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1.
J Environ Sci (China) ; 99: 324-335, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183711

RESUMO

The hydroxyl radical (•OH) has a crucial function in the oxidation and removal of many atmospheric compounds that are harmful to health. Nevertheless, high reactivity, low atmospheric abundance, determination of hydroxyl, and hydroperoxyl radical's quantity is very difficult. In the atmosphere and troposphere, hydroperoxyl radicals (HO2) are closely demanded in the chemical oxidation of the troposphere. But advances in technology have allowed researchers to improve the determination methods on the research of free radicals through some spectroscopic techniques. So far, several methods such as laser-induced fluorescence (LIF), high-performance liquid chromatography (HPLC), and chemical ionization mass spectroscopy have been identified and mostly used in determining the quantity of hydroxyl and hydroperoxyl radicals. In this systematic review, we have advised the use of scavenger as an advance for further researchers to circumvent some of these problems caused by free radicals. The primary goal of this review is to deepen our understanding of the functions of the most critical free radical (•OH, HO2) and also understand the currently used methods to quantify them in the atmosphere and troposphere.


Assuntos
Atmosfera , Radical Hidroxila , Radicais Livres , Oxirredução
2.
J Ethnopharmacol ; 266: 113411, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32980482

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Tiantian capsule (TTC), as a functional food, which consists of four herb medicines, including Aloe vera Burm.f. (25%), leaf juices, dried; Cucurbita moschata Duch. (25%), fructus, dried; Poria cocos (Schw.) Wolf. (12.5%), sclerotium, dried; Tremella fuciformis Berk. (12.5%), fruiting bodies, dried, and one extract xylooligosaccharides (25%) from Maize Cob by enzymolysis, has been commonly used in China to ameliorate constipation. AIM OF THE STUDY: The aim of the work is to elucidate the potential laxative mechanisms of TTC in loperamide-induced constipated rats. MATERIALS AND METHODS: LC-MS/MS was employed for analyzing the TTC extract. The gastrointestinal transit was evaluated by X-ray. The H&E and Alcian-Blue stain were applied to determine the changes of goblet cells and mucus layer, respectively. Meanwhile, levels of neurotransmitters were evaluated by enzyme-linked immunosorbent assay. The protein expressions were also measured by immunohistochemistry and Western blot. RESULTS: Our results showed that TTC administration attenuated constipation responses in aspects of fecal pellets number, water content of feces, stomach emptying and gastrointestinal transit. Further investigations revealed that TTC treatment not only induced the recovery of neurotransmitters, such as motilin, substance P, somatostatin, endothelin and vasoactive intestinal peptide, but also up-regulated the expressions of c-kit and stem cell factor (SCF). Additionally, the number of goblet cells and thickness of the mucus layer were elevated, and the guanylate cyclase C-cGMP signal pathway was also up-regulated after TTC treatment. CONCLUSION: Our findings demonstrated that the laxative effect of TTC in constipation rats is probably due to the regulation of bowel movement and intestinal fluid secretion.


Assuntos
Constipação Intestinal/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Trânsito Gastrointestinal/efeitos dos fármacos , Laxantes/farmacologia , Animais , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Alimento Funcional , Laxantes/química , Loperamida/toxicidade , Masculino , Medicina Tradicional Chinesa , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
3.
Magn Reson Imaging ; 75: 100-106, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33096226

