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1.
J Dent Educ ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627911

RESUMO

INTRODUCTION: Three-dimensional (3D)-printing technology can provide customizable simulations, but its effects on patient care quality have not been well studied. This study aimed to assess the impact of practicing with patient-specific 3D-printed teeth models on the quality of patients' dental preparations performed by students transitioning to clinical training. Accordingly, the quality of posterior crown preparations was evaluated by objectively analyzing digital scans and grades in two groups: the study group, which practiced beforehand with patient-specific 3D-printed teeth models, and the control group, which did not practice with these models. METHODS: All 78 fourth-year dental students who had just finished their fixed prosthodontics course at the simulation laboratory with training on phantom heads and without previous clinical experience in crown preparations were invited to participate in the study. Sixty-eight agreed to take part and were randomly divided into a study group that practiced crown preparations on 3D-printed models of their own patient's teeth and a control group that did not practice with 3D-printed models and started their clinical work straightforwardly after simulation training. Students completed validated perception questionnaires on self-confidence and clinical skills before and after the protocol, which were compared using a chi-squared test. Crown preparations performed on 3D-printed models and then on patients were digitally scanned and objectively graded by prepCheck software for critical parameters, such as undercuts, taper, and occlusion reduction. Non-parametric tests were used to compare preparations on 3D-printed models and on patients performed by the study group and those on patients made by the control group. RESULTS: Initially, both groups reported similar perceptions of self-confidence and clinical skills levels. The study group significantly improved both aspects after the protocol. Analysis of the scanned preparations demonstrated that the study group removed less tooth structure from actual patients than from the initial 3D-printed models. In contrast, the control group showed excess occlusal clearance in their patients compared to the study group. CONCLUSIONS: Practicing patient-specific 3D-printed teeth before performing procedures clinically appears to enhance preparation quality and minimize unnecessary tooth reduction in early clinical experiences.

2.
J Egypt Natl Canc Inst ; 36(1): 10, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556604

RESUMO

BACKGROUND: Colorectal cancer (CRC) ranks third in cancer incidence globally and is the second leading cause of cancer-related mortality. The nucleoside diphosphate kinase 1 (NME1) and netrin 1 receptor (DCC) genes have been associated with resistance against tumorigenesis and tumor metastasis. This study investigates the potential association between NME1 (rs34214448 G > T and rs2302254 C > T) and DCC (rs2229080 G > C and rs714 A > G) variants and susceptibility to colorectal cancer development. METHODS: Samples from 232 colorectal cancer patients and 232 healthy blood donors underwent analysis. Variants were identified using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methodology. Associations were assessed using odds ratios (OR), and the p values were adjusted with Bonferroni test. RESULTS: Individuals carrying the G/T and T/T genotypes for the NME1 rs34214448 variant exhibited a higher susceptibility for develop colorectal cancer (OR = 2.68, 95% CI: 1.76-4.09, P = 0.001 and OR = 2.47, 95% CI: 1.37-4.47, P = 0.001, respectively). These genotypes showed significant associations in patients over 50 years (OR = 2.87, 95% CI: 1.81-4.54, P = 0.001 and OR = 2.99, 95% CI: 1.54-5.79, P = 0.001 respectively) and with early Tumor-Nodule-Metastasis (TNM) stage (P = 0.001), and tumor location in the rectum (P = 0.001). Furthermore, the DCC rs2229080 variant revealed that carriers of the G/C genotype had an increased risk for develop colorectal cancer (OR = 2.00, 95% CI: 1.28-3.11, P = 0.002) and were associated with age over 50 years, sex, and advanced TNM stages (P = 0.001). CONCLUSIONS: These findings suggest that the NME1 rs34214448 and DCC rs2229080 variants play a significant role in colorectal cancer development.


Assuntos
Neoplasias Colorretais , Neoplasias Gástricas , Humanos , Pessoa de Meia-Idade , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Genótipo , Neoplasias Gástricas/genética , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Estudos de Casos e Controles , Receptor DCC/genética , Nucleosídeo NM23 Difosfato Quinases/genética
3.
Dent Mater ; 40(4): 619-628, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369403

