Conifer desiccation in the 2021 NW heatwave confirms the role of hydraulic damage.

The unprecedented heatwave which hit the Pacific northwest of North America in late June-early July 2021 impacted ecosystems and communities, yet evidence for and analysis of this impact are still missing. Here we bring a unique dataset quantifying the impact on conifer trees, which are keystone species of many northwest ecosystems. Moreover, we take advantage of this exceptional event as a broad, extreme, 'field experiment' to test a fundamental theory in plant physiology and prepare our forests for a harsher future.

Structural basis of the lipid transfer mechanism of phospholipid transfer protein (PLTP).

Human phospholipid transfer protein (PLTP) mediates the transfer of phospholipids among atheroprotective high-density lipoproteins (HDL) and atherogenic low-density lipoproteins (LDL) by an unknown mechanism. Delineating this mechanism would represent the first step towards understanding PLTP-mediated lipid transfers, which may be important for treating lipoprotein abnormalities and cardiovascular disease. Here, using various electron microscopy techniques, PLTP is revealed to have a banana-shaped structure similar to cholesteryl ester transfer protein (CETP).

Lipoprotein lipase and phospholipid transfer protein overexpression in human glioma cells and their effect on cell growth, apoptosis, and migration.

Glioma is one of the common tumors in brain. The expression level of lipoprotein lipase (LPL) or phospholipid transfer protein (PLTP) may influence glioma progression and its relationship with clinical and pathological parameters. The clinical significance of LPL or PLTP expression in glioma has not been established.

Mortality reduction in patients treated with long-term intensive lipid therapy: 25-year follow-up of the Familial Atherosclerosis Treatment Study-Observational Study.

Background: Cardiovascular disease (CVD) begins early in life and is associated with both the number of risk factors present and length of exposure to these risk factors including hyperlipidemia.

Objectives: The clinical benefit of intensive lipid therapy over 25 years was investigated in the Familial Atherosclerosis Treatment Study-Observational Study.

Methods: Of 175 coronary artery disease subjects with mean low-density lipoprotein cholesterol (LDL-C) of 191 mg/dL and mean age of 50 years, who completed the randomized and placebo-controlled Familial Atherosclerosis Treatment Study, 100 chose receiving lipid management by their physicians (usual care [UC]) and 75 elected to receive an intensive treatment [IT] for lipid management with lovastatin (40 mg/d), niacin (2.

Relationship of baseline HDL subclasses, small dense LDL and LDL triglyceride to cardiovascular events in the AIM-HIGH clinical trial.

Background And Aims: Previous results of the AIM-HIGH trial showed that baseline levels of the conventional lipid parameters were not predictive of future cardiovascular (CV) outcomes. The aims of this secondary analysis were to examine the levels of cholesterol in high density lipoprotein (HDL) subclasses (HDL2-C and HDL3-C), small dense low density lipoprotein (sdLDL-C), and LDL triglyceride (LDL-TG) at baseline, as well as the relationship between these levels and CV outcomes.

Methods: Individuals with CV disease and low baseline HDL-C levels were randomized to simvastatin plus placebo or simvastatin plus extended release niacin (ERN), 1500 to 2000 mg/day, with ezetimibe added as needed in both groups to maintain an on-treatment LDL-C in the range of 40-80 mg/dL.

Lipoprotein (a) measurements for clinical application.

The high degree of size heterogeneity of apo(a), the distinct protein component of lipoprotein (a) [Lp(a)], renders the development and selection of specific antibodies directed to apo(a) more difficult and poses significant challenges to the development of immunoassays to measure its concentration in plasma or serum samples. Apo(a) is extremely variable in size not only between but also within individuals because of the presence of two different, genetically determined apo(a) isoform sizes. Therefore, the antigenic determinants per particle available to interact with the antibodies will vary in the samples and the calibrators, thus contributing to apo(a) size-dependent inaccuracy of different methods.

Inhibition of thrombin generation in human plasma by phospholipid transfer protein.

Background: Plasma phospholipid transfer protein (PLTP) transfers lipids between donors and acceptors (e.g., from HDL to VLDL) and modulates lipoprotein composition, size, and levels.

PLTP activity inversely correlates with CAAD: effects of PON1 enzyme activity and genetic variants on PLTP activity.

Recent studies have failed to demonstrate a causal cardioprotective effect of HDL cholesterol levels, shifting focus to the functional aspects of HDL. Phospholipid transfer protein (PLTP) is an HDL-associated protein involved in reverse cholesterol transport. This study sought to determine the genetic and nongenetic predictors of plasma PLTP activity (PLTPa), and separately, to determine whether PLTPa predicted carotid artery disease (CAAD).

