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1.
STAR Protoc ; 4(4): 102553, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37729057

RESUMO

In vitro embryonic analogue models, such as gastruloids, trunk-like structures and embryoids, have been developed to understand principles of early development and morphogenesis. However, models that can fully mimic head formation are still missing. Here, we present a protocol for generating the head-like structure (HLS) in zebrafish embryonic explants. We describe steps for dissection and constructing cell and patterning landscapes. We then detail assessment of this structure through axis induction. For complete details on the use and execution of this protocol, please refer to Cheng et al. (2023).1.


Assuntos
Dissecação , Peixe-Zebra , Animais , Morfogênese
2.
Huan Jing Ke Xue ; 43(8): 3923-3933, 2022 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-35971691

RESUMO

In order to study the characteristics of atmospheric dry and wet deposition elements and the health risks of typical industrial and mining cities in central Yunnan, the atmospheric dry and wet depositions collected from June 2019 to July 2020 in Anning city were selected as the research object and measured. The contents of the 11 indexes TN, F, Cr, Ni, Cu, Zn, Cd, Pb, P, As, and Hg were determined, the annual atmospheric deposition flux was calculated, and the exposure risk model was used to assess the risk to human health. The results showed that:1 In addition to Cr, Ni, and As in the atmospheric dry sediments, the average contents of the elements F, Cu, Zn, Cd, Pb, and Hg were significantly higher than those of the surface soil in Anning City, which were 5.82, 3.00, 28.27, 57.53, 2.83, and 1.08 times higher, respectively. The average contents of F and total nitrogen in wet deposition exceeded the standard value of surface water V-class water. 2 The annual atmospheric deposition flux of total nitrogen was the highest, and the annual deposition flux of eight heavy metal elements from smallest to largest was Hg

Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Adulto , Cádmio , Carcinógenos , Criança , China , Cidades , Monitoramento Ambiental/métodos , Humanos , Chumbo , Metais Pesados/análise , Nitrogênio , Medição de Risco , Solo/química , Poluentes do Solo/análise , Água
3.
World J Clin Cases ; 10(15): 4843-4855, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35801039

RESUMO

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a severe and long-lasting side effect caused by various anticancer agents that damage sensory, motor and autonomic nerves. It can cause maladaptive behaviors, including disease severity, anxiety, depression, sleep disorders, falls, and social impairment. These disorders have physical, psychological and social effects on patients and can seriously influence their quality of life. AIM: To investigate the current situation of psychosocial adaptation to the disease and its influencing factor in patients with CIPN. METHODS: A convenience sampling method was used to select 233 patients with CIPN in our hospital from February to August 2021. In addition, a cross-sectional survey was conducted using a sociodemographic questionnaire, the Self-Report Psychosocial Adjustment to Illness Scale, and the European Organisation for the Research and Treatment of Cancer Quality of Life CIPN20 (QLQ-CIPN20). Factors influencing psychosocial adaptation in patients with CIPN were analyzed by t-test or one-way analysis of variance, correlation analysis, multiple stepwise regression analysis, and structural equation models. RESULTS: The psychosocial adaptation score of patients with CIPN was 52.51 ± 13.18. Multivariate analysis showed that autonomic nerves, tumor stage, motor nerves, education level, availability of caregivers, semi-retirement status, CIPN grade were independent risk factors for patients with CIPN (P < 0.05). Structural equation models showed that QLQ-CIPN20 mediated the relationship between CIPN grade, tumor stage, and psychosocial adaptation. CONCLUSION: Patients with CIPN have poor psychosocial adaptation and are affected by a variety of physiological, psychological, and social factors. Patients' adaptive responses should be assessed, and targeted interventions implemented.

4.
Opt Lett ; 46(16): 4009-4012, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388798

RESUMO

In this Letter, we report a study on the effects of spatial filtering for a transmission Mueller matrix imaging system. A spatial filter (SF) is placed on the back Fourier plane of the imaging lens in a dual-rotating-retarders Mueller matrix imaging system to select photons within a certain scattering angle. The system is then applied to three types of human cancerous tissues. When imaging with a small-aperture SF, some polarimetry basis parameters show sharp changes in contrast in the cancerous regions. Monte Carlo simulations using a simple sphere-cylinder scattering model also show that spatial filtering of the scattered photons provides extra information on the size and shape of the scattering particles. The results indicate that spatial filtering enhances the capability of polarization imaging as a powerful tool for biomedical diagnosis.


