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1.
Sci Adv ; 10(38): eadp2809, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39292769

RESUMEN

Biologically inspired artificial vision research has led to innovative robotic vision systems with low optical aberration, wide field of view, and compact form factor. However, challenges persist in object detection and recognition against complex backgrounds and varied lighting. Inspired by the feline eye, which features a vertically elongated pupil and tapetum lucidum, this study introduces an artificial vision system designed for superior object detection and recognition in a monocular framework. Using a slit-like elliptical aperture and a patterned metal reflector beneath a hemispherical silicon photodiode array, the system reduces excessive light and enhances photosensitivity. This design achieves clear focus under bright light and enhanced sensitivity in dim conditions. Theoretical and experimental analyses demonstrate the system's ability to filter redundant information and detect camouflaged objects in diverse lighting, representing a substantial advancement in monocular camera technology and the potential of biomimicry in optical innovations.

2.
ACS Appl Mater Interfaces ; 16(38): 51459-51468, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39264059

RESUMEN

The drive to enhance the operational durability and reliability of stretchable and wearable electronic and electrochemical devices has led to the exploration of self-healing materials that can recover from both physical and functional failures. In the present study, we fabricated a self-healable solid polymer electrolyte, referred to as an ionogel, using reversible hydrogen bonding between the ureidopyrimidone units of a block copolymer (BCP) network swollen in an ionic liquid (IL). The BCP consisted of poly(styrene-b-(methyl acrylate-r-ureidopyrimidone methacrylate)) [poly(S-b-(MA-r-UPyMA)], with the IL-phobic polystyrene forming micellar cores that were interconnected via intercorona hydrogen bonding between the ureidopyrimidone units. By precisely regulating the molecular weight and the composition of the hydrogen-bondable motifs, the mechanical, electrical, and self-healing characteristics of the ionogel were systematically evaluated. The resulting ionogel samples exhibited suitable stretchability, ionic conductivity, and room-temperature self-healability due to reversible hydrogen bonding. To highlight the applicability of the self-healing ionogel as a high-capacitance gate insulator, an electrolyte-gated transistor (EGT) was fabricated using a poly(3-hexylthiophene-2,5-diyl) semiconductor, and the performance of the EGT was fully recovered from a complete cut without any external stimuli.

3.
J Microbiol Biotechnol ; 34(9): 1836-1847, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39187447

RESUMEN

Polyethylene terephthalate (PET), one of the most widely used plastics in the world, causes serious environmental problems. Recently, scientists have been focused on the enzymatic degradation of PET, an environmentally friendly method that offers an attractive approach to the degradation and recycling of PET. In this work, PET hydrolase from Streptomyces sp. W2061 was biochemically characterized, and the biodegradation of PET was performed using the PET model substrate bis (2-hydroxyethyl terephthalate) (BHET). PET hydrolase has an isoelectric point of 5.84, and a molecular mass of about 50.31 kDa. The optimum pH and temperature were 7.0 and 40°C, respectively. LC-MS analysis of the enzymatic products showed that the PET hydrolase successfully degraded a single ester bond of BHET, leading to the formation of MHET. Furthermore, in silico characterization of the PET hydrolase protein sequence and its predicted three-dimensional structure was designed and compared with the well-characterized IsPETase from Ideonella sakaiensis. The structural analysis showed that the (Gly-x1-Ser-x2-Gly) serine hydrolase motif and the catalytic triad (Ser, Asp, and His) were conserved in all sequences. In addition, we integrated molecular dynamics (MD) simulations to analyze the variation in the structural stability of the PET hydrolase in the absence and presence of BHET. These simulations showed the formation of a stable complex between the PET hydrolase and BHET. To the best of our knowledge, this is the first study on Streptomyces sp. W2061 to investigate the BHET degradation activity of PET hydrolase, which has potential application in the biodegradation of plastics in the environment.


