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Although working men and women share common retirement concerns, women encounter unique challenges in securing their retirement. These challenges arise from factors such as part-time work, intermittent work histories, and potential wealth disparities. Marital status also exerts a profound influence on retirement decisions. Marital status significantly impacts their financial security as they approach retirement. This study investigates the intricate relationship between gender, marital status, and theory of planned behavior factors that influence retirement planning among older adults. Utilizing data from the 2014 Health and Retirement Study (HRS) and RAND, the research analyzed 2,657 participants aged 50 to 62, all of whom reported full or part-time employment. Also, the research leveraged the theory of planned behavior to examine motivational factors affecting retirement planning. The study's findings highlight the significant association of gender with expected retirement timing, revealing that married women typically anticipate retiring earlier than both unmarried women and men. In addition, older adults who secure retirement resources tend to retire earlier. It is important to develop tailored policies and initiatives to address the specific retirement challenges women face. It is imperative to develop retirement support systems that consider the gender, marital statuses, and retirement resources of older adults, and to give special attention to those who are vulnerable. This study provides valuable insights into the intricate interplay of gender, marital status, retirement motivation factors and retirement planning among older adults.
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PURPOSE: This study aimed to examine whether indirectly deterring elevator use through time-targeted Point-of-Decision Prompts (PODPs) efficiently increased stair usage in a university setting. METHODS: A quasi-experimental design (pre-post design) was employed over 2 weeks in September 2023. Baseline observations were conducted for 1 week prior to signage placement at two locations. The intervention in this study lasted for 1 week, immediately following baseline observations. Three hundred and thirty-one and 384 participants were observed during the baseline and intervention periods, respectively. Logistic regression analysis was used to examine the increase in the act of ascending the stairs. RESULTS: Our intervention, which focused on time-related messages, effectively increased stair usage among university students (coefficient = 0.435, p-value < 0.01). Furthermore, females (coefficient = -0.820, p-value < 0.05) and individuals aged ≥ 30 years (coefficient = 1.048, p-value < 0.01) were notably more likely to be influenced by our intervention than males and individuals aged < 30 years. CONCLUSION: Indirectly discouraging elevator use through time-targeted PODPs may amplify the effects of the previously employed time-related messages. Our findings suggested that a deterrence nudge should primarily be directed towards promoting stair usage among females or individuals aged ≥ 30 years.
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Promoción de la Salud , Subida de Escaleras , Estudiantes , Humanos , Masculino , Femenino , Universidades , Adulto , Promoción de la Salud/métodos , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Adulto Joven , Ascensores y Escaleras Mecánicas , AdolescenteRESUMEN
INTRODUCTION: Optic nerve sheath diameter (ONSD) reflects intracranial pressure and is increased in pre-eclampsia. Administrating a significant volume of epidural solution into the epidural space can potentially increase ONSD. We investigated the impact of epidural local anesthetic injection on ONSD in patients with pre-eclampsia. METHODS: Patients with pre-eclampsia (n=11) and normotensive pregnant women (n=11) received de novo epidural anesthesia for cesarean delivery. We administered 21 mL of an epidural solution containing 2% lidocaine and 50 µg fentanyl into the lumbar epidural space in incremental doses. ONSD was measured at baseline, 3, 10, and 20 min after completing the epidural injection, after delivery, and at the end of surgery. Primary outcome was the change in ONSD from baseline to 3 min after epidural injection in patients with pre-eclampsia and normotensive pregnant women. Serial changes in the ONSD were analyzed using a linear mixed model. RESULTS: At baseline and 3 min after epidural drug injection, ONSD was significantly larger in patients with pre-eclampsia than in normotensive mothers (5.7 vs 4.1 mm, p=0.001 and 5.4 vs 4.1 mm, p<0.001, respectively). However, there were no significant changes in ONSD at 3 min after injection from baseline in either group (p>0.999). Linear mixed model demonstrated that ONSD did not change after epidural anesthesia in either group (p=0.279 and p=0.347, respectively). CONCLUSIONS: Despite a higher baseline ONSD in pre-eclampsia, epidural anesthesia did not further increase ONSD. Our findings indicate that epidural anesthesia can be safely administered in patients with pre-eclampsia at risk of increased intracranial pressure, without other intracranial pathology. TRIAL REGISTRATION NUMBER: NCT04095832.
