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1.
World J Pediatr ; 17(4): 419-428, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34110593

RESUMO

BACKGROUND: Asthma has been a global problem, especially in children. We aim to evaluate the contemporary prevalence and influencing factors of asthma among children aged 3-7 years in Shanghai, China. METHODS: A random sample of preschool children was included in this study. The International Study of Asthma and Allergies in Childhood questionnaire was adopted to assess the childhood asthma. Multivariable logistic regression models were used to evaluate the associations between independent variables and childhood asthma. RESULTS: Of 6389 preschool children who were invited to take part in this study, 6163 (response rate: 96.5%) completed the questionnaire and were included in the analysis. The overall prevalence of asthma was 14.6% which increased more than six folds from 2.1% in 1990. Being male, younger age, preterm delivery, being born in spring or autumn, being delivered by elective cesarean section without indication, miscarriage, high socioeconomic status, having allergy history, and exposure to passive smoking, latex paint, and dust were potential risk factors for childhood asthma. Spending more time outdoors (> 30 min/day), having indoor plants, and cleaning rooms more frequently were potential protective factors. CONCLUSIONS: The prevalence of childhood asthma in Shanghai has increased dramatically during the past three decades. The findings about risk and protective factors of childhood asthma could be used to develop appropriate strategies to prevent and control childhood asthma in Shanghai and in other similar metropolitan cities.


Assuntos
Asma , Cesárea , Asma/diagnóstico , Asma/epidemiologia , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Prevalência
2.
World J Clin Cases ; 7(21): 3463-3473, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31750329

RESUMO

BACKGROUND: Several studies have demonstrated the feasibility and effectiveness of using ultrasound elastography to assess liver tissue stiffness. Virtual touch imaging quantification (VTIQ) based on acoustic radiation force impulse imaging has been developed as a latest and noninvasive method for assessing liver stiffness in children. AIM: To determine the standard value in healthy children, and to identify possible factors that might influence the VTIQ measurement. METHODS: With the ethical approval, 202 children between 1 month and 15 years old were included in this study. None of them had any liver or systematic diseases. All children had a normal ultrasound scan and normal body mass index (BMI) range. The subjects were divided into four age and BMI groups. The effects of gender, age, liver lobe, measurement depth, and BMI on liver elasticity were investigated. RESULTS: A significant correlation was found between age and shear wave velocity (SWV) value. At measurement depths of 1.5 cm and 2.0 cm in the left lobe, there were significant differences among the age groups. SWV values were significantly negatively correlated with the measurement depth. Gender, liver lobe, and BMI showed no significant effect on the SWV values. Age and BMI may influence the quality of the elastogram. CONCLUSION: VTIQ is a noninvasive technique that is feasible to measure liver stiffness in children. The afore-mentioned velocity value obtained utilizing VTIQ method could be used as reference value for normal liver stiffness in children.

3.
Comput Methods Programs Biomed ; 143: 171-184, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28391815

RESUMO

BACKGROUND AND OBJECTIVE: Segmentation of the femur from the hip joint in computed tomography (CT) is an important preliminary step in hip surgery planning and simulation. However, this is a time-consuming and challenging task due to the weak boundary, the varying topology of the hip joint, and the extremely narrow or blurred space between the femoral head and the acetabulum. To address these problems, this study proposed a semi-automatic segmentation framework based on harmonic fields for accurate segmentation. METHODS: The proposed method comprises three steps. First, with high-level information provided by the user, shape information provided by neighboring slices as well as the statistical information in the mask, a region selection method is proposed to effectively locate joint space for the harmonic field. Second, incorporated with an improved gradient, the harmonic field is used to adaptively extract a curve as the barrier that separates the femoral head from the acetabulum accurately. Third, a divide and conquer segmentation strategy based on the harmonic barrier is used to combine the femoral head part and body part as the final segmentation result. RESULTS: We have tested 40 hips with considerately narrow or disappeared joint spaces. The experimental results are evaluated based on Jaccard, Dice, directional cut discrepancy (DCD) and receiver operating characteristic (ROC), and we achieve the higher Jaccard of 84.02%, Dice of 85.96%, area under curve (AUC) of 89.3%, and the lower error with DCD of 0.52mm. The effective ratio of our method is 79.1% even for cases with severe malformation. The results show that our method performs best in terms of effectiveness and accuracy on the whole data set. CONCLUSIONS: The proposed method is efficient to segment femurs with narrow joint space. The accurate segmentation results can assist the physicians for osteoarthritis diagnosis in future.


Assuntos
Cabeça do Fêmur/diagnóstico por imagem , Fêmur/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Articulação do Quadril , Humanos , Modelos Estatísticos , Reconhecimento Automatizado de Padrão/métodos , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
4.
Comput Biol Med ; 56: 132-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25464355

RESUMO

The accurate tooth partition of dental mesh is a crucial step in computer-aided orthodontics. However, tooth boundary identification is not a trivial task for tooth partition, since different shapes and their arrangements vary substantially among common clinical cases. Though curvature field is traditionally used for identifying boundaries, it is normally not reliable enough. Other methods may improve the accuracy, but require intensive user interaction. Motivated by state-of-the-art general interactive mesh segmentation methods, this paper proposes a novel tooth-target partition framework that employs harmonic fields to partition teeth accurately and effectively. In addition, a refining strategy is introduced to successfully segment teeth from the complicated dental model with indistinctive tooth boundaries on its lingual side surface, addressing an issue that had not been solved properly before. To utilise high-level information provided by the user, smart and intuitive user interfaces are also proposed with minimum interaction. In fact, most published interactive methods specifically designed for tooth partition are lacking efficient user interfaces. Extensive experiments and quantitative analyses show that our tooth partition method outperforms the state-of-the-art approaches in terms of accuracy, robustness and efficiency.


