ABSTRACT
Many mammals can temporally uncouple conception from parturition by pacing down their development around the blastocyst stage. In mice, this dormant state is achieved by decreasing the activity of the growth-regulating mTOR signaling pathway. It is unknown whether this ability is conserved in mammals in general and in humans in particular. Here, we show that decreasing the activity of the mTOR signaling pathway induces human pluripotent stem cells (hPSCs) and blastoids to enter a dormant state with limited proliferation, developmental progression, and capacity to attach to endometrial cells. These in vitro assays show that, similar to other species, the ability to enter dormancy is active in human cells around the blastocyst stage and is reversible at both functional and molecular levels. The pacing of human blastocyst development has potential implications for reproductive therapies.
ABSTRACT
Speech, as the spoken form of language, is fundamental for human communication. The phenomenon of covert inner speech implies functional independence of speech content and motor production. However, it remains unclear how a flexible mapping between speech content and production is achieved on the neural level. To address this, we recorded magnetoencephalography in humans performing a rule-based vocalization task. On each trial, vocalization content (one of two vowels) and production form (overt or covert) were instructed independently. Using multivariate pattern analysis, we found robust neural information about vocalization content and production, mostly originating from speech areas of the left hemisphere. Production signals dynamically transformed upon presentation of the content cue, whereas content signals remained largely stable throughout the trial. In sum, our results show dissociable neural representations of vocalization content and production in the human brain and provide insights into the neural dynamics underlying human vocalization.
Subject(s)
Brain , Speech Perception , Humans , Speech , Magnetoencephalography/methods , Brain MappingABSTRACT
BACKGROUND: Lipoprotein(a) is a risk factor for cardiovascular events and modifies the benefit of PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors. Lipoprotein(a) concentration can be measured with immunoassays reporting mass or molar concentration or a reference measurement system using mass spectrometry. Whether the relationships between lipoprotein(a) concentrations and cardiovascular events in a high-risk cohort differ across lipoprotein(a) methods is unknown. We compared the prognostic and predictive value of these types of lipoprotein(a) tests for major adverse cardiovascular events (MACE). METHODS: The ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) compared the PCSK9 inhibitor alirocumab with placebo in patients with recent acute coronary syndrome. We compared risk of a MACE in the placebo group and MACE risk reduction with alirocumab according to baseline lipoprotein(a) concentration measured by Siemens N-latex nephelometric immunoassay (IA-mass; mg/dL), Roche Tina-Quant turbidimetric immunoassay (IA-molar; nmol/L), and a noncommercial mass spectrometry-based test (MS; nmol/L). Lipoprotein(a) values were transformed into percentiles for comparative modeling. Natural cubic splines estimated continuous relationships between baseline lipoprotein(a) and outcomes in each treatment group. Event rates were also determined across baseline lipoprotein(a) quartiles defined by each assay. RESULTS: Among 11 970 trial participants with results from all 3 tests, baseline median (Q1, Q3) lipoprotein(a) concentrations were 21.8 (6.9, 60.0) mg/dL, 45.0 (13.2, 153.8) nmol/L, and 42.2 (14.3, 143.1) nmol/L for IA-mass, IA-molar, and MS, respectively. The strongest correlation was between IA-molar and MS (r=0.990), with nominally weaker correlations between IA-mass and MS (r=0.967) and IA-mass and IA-molar (r=0.972). Relationships of lipoprotein(a) with MACE risk in the placebo group were nearly identical with each test, with estimated cumulative incidences differing by ≤0.4% across lipoprotein(a) percentiles, and all were incrementally prognostic after accounting for low-density lipoprotein cholesterol levels (all spline P≤0.0003). Predicted alirocumab treatment effects were also nearly identical for each of the 3 tests, with estimated treatment hazard ratios differing by ≤0.07 between tests across percentiles and nominally less relative risk reduction by alirocumab at lower percentiles for all 3 tests. Absolute risk reduction with alirocumab increased with increasing lipoprotein(a) measured by each test, with significant linear trends across quartiles. CONCLUSIONS: In patients with recent acute coronary syndrome, 3 lipoprotein(a) tests were similarly prognostic for MACE in the placebo group and predictive of MACE reductions with alirocumab at the cohort level. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01663402.
