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1.
Opt Express ; 32(6): 9800-9808, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571205

RESUMEN

A special differential interferometer consisting of two gratings was developed for diagnostics of plasma density. Compared with other differential interferometers, our system has an important advantage that the shear distance, shear direction, and fringe width can be adjusted independently, enabling easy control of the parameters. This feature allows precise tuning of the two probe beams in the interferometer for rigorous differential phase diagnosis and more accurate information of the plasma density can be obtained. The double-grating-based differential interferometer was tested for diagnostics of the laser-produced plasma which was generated by focusing a 1 TW/35 fs Ti:sapphire laser pulse in a gas jet with a 100 µm orifice diameter. It was confirmed that our differential interferometer can provide more reliable and accurate plasma density information, especially for plasmas with a high spatial gradient in density.

2.
Front Neurol ; 15: 1342108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450068

RESUMEN

Background: Eye movement tests remain significantly underutilized in emergency departments and primary healthcare units, despite their superior diagnostic sensitivity compared to neuroimaging modalities for the differential diagnosis of acute vertigo. This underutilization may be attributed to a potential lack of awareness regarding these tests and the absence of appropriate tools for detecting nystagmus. This study aimed to develop a nystagmus measurement algorithm using a lightweight deep-learning model that recognizes the ocular regions. Method: The deep learning model was used to segment the eye regions, detect blinking, and determine the pupil center. The model was trained using images extracted from video clips of a clinical battery of eye movement tests and synthesized images reproducing real eye movement scenarios using virtual reality. Each eye image was annotated with segmentation masks of the sclera, iris, and pupil, with gaze vectors of the pupil center for eye tracking. We conducted a comprehensive evaluation of model performance and its execution speeds in comparison to various alternative models using metrics that are suitable for the tasks. Results: The mean Intersection over Union values of the segmentation model ranged from 0.90 to 0.97 for different classes (sclera, iris, and pupil) across types of images (synthetic vs. real-world images). Additionally, the mean absolute error for eye tracking was 0.595 for real-world data and the F1 score for blink detection was ≥ 0.95, which indicates our model is performing at a very high level of accuracy. Execution speed was also the most rapid for ocular object segmentation under the same hardware condition as compared to alternative models. The prediction for horizontal and vertical nystagmus in real eye movement video revealed high accuracy with a strong correlation between the observed and predicted values (r = 0.9949 for horizontal and r = 0.9950 for vertical; both p < 0.05). Conclusion: The potential of our model, which can automatically segment ocular regions and track nystagmus in real time from eye movement videos, holds significant promise for emergency settings or remote intervention within the field of neurotology.

3.
Int J Mol Sci ; 25(5)2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38473916

RESUMEN

Phalaenopsis orchids are one of the most popular ornamental plants. More than thirty orchid viruses have been reported, and virus-infected Phalaenopsis orchids significantly lose their commercial value. Therefore, the development of improved viral disease detection methods could be useful for quality control in orchid cultivation. In this study, we first utilized the MinION, a portable sequencing device based on Oxford Nanopore Technologies (ONT) to rapidly detect plant viruses in Phalaenopsis orchids. Nanopore sequencing revealed the presence of three plant viruses in Phalaenopsis orchids: odontoglossum ringspot virus, cymbidium mosaic virus, and nerine latent virus (NeLV). Furthermore, for the first time, we detected NeLV infection in Phalaenopsis orchids using nanopore sequencing and developed the reverse transcription-recombinase polymerase amplification (RT-RPA)-CRISPR/Cas12a method for rapid, instrument-flexible, and accurate diagnosis. The developed RT-RPA-CRISPR/Cas12a technique can confirm NeLV infection in less than 20 min and exhibits no cross-reactivity with other viruses. To determine the sensitivity of RT-RPA-CRISPR/Cas12a for NeLV, we compared it with RT-PCR using serially diluted transcripts and found a detection limit of 10 zg/µL, which is approximately 1000-fold more sensitive. Taken together, the ONT platform offers an efficient strategy for monitoring plant viral pathogens, and the RT-RPA-CRISPR/Cas12a method has great potential as a useful tool for the rapid and sensitive diagnosis of NeLV.