Assuntos
Neoplasias , Fótons , Diagnóstico por Imagem , Humanos , Microscopia de Polarização , Método de Monte Carlo
5.
Korean J Radiol ; 22(3): 425-434, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33236543

RESUMO

OBJECTIVE: To investigate the potential value of 18F-fluorodeoxyglucose (FDG) PET/CT in predicting the survival of patients with primary tracheal malignant tumors. MATERIALS AND METHODS: An analysis of FDG PET/CT findings in 37 primary tracheal malignant tumor patients with a median follow-up period of 43.2 months (range, 10.8-143.2 months) was performed. Cox proportional hazards regression analyses were used to assess the associations between quantitative 18F-FDG PET/CT parameters, other clinic-pathological factors, and overall survival (OS). A risk prognosis model was established according to the independent prognostic factors identified on multivariate analysis. A survival curve determined by the Kaplan-Meier method was used to assess whether the prognosis prediction model could effectively stratify patients with different risks factors. RESULTS: The median survival time of the 37 patients with tracheal tumors was 38.0 months, with a 95% confidence interval of 10.8 to 65.2 months. The 3-year, 5-year and 10-year survival rate were 54.1%, 43.2%, and 16.2%, respectively. The metabolic tumor volume (MTV), total lesion glycolysis (TLG), maximum standardized uptake value, age, pathological type, extension categories, and lymph node stage were included in multivariate analyses. Multivariate analysis showed MTV (p = 0.011), TLG (p = 0.020), pathological type (p = 0.037), and extension categories (p = 0.038) were independent prognostic factors for OS. Additionally, assessment of the survival curve using the Kaplan-Meier method showed that our prognosis prediction model can effectively stratify patients with different risks factors (p < 0.001). CONCLUSION: This study shows that 18F-FDG PET/CT can predict the survival of patients with primary tracheal malignant tumors. Patients with an MTV > 5.19, a TLG > 16.94 on PET/CT scans, squamous cell carcinoma, and non-E1 were more likely to have a reduced OS.


Assuntos
Fluordesoxiglucose F18/química , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Traqueia/diagnóstico por imagem , Neoplasias da Traqueia/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Glicólise , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Traqueia/mortalidade , Neoplasias da Traqueia/patologia , Carga Tumoral , Adulto Jovem
6.
Pediatr Nephrol ; 35(11): 2163-2171, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32529322

RESUMO

BACKGROUND: In mainland China, dialysis for children with end-stage renal disease (ESRD) was not introduced until the 1980s. To describe the development of pediatric dialysis in different regions of China, a national pediatric dialysis network, namely, International Pediatric Dialysis Network-China (IPDN-China) ( www.pedpd.org.cn ), was launched in 2012. METHODS: Original and updated information from the renal centers registered with the IPDN-China was collected between 2012 and 2016 from two sources, namely, the registry and the survey, and demographic features were analyzed. RESULTS: Due to promotion by the IPDN-China, the number of registered renal centers increased from 12 to 39 between 2012 and 2016, with a significant increase in the coverage of the Chinese administrative divisions (from 26.5 to 67.6%) (p < 0.01); and the coverage of the pediatric (0~14 years old) population increased to nearly 90% in 2016. The distribution of renal centers indicated that East China had the highest average number of registered centers per million population (pmp) 0~14-year-old age group. Seventeen relatively large dialysis centers were distributed across 14 divisions. Various modalities of renal replacement therapy (RRT) were available in most centers. The IPDN-China has promoted collaborations between dieticians, psychologists, and social workers on dialysis teams to provide better service to children with ESRD and their families. The proportion of centers with all three types of paramedic support (i.e., dieticians, psychologists, and social workers) as well as the proportion of centers with a partial paramedic team significantly increased between 2012 (25.0%) and 2016 (69.2%) (p < 0.05). In terms of the point prevalent cases of patients (aged < 18 years), data from the survey of 39 registered centers revealed that the number of children with ESRD who were on RRT was 578 (49% received a kidney transplant) at the end of 2016, which was more than that reported in previous surveys. Data from the registry showed that 349 dialysis patients had been enrolled as of the end of 2016. The median age at RRT start was 9.5 years, and the leading cause of ESRD was congenital abnormalities of the kidney and urinary tract (CAKUT). CONCLUSIONS: The IPDN-China has helped to promote the development of pediatric dialysis for ESRD in China by improving the organization of care for dialysis patients and increasing the availability and the quality of RRT for patients who need it. To improve knowledge about the epidemiology and outcomes of pediatric RRT around the country, a sustained effort needs to be made by the IPDN-China to increase the enrollment of dialysis patients and increase the number of registered centers in the future.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Diálise Renal/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , China , Feminino , Acessibilidade aos Serviços de Saúde/organização & administração , Humanos , Lactente , Recém-Nascido , Masculino , Sistema de Registros
7.
J Biophotonics ; 11(4): e201700139, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29131523