Subject(s)
Acute Coronary Syndrome , Anticholesteremic Agents , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Humans , Proprotein Convertase 9 , Cholesterol, LDL , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/drug therapy , Acute Coronary Syndrome/epidemiology , Lipoprotein(a) , Treatment Outcome , Anticholesteremic Agents/therapeutic use , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic useABSTRACT
HIV-1 has a broad range of nuanced interactions with the immune system, and the incorporation of cellular proteins by nascent virions continues to redefine our understanding of the virus-host relationship. Proteins located at the sites of viral egress can be selectively incorporated into the HIV-1 envelope, imparting new functions and phenotypes onto virions, and impacting viral spread and disease. Using virion capture assays and western blot, we show that HIV-1 can incorporate the myeloid antigen CD14 into its viral envelope. Virion-incorporated CD14 remained biologically active and able to bind its natural ligand, bacterial lipopolysaccharide (LPS), as demonstrated by flow virometry and immunoprecipitation assays. Using a Toll-like receptor 4 (TLR4) reporter cell line, we also demonstrated that virions with bound LPS can trigger TLR4 signaling to activate transcription factors that regulate inflammatory gene expression. Complementary assays with THP-1 monocytes demonstrated enhanced secretion of inflammatory cytokines like tumor necrosis factor alpha (TNF-α) and the C-C chemokine ligand 5 (CCL5), when exposed to LPS-loaded virus. These data highlight a new type of interplay between HIV-1 and the myeloid cell compartment, a previously well-established cellular contributor to HIV-1 pathogenesis and inflammation. Persistent gut inflammation is a hallmark of chronic HIV-1 infection, and contributing to this effect is the translocation of microbes across the gut epithelium. Our data herein provide proof of principle that virion-incorporated CD14 could be a novel mechanism through which HIV-1 can drive chronic inflammation, facilitated by HIV-1 particles binding bacterial LPS and initiating inflammatory signaling in TLR4-expressing cells.IMPORTANCEHIV-1 establishes a lifelong infection accompanied by numerous immunological changes. Inflammation of the gut epithelia, exacerbated by the loss of mucosal T cells and cytokine dysregulation, persists during HIV-1 infection. Feeding back into this loop of inflammation is the translocation of intestinal microbes across the gut epithelia, resulting in the systemic dissemination of bacterial antigens, like lipopolysaccharide (LPS). Our group previously demonstrated that the LPS receptor, CD14, can be readily incorporated by HIV-1 particles, supporting previous clinical observations of viruses derived from patient plasma. We now show that CD14 can be incorporated by several primary HIV-1 isolates and that this virion-incorporated CD14 can remain functional, enabling HIV-1 to bind to LPS. This subsequently allowed CD14+ virions to transfer LPS to monocytic cells, eliciting pro-inflammatory signaling and cytokine secretion. We posit here that virion-incorporated CD14 is a potential contributor to the dysregulated immune responses present in the setting of HIV-1 infection.
Subject(s)
HIV Infections , HIV-1 , Lipopolysaccharide Receptors , Lipopolysaccharides , Virion , Humans , Chemokine CCL5/metabolism , HIV Infections/virology , HIV Infections/immunology , HIV Infections/metabolism , HIV-1/immunology , HIV-1/physiology , Lipopolysaccharide Receptors/metabolism , Lipopolysaccharides/metabolism , Monocytes/metabolism , Monocytes/immunology , Monocytes/virology , Signal Transduction , THP-1 Cells , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alpha/metabolism , Virion/metabolismABSTRACT
Histotripsy is a relatively new therapeutic ultrasound technology to mechanically liquefy tissue into subcellular debris using high-amplitude focused ultrasound pulses. In contrast to conventional high-intensity focused ultrasound thermal therapy, histotripsy has specific clinical advantages: the capacity for real-time monitoring using ultrasound imaging, diminished heat sink effects resulting in lesions with sharp margins, effective removal of the treated tissue, a tissue-selective feature to preserve crucial structures, and immunostimulation. The technology is being evaluated in small and large animal models for treating cancer, thrombosis, hematomas, abscesses, and biofilms; enhancing tumor-specific immune response; and neurological applications. Histotripsy has been recently approved by the US Food and Drug Administration to treat liver tumors, with clinical trials undertaken for benign prostatic hyperplasia and renal tumors. This review outlines the physical principles of various types of histotripsy; presents major parameters of the technology and corresponding hardware and software, imaging methods, and bioeffects; and discusses the most promising preclinical and clinical applications.
