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1.
J Clin Exp Dent ; 16(4): e494-e502, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38725814

RESUMO

Background: The aim was to assess the consequence of different printing orientation on the marginal misfit and internal gap of 3-unit interim fixed partial denture manufactured by two different additive manufacturing technologies compared to milling technique. Material and Methods: Three-unit interim fixed partial denture (FPD) was designed by using exocad software (Dental CAD 3.0 Galway) in the format of standard tessellation language (STL) , which was transferred to a nesting software (PreForm) and printed by A Next Dent C&B resin liquid (NextDent; Soesterberg, Neitherland) by using two printing technologies; stereolithography (SLA, n=30) and digital light processing (DLP, n=30) with 3 different orientations (occlusal direction [0°] ,buccal direction [90°] & lingual direction [270°]) for each technology (n=10). Additionally, a control group was milled (CAD/Milling, n=10) from DC PMMA A1 Disc (White peaks dental solutions; Gmbh& co., Germany). A Microcomputed tomography was used to measure the marginal misfit and internal gap for each specimen in 12 different points. The average value of the marginal and internal gaps measurements was calculated, and one-way ANOVA was used for the comparison between groups. Results: SLA printing technology showed a similar result to CAD/Milling with all different printing orientations tested. DLP printing technology showed the highest gap values within all the printing orientations with significant difference (p< 0.001) with the CAD/Milling and SLA. Conclusions: Regarding the trueness of the interim FPDs, SLA was a promising technology for its superior adaptation. Marginal misfit and Internal gap for DLP printing technology limiting the use of that technology as it exceeded the acceptable clinical range. Key words:3D Printing, Microcomputed topography, Marginal Gap, Internal Misfit.

2.
J Clin Exp Dent ; 16(4): e406-e415, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38725822

RESUMO

Background: The aim was to evaluate the effect of different irrigation protocols and antioxidants application on the shear bond strength (SBS) of two different adhesive systems to deep coronal dentin at different temperature. Material and Methods: One hundred and twenty human premolar teeth were cut longitudinally in two halves, then the prepared specimens were allocated into four main groups according to the irrigation protocols; Distilled water (control), Sodium hypochlorite (NaOCl) + Ethylenediamine Tetra-acetic Acid (EDTA), and NaOCl + Editronate (HEDP), two subgroups according to irrigation solutions temperature; 4°C and 37°C, two divisions according to grape seed extract (GSE) application (with and without), and two subdivisions according to the applied adhesive systems; OptiBond-All-In-One (OPT) and ScotchBond Universal (SBU). Adhesives were applied in self-etch (SE) mode and resin composite material discs were built. Specimens were kept in distilled water for 24-h at 37°C before SBS testing. Four-way ANOVA and Tukey HSD tests were used for data analysis (α=0.05). Results: 4°C irrigants solution temperature showed the least significant SBS values, distilled water group showed significantly higher SBS values compared to NaOCl + EDTA and NaOCl + HEDP groups respectively. GSE application improved dentin bond strength significantly within each adhesive. Conclusions: Increasing the temperature of the irrigation solutions has significantly enhanced the SBS of coronal dentin. Antioxidants application following different irrigation protocols has improved the SBS. Key words:Irrigation protocols, temperature, bond strength, coronal dentin, antioxidant, adhesive systems.

