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The legume albumin-1 gene family, arising after nodulation, encodes linear a- and b-chain peptides for nutrient storage and defense. Intriguingly, in one prominent legume, Clitoria ternatea, the b-chains are replaced by domains producing ultra-stable cyclic peptides called cyclotides. The mechanism of this gene hijacking is until now unknown. Cyclotides require recruitment of ligase-type asparaginyl endopeptidases (AEPs) for maturation (cyclization), necessitating co-evolution of two gene families. Here we compare a chromosome-level C. ternatea genome with grain legumes to reveal an 8 to 40-fold expansion of the albumin-1 gene family, enabling the additional loci to undergo diversification. Iterative rounds of albumin-1 duplication and diversification create four albumin-1 enriched genomic islands encoding cyclotides, where they are physically grouped by similar pI and net charge values. We identify an ancestral hydrolytic AEP that exhibits neofunctionalization and multiple duplication events to yield two ligase-type AEPs. We propose cyclotides arise by convergence in C. ternatea where their presence enhances defense from biotic attack, thus increasing fitness compared to lineages with linear b-chains and ultimately driving the replacement of b-chains with cyclotides.
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Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Clitoria/metabolismo , Clitoria/genética , Ciclotídeos/genética , Ciclotídeos/química , Ciclotídeos/metabolismo , Fixação de Nitrogênio/genética , Evolução Molecular , Ciclização , Filogenia , Família Multigênica , Duplicação Gênica , Fabaceae/genética , Fabaceae/metabolismo , Albuminas/metabolismo , Albuminas/genética , Genoma de Planta , Cisteína EndopeptidasesRESUMO
BACKGROUND: Inadvertent intra-arterial injection of sclerosants is an uncommon adverse event of both ultrasound-guided and direct vision sclerotherapy. This complication can result in significant tissue or limb loss and significant long-term morbidity. OBJECTIVES: To provide recommendations for diagnosis and immediate management of an unintentional intra-arterial injection of sclerosing agents. METHODS: An international and multidisciplinary expert panel representing the endorsing societies and relevant specialities reviewed the published biomedical, scientific and legal literature and developed the consensus-based recommendations. RESULTS: Actual and suspected cases of an intra-arterial sclerosant injection should be immediately transferred to a facility with a vascular/interventional unit. Digital Subtraction Angiography (DSA) is the key investigation to confirm the diagnosis and help select the appropriate intra-arterial therapy for tissue ischaemia. Emergency endovascular intervention will be required to manage the risk of major limb ischaemia. This includes intra-arterial administration of vasodilators to reduce vasospasm, and anticoagulants and thrombolytic agents to mitigate thrombosis. Mechanical thrombectomy, other endovascular interventions and even open surgery may be required. Lumbar sympathetic block may be considered but has a high risk of bleeding. Systemic anti-inflammatory agents, anticoagulants, and platelet inhibitors and modifiers would complement the intra-arterial endovascular procedures. For risk of minor ischaemia, systemic oral anti-inflammatory agents, anticoagulants, vasodilators and antiplatelet treatments are recommended. CONCLUSION: Inadvertent intra-arterial injection is an adverse event of both ultrasound-guided and direct vision sclerotherapy. Medical practitioners performing sclerotherapy must ensure completion of a course of formal training (specialty or subspecialty training, or equivalent recognition) in the management of venous and lymphatic disorders (phlebology), and be personally proficient in the use of duplex ultrasound in vascular (both arterial and venous) applications, to diagnose and provide image guidance to venous procedure. Expertise in diagnosis and immediate management of an intra-arterial injection is essential for all practitioners performing sclerotherapy.