Assuntos
Imageamento Tridimensional , Ortodontia/métodos , Cirurgia Assistida por Computador/métodos , Dente , Humanos
5.
Int J Biol Macromol ; 66: 52-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24556120

RESUMO

The aim of this study was to determine the antitumor and antiangiogenic effects of the Schisandra chinensis polysaccharides (SCP) in selected renal cell carcinoma (RCC) cells and evaluate its potential mechanism of action. In vitro, endothelial growth factor (VEGF) secretion by Caki-1 was blockaded in response to SCP treatment for 48h. In vivo, a significant tumor growth inhibition effect was observed after SCP administration for 4 weeks. Moreover, SCP treatment decreased the level of VEGF, CD31 and CD34 in RCC tumor tissues. Further analysis of the tumor inhibition mechanism indicated that the number of apoptotic tumor cells increased significantly; the expression of Bax and p53 increased; and the expression of Bcl-2 decreased dramatically in transplanted tumor tissues following SCP administration. These results indicated that the potential mechanisms involved by which SCP exerted its antitumor and antiangiogenic activity might be associated with the up-regulation of Bax and p53, downregulation of Bcl-2, as well as the reduction of VEGF, CD31 and CD34 in xenografted tumors. These findings demonstrated that the SCP is a potential antitumor agent for RCC treatment.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Polissacarídeos/farmacologia , Schisandra/química , Animais , Antígenos CD34/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Humanos , Neoplasias Renais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteína Supressora de Tumor p53 , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína X Associada a bcl-2/metabolismo
6.
Tumour Biol ; 35(6): 5369-74, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24504681

RESUMO

This study is the first to investigate the anticancer effect of Schisandra chinensis polysaccharide (SCP) in renal cell carcinoma (RCC) cells. The results revealed that SCP treatment showed high cytotoxic potency in Caki-1 cells by inducing apoptosis, which is associated with the disruption of mitochondrial membrane potential (MMP), release of cytochrome c into the cytosol, increase of Bax/Bcl-2 ratio, activation of caspase-3/9, and cleavage of poly(ADP-ribose) polymerase (PARP). Furthermore, pan-caspase inhibitor (z-VAD-fmk) significantly blocked SCP-induced apoptosis and PARP cleavage in Caki-1 cells. As well, we also observed that SCP inhibited the phosphorylation of ERK1/2, whereas it had no significant inhibition effect on the phospho-p38 and phospho-JNK activity. All the above parameters provided scientific evidence that SCP induced mitochondrial-mediated apoptosis in Caki-1 cells through the inactivation of ERK pathways, which may shed further light on its potential application as a cancer chemopreventive agent against RCC.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/tratamento farmacológico , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Neoplasias Renais/tratamento farmacológico , Mitocôndrias/fisiologia , Polissacarídeos/farmacologia , Schisandra/química , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Humanos , Neoplasias Renais/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos
7.
Int J Oncol ; 31(5): 985-1007, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17912425

RESUMO

Subtraction hybridization applied to a 'differentiation therapy' model of cancer employing human melanoma cells resulted in the cloning of melanoma differentiation associated gene-7/interleukin-24 (mda-7/IL-24). Initial studies confirm an inverse correlation between mda-7 expression and melanoma development and progression. Forced expression of mda-7 by means of a plasmid or via a replication incompetent adenovirus (Ad.mda-7) promotes growth suppression and induces apoptosis in a broad array of human cancers. In contrast, mda-7 does not induce growth suppressive or toxic effects in normal cells. Based on structure (containing an IL-10 signature motif), secretion by cells (including subsets of T-cells) and location on chromosome 1q (in an area containing IL-10-family genes), mda-7 has now been renamed mda-7/IL-24. Studies by several laboratories have uncovered many of mda-7/IL-24's unique properties, including cancer-specific apoptosis-induction, cell cycle regulation, an ability to inhibit angiogenesis, potent 'bystander antitumor activity' and a capacity to enhance the sensitivity of tumor cells to radiation, chemotherapy and monoclonal antibody therapy. Moreover, based on its profound cancer tropism, substantiated by in vivo human xenograft studies in nude mice, mda-7/IL-24 (administered as Ad.mda-7) was evaluated in a phase I clinical trial in patients with melanomas and solid cancers. These studies document that mda-7/IL-24 is well tolerated and demonstrates evidence of significant clinical activity. In these contexts, mda-7/IL-24 represents a unique cytokine gene with potential for therapy of human cancers. The present review focuses on three unique properties of mda-7/IL-24, namely its potent 'bystander antitumor activity', ability to sensitize tumor cells to radiation, and its antiangiogenesis properties. Additionally, an overview of the phase I clinical trial is provided. These studies affirm that mda-7/IL-24 has promise for the management of diverse cancers.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Interleucinas/farmacologia , Radiossensibilizantes/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ensaios Clínicos Fase I como Assunto , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Humanos , Interleucinas/genética , Interleucinas/uso terapêutico , Invasividade Neoplásica , Transdução de Sinais/efeitos dos fármacos , Transgenes
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