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With the increasing demand for highly efficient lighting in the automotive industry, flip-chip light-emitting diodes (LEDs) have become widely used for both interior and exterior lighting. Solder, serving as a crucial interconnecting material, often develops voids during the reflow process, compromising the integrity and reliability of the connections. Thus, understanding the impact of these voids on the mechanical and thermal properties of the product is vital for improving reliability accuracy. This work employs computational methods alongside experimental approaches to address the challenges of replicating solder voids and controlling the solder void fraction. A comprehensive study investigates the effects of solder voids on shearing properties and thermal conductance. Random voids were introduced into the solder pads of an LED assembly within a finite element model (FEM), leading to predictions of maximum shear stress and LED junction temperature. The findings correlate well with the experimental data, validating the FEM's applicability. Furthermore, a statistical analysis was conducted to explore the relationship between solder void fraction, position, and size, aiming to provide objective guidelines for analyzing soldered assembly tomography in reliability assessments.
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Recently, imaging systems with submicron image sensors have been increasingly adopting the Quad Bayer color filter array (CFA) owing to its high sensitivity under low illumination conditions when pixel binning techniques are employed. Conversely, under sufficient illumination conditions, direct demosaicing methods are required for the Quad Bayer color filter array to obtain a full-resolution color image. However, the Quad Bayer color filter array is more susceptible to aliasing artifacts because of its structural disadvantages compared to the Bayer color filter array. In this paper, we propose the multi-frame demosaicing method to address this problem. The proposed method assesses local spatial contributions within local windows at each pixel to reconstruct the lost spatial resolution caused by aliasing. Additionally, we utilize the color difference domain to exploit inter-channel correlations, aiming to alleviate color artifacts and enhance spatial resolution. The experimental results demonstrate that our proposed method outperforms other methods, both quantitatively and qualitatively, including single-frame-based demosaicing methods and another multi-frame demosaicing method with pixel binning techniques.
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Objective: The objectives were to validate a previously published equation for estimating basal endogenous losses (BEL) of crude protein (CP) in pigs fed nitrogen-free diets and to develop prediction equations for BEL of CP and amino acids (AA). Methods: A total of 139 observations from 123 experiments in 117 papers that determined the BEL of CP and AA in pigs were collected. For the validation of the previous equation for the BEL of CP, 94 observations that were not used for developing the previous equation were used. All observations were used to develop novel equations for estimating BEL of CP in pigs based on the initial body weight (IBW). Results: The validation study indicated that the slope for BEL of CP, representing a linear bias, was less than zero (-0.56; SE = 0.130; p<0.001). The intercept for BEL of CP, representing a mean bias, was less than zero (-3.21; SE = 0.488; p<0.001). The models for estimating BEL of CP (g/kg dry matter intake) in pigs fed a nitrogen-free diet were developed: 20.36 - 0.077 × IBW with R2 = 0.11 and p<0.001 and 20.80 × e(-0.00475 × IBW) with R2 = 0.12 and p<0.001. Novel linear models for estimating BEL of AA were developed using BEL of CP as the independent variable. Conclusion: The accuracy of the previous equation for estimating BEL of CP in pigs has been improved by reflecting additional data from recent publications. In the novel linear models for estimating BEL of AA of pigs, BEL of CP was used as an independent variable.
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To mimic the homeostatic functionality of biological neurons, a split-gate field-effect transistor (S-G FET) with a charge trap layer is proposed within a neuron circuit. By adjusting the number of charges trapped in the Si3N4 layer, the threshold voltage (Vth) of the S-G FET changes. To prevent degradation of the gate dielectric due to program/erase pulses, the gates for read operation and Vth control were separated through the fin structure. A circuit that modulates the width and amplitude of the pulse was constructed to generate a Program/Erase pulse for the S-G FET as the output pulse of the neuron circuit. By adjusting the Vth of the neuron circuit, the firing rate can be lowered by increasing the Vth of the neuron circuit with a high firing rate. To verify the performance of the neural network based on S-G FET, a simulation of online unsupervised learning and classification in a 2-layer SNN is performed. The results show that the recognition rate was improved by 8% by increasing the threshold of the neuron circuit fired.
