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1.
J Neurogenet ; : 1-10, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38913811

ABSTRACT

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 (P IP LC), NorpA, and the cyclophilin, NinaA of the fruit fly, Drosophila melanogaster, and their respective mammalian homologues, P I-P LCß4, and cyclophilin-related protein, Ran-binding protein 2 (Ranbp2) in critical biological processes and diseases of photoreceptors and other neurons.

2.
ACS Chem Neurosci ; 15(10): 1967-1989, 2024 05 15.
Article in English | MEDLINE | ID: mdl-38657106

ABSTRACT

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.


Subject(s)
Cyclophilins , Molecular Chaperones , Nuclear Pore Complex Proteins , Peptidylprolyl Isomerase , Proteostasis , Animals , Molecular Chaperones/metabolism , Mice , Cyclophilins/metabolism , Proteostasis/physiology , Peptidylprolyl Isomerase/metabolism , Nuclear Pore Complex Proteins/metabolism , Crystallins/metabolism
3.
BMC Nurs ; 23(1): 96, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38321491

ABSTRACT

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.

4.
bioRxiv ; 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38352504

ABSTRACT

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.

5.
FEBS Lett ; 597(20): 2567-2589, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37597509

ABSTRACT

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.

6.
Mar Pollut Bull ; 194(Pt A): 115225, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37531796

ABSTRACT

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.


Subject(s)
Foraminifera , Trace Elements , Humans , Environmental Monitoring/methods , Geologic Sediments , Brazil , Trace Elements/analysis , Bays , Reproducibility of Results
7.
Nurse Educ Pract ; 65: 103485, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36334523

ABSTRACT

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.


Subject(s)
Education, Nursing, Baccalaureate , Pharmaceutical Services , Students, Nursing , Humans , Cross-Sectional Studies , Surveys and Questionnaires , Europe
8.
Mar Pollut Bull ; 183: 114059, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36029583

ABSTRACT

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.


Subject(s)
Perylene , Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , China , Environmental Monitoring , Estuaries , Geologic Sediments , Polycyclic Aromatic Hydrocarbons/analysis , Sterols , Water Pollutants, Chemical/analysis
9.
Environ Pollut ; 253: 981-991, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31352190

ABSTRACT

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.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Geologic Sediments/chemistry , Hydrocarbons/analysis , Alkanes/analysis , Antarctic Regions , Deception , Islands , Petroleum , Polycyclic Aromatic Hydrocarbons/analysis
10.
Cell Mol Life Sci ; 76(17): 3407-3432, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30944974

ABSTRACT

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.


Subject(s)
Microglia/metabolism , Molecular Chaperones/metabolism , Nuclear Pore Complex Proteins/metabolism , Retinal Ganglion Cells/metabolism , Acetyl-CoA Carboxylase/genetics , Acetyl-CoA Carboxylase/metabolism , Active Transport, Cell Nucleus , Amyotrophic Lateral Sclerosis/metabolism , Amyotrophic Lateral Sclerosis/pathology , Animals , Disease Models, Animal , Evoked Potentials/drug effects , Gene Expression Regulation , Lipid Metabolism , Matrix Metalloproteinases, Secreted/genetics , Matrix Metalloproteinases, Secreted/metabolism , Mice , Mice, Knockout , Molecular Chaperones/genetics , Motor Neurons/metabolism , Nuclear Pore Complex Proteins/deficiency , Nuclear Pore Complex Proteins/genetics , Optic Nerve/abnormalities , Optic Nerve/pathology , Paracrine Communication , Tamoxifen/pharmacology , Thy-1 Antigens/genetics , Thy-1 Antigens/metabolism , Transcriptome
11.
Cell Mol Life Sci ; 76(12): 2275, 2019 06.
Article in English | MEDLINE | ID: mdl-30919023

ABSTRACT

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

12.
Cell Mol Life Sci ; 76(12): 2247-2273, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30742233

ABSTRACT

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.


Subject(s)
Motor Neuron Disease/metabolism , Neurodegenerative Diseases/metabolism , Active Transport, Cell Nucleus , Amyotrophic Lateral Sclerosis/metabolism , Amyotrophic Lateral Sclerosis/pathology , Animals , Cell Nucleus/metabolism , Cell Nucleus/pathology , Cytoplasm/metabolism , Cytoplasm/pathology , Humans , Motor Neuron Disease/pathology , Motor Neurons/metabolism , Motor Neurons/pathology , Neurodegenerative Diseases/pathology
13.
Small GTPases ; 10(2): 146-161, 2019 03.
Article in English | MEDLINE | ID: mdl-28877029

ABSTRACT

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.


Subject(s)
Aging/metabolism , Mitochondria/metabolism , Molecular Chaperones/chemistry , Molecular Chaperones/metabolism , Neurons/metabolism , Nuclear Pore Complex Proteins/chemistry , Nuclear Pore Complex Proteins/metabolism , Proteostasis , Ubiquitin-Conjugating Enzymes/metabolism , Ubiquitin/metabolism , ran GTP-Binding Protein/metabolism , Animals , Mice , Protein Domains
14.
Eur J Gastroenterol Hepatol ; 30(8): 959-966, 2018 08.
Article in English | MEDLINE | ID: mdl-29727388

ABSTRACT

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.