Asunto(s)
Amaryllidaceae , Infección Latente , Secuenciación de Nanoporos , Orchidaceae , Sistemas CRISPR-Cas , Reacciones Cruzadas , Recombinasas
4.
Curr Probl Diagn Radiol ; 53(3): 405-414, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38246795

RESUMEN

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.


Asunto(s)
Malformación de Arnold-Chiari , Escoliosis , Siringomielia , Humanos , Adolescente , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Malformación de Arnold-Chiari/diagnóstico por imagen , Malformación de Arnold-Chiari/cirugía , Imagen por Resonancia Magnética , Siringomielia/diagnóstico por imagen , Siringomielia/cirugía , Tamizaje Masivo , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/cirugía
5.
Curr Probl Diagn Radiol ; 53(3): 415-421, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38262798

RESUMEN

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.


Asunto(s)
Malformación de Arnold-Chiari , Defectos del Tubo Neural , Escoliosis , Neoplasias de la Médula Espinal , Humanos , Adolescente , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Defectos del Tubo Neural/diagnóstico por imagen , Defectos del Tubo Neural/patología , Malformación de Arnold-Chiari/diagnóstico por imagen , Malformación de Arnold-Chiari/patología , Imagen por Resonancia Magnética , Neoplasias de la Médula Espinal/patología , Médula Espinal/diagnóstico por imagen , Columna Vertebral/patología
6.
J Audiol Otol ; 28(1): 1-9, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38254303

RESUMEN

Hearing thresholds provide essential information and references about the human auditory system. This study aimed to identify changing trends in distributions of hearing threshold levels across ages by comparing the International Organization for Standardization (ISO) 7029 and newly available data after publishing ISO 7029. To compare ISO 7029 and newly available hearing threshold data after publishing ISO 7029, four country-specific datasets that presented average hearing threshold levels under conditions similar to ISO 7029 were utilized. For frequencies between 125 Hz and 8,000 Hz, the deviations of hearing threshold values by ages from the hearing threshold of the youngest age group for each data point were utilized. For frequencies from 9,000 Hz to 12,500 Hz, the median threshold information was utilized. Hearing threshold data reported after publishing ISO 7029 from the four countries were mostly similar to the ISO 7029 data but tended to deviate in some age groups and sexes. As national hearing threshold trends change, the following ISO 7029 revision suggests the need to integrate hearing threshold data from different countries.

9.
J Audiol Otol ; 27(4): 169-180, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37872752

RESUMEN

This study explores the internal standards for hearing tests and benefits of implementing international standard protocols, including the International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC), and discusses how ISO and IEC standards provide a framework for designing, calibrating, assessing hearing test instruments and methods, and exchanging and comparing data globally. ISO and IEC standards for hearing tests improve accuracy, reliability, and consistency of test results by applying standardized methods and environments. Moreover, they promote international harmonization and data interoperability, enabling information exchange and research collaboration. Those standards for hearing tests are beneficial but have challenges and limitations, such as variation in equipment and calibration, lag in updating standards, variation in implementation and compliance, and lack of coverage of clinical aspects, cultural diversity, and linguistic diversity. These affect the quality and interpretation of test results. Adapting ISO or IEC standards locally would improve their applicability and acceptability, while balancing customization and compatibility with global standards.

10.
ACS Omega ; 8(42): 39279-39287, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37901540

RESUMEN

Poly(propylene carbonate) (PPC) polyol is an environmentally sustainable material derived from abundant and renewable greenhouse gas, CO2. Optimizing their synthesis and properties is crucial to their application in the production of polyurethane products. In this study, we synthesized PPC polyols with varying carbonate contents using heterogeneous Zn/Co double metal cyanide (DMC) catalysts, which were prepared with poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123) as an effective complexing agent. Analysis of the influence of calcination temperature revealed that the DMC-P123 catalyst calcined at 100 °C exhibited superior catalytic performance owing to reduced crystallinity and enhanced formation of the monoclinic phase. Additionally, by precisely controlling the CO2 pressure, high propylene carbonate contents of up to 32.8 wt % in the polyol structure were achieved. The increased carbonate content enhanced the intermolecular attraction between polyol chains, thereby promoting hydrogen bonding and significantly modulating the rheological properties of the polyol. The novel findings of this study establish a solid foundation for the synthesis of CO2-based polyols with desirable properties, serving as alternatives to conventional petroleum-based polyols.