Asunto(s)
Biodegradación Ambiental , Hidrolasas , Tereftalatos Polietilenos , Streptomyces , Temperatura , Streptomyces/enzimología , Tereftalatos Polietilenos/metabolismo , Tereftalatos Polietilenos/química , Hidrolasas/metabolismo , Hidrolasas/química , Concentración de Iones de Hidrógeno , Especificidad por Sustrato , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Burkholderiales/enzimología , Burkholderiales/metabolismo , Secuencia de Aminoácidos , Peso Molecular , Simulación por Computador , Cinética , Punto Isoeléctrico , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/química
4.
Am J Vet Res ; 85(10)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39047767

RESUMEN

OBJECTIVE: To investigate whether liver compression (LC) could increase stroke volume (SV) by more than 15% in healthy, anesthetized dogs with hypovolemia and suggest LC as a novel method to evaluate fluid responsiveness. ANIMALS: 6 healthy Beagles. METHODS: This prospective, nonrandomized experimental study was conducted from November 2023 to February 2024. The dogs were anesthetized with isoflurane and mechanically ventilated under neuromuscular blockade. After instrumentation, the dogs underwent the following 4 experimental stages in a sequential, nonrandomized manner: stage 1, baseline; stage 2, 30% withdrawal of circulating blood volume; stage 3, 50% infusion of the collected blood; and stage 4, the remaining 50% infusion of the collected blood. At each stage, SV via pulmonary artery thermodilution and hemodynamic variables were measured before, during, and after the LC. RESULTS: In stage 2, LC significantly increased mean SV by 30%, from 6.9 to 9 mL/beat. Simultaneously, LC significantly increased mean arterial pressure by 11 mm Hg and mean central venous pressure by 2 mm Hg, while pulse pressure variation significantly decreased from 28% to 22%. In stages 1, 3, and 4, LC did not significantly change mean SV, mean arterial pressure, and pulse pressure variation; however, mean central venous pressure significantly increased during stage 3. CLINICAL RELEVANCE: This study demonstrates that LC at 22 mm Hg for 1 minute could increase SV more than 15% in anesthetized, hypovolemic dogs and LC could be used as a novel method to evaluate fluid responsiveness.


Asunto(s)
Hipovolemia , Animales , Perros , Hipovolemia/veterinaria , Hipovolemia/fisiopatología , Estudios Prospectivos , Masculino , Femenino , Hígado , Enfermedades de los Perros/fisiopatología , Enfermedades de los Perros/terapia , Volumen Sistólico , Fluidoterapia/veterinaria , Hemodinámica
5.
J Korean Med Sci ; 39(23): e179, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38887200

RESUMEN

BACKGROUND: This study compared hearing outcomes with use of personal sound amplification products (PSAPs) and hearing aids (HAs) in patients with moderate to moderately severe unilateral hearing loss. METHODS: Thirty-nine participants were prospectively enrolled, and randomly assigned to use either one HA (basic or premium type) or one PSAP (basic or high-end type) for the first 8 weeks and then the other device for the following 8 weeks. Participants underwent a battery of examinations at three visits, including sound-field audiometry, word recognition score (WRS), speech perception in quiet and in noise, real-ear measurement, and self-report questionnaires. RESULTS: Functional gain was significantly higher with HAs across all frequencies (P < 0.001). While both PSAPs and HAs improved WRS from the unaided condition, HAs were superior to PSAPs. The speech recognition threshold in quiet conditions and signal-to-noise ratio in noisy conditions were significantly lower in the HA-aided condition than in the PSAP-aided condition, and in the PSAP-aided condition than in the unaided condition. Subjective satisfaction also favored HAs than PSAPs in questionnaires, Abbreviated Profile of Hearing Aid Benefit, International Outcome Inventory for Hearing Aids, and Host Institutional Questionnaire. CONCLUSION: While PSAPs provide some benefit for moderate to moderately severe unilateral hearing loss, HAs are more effective. This underscores the potential role of PSAPs as an accessible, affordable first-line intervention in hearing rehabilitation, particularly for individuals facing challenges in accessing conventional HAs.


Asunto(s)
Estudios Cruzados , Audífonos , Pérdida Auditiva Unilateral , Percepción del Habla , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Encuestas y Cuestionarios , Pérdida Auditiva Unilateral/rehabilitación , Anciano , Adulto , Satisfacción del Paciente , Ruido , Relación Señal-Ruido
6.
Toxins (Basel) ; 16(6)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38922161

