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1.
BMC Musculoskelet Disord ; 24(1): 524, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37370076

RESUMO

BACKGROUND: In case of focal neuropathy, the muscle fibers innervated by the corresponding nerves are replaced with fat or fibrous tissue due to denervation, which results in increased echo intensity (EI) on ultrasonography. EI analysis can be conducted quantitatively using gray scale analysis. Mean value of pixel brightness of muscle image defined as EI. However, the accuracy achieved by using this parameter alone to differentiate between normal and abnormal muscles is limited. Recently, attempts have been made to increase the accuracy using artificial intelligence (AI) in the analysis of muscle ultrasound images. CTS is the most common disease among focal neuropathy. In this study, we aimed to verify the utility of AI assisted quantitative analysis of muscle ultrasound in CTS. METHODS: This is retrospective study that used data from adult who underwent ultrasonographic examination of hand muscles. The patient with CTS confirmed by electromyography and subjects without CTS were included. Ultrasound images of the unaffected hands of patients or subjects without CTS were used as controls. Ultrasonography was performed by one physician in same sonographic settings. Both conventional quantitative grayscale analysis and machine learning (ML) analysis were performed for comparison. RESULTS: A total of 47 hands with CTS and 27 control hands were analyzed. On conventional quantitative analysis, mean EI ratio (i.e. mean thenar EI/mean hypothenar EI ratio) were significantly higher in the patient group than in the control group, and the AUC was 0.76 in ROC analysis. In the analysis using machine learning, the AUC was the highest for the linear support vector classifier (AUC = 0.86). When recursive feature elimination was applied to the classifier, the AUC value improved to 0.89. CONCLUSION: This study showed a significant increase in diagnostic accuracy when AI was used for quantitative analysis of muscle ultrasonography. If an analysis protocol using machine learning can be established and mounted on an ultrasound machine, a noninvasive and non-time-consuming muscle ultrasound examination can be conducted as an ancillary tool for diagnosis.


Assuntos
Síndrome do Túnel Carpal , Adulto , Humanos , Síndrome do Túnel Carpal/diagnóstico por imagem , Nervo Mediano/diagnóstico por imagem , Estudos Retrospectivos , Inteligência Artificial , Estudos de Viabilidade , Ultrassonografia , Músculo Esquelético/diagnóstico por imagem
2.
J Neuroophthalmol ; 35(3): 284-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25993123

RESUMO

Scrub typhus is an acute febrile infectious disease caused by Orientia tsutsugamushi. The illness is usually characterized by fever, rash, and lymphadenopathy, but severe cases progress to pulmonary and neurological involvement. We report a 69-year-old man who developed ptosis and ophthalmoplegia with a focal nodular lesion in the anterior cavernous sinus detected with magnetic resonance imaging. Found to have scrub typhus, the ptosis and ophthalmoplegia resolved after treatment with doxycycline.


Assuntos
Oftalmoplegia/etiologia , Tifo por Ácaros/complicações , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética
3.
J Neural Transm (Vienna) ; 118(3): 433-44, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20924620

RESUMO

Anamorsin, also called cytokine-induced apoptosis inhibitor 1 (CIAPIN1), was recently identified to confer resistance to apoptosis induced by growth factor deprivation and to be indispensible for hematopoiesis. Recently, it was demonstrated that anamorsin is also widely distributed in both fetal and adult tissues. In this study, we evaluated the tissue distribution of anamorsin in the central nervous system (CNS) during development. In situ hybridization and immunoblot analyses revealed that anamorsin mRNA and protein were both highly and widely expressed in various regions of the CNS, including the cerebral cortex, hippocampus, midbrain, cerebellum, medulla, and spinal cord. Based on these findings, we examined its cellular localization during drug-induced neurodegeneration in MN9D dopaminergic cells. Both immunocytochemical localization and immunoblot analyses indicated that cytosolic anamorsin was translocated into the nucleus in a time-dependent manner following treatment with a reactive oxygen species (ROS)-inducing drug, 6-hydroxydopamine (6-OHDA). Treatment of cells with the apoptosis-inducing reagent, staurosporine, did not appear to cause translocation of anamorsin into the nucleus. When cells were treated with the nuclear export inhibitor, Leptomycin B, alone or with 6-OHDA, nuclear anamorsin levels increased, indicating that nuclear influx and efflux of anamorsin are regulated by 6-OHDA treatment. In rat brain injected with 6-OHDA, nuclear translocation of anamorsin was identified in certain tyrosine hydroxylase (TH)-positive neurons as well as TH-negative cells. Furthermore, treatment of MN9D cells with hydrogen peroxide or ROS-inducing trace metals caused nuclear translocation of anamorsin. Taken together, our data indicate that nuclear translocation of anamorsin is a ROS-dependent event and may participate in the regulation of transcription of critical molecules during dopaminergic neurodegeneration.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Dopamina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Degeneração Neural/metabolismo , Neurônios/metabolismo , Animais , Western Blotting , Fracionamento Celular , Células Cultivadas , Imuno-Histoquímica , Hibridização In Situ , Masculino , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia , Neurônios/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Estaurosporina/farmacologia
4.
Materials (Basel) ; 14(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206496