11.
Plant Pathol J ; 39(5): 449-465, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37817492

RESUMEN

Plants are challenged by various pathogens throughout their lives, such as bacteria, viruses, fungi, and insects; consequently, they have evolved several defense mechanisms. In addition, plants have developed localized and systematic immune responses due to biotic and abiotic stress exposure. Animals are known to activate DNA damage responses (DDRs) and DNA damage sensor immune signals in response to stress, and the process is well studied in animal systems. However, the links between stress perception and immune response through DDRs remain largely unknown in plants. To determine whether DDRs induce plant resistance to pathogens, Arabidopsis plants were treated with bleomycin, a DNA damage-inducing agent, and the replication levels of viral pathogens and growth of bacterial pathogens were determined. We observed that DDR-mediated resistance was specifically activated against viral pathogens, including turnip crinkle virus (TCV). DDR increased the expression level of pathogenesis-related (PR) genes and the total salicylic acid (SA) content and promoted mitogen-activated protein kinase signaling cascades, including the WRKY signaling pathway in Arabidopsis. Transcriptome analysis further revealed that defense- and SA-related genes were upregulated by DDR. The atm-2atr-2 double mutants were susceptible to TCV, indicating that the main DDR signaling pathway sensors play an important role in plant immune responses. In conclusion, DDRs activated basal immune responses to viral pathogens.

12.
Antioxidants (Basel) ; 12(8)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37627553

RESUMEN

The antioxidative proteolytic fraction, MA-1, was partially purified from Mycoleptodonoides aitchisonii. MA-1 was purified to homogeneity using a two-step procedure, which resulted in an 89-fold increase in specific activity and 42.5% recovery. SDS-PAGE revealed two proteins with a molecular weight of 48 kDa. The zymography results revealed proteolytic activity based on the MA-1 band. MA-1 was found to be stable in the presence of Na+, Ca2+, Fe3+, K+, and Mg2+. MA-1 was also stable in methanol, ethanol, and acetone, and its enzyme activity increased by 15% in SDS. MA-1 was inhibited by ethylenediaminetetra-acetic acid or ethylene glycol tetraacetic acid and exerted the highest specificity for the substrate, MeO-Suc-Arg-Pro-Tyr-pNA, for chymotrypsin. Accordingly, MA-1 belongs to the family of chymotrypsin-like metalloproteins. The optimum temperature was 40 °C and stability was stable in the range of 20 to 35 °C. The optimum pH and stability were pH 5.5 and pH 4-11. MA-1 exhibited stronger fibrinolytic activity than plasmin. MA-1 hydrolyzed the Aα, Bß, and γ chains of fibrinogen within 2 h. MA-1 exhibited an antithrombotic effect in animal models. MA-1 was devoid of hemorrhagic activity at a dose of 80,000 U/kg. Overall, our results show that M. aitchisonii produces an acid-tolerant and antioxidative chymotrypsin-like fibrinolytic enzyme, and M. aitchisonii containing MA-1 could be a beneficial functional material for the prevention of cardiovascular diseases and possible complications.

13.
Pharmaceutics ; 15(7)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37514071

RESUMEN

Acne vulgaris is a common skin disease characterized by increased sebum production, inflammation, and Cutibacterium acnes (CA: formerly Propionibacterium acnes) hyperproliferation in pilosebaceous follicles. This study evaluated the efficacy of FRO, a formula composed of fermented Rhus verniciflua Stokes and Orostachys japonicus, against acne pathogenesis via antimicrobial assessment and an in vitro analysis. Stimulated model cells treated with hormones, CA, or lipopolysaccharide (LPS) were designed based on the characteristics of acne pathogenesis, including inflammation and sebum hypersecretion. High-performance liquid chromatography, disc diffusion, MTS, and western blotting assays were used to examine potential anti-acne effects. FRO was determined to contain phenolics such as gallic acid, fisetin, quercetin, and kaempferol. FRO exerted antimicrobial activity against CA and inhibited reactive oxygen species production that was otherwise increased by LPS or CA in HaCaT cells. Additionally, FRO exerted anti-inflammatory effects by inhibiting iNOS, TNF-α, IL-6, p-STAT-3, and p-NF-κB, which were previously upregulated by LPS or CA in THP-1 and HaCaT cells. FRO inhibited lipogenesis induced by steroid hormones and CA by decreasing FAS and SREBP-1 levels in sebocytes. Additionally, FRO down-regulated the androgen receptor, 5α-reductase, SREBP-1, and FAS levels, which were upregulated by steroid hormone in LNCaP cells. Taken together, our findings suggest that FRO alleviates acne by inhibiting the growth of CA, inflammation, and excess sebum and could be used for functional cosmetics or acne treatments.