RESUMO

OBJECTIVES: To evaluate the clinical performance of posterior restorations over wet and dry dentin with an etch-and-rinse adhesive after 36 months of clinical service. METHODS: Forty-five participants were recruited, each one had at least two posterior teeth that needed restoration. Ninety restorations were placed on Class I or Class II cavities. For the restoration protocol, a simplified etch-and-rinse adhesive (Adper Single Bond 2) was applied over wet (WD) or dry dentin (DD) and later restored with a bulk-fill composite (Filtek Bulk Fill) under rubber dam isolation. Each restoration was evaluated using the World Dental Federation (FDI) criteria after 6, 12, and 36 months of clinical service, regarding the following principal restoration characteristics: postoperative sensitivity, marginal discoloration, marginal adaptation, fracture of material and retention, and recurrence of caries. Kruskal Wallis analysis of variance rank (α = 0.05) and Kaplan-Meier survival analysis were used for statistical analysis. RESULTS: After 36 months of clinical evaluation, no significant difference between groups was observed in each FDI criterion (p > 0.05). Twenty restorations (WD=10, DD=10) showed minor marginal staining, and twenty-two restorations (WD=11, DD=11) presented small marginal adaptation defects (p > 0.05). Four restorations were lost (WD = 2, DD = 2) and the fracture rates (95% confidence interval) were 94.9% for each one, without significant difference between wet and dry dentin (p > 0.05). SIGNIFICANCE: The degree of dentin moisture does not seem to affect the clinical performance of a simplified etch-and-rinse adhesive in posterior restorations when the adhesive is applied vigorously over the dentine surface.


Assuntos
Cárie Dentária , Cimentos Dentários , Humanos , Adesivos Dentinários/química , Cimentos de Resina , Restauração Dentária Permanente/métodos , Resinas Compostas/química , Cárie Dentária/terapia , Dentina , Adaptação Marginal Dentária
4.
J Dent ; 142: 104823, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38145806

RESUMO

OBJECTIVE: To evaluate the effect of prolonged (P) polymerization time of a universal adhesive system applied in etch-and-rinse (ER) or self-etch (SE) strategies on the clinical performance of restorations in non-carious cervical lesions (NCCLs), after 36 months of clinical service. METHODS: A total of 140 restorations were randomly placed in 35 subjects according to the polymerization time groups: ER (10 s); ER-P (40 s); SE (10 s); and SE-P (40 s) at 1,200 mW/cm2. Composite resin was placed incrementally. The restorations were evaluated immediately and after 6, 12, 18, and 36 months using the FDI criteria. Data were analyzed using the Kaplan-Meier survival test for retention loss, and the Kruskal-Wallis' test for secondary outcomes (α = 0.05). RESULTS: After 36 months, 19 restorations were lost: ER 6, ER-P 2, SE 9, SE-P 2. The retention rates were 82.3% for ER; 94.1 % for ER-P; 73.5 % for SE; and 94.1 % for SE-P, with a significant difference between ER vs. ER-P and SE vs. SE-P, as well as ER vs. SE-P and ER-P vs. SE (p < 0.0001). Minor defects were observed in 18 restorations for the marginal staining criteria: ER 5, ER-P 2, SE 8, SE-P 3; and in 33 restorations for the marginal adaptation criteria: ER 11, ER-P 4, SE 12, and SE-P 6 (p > 0.05). No restorations showed recurrence of caries or postoperative sensitivity. CONCLUSIONS: A prolonged polymerization time of 40 s improves the clinical performance of the universal adhesive for both adhesive strategies evaluated, even after 36 months. CLINICAL SIGNIFICANCE: Prolonging the polymerization time of a universal adhesive from 10 to 40 s has been shown to improve its clinical performance when used in NCCLs.


Assuntos
Cimentos Dentários , Adesivos Dentinários , Humanos , Resinas Compostas/uso terapêutico , Adaptação Marginal Dentária , Falha de Restauração Dentária , Restauração Dentária Permanente , Adesivos Dentinários/uso terapêutico , Polimerização , Cimentos de Resina/uso terapêutico , Colo do Dente/patologia , Método Duplo-Cego
5.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528750

RESUMO

Objectives: To evaluate the effect of pressure on the skin of upper lip in decreasing pain perception during a local maxillary anesthetic injection. Material and Methods: A split-mouth crossover randomized clinical trial was designed. Seventy-one volunteer students (23.6±1.9 years old, 53.5% women) were selected. A group chosen at random had their left or right side of upper lip compressed by a wooden clothes peg as the compression instrument and 0.6 ml of lidocaine 2% with epinephrine 1:100,000 was administered at the buccal apex level of the lateral incisors tooth. Two weeks later anesthesia was administered on the opposite side of the lip according to the randomization recorded. The intensity of perceived pain level between the two injections using a 100 mm visual analog scale (VAS) and co-variable effect were compared (Wilcoxon test p < 0.05, RStudio). Results: The average of the perceived pain with and without upper lip compression was 27.6±14.5 mm (range 0-80 mm) and 36.33±17.9 mm (range 10-90 mm) respectively (p= 0.002). No significant differences were recorded according the covariance analysis with the sex (p = 0.55) and age (p = 0.89). Conclusion: The upper lip compression significantly reduces the perception of pain during a local maxillary anesthetic technique.

