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1.
J Med Virol ; 96(8): e29840, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39092805

RESUMO

Kaposi sarcoma (KS) is a neoplasm of vascular origin that promotes angiogenesis and the growth of endothelial cells triggered by the Kaposi Sarcoma-associated Herpes Virus (KSHV). When associated with HIV, KSHV becomes more aggressive and rapidly evolves. The HIV-1 TAT protein can be essential in developing AIDS-associated KS by promoting angiogenesis and increasing KSHV replication. Therefore, we evaluated the genetic profile of the first exon of tat gene among groups of people living with HIV (PLHIV) with (case group, n = 36) or without KS, this later with (positive control group, n = 46) and without KSHV infection (negative control group, n = 24); all individuals under antiretroviral therapy. The genetic diversity, the DN/DS ratio, and the genetic entropy of the first exon of tat were higher in the case group, followed by the positive control group, which was higher than the negative control group. The number of tat codons under positive selection was seven in the case group, six in the positive control group, and one in the negative control group. The prevalence of HIV viral loads below the detection limit was equal in the case and positive control groups, which were lower than in the negative control group. The mean CD4+ T cell counts were higher in the negative control group, followed by the positive control group, and followed by the case group. These results emphasize the negative influence of KSHV in antiretroviral treatment, as well as the HIV-specific TAT profile among PLHIV who developed KS.


Assuntos
Coinfecção , Infecções por HIV , Herpesvirus Humano 8 , Sarcoma de Kaposi , Produtos do Gene tat do Vírus da Imunodeficiência Humana , Humanos , Sarcoma de Kaposi/virologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Masculino , Herpesvirus Humano 8/genética , Feminino , Adulto , Pessoa de Meia-Idade , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Coinfecção/virologia , Coinfecção/tratamento farmacológico , HIV-1/genética , HIV-1/efeitos dos fármacos , Variação Genética , Carga Viral , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4
2.
J Neurogenet ; : 1-10, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913811

RESUMO

The neurogenetics and vision community recently mourned William L. Pak, PhD, whose pioneering work spearheaded the genetic, electrophysiological, and molecular bases of biological processes underpinning vision. This essay provides a historical background to the daunting challenges and personal experiences that carved the path to seminal findings. It also reflects on the intellectual framework, mentoring philosophy, and inspirational legacy of Bill Pak's research. An emphasis and perspectives are placed on the discoveries and implications to date of the phosphatidylinositol-specific phospholipase C (PI-PLC), NorpA, and the cyclophilin, NinaA of the fruit fly, Drosophila melanogaster, and their respective mammalian homologues, PI-PLCß4, and cyclophilin-related protein, Ran-binding protein 2 (Ranbp2) in critical biological processes and diseases of photoreceptors and other neurons.

3.
ACS Chem Neurosci ; 15(10): 1967-1989, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38657106

RESUMO

Disturbances in protein phase transitions promote protein aggregation─a neurodegeneration hallmark. The modular Ran-binding protein 2 (Ranbp2) is a cytosolic molecular hub for rate-limiting steps of phase transitions of Ran-GTP-bound protein ensembles exiting nuclear pores. Chaperones also regulate phase transitions and proteostasis by suppressing protein aggregation. Ranbp2 haploinsufficiency promotes the age-dependent neuroprotection of the chorioretina against phototoxicity by proteostatic regulations of neuroprotective substrates of Ranbp2 and by suppressing the buildup of polyubiquitylated substrates. Losses of peptidyl-prolyl cis-trans isomerase (PPIase) and chaperone activities of the cyclophilin domain (CY) of Ranbp2 recapitulate molecular effects of Ranbp2 haploinsufficiency. These CY impairments also stimulate deubiquitylation activities and phase transitions of 19S cap subunits of the 26S proteasome that associates with Ranbp2. However, links between CY moonlighting activity, substrate ubiquitylation, and proteostasis remain incomplete. Here, we reveal the Ranbp2 regulation of small heat shock chaperones─crystallins in the chorioretina by proteomics of mice with total or selective modular deficits of Ranbp2. Specifically, loss of CY PPIase of Ranbp2 upregulates αA-Crystallin, which is repressed in adult nonlenticular tissues. Conversely, impairment of CY's chaperone activity opposite to the PPIase pocket downregulates a subset of αA-Crystallin's substrates, γ-crystallins. These CY-dependent effects cause age-dependent and chorioretinal-selective declines of ubiquitylated substrates without affecting the chorioretinal morphology. A model emerges whereby inhibition of Ranbp2's CY PPIase remodels crystallins' expressions, subdues molecular aging, and preordains the chorioretina to neuroprotection by augmenting the chaperone capacity and the degradation of polyubiquitylated substrates against proteostatic impairments. Further, the druggable Ranbp2 CY holds pan-therapeutic potential against proteotoxicity and neurodegeneration.


