In spite of the great progress that has been made towards automating brain extraction in human magnetic resonance imaging (MRI), challenges remain in the automation of this task for mouse models of brain disorders. Researchers often resort to editing brain segmentation results manually when automated methods fail to produce accurate delineations. However, manual corrections can be labor-intensive and introduce interrater variability.
View Article and Find Full Text PDFPhosphatidylserine (PS) is an important anionic phospholipid that is synthesized within the endoplasmic reticulum (ER). While PS shows the highest enrichment and serves important functional roles in the plasma membrane (PM) but its role in the nucleus is poorly explored. Using three orthogonal approaches, we found that PS is also uniquely enriched in the inner nuclear membrane (INM) and the nuclear reticulum (NR).
View Article and Find Full Text PDFPhosphatidylinositol (PI) is the precursor lipid for the minor phosphoinositides (PPIns), which are critical for multiple functions in all eukaryotic cells. It is poorly understood how phosphatidylinositol, which is synthesized in the ER, reaches those membranes where PPIns are formed. Here, we used VT01454, a recently identified inhibitor of class I PI transfer proteins (PITPs), to unravel their roles in lipid metabolism, and solved the structure of inhibitor-bound PITPNA to gain insight into the mode of inhibition.
View Article and Find Full Text PDFPrevious studies have shown that fully vaccinated patients with SARS-CoV-2 Delta variants has shorter viable viral shedding period compared to unvaccinated or partially vaccinated patients. However, data about effects of vaccination against the viable viral shedding period in patients with SARS-CoV-2 Omicron variants were limited. We compared the viable viral shedding period of SARS-CoV-2 omicron variant regard to vaccination status.
View Article and Find Full Text PDFThere has been a concerted effort by the neuroimaging community to establish standards for computational methods for data analysis that promote reproducibility and portability. In particular, the Brain Imaging Data Structure (BIDS) specifies a standard for storing imaging data, and the related BIDS App methodology provides a standard for implementing containerized processing environments that include all necessary dependencies to process BIDS datasets using image processing workflows. We present the BrainSuite BIDS App, which encapsulates the core MRI processing functionality of BrainSuite within the BIDS App framework.
View Article and Find Full Text PDFCholesterol (Chol) is an essential component of all eukaryotic cell membranes that affects the function of numerous peripheral as well as integral membrane proteins. Chol is synthesized in the ER, but it is selectively enriched within the plasma membrane (PM) and other endomembranes, which requires Chol to cross the aqueous phase of the cytoplasm. In addition to the classical vesicular trafficking pathways that are known to facilitate the bulk transport of membrane intermediates, Chol is also transported via non-vesicular lipid transfer proteins that work primarily within specialized membrane contact sites.
View Article and Find Full Text PDFPaired associative stimulation (PAS) is a widely used noninvasive brain stimulation protocol to assess neural plasticity. Its reproducibility, however, has been rarely tested and with mixed results. With two consecutive studies, we aimed to provide further tests and a more systematic assessment of PAS reproducibility.
View Article and Find Full Text PDFThe ER-resident proteins STIM1 together with the plasma membrane (PM)-localized Orai1 channels constitute the molecular components of the store-operated Ca entry (SOCE) pathway. Prepositioning of STIM1 to the peripheral ER close to the PM ensures its efficient interaction with Orai1 upon a decrease in the ER luminal Ca concentration. The C-terminal polybasic domain of STIM1 has been identified as mediating the interaction with PM phosphoinositides and hence positions the molecule to ER-PM contact sites.
View Article and Find Full Text PDFPhosphoinositide lipids (PPIn) are enriched in stearic- and arachidonic acids (38:4) but how this enrichment is established and maintained during phospholipase C (PLC) activation is unknown. Here we show that the metabolic fate of newly synthesized phosphatidic acid (PA), the lipid precursor of phosphatidylinositol (PI), is influenced by the fatty acyl-CoA used with preferential routing of the arachidonoyl-enriched species toward PI synthesis. Furthermore, during agonist stimulation the unsaturated forms of PI(4,5P) are replenished significantly faster than the more saturated ones, suggesting a favored recycling of the unsaturated forms of the PLC-generated hydrolytic products.
View Article and Find Full Text PDFThe literature on perceived novelty and product evaluation has diverged into two disparate streams of research. The first stream builds on theories of curiosity and argues that the perceived novelty of a new product benefits product evaluation because it induces curiosity and provides evaluators (e.g.
View Article and Find Full Text PDFObjective: Post-traumatic posterolateral rotatory instability (PLRI) can be shown as radiocapitellar incongruity or posterior translation (PT) of the radial head in magnetic resonance imaging (MRI). We aimed to evaluate whether PT correlated with pathologic changes of lateral elbow stabilizers in patients with lateral epicondylitis.
Materials And Methods: In MRIs of 160 patients with lateral epicondylitis, we measured PT of the radial head in the sagittal images.
Objective: To intraindividually compare hepatocellular carcinoma (HCC) washout between MRIs using hepatobiliary agent (HBA) and extracellular agent (ECA).
Materials And Methods: This study included 114 prospectively enrolled patients with chronic liver disease (mean age, 55 ± 9 years; 94 men) who underwent both HBA-MRI and ECA-MRI before surgical resection for HCC between November 2016 and May 2019. For 114 HCCs, the lesion-to-liver visual signal intensity ratio (SIR) using a 5-point scale (-2 to +2) was evaluated in each phase.
