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1.
Proc Natl Acad Sci U S A ; 120(44): e2310770120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37883435

RESUMEN

The multifunctional adenovirus E1B-55K oncoprotein can induce cell transformation in conjunction with adenovirus E1A gene products. Previous data from transient expression studies and in vitro experiments suggest that these growth-promoting activities correlate with E1B-55K-mediated transcriptional repression of p53-targeted genes. Here, we analyzed genome-wide occupancies and transcriptional consequences of species C5 and A12 E1B-55Ks in transformed mammalian cells by combinatory ChIP and RNA-seq analyses. E1B-55K-mediated repression correlates with tethering of the viral oncoprotein to p53-dependent promoters via DNA-bound p53. Moreover, we found that E1B-55K also interacts with and represses transcription of numerous p53-independent genes through interactions with transcription factors that play central roles in cancer and stress signaling. Our results demonstrate that E1B-55K oncoproteins function as promiscuous transcriptional repressors of both p53-dependent and -independent genes and further support the model that manipulation of cellular transcription is central to adenovirus-induced cell transformation and oncogenesis.


Asunto(s)
Adenovirus Humanos , Proteínas Oncogénicas Virales , Animales , Humanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Adenovirus Humanos/genética , Adenovirus Humanos/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas E1B de Adenovirus/genética , Proteínas E1B de Adenovirus/metabolismo , Transformación Celular Neoplásica/genética , Adenoviridae/genética , Adenoviridae/metabolismo , Proteínas Oncogénicas Virales/metabolismo , ADN , Mamíferos/genética
2.
Exp Cell Res ; 442(2): 114258, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39293522

RESUMEN

Liver fibrosis, which is caused by viral infection, toxic exposure, and autoimmune diseases, is a chronic liver disease. Plasminogen activator inhibitor-1 (PAI-1) is a serine protease inhibitor of tissue-type plasminogen activator (tPA) and urokinase plasminogen activator, which convert plasminogen into plasmin. Therefore, PAI-1 suppresses fibrinolysis by blocking plasmin synthesis and is involved in liver fibrosis via extracellular matrix deposition. Small leucine zipper protein (sLZIP) acts as a transcription factor and plays critical roles in many cellular processes. However, the role of sLZIP in liver fibrosis remains unclear. In this study, we investigated the role of sLZIP in regulating PAI-1 transcription and liver fibrosis. sLZIP knockdown enhanced the expression of PAI-1 at the mRNA and protein levels. sLZIP knockdown also increased PAI-1 secretion and suppressed blood clot lysis by blocking tPA activity. Moreover, conditioned medium derived from sLZIP knockdown cells downregulated the expression of matrix metalloprotease (MMP)-2 and MMP-9 in the presence of tPA in hepatic stellate cells (HSCs). Liver-specific sLZIP knockout mice showed deteriorated liver fibrosis compared to control mice in a bile duct ligation-induced fibrosis model. These findings demonstrate that sLZIP functions as a negative regulator of liver fibrosis by suppressing PAI-1 transcription and HSC activation.


Asunto(s)
Cirrosis Hepática , Ratones Endogámicos C57BL , Ratones Noqueados , Inhibidor 1 de Activador Plasminogénico , Animales , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/genética , Ratones , Inhibidor 1 de Activador Plasminogénico/metabolismo , Inhibidor 1 de Activador Plasminogénico/genética , Humanos , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Masculino , Activador de Tejido Plasminógeno/metabolismo , Activador de Tejido Plasminógeno/genética
3.
Cancer Sci ; 115(8): 2839-2845, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38898727