RESUMEN

Botulinum toxin A (BONT/A) injections play a central role in the treatment of upper limb spasticity in stroke patients. We proposed structured stretching exercises to enhance the effect of post-stroke spasticity relief of the upper limbs following BONT/A injections. A total of 43 patients who had a stroke with grade 2 spasticity or higher on the Modified Ashworth Scale (MAS) in their upper-limb muscles were randomly assigned to the intervention (n = 21) or control group (n = 22). The former received structured stretching exercises after their BONT/A injections for 20 min, 5 days per week, for 6 months at a hospital, while the others conducted self-stretching exercises at home. The outcome measures were assessed before the intervention (T0) and after three (T1) and six months (T2). Significantly greater improvements in the MAS scores of the elbows, wrists, and fingers were found in the intervention group's patients at T1 and T2. The behavioral outcome measures, including shoulder pain, activities of daily living, and quality of life, and our electrophysiological studies also showed a significantly higher enhancement in this patient group. In conclusion, the structured stretching exercises plus BONT/A injections for six months showed a superior effect in relieving post-stroke upper-limb spasticity compared to self-stretching exercises.


Asunto(s)
Toxinas Botulínicas Tipo A , Espasticidad Muscular , Ejercicios de Estiramiento Muscular , Accidente Cerebrovascular , Humanos , Espasticidad Muscular/tratamiento farmacológico , Espasticidad Muscular/etiología , Espasticidad Muscular/terapia , Masculino , Femenino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Toxinas Botulínicas Tipo A/administración & dosificación , Toxinas Botulínicas Tipo A/uso terapéutico , Anciano , Resultado del Tratamiento , Extremidad Superior , Fármacos Neuromusculares/administración & dosificación , Fármacos Neuromusculares/uso terapéutico , Actividades Cotidianas , Calidad de Vida , Rehabilitación de Accidente Cerebrovascular/métodos
7.
Vet Med Sci ; 10(4): e1508, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38889073

RESUMEN

A 6-month-old intact female mixed-breed kitten presented with severe exophthalmos of the left eye. Periocular lesions, including subconjunctival haemorrhage, third eyelid protrusion, and left eyelid oedema, were detected in the absence of globe retropulsion. The left intraocular pressure was increased, and ocular ultrasonography revealed ipsilateral retrobulbar fluid. Coagulation panels were markedly prolonged and severe anaemia was detected. Ultrasound-guided retrobulbar centesis performed to decrease intraocular pressure yielded blood. Based on the history and clinical findings, anticoagulant rodenticide intoxication was suspected. Treatment included partial tarsorrhaphy and the administration of topical antibiotics, artificial tears, and vitamin K1. Fresh whole blood and fresh frozen plasma were transfused for supportive therapy. Coagulation parameters improved after 7 days of hospitalisation. The periocular lesions resolved within 14 days, despite persistent optic nerve damage and blindness. This case report raises the possibility that anticoagulant rodenticide toxicity may result in retrobulbar haemorrhage in the absence of other typical cavitary bleeding. Although uncommon, anticoagulant rodenticide toxicity should be considered in cats with retrobulbar haemorrhage.


Asunto(s)
Anticoagulantes , Enfermedades de los Gatos , Hemorragia Retrobulbar , Rodenticidas , Animales , Femenino , Gatos , Rodenticidas/envenenamiento , Enfermedades de los Gatos/inducido químicamente , Hemorragia Retrobulbar/veterinaria , Hemorragia Retrobulbar/inducido químicamente , Hemorragia Retrobulbar/etiología
8.
Medicina (Kaunas) ; 60(6)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38929619

