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1.
Huan Jing Ke Xue ; 44(9): 5214-5221, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699839

RESUMO

Due to the wide sources of biomass raw materials and the lack of limits for the endogenous pollutants in biochar and their dosage, some biochar with high endogenous pollutants may be used for environmental remediation, which results in potential environmental risks. In this study, three biochars were prepared from the straws of Pennisetum sp. grown in clean, moderately polluted and highly polluted soils, respectively. The total endogenous copper (Cu) and cadmium (Cd), acid-soluble fraction, and persistent free radical (PFRs) distribution in biochars were investigated, and their biotoxicities were evaluated based on wheat root elongation inhibition rate and antioxidant enzyme activity. The results indicated that total Cu in Jiuniu biochar from the highly polluted soil and total Cd in Shuiquan biochar from the moderately-polluted soil were 3.73 and 4.43 times higher than that in Hongrang biochar from the clean soil, respectively. Moreover, acid-soluble Cu in Jiuniu biochar was 3.32 and 2.84 times higher than that in Shuiquan and Hongrang biochar, respectively, and acid-soluble Cd in Shuiquan and Jiuniu biochar was 7.95 and 5.11 times higher than that in Hongrang biochar, respectively. All three biochars had PFRs with adjacent oxygen atoms centered on carbon and followed the order of Hongrang>Jiuniu>Shuiquan. Three biochar leaching solutions significantly inhibited wheat root elongation but enhanced the enzyme activities of SOD, POD, and CAT for the wheat seedlings compared with that in the control. In particular, the highest inhibition rate (27.7%) was found in Jiuniu biochar. This study indicated that the interaction of endogenous heavy metals and PFRs in biochar exhibited significant biotoxicity to wheat seedlings. In the future, more attention should be paid to the potential environmental toxicity of endogenous pollutants from biochar to avoid new environmental pollution problems.


Assuntos
Poluentes Ambientais , Pennisetum , Cádmio/toxicidade , Poluição Ambiental , Antioxidantes , Plântula
2.
Acta Radiol ; 56(5): 552-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24917607

RESUMO

BACKGROUND: The H7N9 strain of bird flu is a new type of avian flu that was identified at the end of March 2013. The disease is concerning because most patients have become severely ill. PURPOSE: To study the X-ray and computed tomography (CT) findings of early H7N9 avian influenza cases. MATERIAL AND METHODS: Chest radiography and CT were performed in six patients with H7N9 avian influenza within 1-20 days after onset. The CT examinations included conventional spiral CT and high-resolution CT. The findings on the radiography and CT images were analyzed. RESULTS: Abnormal X-ray and CT findings were present in all of the patients. All of the cases had acute onset. In the early stage, the right lung was more commonly affected (particularly in the right upper and middle lobes). The lesions rapidly expanded to the entire lungs and were characterized primarily by ground-glass opacities (GGOs) combined with consolidation. Diffuse GGO was observed in all six cases (1 was symmetric, and 5 were non-symmetric). Local consolidation was found in four cases, and lobar consolidation was found in two cases. Normal lung tissue was observed between the lesions. Pleural thickening was common and was combined with pleural/pericardial effusion or mediastinal lymph node enlargement. Reticular changes, centrilobular nodules, and the tree-in-bud sign were observed in some cases, but reticular changes, bronchial wall thickening, and hyperinflation were not found. CONCLUSION: Radiological changes associated with both acute pneumonia and acute interstitial inflammation were observed in early H7N9 avian influenza cases. Serial chest X-rays were useful for the diagnosis and severity assessment of the disease. CT may provide a more accurate assessment of the lung pathology.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Influenza Humana/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Espiral/métodos
3.
Acta Radiol ; 56(1): 105-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24518686

