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1.
Biol Reprod ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738783

RESUMEN

Cryptorchidism, the failure of one or both testes to descend into the scrotum, and testicular cancer show a strong correlation in both dogs and humans. Yet, long-standing medical debates persist about whether the location of undescended testes directly causes testicular cancer in humans or if both conditions stem from a common origin. Although testicular cancer is a prevalent disease in dogs, even less is known about its cause and correlation with testicular descent in this species. This review investigates the relation between these two disorders in dogs, drawing insights from human studies, and examines key biomarkers identified thus far. In addition, it explores potential causal links, including the impact of temperature on maturing testicular cells and a potential shared genetic origin. Notably, this literature review reveals significant differences between men and dogs in reproductive development, histological and molecular features of testicular tumors, and the prevalence of specific tumor types, such as Sertoli cell tumors (SCTs) in cryptorchid dogs and germ cell tumors (GCTs) in humans. These disparities caution against using dogs as models for human testicular cancer research and underscore the limitations when drawing comparisons between species. The paper concludes by suggesting specific research initiatives to enhance our understanding of the complex interplay between cryptorchidism and testicular cancer in dogs.

2.
J Prosthet Dent ; 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38443239

RESUMEN

Mandibular condyle fracture malunion and tooth loss can cause functional and esthetic problems. A patient with restricted mouth opening associated with muscle atrophy required prosthetic rehabilitation. Since the remaining teeth had a poor prognosis and the patient had difficulty adapting to the interim denture, complete mouth rehabilitation with implants was chosen. The implants were placed by using nerve lateralization and an autogenous bone graft. Prosthetic rehabilitation combines digital diagnosis and conventional prosthetic restorations. The definitive prosthesis was fabricated to ensure adequate oral hygiene and functional adaptation of the orofacial structures. Treatment resulted in stable masticatory function, occlusion, and esthetics and restored the function of the atrophied lips and restricted mouth opening.

3.
Int J Prosthodont ; 0(0): 1-17, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38373057

RESUMEN

PURPOSE: To determine whether food texture affects chewing side preference (CSP) and to investigate the relationship between CSP and masticatory factors such as occlusal contact area, bite force, and masticatory performance. MATERIALS AND METHODS: Forty-seven adults (20 women and 27 men; mean age, 24 years) participated in this study. Three types of food (chewing gum, beef jerky, and peanuts) were provided to assess CSP. Occlusal contact area was measured at various ranges of interocclusal distance, and the bite force was measured. Masticatory performance was assessed according to the median particle size. Asymmetry indices of each measurement were calculated and analyzed using Pearson's correlation coefficient (α = .05). RESULTS: The CSP for beef jerky and peanuts were significantly correlated with each other, whereas the CSP for chewing gum was not correlated with other food. The proportion of participants who chewed equally on both sides was higher for chewing gum than for beef jerky. There was a significant correlation between the CSP for beef jerky and occlusal contact area, especially at interocclusal distance ranges of 0-89 and 0-109 µm (r = 0.41). Bite force and masticatory performance were not significantly correlated with CSP. CONCLUSION: Food texture seemed to affect chewing side preference and masticatory laterality was greater for tough foods. Moreover, CSP for tough food was closely related to the occlusal contact area at about 0.1mm interocclusal distance level.

4.
Nanomicro Lett ; 16(1): 83, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38214803

RESUMEN

Composite solid electrolytes (CSEs) have emerged as promising candidates for safe and high-energy-density solid-state lithium metal batteries (SSLMBs). However, concurrently achieving exceptional ionic conductivity and interface compatibility between the electrolyte and electrode presents a significant challenge in the development of high-performance CSEs for SSLMBs. To overcome these challenges, we present a method involving the in-situ polymerization of a monomer within a self-supported porous Li6.4La3Zr1.4Ta0.6O12 (LLZT) to produce the CSE. The synergy of the continuous conductive LLZT network, well-organized polymer, and their interface can enhance the ionic conductivity of the CSE at room temperature. Furthermore, the in-situ polymerization process can also construct the integration and compatibility of the solid electrolyte-solid electrode interface. The synthesized CSE exhibited a high ionic conductivity of 1.117 mS cm-1, a significant lithium transference number of 0.627, and exhibited electrochemical stability up to 5.06 V vs. Li/Li+ at 30 °C. Moreover, the Li|CSE|LiNi0.8Co0.1Mn0.1O2 cell delivered a discharge capacity of 105.1 mAh g-1 after 400 cycles at 0.5 C and 30 °C, corresponding to a capacity retention of 61%. This methodology could be extended to a variety of ceramic, polymer electrolytes, or battery systems, thereby offering a viable strategy to improve the electrochemical properties of CSEs for high-energy-density SSLMBs.