RESUMEN

Background and Objectives: Cervical radiculopathy (CR) manifests as pain and sensorimotor disturbances in the upper extremities, often resulting from nerve root compression due to intervertebral disc herniation, degenerative changes, or trauma. While conservative treatments are initially preferred, persistent or severe cases may require surgical intervention. Ultrasound-guided selective nerve root block (SNRB) has emerged as a promising intervention for alleviating symptoms and potentially obviating the need for surgery. This study evaluates the therapeutic efficacy of ultrasound-guided SNRB in managing chronic CR, aiming to determine its potential in symptom relief and delaying or avoiding surgical procedures. Materials and Methods: A retrospective analysis was conducted on 720 outpatients treated for CR between October 2019 and March 2022. After excluding patients with traumatic CR, previous surgeries, malignancies, progressive neurological symptoms requiring immediate surgery, or inadequate conservative treatment, 92 patients who had experienced cervical radicular pain for more than three months and had failed to improve after more than six weeks of conservative treatment with VAS scores ≥ 5 were included. The patients underwent single or multiple ultrasound-guided SNRB procedures, involving the injection of dexamethasone and lidocaine under real-time ultrasound guidance. Symptom severity was assessed at the baseline, and at 4, 8, and 12 weeks post-procedure using the Visual Analog Scale (VAS). The data collected included age, sex, presence of neck and/or radicular pain, physical examination findings, recurrence of symptoms, improvement in symptoms, and whether surgical intervention was ultimately required. Statistical analyses were performed to identify the factors associated with symptom improvement or recurrence. Results: Significant symptom improvement was observed in 69 (75.0%) participants post-SNRB, with 55 (79.7%) showing improvement at 4 weeks, 11 (15.9%) at 8 weeks, and 3 (4.4%) at 12 weeks. Symptom recurrence, defined by an increase in VAS score accompanied by a pain flare lasting at least 24 h after a pain-free interval of at least one month, was noted in 48 (52.2%) patients. The presence of combined neck and radicular pain was a significant predictor of recurrence (p = 0.008). No significant associations were found between symptom relief and factors such as age, gender, initial pain severity, or MRI findings. Conclusions: Ultrasound-guided SNRB effectively manages chronic CR, providing substantial symptom relief and potentially reducing the need for surgical intervention. This technique offers a promising conservative treatment option, especially given its real-time visualization advantages and minimal radiation exposure.


Asunto(s)
Bloqueo Nervioso , Radiculopatía , Ultrasonografía Intervencional , Humanos , Femenino , Masculino , Persona de Mediana Edad , Radiculopatía/tratamiento farmacológico , Estudios Retrospectivos , Bloqueo Nervioso/métodos , Ultrasonografía Intervencional/métodos , Adulto , Resultado del Tratamiento , Dimensión del Dolor/métodos , Anciano , Lidocaína/administración & dosificación , Lidocaína/uso terapéutico , Enfermedad Crónica , Dexametasona/administración & dosificación , Dexametasona/uso terapéutico
9.
Brain Sci ; 14(6)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38928546

RESUMEN

The gold standard test for diagnosing dysphagia is the videofluoroscopic swallowing study (VFSS). However, the accuracy of this test varies depending on the specialist's skill level. We proposed a VFSS-based artificial intelligence (AI) web application to diagnose dysphagia. Video from the VFSS consists of multiframe data that contain approximately 300 images. To label the data, the server separated them into frames during the upload and stored them as a video for analysis. Then, the separated data were loaded into a labeling tool to perform the labeling. The labeled file was downloaded, and an AI model was developed by training with You Only Look Once (YOLOv7). Using a utility called SplitFolders, the entire dataset was divided according to a ratio of training (70%), test (10%), and validation (20%). When a VFSS video file was uploaded to an application equipped with the developed AI model, it was automatically classified and labeled as oral, pharyngeal, or esophageal. The dysphagia of a person was categorized as either penetration or aspiration, and the final analyzed result was displayed to the viewer. The following labeling datasets were created for the AI learning: oral (n = 2355), pharyngeal (n = 2338), esophageal (n = 1480), penetration (n = 1856), and aspiration (n = 1320); the learning results of the YOLO model, which analyzed dysphagia using the dataset, were predicted with accuracies of 0.90, 0.82, 0.79, 0.92, and 0.96, respectively. This is expected to help clinicians more efficiently suggest the proper dietary options for patients with oropharyngeal dysphagia.

10.
Brain Sci ; 14(3)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38539604

RESUMEN

Toe grip strength has recently been suggested to play an essential role in maintaining balance and postural stability for ambulatory function in older populations. This study aimed to investigate its association with improving gait function three months after onset in patients with subacute stroke. This longitudinal cohort study included 98 first-ever stroke patients (67 ± 9 years, 56% female) within one month from the onset who could not ambulate independently. Functional outcome indicators, including toe grip strength, hand grip strength, knee extensor strength, Fugl-Meyer Assessment of Lower Extremity (FMA_LE), and the Postural Assessment Scale for Stroke (PASS), were assessed before and three months after the intervention. We analyzed the correlation between participants' gait function using a 10-meter walk test time and various functional indicators. Then, multiple linear regression analysis was used to investigate whether toe grip strength was related to the improvement of gait function. Correlation analysis revealed a significant positive correlation between the 10MWT time and toe grip strength ratio (affected/unaffected side), with a moderate effect size (r = -0.61, p <0.001). Multiple regression analysis with covariates showed a significant relationship between 10MWT time and toe grip strength ratio (ß = -0.113, p < 0.001), FMA_LE (ß = -1.315, p = 0.004), PASS (ß = -3.275, p <0.001), and age (ß = -0.159, p = 0.004). In conclusion, toe grip strength was an essential factor associated with ambulatory function improvement in subacute stroke patients three months after onset. Additional toe grip muscle strengthening rehabilitation treatment can be expected to help improve the ambulatory function of subacute stroke patients in the future.