RESUMEN

By taking advantage of forward genetic analysis in mice, we have demonstrated that Pak1 plays a crucial role during DMBA/TPA skin carcinogenesis. Although Pak1 has been considered to promote cancer development, its overall function remains poorly understood. To clarify the functional significance of Pak1 in detail, we sought to evaluate the possible effect of an allosteric inhibitor against PAK1 (NVS-PAK1-1) on a syngeneic mouse model. To this end, we established two cell lines, 9AS1 and 19AS1, derived from DMBA/TPA-induced squamous cell carcinoma (SCC) that engrafted in FVB mice. Based on our present results, NVS-PAK1-1 treatment significantly inhibited the growth of tumors derived from 9AS1 and 19AS1 cells in vitro and in vivo. RNA-sequencing analysis on the engrafted tumors indicates that NVS-PAK1-1 markedly potentiates the epidermal cell differentiation and enhances the immune response in the engrafted tumors. Consistent with these observations, we found an expansion of Pan-keratin-positive regions and potentially elevated infiltration of CD8-positive immune cells in NVS-PAK1-1-treated tumors as examined by immunohistochemical analyses. Together, our present findings strongly suggest that PAK1 is tightly linked to the development of SCC, and that its inhibition is a promising therapeutic strategy against SCC.


Asunto(s)
Carcinoma de Células Escamosas , Modelos Animales de Enfermedad , Neoplasias Cutáneas , Quinasas p21 Activadas , Animales , Quinasas p21 Activadas/metabolismo , Quinasas p21 Activadas/genética , Quinasas p21 Activadas/antagonistas & inhibidores , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/genética , Ratones , Línea Celular Tumoral , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Femenino , Diferenciación Celular/efectos de los fármacos , Acetato de Tetradecanoilforbol , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/metabolismo , Proliferación Celular/efectos de los fármacos
4.
Mol Carcinog ; 63(9): 1768-1782, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38869281

RESUMEN

To study mechanisms driving/inhibiting skin carcinogenesis, stage-specific expression of 14-3-3σ (Stratifin) was analyzed in skin carcinogenesis driven by activated rasHa/fos expression (HK1.ras/fos) and ablation of PTEN-mediated AKT regulation (K14.creP/Δ5PTENflx/flx). Consistent with 14-3-3σ roles in epidermal differentiation, HK1.ras hyperplasia and papillomas displayed elevated 14-3-3σ expression in supra-basal keratinocytes, paralleled by supra-basal p-MDM2166 activation and sporadic p-AKT473 expression. In bi-genic HK1.fos/Δ5PTENflx/flx hyperplasia, basal-layer 14-3-3σ expression appeared, and alongside p53/p21, was associated with keratinocyte differentiation and keratoacanthoma etiology. Tri-genic HK1.ras/fos-Δ5PTENflx/flx hyperplasia/papillomas initially displayed increased basal-layer 14-3-3σ, suggesting attempts to maintain supra-basal p-MDM2166 and protect basal-layer p53. However, HK1.ras/fos-Δ5PTENflx/flx papillomas exhibited increasing basal-layer p-MDM2166 activation that reduced p53, which coincided with malignant conversion. Despite p53 loss, 14-3-3σ expression persisted in well-differentiated squamous cell carcinomas (wdSCCs) and alongside elevated p21, limited malignant progression via inhibiting p-AKT1473 expression; until 14-3-3σ/p21 loss facilitated progression to aggressive SCC exhibiting uniform p-AKT1473. Analysis of TPA-promoted HK1.ras-Δ5PTENflx/flx mouse skin, demonstrated early loss of 14-3-3σ/p53/p21 in hyperplasia and papillomas, with increased p-MDM2166/p-AKT1473 that resulted in rapid malignant conversion and progression to poorly differentiated SCC. In 2D/3D cultures, membranous 14-3-3σ expression observed in normal HaCaT and SP1ras61 papilloma keratinocytes was unexpectedly detected in malignant T52ras61/v-fos SCC cells cultured in monolayers, but not invasive 3D-cells. Collectively, these data suggest 14-3-3σ/Stratifin exerts suppressive roles in papillomatogenesis via MDM2/p53-dependent mechanisms; while persistent p53-independent expression in early wdSCC may involve p21-mediated AKT1 inhibition to limit malignant progression.


Asunto(s)
Proteínas 14-3-3 , Proteínas Proto-Oncogénicas c-akt , Proteínas Proto-Oncogénicas c-mdm2 , Neoplasias Cutáneas , Proteína p53 Supresora de Tumor , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Ratones , Exorribonucleasas/metabolismo , Exorribonucleasas/genética , Carcinogénesis/metabolismo , Carcinogénesis/genética , Carcinogénesis/patología , Progresión de la Enfermedad , Humanos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Queratinocitos/metabolismo , Queratinocitos/patología , Regulación Neoplásica de la Expresión Génica
5.
Cell Commun Signal ; 22(1): 238, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654328

RESUMEN

Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the blood‒brain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.


