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Background: The most commonly used method for low-density lipoprotein cholesterol (LDL-C) estimation is the Friedewald equation, which has notable limitations. However, more accurate methods have been proposed. This study investigates the advantages and limitations of these methods and identifies the contexts in which each equation is the most or least applicable., Methods: A cohort of 222 individuals underwent a standard lipid profile assessment, including directly measuring their LDL-C (dLDL-C). LDL-C was also estimated using the Friedewald, Martin-Hopkins, and Sampson equations. The differences (%Delta) between the estimated and measured LDL-C were analyzed in relation to dLDL-C, high-density lipoprotein cholesterol (HDL-C), and triglyceride levels., Results: The %Delta was significantly lower ( p < 0.0001) for the Martin-Hopkins (-8.8 ± 9.8) and Sampson (-9.5 ± 9.2) equations compared to Friedewald (-12.2 ± 9.2). All equations increasingly underestimated LDL-C as the dLDL-C levels decreased. The %Delta of the Martin-Hopkins equation showed significant positive correlations with dLDL-C (≤130 mg/dL) and triglycerides and a significant negative correlation with HDL-C. In a subgroup of 30 individuals with extreme %Delta values, patterns of gross underestimation were observed, particularly when low LDL-C, low triglycerides, and high HDL-C coincided., Conclusions: The Martin-Hopkins equation is a superior method for LDL-C estimation and a valuable tool in precision medicine. However, clinicians and laboratory professionals must be aware of its limitations and recognize patterns that could lead to significant LDL-C underestimation. We propose an algorithm for clinical laboratories to provide personalized LDL-C assessments.

Biomarkers are crucial in cancer diagnostics, prognosis, and surveillance. Extensive research has been dedicated to identifying biomarkers that are broadly applicable across multiple cancer types and can be easily obtained from routine investigations such as blood cell counts. One such biomarker, the neutrophil-to-lymphocyte ratio (NLR), has been established as a prognostic marker in cancer. However, due to the dynamic nature of cancer diagnosis and treatment, periodic updates are necessary to keep abreast of the vast amount of published data. In this review, we searched the PubMed database and analyzed and synthesized recent literature (2018-February 2024) on the role of NLR in predicting clinical outcomes in nonhematologic malignancies. The search was conducted using the PubMed database. We included a total of 88 studies, encompassing 28,050 human subjects, and categorized the findings into four major groups: gastrointestinal cancer, cancers of the urinary tract and reproductive system, lung cancer, and breast cancer. Our analysis confirms that NLR is a reliable prognostic indicator in cancer, and we discuss the specific characteristics, limitations, and exceptions associated with its use. The review concludes with a concise Q&A section, presenting the most relevant take-home messages in response to five key practical questions on this topic.

Background : Matrix metalloproteinases (MMPs) play an important role in the pathophysiology of atherosclerosis. Reportedly, statins can decrease MMP activity in patients with atherosclerotic cardiovascular disease, but this effect has not been studied in healthy individuals. Methods : MMPs 2, 7, and 9 and several other parameters were measured before and after a four-week course of moderate-dose atorvastatin (20 mg/day) in 21 healthy individuals. Results : Atorvastatin treatment resulted in lower total cholesterol, LDL-cholesterol, non-HDL-cholesterol, and triglycerides ( p < 0.001 for all), but higher levels of plasma enzymes AST, ALT, CK, and LDH ( p < 0.05 for all). No effect of atorvastatin on plasma MMP median concentrations was recorded. Before treatment, moderate positive significant correlations were found between MMP-7 and age, blood lipids, and blood count-derived inflammatory markers. Pre-treatment MMP-7 was best predicted by the total cholesterol-to-HDL cholesterol ratio in a remnant cholesterol-weighted least squares regression model. After atorvastatin treatment, MMP-7 no longer correlated with these markers. Conclusions : While the effect of statins on plasma MMPs in atherosclerosis is controversial, short-term moderate-dose atorvastatin treatment does not seem to affect levels of MMPs 2, 7, and 9 in healthy individuals. However, an intriguing correlation between MMP-7 and atherosclerosis-related blood lipids and neutrophil-associated inflammatory biomarkers seems to be disrupted by atorvastatin independently of hsCRP, possibly via pleiotropic effects.