Research progress on effects and mechanisms of short-term exposure to ambient fine particulate matter and its components on blood pressure / 环境与职业医学

Elevated blood pressure is one of the major contributors to cardiovascular disease and premature death. The exposure to ambient fine particulate matter (PM2.5) is closely associated with changes in blood pressure, and even short-term exposure to PM2.5 can lead to an increase in blood pressure. PM2.5 is a complex mixture that exerts different toxicities and triggers increased blood pressure through various mechanisms. Therefore, in this article, we provided a comprehensive review of published studies on the effects of short-term exposure to PM2.5 and its components on blood pressure, and elaborated potential mechanisms from four aspects, including oxidative stress and inflammatory response, endothelial dysfunction, autonomic nervous system disorders and hypothalamus-pituitary-adrenal axis activation, and epigenome alteration. Given the limitations of existing research, future prospective studies can be conducted on diverse populations, using more precise exposure measurement methods and multi-omics approaches, to further elucidate the mechanisms underlying the effects of PM2.5 and its various components on blood pressure. The findings would provide a theoretical foundation for effective protection of public health, particularly vulnerable groups.

Neuroprotective effect of uric acid in cerebral ischemia-reperfusion injury / 国际脑血管病杂志

Uric acid is an end product of purine metabolism. A large number of clinical studies have shown that high-level serum uric acid is a good predictor of outcome in patients with acute ischemic stroke. Oxidative stress is the main mechanism of cerebral ischemia-reperfusion injury. As a potent antioxidant, uric acid is considered to have a potential neuroprotective effect in the vascular recanalization treatment, but its specific mechanism remains unclear. This article reviews the neuroprotective mechanism of uric acid in cerebral ischemia-reperfusion injury in order to provide ideas for future research and clinical practice.

Determination of Inhibitory Effects of Inhibitors on the Tumor Necrosis Factor-αConverting Enzyme Using High-Performance Liquid Chromatography / 华中科技大学学报(医学版)

Objective A high-performance liquid chromatography(HPLC)method was modified and used to determine the inhibitory effects of GM6001 and inhibitor A on tumor necrosis factor-α converting enzyme(TACE).Methods TACE and polypeptides substrate were incubated for 15 min at 37°C.Ala-Dpa was added as internal standard of quantitative analysis.Then the solution was analyzed by HPLC.The 55% methanol aqueous solution was used as the mobile phase.The wavelength of detector was 353 nm.The ratio of the peak area of remaining substrate to that of internal standard was determined.And the amounts of inverted substrate could be obtained from calibration curve.The TACE activity could be calculated.Results The relative peak areas of substrate were linearly increased depending on the growth of substrate concentration.The correlation coefficient was 0.996 8 and linear range was from 10 to 400 μmol/L.Precision experiments indicated that the precision was improved obviously by using internal standard method in the determination of TACE activity by HPLC.The values of 50% inhibitory concentration IC50 of GM6001 and inhibitor A determined by the newly proposed method were 317.5 and 175.8 nmol/L,respectively.Conclusion The HPLC method assaying TACE activity with Ala-Dpa as internal standard is more accurate,and more practical for screening of TACE inhibitors.

Efficacy of diclofenac diethyamine emulgel on the prevention of PICC-induced mechanic phlebitis / 中华护理杂志

Objective To investigate the efficacy of externally applied diclofenac diethylamine emulgel on the prevention of PICC-induced mechanic phlebitis. Methods One hundred cancer patients with PICC were divided into two groups. diclofenac diethylamine emulgel and mucopolysaccharide polysulfate cream were applied three times a day for 7 days after catheterization in the two groups,respectively. Results There was no significant difference on the incidence of mechanic phlebitis between the two groups (4% vs. 8%,P>0.05). Conclusion The efficacy of externally applied diclofenac diethylamine emulgel on the prevention of PICC-induced mechanic phlebitis is the same as mucopolysaccharide polysulfate cream. Except their common virtue of convenient and simple operation,the price of diclofenac diethylamine emulgel is lower than mucopolysaccharide polysulfate cream and worthy to be spread in clinical practice.

The value of contrast enhanced ultrasound in diagnosis of benign and malignant prostatic neoplasms / 中华超声影像学杂志

Objective To evaluate the value of transrectal contrast enhanced ultrasound(TR-CEUS) in diagnosis of benign and malignant prostatic neoplasms.Methods Sixty patients with elevated level of serum prostate specific antigen and suspected prostate diseases were examined with transrectal uhrasound(TRUS), and TR-CEUS.The pattern and intensity of CEUS in these patients were observed;and the patients with nodules were examined with CEUS guided biopsy and sextant system biopsy after ultrasound imaging.Time-intensity curves (TIC) were drawn to calculate the parameters, and the difference between benign and malignant nodes was compared.Results All sixty prostate patients were confirmed by pathological examination.Thirty-seven patients belong to benign lesions, among them 15 patients with nodule lesion had total 20 nodules, while 22 cases had benign prostatic hyperplasia.In 23 cases of malignant lesions, 18 cases had centralized nodules and 5 cases showed diffuse pathologic changes.Benign nodes of inner gland showed a main pattern of homogenous enhancement and a clear node zone, whereas, malignant nodes displayed significant enhancement in peripheral tissue.The time to peak and accelerating time (ACT) of malignant nodes were shorter than those of benign nodes (P <0.05).There was no significance in arrival time (AT) between the two groups (P>0.05).The accordance rate of TR-CEUS in the differential diagnosis of benign and malignant prostatic lesions was higher than that of TRUS (P<0.05).In addition, the sensitivity, specificity and accurate rate of TR-CEUS were higher than those of TRUS, whereas, both misdiagnosis and missed diagnosis rate of TR-CEUS were lower than those of TRUS.Conclusions TR-CEUS has clinical value for early discovery of prostatic cancer and has higher application value to differentiate malignant from benign diseases.

Transrectal contrast enhanced ultrasound in distinguishing benign from malignant nodes of prostate / 中国医学影像技术

Objective To evaluate diagnostic value of transrectal gray scale contrast enhanced ultrasound (CEUS) in distinguishing benign from malignant nodes of prostate. Methods Thirty-three patients with 38 prostate nodes underwent real-time transrectal gray scale CEUS with SonoVue and contrast pulsed sequence (CPS). Contrast enhancement pattern of the prostate nodes were recorded and time-intensity curves (TIC) were drawn to calculate the parameters and difference between benign and malignant nodes. Results Twenty benign nodes (17 in inner gland) and 18 malignant ones (14 in external gland) were confirmed by pathology. Compared with normal peripheral zone, malignant lesions showed significantly earlier time to enhancement. The time to peak (TTP), accelerating time (ACT) and peak intensity (PI) of malignant lesions were lower than those of benign lesions (P0.05). Conclusion Of all parameters in CEUS, TTP, ACT and PI are different between prostate benign and malignant lesions, and thus contribute to discriminate prostate cancer from benign diseases.