6.
J Esthet Restor Dent ; 36(3): 445-452, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37671774

RESUMEN

OBJECTIVE: This in vitro study aimed to evaluate the flexural strength (FS) and translucency parameter (TP) of resin nanoceramics (RNCs) with barium silicate for additive manufacturing. MATERIALS AND METHODS: An RNC slurry was prepared by mixing a barium silicate filler and resin monomer. For the FS tests, specimens with three filler contents (0, 50, and 63 wt%) were designed according to ISO6872 for dental ceramics and ISO10477 for dental polymers. These specimens were then formed into discs with thicknesses of 1 and 2 mm for TP measurement. RESULTS: In the specimens prepared according to ISO6872, the FS increased significantly depending on the filler content. However, in the case of ISO10477, there was no significant difference between the FSs of the specimens with 0 and 50 wt% filler contents. The increase in thickness affected translucency, and the lowest translucency was obtained at a filler content of 63 wt%. The filler distribution was dense in the specimen with 63 wt% filler and uniform but relatively sparse in the specimen with 50 wt% filler. More voids were observed in the specimen with 63 wt% filler. The thickness and filler content of the specimen affected its TP. The TP of the specimen with 63 wt% filler was similar to that of human enamel. CONCLUSION: The FS was significantly higher at a filler content of 63 wt%. The lowest translucency was obtained at a filler content of 63 wt% for all tested thicknesses. CLINICAL SIGNIFICANCE: Increasing the filler content was advantageous for the mechanical properties of the RNCs. A high filler content led to low translucency in the RNCs. Therefore, the esthetics of human teeth can be reproduced if layering according to the filler content is performed in areas where esthetic characteristics are required.


Asunto(s)
Porcelana Dental , Resistencia Flexional , Humanos , Bario , Ensayo de Materiales , Silicatos , Propiedades de Superficie , Cerámica
7.
J Prosthodont ; 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38115183

RESUMEN

PURPOSE: The purpose of this in vitro study was to compare the tensile bond strength (TBS) of resin nanoceramics (RNC), zirconia, and lithium disilicate (LS2) restorations cemented to titanium abutments before and after thermomechanical aging. MATERIALS AND METHODS: Twelve specimens per group were fabricated to determine the TBS between a titanium abutment and four types of crown materials (2 RNCs, LS2, and translucent zirconia crowns for the maxillary molar). After milling, the abutments and crowns were cemented with resin cement after air-particle abrasion. In addition, thermomechanical aging (200,000 cycles, 50 N, 2 Hz) was applied to half of the specimens by using a mastication simulator. TBS was measured by using a universal testing machine. The interface between the crown and the cement was observed by using scanning electron microscopy (SEM). Two-way ANOVA was performed to analyze the effects of crown materials and thermomechanical aging. Failure-mode and interface analyses were also conducted. RESULTS: After thermomechanical aging, the TBS decreased in the LS2 specimens and increased in RNCs (p < 0.001). The ratio of mixed failure and debonding with the hole-sealing resin increased in the RNC group. SEM images showed the reduced gap between the crown and the resin cement after thermomechanical aging in the RNC group. CONCLUSIONS: Differences in TBS were affected by the crown materials after thermomechanical aging. After thermomechanical aging, the RNC crowns showed increased TBS, whereas LS2 and zirconia crowns exhibited decreased or similar TBS.

