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1.
Sensors (Basel) ; 23(4)2023 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-36850668

RESUMEN

It is a continual and challenging problem to detect small defects in metallic structures for array eddy current testing (ECT) probes, which require the probe to have ultra-high resolution and sensitivity. However, the spatial resolution of an ECT array probe is limited by the size of the induction coils. Even if it is possible to increase the spatial resolution by using smaller coils, the sensitivity of the sensor also decreases. To obtain finer spatial resolution without sacrificing sensitivity, this paper proposes a resolution enhanced ECT array probe with four rows of coils attached to a flexible printed circuit board (FPCB). The distance between each two adjacent coils in a row is 2 mm and the position of each row is offset by 0.5 mm along the horizontal direction related to its prior row. The outputs of the four rows are aligned and interpolated in a line, and in this way the image resolution of the probe is increased to 0.5 mm. The probe is configured to operate with the differential setting, namely two differential coils operate simultaneously at each time. The currents in the two coils can be controlled to have the same flowing direction or opposite flowing direction, resulting in different distributions of the induced eddy current and two sets of output images. A patch-image model and an image fusion method based on discrete wavelet transforms are employed to suppress the noise and highlight the defects' indications. Experimental results show that small defects with dimensions as small as length × width × depth = 1 mm × 0.1 mm × 0.3 mm on a 304 stainless-steel sample can be detected from the fused image, demonstrating that the probe has super sensitivity for small defects inspection.

2.
Exp Cell Res ; 402(2): 112574, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33794264

RESUMEN

Congenital anorectal malformations (ARMs) are among the most prominent deformities of the gastrointestinal tract; however, their precise aetiology remains obscure. Immunohistochemistry demonstrated that, in the ARM group, the PPPDE1-positive cells were widely distributed in the hindgut epithelial tissue from GD13 to GD16. Immunofluorescence revealed that most TUNEL-, Bax-, and Cytochrome C (Cyt C)-positive cells overlapped with PPPDE1-positive cells in the urorectal septum (URS). Western blotting and quantitative real-time RT-PCR revealed that PPPDE1 levels were significantly higher in the ARM group from GD13 to GD14 (p < 0.05). IEC-6 cells were transfected with PPPDE1 overexpression plasmid/NC (negative control) or si-PPPDE1/si-NC. Flow cytometry analysis and CCK-8 assay (used to detect apoptosis and proliferation, respectively), as well as western blotting, showed that the levels of PPPDE1 were positively correlated with the pro-apoptotic molecules Bax and Cyt C. Accordingly, aberrantly high expression of PPPDE1 caused a spatiotemporal imbalance in foetal rats with ARMs during hindgut development. Therefore, the upregulation of PPPDE1 may promote epithelial apoptosis and reduce proliferation in the hindgut via the mitochondrial apoptotic pathway. This could affect the fusion of the URS and cloacal membrane, ultimately inhibiting the hindgut development and resulting in ARMs.


Asunto(s)
Malformaciones Anorrectales/genética , Liasas de Carbono-Nitrógeno/genética , Tracto Gastrointestinal/metabolismo , Proteína X Asociada a bcl-2/genética , Animales , Malformaciones Anorrectales/patología , Apoptosis/genética , Proliferación Celular/genética , Citocromos c/genética , Embrión de Mamíferos , Desarrollo Fetal/genética , Tracto Gastrointestinal/crecimiento & desarrollo , Tracto Gastrointestinal/patología , Humanos , Mitocondrias/genética , Ratas , Transducción de Señal/genética , Activación Transcripcional/genética
3.
J Obstet Gynaecol Res ; 46(6): 939-944, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32342628

RESUMEN

Colposcopy is a visual technique to examine the cervix and determine selection of sites for biopsies and eligibility for treatment. It's always been a critical part of identifying preinvasive and early invasive cervical carcinoma. Unfortunately, challenges exist with regards to the accuracy of traditional colposcopy. Hence, to fully exploit the benefit of increasing diagnostic sensitivity, there is a pressing need to improve the performance of colposcopy by applying novel innovations and techniques. In this case report, we used a recently developed, high-resolution multispectral endoscopy and evaluated its performance by comparing colposcopic image features (the vascular pattern, in particular, depending upon the improved optics and illumination) with histology results. High-resolution multispectral endoscopy makes it easier to distinguish the features of pathological vessels, so that it has a higher sensitivity and specificity to detect cervical lesions, especially in discriminating the vascular pattern using multispectral technology.