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Three-dimensional (3D) printing with polycarbonate (PC) plastic occurs in manufacturing settings, homes, and schools. Emissions generated during printing with PC stock and bisphenol-A (BPA), an endocrine disrupter in PC, may induce adverse health effects. Inhalation of 3D printer emissions, and changes in endocrine function may lead to cardiovascular dysfunction. The goal of this study was to determine whether there were any changes in markers of peripheral or cardiovascular dysfunction in animals exposed to PC-emissions. Male Sprague Dawley rats were exposed to PC-emissions generated by 3D printing for 1, 4, 8, 15 or 30 d. Exposure induced a reduction in the expression of the antioxidant catalase (Cat) and endothelial nitric oxide synthase (eNos). Endothelin and hypoxia-induced factor 1α transcripts increased after 30 d. Alterations in transcription were associated with elevations in immunostaining for estrogen and androgen receptors, nitrotyrosine, and vascular endothelial growth factor in cardiac arteries of PC-emission exposed animals. There was also a reduction eNOS immunostaining in cardiac arteries from rats exposed to PC-emissions. Histological analyses of heart sections revealed that exposure to PC-emissions resulted in vasoconstriction of cardiac arteries and thickening of the vascular smooth muscle wall, suggesting there was a prolonged vasoconstriction. These findings are consistent with studies showing that inhalation 3D-printer emissions affect cardiovascular function. Although BPA levels in animals were relatively low, exposure-induced changes in immunostaining for estrogen and androgen receptors in cardiac arteries suggest that changes in the action of steroid hormones may have contributed to the alterations in morphology and markers of cardiac function.
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Estresse Oxidativo , Cimento de Policarboxilato , Impressão Tridimensional , Ratos Sprague-Dawley , Animais , Masculino , Ratos , Estresse Oxidativo/efeitos dos fármacos , Biomarcadores/metabolismo , Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Miocárdio/metabolismo , Poluentes Atmosféricos/toxicidade , Coração/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismoRESUMO
PURPOSE: Glioblastoma (GBM) is a lethal brain tumor. Standard-of-care treatment comprising surgery, radiation, and chemotherapy results in median survival rates of 12 to 15 months. Molecular-targeted agents identified using conventional 2-dimensional (2D) in vitro models of GBM have failed to improve outcome in patients, rendering such models inadequate for therapeutic target identification. A previously developed 3D GBM in vitro model that recapitulates key GBM clinical features and responses to molecular therapies was investigated for utility for screening novel radiation-drug combinations using gold-standard clonogenic survival as readout. METHODS AND MATERIALS: Patient-derived GBM cell lines were optimized for inclusion in a 96-well plate 3D clonogenic screening platform, ClonoScreen3D. Radiation responses of GBM cells in this system were highly reproducible and comparable to those observed in low-throughout 3D assays. The screen methodology provided quantification of candidate drug single agent activity (half maximal effective concentration or EC50) and the interaction between drug and radiation (radiation interaction ratio). RESULTS: The poly(ADP-ribose) polymerase inhibitors talazoparib, rucaparib, and olaparib each showed a significant interaction with radiation by ClonoScreen3D and were subsequently confirmed as true radiosensitizers by full clonogenic assay. Screening a panel of DNA damage response inhibitors revealed the expected propensity of these compounds to interact significantly with radiation (13/15 compounds). A second screen assessed a panel of compounds targeting pathways identified by transcriptomic analysis and demonstrated single agent activity and a previously unreported interaction with radiation of dinaciclib and cytarabine (radiation interaction ratio 1.28 and 1.90, respectively). These compounds were validated as radiosensitizers in full clonogenic assays (sensitizer enhancement ratio 1.47 and 1.35, respectively). CONCLUSIONS: The ClonoScreen3D platform was demonstrated to be a robust method to screen for single agent and radiation-drug combination activity. Using gold-standard clonogenicity, this assay is a tool for identification of radiosensitizers. We anticipate this technology will accelerate identification of novel radiation-drug combinations with genuine translational value.
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Neoplasias Encefálicas , Glioblastoma , Ftalazinas , Inibidores de Poli(ADP-Ribose) Polimerases , Radiossensibilizantes , Glioblastoma/radioterapia , Glioblastoma/patologia , Humanos , Radiossensibilizantes/farmacologia , Linhagem Celular Tumoral , Ftalazinas/farmacologia , Ftalazinas/uso terapêutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Indóis/farmacologia , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Reprodutibilidade dos Testes , Técnicas de Cultura de Células em Três Dimensões/métodosRESUMO
Plexiform neurofibromas (PNFs) are nerve tumors caused by loss of NF1 and dysregulation of RAS-MAPK signaling in Schwann cells. Most PNFs shrink in response to MEK inhibition, but targets with increased and durable effects are needed. We identified the anaphylatoxin C5a as increased in PNFs and expressed largely by PNF m acrophages. We defined pharmacokinetic and immunomodulatory properties of a C5aR1/2 antagonist and tested if peptide antagonists augment the effects of MEK inhibition. MEK inhibition recruited C5AR1 to the macrophage surface; short-term inhibition of C5aR elevated macrophage apoptosis and Schwann cell death, without affecting MEK-induced tumor shrinkage. PNF macrophages lacking C5aR1 increased the engulfment of dying Schwann cells, allowing their visualization. Halting combination therapy resulted in altered T-cell distribution, elevated Iba1+ and CD169+ immunoreactivity, and profoundly altered cytokine expression, but not sustained trumor shrinkage. Thus, C5aRA inhibition independently induces macrophage cell death and causes sustained and durable effects on the PNF microenvironment.