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The marine dinoflagellate Alexandrium is known to form harmful algal blooms, and at least 14 species within the genus can produce saxitoxins (STXs). STX biosynthesis genes (sxt) are individually revealed in toxic dinoflagellates; however, the evolutionary history remains controversial. Herein, we determined the transcriptome sequences of toxic Alexandrium (A. catenella and A. pacificum) and non-toxic Alexandrium (A. fraterculus and A. fragae) and characterized their sxt by focusing on evolutionary events and STX production. Comparative transcriptome analysis revealed higher homology of the sxt in toxic Alexandrium than in non-toxic species. Notably, non-toxic Alexandrium spp. were found to have lost two sxt core genes, namely sxtA4 and sxtG. Expression levels of 28 transcripts related to eight sxt core genes showed that sxtA, sxtG, and sxtI were relatively high (>1.5) in the toxic group compared to the non-toxic group. In contrast, the non-toxic group showed high expression levels in sxtU (1.9) and sxtD (1.7). Phylogenetic tree comparisons revealed distinct evolutionary patterns between 28S rDNA and sxtA, sxtB, sxtI, sxtD, and sxtU. However, similar topology was observed between 28S rDNA, sxtS, and sxtH/T. In the sxtB and sxtI phylogeny trees, toxic Alexandrium and cyanobacteria were clustered together, separating from non-toxic species. These suggest that Alexandrium may acquire sxt genes independently via horizontal gene transfer from toxic cyanobacteria and other multiple sources, demonstrating monocistronic transcripts of sxt in dinoflagellates.
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Dinoflagelados , Filogenia , Saxitoxina , Transcriptoma , Dinoflagelados/genética , Dinoflagelados/metabolismo , Saxitoxina/genética , Saxitoxina/biosíntesis , Perfilación de la Expresión Génica , Evolución MolecularRESUMEN
Toxic dinoflagellate Alexandrium can produce saxitoxins (STXs) and cause paralytic shellfish poisoning (PSP), and thus they are monitored for environmental safety management. Microscopic discrimination of dinoflagellates is difficult to distinguish between toxic and non-toxic species due to their similar morphology. Meanwhile, an alternative quantitative PCR (qPCR) assay is sensitive, rapid, and cost-effective for harmful species monitoring. Herein, we developed a novel qPCR assay to detect the STXs biosynthesis gene sxtB of Alexandrium catenella and A. pacificum, the leading cause of PSP outbreaks in Asian coasts and worldwide. The newly designed sxtB TaqMan probes target the species without any positive signal in other relative dinoflagellates. Deming regression analysis revealed that the sxtB copy number of A. catenella and A. pacificum was 3.6 and 4.1 copies per cell, respectively. During the blooming periods (April 13th-14th, 2020), only A. catenella cells were detected through the qPCR assay, ranging from 5.0 × 10 to 2.5 × 104 eq cells L-1. In addition, sxtB qPCR quantified more accurately compared to large subunit (LSU) rRNA targeting qPCR assay that overestimate cell density. Besides, the sensitivity of sxtB was higher compared to the microscope when the species were rarely present (5.0 × 102 cells L-1). These suggest that the sxtB qPCR assay can be applied to toxic Alexandrium monitoring in the Korean coast, even in the early stage of bloomings.