3.
BMC Oral Health ; 24(1): 307, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443910

RESUMO

STATEMENT OF PROBLEM: CAD/CAM occlusal veneers have been developed for minimally invasive prosthetic restoration of eroded teeth. Marginal adaptation and fracture resistance are crucial for the long-term survivability and clinical success of such restorations. Virgilite-based lithium disilicate glass-ceramic is a newly introduced material with claims of high strength. However, constructing occlusal veneers from this material of varying thickness has not been investigated. PURPOSE: The current study aimed to assess the impact of CAD/CAM occlusal veneer thickness and materials on marginal adaptation and fracture resistance. MATERIALS AND METHODS: Thirty-two occlusal veneers were constructed and divided into two groups (n = 16) based on the CAD/CAM material into Brilliant Crios and CEREC Tessera. Each group was further subdivided into two subgroups (n = 8) according to the thickness: 0.6 and 0.9 mm. Occlusal veneers were bonded to epoxy resin dies. The marginal gap was evaluated before and after thermodynamic aging. Fracture resistance and failure mode were evaluated for the same samples after aging. Marginal adaptation was analyzed using the Mann-Whitney U test. Fracture resistance was analyzed using Weibull analysis (α = 0.05). RESULTS: The marginal gap was significantly increased following thermodynamic aging for tested groups (P < 0.001). CEREC Tessera showed a significantly higher marginal gap than Brilliant Crios before and after aging for both thicknesses (P < 0.05). CEREC Tessera recorded lower significant fracture load values compared to Brilliant Crios (P < 0.05). CONCLUSIONS: Both CEREC Tessera and Brilliant Crios demonstrated clinically accepted marginal gap values. All groups showed fracture resistance values higher than the average masticatory forces in the premolar region except for 0.6 mm CEREC Tessera. CLINICAL IMPLICATIONS: Reinforced composite occlusal veneers demonstrated more favorable outcomes in terms of marginal gap and fracture resistance at both tested thicknesses compared to virgilite-based lithium disilicate glass-ceramic. Additionally, caution should be exercised during the construction of occlusal veneers from virgilite-based lithium disilicate glass-ceramic with reduced thickness.


Assuntos
Envelhecimento , Força de Mordida , Humanos , Desenho Assistido por Computador , Resinas Epóxi , Estatísticas não Paramétricas
4.
Opt Express ; 32(2): 1218-1230, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297678

RESUMO

We report on an Yb:YAG thin-disk multipass amplifier delivering 100 ns long pulses at a central wavelength of 1030 nm with an energy of 330 mJ at a repetition rate of 100 Hz. The beam quality factor at the maximum energy was measured to be M2 < 1.17. The small signal gain is 21.7, and the gain at 330 mJ was measured to be 6.9. The 20-pass amplifier is designed as a concatenation of stable resonator segments in which the beam is alternately Fourier transformed and relay-imaged back to the disk by a 4f-imaging optical scheme stage. The Fourier transform propagation makes the output beam robust against spherical phase front distortions, while the 4f-stage is used to compensate the thermal lens of the thin-disk and to reduce the footprint of the amplifier.

5.
Front Psychol ; 15: 1326181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38420179

RESUMO

The hospitality industry is well-known for its challenging and high-pressure work settings. In this context, employees commonly face a multitude of stressors originating from their roles and job responsibilities, which can significantly impact their psychological wellbeing. Hence, based on the job demands-resources (JD-R) model and the spillover theory, this study aims to empirically explore the direct and indirect effect of work stress (assessed by role overload, ambiguity, and conflict) on psychological distress among frontline employees in 3- and 4-star Egyptian resorts while considering the mediating influence of work-family conflict (WFC). Four hypotheses were put to the test through the application of the PLS-SEM 4.0 version (4.0.9.9). Based on the findings from 563 frontline employees who participated in this research, the study supports the four hypotheses affirming that work-related stressors significantly contributed to employees' psychological distress. Further, the findings highlighted that these stressors significantly spill over into employees' family lives, generating conflicts between work and family roles. In addition, the results emphasized the significance of WFC as a contributing factor to employees' psychological distress. Finally, the study concluded that WFC partially mediates the link between work stress and employees' psychological distress. Based on these findings, some theoretical and practical implications for hospitality scholars, resort management, and policymakers were suggested to enhance the employees' wellbeing and mitigate psychological distress in this vital sector.