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Citofagocitose , Neurofibroma Plexiforme , Humanos , Macrófagos/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Neurofibroma Plexiforme/patologia , Transdução de Sinais , Microambiente TumoralRESUMO
PURPOSE: Patients with glioblastoma who are older or have poor performance status (PS) experience particularly poor clinical outcomes. At the time of study initiation, these patients were treated with short-course radiation therapy (40 Gy in 15 fractions). Olaparib is an oral inhibitor of the DNA repair enzyme poly (ADP-ribose) polymerase (PARP) that is well tolerated as a single agent but exacerbates acute radiation toxicity in extracranial sites. Preclinical data predicted that PARP inhibitors would enhance radiosensitivity in glioblastoma without exacerbating adverse effects on the normal brain. METHODS AND MATERIALS: Phase 1 of the PARADIGM trial was a 3+3 dose-escalation study testing olaparib in combination with radiation therapy (40 Gy 15 fractions) in patients with newly diagnosed glioblastoma who were unsuitable for radical treatment either because they were aged 70 years or older (World Health Organization PS 0-1) or aged 18 to 69 years with PS 2. The primary outcome was the recommended phase 2 dose of olaparib. Secondary endpoints included safety and tolerability, overall survival, and progression-free survival. Effects on cognitive function were assessed via the Mini Mental State Examination. RESULTS: Of 16 eligible patients (56.25% male; median age, 71.5 years [range, 44-78]; 75% PS 0-1), 1 dose-limiting toxicity was reported (grade 3 agitation). Maximum tolerated dose was not reached and the recommended phase 2 dose was determined as 200 mg twice daily. Median overall survival and progression-free survival were 10.8 months (80% CI, 7.3-11.4) and 5.5 months (80% CI, 3.9-5.9), respectively. Mini Mental State Examination plots indicated that cognitive function was not adversely affected by the olaparib-radiation therapy combination. CONCLUSIONS: Olaparib can be safely combined with hypofractionated brain radiation therapy and is well tolerated in patients unsuitable for radical chemoradiation. These results enabled initiation of a randomized phase 2 study and support future trials of PARP inhibitors in combination with radiation therapy for patients with brain tumors.
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Neoplasias Encefálicas , Glioblastoma , Piperazinas , Humanos , Masculino , Idoso , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Ftalazinas/efeitos adversosRESUMO
BACKGROUND: Glioblastomas have highly infiltrative growth patterns that contribute to recurrence and poor survival. Despite infiltration being a critical therapeutic target, no clinically useful therapies exist that counter glioblastoma invasion. Here, we report that inhibition of ataxia telangiectasia and Rad 3 related kinase (ATR) reduces invasion of glioblastoma cells through dysregulation of cytoskeletal networks and subsequent integrin trafficking. METHODS: Glioblastoma motility and invasion were assessed in vitro and in vivo in response to ATR inhibition (ATRi) and ATR overexpression using time-lapse microscopy, two orthotopic glioblastoma models, and intravital imaging. Disruption to cytoskeleton networks and endocytic processing were investigated via high-throughput, super-resolution and intravital imaging. RESULTS: High ATR expression was associated with significantly poorer survival in clinical datasets while histological, protein expression, and spatial transcriptomics using glioblastoma tumor specimens revealed higher ATR expression at infiltrative margins. Pharmacological inhibition with two different compounds and RNAi targeting of ATR opposed the invasion of glioblastoma, whereas overexpression of ATR drove migration. Subsequent investigation revealed that cytoskeletal dysregulation reduced macropinocytotic internalization of integrins at growth-cone-like structures, resulting in a tumor microtube retraction defect. The biological relevance and translational potential of these findings were confirmed using two orthotopic in vivo models of glioblastoma and intravital imaging. CONCLUSIONS: We demonstrate a novel role for ATR in determining invasion in glioblastoma cells and propose that pharmacological targeting of ATR could have far-reaching clinical benefits beyond radiosensitization.