HDL-3 is a superior predictor of carotid artery disease in a case-control cohort of 1725 participants.

Background: Recent data suggest that high-density lipoprotein cholesterol (HDL-C) levels are likely not in the causative pathway of atheroprotection, shifting focus from HDL-C to its subfractions and associated proteins. This study's goal was to determine which HDL phenotype was the better predictor of carotid artery disease (CAAD).

Methods And Results: HDL-2 and HDL-3 were measured in 1725 participants of European ancestry in a prevalent case-control cohort study of CAAD.

Cerebrospinal fluid apolipoprotein E and phospholipid transfer protein activity are reduced in multiple sclerosis; relationships with the brain MRI and CSF lipid variables.

Apolipoprotein E (apoE), phospholipid transfer protein (PLTP) activity, lipids, total tau and beta amyloid 1-42 (Aβ) were measured in cerebrospinal fluid (CSF) from controls (n=38) and multiple sclerosis (MS) patients (n=91). ApoE and PLTP activity were significantly reduced in MS compared to non-inflammatory disease controls (NINDC; p<0.05).

Lipoprotein lipase (LPL) is associated with neurite pathology and its levels are markedly reduced in the dentate gyrus of Alzheimer's disease brains.

Lipoprotein lipase (LPL) is involved in regulation of fatty acid metabolism, and facilitates cellular uptake of lipoproteins, lipids and lipid-soluble vitamins. We evaluated LPL distribution in healthy and Alzheimer's disease (AD) brain tissue and its relative levels in cerebrospinal fluid. LPL immunostaining is widely present in different neuronal subgroups, microglia, astrocytes and oligodendroglia throughout cerebrum, cerebellum and spinal cord.

Relationship of apolipoproteins A-1 and B, and lipoprotein(a) to cardiovascular outcomes: the AIM-HIGH trial (Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglyceride and Impact on Global Health Outcomes).

Objectives: This study sought to examine the relationship between baseline and on-study apolipoproteins (apo) A-1 and B and lipoprotein(a) [Lp(a)] levels and the development of subsequent cardiovascular (CV) events in the AIM-HIGH (Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglyceride and Impact on Global Health Outcomes) trial.

Background: Niacin has been reported to lower apoB and Lp(a) and to raise apoA-1.

Methods: Individuals with CV disease and low baseline levels of high-density lipoprotein cholesterol were randomized to simvastatin plus placebo or simvastatin, plus extended-release niacin ([ERN], 1,500 to 2,000 mg/day), with ezetimibe added as needed, in both groups, to maintain an on-treatment low-density lipoprotein cholesterol in the range of 40 to 80 mg/dl.

Inner retinal metabolic rate of oxygen by oxygen tension and blood flow imaging in rat.

The metabolic function of inner retinal cells relies on the availability of nutrients and oxygen that are supplied by the retinal circulation. Assessment of retinal tissue vitality and function requires knowledge of both the rate of oxygen delivery and consumption. The purpose of the current study is to report a novel technique for assessment of the inner retinal metabolic rate of oxygen (MO(2)) by combined measurements of retinal blood flow and vascular oxygen tension (PO(2)) in rat.

Linkage and association of phospholipid transfer protein activity to LASS4.

Phospholipid transfer protein activity (PLTPa) is associated with insulin levels and has been implicated in atherosclerotic disease in both mice and humans. Variation at the PLTP structural locus on chromosome 20 explains some, but not all, heritable variation in PLTPa. In order to detect quantitative trait loci (QTLs) elsewhere in the genome that affect PLTPa, we performed both oligogenic and single QTL linkage analysis on four large families (n = 227 with phenotype, n = 330 with genotype, n = 462 total), ascertained for familial combined hyperlipidemia.

Role of plasma phospholipid transfer protein in lipid and lipoprotein metabolism.

The understanding of the physiological and pathophysiological role of PLTP has greatly increased since the discovery of PLTP more than a quarter of century ago. A comprehensive review of PLTP is presented on the following topics: PLTP gene organization and structure; PLTP transfer properties; different forms of PLTP; characteristics of plasma PLTP complexes; relationship of plasma PLTP activity, mass and specific activity with lipoprotein and metabolic factors; role of PLTP in lipoprotein metabolism; PLTP and reverse cholesterol transport; insights from studies of PLTP variants; insights of PLTP from animal studies; PLTP and atherosclerosis; PLTP and signal transduction; PLTP in the brain; and PLTP in human disease. PLTP's central role in lipoprotein metabolism and lipid transport in the vascular compartment has been firmly established.

