NaCl-NaCl), an ER (Optibond FL, Kerr) or a SE (Clearfil SE Bond, Kuraray) adhesive system was applied. After light-curing, composite build-ups were made and cut into dentin-composite sticks. µTBS and failure modes were analyzed. Nonparametric statistical analyses (α = 0.05) were performed for comparison of the five groups within each type of adhesive as well as between the two adhesive systems used. The use of an ER instead of a SE adhesive system resulted in significantly higher µTBS for all irrigation protocols except for group 1 (NaOCl-EDTA-NaOCl) and 2 (NaOCl-NaOCl-EDTA). A statistical difference between the five different endodontic irrigation protocols was only found within the SE adhesive group, where group 1 (NaOCl-EDTA-NaOCl) achieved highest values. The use of an ER adhesive system cancels out the effect of the endodontic irrigation solution. The highest µTBS was achieved when using a NaOCl-EDTA-NaOCl-irrigation protocol in combination with Clearfil SE Bond, which shows that the selection of the endodontic irrigation should match the corresponding SE adhesive system.


Assuntos
Cloreto de Sódio , Hipoclorito de Sódio , Humanos , Ácido Edético/farmacologia , Ácido Edético/química , Hipoclorito de Sódio/farmacologia , Hipoclorito de Sódio/química , Cloreto de Sódio/farmacologia , Dentina/química , Adesivos Dentinários/química , Teste de Materiais , Resistência à Tração
8.
Ocul Surf ; 31: 1-8, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38049032

RESUMO

PURPOSE: This double-blinded randomized clinical trial aimed to evaluate the efficacy of injecting allogeneic adipose-derived mesenchymal stem cells (ASCs) into the lacrimal gland (LG) for the treatment of dry eye disease (DED) secondary to Sjögren's syndrome (SS). METHODS: Fifty-four participants with severe DED secondary to SS were included and allocated to either ASCs (n = 20), vehicle (n = 20), or a non-randomized observation group (n = 14). The intervention groups received a single injection of either ASCs or an active comparator (vehicle, Cryostor® CS10) into the LG in one eye, while the observation group received lubricating eye drops only. The primary outcome measure was changes in Ocular Surface Disease Index (OSDI) score and secondary outcome measures were non-invasive tear break-up time, tear meniscus height, Schirmer's test, and Oxford score within a 12-month follow-up. RESULTS: A significant reduction in OSDI score was observed in the ASCs and vehicle groups compared to the observation group. In addition, the ASCs group demonstrated a significant increase in non-invasive tear break-up time compared to the vehicle group at the 4-week follow-up and to the observation group at the 12-month follow-up. A significant improvement in ocular surface staining, tear osmolarity, and Schirmer test score from baseline was also observed in the ASCs group; however, these changes were not significant compared to the other groups. CONCLUSION: Improvement of subjective and objective signs and symptoms of DED was observed in both intervention groups following injection into the LG compared to the observation group. Future studies should investigate the mode-of-action of both injection treatments.


Assuntos
Síndromes do Olho Seco , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Síndrome de Sjogren , Humanos , Síndrome de Sjogren/complicações , Síndrome de Sjogren/terapia , Síndrome de Sjogren/diagnóstico , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/terapia , Síndromes do Olho Seco/diagnóstico , Lágrimas/metabolismo
9.
J Appl Anim Welf Sci ; : 1-14, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37818802

RESUMO

This study researched end-of-life (EoL) decision-making processes in small animal practices in the Netherlands, focusing on strategies veterinarians contemplate during this process. Fourteen veterinarians were interviewed about animal end-of-life decision-making. The results of these interviews show that the decision-making process consists of three steps. The first step is to assess the animal's health and welfare. During the second step, veterinarians consider the position of the owner. Based on steps 1 and 2, veterinarians decide in step 3 whether their advice is to a) euthanize or b) contemplate one or more strategies to come to a decision or potentially alter the decision. These results can support members of the veterinary profession to reflect on their decision-making process. If veterinarians know what strategies their peers use to deal with EoL situations, this can help to reduce the stress they experience in such situations. In addition, veterinarians may find inspiration for new strategies in the study results. For the veterinary profession itself, the current results can be used as a starting point for describing best practices for EoL decision-making in small animal practice.