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Glioblastoma , Humanos , Glioblastoma/patologia , Integrinas/metabolismo , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Invasividade Neoplásica , Proteínas Mutadas de Ataxia Telangiectasia/metabolismoRESUMO
Patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) frequently present with advanced metastatic disease and exhibit a poor response to therapy, resulting in poor outcomes. The tumor microenvironment cytokine Oncostatin-M (OSM) initiates PDAC plasticity, inducing the reprogramming to a stem-like/mesenchymal state, which enhances metastasis and therapy resistance. Using a panel of PDAC cells driven through epithelial-mesenchymal transition (EMT) by OSM or the transcription factors ZEB1 or SNAI1, we find that OSM uniquely induces tumor initiation and gemcitabine resistance independently of its ability to induce a CD44HI/mesenchymal phenotype. In contrast, while ZEB1 and SNAI1 induce a CD44HI/mesenchymal phenotype and migration comparable with OSM, they are unable to promote tumor initiation or robust gemcitabine resistance. Transcriptomic analysis identified that OSM-mediated stemness requires MAPK activation and sustained, feed-forward transcription of OSMR. MEK and ERK inhibitors prevented OSM-driven transcription of select target genes and stem-like/mesenchymal reprogramming, resulting in reduced tumor growth and resensitization to gemcitabine. We propose that the unique properties of OSMR, which hyperactivates MAPK signaling when compared with other IL6 family receptors, make it an attractive therapeutic target, and that disrupting the OSM-OSMR-MAPK feed-forward loop may be a novel way to therapeutically target the stem-like behaviors common to aggressive PDAC. IMPLICATIONS: Small-molecule MAPK inhibitors may effectively target the OSM/OSMR-axis that leads to EMT and tumor initiating properties that promote aggressive PDAC.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Receptores de Oncostatina M , Transdução de Sinais , Oncostatina M/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Transição Epitelial-Mesenquimal , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Microambiente TumoralRESUMO
Multiple sclerosis (MS) is a debilitating disease that requires prolonged treatment with often severe side effects. One experimental MS therapeutic currently under development is a single amino acid mutant of a plant peptide termed kalata B1, of the cyclotide family. Like all cyclotides, the therapeutic candidate [T20K]kB1 is highly stable as it contains a cyclic backbone that is cross-linked by three disulfide bonds in a knot-like structure. This stability is much sought after for peptide drugs, which despite exquisite selectivity for their targets, are prone to rapid degradation in human serum. In preliminary investigations, it was found that [T20K]kB1 retains oral activity in experimental autoimmune encephalomyelitis, a model of MS in mice, thus opening up opportunities for oral dosing of the peptide. Although [T20K]kB1 can be synthetically produced, a recombinant production system provides advantages, specifically for reduced scale-up costs and reductions in chemical waste. In this study, we demonstrate the capacity of the Australian native Nicotiana benthamiana plant to produce a structurally identical [T20K]kB1 to that of the synthetic peptide. By optimizing the co-expressed cyclizing enzyme, precursor peptide arrangements, and transgene regulatory regions, we demonstrate a [T20K]kB1 yield in crude peptide extracts of ~ 0.3 mg/g dry mass) in whole plants and close to 1.0 mg/g dry mass in isolated infiltrated leaves. With large-scale plant production facilities coming on-line across the world, the sustainable and cost-effective production of cyclotide-based therapeutics is now within reach.
