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1.
Cell ; 167(6): 1571-1585.e18, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27839864

RESUMO

Cell migration in confined 3D tissue microenvironments is critical for both normal physiological functions and dissemination of tumor cells. We discovered a cytoskeletal structure that prevents damage to the nucleus during migration in confined microenvironments. The formin-family actin filament nucleator FMN2 associates with and generates a perinuclear actin/focal adhesion (FA) system that is distinct from previously characterized actin/FA structures. This system controls nuclear shape and positioning in cells migrating on 2D surfaces. In confined 3D microenvironments, FMN2 promotes cell survival by limiting nuclear envelope damage and DNA double-strand breaks. We found that FMN2 is upregulated in human melanomas and showed that disruption of FMN2 in mouse melanoma cells inhibits their extravasation and metastasis to the lung. Our results indicate a critical role for FMN2 in generating a perinuclear actin/FA system that protects the nucleus and DNA from damage to promote cell survival during confined migration and thus promote cancer metastasis.


Assuntos
Núcleo Celular/metabolismo , Adesões Focais , Neoplasias Pulmonares/secundário , Melanoma/patologia , Proteínas dos Microfilamentos/metabolismo , Metástase Neoplásica , Proteínas Nucleares/metabolismo , Actinas/metabolismo , Animais , Quebras de DNA de Cadeia Dupla , Embrião de Mamíferos/citologia , Matriz Extracelular/metabolismo , Feminino , Forminas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso
3.
Nature ; 612(7938): 83-87, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36289345

RESUMO

Achieving carbon neutrality requires deploying renewable energy at unprecedented speed and scale1,2, yet countries sometimes implement policies that increase costs by restricting the free flow of capital, talent and innovation in favour of localizing benefits such as economic growth, employment and trade surpluses3,4. Here we assess the cost savings from a globalized solar photovoltaic (PV) module supply chain. We develop a two-factor learning model using historical capacity, component and input material price data of solar PV deployment in the United States, Germany and China. We estimate that the globalized PV module market has saved PV installers US$24 (19-31) billion in the United States, US$7 (5-9) billion in Germany and US$36 (26-45) billion in China from 2008 to 2020 compared with a counterfactual scenario in which domestic manufacturers supply an increasing proportion of installed capacities over a ten-year period. Projecting the same scenario forwards from 2020 results in estimated solar module prices that are approximately 20-25 per cent higher in 2030 compared with a future with globalized supply chains. International climate policy benefits from a globalized low-carbon value chain4, and these results point to the need for complementary policies to mitigate welfare distribution effects and potential impacts on technological crowding out.

4.
Cell ; 151(6): 1370-85, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23217717

RESUMO

Optical imaging of the dynamics of living specimens involves tradeoffs between spatial resolution, temporal resolution, and phototoxicity, made more difficult in three dimensions. Here, however, we report that rapid three-dimensional (3D) dynamics can be studied beyond the diffraction limit in thick or densely fluorescent living specimens over many time points by combining ultrathin planar illumination produced by scanned Bessel beams with super-resolution structured illumination microscopy. We demonstrate in vivo karyotyping of chromosomes during mitosis and identify different dynamics for the actin cytoskeleton at the dorsal and ventral surfaces of fibroblasts. Compared to spinning disk confocal microscopy, we demonstrate substantially reduced photodamage when imaging rapid morphological changes in D. discoideum cells, as well as improved contrast and resolution at depth within developing C. elegans embryos. Bessel beam structured plane illumination thus promises new insights into complex biological phenomena that require 4D subcellular spatiotemporal detail in either a single or multicellular context.


Assuntos
Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Animais , Encéfalo/citologia , Encéfalo/ultraestrutura , Caenorhabditis elegans/citologia , Caenorhabditis elegans/crescimento & desenvolvimento , Linhagem Celular , Linhagem Celular Tumoral , Dermatite Fototóxica , Dictyostelium/ultraestrutura , Drosophila melanogaster/citologia , Fibroblastos/ultraestrutura , Humanos , Cariotipagem/métodos , Larva/citologia , Larva/ultraestrutura , Mitose
5.
Proc Natl Acad Sci U S A ; 121(8): e2215674121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38359297