Subject(s)
High-Intensity Focused Ultrasound Ablation , Humans , Animals , High-Intensity Focused Ultrasound Ablation/methods , Male , Neoplasms/therapy , Neoplasms/diagnostic imaging , Equipment Design , Liver Neoplasms/therapy , Liver Neoplasms/diagnostic imagingABSTRACT
Advanced glycation endproducts (AGEs) contribute to cellular damage of various pathologies, including kidney diseases. Acute kidney injury (AKI) represents a syndrome seldom characterized by a single, distinct pathophysiological cause. Rhabdomyolysis-induced acute kidney injury (RIAKI) constitutes roughly 15% of AKI cases, yet its underlying pathophysiology remains poorly understood. Using a murine model of RIAKI induced by muscular glycerol injection, we observed elevated levels of AGEs and the AGE receptor galectin-3 (LGALS3) in the kidney. Immunofluorescence localized LGALS3 to distal nephron segments. According to transcriptomic profiling via next-generation sequencing, RIAKI led to profound changes in kidney metabolism, oxidative stress, and inflammation. Cellular stress was evident in both proximal and distal tubules, as shown by kidney injury markers KIM-1 and NGAL. However, only proximal tubules exhibited overt damage and apoptosis, as detected by routine morphology, active Caspase-3, and TUNEL assay, respectively. In vitro, distal convoluted tubule (DCT) cells challenged with AGEs underwent apoptosis, which was markedly enhanced by Lgals3 siRNA treatment. Thus, in RIAKI, the upregulation of LGALS3 may protect the distal nephron from AGE-mediated damage, while proximal tubules lacking LGALS3 stay at risk. Thus, stimulating LGALS3 in the proximal nephron, if achievable, may attenuate RIAKI.
Subject(s)
Acute Kidney Injury , Apoptosis , Galectin 3 , Kidney Tubules, Distal , Rhabdomyolysis , Animals , Male , Mice , Acute Kidney Injury/metabolism , Acute Kidney Injury/etiology , Acute Kidney Injury/pathology , Galectin 3/metabolism , Galectin 3/genetics , Glycation End Products, Advanced/metabolism , Kidney Tubules, Distal/metabolism , Mice, Inbred C57BL , Oxidative Stress , Rhabdomyolysis/metabolism , Rhabdomyolysis/complicationsABSTRACT
The purpose of this document is to provide guidance for establishing and maintaining growth and development of flow cytometry shared resource laboratories. While the best practices offered in this manuscript are not intended to be universal or exhaustive, they do outline key goals that should be prioritized to achieve operational excellence and meet the needs of the scientific community. Additionally, this document provides information on available technologies and software relevant to shared resource laboratories. This manuscript builds on the work of Barsky et al. 2016 published in Cytometry Part A and incorporates recent advancements in cytometric technology. A flow cytometer is a specialized piece of technology that require special care and consideration in its housing and operations. As with any scientific equipment, a thorough evaluation of the location, space requirements, auxiliary resources, and support is crucial for successful operation. This comprehensive resource has been written by past and present members of the International Society for Advancement of Cytometry (ISAC) Shared Resource Laboratory (SRL) Emerging Leaders Program https://isac-net.org/general/custom.asp?page=SRL-Emerging-Leaders with extensive expertise in managing flow cytometry SRLs from around the world in different settings including academia and industry. It is intended to assist in establishing a new flow cytometry SRL, re-purposing an existing space into such a facility, or adding a flow cytometer to an individual lab in academia or industry. This resource reviews the available cytometry technologies, the operational requirements, and best practices in SRL staffing and management.
