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Lipids play crucial roles in many biological processes. Mapping spatial distributions and examining the metabolic dynamics of different lipid subtypes in cells and tissues are critical to better understanding their roles in aging and diseases. Commonly used imaging methods (such as mass spectrometry-based, fluorescence labeling, conventional optical imaging) can disrupt the native environment of cells/tissues, have limited spatial or spectral resolution, or cannot distinguish different lipid subtypes. Here we present a hyperspectral imaging platform that integrates a Penalized Reference Matching algorithm with Stimulated Raman Scattering (PRM-SRS) microscopy. Using this platform, we visualize and identify high density lipoprotein particles in human kidney, a high cholesterol to phosphatidylethanolamine ratio inside granule cells of mouse hippocampus, and subcellular distributions of sphingosine and cardiolipin in human brain. Our PRM-SRS displays unique advantages of enhanced chemical specificity, subcellular resolution, and fast data processing in distinguishing lipid subtypes in different organs and species.
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Microscopía , Microscopía Óptica no Lineal , Animales , Ratones , Humanos , Microscopía Óptica no Lineal/métodos , Espectrometría Raman/métodos , LípidosRESUMEN
Though TDP-43 protein can be translocated into mitochondria and causes mitochondrial damage in TDP-43 proteinopathy, little is known about how TDP-43 is imported into mitochondria. In addition, whether mitochondrial damage is caused by mitochondrial mislocalization of TDP-43 or a side effect of mitochondria-mediated TDP-43 degradation remains to be investigated. Here, our bioinformatical analyses reveal that mitophagy receptor gene FUNDC1 is co-expressed with TDP-43, and both TDP-43 and FUNDC1 expression is correlated with genes associated with mitochondrial protein import pathway in brain samples of patients diagnosed with TDP-43 proteinopathy. FUNDC1 promotes mitochondrial translocation of TDP-43 possibly by promoting TDP-43-TOM70 and DNAJA2-TOM70 interactions, which is independent of the LC3 interacting region of FUNDC1 in cellular experiments. In the transgenic fly model of TDP-43 proteinopathy, overexpressing FUNDC1 enhances TDP-43 induced mitochondrial damage, whereas down-regulating FUNDC1 reverses TDP-43 induced mitochondrial damage. FUNDC1 regulates mitochondria-mediated TDP-43 degradation not only by regulating mitochondrial TDP-43 import, but also by increasing LONP1 level and by activating mitophagy, which plays important roles in cytosolic TDP-43 clearance. Together, this study not only uncovers the mechanism of mitochondrial TDP-43 import, but also unravels the active role played by mitochondria in regulating TDP-43 homeostasis.
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Proteínas Mitocondriales , Proteinopatías TDP-43 , Humanos , Proteasas ATP-Dependientes/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas del Choque Térmico HSP40/metabolismo , Proteínas de la Membrana/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Mitofagia , Proteinopatías TDP-43/metabolismoRESUMEN
BACKGROUND: Eribulin, a halichondrin-class microtubule dynamics inhibitor, is a preferred treatment option for patients with advanced breast cancer who have been pretreated with an anthracycline and a taxane. Peripheral neuropathy (PN) is a common side effect of chemotherapies for breast cancer and other tumors. The Incidence and Resolution of Eribulin-Induced Peripheral Neuropathy (IRENE) noninterventional postauthorization safety study assessed the incidence and severity of PN in patients with breast cancer treated with eribulin. PATIENTS AND METHODS: IRENE is an ongoing observational, single-arm, prospective, multicenter, cohort study. Adult patients (≥18 years of age) with locally advanced or metastatic breast cancer and disease progression after 1-2 prior chemotherapeutic regimen(s) for advanced disease were treated with eribulin. Patients with eribulin-induced PN (new-onset PN or worsening of preexisting PN) were monitored until death or resolution of PN. Primary endpoints included the incidence, severity, and time to resolution of eribulin-induced PN. Secondary endpoints included time to disease progression and safety. RESULTS: In this interim analysis (data cutoff date: July 1, 2019), 67 (32.4%) patients experienced any grade eribulin-induced PN, and 12 (5.8%) patients experienced grade ≥3 eribulin-induced PN. Median time to resolution of eribulin-induced PN was not reached. Median time to disease progression was 4.6 months (95% CI, 4.0-6.5). Treatment-emergent adverse events (TEAEs) occurred in 195 (93.8%) patients and serious TEAEs occurred in 107 (51.4%) patients. CONCLUSION: The rates of any grade and grade ≥3 eribulin-induced PN observed in this real-world study were consistent with those observed in phase III randomized clinical trials. No new safety findings were observed.