Asunto(s)
Endoscopía/métodos , Displasia del Cuello del Útero/diagnóstico , Adulto , Colposcopía/normas , Femenino , Humanos , Persona de Mediana Edad , Sensibilidad y Especificidad , Displasia del Cuello del Útero/patología
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(11): 1233-1239, 2020 Nov.
Artículo en Zh | MEDLINE | ID: mdl-33172561

RESUMEN

OBJECTIVE: To study the effect of mogroside VI (MVI) on acute liver injury induced by sepsis in mice and its possible mechanisms. Methods A total of 60 male C57BL/6 mice were randomly divided into five groups: sham-operation, model, low-dose MVI (25 mg/kg), high-dose MVI (100 mg/kg), peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) inhibitor (100 mg/kg MVI+30 mg/kg PGC-1α inhibitor SR-18292), with 12 mice in each group. Cecal ligation and puncture were performed to establish a mouse model of sepsis. The drugs were given by intraperitoneal injection after the model was established, once a day for 3 consecutive days. ELISA was used to measure the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Colorimetry was used to measure the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in liver tissue. Hematoxylin-eosin staining was used to observe liver histopathological changes. Liver mitochondrial respiratory function was measured, and mitochondrial respiratory control rate was calculated. RT-PCR was used to measure the copy number of mitochondrial DNA (mtDNA) in liver tissue and the mRNA expression levels of PGC-1α, nuclear respiratory factor-1 (NRF-1), and mitochondrial transcription factor A (TFAM) in liver tissue. Western blot was used to measure the protein expression levels of PGC-1α, NRF-1, and TFAM in liver tissue. RESULTS: Compared with the sham-operation group, the model group had significant increases in the serum levels of ALT and AST and the content of MDA in liver tissue (P<0.05) and significant reductions in the activities of GSH-Px and SOD in liver tissue (P<0.05). The model group had also severe liver histopathological injury and significant reductions in the mitochondrial respiratory control rate, the copy number of mtDNA, and the mRNA and protein expression levels of PGC-1α, NRF-1, and TFAM in liver tissue (P<0.05). Compared with the model group, the high-dose group had significant reductions in the serum levels of ALT and AST and the content of MDA in liver tissue (P<0.05), significant increases in the activities of GSH-Px and SOD in liver tissue (P<0.05), significant improvement in liver histopathological injury, and significant increases in the mitochondrial respiratory control rate, the copy number of mtDNA, and the mRNA and protein expression levels of PGC-1α, NRF-1, and TFAM in liver tissue (P<0.05). There were no significant differences in the above indicators between the low-dose and model groups (P>0.05). The PGC-1α inhibitor SR-18292 significantly inhibited the intervention effect of high-dose MVI (P<0.05). CONCLUSIONS: MVI can effectively alleviate acute liver injury caused by sepsis in mice, possibly by enhancing mitochondrial biosynthesis mediated by PGC-1α.


Asunto(s)
Sepsis , Triterpenos , Animales , Hígado , Masculino , Ratones , Ratones Endogámicos C57BL , Sepsis/tratamiento farmacológico
5.
Cell Mol Biol (Noisy-le-grand) ; 64(7): 43-50, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29974845

RESUMEN

Abnormal proliferation of vascular smooth muscle cells (VSMCs) induced by high cyclic stretch is crucial in the vascular remodeling during hypertension. Vascular endothelial growth factor A (VEGFA) alternative splicing plays important roles in the pathological process of vascular diseases and remodeling. However, the roles of VEGFA isoforms in modulating VSMC functions in response to cyclic stretch remain unclear. We hypothesize that high cyclic stretch may induce VEGFA alternative splicing via Serine/arginine-rich splicing factor 1 (SRSF1) which subsequently induce VSMC proliferation. In the present research, hypertensive rat model was established using the abdominal aortic constriction method. In comparison with sham-operated group, immunohistology staining showed translocation of SRSF1 into nuclei in hypertensive rat thoracic aorta, and RT-PCR detected a shift of VEGFA expression pattern, including the increased expression of VEGFA120 and VEGFA164, but not VEGFA188.Then VSMCs were subjected to cyclic stretch in vitro using a Flexercell strain unit. VEGFA ELISA assay showed 15% cyclic stretch increased the secretion of VEGFA which significantly increased proliferation of VSMCs. Western blot and immunofluorescence detected accumulation of SRSF1 in nuclei after 15% cyclic stretch application. Furthermore, SRSF1-specific siRNA transfection reversed the VEGFA secretion induced by pathological high cyclic stretch. Our present results suggested that pathologically high cyclic stretch induces the shuttling of SRSF1 which results in the secretive pattern splicing of VEGFA and finally contributes to the proliferation of VSMCs.