RESUMO

BACKGROUND: Endovascular treatment of large and giant intracranial aneurysms and long-term results of angiographic follow-up of these aneurysms treated endovascularly are not known currently. PURPOSE: To investigate the outcome of endovascular treatment of large and giant aneurysms and the long-term angiographic follow-up results. MATERIAL AND METHODS: A retrospective analysis of all patients with endovascular treatment of large and giant aneurysms between 1998 and 2009 was performed. There were 90 large or giant aneurysms treated with coiling alone, stent-assisted coiling, covered-stent deployment, or parent artery occlusion (PAO) in 88 patients (female/male, 54/34; age range, 23-92 years; mean age, 56 years). RESULTS: Immediately after the initial endovascular embolization procedure, complete occlusion was achieved in 56.7%, near complete occlusion in 37.8%, and incomplete occlusion in 5.5%. The total periprocedural complication rate excluding subarachnoid hemorrhage (SAH)-induced vasospasm was 10.2% with a mortality rate of 2.3%. Follow-up angiography was performed in all of the aneurysms with the longest follow-up duration of 131 months. Among 38 aneurysms initially treated with coiling alone and 17 initially treated with stent-assisted coiling, 22 (57.9%) and four (23.5%) recurred, respectively, during follow-up. No recurrence occurred in aneurysms initially treated with covered-stent deployment or PAO. Aneurysm recurrence was predominantly seen in older and female patients, in larger aneurysms, and in aneurysms treated with coiling alone. Twenty-three aneurysms were successfully retreated endovascularly. CONCLUSION: Endovascular intervention with coiling alone or stent-assisted coiling for large and giant cerebral aneurysms is not very effective, while covered stents are more promising. Better endovascular devices are needed to obtain more secure closure.


Assuntos
Prótese Vascular , Angiografia Cerebral , Stents Farmacológicos , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
4.
Molecules ; 19(11): 19097-113, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25415474

RESUMO

The aroma-active compounds in Jinhua ham processed and stored for 9, 12, 15 and 18 months were extracted by dynamic headspace sampling (DHS) and solvent-assisted flavor evaporation (SAFE) and analyzed by gas chromatography-olfactometry-mass spectrometry (GC-O-MS). In GC-O-MS, volatile compounds were identified based on their mass spectrum, linear retention index (LRI), odor properties, or reference compound comparisons. The results showed that a total number of 81 aroma-active compounds were identified by GC-O-MS. Among them, acids (such as acetic acid, butanoic acid and 3-methylbutanoic acid), saturated aldehydes (such as hexanal, heptanal, octanal and 3-methylbutanal), benzene derivatives (such as benzeneacetic acid), ester and lactone (such as γ-nonalactone and γ-decalactone) were identified as critical compounds in Jinhua ham aroma. The results also indicated that the type and content of the odorants increased significantly with the duration of the fermentation period.


Assuntos
Produtos da Carne/análise , Aldeídos/química , Benzeno/química , Ésteres/química , Fermentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lactonas/química , Solventes/química
5.
Acta Radiol ; 53(8): 900-7, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22919051

RESUMO

BACKGROUND: MRI is of increasing importance in the diagnostic evaluation of gastrointestinal diseases, with depiction of mucosal enhancement obtained with conventional intravenous contrast. Routine clinical use of contrast agents has been carried out using intravenous injection for mucosal imaging. Contrast agents that specifically target the intestinal mucosa are therefore needed to improve clinical imaging of the mucosal surface. PURPOSE: To synthesize a novel contrast agent for gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles and observe the absorption of the nanoparticles in the colon wall of healthy rats by MR imaging in vivo. MATERIAL AND METHODS: A contrast agent was successfully synthesized by a modified emulsion coalescence method, and the resulting agents were characterized in detail by dynamic light-scattering spectroscopy and inductively coupled plasma emission spectroscopy. The cytotoxicity of Gd-chitosan nanoparticles was evaluated by an MTT assay. Gadolinium-chitosan (Gd@chitosan) nanoparticles were administered to the colon mucosa of healthy rats by rectal administration, and MRI scans in vivo were carried out with a 3.0 T imaging scanner at various time points. RESULTS: The prepared Gd@chitosan nanoparticles were ~420 nm in diameter with a 74.4% Gd-DTPA content. The MTT assay indicated little cytotoxicity. MRI results showed that nanoparticles can be retained in both the stratum submucosum and epithelial cells of the colon for almost 80 min. Transmission electron microscopy images further revealed that Gd@chitosan nanoparticles were localized inside the mucosal cells or intercellular space, while tissue from Gd-DTPA aqueous solution administration showed nothing. Due to the infusion of Gd@chitosan nanoparticles, the MR signal intensity of colon mucosa increased from about 6% to 35%, and the contrast enhancement was highest at 20 min after administration. CONCLUSION: Gd@chitosan nanoparticles with high Gd-DTPA content were successfully prepared for use as a novel MRI contrast agent. All results indicated that rectally administered Gd@chitosan nanoparticles have the potential for MRI diagnosis of colon mucosal disease.


