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1.
Mol Cell ; 80(5): 764-778.e7, 2020 12 03.
Article in English | MEDLINE | ID: mdl-33207182

ABSTRACT

Autophagy eliminates cytoplasmic content selected by autophagy receptors, which link cargo to the membrane-bound autophagosomal ubiquitin-like protein Atg8/LC3. Here, we report a selective autophagy pathway for protein condensates formed by endocytic proteins in yeast. In this pathway, the endocytic protein Ede1 functions as a selective autophagy receptor. Distinct domains within Ede1 bind Atg8 and mediate phase separation into condensates. Both properties are necessary for an Ede1-dependent autophagy pathway for endocytic proteins, which differs from regular endocytosis and does not involve other known selective autophagy receptors but requires the core autophagy machinery. Cryo-electron tomography of Ede1-containing condensates, at the plasma membrane and in autophagic bodies, shows a phase-separated compartment at the beginning and end of the Ede1-mediated selective autophagy route. Our data suggest a model for autophagic degradation of macromolecular protein complexes by the action of intrinsic autophagy receptors.


Subject(s)
Autophagy-Related Protein 8 Family , Autophagy , Endocytosis , Models, Biological , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Autophagy-Related Protein 8 Family/chemistry , Autophagy-Related Protein 8 Family/metabolism , Cryoelectron Microscopy , Protein Binding , Proteolysis , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/ultrastructure , Saccharomyces cerevisiae Proteins/chemistry , Saccharomyces cerevisiae Proteins/metabolism
2.
Nature ; 586(7831): 796-800, 2020 10.
Article in English | MEDLINE | ID: mdl-32879490

ABSTRACT

Nuclear pore complexes (NPCs) fuse the inner and outer membranes of the nuclear envelope. They comprise hundreds of nucleoporins (Nups) that assemble into multiple subcomplexes and form large central channels for nucleocytoplasmic exchange1,2. How this architecture facilitates messenger RNA export, NPC biogenesis and turnover remains poorly understood. Here we combine in situ structural biology and integrative modelling with correlative light and electron microscopy and molecular perturbation to structurally analyse NPCs in intact Saccharomyces cerevisiae cells within the context of nuclear envelope remodelling. We find an in situ conformation and configuration of the Nup subcomplexes that was unexpected from the results of previous in vitro analyses. The configuration of the Nup159 complex appears critical to spatially accommodate its function as an mRNA export platform, and as a mediator of NPC turnover. The omega-shaped nuclear envelope herniae that accumulate in nup116Δ cells3 conceal partially assembled NPCs lacking multiple subcomplexes, including the Nup159 complex. Under conditions of starvation, herniae of a second type are formed that cytoplasmically expose NPCs. These results point to a model of NPC turnover in which NPC-containing vesicles bud off from the nuclear envelope before degradation by the autophagy machinery. Our study emphasizes the importance of investigating the structure-function relationship of macromolecular complexes in their cellular context.


Subject(s)
Cryoelectron Microscopy , Nuclear Pore/metabolism , Nuclear Pore/ultrastructure , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/ultrastructure , Autophagy , Models, Molecular , Nuclear Pore/chemistry , Nuclear Pore Complex Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Tomography
3.
Proc Natl Acad Sci U S A ; 119(39): e2209823119, 2022 09 27.
Article in English | MEDLINE | ID: mdl-36122245

ABSTRACT

Autophagosomes are unique organelles that form de novo as double-membrane vesicles engulfing cytosolic material for destruction. Their biogenesis involves membrane transformations of distinctly shaped intermediates whose ultrastructure is poorly understood. Here, we combine cell biology, correlative cryo-electron tomography (cryo-ET), and extensive data analysis to reveal the step-by-step structural progression of autophagosome biogenesis at high resolution directly within yeast cells. The analysis uncovers an unexpectedly thin intermembrane distance that is dilated at the phagophore rim. Mapping of individual autophagic structures onto a timeline based on geometric features reveals a dynamical change of membrane shape and curvature in growing phagophores. Moreover, our tomograms show the organelle interactome of growing autophagosomes, highlighting a polar organization of contact sites between the phagophore and organelles, such as the vacuole and the endoplasmic reticulum (ER). Collectively, these findings have important implications for the contribution of different membrane sources during autophagy and for the forces shaping and driving phagophores toward closure without a templating cargo.