Assuntos
Ciclofilinas , Chaperonas Moleculares , Complexo de Proteínas Formadoras de Poros Nucleares , Peptidilprolil Isomerase , Proteostase , Animais , Chaperonas Moleculares/metabolismo , Camundongos , Ciclofilinas/metabolismo , Proteostase/fisiologia , Peptidilprolil Isomerase/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Cristalinas/metabolismo
4.
BMC Nurs ; 23(1): 96, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321491

RESUMO

BACKGROUND: Nurses play an important role in interprofessional pharmaceutical care. Curricula related to pharmaceutical care, however, vary a lot. Mapping the presence of pharmaceutical care related domains and competences in nurse educational programs can lead to a better understanding of the extent to which curricula fit expectations of the labour market. The aim of this study was to describe 1) the presence of pharmaceutical care oriented content in nursing curricula at different educational levels and 2) nursing students' perceived readiness to provide nurse pharmaceutical care in practice. METHODS: A quantitative cross-sectional survey design was used. Nursing schools in 14 European countries offering educational programs for levels 4-7 students were approached between January and April 2021. Through an online survey final year students had to indicate to what extent pharmaceutical care topics were present in their curriculum. RESULTS: A total of 1807 students participated, of whom 8% had level 4-5, 80% level 6, 12% level 7. Up to 84% of the students indicated that pharmaceutical care content was insufficiently addressed in their curriculum. On average 14% [range 0-30] felt sufficiently prepared to achieve the required pharmaceutical care competences in practice. In level 5 curricula more pharmaceutical care domains were absent compared with other levels. CONCLUSIONS: Although several pharmaceutical care related courses are present in current curricula of level 4-7 nurses, its embedding should be extended. Too many students perceive an insufficient preparation to achieve pharmaceutical care competences required in practice. Existing gaps in pharmaceutical care should be addressed to offer more thoroughly prepared nurses to the labour market.

5.
bioRxiv ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38352504

RESUMO

Disturbances in phase transitions and intracellular partitions of nucleocytoplasmic shuttling substrates promote protein aggregation - a hallmark of neurodegenerative diseases. The modular Ran-binding protein 2 (Ranbp2) is a cytosolic molecular hub for rate-limiting steps of disassembly and phase transitions of Ran-GTP-bound protein ensembles exiting nuclear pores. Chaperones also play central roles in phase transitions and proteostasis by suppressing protein aggregation. Ranbp2 haploinsufficiency promotes the age-dependent neuroprotection of the chorioretina against photo-oxidative stress by proteostatic regulations of Ranbp2 substrates and by countering the build-up of poly-ubiquitylated substrates. Further, the peptidyl-prolyl cis-trans isomerase (PPIase) and chaperone activities of the cyclophilin domain (CY) of Ranbp2 modulate the proteostasis of selective neuroprotective substrates, such as hnRNPA2B1, STAT3, HDAC4 or L/M-opsin, while promoting a decline of ubiquitylated substrates. However, links between CY PPIase activity on client substrates and its effect(s) on ubiquitylated substrates are unclear. Here, proteomics of genetically modified mice with deficits of Ranbp2 uncovered the regulation of the small heat shock chaperones - crystallins by Ranbp2 in the chorioretina. Loss of CY PPIase of Ranbp2 up-regulates αA-crystallin proteostasis, which is repressed in non-lenticular tissues. Conversely, the αA-crystallin's substrates, γ-crystallins, are down-regulated by impairment of CY's C-terminal chaperone activity. These CY-dependent effects cause the age-dependent decline of ubiquitylated substrates without overt chorioretinal morphological changes. A model emerges whereby the Ranbp2 CY-dependent remodeling of crystallins' proteostasis subdues molecular aging and preordains chorioretinal neuroprotection by augmenting the chaperone buffering capacity and the decline of ubiquitylated substrates against proteostatic impairments. Further, CY's moonlighting activity holds pan -therapeutic potential against neurodegeneration.