10.
BMC Oral Health ; 23(1): 569, 2023 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-37574544

RESUMO

BACKGROUND: Reducing the necessary time to restore primary teeth improves the cooperation of paediatric patients. This study aimed to investigate the marginal integrity of restorations prepared with a bulk-fill resin-based composite (RBC) containing additional fragmentation chain transfer (AFCT) compared to a conventional RBC when light cured with a rapid high-irradiance (3 s) and a regular (10 s) curing mode. METHODS: Forty class-II cavities were prepared in 40 primary molars. The molars were randomly divided into four groups based on the applied light-curing modes (regular: 10 s @ 1200 mW/cm2 or high-irradiance: 3 s @ 3000 mW/cm2) and the used restorative material (AFCT-containing bulk-fill RBC "Power Fill" or AFCT-free conventional RBC "Prime"). After thermo-mechanical loading, the marginal integrity was analysed using scanning electron microscopy. A beta regression model and pairwise comparisons were used to statistically analyse the data. RESULTS: The mean marginal integrity (% ± SD) of the restorations for each group was as follows: Power Fill (10 s: 79.7 ± 15.6) (3 s: 77.6 ± 11.3), Prime (10 s: 69.7 ± 11.1) (3 s: 75.0 ± 9.7). The difference between the RBCs for the same light-curing mode was statistically significant (p ≤ 0.05). The difference between the light-curing modes for the same RBC was not statistically significant (p ˃ 0.5). CONCLUSIONS: AFCT-containing bulk-fill RBC "Power Fill" achieves similar marginal integrity when light-cured with either high-irradiance or regular light-curing modes. "Power Fill" achieves better marginal integrity than the conventional RBC "Prime" regardless of the applied light-curing mode.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Criança , Humanos , Resinas Compostas/uso terapêutico , Lâmpadas de Polimerização Dentária , Materiais Dentários , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Dente Decíduo
11.
Swiss Dent J ; 133(7-8): 489-495, 2023 07 10.
Artigo em Alemão | MEDLINE | ID: mdl-37386907

RESUMO

The restorative treatment of dental hard tissue loss, e.g., due to erosion, and the rehabilitation of the original vertical bite dimension confronts the dentist with problems when implementing the therapy. Traditionally, this therapy is conducted with laboratory-fabricated workpieces made of ceramics which usually require a preparation of the remaining tooth substance and also causes high costs for the patient. Therefore, alternative methods should be considered. This article presents the use of direct adhesive composite restorations as a way of reconstructing a dentition severely altered by erosion. To reconstruct the occlusal surfaces, transfer splints are used that are made on the basis of individual wax-up models. The procedure described is a well-researched and proven method for restoring teeth with erosion-related loss of hard tooth substance. As with all new procedures, there will be a certain learning curve for the practical dentist after which high-quality restorations can be implemented with this technique.


Assuntos
Exostose , Atrito Dentário , Desgaste dos Dentes , Humanos , Desgaste dos Dentes/terapia , Cerâmica , Oclusão Dentária
12.
J Funct Biomater ; 14(6)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37367262

RESUMO

The aim of the study was to evaluate microhardness, mass changes during 1-year water immersion, water sorption/solubility, and calcium phosphate precipitation of experimental composites functionalized with 5-40 wt% of two types of bioactive glass (BG): 45S5 or a customized low-sodium fluoride-containing formulation. Vickers microhardness was evaluated after simulated aging (water storage and thermocycling), water sorption and solubility were tested according to ISO 4049, and calcium phosphate precipitation was studied by scanning electron microscopy, energy dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. For the composites containing BG 45S5, a significant reduction in microhardness was observed with increasing BG amount. In contrast, 5 wt% of the customized BG resulted in statistically similar microhardness to the control material, while higher BG amounts (20 and 40 wt%) resulted in a significant improvement in microhardness. Water sorption was more pronounced for composites containing BG 45S5, increasing 7-fold compared to the control material, while the corresponding increase for the customized BG was only 2-fold. Solubility increased with higher amounts of BG, with an abrupt increase at 20 and 40 wt% of BG 45S5. Calcium phosphate was precipitated by all composites with BG amounts of 10 wt% or more. The improved properties of the composites functionalized with the customized BG indicate better mechanical, chemical, and dimensional stability without compromising the potential for calcium phosphate precipitation.