RESUMO

Sustainability outcomes are influenced by the laws and configurations of natural and engineered systems as well as activities in socio-economic systems. An important subset of human activity is the creation and implementation of institutions, formal and informal rules shaping a wide range of human behavior. Understanding these rules and codifying them in computational models can provide important missing insights into why systems function the way they do (static) as well as the pace and structure of transitions required to improve sustainability (dynamic). Here, we conduct a comparative synthesis of three modeling approaches- integrated assessment modeling, engineering-economic optimization, and agent-based modeling-with underexplored potential to represent institutions. We first perform modeling experiments on climate mitigation systems that represent specific aspects of heterogeneous institutions, including formal policies and institutional coordination, and informal attitudes and norms. We find measurable but uneven aggregate impacts, while more politically meaningful distributional impacts are large across various actors. Our results show that omitting institutions can influence the costs of climate mitigation and miss opportunities to leverage institutional forces to speed up emissions reduction. These experiments allow us to explore the capacity of each modeling approach to represent insitutions and to lay out a vision for the next frontier of endogenizing institutional change in sustainability science models. To bridge the gap between modeling, theories, and empirical evidence on social institutions, this research agenda calls for joint efforts between sustainability modelers who wish to explore and incorporate institutional detail, and social scientists studying the socio-political and economic foundations for sustainability transitions.


Assuntos
Modelos Teóricos , Análise de Sistemas , Humanos
6.
Proc Natl Acad Sci U S A ; 121(10): e2306517121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38408236

RESUMO

China has committed to achieve net carbon neutrality by 2060 to combat global climate change, which will require unprecedented deployment of negative emissions technologies, renewable energies (RE), and complementary infrastructure. At terawatt-scale deployment, land use limitations interact with operational and economic features of power systems. To address this, we developed a spatially resolved resource assessment and power systems planning optimization that models a full year of power system operations, sub-provincial RE siting criteria, and transmission connections. Our modeling results show that wind and solar must be expanded to 2,000 to 3,900 GW each, with one plausible pathway leading to 300 GW/yr combined annual additions in 2046 to 2060, a three-fold increase from today. Over 80% of solar and 55% of wind is constructed within 100 km of major load centers when accounting for current policies regarding land use. Large-scale low-carbon systems must balance key trade-offs in land use, RE resource quality, grid integration, and costs. Under more restrictive RE siting policies, at least 740 GW of distributed solar would become economically feasible in regions with high demand, where utility-scale deployment is limited by competition with agricultural land. Effective planning and policy formulation are necessary to achieve China's climate goals.

7.
J Am Soc Nephrol ; 35(1): 74-84, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38088558

RESUMO

SIGNIFICANCE STATEMENT: Systemic inflammation in CKD can lead to anemia. Ziltivekimab, a fully human monoclonal antibody targeting the IL-6 ligand, has been shown to reduce systemic inflammation in patients with CKD. It has also been shown to increase serum albumin in patients on hemodialysis with inflammation and hyporesponsiveness to treatment with erythropoiesis-stimulating agents. This exploratory analysis of the RESCUE clinical trial found that among patients with CKD stage 3-5 and systemic inflammation, ziltivekimab treatment significantly increased hemoglobin (Hb) levels after 12 weeks compared with placebo. Ziltivekimab was also associated with significant increases in serum iron levels, total iron-binding capacity, and transferrin saturation. No major safety concerns were reported. Further clinical trials are warranted to study ziltivekimab's potential for anemia management in patients with CKD. BACKGROUND: In the phase 2 RESCUE clinical trial, ziltivekimab, a fully human monoclonal antibody against the IL-6 ligand, significantly reduced the biomarkers of inflammation compared with placebo, in patients with CKD and systemic inflammation (high-sensitivity C-reactive protein ≥2 mg/L). The aim of this subanalysis of RESCUE trial data was to assess the effect of ziltivekimab on Hb and iron homeostasis in this patient population. METHODS: This was an analysis of exploratory end points from the RESCUE trial ( NCT03926117 ), which included 264 adults with CKD stage 3-5 and high-sensitivity C-reactive protein ≥2 mg/L. Participants received placebo or subcutaneous ziltivekimab (7.5, 15, or 30 mg) (1:1:1:1) once every 4 weeks, up to 24 weeks. End points for this analysis were changes in Hb and biomarkers of iron homeostasis from baseline to week 12. RESULTS: The trial was terminated early due to the coronavirus disease 2019 pandemic, and thus, data up to week 12 are presented. Hb levels significantly increased from baseline to week 12 with ziltivekimab 7.5, 15, and 30 mg (treatment differences versus placebo: +0.57 g/dl [95% confidence interval, 0.27 to 0.86], +1.05 g/dl [0.76 to 1.33], and +0.99 g/dl [0.70 to 1.28], respectively, all P < 0.001). Ziltivekimab was associated with significant increases in serum iron levels, total iron-binding capacity, and transferrin saturation from baseline to week 12 ( P < 0.05 versus placebo for all doses and comparisons). Cases of sustained thrombocytopenia, sustained neutropenia, anemia, and iron deficiency anemia were infrequent and similar across all groups. CONCLUSIONS: Anti-inflammatory therapy with ziltivekimab improved the markers of anemia and iron homeostasis in people with stage 3-5 CKD and systemic inflammation, suggesting a possible role in anemia management.


