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1.
Clin Radiol ; 78(6): 437-443, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37028999

RESUMO

AIM: To develop a high-accuracy low-dose computed tomography (LDCT) lung nodule diagnosis system by combining artificial intelligence (AI) technology with the Lung CT Screening Reporting and Data System (Lung-RADS), which can be used in the future AI-aided diagnosis of pulmonary nodules. MATERIALS AND METHODS: The study comprised the following steps: (1) the best deep-learning segmentation method for pulmonary nodules was compared and selected objectively; (2) the Image Biomarker Standardization Initiative (IBSI) was used for feature extraction and to determine the best feature reduction method; and (3) a principal component analysis (PCA) and three machine learning methods were used to analyse the extracted features, and the best method was determined. The Lung Nodule Analysis 16 dataset was applied to train and test the established system in this study. RESULTS: The competition performance metric (CPM) score of the nodule segmentation reached 0.83, the accuracy of nodule classification was 92%, the kappa coefficient with the ground truth was 0.68, and the overall diagnostic accuracy (calculated by the nodules) was 0.75. CONCLUSION: This paper summarises a more efficient AI-assisted diagnosis process of pulmonary nodules, and has better performance compared with the previous literature. In addition, this method will be validated in a future external clinical study.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Inteligência Artificial , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Diagnóstico por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador
2.
Lett Appl Microbiol ; 62(1): 55-62, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26465801

RESUMO

UNLABELLED: An anaerobic kraft lignin (KL)-degrading bacterial strain was isolated from sludge of a pulp and paper mill. It was characterized as Acetoanaerobium sp. WJDL-Y2 by 16S rRNA gene sequencing. The maximum KL degradation capability of strain Y2 was determined to be 24·9% on a COD basis under an optimal condition with temperature of 31·5°C, initial pH of 6·8 and KL to nitrogen (as NH4 Cl) ratio of 6·5 by mass. Growth kinetic studies showed that the KL tolerance of strain Y2 was relatively high (Ki  = 8120·45 mg l(-1) ). Analysing KL degradation products by GC-MS revealed the formation of low-molecular-weight aromatic compounds (LMWACs), including benzene-propanoic acid, syringic acid and ferulic acid. This indicates that strain Y2 can oxidize lignin structure's p-hydroxyphenyl (H) units, guaiacyl (G) units and syringyl (S). In addition, the inoculated sample also contained low-molecular acid compounds, such as hexanoic acid, adipic acid and 2-hydroxybutyric acid, further validating strain Y2's ability to degrade KL. SIGNIFICANCE AND IMPACT OF THE STUDY: Kraft lignin containing effluents discharged from pulp and paper industries causes serious environmental pollution in developing countries. Due to the immense environmental adaptability and biochemical versatility, bacterial ligninolytic potential deserve to be studied for application in effluent treatment of pulp and paper industry. In this study, an anaerobic lignin-degrading bacterium, Acetoanaerobium sp. WJDL-Y2 (accession no. KF176997),was isolated from the sludge of a pulp and paper mill. Strain Y2 can play an important role in treating pulp and paper wastewater, as well as breaking down materials for biofuel and chemical production.


Assuntos
Biodegradação Ambiental , Resíduos Industriais , Lignina/metabolismo , Peptostreptococcus/isolamento & purificação , Peptostreptococcus/metabolismo , Esgotos/microbiologia , Adipatos/metabolismo , Caproatos/metabolismo , Ácidos Cumáricos/metabolismo , Ácido Gálico/análogos & derivados , Ácido Gálico/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hidroxibutiratos/metabolismo , Cinética , Dados de Sequência Molecular , Papel , RNA Ribossômico 16S/genética
3.
J Appl Microbiol ; 110(4): 871-80, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21241422