6.
FEBS Lett ; 597(20): 2567-2589, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37597509

RESUMO

Nucleocytoplasmic transport comprises the multistep assembly, transport, and disassembly of protein and RNA cargoes entering and exiting nuclear pores. Accruing evidence supports that impairments to nucleocytoplasmic transport are a hallmark of neurodegenerative diseases. These impairments cause dysregulations in nucleocytoplasmic partitioning and proteostasis of nuclear transport receptors and client substrates that promote intracellular deposits - another hallmark of neurodegeneration. Disturbances in liquid-liquid phase separation (LLPS) between dense and dilute phases of biomolecules implicated in nucleocytoplasmic transport promote micrometer-scale coacervates, leading to proteinaceous aggregates. This Review provides historical and emerging principles of LLPS at the interface of nucleocytoplasmic transport, proteostasis, aging and noxious insults, whose dysregulations promote intracellular aggregates. E3 SUMO-protein ligase Ranbp2 constitutes the cytoplasmic filaments of nuclear pores, where it acts as a molecular hub for rate-limiting steps of nucleocytoplasmic transport. A vignette is provided on the roles of Ranbp2 in nucleocytoplasmic transport and at the intersection of proteostasis in the survival of photoreceptor and motor neurons under homeostatic and pathophysiological environments. Current unmet clinical needs are highlighted, including therapeutics aiming to manipulate aggregation-dissolution models of purported neurotoxicity in neurodegeneration.

7.
Mar Pollut Bull ; 194(Pt A): 115225, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37531796

RESUMO

Brazilian coastal areas have been exposed to various anthropic influences including physical alteration such as marina construction. To assess the impact of the pier marina construction in the Saco da Ribeira cove (Flamengo Bay, SE Brazil), sedimentological (grain size), geochemical (organic and trace elements) parameters and benthic foraminifera were analyzed on a 50-cm-long dated sediment core covering the last century. The multiproxy approach applied to a numerical hydrodynamic model shows that the circulation in the study area underwent an overall reduction (ca. 30 %) after the pier marina construction in the 1970s, promoting an increase of mud accumulation and higher concentrations of total organic carbon and trace elements (i.e., Enrichment Factor Cu from 0.80 to 1.4) as well as a shift in the benthic foraminiferal assemblages (i.e., foraminiferal density from 63 to 23.20 specimens per 10 cm3 and dominance from 0.13 to 0.73). On the basis of these integrated data, better environmental conditions occurred before the 1970s, then an overall increase in environmental stress took place after the pier's marina construction. Our results provide a baseline for future biomonitoring projects in a stressed region and exemplify the strong capability and reliability of benthic foraminifera as bioindicators of paleoenvironmental changes in coastal environments and for understanding how human pressure might induce such changes.


Assuntos
Foraminíferos , Oligoelementos , Humanos , Monitoramento Ambiental/métodos , Sedimentos Geológicos , Brasil , Oligoelementos/análise , Baías , Reprodutibilidade dos Testes
8.
Nurse Educ Pract ; 65: 103485, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36334523

RESUMO

BACKGROUND: Safe pharmaceutical care requires competent nurses with specific knowledge, skills and attitudes. It is unclear whether nursing students are adequately prepared to perform pharmaceutical care in practice. Mapping their pharmaceutical care competences can lead to a better understanding of the extent to which curricula fit expectations of the labour market. OBJECTIVES: To assess pharmaceutical care competences of final-year nursing students of different educational levels. DESIGN: A cross-sectional survey design. SETTINGS: In 14 European countries, nursing schools who offer curricula for level 4 to 7 students were approached. PARTICIPANTS: Through convenience sampling 1741 final-year student nurses of level 4 to 7 were included. Sampling strategies were country-specific. METHODS: A web-platform was developed with an assessment of the level in which students mastered pharmaceutical care competences. Knowledge questions, case studies (basic/advanced level), self-reported practical skills and attitudes were evaluated. RESULTS: Mean scores for knowledge questions differed significantly (p < 0.001) between level 5 (56/100), level 6 (68/100) and level 7 students (72/100). For basic cases level 5 students reached lower scores (64/100) compared with level 6 (71/100) and level 7 (72/100) students (p = 0.002 and p = 0.005). For more advanced cases no difference between levels was observed (overall mean 61/100). Most students (63-90 %) considered themselves skilled to perform pharmaceutical care and had positive attitudes towards their participation in pharmaceutical care (65-97 %). CONCLUSIONS: Relatively low knowledge scores were calculated for final-year student nurses. In some domains, lower levels of students might be insufficiently prepared to take up responsibilities in pharmaceutical care. Our assessment can be used as a tool for educators to evaluate how prepared nursing students are for pharmaceutical care. Its further implementation for students of different educational levels will allow benchmarking between the levels, both within and between countries.