Asunto(s)
Trampas Extracelulares , Accidente Cerebrovascular , Humanos , Trampas Extracelulares/metabolismo , Accidente Cerebrovascular/terapia , Animales , Barrera Hematoencefálica/metabolismo , Neutrófilos
6.
BMC Ophthalmol ; 24(1): 218, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773500

RESUMEN

PURPOSE: Comparing between the visual outcomes and post operative complications of two surgical treatments for sub macular hemorrhage, pars plana vitrectomy with tissue plasminogen activator (tPA) injection procedure, and pneumatic displacement of submacular hemorrhage with intravitreal tPA injection. METHODS: A retrospective chart review of patients with sub macular hemorrhage (SMH) was performed. Data was collected from 150 patients with sub macular hemorrhage. Patients were followed up from the day of admission and up to a year post surgery. Evaluation included visual acuity, optical coherence tomography (OCT), fundus examination and rates of complications. RESULTS: Pars plana vitrectomy procedure has showed a better visual outcome in small SMH. Comparing complications between the two treatment modalities, no significant difference has been found in the study. CONCLUSIONS: Pars plana vitrectomy and tPA showed a clear advantage with a trend of better visual acuity as well as a significant predictor to better visual acuity for small and medium sub macular hemorrhage.


Asunto(s)
Fibrinolíticos , Inyecciones Intravítreas , Hemorragia Retiniana , Activador de Tejido Plasminógeno , Tomografía de Coherencia Óptica , Agudeza Visual , Vitrectomía , Humanos , Activador de Tejido Plasminógeno/administración & dosificación , Vitrectomía/métodos , Hemorragia Retiniana/terapia , Hemorragia Retiniana/diagnóstico , Hemorragia Retiniana/tratamiento farmacológico , Estudios Retrospectivos , Masculino , Femenino , Anciano , Fibrinolíticos/administración & dosificación , Persona de Mediana Edad , Anciano de 80 o más Años
7.
BMC Public Health ; 24(1): 2208, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138572

RESUMEN

BACKGROUND: YouTube™ has a great role in providing information, which includes educational videos, to more than 2 billion users, making it the second most popular application in the world. BE-FAST is a modified version of the FAST mnemonic and is used to detect acute ischemic stroke by the patients or their relatives. The purpose of this study is to assess the overall usefulness of the information of YouTube in patients to realize an acute stroke attack. METHODS: YouTube was searched for the following five terms: "stroke", ''stroke diagnosis", "stroke signs", "brain attack" and "what is stroke" in November 2021 and May 2023, separately. Two independent neurology specialists scored each video by using Global Quality Scale (GQS). RESULTS: Among the total of 150 videos, the number that met inclusion criteria was 91 for the November 2021 search and 104 for the May 2023 search. For the 2021 search, in 30 videos (33%), the FAST mnemonic or its contents were noticed, whereas BE-FAST was mentioned in only four videos (4.4%). For the 2023 search, the FAST mnemonic or its contents were noticed in 36 videos (34.6%) and BE-FAST was mentioned in 11 videos (10.6%). Among the 2021 and 2023 searches, the mean GQS values were 3.09 and 2.96 points, 50 (54.8%) vs. 56 (53.8%) videos rated 3.5 points or higher (high quality), respectively. GQS scores of the videos mentioning balance, eyes, face, arms, speech, and time, the basic and advanced information about radiology and treatment, and mentioning FAST, BE-FAST, and TPA were significantly higher. CONCLUSION: We conclude that YouTube is not yet a very useful tool for patients to realize that they may have acute ischemic stroke, though over the years; information available on social media for healthcare information and education has improved.