13.
Int Dent J ; 73(6): 881-888, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37385864

RESUMO

OBJECTIVE: The aim of this research was to investigate the effect of simplified adhesive strategies (self-etch vs selective enamel etch and 10- vs 20-second adhesive application time) on the marginal integrity in primary molars. METHODS: Forty deep class-II cavities were prepared in 40 extracted primary molars. The molars were divided into 4 groups based on the applied universal adhesive strategy as follows: groups 1 and 2: selective enamel etch with 20- or 10-second application time and groups 3 and 4: self-etch with 20- or 10-second application time. All cavities were restored with a sculptable bulk-fill composite restoration. The restorations underwent a thermomechanical loading (TML, 5-50 °C, 2-minute dwelling time, ×1000; 400,000 loading cycles, 1.7 Hz, 49 N). Marginal analysis before and after TML was conducted with scanning electron microscopy and the marginal integrity of each restoration was calculated as a percentage of continuous margins. A beta regression model was adopted to statistically analyse the data with a consequent pairwise comparison. RESULTS: The mean marginal integrity (% ± SD) of the restorations for each tested adhesive strategy after TML was as follows: selective enamel etch/20 seconds = 85.4 ± 3.9, self-etch/20 seconds = 85.3 ± 5.2, self-etch/10 seconds = 80.1 ± 8.2, and selective enamel etch/10 seconds = 80.0 ± 8.5. The difference between both adhesive strategies was not statistically significant at the same application time. The difference between both application times within the same adhesive strategy was statistically significant (P ≤ .01). CONCLUSIONS: Universal adhesives applied either in selective enamel etch or in self-etch mode result in comparable marginal integrities when restoring class-II cavities in primary molars. Shortened adhesive application time (10 seconds) could lead to a reduction in the marginal integrity in comparison to the recommended application time of 20 seconds.


Assuntos
Colagem Dentária , Cárie Dentária , Humanos , Resinas Compostas/uso terapêutico , Cimentos Dentários/uso terapêutico , Cimentos de Resina/uso terapêutico , Teste de Materiais , Cárie Dentária/prevenção & controle , Dente Decíduo , Adaptação Marginal Dentária , Adesivos Dentinários/uso terapêutico , Restauração Dentária Permanente
14.
Am J Dent ; 36(3): 118-122, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37364188

RESUMO

PURPOSE: To investigate the effect of over-etching and subsequent use of different adhesive application approaches including active, double, preheated, and ultrasonic application on dentin bond strength. METHODS: Dentin specimens from sound human third molars were prepared and allocated into six groups (n= 10 per group). In Group 1 (negative control), the dentin specimens were over-etched with phosphoric acid for 30 seconds, and a two-step etch-and-rinse adhesive (Prime & Bond XP; Dentsply Sirona) was applied for 20 seconds according to the manufacturer's instructions. In test Groups 2-5, the application of the adhesive varied: In Group 2, the adhesive was actively rubbed into the dentin surface, whereas in Group 3, a second adhesive layer was applied after light-curing of the first one. In Group 4, the adhesive was heated to 68°C prior to application, and in Group 5, the adhesive was ultrasonically activated. Acid-etching for 15 seconds and adhesive application for 20 seconds was performed in the positive control group (Group 6) according to the manufacturer's instructions. After light-curing and composite build-up [Ceram.x Spectra ST (HV); Dentsply Sirona], microtensile bond strength and fracture types were determined. Data were statistically analyzed by Kruskal-Wallis rank test, followed by post-hoc pairwise comparisons using Conover tests and P-value adjustment according to Holm (α= 0.05). RESULTS: Active, double, preheated, or ultrasonic adhesive application showed no significant effect on dentin bond strength when compared to the control groups. Predominantly adhesive failures were observed in all groups. CLINICAL SIGNIFICANCE: A modification of adhesive application by using active, double, preheated, or ultrasonic application does not improve bonding to accidentally over-etched dentin.


