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Gallium-based liquid metals (GaLMs) are promising for a variety of applications-especially as a component material for soft devices-due to their fluidic nature, low toxicity and reactivity, and high electrical and thermal conductivity comparable to solid counterparts. Understanding the interfacial properties and behaviors of GaLMs in different environments is crucial for most applications. When exposed to air or water, GaLMs form a gallium oxide layer with nanoscale thickness. This "oxide nano-skin" passivates the metal surface and allows for the formation of stable microstructures and films despite the high-surface tension of liquid metal. The oxide skin easily adheres to most smooth surfaces. While it enables effective printing and patterning of the GaLMs, it can also make the metals challenging to handle because it adheres to most surfaces. The oxide also affects the interfacial electrical resistance of the metals. Its formation, thickness, and composition can be chemically or electrochemically controlled, altering the physical, chemical, and electrical properties of the metal interface. Without the oxide, GaLMs wet metallic surfaces but do not wet non-metallic substrates such as polymers. The topography of the underlying surface further influences the wetting characteristics of the metals. This review outlines the interfacial attributes of GaLMs in air, water, and other environments and discusses relevant applications based on interfacial engineering. The effect of surface topography on the wetting behaviors of the GaLMs is also discussed. Finally, we suggest important research topics for a better understanding of the GaLMs interface.
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Photothermal therapy (PTT) holds great promise as a cancer treatment modality by generating localized heat at the tumor site. Among various photothermal agents, gallium-based liquid metal (LM) has been widely used as a new photothermal-inducible metallic compound due to its structural transformability. To overcome limitations of random aggregation and dissipation of administrated LM particles into a human body, we developed LM-containing injectable composite hydrogel platforms capable of achieving spatiotemporal PTT and chemotherapy. Eutectic gallium-indium LM particles were first stabilized with 1,2-Distearoyl-snglycero-3-phosphoethanolamine (DSPE) lipids. They were then incorporated into an interpenetrating hydrogel network composed of thiolated gelatin conjugated with 6-mercaptopurine (MP) chemodrug and poly(ethylene glycol)-diacrylate. The resulted composite hydrogel exhibited sufficient capability to induce MDA-MB-231 breast cancer cell death through a multi-step mechanism: (1) hyperthermic cancer cell death due to temperature elevation by near-infrared laser irradiation via LM particles, (2) leakage of glutathione (GSH) and cleavage of disulfide bonds due to destruction of cancer cells. As a consequence, additional chemotherapy was facilitated by GSH, leading to accelerated release of MP within the tumor microenvironment. The effectiveness of our composite hydrogel system was evaluated both in vitro and in vivo, demonstrating significant tumor suppression and killing. These results demonstrate the potential of this injectable composite hydrogel for spatiotemporal cancer treatment. In conclusion, integration of PTT and chemotherapy within our hydrogel platform offers enhanced therapeutic efficacy, suggesting promising prospects for future clinical applications. STATEMENT OF SIGNIFICANCE: Our research pioneers a breakthrough in cancer treatments by developing an injectable hydrogel platform incorporating liquid metal (LM) particle-mediated photothermal therapy and 6-mercaptopurine (MP)-based chemotherapy. The combination of gallium-based LM and MP achieves synergistic anticancer effects, and our injectable composite hydrogel acts as a localized reservoir for specific delivery of both therapeutic agents. This platform induces a multi-step anticancer mechanism, combining NIR-mediated hyperthermic tumor death and drug release triggered by released glutathione from damaged cancer populations. The synergistic efficacy validated in vitro and in vivo studies highlights significant tumor suppression. This injectable composite hydrogel with synergistic therapeutic efficacy holds immense promise for biomaterial-mediated spatiotemporal treatment of solid tumors, offering a potent targeted therapy for triple negative breast cancers.