Assuntos
Quitosana , Colo/citologia , Gadolínio DTPA , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética , Nanopartículas , Administração Retal , Animais , Sobrevivência Celular , Quitosana/farmacocinética , Quitosana/toxicidade , Colo/metabolismo , Colo/ultraestrutura , Meios de Contraste/farmacocinética , Estudos de Viabilidade , Gadolínio DTPA/farmacocinética , Gadolínio DTPA/toxicidade , Células HeLa , Humanos , Absorção Intestinal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/ultraestrutura , Masculino , Nanopartículas/toxicidade , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Valores de Referência
6.
Rheumatology (Oxford) ; 50(9): 1712-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21693547

RESUMO

OBJECTIVE: We sought to evaluate the use of high-resolution three-dimensional time of flight (3D TOF) magnetic resonance angiography (MRA) at 3 Tesla in the visualization of digital arteries in SSc patients. METHODS: A total of 33 patients with SSc [32 females and 1 male; mean (s.d.) age 37.0 (10.2) years; median number of years since onset of RP 3.4 (2.8) years] and 7 healthy controls [6 females and 1 male; mean (s.d.) age 30.7 (3.5) years] were examined on a 3T MR system. A modified high spatial resolution (voxel size = 0.35 × 0.35 × 0.5 mm(3)) 3D TOF MRA (repetition time/echo time = 19/4.4 ms, flip angle = 15°, slice thickness = 1 mm) was performed during a total scan time of 8 min 22 s. The source images and maximum intensity projection reconstruction were studied; the digital arteries count and lumen area of the selective section of the vessel were measured independently by two experienced radiologists and compared with that of the control ones; and a four-level grading system was made according to the severity. Statistical analysis was performed with t-test and P < 0.05 was used as the criterion. RESULTS: We detected the eight digital arteries in the four fingers (without the thumb) of each case and got a 47.58% presentation in general in the SSc group, and artery No. 5 had the highest presentation rate (70.97%). Statistics showed that the digital arteries No. 1 (P = 0.058) and No. 3 (P = 0.093) had no difference in the lumen area (P > 0.05). We finally got 3 cases in Grade 1, 14 cases in Grade 2, 9 cases in Grade 3 and 5 cases in Grade 4. CONCLUSION: MRA of the digital arteries in the described technique is a promising method for us to judge the severity of microvascular involvement in finger vessels of SSc patients.


Assuntos
Dedos/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Doença de Raynaud/fisiopatologia , Escleroderma Sistêmico/fisiopatologia , Adulto , Artérias , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Doença de Raynaud/complicações , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico
7.
Med Hypotheses ; 68(3): 656-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17014968

RESUMO

In recent years, magnetic resonance imaging (MRI) have been developed to image atherosclerosis and is emerging as a useful tool to assess the burden of atherosclerosis, whereas the potential influence on the diagnosis and therapy of atherosclerotic disease have not been fully determined. MRI allows for three-dimensional evaluation of vascular structures and outstanding depiction of various components of the atherosclerotic plaque. The self-contained intravascular MRI probe appears to hold promise in the identification of high-risk coronary and peripheral atherosclerotic lesions. Molecular and targeted contrast MRI can offer exciting possibilities of direct visualization of biologic processes within atherosclerotic tissue. The addition of quantitative hydrogen 1 magnetic resonance spectroscopy and diffusion weighted imaging within atherosclerotic plaques can provide important data on the biological activity of potentially vulnerable lesions. Therefore, we hypothesized that accurate magnetic resonance imaging of atherosclerotic plaques maybe further affect and change future strategies for the diagnosis and therapy of atherosclerotic disease.


Assuntos
Aterosclerose/diagnóstico , Aterosclerose/patologia , Imageamento por Ressonância Magnética/métodos , Humanos , Placa Amiloide/patologia , Reprodutibilidade dos Testes
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