Better understanding myelination of peripheral nerves would benefit patients affected by peripheral neuropathies, including Charcot-Marie-Tooth disease. Little is known about the role the Golgi compartment plays in Schwann cell (SC) functions. Here, we studied the role of Golgi in myelination of peripheral nerves in mice through SC-specific genetic inactivation of phosphatidylinositol 4-kinase beta (PI4KB), a Golgi-associated lipid kinase.
View Article and Find Full Text PDFCurr Opin Physiol
October 2020
Calcium (Ca) ions are critically important in orchestrating countless regulatory processes in eukaryotic cells. Consequently, cells tightly control cytoplasmic Ca concentrations using a complex array of Ca-selective ion channels, transporters, and signaling effectors. Ca transport through various cellular membranes is highly dependent on the intrinsic properties of specific membrane compartments and conversely, local Ca changes have profound effects on the membrane lipid composition of such membrane sub-domains.
View Article and Find Full Text PDFDistal radius fractures (DRFs) are one of the most common fractures seen in elderly people. Patients with DRFs have a high incidence of osteoporosis and an increased risk of subsequent fractures, subtle early physical performance changes, and a high prevalence of sarcopenia. Since DRFs typically occur earlier than vertebral or hip fractures, they reflect early changes of the bone and muscle frailty and provide physicians with an opportunity to prevent progression of frailty and secondary fractures.
View Article and Find Full Text PDFOxysterol-binding protein (OSBP)-related proteins (ORPs) mediate non-vesicular lipid transfer between intracellular membranes. Phosphoinositide (PI) gradients play important roles in the ability of OSBP and some ORPs to transfer cholesterol and phosphatidylserine between the endoplasmic reticulum (ER) and other organelle membranes. Here, we show that plasma membrane (PM) association of ORP3 (also known as OSBPL3), a poorly characterized ORP family member, is triggered by protein kinase C (PKC) activation, especially when combined with Ca increases, and is determined by both PI(4,5) and PI4 After activation, ORP3 efficiently extracts PI4 and to a lesser extent phosphatidic acid from the PM, and slightly increases PM cholesterol levels.
View Article and Find Full Text PDFBackground: Although the incidence of tuberculosis (TB) is decreasing, cases of multidrug-resistant (MDR) TB and extensively drug-resistant (XDR) TB continue to increase. As conventional phenotype drug susceptibility testing (pDST) takes six to eight weeks, molecular assays are widely used to determine drug resistance. we developed QuantaMatrix Multiplexed Assay Platform (QMAP) MDR/XDR assay (QuantaMatrix Inc.
View Article and Find Full Text PDFAmong the structural phospholipids that form the bulk of eukaryotic cell membranes, phosphatidylinositol (PtdIns) is unique in that it also serves as the common precursor for low-abundance regulatory lipids, collectively referred to as polyphosphoinositides (PPIn). The metabolic turnover of PPIn species has received immense attention because of the essential functions of these lipids as universal regulators of membrane biology and their dysregulation in numerous human pathologies. The diverse functions of PPIn lipids occur, in part, by orchestrating the spatial organization and conformational dynamics of peripheral or integral membrane proteins within defined subcellular compartments.
View Article and Find Full Text PDFAnnu Rev Cell Dev Biol
October 2019
Phospholipids are synthesized primarily within the endoplasmic reticulum and are subsequently distributed to various subcellular membranes to maintain the unique lipid composition of specific organelles. As a result, in most cases, the steady-state localization of membrane phospholipids does not match their site of synthesis. This raises the question of how diverse lipid species reach their final membrane destinations and what molecular processes provide the energy to maintain the lipid gradients that exist between various membrane compartments.
View Article and Find Full Text PDFKnowledge on basic characteristics of Mycobacterium tuberculosis (MTB) is helpful to understand the disease epidemiology and support the prediction of clinical outcome of the disease. The aim of this study was to detect the genotypes and genotypic characters of clinical Mycobacterium tuberculosis (MTB) isolates from new and retreatment rifampicin-resistant patients using three different genotyping methods. Mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) typing was used to determine the diversity of 222 clinical isolates.
View Article and Find Full Text PDFThe small GTPase Rab7 is a key organizer of receptor sorting and lysosomal degradation by recruiting of a variety of effectors depending on its GDP/GTP-bound state. However, molecular mechanisms that trigger Rab7 inactivation remain elusive. Here we find that, among the endosomal pools, Rab7-positive compartments possess the highest level of PI4P, which is primarily produced by PI4K2A kinase.
View Article and Find Full Text PDFRecent evidence suggests the aging process is accelerated by HIV. Degradation of white matter (WM) has been independently associated with HIV and healthy aging. Thus, WM may be vulnerable to joint effects of HIV and aging.
View Article and Find Full Text PDFRapid detection of drug-resistant tuberculosis (DR-TB) is crucial for timely treatment and management. The GenoType MTBDR and MTBDR (MTBDR) assays have been endorsed by the World Health Organization (WHO) for the detection of DR-TB. However, MTBDR assays cannot simultaneously detect multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB).
View Article and Find Full Text PDFBiochim Biophys Acta Mol Cell Biol Lipids
January 2020