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1.
Nat Commun ; 15(1): 6565, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39095373

RESUMEN

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.


Asunto(s)
Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Clitoria/metabolismo , Clitoria/genética , Ciclotidas/genética , Ciclotidas/química , Ciclotidas/metabolismo , Fijación del Nitrógeno/genética , Evolución Molecular , Ciclización , Filogenia , Familia de Multigenes , Duplicación de Gen , Fabaceae/genética , Fabaceae/metabolismo , Albúminas/metabolismo , Albúminas/genética , Genoma de Planta , Cisteína Endopeptidasas
2.
Phlebology ; : 2683555241260926, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046331

RESUMEN

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.

3.
J Toxicol Environ Health A ; 87(13): 541-559, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38682597

RESUMEN

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.


Asunto(s)
Estrés Oxidativo , Cemento de Policarboxilato , Impresión Tridimensional , Ratas Sprague-Dawley , Animales , Masculino , Ratas , Estrés Oxidativo/efectos de los fármacos , Biomarcadores/metabolismo , Compuestos de Bencidrilo/toxicidad , Fenoles/toxicidad , Miocardio/metabolismo , Contaminantes Atmosféricos/toxicidad , Corazón/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo III/metabolismo
4.
Life Sci Alliance ; 7(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38458648

RESUMEN

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.


Asunto(s)
Citofagocitosis , Neurofibroma Plexiforme , Humanos , Macrófagos/patología , Quinasas de Proteína Quinasa Activadas por Mitógenos , Neurofibroma Plexiforme/patología , Transducción de Señal , Microambiente Tumoral
5.
Int J Radiat Oncol Biol Phys ; 120(1): 162-177, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38493899

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Ftalazinas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Fármacos Sensibilizantes a Radiaciones , Glioblastoma/radioterapia , Glioblastoma/patología , Humanos , Fármacos Sensibilizantes a Radiaciones/farmacología , Línea Celular Tumoral , Ftalazinas/farmacología , Ftalazinas/uso terapéutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Indoles/farmacología , Piperazinas/farmacología , Piperazinas/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Reproducibilidad de los Resultados , Técnicas de Cultivo Tridimensional de Células/métodos
6.
Int J Radiat Oncol Biol Phys ; 118(5): 1371-1378, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38211641

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Piperazinas , Humanos , Masculino , Anciano , Femenino , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Ftalazinas/efectos adversos
7.
Neuro Oncol ; 26(4): 625-639, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-37936324

RESUMEN

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.


Asunto(s)
Glioblastoma , Humanos , Glioblastoma/patología , Integrinas/metabolismo , Línea Celular Tumoral , Citoesqueleto/metabolismo , Citoesqueleto/patología , Invasividad Neoplásica , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo
8.
Eur J Immunol ; 53(11): e2350559, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37490492

RESUMEN

Cytokine production by memory T cells is a key mechanism of T cell mediated protection. However, we have limited understanding of the persistence of cytokine producing T cells during memory cell maintenance and secondary responses. We interrogated antigen-specific CD4 T cells using a mouse influenza A virus infection model. Although CD4 T cells detected using MHCII tetramers declined in lymphoid and non-lymphoid organs, we found similar numbers of cytokine+ CD4 T cells at days 9 and 30 in the lymphoid organs. CD4 T cells with the capacity to produce cytokines expressed higher levels of pro-survival molecules, CD127 and Bcl2, than non-cytokine+ cells. Transcriptomic analysis revealed a heterogeneous population of memory CD4 T cells with three clusters of cytokine+ cells. These clusters match flow cytometry data and reveal an enhanced survival signature in cells capable of producing multiple cytokines. Following re-infection, multifunctional T cells expressed low levels of the proliferation marker, Ki67, whereas cells that only produce the anti-viral cytokine, interferon-γ, were more likely to be Ki67+ . Despite this, multifunctional memory T cells formed a substantial fraction of the secondary memory pool. Together these data indicate that survival rather than proliferation may dictate which populations persist within the memory pool.


Asunto(s)
Linfocitos T CD4-Positivos , Virus de la Influenza A , Linfocitos T CD4-Positivos/metabolismo , Antígeno Ki-67 , Citocinas/metabolismo , Interferón gamma/metabolismo , Memoria Inmunológica
9.
J Toxicol Environ Health A ; 86(16): 575-596, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37350301

