Figure 2 - uploaded by Alessandro De Stefano
Content may be subject to copyright.
Hook effect evaluation of the lipoprotein-associated phospholipase A2 activity assay on the Dimension Vista analyser. Substrate depletion hooks back measured ODs only at recombinant lipoprotein-associated phospholipase A2 (Lp-PLA 2 ) activities > 1000 U/L.
Source publication
Introduction
Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a marker of vascular inflammation associated with coronary heart disease and stroke. We evaluated analytical performance of the PLAC® Activity Test on Siemens Dimension Vista® 1500 analyzer and measured Lp-PLA2 activity in Italian adults to establish reference intervals (RIs) and eva...
Context in source publication
Citations
... Na osnovu dosadašnjih ispitivanja procenjeno je da je Lp-PLA2 novi inflamatorni biomarker koji predviđa rizik od kardiovaskularnih bolesti i tromboza, nezavisan od učestalih (LDL-C, krvni pritisak, pušenje) i novih (C-reaktivni protein, CRP) faktora rizika (13). Studije koje su ispitivale vrednosti Lp-PLA2 uglavnom su analizirale populacije sa specifičnim stanjima, a svega nekoliko je ispitivalo vrednosti ovog enzima u zdravoj populaciji (14,15). ...
... Značajan uticaj su imali i hormonski status ispitanica i ulazak u postmenopauzu. Prema rezultatima ispitivanja različitih studija ustanovljeno je da je veća aktivnost Lp-PLA2 povezana sa rizikom od kardiovaskularnih bolesti u sledećim podgrupama: starost < 60 godina, procenat muških pojedinaca > 50% i praćenje < 10 godina (14). Rezultati ove studije nisu pokazali značajnu razliku u odnosu na starost ispitanika, ali je granična starost u ovom ispitivanju bila 50 godina. ...
Introduction: Lipoprotein-associated Phospholipase A2 (Lp-PLA2) is an essential mediator of inflammation, which has a vital role in inflammatory diseases of the vascular system. It has a significant role in the occurrence of thrombosis, the main manifestation of antiphospholipid syndrome. Aim: To investigate the values of Lp-PLA2 in patients with antiphospholipid syndrome (APS) regarding the distribution of all data, age, gender, disease duration, and type of disease. Material and methods: This experimental work analyzed samples of 74 patients diagnosed with APS. Concentrations of Lp-PLA2 were determined by ELISA (Enzyme-Linked Immunosorbent Assay) method. Results: The activity of Lp-PLA2 was higher than the recommended referent values. There is no significant difference in the values of Lp-PLA2 concerning patients' age, gender, disease duration, and type of disease (p > 0,05). There was a statistically significant correlation between the patients' age and the disease duration (rho = 0.359; p = 0.002). Conclusion: Elevated values of Lp-PLA2, so as the correlation between the years of age and duration of APS can be important information to doctors in the appropriate treatment of these patients. It is up to future prospective studies to confirm the significance of Lp-PLA2 determination in patients with APS.
... Comparisons of the association of Lp-PLA 2 mass and activity in the same materials revealed correlation coefficients ranging from 0.36 to 0.86 and that the accuracy in predicting the risks of 3 Cardiovascular Therapeutics CVD and ischemic stroke was greater for Lp-PLA 2 activity than for Lp-PLA 2 concentration [41][42][43][44]. The risk of CHD and ischemic stroke is approximately 2.1-fold higher in people with PLAC activity over 225 nmol/min/mL than with PLAC activity less than 225 nmol/min/mL [45]. ...
Ischemic stroke, which occurs following blockage of the blood supply to the brain, is a leading cause of death worldwide. Its main cause is atherosclerosis, a disease of the arteries characterized by the deposition of plaques of fatty material on the inner artery walls. Multiple proteins involved in the inflammation response have been identified as diagnosing biomarkers of ischemic stroke. One of these is lipoprotein-associated phospholipase A2 (Lp-PLA2), an enzyme that can hydrolyze circulating oxidized phospholipids, generating proinflammatory lysophosphatidylcholine and promoting the development of atherosclerosis. In the last two decades, a number of studies have revealed that both the concentration and the activity of Lp-PLA2 are independent biomarkers of ischemic stroke. The US Food and Drug Administration (FDA) has approved two tests to determine Lp-PLA2 mass and activity for predicting stroke. In this review, we summarize the biological properties of Lp-PLA2, the detection sensitivity and limitations of Lp-PLA2 measurement, the clinical significance and association of Lp-PLA2 in ischemic stroke, and the prospects of therapeutic inhibition of Lp-PLA2 as an intervention and treatment.
... Atherosclerosis is a vascular disease of the coronary arteries and the peripheral and cerebrovascular vasculature. The hallmarks of atherosclerosis include accumulation of lipids, cell proliferation and migration, inflammation, and NO reduction that leads to endothelial dysfunction [96]. The anti-inflammatory effects of luteolin as well as its inhibition properties on both cell proliferation and migration were reported in several studies. ...