11.
Medicine (Baltimore) ; 103(13): e37639, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38552083

RESUMEN

RATIONALE: Renal cell carcinoma (RCC) is the most common renal neoplasm, accounting for 2.4% of all cancers in Korea. Although the usual clinical manifestations of RCC include flank pain, hematuria, and palpable mass, RCC is generally characterized by a lack of early warning signs and is mostly discovered incidentally in advanced stage. This case report describes a 42-year-old Korean man diagnosed with giant RCC who presented with simple back pain. PATIENT CONCERNS: The clinical manifestation of a 42-year-old Korean man was chronic back pain. DIAGNOSES: Contrast-enhanced computed tomography showed a 19.1-cm sized heterogeneous enhancing mass on the right kidney and tumor thrombosis extending into inferior vena cava. INTERVENTION: Due to the large size of the tumor and extensive tumor thrombosis, the multidisciplinary team decided to administer neoadjuvant chemotherapy and an anticoagulant. Following 12 cycles of treatment with nivolumab and cabozantinib, he underwent a right radical nephrectomy with an adrenalectomy and tumor thrombectomy. OUTCOMES: Treatment was successful and posttreatment he started a cancer rehabilitation program. He was followed-up as an outpatient and no longer complains of back pain. LESSONS: RCC can manifest clinically as back pain, with diagnosis being difficult without appropriate imaging modalities. RCC should be included in the differential diagnosis of patients with low back pain, even at a young age.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Dolor de la Región Lumbar , Trombosis , Masculino , Humanos , Adulto , Carcinoma de Células Renales/complicaciones , Carcinoma de Células Renales/diagnóstico , Carcinoma de Células Renales/cirugía , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/patología , Neoplasias Renales/complicaciones , Neoplasias Renales/diagnóstico , Neoplasias Renales/cirugía , Riñón/patología , Vena Cava Inferior/diagnóstico por imagen , Vena Cava Inferior/patología , Trombosis/patología , Nefrectomía/métodos , Trombectomía/métodos
12.
Endocrinol Metab (Seoul) ; 39(2): 288-299, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38437824

RESUMEN

BACKGRUOUND: Current research has not investigated the effect of thyroid-stimulating hormone suppression therapy with levothyroxine on the risk for developing subsequent primary cancers (SPCs). This study aimed to investigate the association between levothyroxine dosage and the risk for SPCs in thyroid cancer patients. METHODS: We conducted a nationwide population-based retrospective cohort study form Korean National Health Insurance database. This cohort included 342,920 thyroid cancer patients between 2004 and 2018. Patients were divided into the non-levothyroxine and the levothyroxine groups, the latter consisting of four dosage subgroups according to quartiles. Cox proportional hazard models were performed to evaluate the risk for SPCs by adjusting for variables including cumulative doses of radioactive iodine (RAI) therapy. RESULTS: A total of 17,410 SPC cases were observed over a median 7.3 years of follow-up. The high-dose levothyroxine subgroups (Q3 and Q4) had a higher risk for SPC (adjusted hazard ratio [HR], 1.14 and 1.27; 95% confidence interval [CI], 1.05-1.24 and 1.17- 1.37; respectively) compared to the non-levothyroxine group. In particular, the adjusted HR of stomach (1.31), colorectal (1.60), liver and biliary tract (1.95), and pancreatic (2.48) cancers were increased in the Q4 subgroup. We consistently observed a positive association between high levothyroxine dosage per body weight and risk of SPCs, even after adjusting for various confounding variables. Moreover, similar results were identified in the stratified analyses according to thyroidectomy type and RAI therapy, as well as in a subgroup analysis of patients with good adherence. CONCLUSION: High-dose levothyroxine use was associated with increased risk of SPCs among thyroid cancer patients regardless of RAI therapy.