RESUMO

OBJECTIVE: To test the performance of free-breathing Dynamic Contrast-Enhanced MRI (DCE-MRI) using a radial volumetric interpolated breath-hold examination (VIBE) sequence combined with diffusion-weighted imaging (DWI) for quantitative solitary pulmonary nodule (SPN) assessment. METHODS: A total of 67 SPN cases receiving routine MRI routine scans, DWI, and dynamic-enhanced MRI in our hospital from May 2017 to November 2018 were collected. These cases were divided into a malignant group and a benign group according to the characteristics of the SPNs. The quantitative DCE-MRI parameters (Ktrans, Kep, Ve) and apparent diffusion coefficient (ADC) values of the nodules were measured. RESULTS: The Ktrans and Kep values in the malignant group were higher than those in the benign group, while the ADC values in the malignant group were lower than those in the benign group. Furthermore, the Ktrans value of adenocarcinoma was higher than that of squamous cell carcinoma and small cell carcinoma (P < 0.05). The Ve value was significantly different between non-small cell carcinoma and small cell carcinoma (P < 0.05). With an ADC value of 0.98 × 10-3 mm2/s as the threshold, the specificity and sensitivity to diagnose benign and malignant nodules was 90.6% and 80%, respectively. CONCLUSION: High-temporal-resolution DCE-MRI using the r-VIBE technique in combination with DWI could contribute to pulmonary nodule analysis and possibly serve as a potential alternative to distinguish malignant from benign nodules as well as differentiate different types of malignancies.


Assuntos
Suspensão da Respiração , Imagem de Difusão por Ressonância Magnética , Processamento de Imagem Assistida por Computador , Nódulo Pulmonar Solitário/diagnóstico por imagem , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/fisiopatologia , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/fisiopatologia , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/fisiopatologia
4.
BMC Med Imaging ; 20(1): 112, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008318

RESUMO

BACKGROUND: Lung cancer screening revealed that people with small pulmonary nodules are mostly asymptomatic and that some of these people are at risk of developing lung cancer, so we intended to explore the repeatability of small lung nodule measurement in low-dose lung screening. METHODS: We scanned eight ground-glass nodules (GGNs) and solid nodules, with diameters of 3, 5, 8, and 10 mm. They were divided according to the different combination schemes of tube voltage (KV) and tube current (mA) as 70, 80, 100, and 120 KV, and currents of nine tubes were divided as 20, 30, 40, 50, 60, 70, 80, 90, and 100 mAs. RESULTS: Compared with the conventional dose group (120 kVp, 100 mAs), the nodule diameter and solid nodule volume measured by all scanning combinations were more consistent (P > 0.05), the volumes of 10 mm GGNs combinations were consistent (P > 0.05), the volumes of 8 mm GGNs were consistent (P > 0.05), the volumes of 5 mm GGNs combinations were consistent (P > 0.05), and the volumes of 3 mm were consistent (P > 0.05). CONCLUSION: In lung cancer screening, CT parameters should be as follows: tube voltage is more than 80 kVp, and tube current is 80 mAs in order to meet the requirements for the accurate measurement of the diameter and volume of pulmonary nodules.

5.
Cancer Manag Res ; 12: 6019-6031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765101

RESUMO

Purpose: To predict multiple prognostic factors of HCC including histopathologic grade, the expression of Ki67 as well as capsule formation with intravoxel incoherent motions imaging by extracting the histogram metrics. Patients and Methods: A total of 52 patients with HCC were recruited with the MR examinations undertaken at a 3T scanner. Histogram metrics were extracted from IVIM-derived parametric maps. Independent student t-test was performed to explore the differences in metrics across different subtypes of prognostic factors. Spearman correlation test was utilized to evaluate the correlations between the IVIM metrics and prognostic factors. ROC analysis was applied to evaluate the diagnostic performance. Results: According to the independent student t-test, there were 18, 4, and 8 IVIM-derived histogram metrics showing the capability for differentiating the subtypes of histopathologic grade, Ki67, and capsule formation, respectively, with P-values of less than 0.05. Besides, there existed a lot of significant correlations between IVIM metrics and prognostic factors. Finally, by integrating different histogram metrics showing significant differences between various subgroups together via establishing logistic regression based diagnostic models, greatest diagnostic power was obtained for grading HCC (AUC=0.917), diagnosing patients with highly expressed Ki67 (AUC=0.861) and diagnosing patients with capsule formation (AUC=0.839). Conclusion: Multiple prognostic factors including histopathologic grade, Ki67 expression status, and capsule formation can be accurately predicted with assistance of histogram metrics sourced from a single IVIM scan.