Assuntos
Anemia , Falência Renal Crônica , Insuficiência Renal Crônica , Adulto , Humanos , Compostos Férricos/uso terapêutico , Proteína C-Reativa/metabolismo , Proteína C-Reativa/uso terapêutico , Interleucina-6/metabolismo , Ligantes , Falência Renal Crônica/complicações , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anemia/tratamento farmacológico , Anemia/etiologia , Hemoglobinas/metabolismo , Ferro/metabolismo , Inflamação/complicações , Biomarcadores , Transferrinas
8.
Am Heart J ; 274: 32-45, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38705341

RESUMO

BACKGROUND: Obicetrapib, a novel, selective cholesteryl ester transfer protein (CETP) inhibitor, reduces low-density lipoprotein cholesterol (LDL-C), LDL particles, apolipoprotein (Apo) B, and lipoprotein(a) [Lp(a)] and increases high-density lipoprotein cholesterol (HDL-C) when added to statins with or without ezetimibe. By substantially reducing LDL-C, obicetrapib has the potential to lower atherogenic lipoproteins in patients with atherosclerotic cardiovascular disease (ASCVD) or heterozygous familial hypercholesterolemia (HeFH) whose LDL-C levels remain high despite treatment with available maximally tolerated lipid-modifying therapies, addressing an unmet medical need in a patient population at high risk for cardiovascular events. METHODS AND RESULTS: BROADWAY (NCT05142722) and BROOKLYN (NCT05425745) are ongoing placebo-controlled, double-blind, randomized Phase III trials designed to examine the efficacy, safety, and tolerability of obicetrapib as an adjunct to dietary intervention and maximally tolerated lipid-modifying therapies in participants with a history of ASCVD and/or underlying HeFH whose LDL-C is not adequately controlled. The primary efficacy endpoint was the percent change in LDL-C from baseline to day 84. Other endpoints included changes in Apo B, non-HDL-C, HDL-C, Apo A1, Lp(a), and triglycerides in addition to parameters evaluating safety, tolerability, and pharmacokinetics. BROADWAY also included an adjudicated assessment of major adverse cardiovascular events, measurements of glucose homeostasis, and an ambulatory blood pressure monitoring substudy. A total of 2,532 participants were randomized in BROADWAY and 354 in BROOKLYN to receive obicetrapib 10 mg or placebo (2:1) for 365 days with follow-up through 35 days after the last dose. Results from both trials are anticipated in 2024. CONCLUSION: These trials will provide safety and efficacy data to support the potential use of obicetrapib among patients with ASCVD or HeFH with elevated LDL-C for whom existing therapies are not sufficiently effective or well-tolerated.


Assuntos
Anticolesterolemiantes , Aterosclerose , LDL-Colesterol , Humanos , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Anticolesterolemiantes/uso terapêutico , Anticolesterolemiantes/administração & dosagem , Método Duplo-Cego , LDL-Colesterol/sangue , Masculino , Feminino , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , HDL-Colesterol/sangue , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/complicações , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipoproteína(a)/sangue , Pessoa de Meia-Idade
9.
Curr Atheroscler Rep ; 26(2): 35-44, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38133847