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Ciclotídeos , Esclerose Múltipla , Camundongos , Humanos , Animais , Ciclotídeos/genética , Ciclotídeos/química , Ciclotídeos/metabolismo , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/genética , Austrália , Nicotiana/genética , Nicotiana/metabolismo , Proteínas de Plantas/metabolismoRESUMO
Individuals with neurofibromatosis type 1 develop rat sarcoma virus (RAS)-mitogen-activated protein kinase-mitogen-activated and extracellular signal-regulated kinase (RAS-MAPK-MEK)-driven nerve tumors called neurofibromas. Although MEK inhibitors transiently reduce volumes of most plexiform neurofibromas in mouse models and in neurofibromatosis type 1 (NF1) patients, therapies that increase the efficacy of MEK inhibitors are needed. BI-3406 is a small molecule that prevents Son of Sevenless (SOS)1 interaction with Kirsten rat sarcoma viral oncoprotein (KRAS)-GDP, interfering with the RAS-MAPK cascade upstream of MEK. Single agent SOS1 inhibition had no significant effect in the DhhCre;Nf1 fl/fl mouse model of plexiform neurofibroma, but pharmacokinetics (PK)-driven combination of selumetinib with BI-3406 significantly improved tumor parameters. Tumor volumes and neurofibroma cell proliferation, reduced by MEK inhibition, were further reduced by the combination. Neurofibromas are rich in ionized calcium binding adaptor molecule 1 (Iba1)+ macrophages; combination treatment resulted in small and round macrophages, with altered cytokine expression indicative of altered activation. The significant effects of MEK inhibitor plus SOS1 inhibition in this preclinical study suggest potential clinical benefit of dual targeting of the RAS-MAPK pathway in neurofibromas. SIGNIFICANCE STATEMENT: Interfering with the RAS-mitogen-activated protein kinase (RAS-MAPK) cascade upstream of mitogen activated protein kinase kinase (MEK), together with MEK inhibition, augment effects of MEK inhibition on neurofibroma volume and tumor macrophages in a preclinical model system. This study emphasizes the critical role of the RAS-MAPK pathway in controlling tumor cell proliferation and the tumor microenvironment in benign neurofibromas.
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Neurofibroma Plexiforme , Neurofibroma , Neurofibromatose 1 , Animais , Camundongos , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Neurofibroma/tratamento farmacológico , Neurofibroma Plexiforme/tratamento farmacológico , Neurofibromatose 1/tratamento farmacológico , Neurofibromatose 1/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/uso terapêutico , Microambiente Tumoral , Proteína SOS1/metabolismoRESUMO
Introduction: Frailty is associated with adverse postoperative health outcomes, including increased mortality, longer length of stay, higher rehospitalization, and other complications. There are many frailty assessment tools are to assess the level of frailty in vascular surgery patients. The aim of this study was to perform a systematic review and meta-analysis to assess the association between the frailty levels described by different frailty scores and adverse postoperative health outcomes among hospitalized vascular surgery patients and patients undergoing amputation. Methods: Studies utilizing frailty scores and similar frailty assessment tools to describe frailty and investigate the association between frailty and health outcomes were searched. The primary outcomes of this study were in-hospital mortality, postdischarge mortality, length of hospital stay, rehospitalization, and discharge location. Additional outcomes included postoperative myocardial infarction, postoperative renal failure, cerebrovascular accident and stroke, comorbidities, and estimated glomerular filtration rate (eGFR) levels. Joanna Briggs Institute (JBI) Critical Appraisal Tools were used for quality assessment. Results: In total, 24 studies with 1,886,611 participants were included in the final analysis. The overall results found that higher in-hospital mortality and postdischarge mortality were significantly associated with frailty. Frailty was also found to be significantly associated with a longer length of hospital stay, higher rehospitalization, and higher likelihood of non-home discharge. In addition, the results also showed that frailty was significantly associated with all kinds of comorbidities investigated, except chronic kidney disease. However, lower eGFR levels were significantly associated with frailty. Conclusion: Among patients who underwent all types of vascular surgery and those who underwent amputations, assessment of frailty was significantly associated with adverse postoperative outcomes and multiple comorbidities. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=336374, identifier CRD42022336374.
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Acute exposure of cancer cells to high concentrations of type I interferon (IFN-I) drives growth arrest and apoptosis, whereas chronic exposure to low concentrations provides important prosurvival advantages. Tyrosine-phosphorylated IFN-stimulated gene (ISG) factor 3 (ISGF3) drives acute deleterious responses to IFN-I, whereas unphosphorylated (U-)ISGF3, lacking tyrosine phosphorylation, drives essential constitutive prosurvival mechanisms. Surprisingly, programmed cell death-ligand 1 (PD-L1), often expressed on the surfaces of tumor cells and well recognized for its importance in inactivating cytotoxic T cells, also has important cell-intrinsic protumor activities, including dampening acute responses to cytotoxic high levels of IFN-I and sustaining the expression of the low levels that benefit tumors. More thorough understanding of the newly recognized complex roles of IFN-I in cancer may lead to the identification of novel therapeutic strategies.