6.
J Environ Sci (China) ; 95: 58-64, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653193

RESUMO

Hydroxyl free radicals (OH radicals) play the main role in atmospheric chemistry and their involving reactions are the dominant rate determining step in the formation of secondary fine particulate matter and in the removal of air pollutants from the atmosphere. In this paper, we studied the seasonal variation characteristics of OH radicals during the daytime in Lanzhou and explored the potential formation mechanism of high concentration OH radicals. We found that the OH radicals in four seasons was 2.7 × 106, 2.6 × 106, 3.1 × 106, and 2.2 × 106 cm-3, respectively. Since the rainfall was concentrated in summer, the wet deposition had a significant effect on removing OH radicals. Among the four pollutants (including ozone (O3), volatile organic compounds (VOCs), nitrogen dioxide (NO2) and fine particulate matter (PM2.5)), the variation of OH radicals were closely related to ozone concentration especially in spring and summer. In autumn, the correlation between PM2.5 and OH radicals were the closest among the observing pollutants and its formation mechanism was different conventional regeneration pathway. In Event 1, high concentration of ozone was the main source of OH radicals; under the high humidity condition, except for ozone, the multiple factors including VOCs, NO2 and PM2.5 interplayed and leaded to the Event 2.


Assuntos
Poluentes Atmosféricos/análise , Ozônio/análise , Atmosfera , Monitoramento Ambiental , Radical Hidroxila/análise , Material Particulado/análise , Estações do Ano
7.
J Cancer Res Ther ; 16(2): 343-349, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32474522

RESUMO

Aim: This study was to evaluate the value of diffusion-weighted imaging (DWI) in predicting the efficacy of radiotherapy for esophageal cancer from xenograft model level. Subjects and Methods: Thirty-two tumor-bearing mice from the Eca-109 cell line nude mice models were established. The experimental group (n = 16) received a single dose of 15 Gy (6MV X-ray), whereas the control group (n = 16) did not receive any treatment. The tumor volume and apparent diffusion coefficient (ADC) were obtained. The cell density, tissue necrosis ratio, and CD31 expression were determined at matched time points. Results: The tumor volume was smaller in the experimental group than in the control group (P < 0.05) on the 7th day after radiotherapy (1.580 ± 0.965 cm3 vs. 2.671 ± 0.915 cm3). The ADC values were higher in the experimental group than in the control group on the 3rd day (P < 0.05) (998.15 ± 163.76 ×10- 6 mm2/s vs. 833.32 ± 142.15 ×10- 6 mm2/s). On the 3rd day after radiotherapy, the differences in cell density and necrosis ratio between the two groups were statistically significant; the tumor cell density was lower in the experimental group (25.56 ± 1.40%) than in the control group (33.48 ± 4.18%) (P < 0.05), and the proportion of tissue necrosis was higher in the experimental group (32.19 ± 1.21%) than in the control group (29.16 ± 2.16%) (P < 0.05). The negative and weak positive rate of CD31 expression in the experimental group was higher than the control group, whereas the generally positive and strong positive rate of CD31 expression was significantly lower than the control group in the early stage (P < 0.05). Conclusion: ADC values may change at the early stage before the morphological changes of tumors. Changes in cell density and necrosis ratio of transplanted tumors correspond to the changes in ADC values. DWI can be used for the early prediction of esophageal cancer radiotherapy efficacy.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Esofágicas/radioterapia , Necrose , Lesões por Radiação/patologia , Radioterapia/efeitos adversos , Carga Tumoral/efeitos da radiação , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Valor Preditivo dos Testes , Lesões por Radiação/diagnóstico por imagem , Lesões por Radiação/etiologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Arch Med Res ; 51(5): 419-428, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32418649