7.
Environ Sci Pollut Res Int ; 31(10): 15302-15320, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38294653

RESUMO

This research observes the impact of environmental corporate social responsibility (CSR) and green supply chain management (GSCM) on green competitive advantage in Chinese manufacturing SMEs. Top management commitment is used as a mediator between environmental CSR, GSCM, and green competitive advantage. Moreover, a pro-environmental business strategy is used as a moderator between top management commitment and green competitive advantage. A simple random sampling technique was used, and 331 questionnaires were part of the final analysis. PLS-SEM is used for hypothesis testing. The results reveal that environmental CSR does not influence green competitive advantage. GSCM, top management commitment, and pro-environmental business strategy significantly measure green competitive advantage. Top management commitment significantly mediates between environmental CSR, GSCM, and green competitive advantage. Finally, a pro-environmental business strategy significantly moderates between top management commitment and green competitive advantage. This study strives to provide insightful information for strategic managers of Chinese manufacturing SMEs to optimize green competitive advantage, including environmental CSR, GSCM, top management commitment, and pro-environmental business strategy in decision-making. This study adds value to the body of knowledge by concentrating on factors that determine green competitive advantage. This initial research integrates environmental CSR, GSCM, top management commitment, pro-environmental business strategy, and green competitive advantage in a single framework using natural resource-based view (RBV). Furthermore, the study would present various implications for managers and lines for future directions.


Assuntos
Comércio , Recursos Naturais , Projetos de Pesquisa
8.
Eur J Dent ; 18(1): 182-195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37059444

RESUMO

OBJECTIVE: The aim of this study was to evaluate the efficiency of slab shear bond strength test (Slab_SBS) versus the microtensile in evaluation of the bond strength of different substrates. MATERIALS AND METHODS: Forty-eight extracted caries-free human third molars were utilized for teeth specimens' preparation. After flattening of all molars' occlusal table, the specimens were divided into two groups based on the type of utilized restorative material: nanohybrid resin composite and resin-modified glass ionomer (RMGI). Each group was further subdivided into three subgroups according to the subsequently applied bond strength test and specimen width; microtensile bond strength test (µTBS), Slab_SBS [2 mm] and Slab_SBS [3 mm]. Both testing methods were additionally applied on CAD/CAM specimens, nanohybrid resin composite blocks (composite-to-composite), and ceramic blocks (ceramic-to-ceramic). CAD/CAM specimens were prepared and cemented and then sectioned and subdivided as followed for teeth specimens' preparation. Pretest failures (PTF), bond strength, and failure mode of each specimen were recorded. Representative three-dimensional (3D) finite element analysis (FEA) models were developed to simulate µTBS and Slab_SBS specimens. Data were statistically analyzed using Shapiro-Wilk test and Weibull analysis. RESULTS: Pretest failures were only noted in the µTBS subgroups. Slab_SBS provided comparable bond strength to the µTBS of all substrates with adhesive mode of failure. CONCLUSION: Slab_SBS is easier to prepare with consistent and predictable outcome with no pretest failures during specimen preparation and better stress distribution.

9.
Cells ; 12(22)2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37998379

RESUMO

Eight wheat cultivars, Sakha-94, Giza-171, Sids-1, Sids-12, Sids-13, Shandweel-1, Misr-1, and Misr-2, were evaluated for leaf rust at the seedling and adult stages in the 2021 and 2022 seasons. Biochemical, histological, and genetic analyses were performed to determine the link between cultivars that were either sensitive or resistant to the disease. Misr-2 and Giza-171 cultivars had the highest levels of resistance to leaf rust races in 2021 (LTCGT, STSJT, and TTTST) and 2022 (MBGJT, TTTKS, and TTTTT) at the seedling stage. However, at the adult stage, Sakha-94, Giza-171, Misr-1, and Misr-2 cultivars had the highest levels of resistance; consequently, they had the lowest final disease severity and the lowest values of AUDPC. The correlation between the seedling reaction and adult reaction was non-significant, with values of 0.4401 and 0.4793 in the 2021 and 2022 seasons, respectively. Throughout the biochemical, histological, and genetic analyses, it was observed that catalase, peroxidase, and polyphenol oxidase activities significantly increased in the resistant cultivars. The discoloration of superoxide (O2-) and hydrogen peroxide (H2O2) significantly decreased in resistant and moderately resistant wheat cultivars (Sakha-94, Giza-171, Misr-1, and Misr-2); higher hydrogen peroxide (H2O2) and superoxide (O2-) levels were recorded for the susceptible cultivars compared to the resistant cultivars. Molecular markers proved that the Lr50 gene was detected in the resistant cultivars. Puccinia triticina infections negatively affected most histological characteristics of flag leaves, especially in susceptible cultivars. The thickness of the blade (µ), the thickness of the upper and lower epidermis (UE and LE), the thickness of mesophyll tissue (MT), and bundle length and width in the midrib were decreased in susceptible cultivars such as Sids-1, Sids-13, and Shandwel-1 compared with resistant cultivars.