Subject(s)
Elasticity Imaging Techniques/methods , Fatty Liver/diagnostic imaging , Fatty Liver/pathology , Hepatitis C, Chronic/diagnostic imaging , Hepatitis C, Chronic/pathology , Liver/diagnostic imaging , Liver/pathology , Adult , Area Under Curve , Biopsy , Chi-Square Distribution , Female , Humans , Image Interpretation, Computer-Assisted , Logistic Models , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , Prospective Studies , ROC Curve , Reproducibility of Results , Severity of Illness Index
15.
Sci Total Environ ; 615: 1262-1270, 2018 Feb 15.
Article in English | MEDLINE | ID: mdl-29751431

ABSTRACT

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


Subject(s)
Environmental Monitoring , Hydrocarbons, Chlorinated/analysis , Pesticides/analysis , Polychlorinated Biphenyls/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Brazil , Estuaries
16.
Plant Physiol Biochem ; 126: 152-162, 2018 May.
Article in English | MEDLINE | ID: mdl-29524802

ABSTRACT

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.


Subject(s)
Calcium Compounds/pharmacology , Copper , Farms , Silicates/pharmacology , Soil , Vitis/growth & development
17.
Int J Phytoremediation ; 19(10): 925-936, 2017 Oct 03.
Article in English | MEDLINE | ID: mdl-28323446

ABSTRACT

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.


Subject(s)
Arsenic/metabolism , Bacteria/metabolism , Fabaceae/microbiology , Soil Pollutants/metabolism , Biodegradation, Environmental , Gold , Minerals , Mining , Plant Development , Plants , RNA, Ribosomal, 16S , Soil , Trace Elements
18.
Dis Model Mech ; 10(5): 559-579, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28100513

ABSTRACT

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.


Subject(s)
Amyotrophic Lateral Sclerosis/physiopathology , Chemokines/metabolism , Matrix Metalloproteinases, Secreted/metabolism , Molecular Chaperones/physiology , Motor Neurons/metabolism , Nuclear Pore Complex Proteins/physiology , Amyotrophic Lateral Sclerosis/genetics , Animals , Cell Nucleus/metabolism , Cytoplasm/metabolism , Female , Male , Mice , Proteostasis , RNA Processing, Post-Transcriptional , Signal Transduction/genetics
19.
Plant Physiol Biochem ; 106: 253-63, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27209215

ABSTRACT

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.


Subject(s)
Avena/growth & development , Avena/physiology , Copper/pharmacology , Nutritional Physiological Phenomena/drug effects , Soil/chemistry , Zinc/pharmacology , Analysis of Variance , Antioxidants/metabolism , Avena/drug effects , Biological Transport/drug effects , Biomass , Catalase/metabolism , Chlorophyll/metabolism , Chlorophyll A , Electron Transport/drug effects , Fluorescence , Peroxidase/metabolism , Photosynthesis/drug effects , Photosystem II Protein Complex/metabolism , Plant Development/drug effects , Plant Roots/drug effects , Plant Roots/metabolism , Plant Shoots/drug effects , Plant Shoots/metabolism
20.
Ecotoxicol Environ Saf ; 129: 109-19, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27011111

ABSTRACT

The occurrence of high levels of Cu in vineyard soils is often the result of intensive use of fungicides for the preventive control of foliar diseases and can cause toxicity to plants. Nowadays many grape growers in Southern Brazil have replaced Cu-based with Zn-based products. The aim of the study was to evaluate whether the increase in Zn concentration in a soil with high Cu contents can interfere with the dynamics of these elements, and if this increase in Zn may cause toxicity to maize (Zea mays L.). Soil samples were collected in two areas, one in a vineyard with more than 30 years of cultivation and high concentration of Cu and the other on a natural grassland area adjacent to the vineyard. Different doses of Cu and Zn were added to the soil, and the adsorption isotherms were built following the Langmuir's model. In a second experiment, the vineyard soil was spiked with different Zn concentrations (0, 30, 60, 90, 180, and 270mg Zn kg(-1)) in 3kg pots where maize was grown in a greenhouse for 35 days. When Cu and Zn were added together, there was a reduction in the quantities adsorbed, especially for Zn. Zn addition decreased the total plant dry matter and specific leaf mass. Furthermore, with the increase in the activity of catalase, an activation of the antioxidant system was observed. However, the system was not sufficiently effective to reverse the stress levels imposed on soil, especially in plants grown in the highest doses of Zn. At doses higher than 90Znmgkg(-1) in the Cu-contaminated vineyard soil, maize plants were no longer able to activate the protection mechanism and suffered from metal stress, resulting in suppressed dry matter yields due to impaired functioning of the photosynthetic apparatus and changes in the enzymatic activity of plants. Replacement of Cu- by Zn-based fungicides to avoid Cu toxicity has resulted in soil vineyards contaminated with these metals and damaging of plant photosynthetic apparatus and enzyme activity.


Subject(s)
Copper , Soil Pollutants , Zea mays/drug effects , Zinc , Adsorption , Brazil , Copper/chemistry , Copper/toxicity , Farms , Fungicides, Industrial , Plant Leaves/drug effects , Plant Leaves/growth & development , Soil/chemistry , Soil Pollutants/chemistry , Soil Pollutants/toxicity , Vitis , Zea mays/growth & development , Zinc/chemistry , Zinc/toxicity
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