RESUMO

BACKGROUND AND OBJECTIVE: To compare the survival of esophageal squamous cell carcinoma (ESCC) patients who received chemoradiotherapy (CRT) or radiotherapy (RT) alone. METHODS: A total of 753 well-matched patients were enrolled. A total of 299 patients were treated with CRT, and 454 patients were treated with RT alone. Propensity score matching (PSM) was performed with the R project. The Kaplan-Meier method was used to calculate survival rates, and the log-rank test was used to assess differences in survival. RESULTS: The response rate was 99.0% with CRT and 98.3% with RT alone (p = 0.651). The 1-, 3-, 5- and 10 year overall survival (OS) rates were as follows: 72.2, 40.1, 30.7 and 13.9% with CRT, 68.1, 35.2%, 23.3 and 12.5% with RT alone (p = 0.033); 73.4, 40.1, 31.0 and 16.1% with concurrent chemoradiotherapy (CCRT); and 68.1, 35.2, 23.3 and 12.5% with RT alone (p = 0.028). There was no significant difference in OS between the CCRT group and the sequential chemoradiotherapy (SCRT) group (p = 0.527). Consolidation chemotherapy (CCT) after CCRT led to a significant increase in the OS rate compared with no CCT after CCRT (p = 0.003). Compared with the OS of patients who received 1∼2 cycles of CCT, the OS of patients who received 3∼4 cycles of CCT was significantly improved (p = 0.011). Acute toxic effects were more severe in the CRT, but no significant differences in late reactions. CRT exhibited more appetite loss and fatigue symptoms than RT alone, and dysphagia of CRT relief more obviously. The CRT group had a significantly lower rate of local control failure than the RT alone group (p = 0.019). CONCLUSIONS: For patients with ESCC, CRT led to a significantly improved OS compared to RT alone, and this trend was more obvious with CCRT. CCT after CCRT prolonged OS, especially in patients who received at least 2 cycles of CCT. CRT can reduce the deaths due to local control failure compared to RT alone.


Assuntos
Quimiorradioterapia/métodos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/radioterapia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
9.
Medicine (Baltimore) ; 99(18): e20074, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32358390

RESUMO

The objective of this study was to develop a venous computed tomography (CT)-based radiomics model to predict the lymph node metastasis (LNM) in patients with non-small cell lung cancer (NSCLC). A total of 411 consecutive patients with NSCLC underwent tumor resection and lymph node (LN) dissection from January 2018 to September 2018 in our hospital. A radiologist with 20 years of diagnostic experience retrospectively reviewed all CT scans and classified all visible LNs into LNM and non-LNM groups without the knowledge of pathological diagnosis. A logistic regression model (radiomics model) in classification of pathology-confirmed NSCLC patients with and without LNM was developed on radiomics features for NSCLC patients. A morphology model was also developed on qualitative morphology features in venous CT scans. A training group included 288 patients (99 with and 189 without LNM) and a validation group included 123 patients (42 and 81, respectively). The receiver operating characteristic curve was performed to discriminate LNM (+) from LNM (-) for CT-reported status, the morphology model and the radiomics model. The area under the curve value in LNM classification on the training group was significantly greater at 0.79 (95% confidence interval [CI]: 0.77-0.81) by use of the radiomics model (build by best 10 features in predicting LNM) compared with 0.51 by CT-reported LN status (P < .001) or 0.66 (95% CI: 0.64-0.68) by morphology model (build by tumor size and spiculation) (P < .001). Similarly, the area under the curve value on the validation group was 0.73 (95% CI: 0.70-0.76) by the radiomics model, compared with 0.52 or 0.63 (95% CI: 0.60-0.66) by the other 2 (both P < .001). A radiomics model shows excellent performance for predicting LNM in NSCLC patients. This predictive radiomics model may benefit patients to get better treatments such as an appropriate surgery.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/patologia , Metástase Linfática , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Humanos , Modelos Logísticos , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos
10.
Cancer Manag Res ; 12: 841-854, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104066