Assuntos
Bacharelado em Enfermagem , Assistência Farmacêutica , Estudantes de Enfermagem , Humanos , Estudos Transversais , Inquéritos e Questionários , Europa (Continente)
9.
Mar Pollut Bull ; 183: 114059, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36029583

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) most likely derived from natural sources were observed in two sediment cores covering the last 100 years in an Amazon estuarine region. A considerable change in the PAHs main source was observed in the 1960s. Before the 1960s, the sources of PAHs seem to be related to biogenic and/or early-diagenetic processes. Concentrations of perylene were higher before the 1960s and suggest that its primary source to the sediments in the Amazon region is linked to a short-term diagenetic transformation of their biogenic precursors. The natural formation of alkylated PAHs in sediments was linked to the methylation of the parental aromatic hydrocarbons due to sediment maturation processes and the dehydrogenation of sterols in the sediments. The relatively rapid reaction occurring in recent sediments of the Amazon region suggests the importance of the microbial community in the transformation of biogenic precursors to alkylated-PAHs in the sediments.


Assuntos
Perileno , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Esteróis , Poluentes Químicos da Água/análise
10.
Environ Pollut ; 253: 981-991, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352190

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHs), including petroleum biomarkers, were studied in four sediment cores collected around Deception and Penguin Islands, Antarctica. Total PAHs in Deception Island (DCP) samples ranged from 2.0 to 26.8 ng g-1, and in Penguin Island (PGI) varied between 13.2 and 60.3 ng g-1. Multiple sources of PAHs were verified in DCP, with petrogenic-derived compounds being predominant over the last 10 years. In PGI, PAHs related to natural contributions from the erosion of coal deposits were reported. Total AHs in DCP ranged from 4.5 to 19 µg g-1 and in PGI varied between 5.3 and 21.9 µg g-1. In DCP, the n-alkanes distribution pattern showed the presence of petroleum residues in the top sections and both terpanes and hopanes were detected, related to the use of fossil fuels for power generation and in different types of vessels. In PGI, the main source of n-alkanes was marine inputs and only terpanes were detected. The slight increase in hydrocarbon levels observed from 1980 onward in DCP was assumed to be due to the development of tourism in the region and to the scientific station activities. In PGI, anthropogenic-related hydrocarbons were detected in the recent sections and were linked to the development of tourism near the island, scientific activities and the increase in vessel traffic. In general, the concentrations of hydrocarbons found around both islands were comparable to those found in uncontaminated Antarctic regions.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos/análise , Alcanos/análise , Regiões Antárticas , Enganação , Ilhas , Petróleo , Hidrocarbonetos Policíclicos Aromáticos/análise
11.
Cell Mol Life Sci ; 76(17): 3407-3432, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30944974