RESUMO

AIMS: To investigate the effect of medium compositions and culture conditions on keratinase production by a novel thermophilic fungus Myceliophthora thermophila (Apinis) Oorschot strain GZUIFR-H49-1. METHODS AND RESULTS: The thermophilic strain GZUIFR-H49-1 with keratinolytic ability was characterized and identified as a strain of M. thermophila on the basis of its morphological characters and molecular analysis of ITS1-5.8S-ITS2 rDNA sequence. Among the medium compositions tested, the soluble starch (SS), urea, sodium thiosulfate and CaCl2 were the most effective C-source, N-source, S-source and mineral ion, respectively, by employing the single-factor experiment. The urea and pH value were the significant factors (P < 0·05) for the keratinase production in this experiment condition using Plackett­Burman factorial design. The conditions of keratinase production were further optimized by Box­Behnken design. Consequently, there was a 6·4-fold increase (5100 U l−1) in the keratinase activity than the initial value (800 U l−1) by this optimal process. CONCLUSIONS: This study indicated that the optimization design proved a useful and powerful tool for the development of optimal medium compositions and culture conditions. Myceliophthora thermophila strain GZUIFR-H49-1 was a promising fungus strain for keratinase production.


Assuntos
Peptídeo Hidrolases/biossíntese , Sordariales/enzimologia , Meios de Cultura , Interpretação Estatística de Dados , Fermentação , Sordariales/classificação , Sordariales/citologia , Sordariales/isolamento & purificação
4.
Environ Geochem Health ; 26(2-3): 277-83, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15499784

RESUMO

Much attention is paid to soil health and environmental safety. Earthworms are an important indicator of soil ecosystem health and safety. Ecological toxicity of acetochlor and excessive urea, in both their single and joint effects, on earthworm Esisenia foelide was thus studied using the soil-culture method. Acetochlor had an enhanced toxicity from low concentration to high concentration. The mortality of earthworms after a 6-day exposure was changed from 0 to 86.7%, and the weight change rate ranged from 7.86 to -30.43%, when the concentration of acetochlor was increased from 164 to 730 mg kg(-1). Urea expressed its positive and beneficial effects on earthworms when its concentration was lower than 500 mg kg(-1). Strongly toxic effects took place when the concentration of urea was higher than 1000 mg kg(-1). The mortality of earthworms exposed to urea reached 100% when its concentration was more than 1500 mg kg(-1). When the concentration of urea was lower than 500 mg kg(-1), there were antagonistic effects between the two agrochemicals on earthworms; when the concentration of urea was higher than 500 mg kg(-1), joint toxic effects of acetochlor and excessive urea on earthworms were synergic. In any case, excessive urea application is very harmful to the health of soil ecosystems.


Assuntos
Herbicidas/toxicidade , Oligoquetos , Poluentes do Solo/toxicidade , Toluidinas/toxicidade , Animais , Interações Medicamentosas , Mortalidade , Dinâmica Populacional , Ureia/análise , Ureia/química
5.
Diagn Microbiol Infect Dis ; 40(3): 121-3, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11502380

RESUMO

A 56-year-old woman, with underlying rheumatic heart disease status post mitral valve replacement, presented with fever, low back pain radiating to right leg, and congestive heart failure. Magnetic resonance imaging detected an L5-S1 spinal epidural abscess. A vegetation on prosthetic mitral valve was found by transesophageal echocardiography. Cultures of epidural aspirate, surgical specimen, and blood all grew Candida albicans. She received surgical drainage of the spinal epidural abscess and i.v. amphotericin B 1 mg/kg/day for eight weeks. Clinical symptoms improved gradually and she was discharged without neurologic sequelae. She remained well and continued to lead an active life two years after discharge.