Asunto(s)
Supervivientes de Cáncer , Neoplasias de la Tiroides , Tiroxina , Humanos , Tiroxina/administración & dosificación , Tiroxina/uso terapéutico , Neoplasias de la Tiroides/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto , República de Corea/epidemiología , Supervivientes de Cáncer/estadística & datos numéricos , Anciano , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/etiología , Factores de Riesgo , Relación Dosis-Respuesta a Droga , Estudios de Cohortes , Estudios de Seguimiento
13.
Angew Chem Int Ed Engl ; 63(12): e202319707, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38294268

RESUMEN

Fast charging technology for electric vehicles (EVs), offering rapid charging times similar to conventional vehicle refueling, holds promise but faces obstacles owing to kinetic issues within lithium-ion batteries (LIBs). Specifically, the significance of cathode materials in fast charging has grown because Ni-rich cathodes are employed to enhance the energy density of LIBs. Herein, the mechanism behind the loss of fast charging capability of Ni-rich cathodes during extended cycling is investigated through a comparative analysis of Ni-rich cathodes with different microstructures. The results revealed that microcracks and the resultant cathode deterioration significantly compromised the fast charging capability over extended cycling. When thick rocksalt impurity phases form throughout the particles owing to electrolyte infiltration via microcracks, the limited kinetics of Li+ ions create electrochemically unreactive areas under high-current conditions, resulting in the loss of fast charging capability. Hence, preventing microcrack formation by tailoring microstructures is essential to ensure stability in fast charging capability. Understanding the relationship between microcracks and the loss of fast charging capability is essential for developing Ni-rich cathodes that facilitate stable fast charging upon extended cycling, thereby promoting widespread EV adoption.

14.
Sensors (Basel) ; 24(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38257660

RESUMEN

This paper presents the design of a low-noise amplifier (LNA) with a bypass mode for the n77/79 bands in 5G New Radio (NR). The proposed LNA integrates internal matching networks for both input and output, combining two LNAs for the n77 and n79 bands into a single chip. Additionally, a bypass mode is integrated to accommodate the flexible operation of the receiving system in response to varying input signal levels. For each frequency band, we designed a low-noise amplifier for the n77 band to expand the bandwidth to 900 MHz (3.3 GHz to 4.2 GHz) using resistive-capacitance (RC) feedback and series inductive-peaking techniques. For the n79 band, only the RC feedback technique was employed to optimize the performance of the LNA for its 600 MHz bandwidth (4.4 GHz to 5.0 GHz). Because wideband techniques can lead to a trade-off between gain and noise, causing potential degradation in noise performance, appropriate bandwidth design becomes crucial. The designed n77 band low-noise amplifier achieved a simulated gain of 22.6 dB and a noise figure of 1.7 dB. Similarly, the n79 band exhibited a gain of 21.1 dB and a noise figure of 1.5 dB with a current consumption of 10 mA at a 1.2 supply voltage. The bypass mode was designed with S21 of -3.7 dB and -5.0 dB for n77 and n79, respectively.

15.
J Am Vet Med Assoc ; 262(3): 364-369, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38134454

RESUMEN

OBJECTIVE: To measure the tracheal diameter and length in kittens using radiography and CT and to evaluate the concordance between measurements obtained with these 2 modalities. ANIMALS: 15 kittens with an estimated age of 12 weeks and mean body weight of 1.49 kg. METHODS: Radiographic and CT images were retrospectively evaluated to measure tracheal lengths and diameters. Tracheal diameters were measured at 5 different sites (A [at the level of the C2-3 intervertebral disk space], B [at the level of the C4-5 intervertebral disk space], C [at the cranial end of the manubrium sterni], D [at the level of the second rib], and E [1 cm cranial to the carina]) along the trachea. The cross-sectional area and transverse and vertical diameter ratios were calculated for each measurement site. RESULTS: The cross-sectional area was largest at site A and decreased from site C to site E. Based on the vertical diameter ratio, the tracheal shape was most circular at sites A and E, whereas from sites B to D, it was elliptical. The vertical diameters of the trachea on radiography and CT did not differ statistically significantly. However, the tracheal length measured on radiography was approximately 6 mm longer than that measured on CT (P < .05). CLINICAL RELEVANCE: Using the first rib as an anatomical reference, the placement of a cuffed endotracheal tube is recommended in kittens. In emergency situations, regression equations based on body weight may be helpful in predicting tracheal diameters.