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Dinoflagelados , Reacción en Cadena en Tiempo Real de la Polimerasa , Saxitoxina , Dinoflagelados/genética , Saxitoxina/genética , Saxitoxina/biosíntesis , República de Corea , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Floraciones de Algas NocivasRESUMEN
The marine dinoflagellate Alexandrium is known to form harmful algal blooms (HABs) and produces saxitoxin (STX) and its derivatives (STXs) that cause paralytic shellfish poisoning (PSP) in humans. Cell growth and cellular metabolism are affected by environmental conditions, including nutrients, temperature, light, and the salinity of aquatic systems. Abiotic factors not only engage in photosynthesis, but also modulate the production of toxic secondary metabolites, such as STXs, in dinoflagellates. STXs production is influenced by a variety of abiotic factors; however, the relationship between the regulation of these abiotic variables and STXs accumulation seems not to be consistent, and sometimes it is controversial. Few studies have suggested that abiotic factors may influence toxicity and STXs-biosynthesis gene (sxt) regulation in toxic Alexandrium, particularly in A. catenella, A. minutum, and A. pacificum. Hence, in this review, we focused on STXs production in toxic Alexandrium with respect to the major abiotic factors, such as temperature, salinity, nutrients, and light intensity. This review informs future research on more sxt genes involved in STXs production in relation to the abiotic factors in toxic dinoflagellates.
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Dinoflagelados , Saxitoxina , Dinoflagelados/genética , Dinoflagelados/metabolismo , Saxitoxina/genética , Saxitoxina/biosíntesis , Saxitoxina/metabolismo , Saxitoxina/toxicidad , Floraciones de Algas Nocivas , Salinidad , Intoxicación por MariscosRESUMEN
Extracellular vesicles play an important role in intercellular communication, with the potential to serve as biomaterials for nanocarriers. Combining such extracellular vesicles and liposomes results in advanced drug delivery carriers. In this study, we attempted to fabricate hybrid vesicles using a membrane fusion method and incorporated an anticancer drug. As a result, we successfully prepared nanosized uniform hybrid vesicles and evaluated their physicochemical characteristics and intracellular uptake mechanisms via endocytosis in various cell lines. Compared to liposomes, the hybrid vesicles showed better physical properties and a relatively higher reduction in cell viability, which was presumably dependent on the specific cell type. These findings suggest that fusion-based hybrid vesicles offer a novel strategy for delivering therapeutic agents and provide insights into the types of extracellular vesicles that are useful in fabricating hybrid vesicles to develop an advanced drug delivery system.
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Earlier studies have validated the isolation of extended-spectrum beta-lactamase-producing Salmonella (ESBL-Sal) strains from food. While poultry is recognized as a reservoir for Salmonella contamination, pertinent data regarding ESBL-Sal remains limited. Consequently, the Ministry of Food and Drug Safety has isolated Salmonella spp. from retail meat and evaluated their antibiotic susceptibility and genetic characteristics via whole-genome sequencing. To further elucidate these aspects, this study investigates the prevalence, antibiotic resistance profiles, genomic characteristics, and homology of ESBL-Sal spp. obtained from livestock-derived products in South Korean retail outlets. A total of 653 Salmonella spp. were isolated from 1,876 meat samples, including 509 beef, 503 pork, 555 chicken, and 309 duck samples. The prevalence rates of Salmonella were 0.0%, 1.4%, 17.5%, and 28.2% in the beef, pork, chicken, and duck samples, respectively. ESBL-Sal was exclusively identified in poultry meat, with a prevalence of 1.4% in the chicken samples (8/555) and 0.3% in the duck samples (1/309). All ESBL-Sal strains carried the blaCTX-M-1 gene and exhibited resistance to ampicillin, ceftiofur, ceftazidime, nalidixic acid, and tetracycline. Eight ESBL-Sal isolates were identified as S. Enteritidis with sequence type (ST) 11. The major plasmid replicons of the Enteritidis-ST11 strains were IncFIB(S) and IncFII(S), carrying antimicrobial resistance genes (ß-lactam, tetracycline, and aminoglycoside) and 166 virulence factor genes. The results of this study provide valuable insights for the surveillance and monitoring of ESBL-Sal in South Korean food chain.