RESUMEN

Three-dimensional (3D) printing of manufactured goods has increased in the last 10 years. The increased use of this technology has resulted in questions regarding the influence of inhaling emissions generated during printing. The goal of this study was to determine if inhalation of particulate and/or toxic chemicals generated during printing with polycarbonate (PC) plastic affected the neuroendocrine system. Male rats were exposed to 3D-printer emissions (592 µg particulate/m3 air) or filtered air for 4 h/day (d), 4 days/week and total exposures lengths were 1, 4, 8, 15 or 30 days. The effects of these exposures on hormone concentrations, and markers of function and/or injury in the olfactory bulb, hypothalamus and testes were measured after 1, 8 and 30 days exposure. Thirty days of exposure to 3D printer emissions resulted in reductions in thyroid stimulating hormone, follicle stimulating hormone and prolactin. These changes were accompanied by (1) elevation in markers of cell injury; (2) reductions in active mitochondria in the olfactory bulb, diminished gonadotropin releasing hormone cells and fibers as well as less tyrosine hydroxylase immunolabeled fibers in the arcuate nucleus; and (3) decrease in spermatogonium. Polycarbonate plastics may contain bisphenol A, and the effects of exposure to these 3D printer-generated emissions on neuroendocrine function are similar to those noted following exposure to bisphenol A.


Asunto(s)
Compuestos de Bencidrilo , Plásticos , Ratas , Masculino , Animales , Impresión Tridimensional
10.
Mol Cancer Res ; 21(9): 975-990, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37310811

RESUMEN

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.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Receptores de Oncostatina M , Transducción de Señal , Oncostatina M/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Transición Epitelial-Mesenquimal , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Microambiente Tumoral
11.
Appl Microbiol Biotechnol ; 107(15): 4815-4831, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37358812

RESUMEN

Beauveria bassiana is a cosmopolitan entomopathogenic fungus that can infect over 1000 insect species. During growth inside the host, B. bassiana transitions from hyphal to yeast-like unicellular growth as blastospores. Blastospores are well suited as an active ingredient in biopesticides due to their ease of production by liquid fermentation. Herein, we investigated the impact of hyperosmotic growth environments mediated by ionic and non-ionic osmolytes on two strains of B. bassiana (ESALQ1432 and GHA) relevant to growth morphology, blastospore production, desiccation tolerance, and insecticidal activity. Polyethylene glycol (PEG200) increased osmotic pressure in submerged cultures leading to decreased blastospore size but higher blastospore yields for one strain. Morphologically, decreased blastospore size was linked to increased osmotic pressure. However, smaller blastospores from PEG200 supplemented cultures after air-drying exhibited delayed germination. Ionic osmolytes (NaCl and KCl) generated the same osmotic pressure (2.5-2.7 MPa) as 20% glucose and boosted blastospore yields (> 2.0 × 109 blastospores mL-1). Fermentation performed in a bench-scale bioreactor consistently promoted high blastospore yields when using NaCl (2.5 MPa) amended media within 3 days. Mealworm larvae (Tenebrio molitor) were similarly susceptible to NaCl-grown blastospores and aerial conidia in a dose-time-dependent manner. Collectively, these results demonstrate the use of hyperosmotic liquid culture media in triggering enhanced yeast-like growth by B. bassiana. Understanding the role of osmotic pressure on blastospore formation and fitness will hasten the development of viable commercial fungal biopesticides. KEY POINTS: • Osmotic pressure plays a critical role in submerged fermentation of B. bassiana. • Ionic/non-ionic osmolytes greatly impact blastospore morphology, fitness, and yield. • Desiccation tolerance and bioefficacy of blastospores are affected by the osmolyte.


Asunto(s)
Beauveria , Animales , Agentes de Control Biológico , Presión Osmótica , Cloruro de Sodio , Esporas Fúngicas
12.
J Nat Prod ; 86(5): 1222-1229, 2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37099442

RESUMEN

Cyclotides are a unique family of stable and cyclic mini-proteins found in plants that have nematicidal and anthelmintic activities. They are distributed across the Rubiaceae, Violaceae, Fabaceae, Cucurbitaceae, and Solanaceae plant families, where they are posited to act as protective agents against pests. In this study, we tested the nematicidal properties of extracts from four major cyclotide-producing plants, Oldenlandia affinis, Clitoria ternatea, Viola odorata, and Hybanthus enneaspermus, against the free-living model nematode Caenorhabditis elegans. We evaluated the nematicidal activity of the cyclotides kalata B1, cycloviolacin O2, and hyen D present in these extracts and found them to be active against the larvae of C. elegans. Both the plant extracts and isolated cyclotides exerted dose-dependent toxicity on the first-stage larvae of C. elegans. Isolated cyclotides caused death or damage upon interacting with the worms' mouth, pharynx, and midgut or membrane. Cycloviolacin O2 and hyen D produced bubble-like structures around the C. elegans membrane, termed blebs, implicating membrane disruption causing toxicity and death. All tested cyclotides lost their toxicity when the hydrophobic patches present on them were disrupted via a single-point mutation. The present results provide a facile assay design to measure and explore the nematicidal activities of plant extracts and purified cyclotides on C. elegans.