Assuntos
Basidiomycota , Triticum , Triticum/genética , Triticum/microbiologia , Antioxidantes , Peróxido de Hidrogênio , Superóxidos , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
10.
BMC Oral Health ; 23(1): 907, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993834

RESUMO

PURPOSE: To evaluate the effect of zirconia priming with MDP-Salt before MDP containing primers and self-adhesive cement on the shear bond strength. MATERIALS AND METHODS: Fully sintered high translucent zirconia specimens (n = 120) were assigned into 2 groups (n = 60 each): Control (No Pretreatment) and Methacryloyloxydecyl dihydrogen phosphate salt (MDP-Salt) pretreated. Each group was divided into 3 subgroups (n = 20) according to cementation protocol: 1) MDP + Silane primer and conventional resin cement, 2) MDP+ Bisphenyl dimethacrylate (BPDM) primer and conventional resin cement, and 3) MDP containing self-adhesive resin cement. Shear bond strength (SBS) was measured after 10,000 thermocycling. Contact angle was measured for tested groups. Surface topography was assessed using a 3D confocal laser scanning microscope (CLSM). Weibull analysis was performed for SBS and one-way ANOVA for contact angle and surface topography measurements (α = 0.05). RESULTS: The use of MDP-Salt significantly improved the SBS (p < .05) for all tested subgroups. Self-adhesive cement showed an insignificant difference with MDP + Silane group for both groups (p > .05). MDP + BPDM showed a significantly lower characteristic strength compared to self-adhesive resin cement when both were pretreated with MDP-Salt. No difference between all tested groups in the surface topographic measurements while MDP-Salt showed the highest contact angle. CONCLUSION: MDP-Salt pretreatment can improve bonding performance between zirconia and MDP containing products.


Assuntos
Colagem Dentária , Cimentos de Resina , Humanos , Cimentos de Resina/química , Cimentação , Cimentos Dentários , Sais , Silanos/química , Metacrilatos , Resistência ao Cisalhamento , Teste de Materiais , Propriedades de Superfície , Análise do Estresse Dentário
11.
Sci Rep ; 13(1): 19127, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37926736

RESUMO

In fact, bonding of zirconia restorations is still a big challenge in clinical situations and many bonding protocols discussed in literature might be still controversial. The aim of this was to study assess the bond strength of zirconia after alumina and glass-bead pre-treatments with two different primers in combination with conventional resin cement and 10-methacryloyloxydecyl dihydrogen phosphate (MDP) containing self-adhesive resin cement without priming. Fully sintered high translucent zirconia samples (n = 160) were assigned into 2 groups of pre-treatments (n = 80): Alumina-sandblasting (AB) and Glass-bead (GB). Then, each group was divided into 4 sub-groups according to priming and cement used (n = 20 each): conventional self-adhesive resin cement, MDP-silane Primer, MDP primer both with conventional self-adhesive resin cement, and MDP contained cement. Shear bond strength (SBS) was measured after thermocycling. Failure mode was analyzed using stereomicroscope. Contact angle and surface topography were investigated using other fully sintered samples (n = 30) constructed for that sole purpose, divided into control (no pre-treatment [unmodified], alumina-, and glass-bead sandblasted groups). Two-way ANOVA was performed for SBS and failure mode was analyzed. The use of Alumina-sandblasting showed higher SBS compared to Glass-bead pre-treatment for MDP-silane primer (p = 0.034) and MDP primer (p < 0.001). While MDP contained cement showed higher but insignificant SBS when pre-treated with glass-beads. Alumina-sandblasting and glass-bead pre-treatments improve bond strength of zirconia combined using primers before cementation with conventional resin cement. Also, self-adhesive MDP contained cement along with surface pre-treatment showed the highest achievable bond strength. It was concluded that both alumina-sandblasting and glass-bead blasting improved SBS combined with MDP containing self-adhesive resin cement reducing the required clinical steps during cementation of zirconia restorations.