8.
J Environ Manage ; 345: 118833, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37639910

RESUMEN

In the present study, through the laboratory-to-field scale experiments and trials, we report the development and evaluation of an integrated oil-spill response system capable of oil collection, recovery (separation), and storage, for a timely and effective response to the initial stage of oil-spill accidents. With the laboratory-scale experiments, first, we evaluate that the water-surface waves tend to abate the oil recovery rate below 80% (it is above 95% for the optimized configuration without the waves), which is overcome by installing the hydrophilic (and oleophobic) porous structures at the inlet and/or near the water outlet of the separator. In the follow-up meso-scale towing tank tests with a scaled-up prototype, (i) we optimize the maneuverability of the assembled system depending on the speed and existence of waves, and (ii) evaluate the oil recovery performance (more than 80% recovery for the olive oil and Bunker A fuel oil). Although more thorough investigations and improvements are needed, a recovery rate of over 50% can be achieved for the newly enforced marine fuel oil (low sulfur fuel oil, LSFO) that was not targeted at the time of development. Finally, we perform a series of field tests with a full-scale system, to evaluate the rapid deployment and operational stability in the real marine environment. The overall floating balance and coordination of each functional part are sustained to be stable during the straight and rotary maneuvers up to the speed of 5 knots. Also, the collection of the floating debris (mimicking the spilled oil) is demonstrated in the field test. The present system is now being tested by the Korea Coast Guard and we believe that it will be very powerful to prevent the environmental damage due to the oil spills.


Asunto(s)
Aceites Combustibles , Contaminación por Petróleo , Bahías , Laboratorios , Agua
9.
Sci Rep ; 13(1): 9627, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316510

RESUMEN

Reproductive sterilization by surgical gonadectomy is strongly advocated to help manage animal populations, especially domesticated pets, and to prevent reproductive behaviors and diseases. This study explored the use of a single-injection method to induce sterility in female animals as an alternative to surgical ovariohysterectomy. The idea was based on our recent finding that repetitive daily injection of estrogen into neonatal rats disrupted hypothalamic expression of Kisspeptin (KISS1), the neuropeptide that triggers and regulates pulsatile secretion of GnRH. Neonatal female rats were dosed with estradiol benzoate (EB) either by daily injections for 11 days or by subcutaneous implantation of an EB-containing silicone capsule designed to release EB over 2-3 weeks. Rats treated by either method did not exhibit estrous cyclicity, were anovulatory, and became infertile. The EB-treated rats had fewer hypothalamic Kisspeptin neurons, but the GnRH-LH axis remained responsive to Kisspeptin stimulation. Because it would be desirable to use a biodegradable carrier that is also easier to handle, an injectable EB carrier was developed from PLGA microspheres to provide pharmacokinetics comparable to the EB-containing silicone capsule. A single neonatal injection of EB-microspheres at an equivalent dosage resulted in sterility in the female rat. In neonatal female Beagle dogs, implantation of an EB-containing silicone capsule also reduced ovarian follicle development and significantly inhibited KISS1 expression in the hypothalamus. None of the treatments produced any concerning health effects, other than infertility. Therefore, further development of this technology for sterilization in domestic female animals, such as dogs and cats is worthy of investigation.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Infertilidad , Femenino , Animales , Gatos , Perros , Ratas , Kisspeptinas/farmacología , Hipotálamo , Hormona Liberadora de Gonadotropina , Animales Domésticos , Esterilización , Estrógenos/farmacología
10.
Adv Sci (Weinh) ; 10(21): e2207744, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37199696

RESUMEN

Solid-state batteries (SSBs) are ideal candidates for next-generation high-energy-density batteries in the Battery of Things era. Unfortunately, SSB application is limited by their poor ionic conductivity and electrode-electrolyte interfacial compatibility. Herein, in situ composite solid electrolytes (CSEs) are fabricated by infusing vinyl ethylene carbonate monomer into a 3D ceramic framework to address these challenges. The unique and integrated structure of CSEs generates inorganic, polymer, and continuous inorganic-polymer interphase pathways that accelerate ion transportation, as revealed by solid-state nuclear magnetic resonance (SSNMR) analysis. In addition, the mechanism and activation energy of Li+ transportation are studied and visualized by performing density functional theory calculations. Furthermore, the monomer solution can penetrate and polymerize in situ to form an excellent ionic conductor network inside the cathode structure. This concept is successfully applied to both solid-state lithium and sodium batteries. The Li|CSE|LiNi0.8 Co0.1 Mn0.1 O2 cell fabricated herein delivers a specific discharge capacity of 118.8 mAh g-1 after 230 cycles at 0.5 C and 30 °C. Meanwhile, the Na|CSE|Na3 Mg0.05 V1.95 (PO4 )3 @C cell fabricated herein maintains its cycling stability over 3000 cycles at 2 C and 30 °C with zero-fading. The proposed integrated strategy provides a new perspective for designing fast ionic conductor electrolytes to boost high-energy solid-state batteries.