Subject(s)
Laboratories , Software , Flow CytometryABSTRACT
Previous efforts to reconstruct evolutionary history of Palearctic ground squirrels within the genus Spermophilus have primarily relied on a single mitochondrial marker for phylogenetic data. In this study, we present the first phylogeny with comprehensive taxon sampling of Spermophilus via a conventional multilocus approach utilizing five mitochondrial and five nuclear markers. Through application of the multispecies coalescent model, we constructed a species tree revealing four distinct clades that diverged during the Late Miocene. These clades are 1) S. alaschanicus and S. dauricus from East Asia; 2) S. musicus and S. pygmaeus from East Europe and northwestern Central Asia; 3) the subgenus Colobotis found across Central Asia and its adjacent regions and encompassing S. brevicauda, S. erythrogenys, S. fulvus, S. major, S. pallidicauda, S. ralli, S. relictus, S. selevini, and S. vorontsovi sp. nov.; and 4) a Central/Eastern Europe and Asia Minor clade comprising S. citellus, S. taurensis, S. xanthoprymnus, S. suslicus, and S. odessanus. The latter clade lacked strong support owing to uncertainty of taxonomic placement of S. odessanus and S. suslicus. Resolving relationships within the subgenus Colobotis, which radiated rapidly, remains challenging likely because of incomplete lineage sorting and introgressive hybridization. Most of modern Spermophilus species diversified during the Early-Middle Pleistocene (2.2-1.0 million years ago). We propose a revised taxonomic classification for the genus Spermophilus by recognizing 18 species including a newly identified one (S. vorontsovi sp. nov.), which is found only in a limited area in the southeast of West Siberia. Employing genome-wide single-nucleotide polymorphism genotyping, we substantiated the role of the Ob River as a major barrier ensuring robust isolation of this taxon from S. erythrogenys. Despite its inherent limitations, the traditional multilocus approach remains a valuable tool for resolving relationships and can provide important insights into otherwise poorly understood groups. It is imperative to recognize that additional efforts are needed to definitively determine phylogenetic relationships between certain species of Palearctic ground squirrels.
Subject(s)
Genetic Introgression , Sciuridae , Animals , Siberia , Phylogeny , Sciuridae/genetics , AsiaABSTRACT
Autophagy is a conserved self-digestion process, which governs regulated degradation of cellular components. Autophagy is upregulated upon energy shortage sensed by AMP-dependent protein kinase (AMPK). Autophagy activators might be contemplated as therapies for metabolic neurodegenerative diseases and obesity, as well as cancer, considering tumor-suppressive functions of autophagy. Among them, 5-aminoimidazole-4-carboxamide ribonucleoside (AICAr), a nucleoside precursor of the active phosphorylated AMP analog, is the most commonly used pharmacological modulator of AMPK activity, despite its multiple reported "off-target" effects. Here, we assessed the autophagy/mitophagy activation ability of a small set of (2'-deoxy)adenosine derivatives and analogs using a fluorescent reporter assay and immunoblotting analysis. The first two leader compounds, 7,8-dihydro-8-oxo-2'-deoxyadenosine and -adenosine, are nucleoside forms of major oxidative DNA and RNA lesions. The third, a derivative of inactive N6-methyladenosine with a metabolizable phosphate-masking group, exhibited the highest activity in the series. These compounds primarily contributed to the activation of AMPK and outperformed AICAr; however, retaining the activity in knockout cell lines for AMPK (ΔAMPK) and its upstream regulator SIRT1 (ΔSIRT1) suggests that AMPK is not a main cellular target. Overall, we confirmed the prospects of searching for autophagy activators among (2'-deoxy)adenosine derivatives and demonstrated the applicability of the phosphate-masking strategy for increasing their efficacy.