12.
BMC Oral Health ; 23(1): 733, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37814251

RESUMO

BACKGROUND: To investigate the effect of silver diamine fluoride (SDF) application and activation on the bond strength of gutta-percha to dentin and resin bonded post to dentin. METHODS: Thirty-six human premolar teeth were used. The coronal part tooth was removed, and endodontic mechanical preparation was performed for all the teeth. The teeth were divided according to final rinse protocol (n = 9) as follows: Control group; no SDF application, SDF/NA; 38% SDF as a final rinse with no activation, SDF/MDA; 38% SDF as a final rinse with manual dynamic activation and SDF/US; 38% SDF as a final rinse with ultrasonic activation. Root canal obturation using lateral condensation technique followed by fiber post insertion after 48 h in the root canal after corresponding preparations. The roots were cut with a low-speed precision saw creating 2 mm thickness sections. A total of 4 sections were obtained from each tooth, 2 coronal specimens (with post) and 2 apical specimens (with Gutta percha). Each specimen was subjected to push-out bond strength test with a universal testing machine. Data were analyzed using two-way ANOVA. RESULTS: The Push-out bond strength at the apical root section was significantly higher in SDF/MDA and SDF/US groups compared to control group. While for the coronal part, all SDF treated specimen showed reduced Push-out bond strength. CONCLUSION: SDF application as final rinse may reduce the bonding performance between fiber post and dentine. Activation with manual and ultrasonic methods improved the bond strength at the apical root section.


Assuntos
Colagem Dentária , Materiais Restauradores do Canal Radicular , Humanos , Dentina , Guta-Percha , Fluoretos Tópicos , Teste de Materiais , Materiais Restauradores do Canal Radicular/química , Cavidade Pulpar
13.
BMC Oral Health ; 23(1): 638, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670270

RESUMO

BACKGROUND: Current study aimed to evaluate the effect of different decontamination procedures on micro-shear bond strength (µSBS) of sound (SoD) and caries-affected dentin (CAD) of two universal adhesives after blood-saliva contamination. METHODS: One hundred and eighty bovine anterior teeth were prepared and allocated into the respective groups according to tested dentin substrates [SoD, CAD], universal adhesives [Clearfil Bond Universal Quick (UBQ), All-Bond-Universal (ABU)], adhesive contamination stage [none, contamination before and after adhesives light-curing], and according to decontamination procedures [no decontamination, water rinsing, adhesive rebond, Ethylenediaminetetraacetic acid (ETDA) and chlorhexidine (CHX) application]. Universal adhesives were applied according to manufacturer instructions in self-etch (SE) bonding mode. Four composite microrods were built for each tooth. Specimens were kept in distilled water for 24 hours at 37°C before testing µSBS. Four-way ANOVA and Tukey HSD tests were used for data analysis. RESULTS: A statistically significant difference between contamination stages of both universal adhesives at different decontamination procedures for SoD and CAD. Highest µSBS was recorded for UBQ control group at SoD, while the least was recorded for light-cured ABU upon water rinsing decontamination procedure of CAD. CONCLUSIONS: Proper cavity isolation is mandatory to avoid possible contamination which can dramatically affect µSBS. CHX is a potent cavity decontaminant that can restore different dentin substrates bond strength. EDTA presents a promising substitute. UBQ adhesive showed better bonding performance than ABU to both dentin substrates. Application of regular cavity decontamination approaches is highly advised in daily practice to avoid possible detrimental effect of accidental cavity contamination.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Humanos , Animais , Bovinos , Cavidade Pulpar , Clorexidina , Ácido Edético , Água , Dentina
14.
BMC Oral Health ; 23(1): 665, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710194