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Neoplasias de la Mama , Galio , Hidrogeles , Hidrogeles/química , Galio/química , Galio/farmacología , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/terapia , Animales , Línea Celular Tumoral , Inyecciones , Fototerapia , Ratones Desnudos , Ratones , Terapia Fototérmica , Ratones Endogámicos BALB CRESUMEN
This study presents a transparent and ion-conductive hydrogel with suppressed water loss. The hydrogel comprises agarose polymer doped with sucrose and sodium chloride salt (NaCl-Suc/A hydrogel). Sucrose increases the water retention of the agarose gel, and the Na and Cl ions dissolved in the gel provide ionic conductivity. The NaCl-Suc/A gel shows high retention capability and maintains a 45% water uptake after 4 h of drying at 60 °C without encapsulation at the optimum gel composition. The doped NaCl-Suc/A hydrogel demonstrates improved mechanical properties and ionic conductivity of 1.6 × 10-2 (S/cm) compared to the pristine agarose hydrogel. The self-healing property of the gel restores the electrical continuity when reassembled after cutting. Finally, to demonstrate a potential application of the ion-conductive hydrogel, a transparent and flexible pressure sensor is fabricated using the NaCl-Suc/A hydrogel, and its performance is demonstrated. The results of this study could contribute to solving problems with hydrogel-based devices such as rapid dehydration and poor mechanical properties.
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Glycosylation is closely related to cellular metabolism and disease progression. In particular, glycan levels in cancer cells and tissues increase during cancer progression. This upregulation of glycosylation in cancer cells may provide a basis for the development of new biomarkers for the targeting and diagnosis of specific cancers. Here, they developed a detection technology for pancreatic cancer cell-derived small extracellular vesicles (PC-sEVs) based on lectin-glycan interactions. Lectins specific for sialic acids are conjugated to Janus nanoparticles to induce interactions with PC-sEVs in a dielectrophoretic (DEP) system. PC-sEVs are selectively bound to the lectin-conjugated Janus nanoparticles (lectin-JNPs) with an affinity comparable to that of conventionally used carbohydrate antigen 19-9 (CA19-9) antibodies. Furthermore, sEVs-bound Lectin-JNPs (sEVs-Lec-JNPs) are manipulated between two electrodes to which an AC signal is applied for DEP capture. In addition, the proposed DEP system can be used to trap the sEVs-Lec-JNP on the electrodes. Their results, which are confirmed by lectin-JNPs using the proposed DEP system followed by target gene analysis, provide a basis for the development of a new early diagnostic marker based on the glycan characteristics of PC-sEVs. In turn, these novel detection methods could overcome the shortcomings of commercially available pancreatic cancer detection techniques.
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Vesículas Extracelulares , Nanopartículas Multifuncionales , Neoplasias Pancreáticas , Humanos , Lectinas/metabolismo , Polisacáridos , Neoplasias Pancreáticas/diagnóstico , Vesículas Extracelulares/metabolismoRESUMEN
Pad-type thermal interface materials (TIMs) with composite structures are required to exhibit high thermal conductivity while maintaining conformal contact with the heat sink, which is strongly influenced by the type and content of the thermally conductive filler. This study presents that biphasic metal particles can be effectively aligned using the dielectrophoretic chaining (DEP-C) mechanism, thereby enhancing the thermal conductivity of a pad-type TIM. A eutectic gallium-indium (EGaIn) alloy liquid metal and solid copper were used as the filler materials with two different phases. The biphasic metal particle mixture of EGaIn and Cu (EGaIn-Cu) were better aligned by DEP-C than when they presented individually because fusion between the two particles increased the effective size. As expected, the thermal conductivity of the TIM composites increased when DEP-C aligned the filler. Notably, TIMs with both EGaIn-Cu fillers showed the largest increase in thermal conductivity, of up to 64.6%, and the highest thermal conductivity values after DEP-C application compared to TIMs with only the EGaIn or Cu filler. Finally, the heat dissipation performance of the TIM composite on a lit light-emitting diode is shown, where the TIM with DEP-C-aligned fillers exhibits improved performance.