Subject(s)
Autophagosomes , Macroautophagy , Vacuoles , Autophagosomes/metabolism , Cell Membrane , Endoplasmic Reticulum/metabolism , Saccharomyces cerevisiae , Vacuoles/metabolism
4.
Ecotoxicol Environ Saf ; 269: 115802, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38091677

ABSTRACT

During respiration, particulate matter with a diameter of 2.5 µm or less (PM2.5) suspended in the atmosphere enters the terminal alveoli and blood. PM2.5 particles can attach to toxic substances, resulting in health problems. Limited information is available regarding the effects of prenatal exposure to water-soluble PM2.5 (WS-PM2.5) and water-insoluble PM2.5 (WI-PM2.5) on male reproduction. In addition, whether exposure to these particles has transgenerational effects remains unknown. We investigated whether prenatal exposure to WS-PM2.5 and WI-PM2.5 disrupts sperm function in generations F1, F2, and F3 of male mice. Pregnant BALB/c mice were treated using intratracheal instillation on gestation days 7, 11, and 15 with 10 mg of a water extract or insoluble PM2.5. On postnatal day 105, epididymal sperm count, motility, morphology, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) production, the sperm chromatin DNA fragmentation index (DFI), and testicular DNA methyltransferase (Dnmt) levels were evaluated in all generations. Whole-genome bisulfite sequencing was used to analyze the DNA methylation status of generation F3. According to the results, exposure to WS-PM2.5 affected sperm morphology, ROS production, and mean DFI in generation F1; ROS production and mean DFI in generation F2; and sperm morphology and MMP in generation F3. Similarly, exposure to WI-PM2.5 affected sperm morphology, ROS production, mean DFI, %DFI, and Dnmt1 expression in generation F1; sperm morphology, MMP, and ROS production in generation F2; and sperm morphology, ROS, and %DFI in generation F3. Two hypermethylated genes, PRR16 and TJP2, were observed in the WS-PM2.5 and WI-PM2.5 groups, two hypomethylated genes, NFATC1 and APOA5, were observed in the WS-PM2.5 group, and two hypomethylated genes, ZFP945 and GSE1, were observed in the WI-PM2.5 group. Hence, prenatal exposure to PM2.5 resulted in transgenerational epigenetic effects, which may explain certain phenotypic changes in male reproduction.


Subject(s)
DNA Methylation , Prenatal Exposure Delayed Effects , Pregnancy , Humans , Female , Mice , Male , Animals , Epigenesis, Genetic , Prenatal Exposure Delayed Effects/metabolism , Reactive Oxygen Species/metabolism , Taiwan , Semen , Spermatozoa , Particulate Matter/metabolism , Water/metabolism
5.
Ophthalmic Physiol Opt ; 43(6): 1500-1509, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37565301

ABSTRACT

PURPOSE: To investigate the incidence rate and risk factors for anisometropia among young schoolchildren. METHODS: A population-based cohort study, the Myopia Investigation Study in Taipei, was conducted in primary schools in Taipei City. Children were recruited for biannual comprehensive eye examinations over 2 years. Cycloplegic autorefraction and slit lamp examinations were performed biannually. Data on demographic information, parental history, lifestyle and near-work activities were collected using parent-administered questionnaires at the first and final visits. Anisometropia was defined as ≥1 D difference in the spherical equivalent (SE) refractive error. RESULTS: A total of 7035 8-year-old children completed the 2-year follow-up evaluations. The average annual incidence of anisometropia was 3.8%. Multivariable logistic regression analysis revealed that baseline SE (odds ratio [OR]: 0.87 95% CI: 0.80-0.95) and female sex (OR: 1.24, 95% confidence interval [CI]: 1.02-1.50) were significantly associated with incident anisometropia. Among lifestyle risk factors, spending <1 h per day in after-school outdoor activities on weekdays (OR: 1.38, 95% CI: 1.08-1.76) and performing near work at a distance <30 cm (OR: 1.33, 95% CI: 1.08-1.64) were significantly associated with an increased risk of incident anisometropia. In the multiple linear regression analysis, the inter-eye difference in SE increased significantly in children performing near work at distances <30 cm (adjusted ß = 0.03; p = 0.02). CONCLUSIONS: This study indicated the annual incidence of anisometropia in Taiwanese schoolchildren. Less time spent outdoors and shorter eye-to-object distances during near work increased the risk of incident anisometropia.