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Interferons , Neoplasias , Humanos , Interferons/metabolismo , Fator Gênico 3 Estimulado por Interferon/genética , Fator Gênico 3 Estimulado por Interferon/metabolismo , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Transdução de Sinais , Tirosina , Neoplasias/tratamento farmacológico , Neoplasias/genéticaRESUMO
Objective: Inhalation exposure systems are tools for delivering compounds (particles, vapors, and gases) under well-controlled conditions for toxicological testing. The objective of this project was to develop an automated computer-controlled system to expose small laboratory animals to precise concentrations of crude oil vapor (COV).Materials and Methods: Vapor from heated Deepwater Horizon surrogate oil was atomized into a fine mist then diluted with filtered air, then the air/droplet mixture was routed into an evaporation column with an high efficiency particulate air (HEPA) filter on its exit port. The HEPA filter was used to remove oil particles, thus ensuring only vapor would pass. The vapor was then introduced into a custom-built exposure chamber housing rats. A calibrated flame ionization detector was used to read the total volatile organic compounds (TVOC) in real time, and custom software was developed to automatically adjust the amount of oil entering the atomizer with a syringe pump. The software also controlled relative humidity and pressure inside the exposure chamber. Other exposure chamber environmental parameters, e.g. temperature and CO2 levels, were monitored. Four specific components within the COV were monitored during each exposure: benzene, toluene, ethylbenzene, and xylenes.Results: The TVOC vapor concentration control algorithm maintained median concentrations to within ±2 ppm of the target concentration (300 ppm) of TVOC during exposures lasting 6 h. The system could reach 90% of the desired target in less than 15 min, and repeat exposures were consistent and reproducible.Conclusion: This exposure system provided a highly automated tool for conducting COV inhalation toxicology studies.
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Petróleo , Compostos Orgânicos Voláteis , Ratos , Animais , Exposição por Inalação , Compostos Orgânicos Voláteis/toxicidade , Benzeno , Xilenos , Dióxido de Carbono , Gases , ToluenoRESUMO
INTRODUCTION: Covid-19 led to a sustained increase in deaths in all four United Kingdom nations, placing strain on the UK's palliative and end-of-life care sector and raising concerns about the long-term sustainability of the sector's funding and resourcing model in the face of rising demand for these services in the coming decades. SOURCES OF DATA: Published research, Marie Curie, King's College London Cicely Saunders Institute, Hull York Medical School, University of Hull, University of Cambridge, National Statistics, PubMed, DOI. AREAS OF AGREEMENT: Care for people at the end of their lives is a core part of the UK's health and care system with demand set to increase significantly as the UK's population ages. AREAS OF CONTROVERSY: The UK's funding model for palliative and end-of-life care, with most care delivered by charitable sector providers and reliant on charitable donations, may be unsustainable in the face of increasing demand. GROWING POINTS: The Covid-19 pandemic led to rapid service innovation in palliative and end-of-life care, and providers should assess which of and how these innovations can be retained after the pandemic. AREAS TIMELY FOR DEVELOPING RESEARCH: Although there has been a rapid growth in knowledge during Covid-19, gaps still remain including: the reasons underlying shifts to deaths at home and the implications for family carers; the education needs of the wider healthcare workforce in palliative care; the impact of specialist palliative care services on the wider health system, including hospital admissions and place of death; and inequalities in the experiences of dying, death and bereavement during Covid-19 among groups such as those from lower socioeconomic groups and BAME communities.