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Recently, several methods have been used for cancer treatment. Among them, chemotherapy is generally used, but general anticancer drugs may affect normal cells and tissues, causing various side effects. To reduce the side effects and increase the efficacy of anticancer drugs, a folate-based liquid-metal drug nanodelivery system was used to target the folate receptor, which is highly expressed in cancer cells. A phospholipid-based surface coating was formed on the surface of liquid-metal nanoparticles to increase their stability, and doxorubicin was loaded as a drug delivery system. Folate on the lipid shell surface increased the efficiency of targeting cancer cells. The photothermal properties of liquid metal were confirmed by near-infrared (NIR) laser irradiation. After treating cancerous and normal cells with liquid-metal particles and NIR irradiation, the particles were specifically bound to cancer cells for drug uptake, confirming photothermal therapy as a drug delivery system that is expected to induce cancer cell death through comprehensive effects such as vascular embolization in addition to targeting cancer cells.
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OBJECTIVE: Prelacrimal recess approach can be used to access lesions of the anterior wall of the maxillary sinus (MS). Moreover, the longer the prelacrimal recess window distance (PLRWD), the easier it is to access the anterior wall. This study aimed to define the correlation between maxillary sinus pneumatization (MSP) and PLRWD, a previously defined anatomic factor predictive of the ease of prelacrimal recess approach (PLRA). METHODS: In total, 506 sides of 253 participants were studied. In the axial image, the PLRWD, the distance between the anterior wall of the MS and the lacrimal duct, was measured through radioanatomical analysis and classified as type I (<3 mm), type II (3-7 mm), or type III (>7 mm). On the coronal image, the distance between the nasal floor and the lower end of the MS was measured. When MSP did not reach the nasal floor, it was classified as grade I, as grade II when MSP reached the nasal floor, and grade III when the MS was pneumatized below the nasal floor. RESULTS: Type I included 115 sides (22.7%); type II, 277 sides (54.7%); and type III, 114 sides (22.5%). Grade I was observed in 58 sides (11.5%), grade II in 38 sides (7.5%), and grade III in 410 sides (81.0%). The mean PLRWD of grade I was 2.35 ± 2.41 mm, II was 3.37 ± 2.46 mm, and III was 5.55 ± 2.54 mm, showing a significant difference (P < .001). Post hoc analysis showed significant differences in the mean PLRWD among grades I, II, and III. Two anatomical factors, the MSP and PLRWD, were positively correlated (r = .507, P < .001). CONCLUSIONS: This study demonstrates a correlation between the feasibility of MSP and PLRA. Both MSP and PLRWD are essential diagnostic parameters for preoperative planning and better surgical outcomes.
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Five cranial nonmetric traits for sex estimation for sex estimation are classified by score according to geometry. The population of origin is one of the factors influencing cranial nonmetric traits. Moreover, among the five cranial traits, the robust traits for estimating sex varied across population. The aim of this study is to suggest the most useful method for sex estimation and demonstrate the need of a suitable method for each population. One-hundred thirty-five three-dimensional skull images from 21st century Korean autopsy cadavers were evaluated using the ordinal scoring system of five cranial nonmetric traits as outlined in Buikstra & Ubelaker (1994). All scores of each trait were analyzed by linear discriminant and decision tree analyses for sex estimation. The frequency of each trait was analyzed and compared to populations from other studies. The accuracy for both sexes was 88.1% by discriminant analysis and 90.4% by decision tree. The traits with the highest accuracy were the glabella and mastoid process in both discriminant analysis and decision tree. Sex estimation in modern Korean cadavers using the cranial nonmetric method was shown to be highly accurate by both discriminant analysis and decision tree. When comparing the pattern of frequency scores in this study with those of other populations, the pattern of trait scores for estimating sex was different for each population, even among populations in the same Asian region, which suggests the need for methods suited for specific populations.