RESUMO

The reinforced concrete (RC) member's shear strength estimation has been experimentally studied in most cases due to its nonlinear behavior. Many empirical equations have been derived from the experimental data; however, even those adopted in the construction codes do not thoroughly and accurately describe their shear behavior. Theoretically explained equations, on the other hand, are aligned with the experiment; however, they are complicated to use in practice. As shear behavior research is data-driven, the machine learning technique is applicable. Herein, an artificial neural network (ANN) algorithm is trained with 776 experiment results collected from available publications. The raw data is preprocessed by principal component analysis (PCA) before the application of the ANN technique. The predictions of the trained algorithm using ANN with PCA are compared to those of formulae adopted in a few existing building codes. Finally, a parametric study is conducted, and the significance of each variable to the strength of RC members is analyzed.

5.
Appl Radiat Isot ; 59(4): 225-30, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14522229

RESUMO

We have developed an automated system for the preparation of highly concentrated 188Re-perrhenate, diethylenetriamine pentaacetic acid (DTPA) and mercaptoacetyltriglycine (MAG3). The three procedural steps include concentration of 188Re-perrhanerate, chelation and purification and sterilization. The steps are operated by a small micro-controller. The eluted 188Re-perrhenate of 15 GBq/18 ml from 37 GBq 188W/188Re-generator was concentrated to 1.2 ml in 10 +/- 0.5 min with a recovery yield of 95 +/- 1.5%. We obtained the highest radiochemical yield of 95.4 +/- 2.8% and 98.5 +/- 1.2% for 188Re-DTPA and MAG3 at the oil bath temperatures of 95-97 degrees C and 93-97 degrees C, respectively.


Assuntos
Glicina/análogos & derivados , Glicina/química , Marcação por Isótopo/instrumentação , Ácido Pentético/química , Radioisótopos/química , Compostos Radiofarmacêuticos/síntese química , Rênio/química , Robótica/instrumentação , Braquiterapia/instrumentação , Braquiterapia/métodos , Sistemas Computacionais , Metodologias Computacionais , Reestenose Coronária/prevenção & controle , Reestenose Coronária/radioterapia , Desenho de Equipamento , Análise de Falha de Equipamento , Glicina/síntese química , Glicina/isolamento & purificação , Humanos , Marcação por Isótopo/métodos , Ácido Pentético/síntese química , Ácido Pentético/isolamento & purificação , Radioisótopos/isolamento & purificação , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/isolamento & purificação , Rênio/isolamento & purificação , Robótica/métodos , Integração de Sistemas , Doenças Vasculares/prevenção & controle , Doenças Vasculares/radioterapia
6.
ISA Trans ; 41(1): 3-11, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12014800

RESUMO

In this paper, a vision-based inspection system that measures the dimensions of a ball stud is designed and implemented. The system acquires silhouetted images by backlighting and extracts the outlines of the nearly dichotomized images in subpixel accuracy. The sets of boundary data are modeled with reasonable geometric primitives and the parameters of the models are estimated in a manner that minimizes error. Jig-fixtures and servo systems for the inspection are also contrived. The system rotates an inspected object to recognize the objects in space not on a plane. The system moves the object vertically so that it may take several pictures of different parts of the object, resulting in improvement of measuring resolution. The performance of the system is evaluated by measurement of the dimensions of a standard ball, a standard cylinder, and a ball stud.


Assuntos
Sistemas Inteligentes , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Calibragem , Desenho de Equipamento , Estudos de Viabilidade
7.
Exp Neurobiol ; 23(1): 65-76, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24737941

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta. Most cases are sporadic and its etiology is incompletely understood. However, increasing evidence suggests that oxidative stress and mitochondrial dysfunction may be involved in the pathogenesis of Parkinson's disease. The aim of this study was to investigate changes in mitochondrial protein profiles during dopaminergic neuronal cell death using two-dimensional gel electrophoresis in conjunction with mass spectrometry. Several protein spots were found to be significantly altered following treatment of MN9D dopaminergic neuronal cells with 6-hydroxydopamine (6-OHDA). Among several identified candidates, TNF receptor-associated protein 1 (TRAP1), a mitochondrial molecular chaperone, was released from the mitochondria into the cytosol in MN9D cells as well as primary cultures of dopaminergic neurons following 6-OHDA treatment. This event was drug-specific in that such apoptotic inducers as staurosporine and etoposide did not cause translocation of TRAP1 into the cytosol. To our knowledge, the present study is the first to demonstrate the drug-induced subcellular translocation of TRAP1 during neurodegeneration. Further studies delineating cellular mechanism associated with this phenomenon and its functional consequence may provide better understanding of dopaminergic neurodegeneration that underlies PD pathogenesis.