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COVID-19 , Assistência Terminal , COVID-19/epidemiologia , Humanos , Cuidados Paliativos , Pandemias , Reino Unido/epidemiologiaRESUMO
Workers involved in oil exploration and production in the upstream petroleum industry are exposed to crude oil vapor (COV). COV levels in the proximity of workers during production tank gauging and opening of thief hatches can exceed regulatory standards, and several deaths have occurred after opening thief hatches. There is a paucity of information regarding the effects of COV inhalation in the lung. To address these knowledge gaps, the present hazard identification study was undertaken to investigate the effects of an acute, single inhalation exposure (6 h) or a 28 d sub-chronic exposure (6 h/d × 4 d/wk × 4 wks) to COV (300 ppm; Macondo well surrogate oil) on ventilatory and non-ventilatory functions of the lung in a rat model 1 and 28 d after acute exposure, and 1, 28 and 90 d following sub-chronic exposure. Basal airway resistance was increased 90 d post-sub-chronic exposure, but reactivity to methacholine (MCh) was unaffected. In the isolated, perfused trachea preparation the inhibitory effect of the airway epithelium on reactivity to MCh was increased at 90 d post-exposure. Efferent cholinergic nerve activity regulating airway smooth muscle was unaffected by COV exposure. Acute exposure did not affect basal airway epithelial ion transport, but 28 d after sub-chronic exposure alterations in active (Na+ and Cl¯) and passive ion transport occurred. COV treatment did not affect lung vascular permeability. The findings indicate that acute and sub-chronic COV inhalation does not appreciably affect ventilatory properties of the rat, but transient changes in airway epithelium occur.
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Petróleo , Resistência das Vias Respiratórias , Animais , Exposição por Inalação/efeitos adversos , Pulmão , Cloreto de Metacolina/farmacologia , Petróleo/toxicidade , RatosRESUMO
Plant molecular farming aims to provide a green, flexible, and rapid alternative to conventional recombinant expression systems, capable of producing complex biologics such as enzymes, vaccines, and antibodies. Historically, the recombinant expression of therapeutic peptides in plants has proven difficult, largely due to their small size and instability. However, some plant species harbour the capacity for peptide backbone cyclization, a feature inherent in stable therapeutic peptides. One obstacle to realizing the potential of plant-based therapeutic peptide production is the proteolysis of the precursor before it is matured into its final stabilized form. Here we demonstrate the rational domestication of Nicotiana benthamiana within two generations to endow this plant molecular farming host with an expanded repertoire of peptide sequence space. The in planta production of molecules including an insecticidal peptide, a prostate cancer therapeutic lead, and an orally active analgesic is demonstrated.
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Produtos Biológicos , Domesticação , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Plantas/metabolismo , Peptídeos/metabolismo , Produtos Biológicos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
Workers in the oil and gas industry are at risk for exposure to a number of physical and chemical hazards at the workplace. Chemical hazard risks include inhalation of crude oil or its volatile components. While several studies have investigated the neurotoxic effects of volatile hydrocarbons, in general, there is a paucity of studies assessing the neurotoxicity of crude oil vapor (COV). Consequent to the 2010 Deepwater Horizon (DWH) oil spill, there is growing concern about the short- and long-term health effects of exposure to COV. NIOSH surveys suggested that the DWH oil spill cleanup workers experienced neurological symptoms, including depression and mood disorders, but the health effects apart from oil dispersants were difficult to discern. To investigate the potential neurological risks of COV, male Sprague-Dawley rats were exposed by whole-body inhalation to COV (300 ppm; Macondo surrogate crude oil) following an acute (6 h/d × 1 d) or sub-chronic (6 h/d × 4 d/wk. × 4 wks) exposure regimen. At 1, 28 or 90 d post-exposure, norepinephrine (NE), epinephrine (EPI), dopamine (DA) and serotonin (5-HT) were evaluated as neurotransmitter imbalances are associated with psychosocial-, motor- and cognitive- disorders. Sub-chronic COV exposure caused significant reductions in NE, EPI and DA in the dopaminergic brain regions, striatum (STR) and midbrain (MB), and a large increase in 5-HT in the STR. Further, sub-chronic exposure to COV caused upregulation of synaptic and Parkinson's disease-related proteins in the STR and MB. Whether such effects will lead to neurodegenerative outcomes remain to be investigated.