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Pueblos del Este de Asia , Determinación del Sexo por el Esqueleto , Cráneo , Tomografía Computarizada por Rayos X , Femenino , Humanos , Masculino , Antropología Forense/clasificación , Antropología Forense/métodos , Hueso Frontal/anatomía & histología , Hueso Frontal/diagnóstico por imagen , Imagenología Tridimensional/métodos , Apófisis Mastoides/anatomía & histología , Apófisis Mastoides/diagnóstico por imagen , Determinación del Sexo por el Esqueleto/métodos , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Autopsia , CadáverRESUMEN
Recent advances in fabricating stretchable and transparent electrodes have led to various techniques for establishing next-generation form-factor optoelectronic devices. Wavy Ag nanowire networks with large curvature radii are promising platforms as stretchable and transparent electrodes due to their high electrical conductivity and stretchability even at very high transparency. However, there are disadvantages such as intrinsic nonregular conductivity, large surface roughness, and nanowire oxidation in air. Here, we introduce electrically synergistic but mechanically independent composite electrodes by sequentially introducing conducting polymers and ionic liquids into the wavy Ag nanowire network to maintain the superior performance of the stretchable transparent electrode while ensuring overall conductivity, lower roughness, and long-term stability. In particular, plenty of ionic liquids can be incorporated into the uniformly coated conducting polymer so that the elastic modulus can be significantly lowered and sliding can occur at the nanowire interface, thereby obtaining the high mechanical stretchability of the composite electrode. Finally, as a result of applying the composite film as the stretchable transparent electrode of stretchable organic solar cells, the organic solar cell exhibits a high power conversion efficiency of 11.3% and 89% compared to the initial efficiency even at 20% tensile strain, demonstrating excellent stretching stability.
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PURPOSE: Endoscopic sinus surgery has been widely used in the treatment of most maxillary diseases, although the inability to access lesions in the anterior and inferior maxillary sinus walls is a major disadvantage. In few cases, the prelacrimal recess (PLR) approach can be used, which secures an overall view within the maxillary sinus. The distance between the anterior maxillary wall and lacrimal duct is related to the ease of the PLR approach. First we measured the distance between the anterior maxillary wall and lacrimal duct using anatomical image analysis to classify the types and then evaluated whether anatomical factors were related to the results. METHODS: Both sides of the sinuses were evaluated in 272 participants (544 sides). After marking a tangent line (line 1 [L1]) through the posterior surface of the anterior maxillary sinus wall and a parallel line (line 2 [L2]) to the anterior surface of the lacrimal duct, the vertical distance between L1 and L2 was measured. Vertical distances of < 3 mm, 3-7 mm, and > 7 mm were classified as PLR approach types I, II, and III, respectively. In the axial plane image, line 3 (L3) (a horizontal line starting from the inner anterior maxillary sinus wall) was drawn and the angle with L1 (L1-L3A) was measured. RESULTS: The proportions of types I, II, and III were 23.2% (126), 55.0% (299), and 21.8% (119), respectively. The mean L1-L3As for types I, II, and III were 12.87 ± 4.92°, 11.20 ± 5.08°, and 10.40 ± 4.47°, respectively, showing a significant difference in mean values (p < 0.001). The L1-L3A and vertical distance between L1 and L2 showed a significant negative correlation (r = - 0.201, p < 0.001). CONCLUSIONS: We observed a correlation between the distance from the anterior maxillary wall to the lacrimal duct and L1-L3A. The L1-L3A indicates the degree of curvature of the anterior maxillary wall; therefore, the smaller the L1-L3A, the easier it may be to access the PLR.
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Asiático , Aparato Lagrimal , Humanos , Endoscopía , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugíaRESUMEN
BACKGROUND: Sphenoid sinus is a type of sinus surrounded by critical structures so that its injury potential to induce complications during surgery. The purpose of this study was to investigate the factors affecting the location of the sphenoid sinus natural ostium (SSO) to provide valuable data for endoscopic sinus surgery. METHODS: Ostiomeatal unit (OMU) computerized tomography (CT) was performed on 198 subjects. Across the left and right sides, 396 evaluation results were obtained. The vertical distance to determine the location of the SSO was analyzed based on Lines 1, 2 and 3 on the sagittal image. The horizontal distance was analyzed based on Lines 4 and 5 on the axial image. The upper, lower, medial and non-medial borders were defined according to the location of the SSO. The presellar, sellar and postsellar types were categorized according to the level of sphenoid sinus pneumatization (SSP) on the sagittal image. The presence and absence of Onodi cells were defined on the coronal image. Binary logistic regression analysis was performed to investigate each factor. RESULTS: As the rostrum width of the SSO on the horizontal position increased, the position toward non-medial boarder increased by 4.902 times so that the natural ostium showed a trend of lateralization. For the postsellar type, compared to the presellar type, the position toward the non-medial boarder decreased by 0.223 times, indicating that the postsellar type had the natural ostium showing a trend of medialization. In the presence of Onodi cells, the position toward the lower boarder increased by 2.599 times with a significant association. CONCLUSIONS: The results in this study indicated that the presellar type of SSP had the natural ostium exhibiting lateralization with an increase in the rostrum width, whereas the postsellar type had the natural ostium exhibiting medialization with a decrease in the rostrum width. Based on these findings, the methods to widen the natural ostium may be diversified.
