Cystatin C predicts the risk of incident cerebrovascular disease in the elderly: A meta-analysis on survival date studies.

BACKGROUND: Stroke is the third leading cause of global year of life lost in all-age and second-ranked cause of disability adjusted life years in middle-aged and elder population. Therefore, it is critical to study the relationship between vascular-related risk factors and cerebrovascular diseases. Several cross-sectional studies have shown that Cystatin C (Cys C) is an independent risk factor for cerebrovascular diseases and levels of Cys C are significantly higher in stroke patients than in healthy individuals. In this meta-analysis, we introduce a Cox proportional hazards model to evaluate the causality between Cys C and the risk of cerebrovascular accident in the elderly. METHODS: We searched PubMed, EMBASE, the Web of Science, and the Cochrane Library from 1985 to 2019 for studies on the relationship between serum Cys C and incidence stroke with Cox proportional hazards models. We conducted a subgroup analysis of the selected studies to determine a connection between atherosclerosis and stroke. Finally, 7 research studies, including 26,768 patients without a history of cerebrovascular, were studied. RESULTS: After comparing the maximum and minimum Cys C levels, the hazard ratio for all types of stroke, including ischemic and hemorrhagic stroke, was 1.18 (95% confidence interval 1.04-1.31) with moderate heterogeneity (I2 = 43.0%; P = .119) in a fixed-effect model after pooled adjustment for other potential risk factors. In the subgroup analysis, the hazard ratio and 95% confidence interval for Cys C stratified by atherosclerosis was 1.85 (0.97-2.72). As shown in Egger linear regression test, there was no distinct publication bias (P = .153). CONCLUSION: Increased serum Cys C is significantly associated with future stroke events in the elderly, especially in patients with carotid atherosclerosis. Thus, serum levels of Cys C could serve as a predicted biomarker for stroke attack.

Residual Negative Pressure in Vacuum Blood-Collection Tube and Hemolysis in Pediatric Blood Specimens.

OBJECTIVE: To determine a method to reduce specimen hemolysis rates in pediatric blood specimens. METHODS: A total of 290 blood specimens from pediatric patients were classified into the capped group or uncapped group. The hemolysis index and levels of lactate dehydrogenase (LDH) were measured using an automated biochemical analyzer. Also, we performed a paired test to measure the concentration of free hemoglobin in specimens from 25 randomly selected healthy adult volunteers, using a direct spectrophotometric technique. RESULTS: The hemolytic rate of capped specimens was 2-fold higher than that of uncapped specimens. We found significant differences for LDH. Also, there was a significant difference in the concentration of free hemoglobin in the random-volunteers test. CONCLUSIONS: Eliminating the residual negative pressure of vacuum blood-collection tubes was effective at reducing the macrohemolysis and/or microhemolysis rate.

Residual Negative Pressure in Vacuum Tubes Might Increase the Risk of Spurious Hemolysis.

BACKGROUND: We planned a study to establish whether spurious hemolysis may occur when negative pressure remains in vacuum tubes. METHODS: Four tubes with different vacuum levels (-54, -65, -74, and -86 kPa) were used to examine blood drawn from one healthy volunteer; the tubes were allowed to stand for different times (1, 2, 3, and 4 hours). The plasma was separated and immediately tested for free hemoglobin (FHb). Thirty patients were enrolled in a verification experiment. RESULTS: The degree of hemolysis observed was greater when the remaining negative pressure was higher. Significant differences were recorded in the verification experiment. CONCLUSIONS: The results suggest that residual negative pressure might increase the risk of spurious hemolysis.

Bioinspired multifunctional hetero-hierarchical micro/nanostructure tetragonal array with self-cleaning, anticorrosion, and concentrators for the SERS detection.

Heterohierarchical micro/nanostructure tetragonal array consisted of engineering materials of microprotrusion-like Cu and secondary nanostructured dendrite Ag have been fabricated via a primary cell-induced deposition and a facile galvanic displacement reaction combined with photolithography technique on Cu foil. Confined by the circle microwell tetragonal array of the photoresist template, regular microprotrusion-like Cu with the tunable size of diameter can be easily deposited on the surface of Cu foil. Then, the secondary dendritic Ag nanostructures in situ grow on the surface of microprotrusion via a galvanic displacement reaction, leading to the formation of heterohierarchical micro/nanostructure tetragonal array, which is similar to the surface microstructure of the lotus leaf. Inspired by this novel surface structure of imitating lotus leaf, its wettability has been systematically investigated. The results indicate that the fabricated heterohierarchical micro/nanostructure regular array after the surface fluoration presents a remarkable superhydrophobic performance. Initiated from its superhydrophobicity, an excellent self-cleaning property has also been demonstrated. In addition, the durability of the superhydrophobic surfaces is examined in the wide pH range of corrosive liquids. Notably, the fabricated superhydrophobic surface can be potentially used as concentrators, which presents a great perspective in the field of analysis through employing the SERS detection as an example.

[Determination of trace free copper and zinc in serum samples by graphite furnace atomic absorption spectrometry after two-step precipitation of protein].

A method was developed for the determination of trace free copper and zinc in serum sample by GFAAS after two-step precipitation. The serum and ethanol were mixed with volume ratio of 1 : 2. The mixture was subsequently denatured at 70 degrees C and centrifuged to precipitate proteins. The determination, limit of copper (3sigma) was 1.2 microg x L(-1) and the recovery was 92.3% - 104%, and the determination. Limit of zinc(3sigma) was 0.098 microg x L(-1) and the recovery was 90%-107%. This two-step precipitation method can be used to determine non-protein-bound copper in tumor patients and healthy people.