RESUMO

Tissue-depolarization and linear-retardance are the main polarization characteristics of interest for bulk tissue characterization, and are normally interpreted from Mueller polarimetry. Stokes polarimetry can be conducted using simpler instrumentation and in a shorter time. Here, we use Stokes polarimetric imaging with circularly polarized illumination to assess the circular-depolarization and linear-retardance properties of tissue. Results obtained were compared with Mueller polarimetry in transmission and reflection geometry, respectively. It is found that circular-depolarization obtained from these 2 methods is very similar in both geometries, and that linear-retardance is highly quantitatively similar for transmission geometry and qualitatively similar for reflection geometry. The majority of tissue circular-depolarization and linear-retardance image information (represented by local image contrast features) obtained from Mueller polarimetry is well preserved from Stokes polarimetry in both geometries. These findings can be referred to for further understanding tissue Stokes polarimetric data, and for further application of Stokes polarimetry under the circumstances where short acquisition time or low optical system complexity is a priority, such as polarimetric endoscopy and microscopy.


Assuntos
Luz , Imagem Óptica , Fenômenos Ópticos , Animais , Mama/diagnóstico por imagem , Endoscopia , Humanos , Fígado/diagnóstico por imagem , Método de Monte Carlo , Suínos
8.
Sci Rep ; 7(1): 14702, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089638

RESUMO

Skin tissue consists of collagen and elastic fibres, which are highly susceptible to damage when exposed to ultraviolet radiation (UVR), leading to skin aging and cancer. However, a lack of non-invasive detection methods makes determining the degree of UVR damage to skin in real time difficult. As one of the fundamental features of light, polarization can be used to develop imaging techniques capable of providing structural information about tissues. In particular, Mueller matrix polarimetry is suitable for detecting changes in collagen and elastic fibres. Here, we demonstrate a novel, quantitative, non-contact and in situ technique based on Mueller matrix polarimetry for monitoring the microstructural changes of skin tissues during UVR-induced photo-damaging. We measured the Mueller matrices of nude mouse skin samples, then analysed the transformed parameters to characterise microstructural changes during the skin photo-damaging and self-repairing processes. Comparisons between samples with and without the application of a sunscreen showed that the Mueller matrix-derived parameters are potential indicators for fibrous microstructure in skin tissues. Histological examination and Monte Carlo simulations confirmed the relationship between the Mueller matrix parameters and changes to fibrous structures. This technique paves the way for non-contact evaluation of skin structure in cosmetics and dermatological health.