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Senos Paranasales , Seno Esfenoidal , Humanos , Seno Esfenoidal/diagnóstico por imagen , Seno Esfenoidal/cirugía , Modelos Logísticos , Tomografía Computarizada por Rayos XRESUMEN
The hardness of poly (vinyl alcohol)-cryogels (PVA-CGs) was improved under three parameter conditions: 7.5 %-12.5 % PVA, 1-5 freezing-thawing cycles (FTCs), and the addition of 0 %-10 % glycerol as a cryoprotectant. This study investigated the effects of shear stress-induced destruction (SSID) on mechanical strength by inducing rapid erosion with a high frictional force. Tolerance to SSID (Tol-SSID) exhibited different sensitivities and trends depending on the above three fabrication parameters. The measured Tol-SSID exhibited consistent and inconsistent trends with tensile strength and swelling, respectively. Tol-SSID evaluation provides new insights into the practically meaningful mechanical strength of PVA-CGs against strong friction, which simulates extreme shear stress in a bioreactor. A PVA-CG with a PVA concentration of 10 % and in two FTCs resulted in Tol-SSID and tensile strength of 88.3 % and 0.59 kPa, respectively. Here, 5 % glycerol was added to maintain the bacterial respiration activity of immobilized nitrifiers of 0.097 mg-O2/g-VSS·min and survival of 88.6 %. The continuous mode of nitrification using the optimized PVA-CG for 10 days resulted in an ammonia removal rate of 0.2173 kg-N/m3·d, which is an improvement over cases without glycerol addition: 0.1426 and 0.1472 kg-N/m3·d for PVA-CGs in two and three FTCs, respectively.
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Criogeles , Alcohol Polivinílico , Alcohol Polivinílico/farmacología , Glicerol , Estrés Mecánico , Reactores BiológicosRESUMEN
Angiomatous polyps are an uncommon subtype of sinonasal polyps, characterized by extensive vascular proliferation and ectasia. The authors report the first case of angiomatous polyp originating from the inferior turbinate, which is a variant of the sinonasal polyp.
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Pólipos Nasales , Humanos , Pólipos Nasales/cirugía , Pólipos Nasales/patología , Cornetes Nasales/patologíaRESUMEN
This research describes a wearable skin hydration sensor based on cotton textile to determine the state of hydration within the skin via impedance analysis. The sensor structure comprises a textile substrate, thermoplastic over-layer, conductive patterns, and encapsulant, designed for stable and reliable monitoring of the skin's impedance change in relation to hydration level. The porcine skin with different hydration levels was prepared as a model system of the skin, and the textile-based sensor carefully investigated the porcine skin samples' impedance characteristics. The impedance study reveals that (1) the total impedance of skin decreases as its hydration level increases, and (2) the impedance of the stratum corneum and epidermis layers are more dominantly affected by the hydration level of the skin than the dermis layer. Even after repetitive bending cycles, the impedance data of skin measured by the sensor exhibit a reliable dependence on the skin hydration level, which validates the flexibility and durability of the sensor. Finally, it is shown that the textile-based skin hydration sensor can detect various body parts' different hydration levels of human skin while maintaining a stable conformal contact with the skin. The resulting data are well-matched with the readings from a commercial skin hydration sensor.