6.
Pharmaceutics ; 15(12)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38140074

RESUMO

Brain neurodegenerative diseases are central nervous system (CNS) affections typically common in older adults. A new therapeutic approach for them consists of providing specific drugs to the CNS through blood circulation; however, the Blood-Brain Barrier (BBB) prevents almost 100% of neurotherapeutics from reaching the brain. There are indications that Focused Ultrasound (FUS), temporarily placed in the BBB, can achieve a controlled increase in temperature at its focus, allowing temporary, localized, and reversible opening of this barrier, which facilitates the temporary delivery of specific drugs. This work presents a FUS-based protocol for the local, temporary, and reversible opening of the BBB in Wistar rats. The proposed protocol specifies certain power, treatment times, and duty cycle to controllably increase the temperature at the region of interest, i.e., the substantia nigra. Numerical simulations using commercial software based on the finite element method were carried out to determine the optimal size of the craniotomies for nearly full-acoustic transmission. Experiments in rats were performed with the parameters used during computational simulations to determine the adequate opening of the BBB. For this, craniotomies of different sizes were made at coordinates of the substantia nigra, and FUS was applied from the exterior. The opening of the BBB was evaluated using Evans Blue (EB) as an indicator of the crossing of the dye from the blood vessels to brain tissue. Numerical simulations demonstrated a major distance reached by the ultrasound focus with a bigger diameter. Experimental results show the local, temporary, and reversible opening of the BBB through a 10 mm diameter craniotomy, which effectively allowed placing the ultrasound focus over the substantia nigra, unlike a 6 mm diameter craniotomy in which there is a deviation of the focus through that window. Moreover, from these results, it was also determined that the disruption of the BBB was reversible, with an opening duration of 6 h after FUS application. The experimental work developed in this study resulted in a minimally invasive method for the temporary opening of the BBB.

7.
ACS Appl Mater Interfaces ; 15(48): 56587-56599, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37983009

RESUMO

Luminescent materials responsive to external stimuli have captivated great attention owing to their potential implementation in noninvasive photonic sensors. Luminescent metal-organic frameworks (LMOFs), a type of porous crystalline material, have emerged as one of the most promising candidates for these applications. Moreover, LMOFs constructed with organic linkers that undergo excited-state intramolecular proton-transfer (ESIPT) reactions are particularly relevant since changes in the surrounding environment induce modifications in their emission properties. Herein, an ESIPT-based LMOF, UiO-66-(OH)2, has been synthesized, spectroscopically and photodynamically characterized, and tested for detecting multiple external stimuli. First, the spectroscopic and photodynamic characterization of the organic linker (2,5-dihydroxyterephthalic acid (DHT)) and the UiO-66-(OH)2 MOF demonstrates that the emission properties are mainly governed by the enol → keto tautomerization, occurring in the organic linker via the ESIPT reaction. Afterward, the UiO-66-(OH)2 MOF proves for the first time to be a promising candidate to detect vapors of acid (HCl) and base (Et3N) toxic chemicals, changes in the mechanical compression (exercised pressure), and changes in the temperature. These results shed light on the potential of ESIPT-based LMOFs to be implemented in the development of advanced optical materials and luminescent sensors.