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Síndromes Neurotóxicas , Poluição por Petróleo , Petróleo , Poluentes Químicos da Água , Animais , Gases , Masculino , Síndromes Neurotóxicas/etiologia , Neurotransmissores , Ratos , Ratos Sprague-Dawley , Serotonina , Poluentes Químicos da Água/toxicidadeRESUMO
Glioblastoma (GBM) is the most prevalent malignant primary brain tumour in adults. GBM typically has a poor prognosis, mainly due to a lack of effective treatment options leading to tumour persistence or recurrence. We investigated the therapeutic potential of targeting anti-apoptotic BCL-2 proteins in GBM. Levels of anti-apoptotic BCL-xL and MCL-1 were consistently increased in GBM compared with non-malignant cells and tissue. Moreover, we found that relative to their differentiated counterparts, patient-derived GBM stem-like cells also displayed higher expression of anti-apoptotic BCL-2 family members. High anti-apoptotic BCL-xL and MCL-1 expression correlated with heightened susceptibility of GBM to BCL-2 family protein-targeting BH3-mimetics. This is indicative of increased apoptotic priming. Indeed, GBM displayed an obligate requirement for MCL-1 expression in both tumour development and maintenance. Investigating this apoptotic sensitivity, we found that sequential inhibition of BCL-xL and MCL-1 led to robust anti-tumour responses in vivo, in the absence of overt toxicity. These data demonstrate that BCL-xL and MCL-1 pro-survival function is a fundamental prerequisite for GBM survival that can be therapeutically exploited by BH3-mimetics.
Assuntos
Glioblastoma , Adulto , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína bcl-XRESUMO
Sunflower trypsin inhibitor-1 (SFTI-1) is a 14 amino acid cyclic peptide which has been effectively employed as a scaffold for engineering a range of peptide therapeutic candidates. Typically, synthesis of SFTI-1-based therapeutics is performed via solid-phase peptide synthesis and native chemical ligation, with significant financial and environmental costs associated. In planta synthesis of SFTI-1 based therapeutics serves as a greener approach for environmentally sustainable production. Here, we detail the methods for the transient expression, production, and purification of SFTI-1-based therapeutic peptides in Nicotiana benthamiana using a scalable and high-throughput approach. We demonstrate that a prerequisite for this is the co-expression of specialized asparaginyl endopeptidases (AEPs) that perform the backbone cyclization of SFTI-1. In our founding study, we were able to achieve in planta yields of a plasmin inhibitor SFTI-1 peptide at yields of ~60 µg/g of dried plant material.
Assuntos
Peptídeos Cíclicos/biossíntese , Ciclização , Peptídeos , Nicotiana/metabolismo , Tripsina/metabolismo , Inibidores da TripsinaRESUMO
PURPOSE: Low-dose whole lung radiation therapy (LDLR) has been proposed as a treatment for patients with acute respiratory distress syndrome associated with SARS-CoV-2 infection, and clinical trials are underway. There is an urgent need for preclinical evidence to justify this approach and inform dose, scheduling, and mechanisms of action. METHODS AND MATERIALS: Female C57BL/6 mice were treated with intranasal bleomycin sulfate (7.5 or 11.25 units/kg, day 0) and then exposed to whole lung radiation therapy (0.5, 1.0, or 1.5 Gy, or sham; day 3). Bodyweight was measured daily, and lung tissue was harvested for histology and flow cytometry on day 10. Computed tomography lung imaging was performed before radiation (day 3) and pre-endpoint (day 10). RESULTS: Bleomycin caused pneumonitis of variable severity, which correlated with weight loss. LDLR at 1.0 Gy was associated with a significant increase in the proportion of mice recovering to 98% of initial bodyweight, and a proportion of these mice exhibited less severe histopathologic lung changes. Mice experiencing moderate initial weight loss were more likely to respond to LDLR than those experiencing severe initial weight loss. In addition, LDLR (1.0 Gy) significantly reduced bleomycin-induced increases in interstitial macrophages, CD103+ dendritic cells (DCs), and neutrophil-DC hybrids. Overall, bleomycin-treated mice exhibited significantly higher percentages of nonaerated lung in left than right lungs, and LDLR (1.0 Gy) limited further reductions in aerated lung volume in right but not left lungs. LDLR at 0.5 and 1.5 Gy did not improve bodyweight, flow cytometric, or radiologic readouts of bleomycin-induced pneumonitis. CONCLUSIONS: Our data support the concept that LDLR can ameliorate acute inflammatory lung injury, identify 1.0 Gy as the most effective dose, and provide evidence that it is more effective in the context of moderate than severe pneumonitis. Mechanistically, LDLR at 1.0 Gy significantly suppressed bleomycin-induced accumulation of pulmonary interstitial macrophages, CD103+ DCs, and neutrophil-DC hybrids.