RESUMO

PURPOSE OF REVIEW: To discuss the history of cardiovascular outcomes trials of cholesteryl ester transfer protein (CETP) inhibitors and to describe obicetrapib, a next-generation, oral, once-daily, low-dose CETP inhibitor in late-stage development for dyslipidemia and atherosclerotic cardiovascular disease (ASCVD). RECENT FINDINGS: Phase 1 and 2 trials have evaluated the safety and lipid/lipoprotein effects of obicetrapib as monotherapy, in conjunction with statins, on top of high-intensity statins (HIS), and with ezetimibe on top of HIS. In ROSE2, 10 mg obicetrapib monotherapy and combined with 10 mg ezetimibe, each on top of HIS, significantly reduced low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), apolipoprotein B, total LDL particles, small LDL particles, small, dense LDL-C, and lipoprotein (a), and increased HDL-C. Phase 3 pivotal registration trials including a cardiovascular outcomes trial are underway. Obicetrapib has an excellent safety and tolerability profile and robustly lowers atherogenic lipoproteins and raises HDL-C. As such, obicetrapib may be a promising agent for the treatment of ASCVD.


Assuntos
Aterosclerose , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Proteínas de Transferência de Ésteres de Colesterol , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , LDL-Colesterol , HDL-Colesterol , Aterosclerose/tratamento farmacológico , Lipoproteínas , Ezetimiba
10.
Immunity ; 42(5): 864-76, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25992860

RESUMO

Cytotoxic T lymphocytes (CTLs) use polarized secretion to rapidly destroy virally infected and tumor cells. To understand the temporal relationships between key events leading to secretion, we used high-resolution 4D imaging. CTLs approached targets with actin-rich projections at the leading edge, creating an initially actin-enriched contact with rearward-flowing actin. Within 1 min, cortical actin reduced across the synapse, T cell receptors (TCRs) clustered centrally to form the central supramolecular activation cluster (cSMAC), and centrosome polarization began. Granules clustered around the moving centrosome within 2.5 min and reached the synapse after 6 min. TCR-bearing intracellular vesicles were delivered to the cSMAC as the centrosome docked. We found that the centrosome and granules were delivered to an area of membrane with reduced cortical actin density and phospholipid PIP2. These data resolve the temporal order of events during synapse maturation in 4D and reveal a critical role for actin depletion in regulating secretion.


Assuntos
Actinas/metabolismo , Grânulos Citoplasmáticos/metabolismo , Sinapses Imunológicas/metabolismo , Linfócitos T Citotóxicos/citologia , Membrana Celular/química , Células Cultivadas , Grânulos Citoplasmáticos/química , Imunofluorescência , Humanos , Modelos Imunológicos , Fosfolipídeos/metabolismo , Linfócitos T Citotóxicos/metabolismo
11.
Langmuir ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994807

RESUMO

We use sequence-specific polypeptoids to characterize the impact of the monomer sequence on the adsorption of surface-active polymers at fluid/fluid interfaces. Sets of 36 repeat unit polypeptoids with identical chemical composition, but different sequences of hydrophobic moieties along the oligomer chain (taper, inverse taper, blocky, and evenly distributed), are designed and characterized at air/water interfaces. Polypeptoids are driven to the interfaces by decreasing the solvent quality of the aqueous solution. In situ processing of the adsorbed layers causes a collapse of polypeptoids and the formation of irreversibly adsorbed, solvent-avoiding layers at interfaces. Differences in thermodynamic properties, driven by solubility, between the collapsed structures at interfaces are studied with measurements of interfacial tension. The dilatational modulus of polypeptoid-coated interfaces is used as a proxy to probe the extent of the coil-globule collapse at the interface. The role of hydrophobicity is investigated by comparing four sequences of polypeptoids with an increased size of the hydrophilic side chains. In each set of polypeptoids, the composition of molecules, not the sequence, controls the surface concentration. The molecules are described in terms of the distribution of the hydrophobic monomers on the backbone of the polymer. Inverse taper (IT) and blocky (B) sequences of hydrophobic moieties favor the formation of highly elastic interfaces after processing, while taper (T) and distributed (D) showed lower elasticity after processing, which is achieved by replacing good solvent with poor solvent and then nonsolvent. These structures allow for the study of the impact of the chemical composition and sequence of monomers on the properties of polymer-coated interfaces.