8.
Dent Mater ; 39(12): 1159-1168, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37839995

RESUMO

OBJECTIVES: The aim of this double-blind, and randomized controlled clinical trial was to evaluate the 5-year clinical performance of posterior resin composite restorations placed with the incremental filling technique [IF] or the bulk-fill technique [BF]. Two different adhesive systems were used: etch-&-rinse (ER) or self-etch (SE). METHODS: Posterior dental teeth of 72 participants (n = 236), with a cavity depth of at least 3 mm, were randomly divided into four groups. Restorations were applied with either Tetric N-Bond or Tetric N-Bond SE. The composite resin Tetric N-Ceram Bulk-Fill was placed either with IF or BF. Restorations were evaluated using FDI criteria at baseline and after 1, 2, 3, 4, and 5 years. Statistical analysis was performed using the Wilcoxon Signed rank test (a=0.05). RESULTS: Two hundred and four restorations were evaluated after 5 years. Eleven restorations were considered 'failed', ten due to fracture (4 IF and 6 BF) and one due to secondary caries (IF). The annual failure rate was 1.2% for BF and 1% for IF (p = 0.35). When comparing BF and IF, no significant differences were found for any of the parameters evaluated (p > 0.05). Regarding the adhesive systems, 44 and 51 restorations showed minor problems in terms of marginal adaptation and staining, with significantly more marginal discoloration when the self-etch adhesive was used (p = 0.002). SIGNIFICANCE: The bulk-fill restorative technique showed good clinical behavior compared to the incremental filling technique, especially when using an etch-&-rinse adhesive, after 5 years of clinical evaluation.


Assuntos
Cárie Dentária , Restauração Dentária Permanente , Humanos , Restauração Dentária Permanente/métodos , Resinas Compostas/química , Método Duplo-Cego , Cimentos de Resina , Adaptação Marginal Dentária
9.
Front Neurol ; 14: 1221160, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37669261

RESUMO

Introduction: Up to 80% of post-stroke patients present upper-limb motor impairment (ULMI), causing functional limitations in daily activities and loss of independence. UMLI is seldom fully recovered after stroke when using conventional therapeutic approaches. Functional Electrical Stimulation Therapy (FEST) controlled by Brain-Computer Interface (BCI) is an alternative that may induce neuroplastic changes, even in chronic post-stroke patients. The purpose of this work was to evaluate the effects of a P300-based BCI-controlled FEST intervention, for ULMI recovery of chronic post-stroke patients. Methods: A non-randomized pilot study was conducted, including 14 patients divided into 2 groups: BCI-FEST, and Conventional Therapy. Assessments of Upper limb functionality with Action Research Arm Test (ARAT), performance impairment with Fugl-Meyer assessment (FMA), Functional Independence Measure (FIM) and spasticity through Modified Ashworth Scale (MAS) were performed at baseline and after carrying out 20 therapy sessions, and the obtained scores compared using Chi square and Mann-Whitney U statistical tests (𝛼 = 0.05). Results: After training, we found statistically significant differences between groups for FMA (p = 0.012), ARAT (p < 0.001), and FIM (p = 0.025) scales. Discussion: It has been shown that FEST controlled by a P300-based BCI, may be more effective than conventional therapy to improve ULMI after stroke, regardless of chronicity. Conclusion: The results of the proposed BCI-FEST intervention are promising, even for the most chronic post-stroke patients often relegated from novel interventions, whose expected recovery with conventional therapy is very low. It is necessary to carry out a randomized controlled trial in the future with a larger sample of patients.

10.
ACS Appl Mater Interfaces ; 15(30): 36434-36446, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37477336

RESUMO

Mixed-metal-organic frameworks (MMOFs) have emerged as promising photocatalyst candidates in multiple reactions. For instance, the doping of Zr-UiO-type MOFs with Ce atoms increases their photoactivity owing to a better overlap between the organic linker and Ce orbitals. However, it is not clear which is the ideal content of Ce to reach the optimal photocatalytic performance. Herein, a series of MMOFs isostructural to UiO-66 and with napthalene-2,6-dicarboxylate (NDC) as a linker were synthesized and characterized. The Ce content was varied from 0 to 100% and their corresponding structural, chemical, photodynamic, and photoresponse properties were investigated. Powder X-ray diffraction shows that when the content of Ce is 12% onward, in addition to the UiO-type structure, a second crystalline structure is cosynthesized (NDC-Ce). Steady-state and femtosecond (fs) to millisecond (ms) spectroscopy studies reveal the existence of two competing processes: a linker excimer formation and an ultrafast ligand-to-cluster charge transfer (LCCT) phenomenon from the organic linker to Zr/Ce metal clusters. The ultrafast (fs-regime) LCCT process leads to the formation of long-lived charge-separated states, which are more efficiently photoproduced when the content of Ce reaches 9%, suggesting that the related material would show the highest photoactivity. Photoaction spectroscopic measurements corroborate that the sample with 9% of Ce exhibits the maximum photocatalytic efficiency, which is reflected in a 20% increment in overall water splitting efficiency compared with the monometallic Zr-based MOF. The current study demonstrates the relationship between the photodynamical properties of the MMOFs and their photocatalytic performance, providing new findings and opening new ways for improving the design of new MOFs with enhanced photocatalytic activities.