Asunto(s)
Empalme Alternativo , Hipertensión/patología , Músculo Liso Vascular/patología , Factores de Empalme Serina-Arginina/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Animales , Aorta Torácica/patología , Núcleo Celular/metabolismo , Proliferación Celular , Modelos Animales de Enfermedad , Humanos , Hipertensión/metabolismo , Masculino , Músculo Liso Vascular/metabolismo , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Factores de Empalme Serina-Arginina/genética , Vacio
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(7): 559-562, 2018 Jul.
Artículo en Zh | MEDLINE | ID: mdl-30022758

RESUMEN

OBJECTIVE: To study the clinical value of red blood cell distribution width (RDW) in the early prediction of acute kidney injury (AKI) in children with sepsis. METHODS: A total of 126 children with sepsis were divided into an AKI group (n=66) and a non-AKI group (n=60) according to the presence or absence of AKI. These patients were also classified into high-RDW and low-RDW groups according to the mean RDW. The groups were compared in terms of age, male-to-female ratio, body mass index (BMI), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, Sequential Organ Failure Assessment (SOFA) score, serum blood urea nitrogen (BUN), creatinine (Cr), uric acid (UA), serum C-reactive protein (CRP), and routine blood test results. Independent factors associated with RDW were analyzed by multiple linear regression. RESULTS: Age, male-to-female ratio, BMI, CRP, SOFA score, and APACHE II score did not differ significantly between the AKI and non-AKI groups (P>0.05), but the AKI group had significantly higher BUN, Cr, UA, and RDW levels than the non-AKI group (P<0.05). Age, male-to-female ratio, and BMI did not differ significantly between the high-RDW and low-RDW groups (P>0.05), but the high-RDW group had significantly higher BUN, Cr, UA, CRP, SOFA score, APACHE II score, Hb, and mean corpuscular volume (MCV) than the low-RDW group (P<0.05). The multiple linear regression analysis showed that age, sex, APACHE II score, Cr, Hb, and MCV were independent factors associated with RDW. CONCLUSIONS: RDW has a certain clinical value in the early prediction of AKI in children with sepsis.


Asunto(s)
Lesión Renal Aguda/sangre , Eritrocitos/citología , Sepsis/sangre , APACHE , Lesión Renal Aguda/diagnóstico , Adolescente , Niño , Preescolar , Creatinina/sangre , Índices de Eritrocitos , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Sepsis/diagnóstico
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(9): 919-21, 2014 Sep.
Artículo en Zh | MEDLINE | ID: mdl-25229960

RESUMEN

OBJECTIVE: To evaluate the value of high mobility group box 1(HMGB1) in the diagnosis of pediatric acute appendicitis. METHODS: The children with acute abdomen who had a diagnosis of suspected acute appendicitis between January and July 2013 and 25 healthy children were enrolled in this study. Serum HMGB1 levels were measured using ELISA on admission. The patients were classified into 2 groups according to surgery confirmation or pathological results: appendicitis (n=28) and non-appendicitis (n=35). RESULTS: Serum HMGB1 levels and WBC in the appendicitis and non-appendicitis groups were significantly higher than in the healthy children group (P<0.01). The appendicitis group showed more increased serum HMGB1 levels compared with the non-appendicitis group (median: 32.9 ng/mL vs 22.0 ng/mL; P<0.01). For a diagnosis of acute appendicitis, the sensitivity and specificity of serum HMGB1 was 71.4% and 82.9% respectively at the best cutoff of 28.0 ng/mL, with the accuracy of 77.8% and the area under the curve of 0.765 (95%CI 0.638-0.893). CONCLUSIONS: HMGB1 may play a role in the diagnosis of pediatric acute appendicitis.