13.
Psychol Med ; 53(7): 2878-2884, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34911593

RESUMO

BACKGROUND: Although the ICD and DSM differentiate between different psychiatric disorders, these often share symptoms, risk factors, and treatments. This was a population-based, case-control, sibling study examining familial clustering of all psychiatric disorders and low IQ, using data from the Israel Draft-Board Registry on all Jewish adolescents assessed between 1998 and 2014. METHODS: We identified all cases with autism spectrum disorder (ASD, N = 2128), severe intellectual disability (ID, N = 9572), attention-deficit hyperactive disorder (ADHD) (N = 3272), psychotic (N = 7902), mood (N = 9704), anxiety (N = 10 606), personality (N = 24 816), or substance/alcohol abuse (N = 791) disorders, and low IQ (⩾2 SDs below the population mean, N = 31 186). Non-CNS control disorders were adolescents with Type-1 diabetes (N = 2427), hernia (N = 29 558) or hematological malignancies (N = 931). Each case was matched with 10 age-matched controls selected at random from the Draft-Board Registry, with replacement, and for each case and matched controls, we ascertained all full siblings. The main outcome measure was the relative recurrence risk (RRR) of the sibling of a case having the same (within-disorder RRR) or a different (across-disorder RRR) disorder. RESULTS: Within-disorder RRRs were increased for all diagnostic categories, ranging from 11.53 [95% confidence interval (CI): 9.23-14.40] for ASD to 2.93 (95% CI: 2.80-3.07) for personality disorders. The median across-disorder RRR between any pair of psychiatric disorders was 2.16 (95% CI: 1.45-2.43); the median RRR between low IQ and any psychiatric disorder was 1.37 (95% CI: 0.93-1.98). There was no consistent increase in across-disorder RRRs between the non-CNS disorders and psychiatric disorders and/or low IQ. CONCLUSION: These large population-based study findings suggest shared etiologies among most psychiatric disorders, and low IQ.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Deficiência Intelectual , Adolescente , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/genética , Recidiva Local de Neoplasia , Fatores de Risco , Estudos de Casos e Controles
14.
Mol Psychiatry ; 27(7): 3107-3114, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35459901

RESUMO

Previous studies on psychiatric patients infected with COVID-19 have reported a more severe course of disease and higher rates of mortality compared with the general population. This cohort study linked Israeli national databases including all individuals ever hospitalized for a psychiatric disorder (cases), and COVID-19 testing, infection, hospitalization, mortality, and vaccinations, between March 1st 2020 and March 31st 2021. Cases were 125,273 individuals aged 18 and above ever hospitalized in a psychiatric facility (ICD-10 F10-F69 or F90-F99), compared to the total population, n = 6,143,802. Compared with the total population, cases were less likely to be tested for COVID-19, 51.2% (95% CI: 50.8-51.7) vs 62.3% (95% CI 62.2-62.4) and had lower rates of confirmed COVID infection, 5.9% (95% CI: 5.8-6.1) vs 8.9% (95% CI: 8.9-8.9). Among those infected, risks for COVID-19 hospitalization, COVID-19 attributed mortality and all-cause mortality were higher for cases than the total population, adjusted odds ratios were 2.10; (95% CI: 1.96-2.25), 1.76; (95% CI: 1.54-2.01) and 2.02; (95% CI: 1.80-2.28), respectively. These risks were even higher for cases with non-affective psychotic disorders and bipolar disorder. Age adjusted rates of vaccination were lower in cases, 60.4% (95% CI: 59.9-60.8) vs 74.9% (95% CI: 74.8-75.0) in the total population, and particularly low for cases with non-affective psychotic disorders, 56.9% (95% CI: 56.3-57.6). This study highlights the need to increase testing for COVID-19 in individuals ever hospitalized for a psychiatric disorder, closely monitor those found positive, and to reach out to encourage vaccination.


Assuntos
COVID-19 , Transtornos Mentais , Teste para COVID-19 , Estudos de Coortes , Hospitalização , Humanos , Israel/epidemiologia , Transtornos Mentais/epidemiologia , Vacinação
15.
Arterioscler Thromb Vasc Biol ; 42(12): 1461-1467, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36325899