Impact of site-specific N-glycosylation on cellular secretion, activity and specific activity of the plasma phospholipid transfer protein.

The plasma phospholipid transfer protein (PLTP) plays a key role in lipid and lipoprotein metabolism. It has six potential N-glycosylation sites. To study the impact of these sites on PLTP secretion and activity, six variants containing serine to alanine point mutations were prepared by site-directed mutagenesis and expressed in Chinese hamster ovary Flp-In cells.

Lipoprotein(a) levels, apo(a) isoform size, and coronary heart disease risk in the Framingham Offspring Study.

The aim of this study was to assess the independent contributions of plasma levels of lipoprotein(a) (Lp(a)), Lp(a) cholesterol, and of apo(a) isoform size to prospective coronary heart disease (CHD) risk. Plasma Lp(a) and Lp(a) cholesterol levels, and apo(a) isoform size were measured at examination cycle 5 in subjects participating in the Framingham Offspring Study who were free of CHD. After a mean follow-up of 12.

Different phospholipid transfer protein complexes contribute to the variation in plasma PLTP specific activity.

Phospholipid transfer protein (PLTP) facilitates the transfer of phospholipids among lipoproteins. Over half of the PLTP in human plasma has been found to have little phospholipid transfer activity (inactive PLTP). We recently observed that plasma PLTP specific activity is inversely correlated with high-density lipoprotein (HDL) level and particle size in healthy adults.

Evaluation of a new homogenous method for detection of small dense LDL cholesterol: comparison with the LDL cholesterol profile obtained by density gradient ultracentrifugation.

Background: Small, dense LDL (sdLDL) are highly atherogenic, and evidence indicates that sdLDL are useful predictors of cardiovascular disease. We evaluated a homogeneous method for the quantitative determination of sdLDL cholesterol (sdLDL-C) and compared it to the LDL-cholesterol profile obtained by density gradient ultracentrifugation (DGUC).

Methods: sdLDL-C was measured in plasma and in lipoprotein fractions obtained by DGUC using the sdLDL-EX "Seiken" kit.

Phospholipid transfer protein in human plasma associates with proteins linked to immunity and inflammation.

Phospholipid transfer protein (PLTP), which associates with apolipoprotein A-I (the major HDL protein), plays a key role in lipoprotein remodeling. Because its level in plasma increases during acute inflammation, it may also play previously unsuspected roles in the innate immune system. To gain further insight into its potential physiological functions, we isolated complexes containing PLTP from plasma by immunoaffinity chromatography and determined their composition.

Association of Apo(a)isoform size with dyslipoproteinemia in male venous thrombosis patients.

Background: Lp(a) is a proatherogenic lipoprotein that may also be prothrombotic. Apo(a) size isoforms have differential effects on fibrinolysis. Whereas Lp(a) concentrations have been linked to venous thromboembolic disease (VTE) risk, apo(a) polymorphisms in VTE have not been studied.

Genetic and nongenetic sources of variation in phospholipid transfer protein activity.

Phospholipid transfer protein (PLTP) belongs to the lipid transfer/lipopolysaccharide-binding protein gene family. Expression of PLTP has been implicated in the development of atherosclerosis. We evaluated the effects of PLTP region tagging single nucleotide polymorphisms (SNPs) on the prediction of both carotid artery disease (CAAD) and PLTP activity.

Effects of combination lipid therapy on coronary stenosis progression and clinical cardiovascular events in coronary disease patients with metabolic syndrome: a combined analysis of the Familial Atherosclerosis Treatment Study (FATS), the HDL-Atherosclerosis Treatment Study (HATS), and the Armed Forces Regression Study (AFREGS).

We examined the impact of metabolic syndrome (MS) on coronary stenosis progression and major cardiovascular (CV) events and investigated the mitigating effects of low-density lipoprotein (LDL) cholesterol lowering and LDL cholesterol lowering plus high-density lipoprotein (HDL) cholesterol increasing. This analysis combined individual patient data from 445 subjects who participated in 3 double-blinded, randomized, placebo-controlled trials (FATS, HATS, and AFREGS) comparing intensive lipid therapy to placebos on coronary stenosis progression by quantitative coronary angiography and on major CV events. The primary end points were change in mean proximal coronary diameter stenosis (Delta%S(prox)) over 3 years and the frequency of the predefined composite of coronary artery disease death, nonfatal myocardial infarction, stroke, and revascularization due to worsening ischemia.