Asunto(s)
Apendicitis/diagnóstico , Proteína HMGB1/sangre , Enfermedad Aguda , Apendicitis/sangre , Preescolar , Femenino , Humanos , Lactante , Masculino
8.
JMIR Med Educ ; 10: e49970, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227351

RESUMEN

BACKGROUND: ChatGPT is among the most popular large language models (LLMs), exhibiting proficiency in various standardized tests, including multiple-choice medical board examinations. However, its performance on otolaryngology-head and neck surgery (OHNS) certification examinations and open-ended medical board certification examinations has not been reported. OBJECTIVE: We aimed to evaluate the performance of ChatGPT on OHNS board examinations and propose a novel method to assess an AI model's performance on open-ended medical board examination questions. METHODS: Twenty-one open-ended questions were adopted from the Royal College of Physicians and Surgeons of Canada's sample examination to query ChatGPT on April 11, 2023, with and without prompts. A new model, named Concordance, Validity, Safety, Competency (CVSC), was developed to evaluate its performance. RESULTS: In an open-ended question assessment, ChatGPT achieved a passing mark (an average of 75% across 3 trials) in the attempts and demonstrated higher accuracy with prompts. The model demonstrated high concordance (92.06%) and satisfactory validity. While demonstrating considerable consistency in regenerating answers, it often provided only partially correct responses. Notably, concerning features such as hallucinations and self-conflicting answers were observed. CONCLUSIONS: ChatGPT achieved a passing score in the sample examination and demonstrated the potential to pass the OHNS certification examination of the Royal College of Physicians and Surgeons of Canada. Some concerns remain due to its hallucinations, which could pose risks to patient safety. Further adjustments are necessary to yield safer and more accurate answers for clinical implementation.


Asunto(s)
Otolaringología , Cirujanos , Humanos , Canadá , Certificación , Alucinaciones
9.
Int J Biol Macromol ; 273(Pt 1): 133075, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38866274

RESUMEN

Hemostatic materials play a crucial role in trauma medicine. However, existing materials have poor hemostatic efficacy and a tendency to adhere to the wound surface, limiting their clinical effectiveness. Herein, a drug-loaded, superhydrophilic/superhydrophobic laminated material (DSLM), consisting of a superhydrophobic inner layer with a micropore array, a superhydrophilic chitosan-based sponge layer loaded with hemostatic/antimicrobial drugs, and a superhydrophobic outer layer, was developed. Furthermore, the DSLM allows unidirectional flow of blood and exudates from the wound bed through the superhydrophobic inner layer while facilitating efficient drug delivery. In addition, it possesses excellent biocompatibility and antiadhesion properties, as confirmed by in vivo and in vitro experiments. Compared with traditional hemostatic materials, the DSLM remarkably increased the survival time by over threefold in the acute femoral transaction wound bleeding model, and simultaneously prevented secondary wound damage by reducing peeling force to one-eighth incomparison to pristine gauze. The DSLM holds promise as a versatile clinical biomaterial for prehospital acute trauma treatment, with its simple structure facilitating manufacturing and expanding applications in biomedicine.


Asunto(s)
Quitosano , Hemostasis , Hemostáticos , Interacciones Hidrofóbicas e Hidrofílicas , Quitosano/química , Hemostasis/efectos de los fármacos , Animales , Hemostáticos/química , Hemostáticos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Hemorragia/tratamiento farmacológico , Hemorragia/prevención & control , Ratas , Ratones , Cicatrización de Heridas/efectos de los fármacos , Masculino , Humanos
10.
Artículo en Inglés | MEDLINE | ID: mdl-38895862

RESUMEN

OBJECTIVE: The recent surge in popularity of large language models (LLMs), such as ChatGPT, has showcased their proficiency in medical examinations and potential applications in health care. However, LLMs possess inherent limitations, including inconsistent accuracy, specific prompting requirements, and the risk of generating harmful hallucinations. A domain-specific model might address these limitations effectively. STUDY DESIGN: Developmental design. SETTING: Virtual. METHODS: Otolaryngology-head and neck surgery (OHNS) relevant data were systematically gathered from open-access Internet sources and indexed into a knowledge database. We leveraged Retrieval-Augmented Language Modeling to recall this information and utilized it for pretraining, which was then integrated into ChatGPT4.0, creating an OHNS-specific knowledge question & answer platform known as ChatENT. The model is further tested on different types of questions. RESULTS: ChatENT showed enhanced performance in the analysis and interpretation of OHNS information, outperforming ChatGPT4.0 in both the Canadian Royal College OHNS sample examination questions challenge and the US board practice questions challenge, with a 58.4% and 26.0% error reduction, respectively. ChatENT generated fewer hallucinations and demonstrated greater consistency. CONCLUSION: To the best of our knowledge, ChatENT is the first specialty-specific knowledge retrieval artificial intelligence in the medical field that utilizes the latest LLM. It appears to have considerable promise in areas such as medical education, patient education, and clinical decision support. The model has demonstrated the capacity to overcome the limitations of existing LLMs, thereby signaling a future of more precise, safe, and user-friendly applications in the realm of OHNS and other medical fields.

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