Subject(s)
AMP-Activated Protein Kinases , Autophagy-Related Protein-1 Homolog , Autophagy , Humans , Adenosine/chemistry , Adenosine/metabolism , Aminoimidazole Carboxamide/analogs & derivatives , Aminoimidazole Carboxamide/pharmacology , Aminoimidazole Carboxamide/chemistry , AMP-Activated Protein Kinases/metabolism , Autophagy/drug effects , Autophagy-Related Protein-1 Homolog/metabolism , Deoxyadenosines/pharmacology , Deoxyadenosines/chemistry , Dose-Response Relationship, Drug , Intracellular Signaling Peptides and Proteins/metabolism , Molecular Structure , Structure-Activity RelationshipABSTRACT
We report the molecular mechanism of action of gausemycins and the isolation of new members of the family, gausemycins C (1c), D (1d), E (1e), and F (1f), the minor components of the mixture. To elucidate the mechanism of action of gausemycins, we investigated the antimicrobial activity of the most active compounds, gausemycins A and B, in the presence of Ca2+, other metal ions, and phosphate. Gausemycins require a significantly higher Ca2+ concentration for maximum activity than daptomycin but lower than that required for malacidine and cadasides. Species-specific antimicrobial activity was found upon testing against a wide panel of Gram-positive bacteria. Membranoactivity of gausemycins was demonstrated upon their interactions with model lipid bilayers and micelles. The pore-forming ability was found to be dramatically dependent on the Ca2+ concentration and the membrane lipid composition. An NMR study of gausemycin B in zwitterionic and anionic micelles suggested the putative structure of the gausemycin/membrane complex and revealed the binding of Ca2+ by the macrocyclic domain of the antibiotic.
Subject(s)
Anti-Bacterial Agents , Calcium , Gram-Positive Bacteria , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Calcium/metabolism , Molecular Structure , Gram-Positive Bacteria/drug effects , Cell Membrane/drug effects , Daptomycin/pharmacology , Daptomycin/chemistry , Lipid Bilayers/chemistry , MicellesABSTRACT
INTRODUCTION: Takotsubo cardiomyopathy (TTC), also known as stress-induced cardiomyopathy, resembles acute heart failure syndrome but lacks disease-specific diagnosis and treatment strategies. TTC accounts for approximately 5-6% of all suspected cases of acute coronary syndrome in women. At present, animal models of TTC are often created by large amounts of exogenous catecholamines such as isoproterenol. However, isoproterenol injection cannot fully simulate the onset of stress-induced cardiomyopathy in humans since stress is not an instantaneous event. METHODS: Rats were immobilized for 6 h per day for 1-14 days. To examine whether the TTC model was successful, echocardiography was employed; Elisa detected serum sympathetic activation markers; and the Open-Field test (OFT) was used to analyze behavioral changes in rats after stress. Western blot and histology were used to assess sympathetic remodeling, inflammation levels, and fibrosis; qRT-PCR was used to explore the levels of fibrosis and myocardial hypertrophy. The electrical stability of ventricular was determined by electrophysiological testing. RESULTS: The rats showed severe stress behavior and local sympathetic remodeling of the heart after only 1 day of stress. After 3 days of stress, the induction of ventricular tachyarrhythmia increased prominently. The highest incidence of TTC in rats was at 5 days of immobilization stress. The pathological left ventricular remodeling caused by immobilization (IMO) stress includes inflammatory infiltration, fibrosis, and myocardial hypertrophy. CONCLUSIONS: Our study confirms the hypothesis that IMO stress can mimic Takotsubo cardiomyopathy, and the various effects on the heart depending on the duration of IMO stress. We observed the highest incidence of TTC occurred after 5 days of stress. Furthermore, there is a gradual occurrence of electrical and structural remodeling as the stress duration prolongs.