11.
Sci Rep ; 13(1): 2081, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36747044

RESUMEN

Enchondroma is the most common bone tumor in the hand. While standard surgical procedure is intra-lesional excision and bone grafting, there is a dispute between allogeneic bone, autogenous bone, and synthetic bone substitute grafting. Diverse adjuvant treatments have been introduced to reduce recurrence, but results are mixed with controversies. Meanwhile, whether existing descriptive classification could predict treatment outcome remains unclear. Thus, we reviewed patients with solitary enchondroma of the hand who underwent simple curettage followed by allogeneic cancellous bone chip impaction grafting. Eighty-eight patients with more than 5 years of follow-up were enrolled. Demographic data, local recurrence, and complications were reviewed. Duration of consolidation and the difference according to Takigawa classification were assessed. Range of motion (ROM), and functional scores were also evaluated. There were 51 women and 37 men, with a mean age of 37.9 years. Mean follow-up was 10.2 years. Recurrence occurred only in one patient. There was no complication. Mean postoperative total active motions of fingers and thumb were 239° and 132.9°. Mean modified Disabilities of the Arm, Shoulder, Hand score, and Musculoskeletal Tumor Society Score were 1.63, and 99.2 at the last follow-up. Consolidation, ROM, and functional scores according to Takigawa classification showed no significant differences. This study suggests that simple curettage with impaction grafting of allogeneic cancellous bone chip is a feasible method for treating solitary enchondromas involving short tubular bone of the hand with good long-term outcomes. Postoperative recurrence and complication rates were very low. Radiographic and clinical results were good regardless of the previous radiological classification.


Asunto(s)
Neoplasias Óseas , Condroma , Trasplante de Células Madre Hematopoyéticas , Masculino , Humanos , Femenino , Adulto , Hueso Esponjoso/patología , Mano/cirugía , Neoplasias Óseas/patología , Legrado , Condroma/cirugía , Condroma/patología , Estudios Retrospectivos , Estudios de Seguimiento
12.
Proc Natl Acad Sci U S A ; 120(2): e2211416120, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36595665

RESUMEN

Soft systems that respond to external stimuli, such as heat, magnetic field, and light, find applications in a range of fields including soft robotics, energy harvesting, and biomedicine. However, most of the existing systems exhibit nondirectional, nastic movement as they can neither grow nor sense the direction of stimuli. In this regard, artificial systems are outperformed by organisms capable of directional growth in response to the sense of stimuli or tropic growth. Inspired by tropic growth schemes of plant cells and fungal hyphae, here we report an artificial multistimuli-responsive tropic tip-growing system based on nonsolvent-induced phase separation of polymer solution, where polymer precipitates as its solvent dissolves into surrounding nonsolvent. We provide a theoretical framework to predict the size and velocity of growing precipitates and demonstrate its capability of sensing the directions of gravity, mechanical contact, and light and adjusting its growing direction in response. Exploiting the embedded physical intelligence of sensing and responding to external stimuli, our soft material system achieves multiple tasks including printing 3D structures in a confined space, bypassing mechanical obstacles, and shielded transport of liquids within water.


Asunto(s)
Células Vegetales , Polímeros , Gravitación
13.
J Prosthodont ; 32(9): 829-837, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36575827