Asunto(s)
Tomografía Computarizada por Rayos X , Tráquea , Femenino , Animales , Gatos , Tráquea/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/veterinaria , Peso Corporal , Intubación Intratraqueal/veterinaria
16.
Nutrients ; 15(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38068815

RESUMEN

Vitamin D (Vit D) affects musculoskeletal performance and central nervous system neuroprotection. We aimed to investigate the association between serum Vit D levels and short-term functional outcomes in patients with acute ischemic stroke. This study involved patients with acute ischemic stroke confirmed on brain MRI. The National Institutes of Health Stroke Scale (NIHSS) was used to assess initial stroke severity upon admission. We evaluated the functional outcomes using the Berg Balance Scale (BBS), Manual Function Test (MFT), Korean Mini-Mental State Examination (K-MMSE), Korean version of the modified Barthel Index (K-MBI) within three weeks from the onset of stroke, and modified Rankin Scale (mRS) score at discharge. Overall, 192 patients were finally included and divided into three groups: Vit D sufficient (n = 28), insufficient (n = 49), and deficient (n = 115). Multivariate analysis showed that the Vit D deficient group presented with a higher risk of initially severe stroke (p = 0.025) and poor functional outcomes on the BBS (p = 0.048), MFT (p = 0.017), K-MMSE (p = 0.001), K-MBI (p = 0.003), and mRS (p = 0.032) compared to the Vit D sufficient group. Vit D deficiency may be associated with severe initial stroke and poor short-term post-stroke functional outcomes.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Deficiencia de Vitamina D , Humanos , Vitamina D , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular/complicaciones , Deficiencia de Vitamina D/complicaciones , Vitaminas
17.
Brain Sci ; 13(12)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38137133

RESUMEN

We developed an end-effector-type rehabilitation robot that can uses electro- and permanent magnets to generate a three-way magnetic field to assist hand movements and perform rehabilitation therapy. This study aimed to investigate the therapeutic effect of a rehabilitation program using a three-dimensional (3D) magnetic force-based hand rehabilitation robot on the motor function recovery of the paralyzed hands of patients with stroke. This was a double-blind randomized controlled trial in which 36 patients with subacute stroke were assigned to intervention and control groups of 18 patients each. The intervention group received 30 min of rehabilitation therapy per day for a month using a 3D magnetic force-driven hand rehabilitation robot, whereas the control group received 30 min of conventional occupational therapy to restore upper-limb function. The patients underwent three behavioral assessments at three time points: before starting treatment (T0), after 1 month of treatment (T1), and at the follow-up 1-month after treatment completion (T2). The primary outcome measure was the Wolf Motor Function Test (WMFT), and secondary outcome measures included the Fugl-Meyer Assessment of the Upper Limb (FMA_U), Modified Barthel Index (MBI), and European Quality of Life Five Dimensions (EQ-5D) questionnaire. No participant safety issues were reported during the intervention. Analysis using repeated measures analysis of variance showed significant interaction effects between time and group for both the WMFT score (p = 0.012) and time (p = 0.010). In post hoc analysis, the WMFT scores and time improved significantly more in the patients who received robotic rehabilitation at T1 than in the controls (p = 0.018 and p = 0.012). At T2, we also consistently found improvements in both the WMFT scores and times for the intervention group that were superior to those in the control group (p = 0.024 and p = 0.018, respectively). Similar results were observed for FMA_U, MBI, and EQ-5D. Rehabilitation using the 3D hand-rehabilitation robot effectively restored hand function in the patients with subacute stroke, contributing to improvement in daily independence and quality of life.