11.
Dent Mater ; 39(9): 820-830, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37481368

RESUMO

OBJECTIVES: This study aimed to evaluate the effect of copper nanoparticles (CuNp) on the clinical performance of a universal adhesive system used as an etch-and-rinse or self-etch strategy. METHODS: A total of 216 class V (non-carious lesions) restorations were randomly placed in 36 subjects according to the following groups: ERcu, adhesive in etch-and-rinse with 0.1% CuNp; ERct, adhesive in etch-and-rinse without CuNp; SEcu, adhesive in self-etch with 0.1% CuNp; and Sect, adhesive in self-etch without CuNp. Restorations were evaluated at baseline and at 6, 12, 18, 36, and 48 months, using the FDI and USPHS criteria. Appropriate statistical analyses were performed (α = 0.05). RESULTS: After 48 months, 14 restorations were lost (two for ERcu, five for SEcu, and seven for SEct) and the retention rates (95% confidence interval [CI]) were 74.1% for ERcu (95% CI 61.1-83.8); 81.5% for ERct (95% CI 69.2-89.6); 64.8% (95% CI 51.5-76.2) for SEcu; and 64.8% (95% CI 51.5-76.2) for SEct, with statistical differences between SEct vs. ERct and SEcu vs. ERct (p < 0.05). No significant differences between the groups were observed when the secondary parameters were evaluated (p > 0.05). Nineteen restorations (two for ERcu, two for ERct, six for SEcu, and nine for SEct) showed minor marginal staining, and 44 restorations (7 for ERcu, 8 for ERct, 14 for SEcu, and 15 for SEct) presented minimal marginal adaptation defects. SIGNIFICANCE: This is the first long-term clinical trial to show that the addition of CuNp to a universal adhesive system does not affect clinical performance.


Assuntos
Cárie Dentária , Nanopartículas , Estados Unidos , Humanos , Cobre , Projetos de Pesquisa , Coloração e Rotulagem
12.
Diagnostics (Basel) ; 13(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36766630

RESUMO

BACKGROUND: Gastrointestinal angiodysplasias (GIADs), also known as gastrointestinal angioectasias, are dilated, abnormally thin-walled blood vessels that occur in the mucosa and submucosa throughout the gastrointestinal tract. As a common cause of small bowel bleeding, GIADs have a significant impact on patient's morbidity and healthcare costs. Presently, somatostatin has been used widely to treat GIADs, but it is unclear if other therapies are as beneficial and cost-effective as somatostatin in managing GIADs. (2) Methods: A retrospective chart review was performed, which included subjects treated with Lanreotide, a somatostatin analog, and other therapies at the VA Loma Linda Healthcare System (VALLHCC) from January 2006 to December 2018. Patients who had symptomatic GIADs were detected by video capsule endoscopy (VCE), a device-assisted enteroscopy (DAE) or, in our case, push enteroscopy (PE) with an Endocuff. (3) Results: Three hundred twelve patients were diagnosed with GIADs. In this group of patients, 72 underwent ablation (endoscopic BICAP) with the addition of Lanreotide (SST), 63 underwent ablation therapy, eight were treated with SST only, 128 received iron replacement only, 25 received iron plus SST therapy, and 61 were observed with no therapy. Each group was followed via their hemoglobin (Hgb) level immediately thereafter, and Hgb levels were then obtained every 3 months for a 12-month period. After ablation therapy, 63 patients maintained stable Hgb levels over the course of the study, suggesting a significant therapeutic effect by controlling active bleeding. The 27 patients receiving ablation +SST therapy did not show improvements when compared to ablation only and the 128 patients who received iron therapy alone. (4) Conclusions: Importantly, 12 years of managing these patients has given us a cost- and time-sensitive strategy to maintain the patients' Hgb levels and avoid hospital admissions for acute bleeding. Iron treatment alone is effective compared to SST treatment in recovering from GIADs. Eliminating SST treatment from therapeutic intervention would save $89,100-445,550 per patient, depending on the number of doses for private care patients and $14,286-28,772 for VA patients, respectively. A suggested therapy would be to perform DAE on actively bleeding patients, ablate the lesions using a coagulation method, and place the patient on iron. If that fails, gastroenterologists should repeat VCE and perform either PE with Endocuff or balloon enteroscopy (all DAEs).