Subject(s)
Anisometropia , Myopia , Child , Humans , Female , Anisometropia/epidemiology , Longitudinal Studies , Cohort Studies , Myopia/epidemiology , Myopia/complications , Risk Factors , Refraction, Ocular , Prevalence
6.
Proc Natl Acad Sci U S A ; 117(2): 1069-1080, 2020 01 14.
Article in English | MEDLINE | ID: mdl-31882451

ABSTRACT

To promote the biochemical reactions of life, cells can compartmentalize molecular interaction partners together within separated non-membrane-bound regions. It is unknown whether this strategy is used to facilitate protein degradation at specific locations within the cell. Leveraging in situ cryo-electron tomography to image the native molecular landscape of the unicellular alga Chlamydomonas reinhardtii, we discovered that the cytosolic protein degradation machinery is concentrated within ∼200-nm foci that contact specialized patches of endoplasmic reticulum (ER) membrane away from the ER-Golgi interface. These non-membrane-bound microcompartments exclude ribosomes and consist of a core of densely clustered 26S proteasomes surrounded by a loose cloud of Cdc48. Active proteasomes in the microcompartments directly engage with putative substrate at the ER membrane, a function canonically assigned to Cdc48. Live-cell fluorescence microscopy revealed that the proteasome clusters are dynamic, with frequent assembly and fusion events. We propose that the microcompartments perform ER-associated degradation, colocalizing the degradation machinery at specific ER hot spots to enable efficient protein quality control.


Subject(s)
Endoplasmic Reticulum-Associated Degradation/physiology , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/ultrastructure , Proteolysis , Chlamydomonas reinhardtii/metabolism , Chlamydomonas reinhardtii/ultrastructure , Cryoelectron Microscopy , Cytosol/metabolism , Endopeptidases , Optical Imaging , Proteasome Endopeptidase Complex/metabolism , Ribosomes/metabolism , Ribosomes/ultrastructure , Valosin Containing Protein/metabolism
7.
Opt Express ; 30(17): 30494-30506, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-36242152

ABSTRACT

In this work, we present high-performance surface plasmonic sensors using gold nanostructures and Bragg photonic structures. The gold film on the Bragg structure provides Tamm plasmon states (TPs). The Fano coupling between higher order TPs and Bloch-wave surface plasmon polariton (BW-SPP) on the gold nanoslit array results in a new hybrid Tamm-plasmon mode. Using finite-difference time-domain calculations, we demonstrate that the hybrid mode has the advantages of high surface sensitivity of BW-SPP mode and high resonant quality of Tamm state. The calculated plasmonic field distribution shows that the hybrid mode has a similar evanescent distribution with BW-SPP mode on gold surface and TPs field in the Bragg structure. The experimental results verify that the hybrid mode has one hundred times higher wavelength sensitivity than the Tamm state. The figure of merit of the hybrid mode is five times better than the BW-SPP mode in conventional nanoslit arrays. The real-time sensorgram further confirms that the hybrid mode has a much higher sensitivity and better signal to noise ratios in the biomolecular interaction measurement.


Subject(s)
Biosensing Techniques , Nanostructures , Biosensing Techniques/methods , Gold/chemistry , Nanostructures/chemistry , Photons , Surface Plasmon Resonance/methods
8.
Mov Disord ; 37(4): 767-777, 2022 04.
Article in English | MEDLINE | ID: mdl-34951052

ABSTRACT

BACKGROUND: Polyglutamine (polyQ) diseases are dominant neurodegenerative diseases caused by an expansion of the polyQ-encoding CAG repeats in the disease-causing gene. The length of the CAG repeats is the major determiner of the age at onset (AO) of polyQ diseases, including Huntington's disease (HD) and spinocerebellar ataxia type 3 (SCA3). OBJECTIVE: We set out to identify common genetic variant(s) that may affect the AO of polyQ diseases. METHODS: Three hundred thirty-seven patients with HD or SCA3 were enrolled for targeted sequencing of 583 genes implicated in proteinopathies. In total, 16 genes were identified as containing variants that are associated with late AO of polyQ diseases. For validation, we further investigate the variants of PIAS1 because PIAS1 is an E3 SUMO (small ubiquitin-like modifier) ligase for huntingtin (HTT), the protein linked to HD. RESULTS: Biochemical analyses revealed that the ability of PIAS1S510G to interact with mutant huntingtin (mHTT) was less than that of PIAS1WT , resulting in lower SUMOylation of mHTT and lower accumulation of insoluble mHTT. Genetic knock-in of PIAS1S510G in a HD mouse model (R6/2) ameliorated several HD-like deficits (including shortened life spans, poor grip strength and motor coordination) and reduced neuronal accumulation of mHTT. CONCLUSIONS: Our findings suggest that PIAS1 is a genetic modifier of polyQ diseases. The naturally occurring variant, PIAS1S510G , is associated with late AO in polyQ disease patients and milder disease severity in HD mice. Our study highlights the possibility of targeting PIAS1 or pathways governing protein homeostasis as a disease-modifying approach for treating patients with HD. © 2021 International Parkinson and Movement Disorder Society.