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Neoplasias de la Mama , Enfermedades del Sistema Nervioso Periférico , Adulto , Femenino , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Estudios de Cohortes , Progresión de la Enfermedad , Furanos/efectos adversos , Incidencia , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/epidemiología , Estudios Prospectivos , Resultado del Tratamiento , Moduladores de Tubulina/efectos adversosRESUMEN
TDP-43 dysfunction is a molecular hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). A major hypothesis of TDP-43 dysfunction in disease is the loss of normal nuclear function, resulting in impaired RNA regulation and the emergence of cryptic exons. Cryptic exons and differential exon usage are emerging as promising markers of lost TDP-43 function in addition to revealing biological pathways involved in neurodegeneration in ALS/FTD. In this brief report, we identified markers of TDP-43 loss of function by depleting TARDBP from post-mortem human brain pericytes, a manipulable in vitro primary human brain cell model, and identifying differential exon usage events with bulk RNA-sequencing analysis. We present these data in an interactive database (https://www.scotterlab.auckland.ac.nz/research-themes/tdp43-lof-db-v2/) together with seven other TDP-43-depletion datasets we meta-analysed previously, for user analysis of differential expression and splicing signatures. Differential exon usage events that were validated by qPCR were then compiled into a 'differential exon usage panel' with other well-established TDP-43 loss-of-function exon markers. This differential exon usage panel was investigated in ALS and control motor cortex tissue to verify whether, and to what extent, TDP-43 loss of function occurs in ALS. We find that profiles of TDP-43-regulated cryptic exons, changed exon usage and changed 3' UTR usage discriminate ALS brain tissue from controls, verifying that TDP-43 loss of function occurs in ALS. We propose that TDP-43-regulated splicing events that occur in brain tissue will have promise as predictors of disease.
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Esclerosis Amiotrófica Lateral , Proteínas de Unión al ADN , Demencia Frontotemporal , Humanos , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Encéfalo/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Demencia Frontotemporal/genética , ARN , Empalme del ARNRESUMEN
Objective This study describes how a model of early rehabilitation ('in-reach rehabilitation') can be integrated into acute care provision for hospitalised patients with high rehabilitation needs. This pragmatic evaluation aimed to assess service impact on home discharge rates from acute care. Methods An integrated early rehabilitation service was implemented at a tertiary teaching hospital in Sydney, Australia. Eligible patients were screened, placed on a waitlist, and treated in order of debility (six to eight patients concurrently). Routine data were collected and compared between those who received an in-reach rehabilitation program, and controls who remained on waitlist. Results From December 2021 to September 2022, 229 patients were identified as suitable for in-reach rehabilitation; of whom 100 received an in-reach program and the remaining 129 were waitlist controls. Patients who received in-reach rehabilitation achieved a significantly higher rate of discharge home from acute care compared to waitlist controls (46.0% vs 24.0%, P = 0.002) and lower rates of transfer to subacute inpatient rehabilitation (43.0% vs 62.0%). This was despite in-reach patients having high functional care needs (60% needed assistance from ≥two people to mobilise) and complex medical needs (median hospital length of stay 44.5 days, IQR 27.8-66.0). Conclusions It is feasible to deliver in-reach rehabilitation to hospitalised patients with heterogeneous diagnoses who have high rehabilitation needs. The rate of discharge home directly from acute wards is higher among those patients who received early in-reach rehabilitation compared to those on a waitlist.
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Studies have shown that brain lipid metabolism is associated with biological aging and influenced by dietary and genetic manipulations; however, the underlying mechanisms are elusive. High-resolution imaging techniques propose a novel and potent approach to understanding lipid metabolic dynamics in situ. Applying deuterium water (D2O) probing with stimulated Raman scattering (DO-SRS) microscopy, we revealed that lipid metabolic activity in Drosophila brain decreased with aging in a sex-dependent manner. Female flies showed an earlier occurrence of lipid turnover decrease than males. Dietary restriction (DR) and downregulation of insulin/IGF-1 signaling (IIS) pathway, two scenarios for lifespan extension, led to significant enhancements of brain lipid turnover in old flies. Combining SRS imaging with deuterated bioorthogonal probes (deuterated glucose and deuterated acetate), we discovered that, under DR treatment and downregulation of IIS pathway, brain metabolism shifted to use acetate as a major carbon source for lipid synthesis. For the first time, our study directly visualizes and quantifies spatiotemporal alterations of lipid turnover in Drosophila brain at the single organelle (lipid droplet) level. Our study not only demonstrates a new approach for studying brain lipid metabolic activity in situ but also illuminates the interconnection of aging, dietary, and genetic manipulations on brain lipid metabolic regulation.