RESUMO

BACKGROUND: Severe hypertriglyceridemia is often caused by variants in genes of triglyceride metabolism. These variants include rare, heterozygous pathogenic variants (PVs), or multiple common, small-effect single nucleotide polymorphisms that can be quantified using a polygenic risk score (PRS). The role of genetic testing to examine PVs and PRS in predicting risk for pancreatitis and severity of hypertriglyceridemia is unknown. METHODS: We examined the relationship of PVs and PRSs associated with hypertriglyceridemia with the highest recorded plasma triglyceride level and risk for acute pancreatitis in 363 patients from 3 academic lipid clinics who underwent genetic testing (GBinsight's Dyslipidemia Comprehensive Panel). Categories of hypertriglyceridemia included: normal triglyceride (<200 mg/dL), moderate (200-499 mg/dL), severe (500-999 mg/dL), or very severe (≥1000 mg/dL). RESULTS: PVs and high PRSs were identified in 37 (10%) and 59 (16%) individuals, respectively. Patients with both had increased risk for very severe hypertriglyceridemia compared with those with neither genetic risk factor. Risk for acute pancreatitis was also increased in individuals with both genetic risk factors (odds ratio, 5.1 [P=0.02] after controlling for age, race, sex, body mass index, and highest triglyceride level), but not in individuals with PV or high PRS alone. CONCLUSIONS: The presence of both PV and high PRS significantly increased risk for very severe hypertriglyceridemia and acute pancreatitis, whereas PV or PRS alone only modestly increased risk. Genetic testing may help identify patients with hypertriglyceridemia who have the greatest risk for developing pancreatitis and may derive the greatest benefit from novel triglyceride-lowering therapies.


Assuntos
Hipertrigliceridemia , Pancreatite , Humanos , Pancreatite/diagnóstico , Pancreatite/genética , Doença Aguda , Medicina de Precisão , Hipertrigliceridemia/diagnóstico , Hipertrigliceridemia/genética , Triglicerídeos , Testes Genéticos
16.
Nature ; 546(7656): 162-167, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28538724

RESUMO

The organization of the eukaryotic cell into discrete membrane-bound organelles allows for the separation of incompatible biochemical processes, but the activities of these organelles must be coordinated. For example, lipid metabolism is distributed between the endoplasmic reticulum for lipid synthesis, lipid droplets for storage and transport, mitochondria and peroxisomes for ß-oxidation, and lysosomes for lipid hydrolysis and recycling. It is increasingly recognized that organelle contacts have a vital role in diverse cellular functions. However, the spatial and temporal organization of organelles within the cell remains poorly characterized, as fluorescence imaging approaches are limited in the number of different labels that can be distinguished in a single image. Here we present a systems-level analysis of the organelle interactome using a multispectral image acquisition method that overcomes the challenge of spectral overlap in the fluorescent protein palette. We used confocal and lattice light sheet instrumentation and an imaging informatics pipeline of five steps to achieve mapping of organelle numbers, volumes, speeds, positions and dynamic inter-organelle contacts in live cells from a monkey fibroblast cell line. We describe the frequency and locality of two-, three-, four- and five-way interactions among six different membrane-bound organelles (endoplasmic reticulum, Golgi, lysosome, peroxisome, mitochondria and lipid droplet) and show how these relationships change over time. We demonstrate that each organelle has a characteristic distribution and dispersion pattern in three-dimensional space and that there is a reproducible pattern of contacts among the six organelles, that is affected by microtubule and cell nutrient status. These live-cell confocal and lattice light sheet spectral imaging approaches are applicable to any cell system expressing multiple fluorescent probes, whether in normal conditions or when cells are exposed to disturbances such as drugs, pathogens or stress. This methodology thus offers a powerful descriptive tool and can be used to develop hypotheses about cellular organization and dynamics.


Assuntos
Microscopia Confocal , Imagem Molecular/métodos , Organelas/metabolismo , Biologia de Sistemas , Animais , Células COS , Sobrevivência Celular , Chlorocebus aethiops , Cor , Citoesqueleto , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Metabolismo dos Lipídeos , Lisossomos/metabolismo , Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Organelas/química , Peroxissomos/metabolismo , Análise Espaço-Temporal
17.
J Oncol Pharm Pract ; : 10781552231164301, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36942434