14.
Plants (Basel) ; 12(12)2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37375999

RESUMEN

Wheat (Triticum aestivum L.) is one of the most important staple crops in the world, along with maize and rice. More than 50 plant viruses are known to infect wheat worldwide. To date, there are no studies on the identification of viruses infecting wheat in Korea. Therefore, we investigated virome in wheat from three different geographical regions where wheat is mainly cultivated in Korea using Oxford Nanopore Technology (ONT) sequencing and Illumina sequencing. Five viral species, including those known to infect wheat, were identified using high-throughput sequencing strategies. Of these, barley virus G (BVG) and Hordeum vulgare endornavirus (HvEV) were consistently present in all libraries. Sugarcane yellow leaf virus (SCYLV) and wheat leaf yellowing-associated virus (WLYaV) were first identified in Korean wheat samples. The viruses identified by ONT and Illumina sequencing were compared using a heatmap. Though the ONT sequencing approach is less sensitive, the analysis results were similar to those of Illumina sequencing in our study. Both platforms served as reliable and powerful tools for detecting and identifying wheat viruses, achieving a balance between practicality and performance. The findings of this study will provide deeper insights into the wheat virosphere and further help improve disease management strategies.

15.
Plant Pathol J ; 39(3): 303-308, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37291770

RESUMEN

The global climate change and international trade have facilitated the movement of plants across borders, increasing the risk of introducing novel plant viruses in new territories. Ixora coccinea exhibited virus-like foliar symptoms, including mosaic and mild mottle. An Oxford Nanopore Technologies-based compact and portable MinION platform was used to identify the causal viral pathogen. The complete genome sequence of jasmine virus H (JaVH; 3867 nt, JaVH-CNU) was determined and found to share 88.4-90.3% nucleotide identity with that of Jasminum sambac JaVH isolate in China. Phylogenetic analysis based on the complete amino acid sequences of RNA-dependent RNA polymerase and coat protein revealed that JaVH-CNU was grouped separately with other JaVH isolates. This is the first report of a natural JaVH infection of >i<I. coccinea. The application of rapid nanopore sequencing for plant virus identification was demonstrated and is expected to provide accurate and rapid diagnosis for virus surveillance.

17.
Front Neurol ; 14: 1054105, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37006498

RESUMEN

The most common complaint in people with single-sided deafness (SSD) is difficulty in understanding speech in a noisy environment. Moreover, the neural mechanism of speech-in-noise (SiN) perception in SSD individuals is still poorly understood. In this study, we measured the cortical activity in SSD participants during a SiN task to compare with a speech-in-quiet (SiQ) task. Dipole source analysis revealed left hemispheric dominance in both left- and right-sided SSD group. Contrary to SiN listening, this hemispheric difference was not found during SiQ listening in either group. In addition, cortical activation in the right-sided SSD individuals was independent of the location of sound whereas activation sites in the left-sided SSD group were altered by the sound location. Examining the neural-behavioral relationship revealed that N1 activation is associated with the duration of deafness and the SiN perception ability of individuals with SSD. Our findings indicate that SiN listening is processed differently in the brains of left and right SSD individuals.