Asunto(s)
Medios de Comunicación Sociales , Accidente Cerebrovascular , Grabación en Video , Humanos , Accidente Cerebrovascular/diagnóstico , Educación del Paciente como Asunto/métodos
8.
Ecotoxicol Environ Saf ; 281: 116635, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38944007

RESUMEN

Since we rely entirely on plastics or their products in our daily lives, plastics are the invention of the hour. Polyester plastics, such as Polyethylene Terephthalate (PET), are among the most often used types of plastics. PET plastics have a high ratio of aromatic components, which makes them very resistant to microbial attack and highly persistent. As a result, massive amounts of plastic trash accumulate in the environment, where they eventually transform into microplastic (<5 mm). Rather than macroplastics, microplastics are starting to pose a serious hazard to the environment. It is imperative that these polymer microplastics be broken down. Through the use of enrichment culture, the PET microplastic-degrading bacterium was isolated from solid waste management yards. Bacterial strain was identified as Gordonia sp. CN2K by 16 S rDNA sequence analysis and biochemical characterization. It is able to use polyethylene terephthalate as its only energy and carbon source. In 45 days, 40.43 % of the PET microplastic was degraded. By using mass spectral analysis and HPLC to characterize the metabolites produced during PET breakdown, the degradation of PET is verified. The metabolites identified in the spent medium included dimer compound, bis (2-hydroxyethyl) terephthalate (BHET), mono (2-hydroxyethyl) terephthalate (MHET), and terephthalate. Furthermore, the PET sheet exposed to the culture showed considerable surface alterations in the scanning electron microscope images. This illustrates how new the current work is.


Asunto(s)
Biodegradación Ambiental , Bacteria Gordonia , Tereftalatos Polietilenos , Tereftalatos Polietilenos/metabolismo , Tereftalatos Polietilenos/química , Bacteria Gordonia/metabolismo , Bacteria Gordonia/genética , Plásticos , Microplásticos , ARN Ribosómico 16S/genética
9.
Int J Mol Sci ; 25(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39201490

RESUMEN

Atherosclerosis is a chronic inflammatory disease that involves modified low-density lipoproteins (LDL) which play a pivotal role in the initiation and progression of the disease. Myeloperoxidase oxidized LDL (Mox-LDL) is considered to be the most patho-physiologically relevant type of modified LDL and has been reported to be ubiquitously present in atheroma plaques of patients with atherosclerosis. Besides its involvement in the latter disease state, Mox-LDL has also been shown to be implicated in the pathogenesis of various illnesses including sleep disorders, which are in turn associated with heart disease and depression in many intricate ways. Meanwhile, we have recently shown that lox-1-mediated Mox-LDL signaling modulates neuroserpin activity in endothelial cells, which could have major implications that go beyond the pathophysiology of stroke and cerebrovascular disease (CD). Of note is that tissue plasminogen activator (tPA), which is the main target of neuroserpin in the brain, has a crucial function in the processing of brain-derived neurotrophic factor (BDNF) into its mature form. This factor is known to be involved in major depressive disorder (MDD) development and pathogenesis. Since tPA is more conventionally recognized as being involved in fibrinolytic mechanisms, and its effect on the BDNF system in the context of MDD is still not extensively studied, we speculate that any Mox-LDL-driven change in the activity of tPA in patients with atherosclerosis may lead to a decrease in the production of mature BDNF, resulting in impaired neural plasticity and depression. Deciphering the mechanisms of interaction between those factors could help in better understanding the potentially overlapping pathological mechanisms that regulate disease processes in CD and MDD, supporting the possibility of novel and common therapeutic opportunities for millions of patients worldwide.


Asunto(s)
Aterosclerosis , Lipoproteínas LDL , Peroxidasa , Humanos , Aterosclerosis/metabolismo , Lipoproteínas LDL/metabolismo , Peroxidasa/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Depresión/metabolismo , Neuroserpina , Receptores Depuradores de Clase E/metabolismo , Trastorno Depresivo Mayor/metabolismo
10.
Molecules ; 29(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38731404

RESUMEN

This study explores the quantum size effects on the optical properties of pillar[n]arene (n = 5, 6, 7, 8) utilizing density functional theory (DFT) and wave function analysis. The mechanisms of electron transitions in one-photon absorption (OPA) and two-photon absorption (TPA) spectra are investigated, alongside the calculation of electron circular dichroism (ECD) for these systems. Transition Density Matrix (TDM) and electron-hole pair density maps are employed to study the electron excitation characteristics, unveiling a notable size dependency. Analysis of the transition electric dipole moment (TEDM) and the transition magnetic dipole moment (TMDM) reveals the electromagnetic interaction mechanism within pillar[n]arene. Raman spectra computations further elucidate vibrational modes, while interactions with external environments are studied using electrostatic potential (ESP) analysis, and electron delocalization is assessed under an external magnetic field, providing insights into the magnetically induced current phenomena within these supramolecular structures. The thermal stability of pillar[n]arene was investigated by ab initio molecular dynamics (AIMD).

