检索结果-南通市图书馆

Nitric Oxide/Peroxynitrite Redox Imbalance in Endothelial Cells Measured with Amperometric Nanosensors

American Journal of Analytical Chemistry 2013年第10期4卷 30-36页

作者： Andrzej Burewicz hazem dawoud Lu-Lin Jiang Tadeusz Malinski Department of Chemistry and Biochemistry Ohio University Athens Ohio USA

The cytoprotective messenger nitric oxide (NO) and cytotoxic peroxynitrite (ONOO-) are the main components of oxidative stress and can be generated by endothelial cells. A tandem of electrochemical nanosensors (diameter 200-300 nm) were used to measure, in situ, the balance between NO and ONOO-produced by human umbilical vein endothelial cells (HUVEC’s). The amperometric nanosensors were placed 5 ± 2 μm from the surface of the endothelial cells and the concentration of NO and ONOO- was measured at 630 mV and -300 mV (vs Ag/AgCl) respectively. Normal, functional, endothelial cells produced maximal 450 ± 25 nmol.L-1 of NO and 180 ± 15 nmol.L-1 of ONOO- in about 3 s, after stimulation with calcium ionophore. The in situ measurements of NO and ONOO- were validated using nitric oxide synthase inhibitor L-NMMA, ONOO- scavenger Mn(III) porphyrin, and superoxide dismutase (PEG-SOD). The ratio of NO concentration to ONOO- concentration ([NO]/[ONOO-]) was introduced for quantification of both, the redox balance and the level of the nitroxidative stress in the endothelium. [NO]/[ONOO-] was 2.7 ± 0.1 in a functional endothelium. The model of the dysfunctional endothelium was made by the treatment of HUVEC’s with angiotensin II for 20 min. Dysfunctional HUVEC’s produced only 115 ± 15 nmol.L-1 of NO, but generated a significantly higher concentration of ONOO- of 490 ± 30 nmol.L-1. The [NO]/[ONOO-] ratio decreased to 0.23 ± 0.14 in the dysfunctional endothelium. Electrochemical nanosensors can be effectively used for in situ monitoring of changing levels of nitroxidative/ oxidative stress, and may be useful in early medical diagnosis of the cardiovascular system.

关键词： Nanosensors Nitric Oxide Peroxynitrite Endothelium Oxidative Stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Role of Chest X-Ray in Monitoring Lung Changes among COVID-19 Patients in Gaza Strip

引用

Open Journal of Medical Imaging 2021年第2期11卷 29-47页

作者： Mahmoud Mousa Marwan Matar Yasser Al Ajerami Ahmad Naijm Khalid Abu Shab Sadi Jaber Fouad SJaber hazem dawoud Department of Radiology Gaza-European Hospital Gaza Strip Palestine Department of Medical Imaging Applied Medical Sciences Al-Azhar University Gaza Strip Palestine Department of Nursing Applied Medical Sciences Al-Azhar University Gaza Strip Palestine Department of Radiology Nasser Medical Complex Gaza Strip Palestine Valley Fever Institute UCLA Kern Medical Bakersfield USA Department of Chemistry and Biochemistry Ohio University Athens USA

Objective: To investigate the time course and findings severity of COVID-19 infection at chest radiography based on a 6-point radiological severity score, and correlates these with patients’ age and gender. Methods: This is a retrospective study of COVID-19 patients who were admitted at European Gaza Hospital and evaluated between October 6, 2020, and November 30, 2020. Baseline and serial chest radiographs, up to 4 images per patient, were reviewed and assessed for predominant pattern, side, and location of lung opacity. Utilized a 6-point scoring system, which divides the chest X-ray into 6 zones, to assess chest X-ray changes and correlate them with the severity of infection, age, and gender of patients. Results: The study included 136 COVID-19 patients: (51/136, 37%) were males and (85/136, 62.5%) were females, while age ranged from 7 months to 90 years with a mean age of 41.7 ± (19.5) years. Negative Chest x-rays were more observed than positive images. Ground-glass opacity was the most frequent pattern with a decreasing trend from 1st to 4th chest X-ray (from 33.8% to 3.7%), followed by consolidation (from 16.2% to 2.9%). Also, the commonest pattern of opacity was seen in peripheral areas (27/136, 19.9%), lower zone location (23/136, 16.9%), and bilateral opacity involvement (43/136;31.6%). No significant correlation was noticed between the patient’s gender, age, and severity score (P > 0.05). Conclusions: The 6-point chest X-ray severity score as a predictive tool in assessing the severity due to provide an assessment of the progression or regression pathway.

关键词： Chest X-Rays COVID 19 Lung Changes Scoring System Gaza Strip

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：