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Textiles , Dispositivos Electrónicos Vestibles , Impedancia Eléctrica , Humanos , PielRESUMEN
Herein, we present the imbibition-induced, spontaneous, and selective wetting characteristics of gallium-based liquid metal alloys on a metallized surface with micro-scale topographical features. Gallium-based liquid metal alloys are fascinating materials that have enormous surface tension; therefore, they are difficult to pattern into films. The complete wetting of eutectic alloy of gallium and indium is realized on microstructured copper surfaces in the presence of HCl vapor, which removes the native oxide from the liquid metal alloy. This wetting is numerically explained based on the Wenzel's model and imbibition process, revealing that the dimensions of the microstructures are critical for effective imbibition-driven wetting of the liquid metal. Further, we demonstrate that the spontaneous wetting of the liquid metal can be directed selectively along the microstructured region on the metallic surface to create patterns. This simple process enables the uniform coating and patterning of the liquid metal over large areas without an external force or complex processing. We demonstrate that the liquid metal-patterned substrates maintain electrical connection even in a stretched state and after repetitive stretching cycles.
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Gallium-based liquid metal (GaLM) alloys have been extensively used in applications ranging from electronics to drug delivery systems. To broaden the understanding and applications of GaLMs, this paper discusses the interfacial behavior of eutectic gallium-indium liquid metal (EGaIn) droplets in various solvents. No significant difference in contact angles of EGaIn is observed regardless of the solvent types. However, the presence or absence of a conical tip on EGaIn droplets after dispensing could indirectly support that the interfacial energy of EGaIn is relatively low in non-polar solvents. Furthermore, in the impact experiments, the EGaIn droplet bounces off in the polar solvents of water and dimethyl sulfoxide (DMSO), whereas it spreads and adheres to the substrate in the non-polar solvents of hexane and benzene. Based on the dimensionless We number, it can be stated that the different impact behavior depending on the solvent types is closely related to the interfacial energy of EGaIn in each solvent. Finally, the contact angles and shapes of EGaIn droplets in aqueous buffer solutions with different pH values (4, 7, and 10) are compared. In the pH 10 buffer solution, the EGaIn droplet forms a spherical shape without the conical tip, representing the high surface energy. This is associated with the dissolution of the "interfacial energy-reducing" surface layer on EGaIn, which is supported by the enhanced concentration of gallium ion released from EGaIn in the buffer solution.
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Elderly patients who underwent cataract surgery showed lower prevalence and cumulative incidence rates of hip and vertebral fragility fractures than those who did not. Therefore, cataract surgery in elderly patients may reduce the incidence of hip and vertebral fragility fractures. PURPOSE: The purpose of this study was to compare the incidence rates of hip and vertebral fragility fractures between patients who underwent cataract surgery and those who did not, and to investigate the effect of cataract surgery on the incidence of fragility fracture in elderly population using nationwide claims data. METHODS: A total of 558,147 participants from the National Health Insurance Service - Senior cohort were included. The participants were set into the hip fracture group (507,651) and vertebral fracture group (507,899) depending on the type of fracture. RESULTS: The number of hip fractures that occurred in the non-cataract surgery (NC) group was 36,971 (9.9%), while 8850 (6.6%) hip fractures occurred in the cataract surgery (C) group. The number of vertebral fractures that occurred in the NC group was 38,689 (10.3%), while 10,112 (7.6%) vertebral fractures occurred in the C group (all p < .001). The hazard ratios of hip and vertebral fractures were 0.58 and 0.60 for the total population that had undergone cataract surgery (all p < .001). The cumulative incidence rates of both fractures in the cataract surgery group were significantly lower than those in the non-cataract surgery group during 10 years (all p < .0001). CONCLUSION: Elderly patients who underwent cataract surgery showed a lower prevalence of hip and vertebral fragility fractures than those who did not. In addition, the cumulative incidence rates of both fractures in the cataract surgery group were lower than those in the non-cataract surgery group. Therefore, cataract surgery in elderly patients may reduce the incidence of hip and vertebral fragility fractures.