RESUMO

Background and Objective: Compared with tissue biopsy, liquid biopsy is the most preferable non-invasive promising method in personalized medicine, although it has many limitations in isolating circulating tumor cells (CTC). Lung cancer associated mortality is drastically increased due to a shortfall of early-stage detection, which remains a challenge. Herein, we aimed to detect lung cancer at an early-stage using CellCollector device. Methods: 39,627 volunteers underwent low-dose computed tomography; 2508 cases with pulmonary nodules and 7080 with no pulmonary nodules were chosen. After follow-up, 24 patients were diagnosed with early-stage non-small cell lung cancer (NSCLC), and subjected to CTC detection using CellCollector, along with 72 healthy volunteers. Immunofluorescence staining for EpCAM/CKs and CD45 were performed for CTC validation. Results: Fifteen out of twenty-four (stage I, n = 18; stage II, n = 6) early-stage lung cancer patients were found to be CTC-positive, whereas no CTC was found in the control group. Genetic mutation of TP53, ERBB2, PDGFRA, CFS1R and FGFR1 in the CTC revealed 71.6% of the mutation sites similar to the tumor tissues of 13 patients. Molecular characterization revealed higher expression of protein PD-LI in CTC (40%) as compared to tumor tissue (26.7%). Moreover, CTC clusters were detected in 40% of patients. Conclusion: CTC detection using the CellCollector in early-stage NSCLC had a relative high capture rate. Moreover, CTC analysis is a prospective setting for molecular diagnostic in cases when tumor tissue biopsy is not desirable.

11.
Lung Cancer ; 139: 73-79, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31743889

RESUMO

OBJECTIVES: To develop and validate predictive models using clinical parameters, radiomic features and a combination of both for lymph node metastasis (LNM) in pre-surgical CT-based stage IA non-small cell lung cancer (NSCLC) patients. METHODS: This retrospective study included 649 pre-surgical CT-based stage IA NSCLC patients from our hospital. One hundred and thirty-eight (21 %) of the 649 patients had LNM after surgery. A total of 396 radiomic features were extracted from the venous phase contrast enhanced computed tomography (CECT). The training group included 455 patients (97 with and 358 without LNM) and the testing group included 194 patients (41 with and 153 without LNM). The least absolute shrinkage and selection operator (LASSO) algorithm was used for radiomic feature selection. The random forest (RF) was used for model development. Three models (a clinical model, a radiomics model, and a combined model) were developed to predict LNM in early stage NSCLC patients. The area under the receiver operating characteristic (ROC) curve (AUC) value and decision curve analysis were used to evaluate the performance in LNM status (with or without LNM) using the three models. RESULTS: The ROC analysis (also decision curve analysis) showed predictive performance for LNM of the radiomics model (AUC values for training and testing, respectively 0.898 and 0.851) and of the combined model (0.911 and 0.860, respectively). Both performed better than the clinical model (0.739 and 0.614, respectively; delong test p-values both<0.001). CONCLUSION: A radiomics model using the venous phase of CE-CT has potential for predicting LNM in pre-surgical CT-based stage IA NSCLC patients.

12.
Medicine (Baltimore) ; 98(49): e18276, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804368

RESUMO

RATIONALE: Pulmonary benign metastasizing leiomyoma (PBML) is rare, usually occurs in women who underwent hysterectomy during the reproductive years, and has no obvious clinical symptoms. A full understanding of the characteristics of PBML is important for its sequential treatment and prognosis. PATIENT CONCERNS: In this report, a 36-year-old female patient with previous uterine leiomyoma who underwent 3 surgical resections of the uterus, bilateral fallopian tubes, and partial omentum was investigated. The physical examination revealed a tumor in the right lower lobe and mediastinum and a solid nodule in the right middle lobe. DIAGNOSES: Chest computed tomography (CT) confirmed a tumor in the right lower lobe and mediastinum and a solid nodule in the right middle lobe. Further positron-emission tomography computed tomography (PET-CT) with 18F-fluorodeoxyglucose (FDG) of the whole body showed mildly intense accumulation of 18F-FDG in the tumor (maximum standardized uptake value [SUV max], 2.6). A pathological examination then confirmed the presence of fibrous and vascular tissue after CT-guided percutaneous biopsy of the tumor in the right lower lobe. Additionally, surgical resection of the tumor and nodule was performed for histological analysis and immunohistochemical assays for estrogen receptor (ER) and progesterone receptor (PR). INTERVENTIONS: The patient underwent complete tumor surgical resection and nodule wedge resection. OUTCOMES: No postoperative complications occurred. No recurrence or other signs of metastasis were found during an 18-month follow-up observation period. CONCLUSION: In this case, lung and mediastinal metastasis of uterine fibroids was observed. However, depending on only a postoperative histological analysis is insufficient for the diagnosis of PBML. Histological analysis combined with an evaluation of the expression levels of ER and PR is crucial for the diagnosis and treatment of PBML.