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Antibacterianos , Pollos , Patos , Microbiología de Alimentos , Carne , Pruebas de Sensibilidad Microbiana , Salmonella , beta-Lactamasas , beta-Lactamasas/genética , Animales , República de Corea , Salmonella/genética , Salmonella/aislamiento & purificación , Salmonella/enzimología , Salmonella/efectos de los fármacos , Carne/microbiología , Antibacterianos/farmacología , Pollos/microbiología , Patos/microbiología , Bovinos , Porcinos/microbiología , Secuenciación Completa del Genoma , Farmacorresistencia Bacteriana Múltiple/genética , Prevalencia , Aves de Corral/microbiología , Plásmidos/genéticaRESUMEN
Introduction: The therapeutic potential of phytoncide fragrances may be optimal for patients with mild cognitive impairment (MCI) that display complex symptomatology. This study aimed to explore the clinical value of phytoncide by evaluating its electrophysiological effects in patients with MCI. Materials and Methods: This was a double-blind, randomized controlled trial. A total of 24 community-dwelling patients were randomly assigned to either a phytoncide or no-odor group. Participants wore a dental mask, for 30 min at rest that had either the fragrance stimulus or water added to it. The quantitative electroencephalography (EEG) during the resting state was recorded before and after a single intervention. Results: There were significant interaction effects in absolute EEG-power values in the occipital (F = 6.52, p = 0.018) and parietal (F = 5.41, p = 0.030) left hemisphere at ß frequency. Phytoncide odor significantly decreased low and high ß activity in the occipital (corrected p = 0.009) and parietal (corrected p = 0.047) left hemisphere, respectively. In source localization, phytoncide odor significantly decreased deep source activation in the left inferior and middle frontal gyri at ß 2 frequency band compared with the no-odor group (threshold = 4.25, p < 0.05). Conclusions: Reductions in ß, indicative of anxiety, depression, and stress, suggest relief from emotion-related symptoms that are common in patients with MCI. Trial Registration: Clinical Trials Registry Korea (registration: KCT0007317).
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Herein, we proposed a label-free method to identify RNase H activity by utilizing in vitro transcription of fluorogenic light-up aptamers. In this work, we employed the specially designed two pivotal components of the hairpin substrate probe (HP) containing an RNA/DNA chimeric stem region and the template probe (TP) as a transcription template, and the RNase H activity was made to lead to the formation of a complete ds T7 promoter. T7 RNA polymerase could then promote in vitro transcription to generate numerous light-up RNA aptamers that result in significant fluorescence enhancements upon binding to the cognate fluorogenic dye. By leveraging this deliberate design principle, we identified RNase H activity ultrasensitively as low as 0.000156 U mL-1 with excellent specificity against non-target enzymes. We further demonstrated that the strategy can also reliably identify RNase H activity in heterogeneous biological samples such as cell lysates, ensuring its robust practical applicability. This work would provide invaluable insight for the development of innovative biosensing systems utilizing in vitro transcription of light-up aptamers, and it could be broadened to construct other assays by appropriately redesigning the HPs.
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We herein present a multifunctional self-priming hairpin probe-based isothermal amplification, termed MSH, enabling one-pot detection of target nucleic acids. The sophisticatedly designed multifunctional self-priming hairpin (MSH) probe recognizes the target and rearranges to prime itself, triggering the amplification reaction powered by the continuously repeated extension, nicking, and target recycling. As a consequence, a large number of double-stranded DNA (dsDNA) amplicons are produced that could be monitored in real-time using a dsDNA-intercalating dye. Based on this unique design approach, the nucleocapsid (N) and the open reading frame 1 ab (ORF1ab) genes of SARS-CoV-2 were successfully detected down to 1.664 fM and 0.770 fM, respectively. The practical applicability of our method was validated by accurately diagnosing 60 clinical samples with 93.33% sensitivity and 96.67% specificity. This isothermal one-pot MSH technique holds great promise as a point-of-care testing protocol for the reliable detection of a wide spectrum of pathogens, particularly in resource-limited settings.