RESUMO

Nucleocytoplasmic transport is dysregulated in sporadic and familial amyotrophic lateral sclerosis (ALS) and retinal ganglion neurons (RGNs) are purportedly involved in ALS. The Ran-binding protein 2 (Ranbp2) controls rate-limiting steps of nucleocytoplasmic transport. Mice with Ranbp2 loss in Thy1+-motoneurons develop cardinal ALS-like motor traits, but the impairments in RGNs and the degree of dysfunctional consonance between RGNs and motoneurons caused by Ranbp2 loss are unknown. This will help to understand the role of nucleocytoplasmic transport in the differential vulnerability of neuronal cell types to ALS and to uncover non-motor endophenotypes with pathognomonic signs of ALS. Here, we ascertain Ranbp2's function and endophenotypes in RGNs of an ALS-like mouse model lacking Ranbp2 in motoneurons and RGNs. Thy1+-RGNs lacking Ranbp2 shared with motoneurons the dysregulation of nucleocytoplasmic transport. RGN abnormalities were comprised morphologically by soma hypertrophy and optic nerve axonopathy and physiologically by a delay of the visual pathway's evoked potentials. Whole-transcriptome analysis showed restricted transcriptional changes in optic nerves that were distinct from those found in sciatic nerves. Specifically, the level and nucleocytoplasmic partition of the anti-apoptotic and novel substrate of Ranbp2, Pttg1/securin, were dysregulated. Further, acetyl-CoA carboxylase 1, which modulates de novo synthesis of fatty acids and T-cell immunity, showed the highest up-regulation (35-fold). This effect was reflected by the activation of ramified CD11b+ and CD45+-microglia, increase of F4\80+-microglia and a shift from pseudopodial/lamellipodial to amoeboidal F4\80+-microglia intermingled between RGNs of naive mice. Further, there was the intracellular sequestration in RGNs of metalloproteinase-28, which regulates macrophage recruitment and polarization in inflammation. Hence, Ranbp2 genetic insults in RGNs and motoneurons trigger distinct paracrine signaling likely by the dysregulation of nucleocytoplasmic transport of neuronal-type selective substrates. Immune-modulators underpinning RGN-to-microglial signaling are regulated by Ranbp2, and this neuronal-glial system manifests endophenotypes that are likely useful in the prognosis and diagnosis of motoneuron diseases, such as ALS.


Assuntos
Microglia/metabolismo , Chaperonas Moleculares/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Células Ganglionares da Retina/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Transporte Ativo do Núcleo Celular , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Modelos Animais de Doenças , Potenciais Evocados/efeitos dos fármacos , Regulação da Expressão Gênica , Metabolismo dos Lipídeos , Metaloproteinases da Matriz Secretadas/genética , Metaloproteinases da Matriz Secretadas/metabolismo , Camundongos , Camundongos Knockout , Chaperonas Moleculares/genética , Neurônios Motores/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/deficiência , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Nervo Óptico/anormalidades , Nervo Óptico/patologia , Comunicação Parácrina , Tamoxifeno/farmacologia , Antígenos Thy-1/genética , Antígenos Thy-1/metabolismo , Transcriptoma
12.
Cell Mol Life Sci ; 76(12): 2275, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30919023

RESUMO

The original version of this article unfortunately contained the following misspelling and formatting mistakes.

13.
Cell Mol Life Sci ; 76(12): 2247-2273, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30742233

RESUMO

The nuclear pore is the gatekeeper of nucleocytoplasmic transport and signaling through which a vast flux of information is continuously exchanged between the nuclear and cytoplasmic compartments to maintain cellular homeostasis. A unifying and organizing principle has recently emerged that cements the notion that several forms of amyotrophic lateral sclerosis (ALS), and growing number of other neurodegenerative diseases, co-opt the dysregulation of nucleocytoplasmic transport and that this impairment is a pathogenic driver of neurodegeneration. The understanding of shared pathomechanisms that underpin neurodegenerative diseases with impairments in nucleocytoplasmic transport and how these interface with current concepts of nucleocytoplasmic transport is bound to illuminate this fundamental biological process in a yet more physiological context. Here, I summarize unresolved questions and evidence and extend basic and critical concepts and challenges of nucleocytoplasmic transport and its role in the pathogenesis of neurodegenerative diseases, such as ALS. These principles will help to appreciate the roles of nucleocytoplasmic transport in the pathogenesis of ALS and other neurodegenerative diseases, and generate a framework for new ideas of the susceptibility of motoneurons, and possibly other neurons, to degeneration by dysregulation of nucleocytoplasmic transport.


Assuntos
Doença dos Neurônios Motores/metabolismo , Doenças Neurodegenerativas/metabolismo , Transporte Ativo do Núcleo Celular , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Citoplasma/metabolismo , Citoplasma/patologia , Humanos , Doença dos Neurônios Motores/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Doenças Neurodegenerativas/patologia
14.
Small GTPases ; 10(2): 146-161, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-28877029