Assuntos
Leiomioma/patologia , Neoplasias Pulmonares/secundário , Neoplasias do Mediastino/secundário , Neoplasias Uterinas/patologia , Adulto , Feminino , Humanos , Biópsia Guiada por Imagem , Leiomioma/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/cirurgia , Neoplasias Uterinas/cirurgia
13.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438617

RESUMO

We load the natural active molecules onto the spin film in an array using electrospinning techniques. The electrospun active molecular membranes we obtain in optimal parameters exhibit excellent capacity for scavenging radical. The reaction capacity of three different membranes for free radicals are shown as follow, glycyrrhizin acid membrane > quercetin membrane > α-mangostin membrane. The prepared active molecular electrospun membranes with a large specific surface area and high porosity could increase the interaction area between active molecules and free radicals. Additionally, it also has improved anti-airflow impact strength, anti-contaminant air molecular interference ability, and the ability to capture free radicals.


Assuntos
Eletroquímica/métodos , Radicais Livres/química , Ácido Glicirrízico/química , Membranas Artificiais , Xantonas/química
14.
Sci Total Environ ; 683: 221-230, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31132701

RESUMO

Hydroxyl free radicals play the main role in atmospheric oxidative capacity. The formation of secondary fine particulate matter and the degradation of gaseous pollutants in the troposphere are dominated by hydroxyl free radical reactions. The harmful effect of particulate matters to human health is closely related to the free radicals distributed in the particulate matter phase. In this paper, the distribution of hydroxyl free radicals in near-ground ambient air was studied. The hydroxyl free radicals exist not only in the gaseous phase but also in the particulate phase, especially during heavy haze pollution. It is noteworthy that the concentration of hydroxyl free radicals in the particulate phase is about two times higher than that in the gaseous phase. The possible regeneration mechanisms are proposed. The excited electrons (e-) and holes (h+) formed e- - h+ pairs in particulate matters are identified to play a key role in promoting the regeneration of hydroxyl free radicals in particulate phase. Environmentally persistent free radicals in particulate phase could also further promote the chain reaction of free radicals and ultimately result in explosive regeneration in an environment that has been excited. The correlation between radical concentrations in gas species, particulate phases and particulate number concentration has been summary based on the actual monitoring site including Thermal power plant, Yumen street and Chemical street sites.

15.
J Cancer Res Ther ; 15(2): 291-297, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30964100

RESUMO

Purpose: The aim of the study is to study the feasibility of gamma-ray-detection-based precision dose measurement of 125I seed brachytherapy in solid water. Materials and Methods: Seven group 125I seeds with different activities were put into a hole in the center of solid water individually. Each group had ten seeds, and the seed activity ranged from 1.48 × 107 Bq to 3.7 × 107 Bq. Single-photon emission computed tomography/computed tomography (SPECT/CT) was used to scan the seeds perpendicular to the long axis of the seed, with a slice thickness of 3.75 mm. The radioactive count values (x) of the radioactive concentration around the seeds were collected at a distance of 1-15 mm from the center of the seeds, while the corresponding doses (Y) (Gy) were calculated. SPSS 18.0 was used to analyze the relationship between the count value and the dose. Results: With the same seed activity, the count values became smaller according to the distance from the center of the seeds. The count values at the same point had an increasing trend according to the activity. This is similar to the doses calculated at the same point. There was an exponential relationship between the dose around the 125I seeds, and the radioactive count value detected by SPECT/CT. Correlative curves between the dose and radioactive count value detected by SPECT/CT of different-activity 125I seeds were fitted. The formulas of the dose and radioactive count with different seed activity were in the form of Y = b0 (b1)x. The constant b0 ranged from 1.48 to 3.93, according to the seed activity, while b1 was 1.006 for every seed's activity. Conclusion: The count value around the 125I seed can be detected accurately by SPECT/CT, and then can be quantified. This study provided useful experiment data for the precision measurement of 125I seed implantation. Radiation detection-based dose measurement may become a new noninvasive technology for the dynamic dosimetry verification method after brachytherapy.