Subject(s)
Takotsubo Cardiomyopathy , Humans , Female , Animals , Rats , Takotsubo Cardiomyopathy/diagnosis , Isoproterenol , Heart , Fibrosis , Hypertrophy/complicationsABSTRACT
In this review, we aim to summarize experimental data and approaches to identifying cellular targets or mechanisms of action of antibacterials based on imaging techniques. Imaging-based profiling methods, such as bacterial cytological profiling, dynamic bacterial morphology imaging, and others, have become a useful research tool for mechanistic studies of new antibiotics as well as combinations with conventional ones and other therapeutic options. The main methodological and experimental details and obtained results are summarized and discussed. The review covers the literature up to February 2024.
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Embryonic diapause in mammals leads to a reversible developmental arrest. While completely halted in many species, European roe deer (Capreolus capreolus) embryos display a continuous deceleration of proliferation. During a 4-mo period, the cell doubling time is 2 to 3 wk. During this period, the preimplantation blastocyst reaches a diameter of 4 mm, after which it resumes a fast developmental pace to subsequently implant. The mechanisms regulating this notable deceleration and reacceleration upon developmental resumption are unclear. We propose that amino acids of maternal origin drive the embryonic developmental pace. A pronounced change in the abundance of uterine fluid mTORC1-activating amino acids coincided with an increase in embryonic mTORC1 activity prior to the resumption of development. Concurrently, genes related to the glycolytic and phosphate pentose pathway, the TCA cycle, and one carbon metabolism were up-regulated. Furthermore, the uterine luminal epithelial transcriptome indicated increased estradiol-17ß signaling, which likely regulates the endometrial secretions adapting to the embryonic needs. While mTORC1 was predicted to be inactive during diapause, the residual embryonic mTORC2 activity may indicate its involvement in maintaining the low yet continuous proliferation rate during diapause. Collectively, we emphasize the role of nutrient signaling in preimplantation embryo development. We propose selective mTORC1 inhibition via uterine catecholestrogens and let-7 as a mechanism regulating slow stem cell cycle progression.
Subject(s)
Amino Acids/metabolism , Deer/embryology , Diapause , Embryo, Mammalian/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Animals , Blastocyst/cytology , Cell Proliferation , Cellular Microenvironment , Deer/physiology , Embryo, Mammalian/cytology , Embryonic Development , Female , Gene Expression Profiling , Pregnancy , Uterus/metabolismABSTRACT
AIMS: Long-term, placebo-controlled cholesterol-lowering trials have demonstrated legacy effects (clinical benefits that persist or emerge after trial end). It is unknown whether legacy effects follow a short period of very low low-density lipoprotein cholesterol (LDL-C) levels achieved with statin plus PCSK9 inhibitor. METHODS AND RESULTS: In 18,924 patients post-acute coronary syndrome, the ODYSSEY OUTCOMES trial compared the PCSK9 inhibitor alirocumab with placebo, each added to high-intensity or maximum-tolerated statin therapy. Patients with two consecutive LDL-C levels <0.39â mmol/L (15â mg/dL) on alirocumab had blinded placebo substitution for the remainder of the trial with continued statin treatment. In post hoc analyses, major adverse cardiovascular events (MACE) in these patients were compared to MACE in propensity score-matched patients from the placebo group with similar baseline characteristics and study medication adherence. In the alirocumab group, 730 patients had blinded placebo substitution at a median 8.3 months from randomization, after a median 6.0 months with LDL-C < 0.39â mmol/L. They were matched to 1460 placebo patients. Both groups had lower baseline LDL-C and lipoprotein(a) and better study medication adherence than the overall cohort. Over a median follow-up of 2.8 years, MACE occurred in 47 (6.4%) alirocumab patients with limited-duration, very low achieved LDL-C versus 122 (8.4%) matched placebo patients (treatment hazard ratio 0.72; 95% confidence interval 0.51, 0.997; P = 0.047). CONCLUSIONS: A short period of LDL-C levels <0.39â mmol/L achieved with statin and alirocumab, followed by statin monotherapy, was associated with lower risk of MACE than statin monotherapy throughout the observation period. Clinical benefit persisted for several years. TRIAL REGISTRATION: ClinicalTrials.gov NCT01663402.