Subject(s)
Huntington Disease , Proteostasis , Animals , Disease Models, Animal , Humans , Huntingtin Protein/genetics , Huntington Disease/genetics , Huntington Disease/metabolism , Ligases/metabolism , Mice , Peptides , Protein Inhibitors of Activated STAT/genetics , Protein Inhibitors of Activated STAT/metabolism , Small Ubiquitin-Related Modifier Proteins/genetics , Small Ubiquitin-Related Modifier Proteins/metabolism
9.
Age Ageing ; 51(7)2022 07 01.
Article in English | MEDLINE | ID: mdl-35776674

ABSTRACT

BACKGROUND: to assess the efficacy of comprehensive geriatric assessment (CGA) for preventing treatment-related toxicity in older people undergoing non-surgical cancer therapies. METHODS: MEDLINE, EMBASE and Cochrane library databases were searched from inception till January 2022 to identify randomised controlled trials (RCTs) on the incidence of toxicity measured by the Common Terminology Criteria for Adverse Events (primary outcome) and that of therapeutic modifications, early treatment discontinuation, progression-free survival, overall survival and hospitalisation (secondary outcomes). RESULTS: analysis of six RCTs published from 2016 to 2021 recruiting 2,126 participants (median age: 71-77) who received chemotherapy as the major therapeutic approach revealed 51.7% and 64.7% of Grade 3+ toxicity in the CGA and control (i.e. standard care) groups, respectively (RR = 0.81, 95% CI: 0.7-0.94, P = 0.005, I2 = 65%, certainty of evidence [COE]: moderate). There were no significant differences in the incidence of early treatment discontinuation (RR = 0.88, P = 0.47; I2 = 63%,1,408 participants, COE: low), initial reduction in treatment intensity (RR = 0.99, P = 0.94; I2 = 83%, 2055 participants, COE: low), treatment delay (RR = 1.06, P = 0.77, I2 = 0%, 309 participants, COE: moderate), hospitalisation (RR = 0.86, P = 0.39, I2 = 41%, 914 participants, COE: moderate), progression-free and overall survival with or without CGA. However, there was an association between CGA and a lower incidence of dose reduction during treatment (RR = 0.73, P < 0.00001, 956 participants, COE: moderate). CONCLUSIONS: our results demonstrated that comprehensive geriatric assessment may be associated with a lower incidence of treatment-related toxicity and dose reduction compared to standard care in older people receiving non-surgical cancer treatments. Further large-scale studies are warranted to support our findings.


Subject(s)
Geriatric Assessment , Hospitalization , Aged , Humans
10.
Small ; 14(40): e1802133, 2018 10.
Article in English | MEDLINE | ID: mdl-30168661

ABSTRACT

Recent studies indicate that changing the physical properties of lipid bilayers may profoundly change the function of membrane proteins. Here, the effects of dissolved nitrogen and oxygen molecules on the mechanical properties and stability of lipid bilayers are investigated using differential confocal microscopy, atomic force microscopy, and molecular dynamics simulations. All experiments evidence the presence of dissolved air gas in lipid bilayers prepared without gas control. The lipid bilayers in degassed solutions are softer and less stable than those in ambient solutions. High concentrations of nitrogen increase the bending moduli and stability of the lipid bilayers and impede phase separation in ternary lipid bilayers. The effect of oxygen is less prominent. Molecular dynamics simulations indicate that higher nitrogen affinity accounts for increased rigidity. These findings have fundamental and wide implications for phenomena related to lipid bilayers and cell membranes, including the origin of life.