Flavonoids are interesting molecules synthetized by plants. They can be found abundantly in seeds and fruits, determining the color, flavor, and other organoleptic characteristics, as well as contributing to important nutritional aspects. Beyond these characteristics, due to their biochemical properties and characteristics, they can be considered bioactive compounds. Several interesting studies have demonstrated their biological activity in different cellular and physiological processes in high-order organisms including humans. The flavonoid molecular structure confers the capability of reacting with and neutralizing reactive oxygen species (ROS), behaving as scavengers in all processes generating this class of molecules, such as UV irradiation, a process widely present in plant physiology. Importantly, the recent scientific literature has demonstrated that flavonoids, in human physiology, are active compounds acting not only as scavengers but also with the important role of counteracting the inflammation process. Among the wide variety of flavonoid molecules, significant results have been shown by investigating the role of the flavones luteolin and luteolin-7-O-glucoside (LUT-7G). For these compounds, experimental results demonstrated an interesting anti-inflammatory action, both in vitro and in vivo, in the interaction with JAK/STAT3, NF-κB, and other pathways described in this review. We also describe the effects in metabolic pathways connected with inflammation, such as cellular glycolysis, diabetes, lipid peroxidation, and effects in cancer cells. Moreover, the inhibition of inflammatory pathway in endothelial tissue, as well as the NLRP3 inflammasome assembly, demonstrates a key role in the progression of such phenomena. Since these micronutrient molecules can be obtained from food, their biochemical properties open new perspectives with respect to the long-term health status of healthy individuals, as well as their use as a coadjutant treatment in specific diseases.
... Lp-PLA 2 has been identified as an independent predictor of cardiovascular disease (CVD),and has been recommended as an adjunct to traditional risk assessment in patients with moderate and high 10-year risk of CVD as defined by Framingham risk scores [28]. In the REGARDS study, Lp-PLA 2 activity was associated with coronary heart disease (CHD) risk over 5.3 years based on Cox proportional hazards regression [29]. Our study found that in the CSF group, with the increase in TFC, Lp-PLA2 levels exhibited an increasing trend, and there was a significant positive correlation between CSF and Lp-PLA 2 . ...
Objective:
Coronary slow flow (CSF) is characterized by delayed opacification of distal epicardial coronary arteries without significant coronary stenosis. In addition, The changes of lipoprotein-associated phospholipase A2 (Lp-PLA2) as a significant predictive factor for CSF remain controversial. The study aims to investigate the association between plasma Lp-PLA2 and CSF.
Methods:
In this retrospective study, 170 consecutive patients who underwent coronary angiography were enrolled in Beijing Anzhen Hospital from January 2017 to September 2019, and were divided into CSF group and normal control groups. According to coronary blood flow rate measured by the thrombolysis in myocardial infarction frame count (TFC) method, CSF was defined as TFC > 27. Serum Lp-PLA2 levels were measured in an enzyme-linked immunosorbent assay.
Results:
Lp-PLA2 levels were higher in the CSF group than in the control group (288.6 ± 50.3 versus 141.9 ± 49.7, P < 0.001) and were significantly correlated with the mean coronary artery thrombolysis in myocardial infarction (TIMI) frame count (r = 0.790, P<0.001). Logistic regression analysis showed that high Lp-PLA2 was independently associated with CSF after adjustment for conventional risk factors (OR = 1.040, CI = 1.022-1.059, P<0.001). Male sex (OR = 2.192, CI = 1.161-4.140, P = 0.016) and hypertension (OR = 1.965, CI = 1.034-3.736, P = 0.039) were also CSF risk factors. Receiver-operating characteristic curve (ROC) analysis showed that Lp-PLA2 levels can predict CSF severity; the predictive power was higher than the other risk factors.
Conclusion:
Our study demonstrated that patients with CSF had higher circulating levels of Lp-PLA2 than normal controls. After adjustment for potential confounders, increased Lp-PLA2 was independently associated with presence of CSF.
... The PLAC ® Test Activity Kit has been validated on different automatic clinical chemistry analyzers, to encourage the method harmonization process for Lp-PLA 2 activity assessment, method standardization and to increase the concordance between assays. 6 Manufacturer declared a cut point at 225 nmol/min/mL which identifies high cardiovascular risk patients. Universal clinically appropriate cut-points for Lp-PLA 2 activity are needed to improve the assessment of cardiovascular risk. ...
Metabolic diseases are chronic disorders correlated to a greater risk of cardiovascular event and death. Recently, many data have sustained the biological link between microvascular dysfunction, oxidative stress, vascular inflammation, and metabolic diseases. The determination of new and specific blood biomarkers of vascular inflammation associated with obesity-related metabolic syndrome (MetS) and diabetes such as lipoprotein-associated phospholipase A2 (Lp-PLA2) could be useful to identify subject with high risk of cardiovascular events. Lp-PLA2 participates by a crucial role in microvascular dysfunction and oxidative stress showing positive association with metabolic disorders. In this review, we will argue the evolving role of Lp-PLA2 in predicting cardiovascular events in metabolic disease patients.