ABSTRACT
An algorithm is developed for fully nonlinear three-dimensional (3D) simulation of a difference-frequency acoustic beam resulting from the interaction of two high-intensity pump waves. Simulations are performed in the frequency domain based on the Khokhlov-Zabolotskaya-Kuznetsov equation. A spectrum filtering method is used to enable accurate solutions for the difference-frequency fields in strongly nonlinear beams and with a high downshift frequency ratio using only dozens of spectral components retained in the algorithm. As an example, the dual-frequency operation of an underwater multi-element ellipsoidal array is considered, and numerical solutions describing parametric interactions in the array field are analyzed. It is shown that difference-frequency beams are more symmetric in transverse directions compared with the pump beams. The most efficient parametric generation of difference-frequency beams corresponded to close and beyond shock-forming conditions. Axial pressure amplitude of the difference frequency was shown to grow first quadratically with the source pressure following the quasi-linear solution and then linearly once shocks start to develop. The percentage of the total power converted to the difference frequency from pump waves increased at high power outputs without saturation. Up to twofold increase in directivity angles of difference-frequency beams under shock-forming conditions was observed compared with quasi-linear conditions.
ABSTRACT
The analysis of small particles, including extracellular vesicles and viruses, is contingent on their ability to scatter sufficient light to be detected. These detection methods include flow cytometry, nanoparticle tracking analysis, and single particle reflective image sensing. To standardize measurements and enable orthogonal comparisons between platforms, a quantifiable limit of detection is required. The main parameters that dictate the amount of light scattered by particles include size, morphology, and refractive index. To date, there has been a lack of accessible techniques for measuring the refractive index of nanoparticles at a single-particle level. Here, we demonstrate two methods of deriving a small particle refractive index using orthogonal measurements with commercially available platforms. These methods can be applied at either a single-particle or population level, enabling the integration of diameter and scattering cross section values to derive the refractive index using Mie theory.
Subject(s)
Extracellular Vesicles , Nanoparticles , Humans , Refractometry , Flow Cytometry/methodsABSTRACT
Anemonopsis Siebold et Zucc. is an unstudied single-species genus belonging to the tribe Cimicifugeae (Ranunculaceae). The only species of this genus-Anemonopsis macrophylla Siebold and Zucc.-is endemic to Japan. There are no data on its chemical composition. This work is the first to determine (with liquid chromatography-high-resolution mass spectrometry, LC-HRMS) the chemical composition of methanol extracts of leaves and flowers of A. macrophylla. More than 100 compounds were identified. In this plant, the classes of substances are coumarins (13 compounds), furocoumarins (3), furochromones (2), phenolic acids (21), flavonoids (27), and fatty acids and their derivatives (15 compounds). Isoferulic acid (detected in extracts from this plant) brings this species closer to plants of the genus Cimicifuga, one of the few genera containing this acid and ferulic acid at the same time. Isoferulic acid is regarded as a reference component of a quality indicator of Cimicifuga raw materials. The determined profiles of substances are identical between the leaf and flower methanol extracts. Differences in levels of some identified substances were revealed between the leaf and flower extracts of A. macrophylla; these differences may have a substantial impact on the manifestation of the biological and pharmacological effects of the extracts in question.
Subject(s)
Cinnamates , Ranunculaceae , Methanol , Plant Leaves , FlowersABSTRACT
Metaparasitylenchus hypothenemi is a nematode that naturally parasitizes Hypothenemus hampei in a coffee-producing region in Chiapas, Mexico. This study investigated changes in the attraction of parasitized borers to light. We compared the attraction of adult H. hampei females (parasitized and uninfected) to 14 different light wavelengths (350-670 nm) with a control (570 nm, yellow) under laboratory conditions. The response ranges of non-parasitized and parasitized borers were 370-650 nm and 340-650 nm, respectively. The attraction curve showed a similar shape in both borer groups (parasitized and non-parasitized), but a wide wavelength range (380-590 nm) attracted more parasitized than non-parasitized borers. The maximum response of the uninfected borers occurred at 520 nm (green), while parasitized borers exhibited three response peaks (380 nm, violet; 460 nm, blue; 520 nm, green). Parasitized borers were significantly more attracted to green light (520 nm) than to the control. The altered attraction to light in borers parasitized by M. hypothenemi is discussed from the perspective of possible host manipulation and the natural prevalence of this parasite.