Subject(s)
Lipid Bilayers/chemistry , Microscopy, Atomic Force , Microscopy, Confocal , Molecular Dynamics Simulation , Oxygen/chemistry
11.
J Environ Manage ; 217: 327-336, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29614481

ABSTRACT

High emissions of volatile organic compounds (VOCs) from the petrochemical industry and vehicle exhaust may contribute to high ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP). In this study, the vertical profiles of VOCs were created for the southern Taiwan industrial city of Kaohsiung. Vertical air samples were collected up to 1000 m using an unmanned aerial vehicle (UAV). In Renwu District, VOC distribution was affected by the inversion layer up to 200 m height. Total VOCs (36-327 ppbv), OFP (66-831 ppbv) and SOAFP (0.12-5.55 ppbv) stratified by height were the highest values at 300 m. The VOCs originated from both local and long-distance transport sources. These findings can be integrated into Kaohsiung's future air quality improvement plans and serve as a reference for other industrialized areas worldwide.


Subject(s)
Air Pollutants , Vehicle Emissions , Volatile Organic Compounds , Cities , Environmental Monitoring , Ozone , Photochemistry , Taiwan
12.
Environ Res ; 152: 1-6, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27736685

ABSTRACT

Water damage and moisture in buildings may become more prevalent due to the increasing frequency of extreme precipitation and flooding events resulting from climate change. However, the effects of moisture levels on phthalate emissions from building materials are still underreported. This study aims to evaluate the effect of moisture content (MC) on the level of di-(2ethylhexyl) phthalate (DEHP) emitted from plastic wallpaper (0.22wt% DEHP) within 15 days in a closed chamber. A scenario of short-term exposure to DEHP in buildings suffering from water damage was simulated. Experiments, controlled at 100% relative humidity (RH) of air and 28°C, were conducted under the following three conditions: (I) without wallpaper (control chamber), (II) dry wallpaper (MC at 3.57%) and (III) damp wallpaper (MC at 52.31%). Air and dust samples were collected at the elapsed time of 2, 4, 6, 8, 10, 13 and 15 days, and the wipe sample was collected on the last day. Higher DEHP concentrations were found to be emitted into the air and adsorbed on the dust for wallpapers with higher MC%. DEHP levels in the air exhibited an increasing trend with the length of the experiment. Overall, it was found that approximately 35.31% more total DEHP mass was released into the air, dust and wipe samples from damp wallpapers compared to dry wallpapers. It is concluded that DEHP emissions from plastic materials are affected by the inner moisture percentage.


Subject(s)
Air Pollution, Indoor/analysis , Construction Materials/analysis , Diethylhexyl Phthalate/analysis , Environmental Monitoring , Polyvinyl Chloride/analysis , Water , Taiwan
13.
J Nanobiotechnology ; 14: 9, 2016 Jan 29.
Article in English | MEDLINE | ID: mdl-26821536

ABSTRACT

BACKGROUND: Cell membranes exhibit abundant types of responses to external stimulations. Intuitively, membrane topography should be sensitive to changes of physical or chemical factors in the microenvironment. We employed the non-interferometric wide-field optical profilometry (NIWOP) technique to quantify the membrane roughness of living neuroblastoma cells under various treatments that could change the mechanical properties of the cells. RESULTS: The membrane roughness was reduced as the neuroblastoma cell was treated with paclitaxel, which increases cellular stiffness by translocating microtubules toward the cell membranes. The treatment of positively charged gold nanoparticles (AuNPs) showed a similar effect. In contrast, the negatively charged AuNPs did not cause significant changes of the membrane roughness. We also checked the membrane roughness of fixed cells by using scanning electron microscopy (SEM) and confirmed that the membrane roughness could be regarded as a parameter reflecting cellular mechanical properties. Finally, we monitored the temporal variations of the membrane roughness under the treatment with a hypertonic solution (75 mM sucrose in the culture medium). The membrane roughness was increased within 1 h but returned to the original level after 2 h. CONCLUSIONS: The results in the present study suggest that the optical measurement on membrane roughness can be regarded as a label-free method to monitor the changes in cell mechanical properties or binding properties of nanoparticles on cell surface. Because the cells were left untouched during the measurement, further tests about cell viability or drug efficacy can be done on the same specimen. Membrane roughness could thus provide a quick screening for new chemical or physical treatments on neuronal cells.