RESUMO

BACKGROUND: One of the most common causes of aesthetic failure and restoration replacement is the tooth restorations color mismatch specifically after aging. METHODS: One hundred and two participants with endodontically treated first molar were selected clinically. The patients were randomly splited into two groups and restored either with Cerasmart hybrid ceramic or Vita Enamic polymer infiltrated ceramic network (PICN) crowns and cemented using dual cure adhesive cement. The color difference (ΔE) values after cementation at 0 (Baseline), 6, and 12 months of use were obtained by quantification of L*, a*, and b* values with a digital spectrophotometer. Mann-Whitney test used to compare between tested groups at each time point and between (α = 0.05). RESULTS: At 6 months follow-up intervals, Vita Enamic group showed the highest significant ∆L* (p = 0.035) and ∆a* (p < 0.001) compared to Cerasmart group. ∆b* and ∆E showed no significant difference between both groups (p > 0.05). Furthermore, all color parameters of both groups showed statistically significant difference at 12 months follow-up intervals. After 12 months, Vita Enamic restorations presented higher color change compared to Cerasmart restorations with a (p-value of 0.0120). When comparing the total color difference ∆Et through-out the follow-up intervals of Vita Enamic & Cerasmart groups, there were insignificant difference (p = 0.263). CONCLUSION: Both hybrid materials demonstrated comparable color stability after 1 year of clinical service within clinical acceptance range. However, Cerasmart demonstrated a better colour stability after 1 year. TRIAL REGISTRATION: ClinicalTrials.gov (ID: NCT05501808) 15/8/ 2022- 'retrospectively registered'.


Assuntos
Envelhecimento , Cimentação , Humanos , Cerâmica , Assistência Odontológica , Cemento Dentário
15.
Clin Implant Dent Relat Res ; 25(6): 1207-1215, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37654160

RESUMO

INTRODUCTION: Although the combined use of chemical and electrochemical decontamination protocols can completely remove contaminants from the surfaces of one-time used healing abutments (HAs), their effectiveness in multiple-used HAs remains unknown. We aimed to investigate the effect of reused HAs frequency on the implant-HA contact surface area, micro-gap, microleakage, and surface topography following chemical and combined chemical and electrochemical decontamination protocols. METHODS: Ninety bone level titanium implants were assembled with 90 bone level HAs, in which 80 contaminated HA samples were collected from human participants. The retrieved HAs were randomly divided into two groups according to the cleaning protocol: ultrasonication with 5.25% NaOCl solution for 15 min and steam autoclaving (group I); ultrasonication with 5.25% NaOCl solution for 15 min, followed by electrochemical cleaning and steam autoclaving (group II). The control group (group III) comprised 10 new unused HAs. The cleaning protocol was applied after each insertion as follows: (a) single-use and cleaning, (b) double-use and double cleaning cycles, (c) triple-use and triple cleaning cycles, and (d) more than triple-use and more than triple cleaning cycles. The contact surface area and micro-gap were assessed with micro-computed tomography scanning technique, microleakage test using 2% methylene blue staining, surface morphology with scanning electron microscopy, and surface elemental composition with energy-dispersive X-ray spectroscopy analysis. RESULTS: Group Id exhibited the smallest contact surface area. The values of the micro-gap volumes and microleakage were significantly different (p < 0.001) in the descending order of Id > Ic > Ib > IId > Ia, IIa, and III. Morphological evaluation of Groups IIa, IIb, and IIc revealed that residual biological debris was optimally removed without altering their surface properties. CONCLUSIONS: Chemical and electrochemical decontamination protocols are more effective than NaOCl cleaning methods, particularly for multiple consecutive uses with better decontamination levels, which decreases micro-gap volume and microleakage without surface alterations. Although the use of combined decontamination protocols for the contact surface area at the implant-HA interface showed comparable results with the control, change in the contact surface area was observed following the NaOCl cleaning methods. Therefore, titanium HA reuse can be considered in multiple times, if they are cleaned and sterilized using combined chemical and electrochemical decontamination protocols.