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In this study, polyethylene oxide (PEO) and curdlan solutions were used to prepare PEO/curdlan nanofiber films by electrospinning using deionized water as the solvent. In the electrospinning process, PEO was used as the base material, and its concentration was fixed at 6.0 wt.%. Moreover, the concentration of curdlan gum varied from 1.0 to 5.0 wt.%. For the electrospinning conditions, various operating voltages (12-24 kV), working distances (12-20 cm) and feeding rates of polymer solution (5-50 µL/min) were also modified. Based on the experimental results, the optimum concentration for the curdlan gum was 2.0 wt.%. Additionally, the most suitable operating voltage, working distance and feeding rate for the electrospinning process were 19 kV, 20 cm and 9 µL/min, respectively, which can help to prepare relatively thinner PEO/curdlan nanofibers with higher mesh porosity and without the formation of beaded nanofibers. Finally, the PEO/curdlan nanofiber instant films containing 5.0 wt.% quercetin inclusion complex were used to perform wetting and disintegration processes. It was found that the instant film can be dissolved significantly on the low-moisture wet wipe. On the other hand, when the instant film touched water, it can be disintegrated very quickly within 5 s, and the quercetin inclusion complex was dissolved in water efficiently. Furthermore, when the instant film encountered the water vapor at 50 °C, it almost completely disintegrated after immersion for 30 min. The results indicate that the electrospun PEO/curdlan nanofiber film is highly feasible for biomedical applications consisting of instant masks and quick-release wound dressings, even in the water vapor environment.
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Neurons migrate from their birthplaces to the destinations, and extending axons navigate to their synaptic targets by sensing various extracellular cues in spatiotemporally controlled manners. These evolutionally conserved guidance cues and their receptors regulate multiple aspects of neural development to establish the highly complex nervous system by mediating both short- and long-range cell-cell communications. Neuronal guidance genes (encoding cues, receptors, or downstream signal transducers) are critical not only for development of the nervous system but also for synaptic maintenance, remodeling, and function in the adult brain. One emerging theme is the combinatorial and complementary functions of relatively limited classes of neuronal guidance genes in multiple processes, including neuronal migration, axonal guidance, synaptogenesis, and circuit formation. Importantly, neuronal guidance genes also regulate cell migration and cell-cell communications outside the nervous system. We are just beginning to understand how cells integrate multiple guidance and adhesion signaling inputs to determine overall cellular/subcellular behavior and how aberrant guidance signaling in various cell types contributes to diverse human diseases, ranging from developmental, neuropsychiatric, and neurodegenerative disorders to cancer metastasis. We review classic studies and recent advances in understanding signaling mechanisms of the guidance genes as well as their roles in human diseases. Furthermore, we discuss the remaining challenges and therapeutic potentials of modulating neuronal guidance pathways in neural repair.
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Orientación del Axón , Neuronas , Humanos , Orientación del Axón/genética , Axones/metabolismo , Transducción de Señal/genética , Comunicación CelularRESUMEN
Stimulated Raman scattering (SRS) offers the ability to image metabolic dynamics with high signal-to-noise ratio. However, its spatial resolution is limited by the numerical aperture of the imaging objective and the scattering cross-section of molecules. To achieve super-resolved SRS imaging, we developed a deconvolution algorithm, adaptive moment estimation (Adam) optimization-based pointillism deconvolution (A-PoD) and demonstrated a spatial resolution of lower than 59 nm on the membrane of a single lipid droplet (LD). We applied A-PoD to spatially correlated multiphoton fluorescence imaging and deuterium oxide (D2O)-probed SRS (DO-SRS) imaging from diverse samples to compare nanoscopic distributions of proteins and lipids in cells and subcellular organelles. We successfully differentiated newly synthesized lipids in LDs using A-PoD-coupled DO-SRS. The A-PoD-enhanced DO-SRS imaging method was also applied to reveal metabolic changes in brain samples from Drosophila on different diets. This new approach allows us to quantitatively measure the nanoscopic colocalization of biomolecules and metabolic dynamics in organelles.