11.
Molecules ; 29(19)2024 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-39407551

RESUMEN

The triply twisted Möbius carbon nanobelt (TMCNB) possesses an extremely distinctive geometric and electronic structure and therefore is anticipated to demonstrate outstanding optical properties. In this paper, through integrating quantum chemical calculations and wave function analysis approaches, in-depth studies are conducted on the one-photon absorption (OPA) and two-photon absorption (TPA) characteristics, aromaticity, and circular dichroism of the TMCNB. Inspired by this structure, we further deform it to construct a novel structure, MCNB2, and verify the stability of this structure, thereby confirming its rationality. Since variations in structure will result in dissimilar optical properties, we also undertake theoretical analyses on the absorption properties and circular dichroism of MCNB2. The outcomes of this study offer a significant theoretical foundation for the design and construction of chiral optoelectronic materials.

12.
Wilderness Environ Med ; 35(2): 183-197, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38577729

RESUMEN

The Wilderness Medical Society convened an expert panel to develop a set of evidence-based guidelines for the prevention and treatment of frostbite. We present a review of pertinent pathophysiology. We then discuss primary and secondary prevention measures and therapeutic management. Recommendations are made regarding each treatment and its role in management. These recommendations are graded on the basis of the quality of supporting evidence and balance between the benefits and risks or burdens for each modality according to methodology stipulated by the American College of Chest Physicians. This is an updated version of the guidelines published in 2019.


Asunto(s)
Congelación de Extremidades , Sociedades Médicas , Medicina Silvestre , Congelación de Extremidades/terapia , Congelación de Extremidades/prevención & control , Medicina Silvestre/normas , Medicina Silvestre/métodos , Humanos
13.
J Lipid Res ; 64(10): 100441, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37666362

RESUMEN

After feeding, adipose tissue lipoprotein lipase (LPL) activity should be maximized, therefore the potent LPL-inhibitory activity of angiopoietin-like protein 4 (ANGPTL4) must be blocked by ANGPTL8 through formation of ANGPTL4/8 complexes. ANGPTL4/8 tightly binds and protects LPL but also partially inhibits its activity. Recently, we demonstrated ANGPTL4/8 also binds tissue plasminogen activator (tPA) and plasminogen to generate plasmin that cleaves ANGPTL4/8 to restore LPL activity. Although fully active LPL in the fat postprandially is desirable, ANGPTL4/8 removal could subject LPL to profound inhibition by ANGPTL3/8 (the most potent circulating LPL inhibitor), inhibition by other LPL inhibitors like ANGPTL4, ANGPTL3, and ApoC3 or interfere with ApoC2-mediated LPL activation. To understand better these potential paradoxes, we examined LPL inhibition by ANGPTL3/8, ANGPTL4, ANGPTL3, and ApoC3 and LPL stimulation by ApoC2 in the presence of ANGPTL4/8 + tPA + plasminogen. Remarkably, ANGPTL3/8-mediated LPL inhibition was almost completely blocked, with the mechanism being cleavage of fibrinogen-like domain-containing ANGPTL3 present in the ANGPTL3/8 complex. The LPL-inhibitory effects of ANGPTL4, ANGPTL3, and ApoC3 were also largely reduced in the presence of ANGPTL4/8 + tPA + plasminogen. In contrast, the ability of ApoC2 to stimulate LPL activity was unaffected by ANGPTL4/8-mediated plasmin generation. Together, these results explain how plasmin generated by increased postprandial ANGPTL4/8 levels in adipose tissue enables maximal LPL activity by preventing ANGPTL3/8, ANGPTL4, ANGPTL3, and ApoC3 from inhibiting LPL, while permitting ApoC2-mediated LPL activation to occur.