Subject(s)
Cell Membrane/drug effects , Gold/administration & dosage , Metal Nanoparticles/administration & dosage , Neuroblastoma/drug therapy , Neurons/drug effects , Paclitaxel/administration & dosage , Animals , Cell Line, Tumor , Mice , Microscopy, Electron, Scanning/methods , Surface Properties
14.
J Biol Chem ; 289(30): 21108-19, 2014 Jul 25.
Article in English | MEDLINE | ID: mdl-24841198

ABSTRACT

Salt-inducible kinase 2 (SIK2) is the only AMP-activated kinase (AMPK) family member known to interact with protein phosphatase 2 (PP2A). However, the functional aspects of this complex are largely unknown. Here we report that the SIK2-PP2A complex preserves both kinase and phosphatase activities. In this capacity,SIK2 attenuates the association of the PP2A repressor, the protein phosphatase methylesterase-1 (PME-1), thus preserving the methylation status of the PP2A catalytic subunit. Furthermore, the SIK2-PP2A holoenzyme complex dephosphorylates and inactivates Ca2(+)/calmodulin-dependent protein kinase I (CaMKI), an upstream kinase for phosphorylating PME-1/Ser(15). The functionally antagonistic SIK2-PP2A and CaMKI and PME-1 networks thus constitute a negative feedback loop that modulates the phosphatase activity of PP2A. Depletion of SIK2 led to disruption of the SIK2-PP2A complex, activation of CaMKI, and downstream effects, including phosphorylation of HDAC5/Ser(259), sequestration of HDAC5 in the cytoplasm, and activation of myocyte-specific enhancer factor 2C (MEF2C)-mediated gene expression. These results suggest that the SIK2-PP2A complex functions in the regulation of MEF2C-dependent transcription. Furthermore, this study suggests that the tightly linked regulatory loop comprised of the SIK2-PP2A and CaMKI and PME-1 networks may function in fine-tuning cell proliferation and stress response.


Subject(s)
Carboxylic Ester Hydrolases/metabolism , Cell Proliferation/physiology , Multienzyme Complexes/metabolism , Protein Phosphatase 2/metabolism , Protein Serine-Threonine Kinases/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Type 1 , Carboxylic Ester Hydrolases/genetics , Cytoplasm/enzymology , Cytoplasm/genetics , Gene Deletion , Gene Expression Regulation/physiology , HEK293 Cells , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Humans , MEF2 Transcription Factors/genetics , MEF2 Transcription Factors/metabolism , Multienzyme Complexes/genetics , Phosphorylation/physiology , Protein Phosphatase 2/genetics , Protein Serine-Threonine Kinases/genetics , Transcription, Genetic/physiology
15.
Environ Pollut ; 342: 123039, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38040182

ABSTRACT

This study investigated the spatiotemporal variation, gas-particle partition, and source resolution of atmospheric speciation mercury (ASM) in Kaohsiung Harbor and neighboring Metro Kaohsiung. Four sampling sites were selected to determine the pollution characteristics and inter-transport of ASM between the port and urban areas. The yearly average GEM, GOM, and PBM concentrations were 7.13 ± 2.2 ng/m3, 331 ± 190 pg/m3, and 532 ± 301 pg/m3, respectively. Notably, GEM emerged as the predominant ASM species (85-94%), primarily originating from anthropogenic emissions from the harbor area and nearby industrial complex. The study revealed a distinct seasonal variation in ASM concentrations in the Kaohsiung Area in the following order: winter > fall > spring > summer. Concerning spatial distribution, ASM concentrations in the port areas were generally higher than those in the urban areas. This disparity was chiefly attributed to the influence of the prevailing winds, local sources, and atmospheric dispersion. Backward trajectory simulation revealed that polluted air masses blown from the northeast in winter and spring, moving along the western in-land part of Taiwan Island, were likely influenced by local sources and long-range transport (LRT). In summer, air pollutants originating from the south were likely transported from the coastal industrial sources. During fall, air masses blown from the western offshore waters transported air pollutants from Kaohsiung Harbor to neighboring Metro Kaohsiung. The results obtained from principle component analysis (PCA) indicated that primary sources in the port areas included ship emissions, vehicular exhausts, and nearby industrial complex, which align with the primary source factors identified by positive matrix factorization (PMF), which were mobile sources and coal-fired industrial boilers. Meanwhile, mobile sources and sulfur-containing fuel/waste combustion were identified as the primary sources in the urban areas.