Assuntos
Diagnóstico por Imagem/métodos , Modelos Teóricos , Lesões Experimentais por Radiação/diagnóstico , Pele/metabolismo , Animais , Colágeno/metabolismo , Tecido Elástico/metabolismo , Humanos , Camundongos , Camundongos Nus , Microscopia de Polarização , Método de Monte Carlo , Pele/patologia , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos , Cicatrização
9.
Int J Mol Sci ; 17(8)2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27517919

RESUMO

Silk fibers suffer from microstructural changes due to various external environmental conditions including daily washings. In this paper, we take the backscattering Mueller matrix images of silk samples for non-destructive and real-time quantitative characterization of the wavelength-scale microstructure and examination of the effects of washing by different detergents. The 2D images of the 16 Mueller matrix elements are reduced to the frequency distribution histograms (FDHs) whose central moments reveal the dominant structural features of the silk fibers. A group of new parameters are also proposed to characterize the wavelength-scale microstructural changes of the silk samples during the washing processes. Monte Carlo (MC) simulations are carried out to better understand how the Mueller matrix parameters are related to the wavelength-scale microstructure of silk fibers. The good agreement between experiments and simulations indicates that the Mueller matrix polarimetry and FDH based parameters can be used to quantitatively detect the wavelength-scale microstructural features of silk fibers. Mueller matrix polarimetry may be used as a powerful tool for non-destructive and in situ characterization of the wavelength-scale microstructures of silk based materials.


Assuntos
Detergentes/química , Seda/química , Método de Monte Carlo
10.
J Pharm Biomed Anal ; 114: 447-54, 2015 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-26133103

RESUMO

A new method based on a Direct Analysis in Real Time (DART) ionization source coupled with triple quadrupole tandem mass spectrometry has been developed for rapid qualitative and quantitative analyses of 1-deoxynojirimycin (DNJ) in mulberry leaves. Two ions produced from DNJ, [M+H](+) (m/z 164) and [M-2H+H](+) (m/z 162), are observed using DART-MS in the positive ion mode. The peak areas of the two selected ions monitoring (SIM) signals of ([M+H](+) (m/z 164) and [M-2H+H](+) (m/z 162)) are integrated to determine the peak area for quantitative analyses. A reasonable linear regression equation is obtained in the range of 1.01 to 40.50 µg/mL, with a linear coefficient (R(2)) of 0.996. The limits of detection (LOD) and quantification (LOQ) of the method are 0.25 and 0.80 µg/mL, respectively. The range of recovery is shown to be 87.73-95.61%. The results derived from the developed DART-MS method are in good agreement with those from the conventional HPLC-FLD method. By contrast, DART-MS in SIM mode is a simple, rapid and high-throughput approach for the determination of the DNJ content in mulberry leaves. The present method is advantageous for the rapid screening of mulberry leaves containing high DNJ contents.


Assuntos
1-Desoxinojirimicina/análise , Espectrometria de Massas/métodos , Morus/química , Folhas de Planta/química , Clorofórmio/química , Cromatografia Líquida de Alta Pressão/métodos , Eletrodos , Etanol/química , Fluorenos/química , Íons , Limite de Detecção , Modelos Lineares , Nitrogênio/química , Reprodutibilidade dos Testes , Solventes/química , Espectrometria de Massas em Tandem , Temperatura
11.
Int J Pharm ; 476(1-2): 124-33, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25275938

RESUMO

In order to develop a skin tissue engineering material for wound dressing application, a novel gelatin-chitosan sponge scaffold was designed and studied. The effect of chitosan and gelatin ratio on the morphology, pore size, porosity, water uptake capacity, water retention capacity and the degradation behavior were evaluated. Biocompatibility was investigated by both MTT method and AO/EB staining method. Antibacterial assessment and in vivo pharmacodynamic was also studied to evaluate the potential for wound healing. Results showed the sponge scaffold have uniform porous structure with pore size range between 120 and 140 µm, high porosity (>90%), high water uptake capacity (>1500%), high water retention capacity (>400%), and degradation percent in 28 days between 38.3 and 53.9%. Biocompatibility results showed that the activity of cells could not be affected by the nature of the sponge and it was suitable for cell adhesion and proliferation for 21 days. In vivo evaluation indicated that the sponge scaffold could offer effective support and attachment to cells for skin wound healing. In conclusion, the developed sponge scaffold was a potential skin tissue engineering material with appropriate physical properties and good biocompatibility.