RESUMO

The Ran-binding protein 2 (Ranbp2/Nup358) is a cytoplasmic and peripheral nucleoporin comprised of 4 Ran-GTP-binding domains (RBDs) that are interspersed among diverse structural domains with multifunctional activities. Our prior studies found that the RBD2 and RBD3 of Ranbp2 control mitochondrial motility independently of Ran-GTP-binding in cultured cells, whereas loss of Ran-GTP-binding to RBD2 and RBD3 are essential to support cone photoreceptor development and the survival of mature retinal pigment epithelium (RPE) in mice. Here, we uncover that loss of Ran-GTP-binding to RBD3 alone promotes the robust age-dependent increase of ubiquitylated substrates and S1 subunit (Pmsd1) of the 19S cap of the proteasome in the retina and RPE and that such loss in RBD3 also compromises the structural integrity of the outer segment compartment of cone photoreceptors only and without affecting the viability of these neurons. We also found that the E2-ligase and partner of Ranbp2, ubc9, is localized prominently in the mitochondrial-rich ellipsoid compartment of photoreceptors, where Ranbp2 is also known to localize with and modulate the activity of mitochondrial proteins. However, the natures of Ranbp2 and ubc9 isoforms to the mitochondria are heretofore elusive. Subcellular fractionation, co-immunolocalization and immunoaffinity purification of Ranbp2 complexes show that novel isoforms of Ranbp2 and ubc9 with molecular masses distinct from the large Ranbp2 and unmodified ubc9 isoforms localize specifically to the mitochondrial fraction or associate with mitochondrial components, whereas unmodified and SUMOylated Ran GTPase are excluded from the mitochondrial fraction. Further, liposome-mediated intracellular delivery of an antibody against a domain shared by the mitochondrial and nuclear pore isoforms of Ranbp2 causes the profound fragmentation of mitochondria and their delocalization from Ranbp2 and without affecting Ranbp2 localization at the nuclear pores. Collectively, the data support that Ran GTPase-dependent and independent and moonlighting roles of Ranbp2 or domains thereof and ubc9 control selectively age-dependent, neural-type and mitochondrial functions.


Assuntos
Envelhecimento/metabolismo , Mitocôndrias/metabolismo , Chaperonas Moleculares/química , Chaperonas Moleculares/metabolismo , Neurônios/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/química , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteostase , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina/metabolismo , Proteína ran de Ligação ao GTP/metabolismo , Animais , Camundongos , Domínios Proteicos
15.
Eur J Gastroenterol Hepatol ; 30(8): 959-966, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29727388

RESUMO

BACKGROUND AND OBJECTIVE: Controlled attenuation parameter (CAP) diagnostic performance for steatosis grading has been controversial and considerable observer-related variability in liver biopsy has been reported. This is a subanalysis of a larger chronic hepatitis C study on noninvasive fibrosis staging. MATERIALS AND METHODS: Patients were prospectively enrolled for paired liver biopsy and transient elastography. Biopsy fragments were subjected to digital morphometric steatosis quantification. Associated patient and technical factors, including a newly described elastogram quality score, were evaluated. RESULTS: A total of 312 patients were included in the final analysis. The mean liver stiffness was 8.7±2.1 kPa. Morphometry showed S0 in 19.2% of patients, S1 in 28.5%, S2 in 31.1%, and S3 in 21.2%. CAP showed S0 in 11.2% of patients, S1 in 26.6%, S2 in 56.7%, and S3 in 5.4%. Spearman coefficient showed a positive and independent correlation between CAP and morphometric analysis (r=0.48, P<0.05), except for distinguishing S1 and S2 (P=0.11). Area under the receiver operating characteristic curves for the presence or absence of steatosis was 0.944; differentiation between levels I, II, and III were 0.776, 0.812, and 0.879. Elastogram quality independently predicted accuracy [odds ratio (OR): 6.95, 95% confidence interval (95%CI): 4.45-9.06 as well as CAP interquartile range OR: 2.81, 95%CI: 1.67-3.99] and liver stiffness (OR: 0.78, 95%CI: 0.51-0.80). CONCLUSION: We present an external validation for CAP against the objective steatosis quantification provided by digital morphometry. Fairly good performance indicators were found, except for S1 versus S2 differentiation. Variability and higher liver stiffness were associated with lower performance. Achieving higher quality measurements, however, overcame such limitations with excellent accuracy.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Hepatite C Crônica/diagnóstico por imagem , Hepatite C Crônica/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Adulto , Área Sob a Curva , Biópsia , Distribuição de Qui-Quadrado , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
16.
Sci Total Environ ; 615: 1262-1270, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29751431