Subject(s)
Air Pollutants , Air Pollution , Mercury , Mercury/analysis , Environmental Monitoring/methods , Air Pollutants/analysis , Air Pollution/analysis , Vehicle Emissions/analysis , Seasons
16.
Environ Pollut ; 347: 123663, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38428798

ABSTRACT

Fine particulate matter (PM2.5) emitted from marine transportation, bulk materials handling at the docks, and dust dispersion has garnered increased attention, particularly in the interface between port and urban areas. This study explored the inter-transport of PM2.5 between Kaohsiung Harbor and neighboring Metro Kaohsiung. Chemical analyses of PM2.5 samples from four sites include water-soluble ions, metallic elements, carbons, anhydrosugars, and organic acids to establish PM2.5's chemical fingerprints. The CALPUFF air dispersion model is employed to simulate the spatiotemporal distribution of PM2.5 in Kaohsiung Harbor and adjacent urban areas. A clear seasonal and diurnal variation of PM2.5 concentrations and chemical composition was observed in both harbor and urban areas. The high correlation of nighttime PM2.5 levels between the port and urban areas suggests inter-transport phenomena. Sea salt spray, ship emissions, secondary aerosols, and heavy fuel-oil boilers exhibit higher levels in the port area than in the urban area. In Metro Kaohsiung, mobile sources, fugitive dust, and waste incinerators emerge as major PM2.5 contributors. Furthermore, sea breeze significantly influences PM2.5 dispersion from Kaohsiung Harbor to Metro Kaohsiung, particularly in the afternoon. The average contribution of PM2.5 from ships' main engines in Kaohsiung Harbor ranges from 2.9% to 5.3%, while auxiliary engines contribute 3.8%-8.3% of PM2.5 in Metro Kaohsiung.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Ships , Vehicle Emissions/analysis , Environmental Monitoring , Air Pollution/analysis , Particulate Matter/analysis , Dust/analysis , Aerosols/analysis
17.
J Clin Invest ; 134(2)2024 Jan 16.
Article in English | MEDLINE | ID: mdl-37988169

ABSTRACT

Alzheimer's disease is characterized by the accumulation of amyloid-ß plaques, aggregation of hyperphosphorylated tau (pTau), and microglia activation. Galectin-3 (Gal3) is a ß-galactoside-binding protein that has been implicated in amyloid pathology. Its role in tauopathy remains enigmatic. Here, we showed that Gal3 was upregulated in the microglia of humans and mice with tauopathy. pTau triggered the release of Gal3 from human induced pluripotent stem cell-derived microglia in both its free and extracellular vesicular-associated (EV-associated) forms. Both forms of Gal3 increased the accumulation of pathogenic tau in recipient cells. Binding of Gal3 to pTau greatly enhanced tau fibrillation. Besides Gal3, pTau was sorted into EVs for transmission. Moreover, pTau markedly enhanced the number of EVs released by iMGL in a Gal3-dependent manner, suggesting a role of Gal3 in biogenesis of EVs. Single-cell RNA-Seq analysis of the hippocampus of a mouse model of tauopathy (THY-Tau22) revealed a group of pathogenic tau-evoked, Gal3-associated microglia with altered cellular machineries implicated in neurodegeneration, including enhanced immune and inflammatory responses. Genetic removal of Gal3 in THY-Tau22 mice suppressed microglia activation, reduced the level of pTau and synaptic loss in neurons, and rescued memory impairment. Collectively, Gal3 is a potential therapeutic target for tauopathy.


Subject(s)
Galectin 3 , Tauopathies , tau Proteins , Animals , Humans , Mice , Alzheimer Disease/pathology , Disease Models, Animal , Galectin 3/genetics , Galectin 3/metabolism , Induced Pluripotent Stem Cells/metabolism , Mice, Transgenic , Microglia/pathology , tau Proteins/genetics , tau Proteins/metabolism , Tauopathies/genetics , Tauopathies/metabolism
18.
Environ Toxicol ; 28(7): 380-9, 2013 Jul.
Article in English | MEDLINE | ID: mdl-21626651