13.
ACS Appl Mater Interfaces ; 15(2): 3099-3111, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36608171

RESUMO

InP-based quantum dots (QDs) are an environment-friendly alternative to their heavy metal-ion-based counterparts. Herein we report a simple procedure for synthesizing blue emissive InP QDs using oleic acid and oleylamine as surface ligands, yielding ultrasmall QDs with average sizes of 1.74 and 1.81 nm, respectively. Consecutive thin coating with ZnS increased the size of these QDs to 4.11 and 4.15 nm, respectively, alongside a significant enhancement of their emission intensities centered at ∼410 nm and ∼430 nm, respectively. Pure phase synthesis of these deep-blue emissive QDs is confirmed by powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Armed with femtosecond to millisecond time-resolved spectroscopic techniques, we decipher the energy pathways, reflecting the effect of successive ZnS passivation on the charge carrier (electrons and holes) dynamics in the deep-blue emissive InP, InP/ZnS, and InP/ZnS/ZnS QDs. Successive coating of the InP QDs increases the intraband relaxation times from 200 to 700 fs and the lifetime of the hot electrons from 2 to 8 ps. The lifetime of the cold holes also increase from 1 to 4 ps, and remarkably, the Auger recombination escalates from 15 to 165 ps. The coating also drastically decreases the quenching by the molecular oxygen of the trapped charge carriers at the surfaces of the QDs. Our results provide clues to push further the emission of InP QDs into more energetically spectral regions and to increase the fluorescence quantum yield, targeting the construction of efficient UV-emissive light-emitting devices (LEDs).

14.
Cochrane Database Syst Rev ; 1: CD012648, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36705482

RESUMO

BACKGROUND: Presbyopia occurs when the lens of the eyes loses its elasticity leading to loss of accommodation. The lens may also progress to develop cataract, affecting visual acuity and contrast sensitivity. One option of care for individuals with presbyopia and cataract is the use of multifocal or extended depth of focus intraocular lens (IOL) after cataract surgery. Although trifocal and bifocal IOLs are designed to restore three and two focal points respectively, trifocal lens may be preferable because it restores near, intermediate, and far vision, and may also provide a greater range of useful vision and allow for greater spectacle independence in individuals with presbyopia. OBJECTIVES: To assess the effectiveness and safety of implantation with trifocal versus bifocal IOLs during cataract surgery among people with presbyopia. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2022, Issue 3); Ovid MEDLINE; Embase.com; PubMed; ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 31 March 2022.  SELECTION CRITERIA: We included randomized controlled trials that compared trifocal and bifocal IOLs among participants 30 years of age or older with presbyopia undergoing cataract surgery. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology and graded the certainty of the body of evidence according to the GRADE classification. MAIN RESULTS: We identified seven studies conducted in Europe and Turkey with a total of 331 participants. All included studies assessed visual acuity using a logarithm of the minimum angle of resolution (LogMAR chart). Of them, six (86%) studies assessed uncorrected distance visual acuity (the primary outcome of this review). Some studies also examined our secondary outcomes including uncorrected near, intermediate, and best-corrected distance visual acuity, as well as contrast sensitivity. Study characteristics All participants had bilateral cataracts with no pre-existing ocular pathologies or ocular surgery. Participants' mean age ranged from 55 to 74 years. Three studies reported on gender of participants, and they were mostly women. We assessed all of the included studies as being at unclear risk of bias for most domains. Two studies received financial support from manufacturers of lenses evaluated in this review, and at least one author of another study reported receiving payments for delivering lectures with lens manufacturers. Findings All studies compared trifocal versus bifocal IOL implantation on visual acuity outcomes measured on a LogMAR scale. At one year, trifocal IOL showed no evidence of effect on uncorrected distance visual acuity (mean difference (MD) 0.00, 95% confidence interval (CI) -0.04 to 0.04; I2 = 0%; 2 studies, 107 participants; low-certainty evidence) and uncorrected near visual acuity (MD 0.01, 95% CI -0.04 to 0.06; I2 = 0%; 2 studies, 107 participants; low-certainty evidence). Trifocal IOL implantation may improve uncorrected intermediate visual acuity at one year (MD -0.16, 95% CI -0.22 to -0.10; I2 = 0%; 2 studies, 107 participants; low-certainty evidence), but showed no evidence of effect on best-corrected distance visual acuity at one year (MD 0.00, 95% CI -0.03 to 0.04; I2 = 0%; 2 studies, 107 participants; low-certainty evidence). No study reported on contrast sensitivity or quality of life at one-year follow-up. Data from one study at three months suggest that contrast sensitivity did not differ between groups under photopic conditions, but may be worse in the trifocal group in one of the four frequencies under mesopic conditions (MD -0.19, 95% CI -0.33 to -0.05; 1 study; I2 = 0%, 25 participants; low-certainty evidence). One study examined vision-related quality of life using the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) at six months, and suggested no evidence of a difference between trifocal and bifocal IOLs (MD 1.41, 95% CI -1.78 to 4.60; 1 study, 40 participants; low-certainty evidence). Adverse events Adverse events reporting varied among studies. Of five studies reporting information on adverse events, two studies observed no intraoperative and postoperative complications or no posterior capsular opacification at six months. One study reported that glare and halos were similar to the preoperative measurements. One study reported that 4 (20%) and 10 (50%) participants had glare complaints at 6 months in trifocal and bifocal group, respectively (risk ratio 0.40, 95% CI 0.15 to 1.07; 40 participants). One study reported that four eyes (11.4%) in the bifocal group and three eyes (7.5%) in the trifocal group developed significant posterior capsular opacification requiring YAG capsulotomy at one year. The certainty of the evidence for adverse events was low. AUTHORS' CONCLUSIONS: We found low-certainty of evidence that compared with bifocal IOL, implantation of trifocal IOL may improve uncorrected intermediate visual acuity at one year. However, there was no evidence of a difference between trifocal and bifocal IOL for uncorrected distance visual acuity, uncorrected near visual acuity, and best-corrected visual acuity at one year. Future research should include the comparison of both trifocal IOL and specific bifocal IOLs that correct intermediate visual acuity to evaluate important outcomes such as contrast sensitivity, quality of life, and vision-related adverse effects.