RESUMEN

PURPOSE: The mechanical and physical properties of implant screw access opening deteriorate if composite resin is not polymerized properly. Therefore, this study aimed to analyze the effect of using composite resin in implant access opening on the degree of conversion (DC). MATERIALS AND METHODS: Two prosthetic materials (Co-Cr and zirconia), two types of composite resin (low and high viscosity), two light-cured resin depths (2 and 3 mm), and two polymerization methods (max-mode 10 s and mid-mode 20 s: 16 and 22 J/cm2 , respectively) were considered (n = 192). The DC of the polymerized composite resin was measured through Fourier-transform infrared spectroscopy. The top and bottom surfaces of the polymerized composite resin body were observed through scanning electron microscopy. Multiple linear regression analysis and analysis of variance were used to identify significant differences in DC (α = 0.05). RESULTS: The DC was lower when the low-viscosity composite resin (ß = -0.431), light-polymerized resin depth of 2 mm (ß = -0.430), zirconia prosthesis (ß = -0.191), and mid-mode polymerization method (ß = -0.164) were used. The resin type, depth of resin to be light-cured, prosthesis material, and polymerization method had an effect on the DC. CONCLUSIONS: Low-viscosity composite resin should be polymerized at a low irradiance and long polymerization time (such that the light-cured resin depth does not exceed 2 mm) to ensure proper composite resin polymerization in implant screw access opening.


Asunto(s)
Resinas Compuestas , Implantes Dentales , Resinas Compuestas/química , Polimerizacion , Ensayo de Materiales , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
14.
J Prosthet Dent ; 130(4): 620-628, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34980473

RESUMEN

STATEMENT OF PROBLEM: Lithium disilicate and 5 mol% yttria partially stabilized zirconia (5Y-PSZ) are commonly used for anterior restorations. However, studies comparing the durability of 5Y-PSZ and lithium disilicates are sparse. PURPOSE: The purpose of this in vitro study was to investigate the fracture load of anterior monolithic crowns made of 2 lithium disilicates and a 5Y-PSZ under dynamic loading. MATERIAL AND METHODS: Titanium abutments of the maxillary incisors were prepared (N=48, 8 for each group). Monolithic anterior crowns were made from the lithium disilicates (e.max CAD, Rosetta SM) and 5Y-PSZ (Katana UTML). After cementation, the specimens were stored in water for 24 hours and then thermocycled 10 000 times. Dynamic loading (70 N, 200 000 cycles, 1 Hz) was applied to half the specimens. The fracture load was measured by using a universal testing machine. The fracture patterns were analyzed and fractography applied. Two-way ANOVA and the Fisher exact test were used for statistical analysis (α=.05). RESULTS: The material and dynamic loading affected the fracture load of the anterior monolithic crowns (P<.05). However, there was no interaction between the material and the dynamic loading (P=.079). Both lithium disilicates had higher fracture loads than 5Y-PSZ (P<.05). The fracture load of each specimen was reduced after dynamic loading (P<.05). Lithium disilicate showed marginal and bulk fractures, and 5Y-PSZ presented catastrophic fractures (P<.001). CONCLUSIONS: 5Y-PSZ materials with large grains and low flexural strength may be less resistant to fractures under dynamic loading than lithium disilicates.

15.
J Adv Prosthodont ; 15(6): 302-314, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38205121

RESUMEN

PURPOSE: The aim of this study was to classify the shapes of retromolar pads and assess their morphometric differences using a 3D model. MATERIALS AND METHODS: Two hundred fully edentulous or Kennedy Class I partially edentulous patients (400 retromolar pads) were enrolled. Scan data of the definitive mandibular casts produced through functional impressions were obtained using a 3D laser scanner. Seven parameters (transverse diameter, longitudinal diameter, transverse-contour length, longitudinal-contour length, longitudinal/transverse diameter ratio, longitudinal/transverse-contour length ratio, and angle of the retromolar pad line to the residual alveolar ridge line) were measured using image analysis software. Subsequently, the pads were classified according to the shape. Statistical analyses were performed using 95% confidence intervals. RESULTS: Classifying the retromolar pads into three shapes led to high intra-examiner reliability (Cronbach's alpha = 0.933). The pear shape was the most common (56.5%), followed by oval/round (27.7%) and triangular (15.8%) shapes. There were no significant differences between the left and right sides according to the shape and no significant differences in any parameter according to age. The transverse diameter and longitudinal/transverse diameter ratio differed between sexes (P < .05). The triangular shape had a significantly different transverse diameter, transverse-contour length, longitudinal/transverse diameter ratio, and longitudinal/transverse-contour length ratio compared with the pear and oval/round shapes (P < .05). CONCLUSION: From a clinical reliability standpoint, classifying retromolar pads into three shapes (oval/round, pear-shaped, and triangular) is effective. The differences in the sizes among the shapes were attributed to the transverse measurement values.