14.
J Cell Biochem ; 124(7): 1040-1049, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37288821

RESUMEN

The acute ischemic stroke therapy of choice is the application of Alteplase, a drug containing the enzyme tissue-type plasminogen activator (tPa) which rapidly destabilizes blood clots. A central hallmark of stroke pathology is blood-brain barrier (BBB) breakdown associated with tight junction (TJ) protein degradation, which seems to be significantly more severe under therapeutic conditions. The exact mechanisms how tPa facilitates BBB breakdown are not entirely understood. There is evidence that an interaction with the lipoprotein receptor-related protein 1 (LRP1), allowing tPa transport across the BBB into the central nervous system, is necessary for this therapeutic side effect. Whether tPa-mediated disruption of BBB integrity is initiated directly on microvascular endothelial cells or other brain cell types is still elusive. In this study we could not observe any changes of barrier properties in microvascular endothelial cells after tPa incubation. However, we present evidence that tPa causes changes in microglial activation and BBB breakdown after LRP1-mediated transport across the BBB. Using a monoclonal antibody targeting the tPa binding sites of LRP1 decreased tPa transport across an endothelial barrier. Our results indicate that limiting tPa transport from the vascular system into the brain by coapplication of a LRP1-blocking monoclonal antibody might be a novel approach to minimize tPa-related BBB damage during acute stroke therapy.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Activador de Tejido Plasminógeno/efectos adversos , Activador de Tejido Plasminógeno/metabolismo , Células Endoteliales/metabolismo , Accidente Cerebrovascular Isquémico/inducido químicamente , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/patología , Anticuerpos Monoclonales/uso terapéutico , Lipoproteínas LDL
15.
Appl Environ Microbiol ; 89(1): e0160322, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36507653

RESUMEN

Polyethylene terephthalate (PET) is a prevalent synthetic polymer that is known to contaminate marine and terrestrial environments. Currently, only a limited number of PET-active microorganisms and enzymes (PETases) are known. This is in part linked to the lack of highly sensitive function-based screening assays for PET-active enzymes. Here, we report on the construction of a fluorescent biosensor based on Comamonas thiooxidans strain S23. C. thiooxidans S23 transports and metabolizes TPA, one of the main breakdown products of PET, using a specific tripartite tricarboxylate transporter (TTT) and various mono- and dioxygenases encoded in its genome in a conserved operon ranging from tphC-tphA1. TphR, an IclR-type transcriptional regulator is found upstream of the tphC-tphA1 cluster where TPA induces transcription of tphC-tphA1 up to 88-fold in exponentially growing cells. In the present study, we show that the C. thiooxidans S23 wild-type strain, carrying the sfGFP gene fused to the tphC promoter, senses TPA at concentrations as low as 10 µM. Moreover, a deletion mutant lacking the catabolic genes involved in TPA degradation thphA2-A1 (ΔtphA2A3BA1) is up to 10,000-fold more sensitive and detects TPA concentrations in the nanomolar range. This is, to our knowledge, the most sensitive reporter strain for TPA and we demonstrate that it can be used for the detection of enzymatic PET breakdown products. IMPORTANCE Plastics and microplastics accumulate in all ecological niches. The construction of more sensitive biosensors allows to monitor and screen potential PET degradation in natural environments and industrial samples. These strains will also be a valuable tool for functional screenings of novel PETase candidates and variants or monitoring of PET recycling processes using biocatalysts. Thereby they help us to enrich the known biodiversity and efficiency of PET degrading organisms and enzymes and understand their contribution to environmental plastic degradation.


Asunto(s)
Técnicas Biosensibles , Comamonas , Monitoreo del Ambiente , Plásticos , Tereftalatos Polietilenos , Comamonas/enzimología , Comamonas/genética , Ecosistema , Hidrolasas/genética , Hidrolasas/metabolismo , Plásticos/metabolismo , Tereftalatos Polietilenos/metabolismo , Técnicas Biosensibles/métodos , Monitoreo del Ambiente/métodos , Microplásticos/metabolismo
16.
FASEB J ; 36(10): e22564, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36165219