Assuntos
Extração de Catarata , Lentes Intraoculares , Presbiopia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Opacificação da Cápsula , Presbiopia/cirurgia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Nanoscale ; 15(2): 657-666, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36515217

RESUMO

Localized surface plasmon resonance (LSPR)-induced hot-carrier transfer provides an attractive alternative for light-harvesting using the full solar spectrum. This defect-mediated hot-carrier transfer is identical at the plasmonic semiconductor/semiconductor interface and can overcome the low efficiency of plasmonic energy conversion, thus boosting the efficiency of IR-light towards energy conversion. Here, using femtosecond transient absorption (TA) measurements, we directly observe the ultrafast non-radiative carrier dynamics of LSPR-driven hot holes created in CuS nanocrystals (NCs) and CuS/CdS hetero nanocrystals (HNCs). We demonstrate that in the CuS NCs, the relaxation dynamics follows multiple relaxation pathways. Two trap states are populated by the LSPR-induced hot holes in times (100-500 fs) that efficiently compete with the conventional LSPR mechanism (250 fs). The trapped hot holes intrinsically relax in 20-40 ps and then decay in 80 ns and 700 ns. In the CuS/CdS HNCs, once the CuS trap states have been populated by the LSPR-generated hot holes, the holes get transferred through plasmon induced transit hole transfer (PITCT) mechanism in 200-300 ps to the CdS acceptor phase and relax in 1-8 and 40-50 µs. The LSPR-recovery shows a weak excitation wavelength and fluence dependence, while the dynamics of the trap states remains largely unaffected. The direct observation of formation and decay processes of trap states and hole transfer from trap states provides important insight into controlling the LSPR-induced relaxation of degenerate semiconductors.

17.
Materials (Basel) ; 15(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36234094

RESUMO

A facile and versatile process to produce lithium metasilicate (Li2SiO3) from non-conventional silicon sources (two different sand sources from the central area of México) was developed. The synthesis protocol based on a solid-state reaction followed by a hydrothermal treatment resulted in highly pure lithium metasilicate, as corroborated by XRD, SEM-EDS, and XPS analysis. Furthermore, lithium metasilicate was used as a heterogeneous catalyst for biodiesel production from soybean oil, where conversion yields were compared according to the silicon source used (based on chemical purity, stability, and yield efficiency). The best performing metasilicate material displayed a maximum of 95.5% of biodiesel conversion under the following conditions: 180 min, 60 °C, 5% catalyst (wt./wt., catalyst-to-oil), and 18:1 (methanol:oil). This contribution opens up alternatives for the production of lithium metasilicate using non-conventional precursors and its use as an alternative catalyst in biodiesel production, displaying better chemical stability against humidity than conventional heterogeneous catalysts.