16.
J Adv Prosthodont ; 14(5): 315-323, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36452363

RESUMEN

PURPOSE: The purpose of this study was to investigate the effect of barium silicate filler contents on mechanical properties of resin nanoceramics (RNCs) for additive manufacturing (AM). MATERIALS AND METHODS: Additively manufactured RNC specimens were divided into 4 groups depending on the content of ceramic fillers and polymers: 0% barium silicate and 100% polymer (B0/P10, control group); 50% barium silicate and 50% polymer (B5/P5); 60% barium silicate and 40% polymer (B6/P4); 67% barium silicate and 33% polymer (B6.7/P3.3). The compressive strength (n = 15) and fracture toughness (n = 12) of the specimens were measured, and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) analyses were performed. Independent sample Kruskal-Wallis tests were performed on the compressive strength and fracture toughness test results, and the significance of each group was analyzed at the 95% confidence interval through post-tests using the Bonferroni's method. RESULTS: B6/P4 and B6.7/P3.3 exhibited much higher yield strength than B0/P10 and B5/P5 (P < .05). Compared to the control group (B0/P10), the other three groups exhibited higher ultimate strength (P < .05). The fracture toughness of B6/P4 and B6.7/P3.3 were similar (P > .05). The content of barium silicate and fracture toughness showed a positive correlation coefficient (R = 0.582). SEM and EDS analyses revealed the presence of an oval-shaped ceramic aggregate in B6/P4 specimens, whereas the ceramic filler and polymer substrate were homogeneously mixed in B6.7/P3.3. CONCLUSION: Increasing the ceramic filler content improves the mechanical properties, but it can be accompanied by a decrease in the flowability and the homogeneity of the slurry.

17.
J Prosthet Dent ; 128(6): 1319.e1-1319.e10, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36334990

RESUMEN

STATEMENT OF PROBLEM: Studies that compared the fracture strength of monolithic lithium disilicate and 5-mol% yttria partially stabilized zirconia multiunit fixed dental prostheses are sparse. PURPOSE: As the connector is the weakest part of a fixed dental prosthesis, the purpose of this in vitro study was to investigate the effect of connector designs and material on the fracture strength of 3-unit monolithic fixed dental prostheses. MATERIAL AND METHODS: Resin-ceramic canine and premolar teeth (N=144) were prepared for fixed dental prosthesis abutments. Prostheses with 3 connector designs (width=height, widthheight) were made from 2 types of lithium disilicate (IPS e.max CAD and Amber Mill) and 5-mol% yttria partially stabilized zirconia (3M Lava Esthetic and Katana Zirconia UTML). Fracture strengths were measured after 200 000 cycles of dynamic loading of 50 N and thermocycling at 5 °C and 55 °C, and the fracture patterns were analyzed. Two-way analysis of variance and the Fisher exact test were used for statistical analysis (α=.05). RESULTS: The material and connector design affected the fracture strength of fixed dental prostheses (P<.05), and a significant interaction was found between the material and connector design (P<.05). The IPS e.max CAD material had significantly lower fracture strength than Amber Mill, 3M Lava Esthetic, or Katana Zirconia UTML (P<.05). Connector designs with a greater width versus height showed significantly lower fracture strengths than other designs (P<.05). CONCLUSIONS: The connector design of 3-unit fixed dental prostheses, particularly the connector height, may affect fracture strength depending on the prosthesis material.


Asunto(s)
Implantes Dentales , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Ámbar , Ensayo de Materiales , Estética Dental , Porcelana Dental , Circonio , Diseño Asistido por Computadora , Cerámica , Materiales Dentales
18.
J Orthop Surg (Hong Kong) ; 30(2): 10225536221113034, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35924635