Assuntos
Implantes Dentários , Vapor , Humanos , Descontaminação/métodos , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Titânio/química , Microtomografia por Raio-X
16.
Opt Express ; 31(18): 29558-29572, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710753

RESUMO

We demonstrate an injection-seeded thin-disk Yb:YAG laser at 1030 nm, stabilized by the Pound-Drever-Hall (PDH) method. We modified the PDH scheme to obtain an error signal free from Trojan locking points, which allowed robust re-locking of the laser and reliable long-term operation. The single-frequency pulses have 50 mJ energy (limited to avoid laser-induced damage) with a beam quality of M2 < 1.1 and an adjustable length of 55-110 ns. Heterodyne measurements confirmed a spectral linewidth of 3.7 MHz. The short pulse build-up time (850 ns) makes this laser suitable for laser spectroscopy of muonic hydrogen, pursued by the CREMA collaboration.

17.
Saudi Pharm J ; 31(8): 101699, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37538193

RESUMO

Anemia during pregnancy is a worldwide problem that affects females worldwide. There is not enough data on the magnitude of this health problem in Al-Madinah city in Saudi Arabia. This study aimed to assess the prevalence and associated factors related to anemia during pregnancy in Al-Madinah city. In addition, assessed the impact of counseling by clinical pharmacist on anemic pregnant females. 300 pregnant females were assessed for anemia based on their hemoglobin level in a descriptive cross-sectional study. Those females were further interviewed to identify associating factors related to presence of anemia during pregnancy. Anemic females were randomized to receive either counseling by the clinical pharmacist in addition to the standard of care (interventional group) or standard of care without counseling (control group). Our result showed that 44% of pregnant women were anemic upon recruitment. Pregnant females of low socioeconomic status, those during the first trimester, multipara females, and those who did not receive nutritional education during pregnancy showed significantly higher odds of developing anemia. Clinical pharmacist-led counseling program significantly improved adherence with iron regimen (p-value < 0.01) and significantly increased patients' hemoglobin level 30-days after the intervention (p-value < 0.001).

18.
BMC Womens Health ; 23(1): 398, 2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516864

RESUMO

OBJECTIVE: Myomectomy is the preferred surgical approach to manage uterine fibroids. However, uterine fibroids are highly vascular tumors and, consequently, extremely susceptible to problems from myomectomy-related hemorrhage. Hence, we aim to compare oxytocin efficacy and safety profile versus tranexamic acid (TA) with ethamsylate for reducing bleeding during myomectomy. METHODS: This randomized, double-blinded multicenter study was performed between 20th August 2020 and 20th October 2020 at El-Galaa Teaching Hospital, El Hussein University Hospital, Al-Azhar University Hospitals of Assiut, and Al-Azhar University Hospitals of Damietta. One hundred and eighty patients were enrolled and divided into three groups: group (1) received an injection of 30 IU of oxytocin in 500 ml of normal saline; group (2) received injections of 1 g of TA, 250 mg of Ethamsylate, and 110 ml of normal saline IV; and group (3) received an injection of 110 ml of normal saline IV just before surgical incision. RESULTS: In 180 premenopausal women, oxytocin and TA with ethamsylate had no significant value in lowering intraoperative blood loss compared with the placebo for abdominal myomectomy (666.25 ± 183.03, 630.72 ± 145.83, and 646.67 ± 168.92, respectively (P = 0.506)). Non-significant trends were observed for a reduction in operation time (P = 0.760), intra/postoperative blood transfusion (P = 0.624), hospital stay (P = 0.986), postoperative fever (P = 0.659), and wound infection (P = 1). CONCLUSION: Oxytocin and TA with ethamsylate had no significant value in lowering intraoperative blood loss compared with the placebo for abdominal myomectomy which opens a new question about the role of the use of the hemostatic drug during myomectomy especially in centers with limited resources and had higher rates. TRIAL REGISTRATION: The study was registered on Pan African Clinical Trials Registry with the following number: PACTR202008739887429 and was approved on 24/08/2020.