18.
Sci Rep ; 13(1): 22716, 2023 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-38123635

RESUMEN

The correlation between tonsil microbiome and tonsillar hypertrophy has not been well established. Given that oral dysbiosis is related to several metabolic diseases and that tonsillar hypertrophy leads to disordered breathing during sleep and obesity in children, it is necessary to investigate the relationship between the oral microbiome and tonsillar hypertrophy. After 16S rRNA amplicon sequencing of tonsillectomy samples, we evaluated the correlation between the tonsil microbiome and biochemical blood indices in pediatric patients who underwent tonsillectomy. Groups are classified into two categories: based on BMI, and grades 2, 3, and 4 based on tonsil size. Children with obesity and tonsillar hypertrophy have similar microbiome compositions and induce comparable changes in microbiome abundance and composition, confirming the association from a metagenomic perspective. In addition, obesity and tonsillar hypertrophy demonstrated a strong correlation with the Proteobacteria to Firmicutes (P/F) ratio, and among various biochemical indicators, alanine aminotransferase (ALT) levels increase with obesity and tonsillar hypertrophy, indicating a possible association of tonsil microbiome and liver metabolism. These novel findings demonstrate the significance of the tonsil microbiome and suggest the need for tonsil regulation, particularly during childhood.


Asunto(s)
Microbiota , Obesidad Infantil , Humanos , Niño , Tonsila Palatina , Obesidad Infantil/complicaciones , ARN Ribosómico 16S/genética , Hipertrofia/complicaciones
19.
Medicine (Baltimore) ; 102(43): e35847, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37904365

RESUMEN

Sarcopenia, a generalized loss of skeletal muscle mass that is primarily evident in the respiratory musculature, is associated with adverse outcomes in critically ill patients. However, the relationship between sarcopenia and ventilation-weaning outcomes has not yet been fully studied in patients with brain injuries. In this study, we examined the effect of reduced respiratory muscle mass on ventilation weaning in patients with brain injury. This observational study retrospectively reviewed the medical records of 73 patients with brain injury between January 2017 and December 2019. Thoracic skeletal muscle volumes were measured from thoracic CT images using the institute's three-dimensional modeling software program of our institute. The thoracic skeletal muscle volumes index (TSMVI) was normalized by dividing muscle volume by the square of patient height. Sarcopenia was defined as a TSMVI of less than the 50th sex-specific percentile. Among 73 patients with brain injury, 12 (16.5%) failed to wean from mechanical ventilation. The patients in the weaning-failure group had significantly higher sequential organ failure assessment scores [7.8 ±â€…2.7 vs 6.1 ±â€…2.2, P = .022] and lower thoracic skeletal muscle volume indexes [652.5 ±â€…252.4 vs 1000.4 ±â€…347.3, P = .002] compared with those in the weaning-success group. In multivariate analysis, sarcopenia was significantly associated with an increased risk of weaning failure (odds ratio 12.72, 95% confidence interval 2.87-70.48, P = .001). Our study showed a significant association between the TSMVI and ventilation weaning outcomes in patients with brain injury.


Asunto(s)
Lesiones Encefálicas , Insuficiencia Respiratoria , Sarcopenia , Masculino , Femenino , Humanos , Desconexión del Ventilador/métodos , Estudios Retrospectivos , Sarcopenia/etiología , Sarcopenia/complicaciones , Respiración Artificial/efectos adversos , Músculo Esquelético/diagnóstico por imagen , Insuficiencia Respiratoria/etiología , Encéfalo , Lesiones Encefálicas/complicaciones
20.
Diagnostics (Basel) ; 13(18)2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37761273

RESUMEN

Background: Despite obtaining a good prognosis and long life expectancy, survivors of thyroid cancer can nevertheless develop subsequent primary cancer (SPC). We investigated the risk and types of SPC in patients with thyroid cancer and compared them with subjects without thyroid cancer history (controls). Methods: We conducted a nationwide, population-based, retrospective cohort study based on the Korean National Health Insurance Database. A total of 432,654 patients diagnosed with thyroid cancer between 2004 and 2019 were 1:1 matched with controls for age, sex, income, and region of residence. The hazard ratios (HR) and 95% confidence intervals (CI) of SPC were estimated using Cox proportional hazard models. Results: In total, 78,584 (18.2%) patients with thyroid cancer and 49,979 (11.6%) controls were diagnosed with SPCs over a mean follow-up of 6.9 years. Patients with thyroid cancer had a higher risk of SPC at any site (adjusted HR, 1.62; 95% CI, 1.60-1.64) than the controls. The risk of SPCs was particularly high for patients diagnosed with thyroid cancer at a younger age (<40 years) and within 5 years. Conclusions: Medical caregivers should consider the long-term follow-up of patients with thyroid cancer and discuss the risk of SPC, especially if they complain of cancer-related symptoms.

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