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Microscopía , Espectrometría Raman , Microscopía/métodos , Espectrometría Raman/métodos , Proteínas/metabolismo , LípidosRESUMEN
PURPOSE: Professional interpreters can improve healthcare quality and outcomes when there is language discordance between patients and health care providers. Multidisciplinary rehabilitation relies on nuanced communication; however, the use of interpreters in rehabilitation is underexplored. This study aimed to examine patterns of health care interpreter use in an inpatient rehabilitation setting. METHODS: A retrospective cohort study was conducted including patients admitted for subacute rehabilitation during 2019-2020 identified as having limited English proficiency. Patterns of interpreter use (professional and "ad hoc") and rehabilitation outcomes were evaluated via medical record review. RESULTS: Eighty-five participants were included. During inpatient rehabilitation (median 17 [12-28] days), most clinical interactions (95%) occurred without an interpreter present. Patterns of interpreter use were variable; with greater use of ad hoc versus professional interpreters (received by 60% versus 49% of the cohort, respectively). Those who interacted with a professional interpreter had a longer length-of-stay, larger Functional Independence Measure (FIM) gain, and lower rate of hospital readmission six months post-discharge. The number of professional interpreter sessions correlated positively with FIM gain. CONCLUSIONS: Access to professional interpreters in inpatient rehabilitation was variable, with some patients having no or minimal access. These findings provide preliminary evidence that professional interpreter use may be associated with clinical rehabilitation outcomes. Implications for rehabilitationProfessional health care interpreters can be used to overcome language barriers in rehabilitation.In an inpatient rehabilitation setting, professional interpreters appeared to be underutilized, with many patients having no or minimal access to interpreters.Use of ad hoc, untrained interpreters and informal communication strategies was common during rehabilitation.Use of professional interpreters appeared to be associated with favorable rehabilitation outcomes.
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Cuidados Posteriores , Pacientes Internos , Humanos , Estudios Retrospectivos , Alta del Paciente , Barreras de Comunicación , Atención a la Salud , TraducciónRESUMEN
Amyotrophic lateral sclerosis (ALS) is a fatal movement disorder involving degeneration of motor neurons through dysfunction of the RNA-binding protein TDP-43. Pericytes, the perivascular cells of the blood-brain, blood-spinal cord, and blood-CSF barriers also degenerate in ALS. Indeed, pericytes are among the earliest cell types to show gene expression changes in pre-symptomatic animal models of ALS. This suggests that pericyte degeneration precedes neurodegeneration and may involve pericyte cell-autonomous TDP-43 dysfunction. Here we determined the effect of TDP-43 dysfunction in human brain pericytes on interleukin 6 (IL-6), a critical secreted inflammatory mediator reported to be regulated by TDP 43. Primary human brain pericytes were cultured from biopsy tissue from epilepsy surgeries and TDP-43 was silenced using siRNA. TDP-43 silencing of pericytes stimulated with pro-inflammatory cytokines, interleukin-1ß or tumour necrosis factor alpha, robustly suppressed the induction of IL-6 transcript and protein. IL-6 regulation by TDP-43 did not involve the assembly of TDP-43 nuclear splicing bodies, and did not occur via altered splicing of IL6. Instead, transcriptome-wide analysis by RNA-Sequencing identified a poison exon in the IL6 destabilising factor HNRNPD (AUF1) as a splicing target of TDP-43. Our data support a model whereby TDP-43 silencing favours destabilisation of IL6 mRNA, via enhanced AU-rich element-mediated decay by HNRNP/AUF1. This suggests that cell-autonomous deficits in TDP-43 function in human brain pericytes would suppress their production of IL-6. Given the importance of the blood-brain and blood-spinal cord barriers in maintaining motor neuron health, TDP-43 in human brain pericytes may represent a cellular target for ALS therapeutics.