18.
Clin Exp Otorhinolaryngol ; 16(3): 217-224, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37080730

RESUMEN

OBJECTIVES: To train participants to localize sound using virtual reality (VR) technology, appropriate auditory stimuli that contain accurate spatial cues are essential. The generic head-related transfer function that grounds the programmed spatial audio in VR does not reflect individual variation in monaural spatial cues, which is critical for auditory spatial perception in patients with single-sided deafness (SSD). As binaural difference cues are unavailable, auditory spatial perception is a typical problem in the SSD population and warrants intervention. This study assessed the applicability of binaurally recorded auditory stimuli in VR-based training for sound localization in SSD patients. METHODS: Sixteen subjects with SSD and 38 normal-hearing (NH) controls underwent VR-based training for sound localization and were assessed 3 weeks after completing training. The VR program incorporated prerecorded auditory stimuli created individually in the SSD group and over an anthropometric model in the NH group. RESULTS: Sound localization performance revealed significant improvements in both groups after training, with retained benefits lasting for an additional 3 weeks. Subjective improvements in spatial hearing were confirmed in the SSD group. CONCLUSION: By examining individuals with SSD and NH, VR-based training for sound localization that used binaurally recorded stimuli, measured individually, was found to be effective and beneficial. Furthermore, VR-based training does not require sophisticated instruments or setups. These. RESULTS: suggest that this technique represents a new therapeutic treatment for impaired sound localization.

19.
J Korean Med Sci ; 38(12): e82, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36974396

RESUMEN

BACKGROUND: Many studies have examined the perception of musical emotion using excerpts from familiar music that includes highly expressed emotions to classify emotional choices. However, using familiar music to study musical emotions in people with acquired hearing loss could produce ambiguous results as to whether the emotional perception is due to previous experiences or listening to the current musical stimuli. To overcome this limitation, we developed new musical stimuli to study emotional perception without the effects of episodic memory. METHODS: A musician was instructed to compose five melodies with evenly distributed pitches around 1 kHz. The melodies were created to express the emotions of happy, sad, angry, tender, and neutral. To evaluate whether these melodies expressed the intended emotions, two methods were applied. First, we classified the expressed emotions of melodies with selected musical features from 60 features using genetic algorithm-based k-nearest neighbors. Second, forty-four people with normal hearing participated in an online survey regarding the emotional perception of music based on dimensional and discrete approaches to evaluate the musical stimuli set. RESULTS: Twenty-four selected musical features produced classification for intended emotions with an accuracy of 76%. The results of the online survey in the normal hearing (NH) group showed that the intended emotions were selected significantly more often than the others. K-means clustering analysis revealed that melodies with arousal and valence ratings corresponded to representative quadrants of interest. Additionally, the applicability of the stimuli was tested in 4 individuals with high-frequency hearing loss. CONCLUSION: By applying the individuals with NH, the musical stimuli were shown to classify emotions with high accuracy, as expressed. These results confirm that the set of musical stimuli can be used to study the perceived emotion in music, demonstrating the validity of the musical stimuli, independent of innate musical bias such as due to episodic memory. Furthermore, musical stimuli could be helpful for further studying perceived musical emotion in people with hearing loss because of the controlled pitch for each emotion.


Asunto(s)
Pérdida Auditiva , Música , Humanos , Música/psicología , Percepción Auditiva , Emociones , Ira
20.
Neuropsychologia ; 183: 108515, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-36792051

RESUMEN

Persons with single-sided deafness (SSD) typically complain about the impaired ability to locate sounds and to understand speech within background noise. However, the findings from previous studies suggest that paying attention to sounds could mitigate the degraded spatial and speech-in-noise perception. In the present study, we characterize the pattern of cortical activation depending on the side of deafness, and attentional modulation of neural responses to determine if it can assist better sound processing in people with SSD. For the active listening condition, adult subjects with SSD performed sound localization tasks. On the other hand, they watched movies without attending to speech stimuli during passive listening. The sensor-level global field power of N1 and source-level N1 activation were computed to compare the active- and passive-listening conditions and left- and right-sided deafness. The results show that attentional modulation differs depending on the side of deafness: active listening increased the cortical activity in individuals with left-sided deafness but not in those with right-sided deafness. At the source level, the attentional gain was more apparent in left-sided deafness in that paying attention enhanced brain activation in both hemispheres. In addition, SSD participants with larger cortical activities in the right primary auditory cortex had shorter durations of deafness. Our results indicate that the side of deafness can change top-down attentional processing in the auditory cortical pathway in SSD patients.


Asunto(s)
Corteza Auditiva , Implantes Cocleares , Sordera , Pérdida Auditiva Unilateral , Percepción del Habla , Adulto , Humanos , Corteza Auditiva/fisiología , Audición , Percepción Auditiva , Percepción del Habla/fisiología
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