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Técnicas Biosensibles , COVID-19 , Ácidos Nucleicos , Humanos , COVID-19/diagnóstico , Prueba de COVID-19 , Técnicas de Amplificación de Ácido Nucleico/métodos , SARS-CoV-2/genética , Técnicas Biosensibles/métodos , Sensibilidad y EspecificidadRESUMEN
Recent progress in high-throughput sequencing technologies has dramatically increased availability of genome data for prokaryotes and eukaryotes. Dinoflagellates have distinct chromosomes and a huge genome size, which make their genomic analysis complicated. Here, we reviewed the nuclear genomes of core dinoflagellates, focusing on the genome and cell size. Till now, the genome sizes of several dinoflagellates (more than 25) have been measured by certain methods (e.g., flow cytometry), showing a range of 3-250 pg of genomic DNA per cell. In contrast to their relatively small cell size, their genomes are huge (about 1-80 times the human haploid genome). In the present study, we collected the genome and cell size data of dinoflagellates and compared their relationships. We found that dinoflagellate genome size exhibits a positive correlation with cell size. On the other hand, we recognized that the genome size is not correlated with phylogenetic relatedness. These may be caused by genome duplication, increased gene copy number, repetitive non-coding DNA, transposon expansion, horizontal gene transfer, organelle-to-nucleus gene transfer, and/or mRNA reintegration into the genome. Ultimate verification of these factors as potential causative mechanisms would require sequencing of more dinoflagellate genomes in the future.
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Dinoflagelados , Humanos , Filogenia , Dinoflagelados/genética , Genoma/genética , Evolución Biológica , ADNRESUMEN
INTRODUCTION: The aim of the present study was to evaluate the characteristics of brain injury and to assess the relationship between them and treatment outcomes in patients with traumatic benign paroxysmal positional vertigo (t-BPPV). MATERIALS AND METHODS: Sixty-three consecutive patients who were diagnosed with BPPV within 2 weeks after head trauma were included. RESULTS: Cerebral concussion, intracranial hemorrhages (ICH), skull fracture without ICH, and hemorrhagic contusion were observed in 68%, 24%, 5%, and 3% of t-BPPV patients, respectively. BPPV with single canal involvement was observed in 52 (83%) patients and that with multiple canal involvement was observed in 11 (17%) patients. The number of treatment sessions was not significantly different according to the cause of head trauma (p = 0.252), type of brain injury (p = 0.308) or location of head trauma (p = 0.287). The number of recurrences was not significantly different according to the cause of head trauma (p = 0.308), type of brain injury (p = 0.536) or location of head trauma (p = 0.138). CONCLUSION: The present study demonstrated that there were no significant differences in treatment sessions until resolution and the mean number of recurrences according to the type of brain injury.
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Conmoción Encefálica , Lesiones Encefálicas , Traumatismos Craneocerebrales , Humanos , Vértigo Posicional Paroxístico Benigno/diagnóstico , Vértigo Posicional Paroxístico Benigno/etiología , Vértigo Posicional Paroxístico Benigno/terapia , Traumatismos Craneocerebrales/complicaciones , Lesiones Encefálicas/complicaciones , Conmoción Encefálica/complicaciones , Resultado del TratamientoRESUMEN
BACKGROUND: Frailty, a decline in physical and cognitive reserve capacity, renders patients susceptible to various stressors and has been linked to adverse outcomes and increased healthcare utilization. This study aimed to determine whether ultrasound measurements of the rectus abdominis (RA) and biceps brachii (BB) could predict frailty in patients scheduled for total knee arthroplasty. METHODS: Frailty was assessed using the Clinical Frailty Scale in adults aged ≥60 years. Ultrasound measurements of the rectus abdominis, BB, and quadriceps femoris muscles, along with thigh circumference measurements, were obtained before surgery. The predictive ability of the unadjusted and BMI- and body surface area (BSA)-adjusted measurements were evaluated using receiver operating characteristic curve analysis and area under the curve (AUC) values. Postoperative outcomes, such as admission to the intensive care unit or skilled nursing facility, delirium, falls, re-hospitalization, and 30-day mortality were recorded. RESULTS: We analyzed data from 148 patients. BB thickness provided a fair prediction of frailty. Average measurements of both BB adjusted for BMI (0.708, 95% CI 0.602-0.814; P<0.001), and BSA (0.708, 95% CI 0.598-0.817; P<0.001) had the highest AUC values. RA muscle measurements could not discriminate frailty. The BMI-adjusted measurements for: right quadriceps femoris thickness (AUC 0.614, 95% CI 0.503-0.725; P=0.044), left thigh circumference (AUC 0.648, 95% CI 0.528-0.769; P=0.016), and average thigh circumference (AUC 0.630, 95% CI 0.511-0.750; P=0.033) had statistically significant but poor AUC values. CONCLUSIONS: Preoperative ultrasound measurements of the bilateral BB can fairly predict frailty in patients scheduled for total knee arthroplasty.