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Esclerosis Amiotrófica Lateral , Proteínas de Unión al ADN , Interleucina-6 , Pericitos , Humanos , Esclerosis Amiotrófica Lateral/metabolismo , Encéfalo/metabolismo , Citocinas/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Expresión Génica , Interleucina-6/metabolismo , Pericitos/metabolismo , Pericitos/patología , Médula Espinal/metabolismoRESUMEN
MOTIVATION: Alternative splicing is an important mechanism to generate transcriptomic and phenotypic diversity. Existing methods have limited power to detect orthologous isoforms. RESULTS: We develop a new method, EGIO, to detect orthologous exons and orthologous isoforms from two species. EGIO uses unique exonic regions to construct exon groups, in which process dynamic programming strategy is used to do exon alignment. EGIO could cover all the coding exons within orthologous genes. A comparison between EGIO and ExTraMapper shows that EGIO could detect more orthologous isoforms with conserved sequence and exon structures. We apply EGIO to compare human and chimpanzee protein-coding isoforms expressed in the frontal cortex and identify 6912 genes that express human unique isoforms. Unexpectedly, more human unique isoforms are detected than those conserved between humans and chimpanzees. AVAILABILITY AND IMPLEMENTATION: Source code and test data of EGIO are available at https://github.com/wu-lab-egio/EGIO. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Empalme Alternativo , Programas Informáticos , Humanos , Exones , Isoformas de Proteínas/genética , Secuencia ConservadaRESUMEN
Platelet-derived growth factor-BB (PDGF-BB):PDGF receptor-ß (PDGFRß) signalling in brain pericytes is critical to the development, maintenance and function of a healthy blood-brain barrier (BBB). Furthermore, BBB impairment and pericyte loss in Alzheimer's disease (AD) is well documented. We found that PDGF-BB:PDGFRß signalling components were altered in human AD brains, with a marked reduction in vascular PDGFB. We hypothesised that reduced PDGF-BB:PDGFRß signalling in pericytes may impact on the BBB. We therefore tested the effects of PDGF-BB on primary human brain pericytes in vitro to define pathways related to BBB function. Using pharmacological inhibitors, we dissected distinct aspects of the PDGF-BB response that are controlled by extracellular signal-regulated kinase (ERK) and Akt pathways. PDGF-BB promotes the proliferation of pericytes and protection from apoptosis through ERK signalling. In contrast, PDGF-BB:PDGFRß signalling through Akt augments pericyte-derived inflammatory secretions. It may therefore be possible to supplement PDGF-BB signalling to stabilise the cerebrovasculature in AD.
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Enfermedad de Alzheimer , Pericitos , Enfermedad de Alzheimer/metabolismo , Becaplermina/metabolismo , Becaplermina/farmacología , Encéfalo/metabolismo , Humanos , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/farmacologíaRESUMEN
BACKGROUND: Despite advances in the first-line treatment of metastatic renal cell carcinoma (RCC), there is an unmet need for options to address disease progression during or after treatment with immune checkpoint inhibitors (ICIs). Pembrolizumab and lenvatinib are active as monotherapies in RCC; thus, we aimed to evaluate the combination of lenvatinib plus pembrolizumab in these patients. METHODS: We report results of the metastatic RCC cohort from an open-label phase 1b/2 study of lenvatinib plus pembrolizumab in patients aged at least 18 years with selected solid tumours and an Eastern Cooperative Oncology Group performance status of 0-1. Oral lenvatinib at 20 mg was given once daily along with intravenous pembrolizumab at 200 mg once every 3 weeks. Patients remained on study drug treatment until disease progression, development of unacceptable toxicity, or withdrawal of consent. Efficacy was analysed in patients with clear cell metastatic RCC receiving study drug by previous therapy grouping: treatment naive, previously treated ICI naive (previously treated with at least one line of therapy but not with an anti-PD-1 or anti-PD-L1 ICI), and ICI pretreated (ie, anti-PD-1 or anti-PD-L1) patients. Safety was analysed in all enrolled and treated patients. The primary endpoint was the objective response rate at week 24 per immune-related Response Evaluation Criteria In Solid Tumors (irRECIST) by investigator assessment. This trial is registered with ClinicalTrials.gov (NCT02501096) and with the EU Clinical Trials Register (EudraCT2017-000300-26), and is closed to new participants. FINDINGS: Between July 21, 2015, and Oct 16, 2019, 145 patients were enrolled in the study. Two patients had non-clear cell RCC and were excluded from the efficacy analysis (one in the treatment-naive group and one in the ICI-pretreated group); thus, the population evaluated for efficacy comprised 143 patients (n=22 in the treatment-naive group, n=17 in the previously treated ICI-naive group, and n=104 in the ICI-pretreated group). All 145 enrolled