ABSTRACT
BACKGROUND: Apolipoprotein B (apoB) provides an integrated measure of atherogenic risk. Whether apoB levels and apoB lowering hold incremental predictive information on residual risk after acute coronary syndrome beyond that provided by low-density lipoprotein cholesterol is uncertain. METHODS: The ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) compared the proprotein convertase subtilisin/kexin type 9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome and elevated atherogenic lipoproteins despite optimized statin therapy. Primary outcome was major adverse cardiovascular events (MACE; coronary heart disease death, nonfatal myocardial infarction, fatal/nonfatal ischemic stroke, hospitalization for unstable angina). Associations between baseline apoB or apoB at 4 months and MACE were assessed in adjusted Cox proportional hazards and propensity score-matched models. RESULTS: Median follow-up was 2.8 years. In proportional hazards analysis in the placebo group, MACE incidence increased across increasing baseline apoB strata (3.2 [95% CI, 2.9-3.6], 4.0 [95% CI, 3.6-4.5], and 5.5 [95% CI, 5.0-6.1] events per 100 patient-years in strata <75, 75-<90, ≥90 mg/dL, respectively; Ptrend<0.0001) and after adjustment for low-density lipoprotein cholesterol (Ptrend=0.035). Higher baseline apoB stratum was associated with greater relative (Ptrend<0.0001) and absolute reduction in MACE with alirocumab versus placebo. In the alirocumab group, the incidence of MACE after month 4 decreased monotonically across decreasing achieved apoB strata (4.26 [95% CI, 3.78-4.79], 3.09 [95% CI, 2.69-3.54], and 2.41 [95% CI, 2.11-2.76] events per 100 patient-years in strata ≥50, >35-<50, and ≤35 mg/dL, respectively). Compared with propensity score-matched patients from the placebo group, treatment hazard ratios for alirocumab also decreased monotonically across achieved apoB strata. Achieved apoB was predictive of MACE after adjustment for achieved low-density lipoprotein cholesterol or non-high-density lipoprotein cholesterol but not vice versa. CONCLUSIONS: In patients with recent acute coronary syndrome and elevated atherogenic lipoproteins, MACE increased across baseline apoB strata. Alirocumab reduced MACE across all strata of baseline apoB, with larger absolute reductions in patients with higher baseline levels. Lower achieved apoB was associated with lower risk of MACE, even after accounting for achieved low-density lipoprotein cholesterol or non-high-density lipoprotein cholesterol, indicating that apoB provides incremental information. Achievement of apoB levels as low as ≤35 mg/dL may reduce lipoprotein-attributable residual risk after acute coronary syndrome. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01663402.
Subject(s)
Acute Coronary Syndrome , Anticholesteremic Agents , Atherosclerosis , Cardiovascular Diseases , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/drug therapy , Acute Coronary Syndrome/epidemiology , Antibodies, Monoclonal, Humanized , Anticholesteremic Agents/adverse effects , Apolipoproteins B , Atherosclerosis/drug therapy , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Cholesterol , Cholesterol, LDL , Heart Disease Risk Factors , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Risk Factors , Treatment OutcomeABSTRACT
The search for new drugs has been greatly accelerated by the emergence of new viruses and drug-resistant strains of known pathogens. Nucleoside analogues (NAs) are a prospective class of antivirals due to known safety profiles, which are important for rapid repurposing in the fight against emerging pathogens. Recent improvements in research methods have revealed new unexpected details in the mechanisms of action of NAs that can pave the way for new approaches for the further development of effective drugs. This review accounts advanced techniques in viral polymerase targeting, new viral and host enzyme targeting approaches, and prodrug-based strategies for the development of antiviral NAs.