Assuntos
Candidíase/microbiologia , Endocardite/microbiologia , Abscesso Epidural/microbiologia , Próteses Valvulares Cardíacas/microbiologia , Vértebras Lombares/microbiologia , Anfotericina B/administração & dosagem , Anfotericina B/uso terapêutico , Candida albicans/isolamento & purificação , Candidíase/tratamento farmacológico , Candidíase/fisiopatologia , Candidíase/cirurgia , Endocardite/tratamento farmacológico , Endocardite/fisiopatologia , Endocardite/cirurgia , Abscesso Epidural/tratamento farmacológico , Abscesso Epidural/fisiopatologia , Abscesso Epidural/cirurgia , Feminino , Fluconazol/administração & dosagem , Fluconazol/uso terapêutico , Seguimentos , Humanos , Pessoa de Meia-Idade , Espondilolistese/tratamento farmacológico , Espondilolistese/microbiologia , Espondilolistese/fisiopatologia , Espondilolistese/cirurgia , Resultado do Tratamento
6.
Brain Res Brain Res Protoc ; 7(2): 121-30, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356378

RESUMO

With the advent of gene cloning and sequencing, it has become increasingly common to identify novel genes for which no antibody is available. The best approach to study the expression and the distribution of these new genes is by in situ hybridization. One of the challenges with this method is to define the exact cellular subtype where the gene of interest is expressed. Conventional isotopic in situ hybridization methods lack precision for cellular identification because radioactive probes often result in a scattered signal. To identify the exact cellular subtype expressing BM88, we established a rapid colocalization method using non-isotopic in situ hybridization followed by chromogenic immunohistochemistry on the same tissue section. We demonstrated that BM88, which was identified from subtractive hybridization experiments between normal and ischemic tolerant brain tissue, was expressed exclusively in neurons in normal adult rat brain. Paraffin-embedded tissue was used as it resulted in better preservation of tissue and cellular morphology, thus allowing for more accurate histological localization of gene expression. It also allowed for retrospective studies on a number of archived tissue samples.


Assuntos
Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/genética , Neurônios/química , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Elementos Antissenso (Genética) , Química Encefálica , Digoxigenina , Masculino , Proteínas de Membrana , Proteínas do Tecido Nervoso/imunologia , Inclusão em Parafina , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
7.
Bone ; 27(2): 209-18, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10913913

RESUMO

Osteoblast differentiation and function can be studied in situ in the metaphysis of growing long bones. Proliferation and apoptosis dominate in the primary spongiosa subjacent to the growth plate, and differentiation and function dominate in the proximal metaphysis. Apoptosis of osteocytes dominates at the termination of the trabeculae in diaphyseal marrow. As parathyroid hormone regulates all phases of osteoblast development, we studied the in vivo regulation by human parathyroid hormone (1-34) (PTH) of apoptosis in bone cells of the distal metaphysis of young male rats. Rats were given PTH at 80 microg/kg per day, once daily, for 1-28 days. Bone cells were defined for flow cytometry as PTH1-receptor-positive (PTH1R(+)) and growth factor-receptor-positive (GFR(+)) cells. Apoptotic cells stained positive for either TdT-mediated dUTP-X nick end labeling (TUNEL) or annexin V (annV(+)) were detected by either flow cytometry or immunohistochemistry. Apoptosis was also assessed at the tissue level by RNAse protection and caspase enzyme activity assays. PTH increased apoptotic osteoblasts in the proliferating zone and apoptotic osteocytes in the terminal trabecular zone, by 40%-60% within 2-6 days of PTH treatment, but values became equivalent to controls after 21-28 days of treatment. This transient increase was confirmed in PTH1R(+), GFR(+) bone cells isolated by flow cytometry. There was no detectable change in the steady-state mRNA levels of selected apoptotic genes. Starting at 3 days, at the tissue level, PTH inhibited activity of caspases, which recognize the DEVD peptide substrate (caspases 2, 3, and/or 7), but not those caspases recognizing LEHD or YVAD peptide sequences. We speculate that the localized and tissue level effects of PTH on apoptosis can be explained on the basis of its anabolic effect on bone. The transient increase in apoptosis in the proliferating zone and terminal trabecular zone may be the result of the increased activation frequency and bone turnover seen with daily PTH treatment. As once-daily PTH increases the number of differentiated osteoblasts, and as these and hematopoietic marrow cells dominate metaphyseal tissue, inhibition of caspase activity may contribute to their prolonged survival, enabling extension of trabecular bone into the diaphyseal marrow to increase bone mass.