RESUMEN

INTRODUCTION: Sarcopenia, a loss of muscle mass and strength with aging, is associated with various TKA-related complications. In 2020, the AWGS published an undated guideline (AWGS 2019) based on studies from East and Southeast Asia. The purpose of this study was to determine the prevalence of sarcopenia in Asian female patients awaiting primary total knee arthroplasty due to advanced knee osteoarthritis using the updated AWGS criteria. MATERIALS AND METHODS: The present study included 138 female patients who scheduled for primary TKA with severe osteoarthritis. The included patients were assessed with use of an AWGS 2019 diagnostic criteria based on muscle strength, physical performance, and appendicular skeletal muscle mass. Clinical parameters related to sarcopenia were collected and knee status assessed using the Knee Society scoring system. To better define the association with age, patients were stratified into following four groups: <60, 60-69, 70-79, ≥80. The prevalence of sarcopenia was identified, and the association between sarcopenia and clinical variables was analyzed. RESULTS: The prevalence of sarcopenia and severe sarcopenia in this cohort according to the updated AWGS criteria was 35.5% and 21.7%. Prevalence of sarcopenia and severe sarcopenia significantly increased with advancing age (p = .003, p = .040, respectively). Although not statistically significant, the proportion of severe sarcopenia among sarcopenia also increased with age. Multivariate logistic regression analysis revealed that lower BMI and lower 25-OH-vitamin D3 level were independent risk factors associated with sarcopenia in women awaiting TKA. CONCLUSIONS: In conclusion, our study confirmed that sarcopenia is more prominent amongst female patients awaiting primary TKA than the general population. Therefore, orthopedic surgeons should consider sarcopenia prevention and intervention in this group. Further studies are needed to investigate the effect of TKA on sarcopenia, and the difference of TKA outcomes between groups with or without underlying sarcopenia.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Sarcopenia , Artroplastia de Reemplazo de Rodilla/efectos adversos , Femenino , Fuerza de la Mano/fisiología , Humanos , Articulación de la Rodilla/cirugía , Fuerza Muscular , Prevalencia , Sarcopenia/diagnóstico , Sarcopenia/epidemiología
19.
Adv Sci (Weinh) ; 9(13): e2105448, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35240003

RESUMEN

In this study, tetraethylene glycol dimethyl ether (TEGDME) is demonstrated as an effective additive in poly(propylene carbonate) (PPC) polymers for the enhancement of ionic conductivity and interfacial stability and a tissue membrane is used as a backbone to maintain the mechanical strength of the solid polymer electrolytes (SPEs). TEGDME in the PPC allows the uniform distribution of conductive LiF species throughout the cathode electrolyte interface (CEI) layer which plays a critically important role in the formation of a stable and efficient CEI. In addition, the high modulus of SPEs suppresses the formation of a protrusion-type CEI on the cathode. The SPE with the optimized TEGDME content exhibits a high ionic conductivity of 0.89 mS cm-1 , an adequate potential stability of up to 4.89 V, and a high Li-ion transference number of 0.81 at 60 °C. Moreover, the Li/SPE/Li cell demonstrates excellent cycling stability for 1650 h, and the Li/SPE/LFP full cell exhibits an initial reversible capacity of 103 mAh g-1 and improved stability over 500 cycles at a rate of 1 C. The TEGDME additive improves the electrochemical properties of the SPEs and promotes the creation of a stable interface, which is crucial for ASSLIBs.


Asunto(s)
Suministros de Energía Eléctrica , Litio , Electrodos , Iones/química , Litio/química , Polímeros , Propano/análogos & derivados
20.
Clin Exp Reprod Med ; 49(1): 16-25, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35255655

RESUMEN

In mammalian species, females are born with a number of oocytes exceeding what they release via ovulation. In humans, an average girl is born with over a thousand times more oocytes than she will ovulate in her lifetime. The reason for having such an excessive number of oocytes in a neonatal female ovary is currently unknown. However, it is well established that the oocyte number decreases throughout the entire lifetime until the ovary loses them all. In this review, data published in the past 80 years were used to assess the current knowledge regarding the changing number of oocytes in humans and mice, as well as the reported factors that contribute to the decline of oocyte numbers. Briefly, a collective estimation indicates that an average girl is born with approximately 600,000 oocytes, which is 2,000 times more than the number of oocytes that she will ovulate in her lifetime. The oocyte number begins to decrease immediately after birth and is reduced to half of the initial number by puberty and almost zero by age 50 years. Multiple factors that are either intrinsic or extrinsic to the ovary contribute to the decline of the oocyte number. The inflammation caused by the ovulatory luteinizing hormone surge is discussed as a potential contributing factor to the decline of the oocyte pool during the reproductive lifespan.

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