Assuntos
Braquiterapia , Radioisótopos do Iodo/análise , Radiometria/métodos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Água/química , Relação Dose-Resposta à Radiação , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Reprodutibilidade dos Testes
16.
J Environ Sci (China) ; 81: 205-213, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30975323

RESUMO

Atmospheric particulate pollution in China has attracted much public attention. Occasionally, the particle number concentration increases sharply in a short time period, which is defined as a "particulate matter explosive increase". Heavy particulate matter pollution not only reduces visibility but also has an adverse effect on human health. Hence, there is an urgent need to discover the causes of particulate matter explosive increase. During this campaign, the particle number concentration and free radicals were measured at a tall building on the campus of Lanzhou University of Technology. Additionally, we examined a series of chemicals to reproduce the observed particulate matter explosive increase in a smog chamber to determine its potential factors. Then, we analyzed the mechanism of particulate matter explosive increase in the presence of free radicals. We found that, among the potential inorganic and organic sources analyzed, a mixture of organic and SO2 in the research region had a major effect on particulate matter explosive increase. Moreover, free radical oxidation has a large effect, especially in the formation of organic particulates.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Radicais Livres/química , Modelos Químicos , Material Particulado/análise , China , Poeira , Tamanho da Partícula
17.
Medicine (Baltimore) ; 98(16): e15322, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31008987

RESUMO

Circumcision is a very common surgical procedure that is performed for medical and traditional purposes in the world. However, many technical of circumcision is needed to improve. Thus, this study introduced a novel method of circumcision that is a refined version of the sleeve technique, termed subcutaneous tissue sparing dorsal slit with new marking, and evaluated the safety and efficacy of this novel method of circumcision.The randomized clinical trial included 93 adult patients with redundant foreskin or phimosis treated from May 2015 to March 2017. Patients were randomly divided into the novel circumcision method (n = 45) or conventional dissection (n = 48). The groups were compared regarding rates of intraoperative hemorrhage, operative time, pain, healing, satisfaction with penis appearance, and relevant adverse events.No patient suffered any obvious complication. Compared with the patients given conventional dissection, the patients who underwent the new surgical device experienced significantly less wound healing time, scar width, and recovery time (P <.05). The new method resulted in greater intraoperative bleeding volume and surgical time (P <.05). The rate of satisfaction with appearance of the penis was significantly higher in the group treated with the novel technique. In addition, the cost of surgery of these 2 methods was similar.Based on the above research, we found that subcutaneous tissue-sparing dorsal slit with new marking technique was an effective and safe procedure for circumcision, and deserved further application in clinical practice.