Assuntos
Quitosana/química , Gelatina/química , Engenharia Tecidual , Alicerces Teciduais , Animais , Materiais Biocompatíveis/química , Adesão Celular/fisiologia , Linhagem Celular , Proliferação de Células/fisiologia , Humanos , Masculino , Porosidade , Coelhos , Pele/metabolismo , Fatores de Tempo , Água/metabolismo , Cicatrização/fisiologia
12.
Chin Med J (Engl) ; 127(2): 232-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24438609

RESUMO

BACKGROUND: Spine is the most common site of bone metastases in patients with cancer. Conventional external beam radiotherapy lacks precision to allow delivery of large fraction radiation but simultaneously limit the dose to spinal cord. The purpose of this study was to evaluate the safety and efficacy of CyberKnife(®) radiation therapy for spinal metastases. METHODS: Seventy-three lesions in 62 patients treated with CyberKnife radiotherapy from September 2006 to June 2010 for spinal metastases were retrospectively reviewed. Thirteen tumors in 12 patients had received prior radiation. Patients were followed clinically and radiographically for at least 12 months or until death. In all patients, the spinal cord and thecal sac were contoured for dose-volume constraints, and maximum doses to 0.1, 0.5, 1, 2, and 5-ml volumes were analyzed. RESULTS: Using the CyberKnife System, 20-48 Gy in one to five fractions for unirradiated patients, and 21-38 Gy in one to five fractions for the previously irradiatied patients, were delivered. Median 2-Gy normalized Biological Equvalent Dose (nBED) of unirradiated targets and irradiated targets were 49.6 Gy10/2 (range, 31.25-74.8 Gy10/2) and 46.9 Gy10/2 (range, 29.8-66 Gy10/2), respectively. With a median follow-up of 9.4 months (range, 2.5-45 months), twenty-nine patients (46.7%) were alive, whereas the others died of progressive disease. Fifty-six patients (93.3%) reported complete or partial reduction of pain after CyberKnife radiotherapy at one-month follow-up, 17 patients (28.3%) reported some degree of pain relief after first fraction of the treatment course. Two patients experienced local recurrence at fifth and ninth months post-radiotherapy. Median maximum nBED for spinal cord and thecal sac of naive targets were 68.6 Gy2/2 (range, 8.3-154.5 Gy2/2) and 83.5 Gy2/2 (range, 10.5-180.5 Gy2/2), respectively. Median maximum nBED for spinal cord and thecal sac for the re-irradiated targets were 58.6 Gy2/2 (range, 17.7-140 Gy2/2) and 70.5 Gy2/2 (range, 21.7-141.3 Gy2/2), respectively. No patient developed radiation related myelopathy during the follow-up period. CONCLUSION: Cyberknife radiotherapy is clinically effective and safe for spinal metastases, even in previously irradiated patients.


Assuntos
Robótica/métodos , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/radioterapia , Estudos Prospectivos , Adulto Jovem
13.
Bioresour Technol ; 101(21): 8244-51, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20598876

RESUMO

Assessment of compost maturity is crucial for achieving high quality compost in order to guarantee its marketability. In this context, a novel technique that combines fluorescence excitation-emission matrices (EEMs) with parallel factor (PARAFAC) analysis to assess compost maturity is presented. A total of 60 fluorescence EEMs of composts were successfully decomposed into a three-factor model using PARAFAC analysis. Components 1 [excitation/emission (Ex/Em) wavelengths=(230, 330)/410] and 2 [Ex/Em wavelengths=(250, 350)/450] were attributable to humic-like and fulvic-like substances, whereas component 3 [Ex/Em wavelengths=(220, 280)/340] belonged to protein-like substances. Pearson correlation analysis between the common maturity indices and log scores of three components demonstrated that components 1 and 3 are more suitable to assess compost maturity than component 2. These results reveal that EEM-PARAFAC could be applied as a valuable tool for assessing compost maturity, given its high sensitivity and selectivity.


Assuntos
Modelos Químicos , Solo/análise , Espectrometria de Fluorescência/métodos , Análise Fatorial , Compostos Orgânicos , Análise de Componente Principal , Análise de Regressão , Água/química
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