RESUMO

The sources and depositional history of OCPs (organochlorine pesticides), PCBs (polychlorinated biphenyls) and PAHs (polycyclic aromatic hydrocarbons) over the last 100years were determined in two sediment cores collected in the Amazon region. It was possible to distinguish two depositional periods along the cores. The first period occurred before extensive anthropogenic effects were registered in the sediments. During this time interval, the concentrations of all OCPs and PCBs were below the detection limits (DL), and the PAH concentrations were low and essentially constant (58.19-124.28ngg-1). The second period starts in the mid-1960s and reflects the increased human influence in the area. The concentrations of OCPs, PCBs, and PAHs increased towards the top of the cores, varying between


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Brasil , Estuários
17.
Plant Physiol Biochem ; 126: 152-162, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29524802

RESUMO

Soil contamination with copper (Cu)-based agrochemicals used in vineyards for pest control is a growing problem. In this context, the application of soil amendment to limit Cu toxicity, especially for young plants after the replanting of vineyards, has been a concern for winemakers. Therefore, the aim of this study was to evaluate how different amendments can contribute to the decrease in Cu availability in areas vocated to viticulture. Furthermore, the aim was to evaluate to the effect of Cu on the biochemical and physiological changes in the development of the young vine plants, both at the shoot and the root level. Vine plants were grown in a greenhouse using a Typic Hapludalf soil characterized by 87.5 mg of Cu kg-1 (control). Three different amendments were applied to the soil: limestone (3 Mg ha-1), calcium silicate (3 Mg ha-1) and vermicompost (30 g of C kg-1). The amendment with vermicompost and calcium silicate caused a significant alkalization of the soil solution. Moreover, specifically for the treatment with vermicompost, the levels of Cu2+ in the soil solution were consistently diminished with a clear benefit for plants (+89% biomass accumulation at the shoot level). In addition, this soil amendment led to a higher photosynthetic rate, lower superoxide dismutase (SOD, EC 1.15.1.1) and guaiacol peroxidase (POD, EC 1.11.1.7) activity and a higher percentage of fine roots with diameter between 0 < L ≥ 0.2 mm (particularly active in water and nutrient acquisition). In conclusion, results showed that vermicompost effectively reduced Cu phytotoxicityin young vines grown in soils with high Cu contents. Furthermore, this amendment might be an asset in enhancing the availability of other important micronutrients such as iron.


Assuntos
Compostos de Cálcio/farmacologia , Cobre , Fazendas , Silicatos/farmacologia , Solo , Vitis/crescimento & desenvolvimento
18.
Int J Phytoremediation ; 19(10): 925-936, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28323446

RESUMO

Efficient N2-fixing Leguminosae nodulating bacteria resistant to As may facilitate plant growth on As-contaminated sites. In order to identify bacteria holding these features, 24 strains were isolated from nodules of the trap species Crotalaria spectabilis (12) and Stizolobium aterrimum (12) growing on an As-contaminated gold mine site. 16S rRNA gene sequencing revealed that most of the strains belonged to the group of α-Proteobacteria, being representatives of the genera Bradyrhizobium, Rhizobium, Inquilinus, Labrys, Bosea, Starkeya, and Methylobacterium. Strains of the first four genera showed symbiotic efficiency with their original host, and demonstrated in vitro specific plant-growth-promoting (PGP) traits (production of organic acids, indole-3-acetic-acid and siderophores, 1-aminocyclopropane-1-carboxylate deaminase activity, and Ca3(PO4)2 solubilization), and increased resistance to As, Zn, and Cd. In addition, these strains and some type and reference rhizobia strains exhibited a wide resistance spectrum to ß-lactam antibiotics. Both intrinsic PGP abilities and multi-element resistance of rhizobia are promising for exploiting the symbiosis with different legume plants on trace-element-contaminated soils.