Asunto(s)
Ciclotidas , Fabaceae , Nematodos , Violaceae , Animales , Antinematodos/farmacología , Caenorhabditis elegans , Ciclotidas/farmacología , Ciclotidas/química , Fabaceae/química , Extractos Vegetales/química , Proteínas de Plantas/química
13.
Transgenic Res ; 32(1-2): 121-133, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36930229

RESUMEN

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.


Asunto(s)
Ciclotidas , Esclerosis Múltiple , Ratones , Humanos , Animales , Ciclotidas/genética , Ciclotidas/química , Ciclotidas/metabolismo , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/genética , Australia , Nicotiana/genética , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo
14.
Front Cardiovasc Med ; 10: 1065779, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36798484

RESUMEN

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.

15.
J Pharmacol Exp Ther ; 385(2): 106-116, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36849412

RESUMEN

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.


Asunto(s)
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatosis 1 , Animales , Ratones , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos , Neurofibroma/tratamiento farmacológico , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Neurofibromatosis 1/patología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/uso terapéutico , Microambiente Tumoral , Proteína SOS1/metabolismo
16.
Trends Cancer ; 9(1): 83-92, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36216730

RESUMEN

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.


Asunto(s)
Interferones , Neoplasias , Humanos , Interferones/metabolismo , Factor 3 de Genes Estimulados por el Interferón/genética , Factor 3 de Genes Estimulados por el Interferón/metabolismo , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/genética , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Transducción de Señal , Tirosina , Neoplasias/tratamiento farmacológico , Neoplasias/genética
17.
J Peripher Nerv Syst ; 28(1): 32-40, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36573790

RESUMEN

Recent work identified anti-GM2 and anti-GalNAc-GD1a IgG ganglioside antibodies as biomarkers in dogs clinically diagnosed with acute canine polyradiculoneuritis, in turn considered a canine equivalent of Guillain-Barré syndrome. This study aims to investigate the serum prevalence of similar antibodies in cats clinically diagnosed with immune-mediated polyneuropathies. The sera from 41 cats clinically diagnosed with immune-mediated polyneuropathies (IPN), 9 cats with other neurological or neuromuscular disorders (ONM) and 46 neurologically normal cats (CTRL) were examined for the presence of IgG antibodies against glycolipids GM1, GM2, GD1a, GD1b, GalNAc-GD1a, GA1, SGPG, LM1, galactocerebroside and sulphatide. A total of 29/41 IPN-cats had either anti-GM2 or anti-GalNAc-GD1a IgG antibodies, with 24/29 cats having both. Direct comparison of anti-GM2 (sensitivity: 70.7%; specificity: 78.2%) and anti-GalNAc-GD1a (sensitivity: 70.7%; specificity: 70.9%) antibodies narrowly showed anti-GM2 IgG antibodies to be the better marker for identifying IPN-cats when compared to the combined ONM and CTRL groups (P = .049). Anti-GA1 and/or anti-sulphatide IgG antibodies were ubiquitously present across all sample groups, whereas antibodies against GM1, GD1a, GD1b, SGPG, LM1 and galactocerebroside were overall only rarely observed. Anti-GM2 and anti-GalNAc-GD1a IgG antibodies may serve as serum biomarkers for immune-mediated polyneuropathies in cats, as previously observed in dogs and humans.


Asunto(s)
Síndrome de Guillain-Barré , Polineuropatías , Humanos , Gatos , Animales , Perros , Galactosilceramidas , Gangliósido G(M1) , Gangliósidos , Inmunoglobulina G , Polineuropatías/diagnóstico , Polineuropatías/veterinaria , Biomarcadores , Autoanticuerpos , Gangliósido G(M2)
18.
Inhal Toxicol ; 34(11-12): 340-349, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36007004

RESUMEN

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.


Asunto(s)
Petróleo , Compuestos Orgánicos Volátiles , Ratas , Animales , Exposición por Inhalación , Compuestos Orgánicos Volátiles/toxicidad , Benceno , Xilenos , Dióxido de Carbono , Gases , Tolueno
19.
Toxicol Appl Pharmacol ; 450: 116154, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35798068

RESUMEN

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.


Asunto(s)
Petróleo , Resistencia de las Vías Respiratorias , Animales , Exposición por Inhalación/efectos adversos , Pulmón , Cloruro de Metacolina/farmacología , Petróleo/toxicidad , Ratas
20.
Br Med Bull ; 142(1): 44-51, 2022 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-35792900

RESUMEN

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.


Asunto(s)
COVID-19 , Cuidado Terminal , COVID-19/epidemiología , Humanos , Cuidados Paliativos , Pandemias , Reino Unido/epidemiología
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