Assuntos
Colagem Dentária , Cimentos Dentários , Humanos , Adesivos Dentinários/química , Resinas Compostas/química , Dentina , Resistência à Tração , Teste de Materiais , Cimentos de Resina/química
15.
Br J Clin Pharmacol ; 89(10): 3016-3025, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37194167

RESUMO

AIMS: Carboplatin is generally dosed based on a modified Calvert formula, in which the Cockcroft-Gault-based creatinine clearance (CRCL) is used as proxy for the glomerular filtration rate (GFR). The Cockcroft-Gault formula (CG) overpredicts CRCL in patients with an aberrant body composition. The CT-enhanced estimate of RenAl FuncTion (CRAFT) was developed to compensate for this overprediction. We aimed to evaluate whether carboplatin clearance is better predicted by CRCL based on the CRAFT compared to the CG. METHODS: Data of four previously conducted trials was used. The CRAFT was divided by serum creatinine to derive CRCL. The difference between CRAFT- and CG-based CRCL was assessed by population pharmacokinetic modelling. Furthermore, the difference in calculated carboplatin dose was assessed in a heterogeneous dataset. RESULTS: In total, 108 patients were included in the analysis. Addition of the CRAFT- and CG-based CRCL as covariate on carboplatin clearance led, respectively, to an improved model fit with a 26-point drop in objective function value and a worsened model fit with an increase of 8 points. In 19 subjects with serum creatinine <50 µmol/L, the calculated carboplatin dose was 233 mg higher using the CG. CONCLUSIONS: Carboplatin clearance is better predicted by CRAFT vs. CG-based CRCL. In subjects with low serum creatinine, the calculated carboplatin dose using CG exceeds the dose using CRAFT, which might explain the need for dose capping when using the CG. Therefore, the CRAFT might be an alternative for dose capping while still dosing accurately.


Assuntos
Antineoplásicos , Humanos , Carboplatina , Creatinina , Taxa de Filtração Glomerular , Rim/fisiologia , Tomografia Computadorizada por Raios X
16.
Clin Oral Investig ; 27(6): 3169-3180, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36869923

RESUMO

OBJECTIVES: To assess the behavior of dual-cure and conventional bulk-fill composite materials on real-time linear shrinkage, shrinkage stress, and degree of conversion. MATERIALS AND METHODS: Two dual-cure bulk-fill materials (Cention, Ivoclar Vivadent (with ion-releasing properties) and Fill-Up!, Coltene) and two conventional bulk-fill composites (Tetric PowerFill, Ivoclar Vivadent; SDR flow + , Dentsply Sirona) were compared to conventional reference materials (Ceram.x Spectra ST (HV), Dentsply Sirona; X-flow; Dentsply Sirona). Light curing was performed for 20 s, or specimens were left to self-cure only. Linear shrinkage, shrinkage stress, and degree of conversion were measured in real time for 4 h (n = 8 per group), and kinetic parameters were determined for shrinkage stress and degree of conversion. Data were statistically analyzed by ANOVA followed by post hoc tests (α = 0.05). Pearson's analysis was used for correlating linear shrinkage and shrinkage force. RESULTS: Significantly higher linear shrinkage and shrinkage stress were found for the low-viscosity materials compared to the high-viscosity materials. No significant difference in degree of conversion was revealed between the polymerization modes of the dual-cure bulk-fill composite Fill-Up!, but the time to achieve maximum polymerization rate was significantly longer for the self-cure mode. Significant differences in degree of conversion were however found between the polymerization modes of the ion-releasing bulk-fill material Cention, which also exhibited the significantly slowest polymerization rate of all materials when chemically cured. CONCLUSIONS: While some of the parameters tested were found to be consistent across all materials studied, heterogeneity increased for others. CLINICAL RELEVANCE: With the introduction of new classes of composite materials, predicting the effects of individual parameters on final clinically relevant properties becomes more difficult.