... 12 The Lp-PLA2 activity reagent PLAC (Diazyme) was the first reagent approved by the Food and Drug Administration (FDA) in December in 2014, and its performance has been verified by studies in 2016 and 2017. 12,13 Alternatively, Diasys was the first Lp-PLA2 activity reagents registered by the China Food and Drug Administration, and several studies have shown an association between CVD and Lp-PLA2 activity using this reagent. Furthermore, in addition to Diasys, our team has also validated the performance of Zybio, Hengxiao, and Evermed Lp-PLA2 reagents for activity testing. ...
Background
Lp‐PLA2 is a novel inflammation marker in cardiovascular disease. While several manufactures have registered Lp‐PLA2 activity reagents, few studies have investigated the consistency among these assays. In this study, we compared and recalibrated Lp‐PLA2 activity assays.
Methods
Serum samples from 110 patients and 140 healthy individuals were collected for method comparison and reference interval validation, respectively. Fresh human serum pools (847 and 442 U/L) were used for recalibration. Lp‐PLA2 activity was analyzed using all five assays with a Beckman AU 5800 analyzer. Passing‐Bablok regression equations and Bland‐Altman plots were used to estimate the relationship and bias among the results. A 2.5% confidence interval (CI) and 97.5% CI were used to establish a laboratory reference interval.
Results
Assay imprecision varied from 0.8%‐2.9%, while the overall coincidence rates ranged from 75.5%‐98.2%. Passing‐Bablok regression shows excellent linear correlation between Evermed and Diasys (R2 = 0.999), while that between Diazyme and Evermed was poor (R2 = 0.846). The R² and correlation coefficient r among assays were 0.846‐0.999 and 0.8947‐0.9993, respectively. The mean bias percentages ranged from −71.5%‐1.6% and −2.0%‐11.6% before and after recalibration. As Diazyme and Diasys were not comparable, the Diazyme assay was not recalibrated. The reference intervals determined for Diasys, Evermed, Hengxiao, and Zybio were 184‐605, 208‐704, 81‐328, and 273‐696 U/L, respectively.
Conclusions
Our results indicate that recalibration increased assay agreement and also highlight the need for each laboratory to establish its own reference interval for Lp‐PLA2 activity.
Odkaz príslušníka generácie, ktorá zažila - a užila si - prvý novoročný prejav pána prezidenta Václava Havla s pamätným výrokom „Tato země nevzkvétá.“ príslušníkom generácie, ktorá sa narodila po tomto prejave:
Ruka v ruke so zdravotníctvom a (masovým) lekárskym klinickým výskumom na slovenských lekárskych fakultách aj úroveň našich časopiseckých vedeckých publikácií naďalej upadá.
Ostatne, obdobne ako aj veľká časť zahraničného klinického výskumu, hodnotená podľa jeho výstupov, vedeckých publikácií. Serióznych vedeckých rozborov, prečo je tomu tak, je – na úrovni Slovenska, Česka aj celosvetovo – dosť. Dôsledkom tejto situácie je potom nedávno popísaná úvaha (1). Nereprodukovateľnosť vedeckého výskumu, prezentovaného publikáciami, je všeobecne uznávaným problémom, ktorý poškodzuje vedecký pokrok. Dosah nereprodukovateľnosti bol v tejto úvahe v onkologickej terminológii rozdelený na benígnu, pre-malígnu a malígnu. Benígna je v nízko impaktových článkoch, publikovaných nízko impaktovými autormi v nízko impaktových časopisoch (s impakt faktorom menej ako 2). Premalígna je v stredne impaktových článkoch, publikovaných stredne impaktovými autormi v stredne impaktových časopisoch (s impakt faktorom 2 až 5). Malígna, najnebezpečnejšia, je spojená so zrejme vysokoimpaktovými publikáciami, publikovanými vysoko impaktovými autormi vo vysoko impaktových časopisoch najvyššej úrovne.
Toto rozdelenie môže byť nami, v našich lokálnych časopisoch po slovensky publikujúcimi autormi vnímané dvojako:
Je fajn, že naše publikácie nikto nečíta a nikto mimo nášho jazykového priestoru necituje. Nemôžu vedeckému pokroku uškodiť. (Sarkazmus.)
Je to doklad toho, že naše publikácie netreba čítať a ani citovať, napriek úpenlivým upozorneniam až prosbám redakcií našich časopisov. (Realita... ?)
Pri čítaní článkov s kardiologickým a neurologickým zameraním som v ostatných 2 rokoch natrafil, popri veľkom počte dobre spracovaných, na viacero takých, s ktorých obsahom a/alebo niektorými závermi, ako nereprodukovateľnými, nesúhlasím. V tejto publikácii sú uvedené fotoreprodukcie niektorých z nich a vo forme Dopisu redakcii - ktorý je raz reálny a v ostatných prípadoch fiktívny - poznámky, pripomienky, zdôvodnenia toho, čo v nich pokladám za nekorektné.
Mojim zámerom je primäť čitateľa ku čítaniu odborného textu s porozumením. Čitateľ nech si sám urobí obraz o pôvodnom texte článkov a o výhradách ku nemu.