RESUMO

INTRODUCTION: The tyrosine-kinase inhibitor osimertinib is an oral anti-cancer agent that is used for the treatment of patients with metastatic non-small cell lung cancer harbouring sensitising EGFR mutations. Patients receiving osimertinib are at higher risk of developing cardiac toxicity, and here we present the case of a 72-year-old male who developed multiple cardiotoxicities during therapy (i.e. QTc prolongation, atrial fibrillation, heart failure). CASE REPORT: A 72-year-old white British, ex-smoker male patient was admitted to our cancer centre with adenocarcinoma of the lung. Afatinib, gefitinib, osimertinib, and carboplatin plus pemetrexed chemotherapy were the treatments he received. At the 15th month of osimertinib therapy, the patient developed QTc prolongation. Two weeks after the first incidence of QTc prolongation, electrocardiography showed rate-controlled atrial fibrillation. In addition to his atrial fibrillation, echocardiography revealed severely impaired left ventricular systolic function (left ventricular ejection fraction: 30%). MANAGEMENT AND OUTCOMES: Baseline to osimertinib, an electrocardiography investigation was carried out as per the protocol. Baseline drug history was reviewed and rosuvastatin was discontinued before initiating osimertinib as both drugs contribute to QTc prolongation. Dabigatran, bisoprolol, and digoxin were started for the treatment of atrial fibrillation. Ramipril and spironolactone were prescribed for the treatment of heart failure but osimertinib continued uneventfully. The patient died of non-small cell lung cancer. DISCUSSION: Recommendations for practical and clinically relevant baseline and on-treatment assessments are considered which may reduce the risk of cardiac toxicity during osimertinib therapy. These include baseline cardiac risk stratification, consideration of concomitant medications that may result in additive cardiac risk, and use of electrocardiography and echocardiography surveillance.

18.
Vet Ophthalmol ; 26(4): 297-305, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36692054

RESUMO

PURPOSE: To evaluate the normal refractive state in horses in NCSU and ECMR and determine the prevalence of naturally occurring refractive errors and their association with breed, age, coat color, iris color, sex, and geographic location. METHODS: Horses from NCSU (January 2009-November 2012) and ECMR (January 2013-September 2016) underwent ophthalmic examination and streak retinoscopy. Location, color, breed, sex, and iris color were recorded. Gross and net refractive values for each meridian (horizontal and vertical), spherical refraction, astigmatism for both eyes, and anisometry were recorded, and statistical analyses were performed. RESULTS: There is excellent agreement in refraction between the eyes of the same horse (ICC = 0.89). The median net horizontal (H), vertical (V), and spherical refraction for the total population (n = 690) were H: +0.25 D (min. -6.50 D, max. +2.34 D), V: +0.25 D (min. -7.13 D, max. +2.75D), and spherical: +0.25 D (min. -6.82 D, max. +2.17 D), all with interquartile ranges of -0.25 to 0.25 D. Emmetropia (>-0.50 D and <+0.50 D; >-0.75 D and <+0.75 D) was present in 769/1380 eyes (55.7%) and 926/1380 eyes (67.1%), respectively. Anisometropia was present in 86/690 horses (12.5%). Sex, iris color, and location were significantly associated with refraction values, whereas age, breed, and coat color were not. CONCLUSIONS: Most eyes evaluated are emmetropic, or shifted myopically, with excellent agreement between eyes of the same horse. Sex, iris color, and geographic location appear to impact refraction in horses. SUPPORT: None.


Assuntos
Doenças dos Cavalos , Erros de Refração , Cavalos , Animais , Prevalência , North Carolina , Erros de Refração/epidemiologia , Erros de Refração/veterinária , Refração Ocular , Alemanha/epidemiologia , Iris
19.
Lancet ; 397(10289): 2060-2069, 2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-34015342