Assuntos
Resinas Compostas , Cinética , Polimerização , Teste de Materiais , Resinas Compostas/química
17.
Nature ; 614(7949): 767-773, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36755096

RESUMO

Cancers arise through the accumulation of genetic and epigenetic alterations that enable cells to evade telomere-based proliferative barriers and achieve immortality. One such barrier is replicative crisis-an autophagy-dependent program that eliminates checkpoint-deficient cells with unstable telomeres and other cancer-relevant chromosomal aberrations1,2. However, little is known about the molecular events that regulate the onset of this important tumour-suppressive barrier. Here we identified the innate immune sensor Z-DNA binding protein 1 (ZBP1) as a regulator of the crisis program. A crisis-associated isoform of ZBP1 is induced by the cGAS-STING DNA-sensing pathway, but reaches full activation only when associated with telomeric-repeat-containing RNA (TERRA) transcripts that are synthesized from dysfunctional telomeres. TERRA-bound ZBP1 oligomerizes into filaments on the outer mitochondrial membrane of a subset of mitochondria, where it activates the innate immune adapter protein mitochondrial antiviral-signalling protein (MAVS). We propose that these oligomerization properties of ZBP1 serve as a signal amplification mechanism, where few TERRA-ZBP1 interactions are sufficient to launch a detrimental MAVS-dependent interferon response. Our study reveals a mechanism for telomere-mediated tumour suppression, whereby dysfunctional telomeres activate innate immune responses through mitochondrial TERRA-ZBP1 complexes to eliminate cells destined for neoplastic transformation.


Assuntos
Replicação do DNA , Mitocôndrias , Transdução de Sinais , Telômero , Humanos , DNA/biossíntese , DNA/genética , DNA/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias/genética , Neoplasias/patologia , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Telômero/genética , Telômero/metabolismo , Interferons , Imunidade Inata , Autofagia
18.
Porcine Health Manag ; 9(1): 2, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36642740

RESUMO

BACKGROUND: In pig husbandry, most piglets receive an intramuscular injection with iron around three days of age for the prevention of hypochromic, microcytic anaemia. In recent years an increased interest is noted for needle-free injections, because of efficiency and safety for man and animal. This study aims to support the evidence on efficacy to extent the registration of a commercial iron supplement with a needle-free administration application. To this aim the study has two objectives: 1) to determine the effect of needle-free injection of the iron supplement on the mean blood Haemoglobin level at weaning, as primary outcome, and mean Haematocrit and mean Body weight of pigs at weaning as secondary outcome compared to no treatment, as main determinant of iron deficiency anaemia in piglets at time of weaning; 2) to compare the effects of needle-free administration of the iron supplement with regular injection by needle, with regard to the course over time of Haemoglobin, Haematocrit, piglet growth and the differentiated haematological and serum iron parameters. METHODS: A double blind randomized controlled trial was conducted with 72 piglets, 8 piglets per litter from 9 litters. At three days of age pigs were selected, based on body weight, and random allocated to three study groups: a) control non-treated group (2 pigs per litter, 18 in total), b) a group with regular iron injection by needle injection (3 pigs per litter, 27 in total), c) a group that received iron by needle-free injection (3 pigs per litter, 27 in total). At four points in time (day 3, 14, 26 and 40) piglets were weighed and bled to analyse the dynamics of red blood counts and haematological parameters as well as serum iron parameters. The primary outcome parameter was the Haemoglobin (Hb) level on day 26. Of secondary importance were Haematocrit (Ht) and body weight (BW) at weaning and parameters with tertiary importance were the course of Hb, Ht and differentiated red blood cell parameters, serum iron, iron binding capacity and iron saturation. In the statistical analyses, linear mixed effect regression modelling was used to account for repeated measures within litters and pigs. RESULTS: The analyses showed that needle-free administration was as efficacious to prevent iron deficiency anaemia at day 26 as administration using regular needle injection, compared to the control group. The mean level of Hb and Ht of pigs in the needle and needle-free group did not differ significantly. No side effects were observed. CONCLUSION: It is concluded that needle-free iron administration of the tested product is as efficacious as regular administration by needle injection.