ABSTRACT

Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants and have been found in human milk in recent years. This study investigates whether prenatal exposure to decabrominated diphenyl ether (BDE-209) induces sperm dysfunction in male offspring. Pregnant CD-1 mice were gavaged once daily with corn oil (control), 10, 500, and 1500 mg kg(-1) body weight of BDE-209 from day 0 of gestation to day 17. The outcomes of male reproductive parameters were assessed on postnatal day 71. Anogenital distance, sperm-head abnormalities, and testicular histopathology were significantly affected in male offspring prenatally exposed to 1500 mg kg(-1). Significant increases in the tendency for sperm DNA denaturation (αT) induction and the DNA fragmentation index (DFI) were found in those exposed to 10, 500, and 1500 mg kg(-1) (P < 0.05). We observed a significant increase of sperm hydrogen peroxide (H(2)O(2)) generation in the 10 and 1500 mg/kg/day groups compared to the control group (P < 0.05). Although our findings suggested that the mechanisms underlying BDE-209-induced sperm DNA damage and H(2)O(2) generation might not be represented as a dose-response relationship, we found that the greater the excess production of sperm H(2)O(2), the greater the sperm αT (r = 0.65, P = 0.0155) and DFI (r = 0.53, P = 0.002). In conclusion, developmental exposure to BDE-209 induced sperm-head abnormality, oxidative stress, chromatin DNA damage, and testicular histopathological changes. These findings suggest that BDE-209-induced male reproductive effects might involve the formation of sperm H(2)O(2) which attacks nucleic acids via H(2)O(2) generation.


Subject(s)
Chromatin/metabolism , DNA Damage , Flame Retardants/toxicity , Halogenated Diphenyl Ethers/toxicity , Maternal Exposure , Prenatal Exposure Delayed Effects/metabolism , Spermatozoa/physiology , Animals , Behavior, Animal/drug effects , Body Weight , Female , Humans , Male , Maternal-Fetal Exchange , Mice , Nucleic Acid Denaturation , Organ Size , Oxidative Stress , Pregnancy , Reactive Oxygen Species , Spermatozoa/pathology , Testis/growth & development , Testis/metabolism , Testis/pathology , Testosterone/blood
19.
Nutrients ; 15(13)2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37447255

ABSTRACT

This meta-analysis aimed to assess the clinical association of the preoperative prognostic nutritional index (pre-PNI) with the risk of postoperative acute kidney injury. Four databases (e.g., Medline) were searched from inception to December 2022 to investigate the association between pre-PNI (i.e., low vs. high) and PO-PNI as well as the correlation between pre-PNI and other postoperative prognostic indices. Overall, 13 observational studies, including 9185 patients, were eligible for analysis. A low PNI was related to increased risks of PO-AKI [odd ratio (OR) = 1.65, p = 0.001, 3811 patients], postoperative infection (OR = 2.1, p < 0.00001, 2291 patients), and mortality (OR = 1.93, p < 0.0001, 2159 patients). Albeit statistically nonsignificant, a trend was noted, linking a low PNI to higher risks of postoperative bleeding (OR = 2.5, p = 0.12, 1157 patients) and stroke (OR = 1.62, p = 0.07, 2036 patients). Pooled results revealed a prolonged intensive care unit (ICU) stay in patients with low PNIs compared to those with high PNIs (MD: 0.98 days, p = 0.02, 2209 patients) without a difference in hospital stay between the two groups (MD: 1.58 days, p = 0.35, 2249 patients). This meta-analysis demonstrated an inverse correlation between PNI and the risks of PO-AKI, postoperative infection, and mortality, as well as the length of ICU stay, which warrants further investigations for verification.


Subject(s)
Acute Kidney Injury , Nutrition Assessment , Humans , Prognosis , Retrospective Studies , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Acute Kidney Injury/etiology , Acute Kidney Injury/complications
20.
APL Bioeng ; 7(1): 016117, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37006781

ABSTRACT

Fibrosis and fibroblast activation usually occur in the tissues surrounding a malignant tumor; therefore, anti-fibrotic drugs are used in addition to chemotherapy. A reliable technique for evaluating the combined effects of anti-fibrotic drugs and anticancer drugs would be beneficial for the development of an appropriate treatment strategy. In this study, we manufactured a three-dimensional (3D) co-culture system of fibroblasts and lung cancer cell spheroids in Matrigel supplemented with fibrin (fibrin/Matrigel) that simulated the tissue microenvironment around a solid tumor. We compared the efficacy of an anticancer drug (cisplatin) with or without pretreatments of two anti-fibrotic drugs, nintedanib and pirfenidone, on the growth and invasion of cancer cells co-cultured with fibroblasts. The results showed that the addition of nintedanib improved cisplatin's effects on suppressing the growth of cancer cell spheroids and the invasion of cancer cells. In contrast, pirfenidone did not enhance the anticancer activity of cisplatin. Nintedanib also showed higher efficacy than pirfenidone in reducing the expression of four genes in fibroblasts associated with cell adhesion, invasion, and extracellular matrix degradation. This study demonstrated that the 3D co-cultures in fibrin/Matrigel would be useful for assessing the effects of drug combinations on tumor growth and invasion.

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