RESUMO

BACKGROUND: IL-6 has emerged as a pivotal factor in atherothrombosis. Yet, the safety and efficacy of IL-6 inhibition among individuals at high atherosclerotic risk but without a systemic inflammatory disorder is unknown. We therefore addressed whether ziltivekimab, a fully human monoclonal antibody directed against the IL-6 ligand, safely and effectively reduces biomarkers of inflammation and thrombosis among patients with high cardiovascular risk. We focused on individuals with elevated high-sensitivity CRP and chronic kidney disease, a group with substantial unmet clinical need in whom previous studies in inflammation inhibition have shown efficacy for cardiovascular event reduction. METHODS: RESCUE is a randomised, double-blind, phase 2 trial done at 40 clinical sites in the USA. Inclusion criteria were age 18 years or older, moderate to severe chronic kidney disease, and high-sensitivity CRP of at least 2 mg/L. Participants were randomly allocated (1:1:1:1) to subcutaneous administration of placebo or ziltivekimab 7·5 mg, 15 mg, or 30 mg every 4 weeks up to 24 weeks. The primary outcome was percentage change from baseline in high-sensitivity CRP after 12 weeks of treatment with ziltivekimab compared with placebo, with additional biomarker and safety data collected over 24 weeks of treatment. Primary analyses were done in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of assigned treatment. The trial is registered with ClinicalTrials.gov, NCT03926117. FINDINGS: Between June 17, 2019, and Jan 14, 2020, 264 participants were enrolled into the trial, of whom 66 were randomly assigned to each of the four treatment groups. At 12 weeks after randomisation, median high-sensitivity CRP levels were reduced by 77% for the 7·5 mg group, 88% for the 15 mg group, and 92% for the 30 mg group compared with 4% for the placebo group. As such, the median pairwise differences in percentage change in high-sensitivity CRP between the ziltivekimab and placebo groups, after aligning for strata, were -66·2% for the 7·5 mg group, -77·7% for the 15 mg group, and -87·8% for the 30 mg group (all p<0·0001). Effects were stable over the 24-week treatment period. Dose-dependent reductions were also observed for fibrinogen, serum amyloid A, haptoglobin, secretory phospholipase A2, and lipoprotein(a). Ziltivekimab was well tolerated, did not affect the total cholesterol to HDL cholesterol ratio, and there were no serious injection-site reactions, sustained grade 3 or 4 neutropenia or thrombocytopenia. INTERPRETATION: Ziltivekimab markedly reduced biomarkers of inflammation and thrombosis relevant to atherosclerosis. On the basis of these data, a large-scale cardiovascular outcomes trial will investigate the effect of ziltivekimab in patients with chronic kidney disease, increased high-sensitivity CRP, and established cardiovascular disease. FUNDING: Novo Nordisk.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Proteína C-Reativa/efeitos dos fármacos , Interleucina-6/antagonistas & inibidores , Insuficiência Renal Crônica/tratamento farmacológico , Idoso , Aterosclerose , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Humanos , Inflamação/complicações , Inflamação/tratamento farmacológico , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/complicações , Trombose/complicações , Resultado do Tratamento
20.
Circ Res ; 127(8): 1094-1108, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32660330

RESUMO

RATIONALE: Circumstantial evidence links the development of heart failure to posttranslational modifications of mitochondrial proteins, including lysine acetylation (Kac). Nonetheless, direct evidence that Kac compromises mitochondrial performance remains sparse. OBJECTIVE: This study sought to explore the premise that mitochondrial Kac contributes to heart failure by disrupting oxidative metabolism. METHODS AND RESULTS: A DKO (dual knockout) mouse line with deficiencies in CrAT (carnitine acetyltransferase) and Sirt3 (sirtuin 3)-enzymes that oppose Kac by buffering the acetyl group pool and catalyzing lysine deacetylation, respectively-was developed to model extreme mitochondrial Kac in cardiac muscle, as confirmed by quantitative acetyl-proteomics. The resulting impact on mitochondrial bioenergetics was evaluated using a respiratory diagnostics platform that permits comprehensive assessment of mitochondrial function and energy transduction. Susceptibility of DKO mice to heart failure was investigated using transaortic constriction as a model of cardiac pressure overload. The mitochondrial acetyl-lysine landscape of DKO hearts was elevated well beyond that observed in response to pressure overload or Sirt3 deficiency alone. Relative changes in the abundance of specific acetylated lysine peptides measured in DKO versus Sirt3 KO hearts were strongly correlated. A proteomics comparison across multiple settings of hyperacetylation revealed ≈86% overlap between the populations of Kac peptides affected by the DKO manipulation as compared with experimental heart failure. Despite the severity of cardiac Kac in DKO mice relative to other conditions, deep phenotyping of mitochondrial function revealed a surprisingly normal bioenergetics profile. Thus, of the >120 mitochondrial energy fluxes evaluated, including substrate-specific dehydrogenase activities, respiratory responses, redox charge, mitochondrial membrane potential, and electron leak, we found minimal evidence of oxidative insufficiencies. Similarly, DKO hearts were not more vulnerable to dysfunction caused by transaortic constriction-induced pressure overload. CONCLUSIONS: The findings challenge the premise that hyperacetylation per se threatens metabolic resilience in the myocardium by causing broad-ranging disruption to mitochondrial oxidative machinery.


Assuntos
Insuficiência Cardíaca/metabolismo , Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/metabolismo , Proteoma , Acetilação , Animais , Carnitina O-Acetiltransferase/deficiência , Carnitina O-Acetiltransferase/genética , Modelos Animais de Doenças , Metabolismo Energético , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/fisiopatologia , Lisina , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo , Processamento de Proteína Pós-Traducional , Proteômica , Sirtuína 3/deficiência , Sirtuína 3/genética
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