19.
J Med Genet ; 60(6): 587-596, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36379543

RESUMO

BACKGROUND: SHROOM4 is thought to play an important role in cytoskeletal modification and development of the early nervous system. Previously, single-nucleotide variants (SNVs) or copy number variations (CNVs) in SHROOM4 have been associated with the neurodevelopmental disorder Stocco dos Santos syndrome, but not with congenital anomalies of the urinary tract and the visceral or the cardiovascular system. METHODS: Here, exome sequencing and CNV analyses besides expression studies in zebrafish and mouse and knockdown (KD) experiments using a splice blocking morpholino in zebrafish were performed to study the role of SHROOM4 during embryonic development. RESULTS: In this study, we identified putative disease-causing SNVs and CNVs in SHROOM4 in six individuals from four families with congenital anomalies of the urinary tract and the anorectal, cardiovascular and central nervous systems (CNS). Embryonic mouse and zebrafish expression studies showed Shroom4 expression in the upper and lower urinary tract, the developing cloaca, the heart and the cerebral CNS. KD studies in zebrafish larvae revealed pronephric cysts, anomalies of the cloaca and the heart, decreased eye-to-head ratio and higher mortality compared with controls. These phenotypes could be rescued by co-injection of human wild-type SHROOM4 mRNA and morpholino. CONCLUSION: The identified SNVs and CNVs in affected individuals with congenital anomalies of the urinary tract, the anorectal, the cardiovascular and the central nervous systems, and subsequent embryonic mouse and zebrafish studies suggest SHROOM4 as a developmental gene for different organ systems.


Assuntos
Sistema Cardiovascular , Sistema Urinário , Gravidez , Feminino , Humanos , Animais , Camundongos , Peixe-Zebra/genética , Variações do Número de Cópias de DNA , Morfolinos , Sistema Urinário/anormalidades , Sistema Nervoso Central
20.
Bioengineering (Basel) ; 9(12)2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36550966

RESUMO

The accumulation of caries-preventive compounds on sound enamel is crucial in order to improve the inhibition of carious lesion initiation. The aim of this research was to investigate the initial accumulation of cerium, oligopeptide p11-4, and fluoride from NaF or amine fluoride (AmF) on sound enamel in vitro by means of energy dispersive X-ray spectroscopy (EDX). Polished bovine enamel specimens (n = 120 from 60 teeth) were fabricated. Out of these, 12 specimens each were treated with CeCl3 (cerium(III) chloride heptahydrate 25%), oligopeptide p11-4 (Curodont Repair, Credentis), NaF (10,000 ppm F−), AmF (amine fluoride, Elmex Fluid, CP-GABA GmbH, 10,000 ppm F−), or Aqua demin (control). After rinsing with water, the surface elemental composition (Ce, N, F, Ca, P, O, Na, Mg) was measured (EDX; EDAX Octane Elect detector, APEX v2.0), expressed in atomic percent (At%) and analyzed (non-parametric statistics, α = 0.05, error rates method). Another 12 specimens per treatment group were fabricated and used for analyzing accumulation in cross-sections with EDX linescans and two-dimensional EDX-mappings. The surface median atomic percent of cerium (At%Ce) was 0.8 for CeCl3, but no Ce was found for any other group. N, specifically for oligopeptide p11-4, could not be detected. Fluorine could only be detected on fluoridated surfaces. The median atomic percent of fluorine (At%F) was 15.2 for NaF and 17.0 for AmF. The Ca/P ratio increased significantly compared to the control following the application of NaF and AmF (p < 0.001), but decreased significantly for CeCl3 (p < 0.001). In cross-sectioned specimens of the CeCl3-group, 12.5% of the linescans revealed cerium at the enamel surface, whereas 83.3% of the NaF linescans and 95.8% of the AmF linescans revealed fluorine at the enamel surface. Following the application of oligopeptide p11-4, no traces of N were detectable. In the depth of the samples, no signal was detected for any of the corresponding elements exceeding the background noise. Cerium and fluorine (from both NaF and AmF), but not the oligopeptide p11-4, precipitated on sound enamel.

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