Assuntos
Apoptose/efeitos dos fármacos , Fêmur/citologia , Osteócitos/citologia , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Fatores Etários , Animais , Anexina A5/análise , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Diáfises/citologia , Citometria de Fluxo , Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Osteócitos/química , Osteócitos/enzimologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Ratos Sprague-Dawley , Receptores Proteína Tirosina Quinases/análise , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Receptor IGF Tipo 1/análise , Receptores de Superfície Celular/análise , Receptores de Fatores de Crescimento de Fibroblastos/análise , Receptores de Hormônios Paratireóideos/análise , Receptores do Fator de Crescimento Derivado de Plaquetas/análise , Fator de Crescimento Transformador beta/análise , Receptor fas/genética
8.
J Formos Med Assoc ; 99(11): 873-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11155782

RESUMO

Focal lesions in the liver in patients with acquired immunodeficiency syndrome (AIDS) pose an important clinical problem. Hepatic smooth-muscle tumor is rare in AIDS patients and has been reported mostly in children. We describe a 32-year-old male AIDS patient, with previous disseminated tuberculosis, who developed a small tumor in the liver. Liver biopsy disclosed an unusual hepatic leiomyomatous neoplasm that was associated with Epstein Barr virus infection. It differed from the more common Kaposi's sarcoma and presented a relatively benign course.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4 , Leiomioma/complicações , Neoplasias Hepáticas/complicações , Infecções Oportunistas Relacionadas com a AIDS/complicações , Adulto , Humanos , Leiomioma/patologia , Leiomioma/virologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino
9.
Calcif Tissue Int ; 65(5): 369-73, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10541762

RESUMO

Intermittent administration of parathyroid hormone (PTH) increases trabecular bone mass in vivo by stimulating bone formation. To further characterize the cellular and molecular mediators of the anabolic response to PTH, we examined the effect of intermittent synthetic hPTH 1-34 on the expression and localization of selected early response genes, c-fos, c-jun, c-myc, and IL-6 protein, in bone tissue by immunohistochemistry. Young male Sprague-Dawley rats, 70-100 g, were injected s.c. with 8 microg/100 g PTH or vehicle control, once daily for 5 days. Femurs were harvested 1 and 24 hours after the fifth injection, then fixed, decalcified, processed for wax embedding, and sections were immunostained. Early response genes, c-fos, c-jun and IL-6, were strongly expressed in osteoblasts, osteocytes, and megakaryocytes in bones 1 hour after PTH, when compared with vehicle-treated controls or sections from rats, 24 hours after PTH injection. Osteoblasts, osteocytes, and megakaryocytes were also positive for c-myc but the differences in stain intensity between control and treated groups were marginal. Also, scattered islands of hematopoietic cells in the marrow stained intensely for IL-6 by 1 hour after PTH, but the stain intensity decreased to control level 24 hours after the last PTH injection. Scattered islands of hematopoietic cells in the bone marrow stained more strongly for c-fos than either c-jun or c-myc, but neither localization nor stain intensity were regulated by PTH at the time points examined. We conclude that during the immediate early phase of the anabolic response, PTH regulates c-fos, c-jun, and IL-6 expression in osteoblasts, osteocytes, megakaryocytes, and selected bone marrow hematopoietic cells in bone.


Assuntos
Osso e Ossos/efeitos dos fármacos , Genes Precoces/efeitos dos fármacos , Proteínas Imediatamente Precoces/metabolismo , Teriparatida/farmacologia , Administração Cutânea , Animais , Osso e Ossos/citologia , Humanos , Imuno-Histoquímica , Interleucina-6/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Ratos Sprague-Dawley , Teriparatida/administração & dosagem , Fatores de Tempo
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