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Artroplastia de Reemplazo de Rodilla , Fragilidad , Anciano , Adulto , Humanos , Fragilidad/diagnóstico por imagen , Anciano Frágil , Hospitalización , Músculo EsqueléticoRESUMEN
We present a label-free colorimetric CRISPR/Cas-based method enabling affordable molecular diagnostics for SARS-CoV-2. This technique utilizes 3,3'-diethylthiadicarbocyanine iodide (DISC2(5)) which exhibits a distinct color transition from purple to blue when it forms dimers by inserting into the duplex of the thymidine adenine (TA) repeat sequence. Loop-mediated isothermal amplification (LAMP) or recombinase polymerase amplification (RPA) was used to amplify target samples, which were subsequently subjected to the CRISPR/Cas12a system. The target amplicons would activate Cas12a to degrade nearby TA repeat sequences, preserving DISC2(5) in its free form to display purple as opposed to blue in the absence of the target. Based on this design approach, SARS-CoV-2 RNA was colorimetrically detected very sensitively down to 2 copies/µL, and delta and omicron variants of SARS-CoV-2 were also successfully identified. The practical diagnostic utility of this method was further validated by reliably identifying 179 clinical samples including 20 variant samples with 100% clinical sensitivity and specificity. This technique has the potential to become a promising CRISPR-based colorimetric platform for molecular diagnostics of a wide range of target pathogens.
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Técnicas Biosensibles , COVID-19 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Sistemas CRISPR-Cas/genética , Colorimetría , ARN Viral , Adenina , Técnicas de Amplificación de Ácido NucleicoRESUMEN
OBJECTIVES: When air irrigation is used for caloric stimulation in patients with a perforated ear, warm irrigation may elicit a nystagmus that initially beats in the opposite direction of what is expected for warm irrigations, which is referred to as "caloric inversion". This study aimed to investigate the disease group in which caloric inversion appeared in patients who underwent caloric testing and to classify the patterns of caloric inversion. METHODS: We conducted a retrospective review of bithermal caloric test results that were collected in our dizziness clinic between 2005 and 2022. Caloric inversion was defined when nystagmus induced by caloric stimulation appeared in the opposite direction to that expected. The incidence of caloric inversion among all patients who underwent bithermal caloric tests was calculated. To confirm the clinical diagnoses of the patients with caloric inversion, their clinical records were reviewed. RESULTS: Out of 9923 patients who underwent bithermal caloric tests, 29 patients (0.29%) showed a caloric inversion. The most common clinical diagnosis was chronic otitis media (21 of 29, 72%). Of the 21 patients with chronic otitis media, 20 patients showed a caloric inversion by warm air irrigation and one patient showed caloric inversion by cold air stimulation. Patients with clinical diagnoses other than chronic otitis media such as sudden sensorineural hearing loss, benign paroxysmal vertigo of childhood and recurrent vestibulopathy showed caloric inversion by warm air irrigation. Caloric inversion by warm water irrigation was observed in patients with lateral semicircular canal cupulopathy and recurrent vestibulopathy. Two patients (one with Meniere's disease and one with age-related dizziness) showed caloric inversion by cold water irrigation. CONCLUSION: Caloric inversion can be observed in various diseases other than chronic otitis media with tympanic membrane perforation. Special care should be taken in the interpretation of caloric test results. LEVEL OF EVIDENCE: Level 4.