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Catarata , Fracturas de Cadera , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Anciano , Catarata/epidemiología , Estudios de Cohortes , Fracturas de Cadera/epidemiología , Fracturas de Cadera/cirugía , Humanos , Incidencia , Fracturas Osteoporóticas/epidemiología , Fracturas de la Columna Vertebral/epidemiologíaRESUMEN
This article presents a new method for understanding and visualizing convolutional neural networks (CNNs). Most existing approaches to this problem focus on a global score and evaluate the pixelwise contribution of inputs to the score. The analysis of CNNs for multilabeled outputs or regression has not yet been considered in the literature, despite their success on image classification tasks with well-defined global scores. To address this problem, we propose a new inverse-based approach that computes the inverse of a feedforward pass to identify activations of interest in lower layers. We developed a layerwise inverse procedure based on two observations: 1) inverse results should have consistent internal activations to the original forward pass and 2) a small amount of activation in inverse results is desirable for human interpretability. Experimental results show that the proposed method allows us to analyze CNNs for classification and regression in the same framework. We demonstrated that our method successfully finds attributions in the inputs for image classification with comparable performance to state-of-the-art methods. To visualize the tradeoff between various methods, we developed a novel plot that shows the tradeoff between the amount of activations and the rate of class reidentification. In the case of regression, our method showed that conventional CNNs for single image super-resolution overlook a portion of frequency bands that may result in performance degradation.
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Redes Neurales de la Computación , HumanosRESUMEN
Purpose: To identify the impact of hypertension (HTN) on macular microvasculature in type 2 diabetes (T2DM) patients without clinical diabetic retinopathy. Methods: In this retrospective cross-sectional study, subjects were divided into three groups: controls (control group), patients with T2DM (DM group), and patients with both T2DM and HTN (DM + HTN group). The vessel length density (VD) was compared among the groups. Linear regression analyses were performed to identify factors associated with VD. Results: The VD in the control, DM, and DM + HTN groups was 20.43 ± 1.16, 19.50 ± 1.45, and 18.19 ± 2.06 mm-1, respectively (P < 0.001). The best-corrected visual acuity (B = -9.30; P = 0.002), duration of T2DM (B = -0.04; P = 0.020), HTN (B = -0.51; P = 0.016), signal strength (B = 1.12; P < 0.001), and ganglion cell-inner plexiform layer thickness (B = 0.06; P < 0.001) were significant factors affecting VD in patients with T2DM. Additionally, the hemoglobin A1c (HbA1c) (B = -0.49; P = 0.016) was significantly associated with VD in patients with both T2DM and HTN. Conclusions: Patients with T2DM had impaired macular microvasculature, and patients with T2DM with HTN exhibited greater impairment of the microvasculature than did patients with T2DM only. Additionally, physicians should be aware that the macular microvasculature would be more vulnerable to hyperglycemic damage under ischemic conditions by HTN.
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Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/fisiopatología , Hipertensión/fisiopatología , Disco Óptico/irrigación sanguínea , Vasos Retinianos/fisiopatología , Anciano , Presión Sanguínea/fisiología , Estudios Transversales , Femenino , Angiografía con Fluoresceína , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Microvasos/fisiopatología , Persona de Mediana Edad , Células Ganglionares de la Retina/patología , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual/fisiologíaRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutations may diminish vaccine-induced protective immune responses, particularly as antibody titers wane over time. Here, we assess the effect of SARS-CoV-2 variants B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.429 (Epsilon), B.1.526 (Iota), and B.1.617.2 (Delta) on binding, neutralizing, and angiotensin-converting enzyme 2 (ACE2)competing antibodies elicited by the messenger RNA (mRNA) vaccine mRNA-1273 over 7 months. Cross-reactive neutralizing responses were rare after a single dose. At the peak of response to the second vaccine dose, all individuals had responses to all variants. Binding and functional antibodies against variants persisted in most subjects, albeit at low levels, for 6 months after the primary series of the mRNA-1273 vaccine. Across all assays, B.1.351 had the lowest antibody recognition. These data complement ongoing studies to inform the potential need for additional boost vaccinations.