patients were included in the safety analysis. The median follow-up was 19·8 months (IQR 14·3-28·4). The number of patients with an objective response at week 24 by irRECIST was 16 (72·7%, 95% CI 49·8-89·3) of 22 treatment-naive patients, seven (41·2%, 18·4-67·1) of 17 previously treated ICI-naive patients, and 58 (55·8%, 45·7-65·5) of 104 ICI-pretreated patients. Of 145 patients, 82 (57%) had grade 3 treatment-related adverse events and ten (7%) had grade 4 treatment-related adverse events. The most common grade 3 treatment-related adverse event was hypertension (30 [21%] of 145 patients). Treatment-related serious adverse events occurred in 36 (25%) patients, and there were three treatment-related deaths (upper gastrointestinal haemorrhage, sudden death, and pneumonia). INTERPRETATION: Lenvatinib plus pembrolizumab showed encouraging antitumour activity and a manageable safety profile and might be an option for post-ICI treatment of metastatic RCC. FUNDING: Eisai and Merck Sharp & Dohme.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinolinas/uso terapéutico , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Renales/inmunología , Carcinoma de Células Renales/secundario , Europa (Continente) , Femenino , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Neoplasias Renales/inmunología , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Compuestos de Fenilurea/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Quinolinas/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Estados UnidosRESUMEN
Tunneling nanotubes (TNTs) are actin-rich structures that connect two or more cells and mediate cargo exchange between spatially separated cells. TNTs transport signaling molecules, vesicles, organelles, and even pathogens. However, the molecular mechanisms regulating TNT formation remain unclear and little is known about the endogenous mechanisms suppressing TNT formation in lung cancer cells. Here, we report that MICAL2PV, a splicing isoform of the neuronal guidance gene MICAL2, is a novel TNT regulator that suppresses TNT formation and modulates mitochondrial distribution. MICAL2PV interacts with mitochondrial Rho GTPase Miro2 and regulates subcellular mitochondrial trafficking. Moreover, down-regulation of MICAL2PV enhances survival of cells treated with chemotherapeutical drugs. The monooxygenase (MO) domain of MICAL2PV is required for its activity to inhibit TNT formation by depolymerizing F-actin. Our data demonstrate a previously unrecognized function of MICAL2 in TNT formation and mitochondrial trafficking. Furthermore, our study uncovers a role of the MICAL2PV-Miro2 axis in mitochondrial trafficking, providing a mechanistic explanation for MICAL2PV activity in suppressing TNT formation and in modulating mitochondrial subcellular distribution.
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Comunicación Celular , Nanotubos , Citoesqueleto de Actina , Actinas/genética , Humanos , Proteínas de Microfilamentos , Orgánulos , OxidorreductasasRESUMEN
Rehabilitation programmes can be delivered to patients receiving acute care ('in-reach rehabilitation') and/or those who have completed acute care but experience ongoing functional impairments ('subacute rehabilitation'). Access to these programmes depends on a rehabilitation assessment, but there are concerns that referrals for this assessment are often triggered too late in the acute care journey. We describe a Proactive Rehabilitation Screening (PReS) process designed to systematically screen patients during an acute hospital admission, and identify early those who are likely to require specialist rehabilitation assessment and intervention. The process is based on review of patient medical records on day 5 after acute hospital admission, or day 3 after transfer from intensive care to an acute hospital ward. Screening involves brief review of documented care needs, pre-existing and new functional disabilities, the need for allied health interventions and non-medical factors delaying discharge. From May 2017 to February 2019, the novel screening process was implemented as part of a service redesign of the rehabilitation consultation service. Four thousand consecutive screens were performed at the study site. Of those 'ruled in' by screening as needing a rehabilitation assessment, 86.0% went on to receive inpatient rehabilitation interventions. Of those 'ruled out' by screening, 92.1% did not go on to receive a rehabilitation intervention, while 7.9% did receive some form of rehabilitation intervention. Of all patients accepted into a rehabilitation programme (n=516), PReS was able to identify 53.6% (n=282) of them before the acute care teams made a referral (based on traditional criteria). In conclusion, we have designed and implemented a systematic, PReS service in one metropolitan Australian hospital. The process described was found to be time efficient and feasible to implement in an acute hospital setting. Further, it appeared to identify the majority of patients who went on to receive formal inpatient rehabilitation interventions.