18.
ACS Appl Mater Interfaces ; 14(37): 42656-42670, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36067454

RESUMO

Luminescent metal-organic frameworks (LMOFs) are one of the most promising materials for being implemented as active layers in the fabrication of photonic devices such as luminescent sensors of harmful chemicals. It is highly desirable that these materials undergo quantifiable spectroscopic (absorption or emission) changes in the presence of vapors of those analytes, as in many industrial processes, these toxic compounds are in the gas phase. Although great progresses have been achieved in the field, in most of the examples reported hitherto, the detection of chemicals by LMOFs is attained in solution. Herein, we present a novel approach consisting of the encapsulation of proton transfer dyes (8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt, HPTS, and 3-hydroxyflavone, 3-HF) within the pores of two distinct MOFs. The trapped proton transfer dyes (PT-dyes) may exist as different structures (enol, anion, or zwitterion), each of these exhibiting unique optical properties. Indeed, our findings reveal that the dyes can be encapsulated as anionic or enol species. Remarkably, the PT-dye@MOF composites exhibit a high luminescence quantum yield (up to 30%), which is sensitive (showing shifting in the emission wavelengths with a concomitant quenching/enhancement of the intensity) in the presence of vapors of an acid (HCl) and a base (triethylamine). These results open a novel avenue for the development of smarter vapoluminescent MOF-based materials.

19.
Brain Sci ; 12(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36138954

RESUMO

The technology for transcranial magnetic stimulation (TMS) has significantly changed over the years, with important improvements in the signal generators, the coils, the positioning systems, and the software for modeling, optimization, and therapy planning. In this systematic literature review (SLR), the evolution of each component of TMS technology is presented and analyzed to assess the limitations to overcome. This SLR was carried out following the PRISMA 2020 statement. Published articles of TMS were searched for in four databases (Web of Science, PubMed, Scopus, IEEE). Conference papers and other reviews were excluded. Records were filtered using terms about TMS technology with a semi-automatic software; articles that did not present new technology developments were excluded manually. After this screening, 101 records were included, with 19 articles proposing new stimulator designs (18.8%), 46 presenting or adapting coils (45.5%), 18 proposing systems for coil placement (17.8%), and 43 implementing algorithms for coil optimization (42.6%). The articles were blindly classified by the authors to reduce the risk of bias. However, our results could have been influenced by our research interests, which would affect conclusions for applications in psychiatric and neurological diseases. Our analysis indicates that more emphasis should be placed on optimizing the current technology with a special focus on the experimental validation of models. With this review, we expect to establish the base for future TMS technological developments.

20.
Chem Rev ; 122(11): 10438-10483, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35427119

RESUMO

This review gives an authoritative, critical, and accessible overview of an emergent class of fluorescent materials termed "LG@MOF", engineered from the nanoscale confinement of luminescent guests (LG) in a metal-organic framework (MOF) host, realizing a myriad of unconventional materials with fascinating photophysical and photochemical properties. We begin by summarizing the synthetic methodologies and design guidelines for representative LG@MOF systems, where the major types of fluorescent guest encompass organic dyes, metal ions, metal complexes, metal nanoclusters, quantum dots, and hybrid perovskites. Subsequently, we discuss the methods for characterizing the resultant guest-host structures, guest loading, photophysical properties, and review local-scale techniques recently employed to elucidate guest positions. A special emphasis is paid to the pros and cons of the various methods in the context of LG@MOF. In the following section, we provide a brief tutorial on the basic guest-host phenomena, focusing on the excited state events and nanoscale confinement effects underpinning the exceptional behavior of LG@MOF systems. The review finally culminates in the most striking applications of LG@MOF materials, particularly the "turn-on" type fluorochromic chemo- and mechano-sensors, noninvasive thermometry and optical pH sensors, electroluminescence, and innovative security devices. This review offers a comprehensive coverage of general interest to the multidisciplinary materials community to stimulate frontier research in the vibrant sector of light-emitting MOF composite systems.


Assuntos
Estruturas Metalorgânicas , Luminescência , Estruturas Metalorgânicas/química , Metais/química
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