RESUMEN

The outcome of ischemic stroke can be improved by further refinements of thrombolysis and reperfusion strategies. Factor VII activating protease (FSAP) is a circulating serine protease that could be important in this context. Its levels are raised in patients as well as mice after stroke and a single nucleotide polymorphism (SNP) in the coding sequence, which results in an inactive enzyme, is linked to an increased risk of stroke. In vitro, FSAP cleaves fibrinogen to promote fibrinolysis, activates protease-activated receptors, and decreases the cellular cytotoxicity of histones. Based on these facts, we hypothesized that FSAP can be used as a treatment for ischemic stroke. A combination of tissue plasminogen activator (tPA), a thrombolytic drug, and recombinant serine protease domain of FSAP (FSAP-SPD) improved regional cerebral perfusion and neurological outcome and reduced infarct size in a mouse model of thromboembolic stroke. FSAP-SPD also improved stroke outcomes and diminished the negative consequences of co-treatment with tPA in the transient middle cerebral artery occlusion model of stroke without altering cerebral perfusion. The inactive MI-isoform of FSAP had no impact in either model. FSAP enhanced the lysis of blood clots in vitro, but in the tail transection model of hemostasis, FSAP-SPD treatment provoked a faster clotting time indicating that it also has pro-coagulant actions. Thus, apart from enhancing thrombolysis, FSAP has multiple effects on stroke progression and represents a promising novel therapeutic strategy in the treatment of ischemic stroke.


Asunto(s)
Coagulantes , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Animales , Modelos Animales de Enfermedad , Factor VII , Fibrinógeno , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Histonas , Ratones , Péptido Hidrolasas , Receptores Proteinasa-Activados , Serina Endopeptidasas/genética , Accidente Cerebrovascular/tratamiento farmacológico , Activador de Tejido Plasminógeno/genética
17.
Mol Pharm ; 20(7): 3505-3518, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37283406

RESUMEN

Madin-Darby canine kidney (MDCK) cells are widely used to study epithelial cell functionality. Their low endogenous drug transporter protein levels make them an amenable system to investigate transepithelial permeation and drug transporter protein activity after their transfection. MDCK cells display diverse phenotypic traits, and as such, laboratory-to-laboratory variability in drug permeability assessments is observed. Consequently, in vitro-in vivo extrapolation (IVIVE) approaches using permeability and/or transporter activity data require calibration. A comprehensive proteomic quantification of 11 filter-grown parental or mock-transfected MDCK monolayers from 8 different pharmaceutical laboratories using the total protein approach (TPA) is provided. The TPA enables estimations of key morphometric parameters such as monolayer cellularity and volume. Overall, metabolic liability to xenobiotics is likely to be limited for MDCK cells due to the low expression of required enzymes. SLC16A1 (MCT1) was the highest abundant SLC transporter linked to xenobiotic activity, while ABCC4 (MRP4) was the highest abundant ABC transporter. Our data supports existing findings that claudin-2 levels may be linked to tight junction modulation, thus impacting trans-epithelial resistance. This unique database provides data on more than 8000 protein copy numbers and concentrations, thus allowing an in-depth appraisal of the control monolayers used in each laboratory.


Asunto(s)
Proteoma , Proteómica , Animales , Perros , Células de Riñón Canino Madin Darby , Proteoma/metabolismo , Uniones Estrechas/metabolismo , Riñón/metabolismo , Proteínas Portadoras/metabolismo
18.
Am J Emerg Med ; 67: 196.e1-196.e2, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36948989

RESUMEN

Tissue plasminogen activator (tPA) is a cornerstone treatment for acute ischemic stroke (AIS). Administration of tPA is not without risk, and can provoke life threatening adverse reactions. Retropharyngeal hematoma (RPH) following tPA administration has only been reported after tenecteplase (TNK) administration for ST elevation myocardial infarction (STEMI). A 78 year old patient received tPA for AIS. Following administration of tPA, this patient developed acute signs and symptoms of what appeared to be a more well-known adverse reaction of tPA administration - angioedema. After CT and laboratory findings, our patient received cryoprecipitate for tPA reversal. Our case highlights a unique case of RPH mimicking angioedema following tPA administration.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Anciano , Activador de Tejido Plasminógeno/efectos adversos , Fibrinolíticos/efectos adversos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/inducido químicamente , Terapia Trombolítica/efectos adversos , Resultado del Tratamiento , Isquemia Encefálica/tratamiento farmacológico
19.
Ecotoxicol Environ Saf ; 262: 115116, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37315364