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Hospitalización , Alta del Paciente , Australia , Cuidados Críticos , Humanos , Derivación y ConsultaRESUMEN
This study was designed to evaluate the anti-inflammatory effects of Alpinia officinarum Hance extract (AOE) and identify its main active ingredients. AOE was obtained using a 95% ethanol extraction method. Lipopolysaccharide (LPS) were used to induce an inflammatory response in RAW264.7 cells. The results showed that AOE exerts anti-inflammatory effects via inhibition of prostaglandin E2 secretion and cyclooxygenase -2 (COX-2) production. We further analyzed the components of AOE using high-performance liquid chromatography and found that AOE is comprised of several bioactive flavonoids including quercetin (Q), kaempferol (K), galangin (G), and curcumin (C). These four flavonoids effectively inhibited nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α production. Moreover, they reduced COX-2 and inducible NO synthase expressions via regulation of nuclear factor kappa-light-chain-enhancer of activated B cells and c-Jun N-terminal kinase signaling pathways. Furthermore, we compared and contrasted the anti-inflammatory effects and mechanisms of these four flavonoids at the same dose in the LPS-induced cell inflammation model. The results showed that C is the most effective inhibitor of LPS-induced NO production. However, only Q and K effectively attenuated LPS-induced extracellular signal-regulated kinase and p38 elevations. In conclusion, AOE and its major bioactive compounds exert anti-inflammatory effects on LPS-induced inflammation. As A. officinarum Hance is much cheaper than any of its four flavonoids, especially G, we suggest using AOE as an anti-inflammatory agent.
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Alpinia , FN-kappa B , Alpinia/metabolismo , Animales , Antiinflamatorios/farmacología , Ciclooxigenasa 2 , Lipopolisacáridos , Macrófagos , Ratones , FN-kappa B/metabolismo , Óxido Nítrico , Óxido Nítrico Sintasa de Tipo IIRESUMEN
Emerging studies have shown that lipids and proteins play versatile roles in various aspects of aging. High-resolution in situ optical imaging provides a powerful approach to study the metabolic dynamics of lipids and proteins during aging. Here, we integrated D2O probing and stimulated Raman scattering (DO-SRS) microscopy to directly visualize metabolic changes in aging Drosophila ovary. The subcellular spatial distribution of de novo protein synthesis and lipogenesis in ovary was quantitatively imaged and examined. Our Raman spectra showed that early stages follicles were protein-enriched whereas mature eggs were lipid-enriched. DO-SRS imaging showed a higher protein synthesis in the earlier developing stages and an increased lipid turned over at the late stage. Aged (35 days) flies exhibited a dramatic decrease in metabolic turnover activities of both proteins and lipids, particularly, in the germ stem cell niche of germarium. We found an accumulation of unsaturated lipids in the nurse cells and oocytes in old flies, suggesting that unsaturated lipids may play an important role in the processes of oocyte maturation. We further detected changes in mitochondrial morphology and accumulation of Cytochrome c during aging. To our knowledge, this is the first study that directly visualizes spatiotemporal changes in lipid and protein metabolism in Drosophila ovary during development and aging processes. Our study not only demonstrates the application of a new imaging platform in visualizing metabolic dynamics of lipids and proteins in situ but also unravels how the metabolic activity and lipid distribution change in Drosophila ovary during aging.
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Macropinocytosis is essential for myeloid cells to survey their environment and for growth of RAS-transformed cancer cells. Several growth factors and inflammatory stimuli are known to induce macropinocytosis, but its endogenous inhibitors have remained elusive. Stimulation of Roundabout receptors by Slit ligands inhibits directional migration of many cell types, including immune cells and cancer cells. We report that SLIT2 inhibits macropinocytosis in vitro and in vivo by inducing cytoskeletal changes in macrophages. In mice, SLIT2 attenuates the uptake of muramyl dipeptide, thereby preventing NOD2-dependent activation of NF-κB and consequent secretion of pro-inflammatory chemokine, CXCL1. Conversely, blocking the action of endogenous SLIT2 enhances CXCL1 secretion. SLIT2 also inhibits macropinocytosis in RAS-transformed cancer cells, thereby decreasing their survival in nutrient-deficient conditions which resemble tumor microenvironment. Our results identify SLIT2 as a physiological inhibitor of macropinocytosis and challenge the conventional notion that signals that enhance macropinocytosis negatively regulate cell migration, and vice versa.