Assuntos
Etamsilato , Leiomioma , Ácido Tranexâmico , Miomectomia Uterina , Humanos , Feminino , Ácido Tranexâmico/uso terapêutico , Ocitocina/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Solução Salina , Leiomioma/cirurgia
19.
bioRxiv ; 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37333139

RESUMO

RNA binding proteins (RBPs) play crucial roles in regulating every stage of the mRNA life cycle and mediating non-coding RNA functions. Despite their importance, the specific roles of most RBPs remain unexplored because we do not know what specific RNAs most RBPs bind. Current methods, such as crosslinking and immunoprecipitation followed by sequencing (CLIP-seq), have expanded our knowledge of RBP-RNA interactions but are generally limited by their ability to map only one RBP at a time. To address this limitation, we developed SPIDR (Split and Pool Identification of RBP targets), a massively multiplexed method to simultaneously profile global RNA binding sites of dozens to hundreds of RBPs in a single experiment. SPIDR employs split-pool barcoding coupled with antibody-bead barcoding to increase the throughput of current CLIP methods by two orders of magnitude. SPIDR reliably identifies precise, single-nucleotide RNA binding sites for diverse classes of RBPs simultaneously. Using SPIDR, we explored changes in RBP binding upon mTOR inhibition and identified that 4EBP1 acts as a dynamic RBP that selectively binds to 5'-untranslated regions of specific translationally repressed mRNAs only upon mTOR inhibition. This observation provides a potential mechanism to explain the specificity of translational regulation controlled by mTOR signaling. SPIDR has the potential to revolutionize our understanding of RNA biology and both transcriptional and post-transcriptional gene regulation by enabling rapid, de novo discovery of RNA-protein interactions at an unprecedented scale.

20.
bioRxiv ; 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37333282

RESUMO

Messenger RNAs (mRNAs) interact with RNA-binding proteins (RBPs) in diverse ribonucleoprotein complexes (RNPs) during distinct life-cycle stages for their processing and maturation. While substantial attention has focused on understanding RNA regulation by assigning proteins, particularly RBPs, to specific RNA substrates, there has been considerably less exploration leveraging protein-protein interaction (PPI) methodologies to identify and study the role of proteins in mRNA life-cycle stages. To address this gap, we generated an RNA-aware RBP-centric PPI map across the mRNA life-cycle by immunopurification (IP-MS) of ~100 endogenous RBPs across the life-cycle in the presence or absence of RNase, augmented by size exclusion chromatography (SEC-MS). Aside from confirming 8,700 known and discovering 20,359 novel interactions between 1125 proteins, we determined that 73% of our IP interactions are regulated by the presence of RNA. Our PPI data enables us to link proteins to life-cycle stage functions, highlighting that nearly half of the proteins participate in at least two distinct stages. We show that one of the most highly interconnected proteins, ERH, engages in multiple RNA processes, including via interactions with nuclear speckles and the mRNA export machinery. We also demonstrate that the spliceosomal protein SNRNP200 participates in distinct stress granule-associated RNPs and occupies different RNA target regions in the cytoplasm during stress. Our comprehensive RBP-focused PPI network is a novel resource for identifying multi-stage RBPs and exploring RBP complexes in RNA maturation.

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