Assuntos
Circuncisão Masculina/métodos , Adulto , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Circuncisão Masculina/efeitos adversos , Prepúcio do Pênis/cirurgia , Humanos , Masculino , Fimose/cirurgia
18.
Oncol Lett ; 17(1): 355-359, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30655774

RESUMO

This study aimed to evaluate the values of thoracic multi-slice spiral computed tomography (CT) in the diagnosis of incidental pulmonary thromboembolism (IPTE) in patients with malignant tumors. The clinical data and imaging features of a total of 1,684 patients with malignant tumors, treated in the Fourth Hospital of Hebei Medical University, were analyzed retrospectively in order to investigate the types of malignancies, the patients' clinical features, and the emboli-preferred sites. Among the 1,684 patients, 60 patients had experienced IPTE (3.56%), 35 were females (58.33%), 25 were males (41.67%). Lung cancer had the highest incidence (n=22, 36.67%). The most common site of IPTE was the left lower lobe of pulmonary artery (n=46, 76.67%). The imaging results revealed that in 5 patients (8.33%) IPTE did not occur. Thoracic multi-slice spiral CT has a high detection rate of IPTE in patients with malignant tumors. Early diagnosis is helpful for early clinical treatment and has significant importance for patients' prognosis.

19.
Oncol Lett ; 16(2): 2335-2343, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30008937

RESUMO

Imaging of gastric cancer thickness is closely associated with the depth of tumor invasion, which provides guidance for clinical staging and assists the evaluation of the effects of adjuvant therapy. However, it is unclear whether the measurement of thickness is affected by the degree of gastric filling, and its accuracy and reliability are under-reported. The present study aimed to investigate the influence of the degree of gastric filling on the measurement of gastric cancer thickness. A total of 38 patients with advanced gastric cancer who underwent enhanced abdominal computed tomography (CT) scanning at the Department of CT and MR in The Fourth Hospital of Hebei Medical University (Shijiazhuang, China) between July and September 2016 were recruited, consisting of 21 newly diagnosed cases and 17 follow-up cases following non-surgical treatments. Plain scanning (prior to filling) and enhanced scanning in venous phase (following filling) were performed. Axial CT images prior to and following filling of the normal part of gastric wall and the lesions were compared. The same procedure was repeated on these participants 1 month later by the same radiologist, and the results were compared with those obtained previously. Normal gastric wall thickness prior to and following gastric filling was significantly different (all P<0.001) with the most substantial changes observed at the greater curvature. Lesion thickness prior to and following filling was similar in newly diagnosed patients, but significantly different in patients for re-examination (P<0.05). The two thickness measurements in the same patients were consistent. The measured thickness of gastric cancer in newly diagnosed patients was relatively stable, and could be used as an indicator in baseline CT examination. Maintaining a similar degree of gastric filling during re-examination could aid the accurate evaluation of treatment efficacy.

20.
Onco Targets Ther ; 11: 3583-3595, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29950863

RESUMO

Introduction: Melanoma is a deadly malignancy and the poor prognosis of patients with advanced disease is relatively poor. Recent studies indicate that long non-coding RNAs are involved in the pathogenesis of malignant melanoma. This study aims to investigate the role of the long non-coding RNA H19 in melanoma and to explore the underlying molecular mechanisms. Materials and methods: The expression levels of H19 in clinical samples and melanoma cells were determined by quantitative real-time PCR. The cell growth and cell metastasis were assessed by Cell Counting Kit 8, cell invasion and wound healing assays. Cell apoptosis and cell cycle were determined by flow cytometry. Protein levels were determined by Western blotting assay. Results: H19 was highly expressed in melanoma tissues compared to normal adjacent skin tissues, and the tissue expression level of H19 from melanoma patients with metastasis was significantly higher than that from patients without distant metastasis. In addition, the high expression of H19 in melanoma tissues was associated with advanced tumor invasion and TNM stage, distal metastasis, lymph node metastasis and shorter overall survival in patients with melanoma. The in vitro functional assays showed that knockdown of H19 inhibited cell growth, invasion and migration and also induced cell apoptosis as well as G0/G1 arrest in melanoma cells. Further quantitative real-time PCR and Western blot experiments showed that knockdown of H19 differentially regulated the epithelial-mesenchymal transition (EMT)-related gene expressions and reversed EMT in melanoma cell lines. Knockdown of H19 suppressed in vivo tumor growth and modulated the expressions of EMT-related genes in nude mice. Conclusion: The results from this study suggest that upregulation of H19 contributes to melanoma development and progression.

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