8.
Arch Pathol Lab Med ; 133(8): 1278-84, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19653726

RESUMO

CONTEXT: The widespread use of the serum prostate-specific antigen test has increased the early detection of prostate cancer and consequently reduced grossly definable prostate cancers. OBJECTIVE: To find the most efficient gross sampling method for radical prostatectomy specimens not only preserving important prognostic factors but also being cost effective. DESIGN: We initially analyzed clinicopathologic features of the entire prostate sections from 148 radical prostatectomy specimens, which then were used to examine the impact of 5 partial sampling methods on tumor stage, Gleason score, extraprostatic extension, resection margin status, and paraffin block numbers. The methods included submission of (1) alternative slices, (2) alternative slices plus biopsy-positive posterior quarters, (3) every posterior half, (4) every posterior half plus one midanterior half, and (5) alternative slices plus peripheral 3-mm rim of the remaining prostate. RESULTS: Prostate cancers and their extraprostatic extension and resection margin involvement were commonly located in the right posterior portion of the prostate. Method 5 was most efficient, detecting all cases with extraprostatic extension and resection margin involvement and reducing 25% of paraffin blocks compared with the entire sampling of the prostate. The Gleason scores were retained in most of cases, except reversal of the primary and secondary Gleason grade component in only 2 cases (1%). Only 4 cases (3%) were downstaged within the same T2 stage. CONCLUSIONS: These results demonstrate that sampling of alternative slices plus peripheral rim of the remaining prostate is the most efficient partial sampling method for radical prostatectomy specimens.


Assuntos
Adenocarcinoma/diagnóstico , Detecção Precoce de Câncer , Prostatectomia , Neoplasias da Próstata/diagnóstico , Manejo de Espécimes/métodos , Adenocarcinoma/sangue , Adenocarcinoma/cirurgia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia , Tamanho da Amostra
9.
J Biol Chem ; 283(15): 9986-98, 2008 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-18250162

RESUMO

The aim of this study was to investigate changes in protein profiles during the early phase of dopaminergic neuronal death using two-dimensional gel electrophoresis in conjunction with mass spectrometry. Several protein spots were identified whose expression was significantly altered following treatment of MN9D dopaminergic neuronal cells with 6-hydroxydopamine (6-OHDA). In particular, we detected oxidative modification of thioredoxin-dependent peroxidases (peroxiredoxins; PRX) in treated MN9D cells. Oxidative modification of PRX induced by 6-OHDA was blocked in the presence of N-acetylcysteine, suggesting that reactive oxygen species (ROS) generated by 6-OHDA induce oxidation of PRX. These findings were confirmed in primary cultures of mesencephalic neurons and in rat brain injected stereotaxically. Overexpression of PRX1 in MN9D cells (MN9D/PRX1) exerted neuroprotective effects against death induced by 6-OHDA through scavenging of ROS. Consequently, generation of both superoxide anion and hydrogen peroxide following 6-OHDA treatment was decreased in MN9D/PRX1. Furthermore, overexpression of PRX1 protected cells against 6-OHDA-induced activation of p38 MAPK and subsequent activation of caspase-3. In contrast, 6-OHDA-induced apoptotic death signals were enhanced by RNA interference-targeted reduction of PRX1 in MN9D cells. Taken together, our data suggest that the redox state of PRX may be intimately involved in 6-OHDA-induced dopaminergic neuronal cell death and also provide a molecular mechanism by which PRX1 exerts a protective role in experimental models of Parkinson disease.


Assuntos
Adrenérgicos/toxicidade , Apoptose/efeitos dos fármacos , Mesencéfalo/metabolismo , Oxidopamina/toxicidade , Doença de Parkinson Secundária/metabolismo , Peroxirredoxinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Acetilcisteína/farmacologia , Animais , Caspase 3/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Neurônios/metabolismo , Oxirredução/efeitos dos fármacos , Doença de Parkinson Secundária/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Appl Opt ; 44(35): 7522-31, 2005 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-16363776

RESUMO

The mode spectrum in an optical nanowaveguide consisting of a dielectric-core layer surrounded by two identical metal layers is investigated. A simple model based on mode matching to predict the properties of mode propagation in such optical nanowaveguides is proposed. It is shown that quasi-TM00 and quasi-TM10 modes supported by an optical microstrip line do not have a cutoff frequency, regardless of the size of the metal strips, the thickness of the dielectric slab, and the cross-sectional shape. The transverse size of the TM00 mode supported by a nanosized microstrip line was found to be approximately equal to the transverse dimension of the microstrip line. In closed rectangular and elliptical nanowaveguides, i.e., in which all dielectric surfaces are covered with metal films, the cross-sectional shape of the waveguide should be stretched along one side to produce propagation conditions for the fundamental mode.


Assuntos
Desenho Assistido por Computador , Metais/química , Microscopia Confocal/instrumentação , Modelos Teóricos , Nanotecnologia/instrumentação , Óptica e Fotônica/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Microscopia Confocal/métodos , Nanotecnologia/métodos , Espalhamento de Radiação
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