RESUMEN

During the 20th century, thousands of tons of munitions containing organoarsenic chemical warfare agents (CWAs) were dumped into oceans, seas and inland waters around the world. As a result, organoarsenic CWAs continue to leak from corroding munitions into sediments and their environmental concentrations are expected to peak over the next few decades. There remains, however, a lack of knowledge about their potential toxicity to aquatic vertebrates, such as fish. The aim of this study was to fill in this gap in research, by investigating the acute toxicity of organoarsenic CWAs on fish embryos, using the model species, Danio rerio. To estimate the acute toxicity thresholds of organoarsenic CWAs (Clark I, Adamsite, PDCA), a CWA-related compound (TPA), as well as four organoarsenic CWA degradation products (Clark I[ox], Adamsite[ox], PDCA[ox], TPA[ox]), standardized tests were performed following the OECD no. 236 Fish Embryo Acute Toxicity Test guidelines. Additionally, the detoxification response in D. rerio embryos was investigated by analysing the mRNA expression of five genes encoding antioxidant enzymes (CAT, SOD, GPx, GR and GST). During the 96 h of exposure, organoarsenic CWAs induced lethal effects in D. rerio embryos at very low concentrations (classified as 1st category pollutants according to GHS categorization), and were therefore deemed to be serious environmental hazards. Although TPA and the four CWA degradation products caused no acute toxicity even at their maximum solubility, the transcription of antioxidant-related genes was altered upon exposure to these compounds, indicating the need for further testing for chronic toxicity. Incorporating the results of this study into ecological risk assessments will provide a more accurate prediction of the environmental hazards posed by CWA-related organoarsenicals.

20.
J Stroke Cerebrovasc Dis ; 32(12): 107394, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37866294

RESUMEN

BACKGROUND: Each year, stroke-related death and disability claim over 143 million years of healthy life globally. Despite accounting for much of the global stroke burden, acute stroke care in Low-and-Middle-Income Countries remains suboptimal. Thrombolysis, an effective treatment option for stroke, is only received by a minority of stroke patients in these settings. AIM: To determine the context-specific barriers and facilitators for the implementation of mainstream stroke thrombolysis in a Ghanaian hospital. METHODS: We employed a mixed-methods approach involving key stakeholders (recipients, providers, and leaders) in the acute stroke care continuum. Surveys were administered to acute stroke patients, and in-depth key informant interviews were conducted with experts in stroke care, including a neurologist, medical director, neurology residents, a stroke nurse, emergency physicians, a radiologist, and a pharmacist. The data collected from these interviews were transcribed and analysed using content analysis with the CFIR (Consolidated Framework for Implementation Research) model as a guiding template. Two independent coders were involved in the analysis process to ensure reliability and accuracy. RESULTS: The stroke thrombolysis rate over a 6-month period was 0.83% (2 out of 242), with an average door-to-needle time among thrombolyzed patients being 2 hours, 37 minutes. Only 12.8% of patients (31 out of 242) presented within 4.5 hours of stroke symptom onset. The most significant obstacle to the implementation of acute stroke thrombolysis was related to the characteristics of the individuals involved, notably delays in presenting to the hospital among stroke patients due to a lack of knowledge about stroke symptoms and cultural beliefs. Additionally, a significant bottleneck that contributed to the discrepancy between the number of patients who presented within the 4.5-6 hour window and the number of patients who actually received thrombolysis was the inability to pay for the cost of thrombolytic agents. This was followed by challenges in the implementation processes. CONCLUSIONS: Addressing challenges related to stroke awareness, and financial constraints via multi-level stakeholder engagement, and enactment of stroke protocols are crucial steps in ensuring a successful implementation of a stroke thrombolysis program in a resource-limited setting.


Asunto(s)
Accidente Cerebrovascular , Terapia Trombolítica , Humanos , Ghana , Reproducibilidad de los Resultados , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Fibrinolíticos/efectos adversos , Hospitales
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