Assuntos
Arsênio/metabolismo , Bactérias/metabolismo , Fabaceae/microbiologia , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Ouro , Minerais , Mineração , Desenvolvimento Vegetal , Plantas , RNA Ribossômico 16S , Solo , Oligoelementos
19.
Dis Model Mech ; 10(5): 559-579, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28100513

RESUMO

The pathogenic drivers of sporadic and familial motor neuron disease (MND), such amyotrophic lateral sclerosis (ALS), are unknown. MND impairs the Ran GTPase cycle, which controls nucleocytoplasmic transport, ribostasis and proteostasis; however, cause-effect mechanisms of Ran GTPase modulators in motoneuron pathobiology have remained elusive. The cytosolic and peripheral nucleoporin Ranbp2 is a crucial regulator of the Ran GTPase cycle and of the proteostasis of neurological disease-prone substrates, but the roles of Ranbp2 in motoneuron biology and disease remain unknown. This study shows that conditional ablation of Ranbp2 in mouse Thy1 motoneurons causes ALS syndromes with hypoactivity followed by hindlimb paralysis, respiratory distress and, ultimately, death. These phenotypes are accompanied by: a decline in the nerve conduction velocity, free fatty acids and phophatidylcholine of the sciatic nerve; a reduction in the g-ratios of sciatic and phrenic nerves; and hypertrophy of motoneurons. Furthermore, Ranbp2 loss disrupts the nucleocytoplasmic partitioning of the import and export nuclear receptors importin ß and exportin 1, respectively, Ran GTPase and histone deacetylase 4. Whole-transcriptome, proteomic and cellular analyses uncovered that the chemokine receptor Cxcr4, its antagonizing ligands Cxcl12 and Cxcl14, and effector, latent and activated Stat3 all undergo early autocrine and proteostatic deregulation, and intracellular sequestration and aggregation as a result of Ranbp2 loss in motoneurons. These effects were accompanied by paracrine and autocrine neuroglial deregulation of hnRNPH3 proteostasis in sciatic nerve and motoneurons, respectively, and post-transcriptional downregulation of metalloproteinase 28 in the sciatic nerve. Mechanistically, our results demonstrate that Ranbp2 controls nucleocytoplasmic, chemokine and metalloproteinase 28 signaling, and proteostasis of substrates that are crucial to motoneuronal homeostasis and whose impairments by loss of Ranbp2 drive ALS-like syndromes.


Assuntos
Esclerose Lateral Amiotrófica/fisiopatologia , Quimiocinas/metabolismo , Metaloproteinases da Matriz Secretadas/metabolismo , Chaperonas Moleculares/fisiologia , Neurônios Motores/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/fisiologia , Esclerose Lateral Amiotrófica/genética , Animais , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Masculino , Camundongos , Proteostase , Processamento Pós-Transcricional do RNA , Transdução de Sinais/genética
20.
Plant Physiol Biochem ; 106: 253-63, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27209215

RESUMO

Vineyard sandy acid soils from South Brazil have experienced heavy metal contamination due to replacement of copper (Cu)-based by zinc (Zn)-based products to control foliar diseases. Thus, we evaluate physiological and nutritional status of black oat (Avena strigosa Schreb.), a common interrow crop in vineyards from this region. Soil was collected in a natural field from Santana do Livramento, in Rio Grande do Sul, the southernmost state of Brazil. Black oat was cultivated for 30 days in a greenhouse with application of 0, 30, and 60 mg Cu kg(-1) combined with 0, 15, 30, 60, 120, and 180 mg Zn kg(-1). After the trial period, dry matter accumulation of roots and shoots, Cu and Zn contents in roots and shoots, chlorophyll a fluorescence, photosynthetic pigments and catalase (CAT, EC 1.11.1.6) and peroxidase (POD, EC 1.11.1.7) activity were determined. Cu and Zn toxicity was evidenced by the decrease in plant growth of black oat as well as by the decrease of photochemical efficiency associated with the decrease in photosynthetic pigment content, especially with the highest doses of Cu and Zn. Furthermore, the activity of antioxidant enzymes (CAT and POD) was increased in intermediate doses of Zn, indicating the activation of the antioxidant system, but the stress condition in treatments with high levels of Cu and Zn was not reversed.


Assuntos
Avena/crescimento & desenvolvimento , Avena/fisiologia , Cobre/farmacologia , Fenômenos Fisiológicos da Nutrição/efeitos dos fármacos , Solo/química , Zinco/farmacologia , Análise de Variância , Antioxidantes/metabolismo , Avena/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Biomassa , Catalase/metabolismo , Clorofila/metabolismo , Clorofila A , Transporte de Elétrons/efeitos dos fármacos , Fluorescência , Peroxidase/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo
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