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BACKGROUND: Depression and chronic constipation often co-occur, but the reciprocal influence between the two remains unclear. The purpose of this study is to explore the potential association between depression and chronic constipation. METHODS: This study initially utilized data from National Health and Nutrition Examination Survey (NHANES) 2005-2010 to explore the correlation between depression scores and chronic constipation, assessing the non-linear relationship between the two. Subsequently, we conducted a two-sample Mendelian randomization (MR) analysis to evaluate the causal relationship between depression and major depression with chronic constipation. The Inverse Variance Weighting (IVW) method served as the primary reference, supplemented by sensitivity tests. Finally, a reverse MR analysis was performed to assess the presence of any reverse causation. The STROBE-MR checklist for the reporting of MR studies was used in this study. RESULTS: In the NHANES analysis, survey-weighted logistic regression revealed a significantly positive correlation between depression scores and chronic constipation (OR = 1.04, 95% CI = 1.02-1.07, p = 0.002), even after adjusting for the included covariates. The nonlinear analysis using Restricted Cubic Splines (RCS) enhanced the robustness of the association (P-non-liner = 0.01). The MR analysis also confirmed the causal relationship between depression (OR = 11.43, 95% CI = 1.85-70.67, p = 0.008) and major depression (OR = 1.12, 95% CI = 1.03-1.22, p = 0.007) with chronic constipation, passing rigorous sensitivity tests. No evidence of reverse causation was observed in the reverse MR analysis (P > 0.05). CONCLUSIONS: Depression is positively correlated with the risk of chronic constipation. Therefore, enhancing attention to chronic constipation in patients with depression may be effective in clinical practice.
Assuntos
Constipação Intestinal , Análise da Randomização Mendeliana , Inquéritos Nutricionais , Humanos , Constipação Intestinal/epidemiologia , Constipação Intestinal/complicações , Feminino , Doença Crônica , Masculino , Pessoa de Meia-Idade , Adulto , Depressão/epidemiologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/complicações , Idoso , Modelos LogísticosRESUMO
Evaluating lipid profiles in human tissues and biofluids is critical in identifying lipid metabolites in dysregulated metabolic pathways. Due to various chemical characteristics, single-run lipid analysis has not yet been documented. Such approach is essential for analyzing pathology-related lipid metabolites. Age-related macular degeneration, the leading cause of vision loss in western countries, is emblematic of this limitation. Several studies have identified alterations in individual lipids but the majority are based on targeted approaches. In this study, we analyzed and identified approximately 500 lipid species in human biofluids (plasma and erythrocytes) and ocular tissues (retina and retinal pigment epithelium) using the complementarity of hydrophilic interaction liquid chromatography (HILIC) and reversed-phase chromatography (RPC), coupled to high-resolution mass spectrometry. For that, lipids were extracted from human eye globes and blood from 10 subjects and lipidomic analysis was carried out through analysis in HILIC and RPC, alternately. Furthermore, we illustrate the advantages and disadvantages of both techniques for lipid characterization. RPC showed greater sensitivity in hydrophobicity-based lipid separation, detecting diglycerides, triglycerides, cholesterol, and cholesteryl esters, whereas no signal of these molecules was obtained in HILIC. However, due to coelution, RPC was less effective in separating polar lipids like phospholipids, which were separated effectively in HILIC in both ionization modes. The complementary nature of these analytical approaches was essential for the detection and identification of lipid classes/subclasses, which can then provide distinct insights into lipid metabolism, a determinant of the pathophysiology of several diseases involving lipids, notably age-related macular degeneration.
Assuntos
Lipidômica , Degeneração Macular , Humanos , Lipidômica/métodos , Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , FosfolipídeosRESUMO
Retinal melanosome/melanolipofuscin-containing cells (MCCs), clinically visible as hyperreflective foci (HRF) and a highly predictive imaging biomarker for the progression of age-related macular degeneration (AMD), are widely believed to be migrating retinal pigment epithelial (RPE) cells. Using human donor tissue, we identify the vast majority of MCCs as melanophages, melanosome/melanolipofuscin-laden mononuclear phagocytes (MPs). Using serial block-face scanning electron microscopy, RPE flatmounts, bone marrow transplantation and in vitro experiments, we show how retinal melanophages form by the transfer of melanosomes from the RPE to subretinal MPs when the "don't eat me" signal CD47 is blocked. These melanophages give rise to hyperreflective foci in Cd47-/--mice in vivo, and are associated with RPE dysmorphia similar to intermediate AMD. Finally, we show that Cd47 expression in human RPE declines with age and in AMD, which likely participates in melanophage formation and RPE decline. Boosting CD47 expression in AMD might protect RPE cells and delay AMD progression.
Assuntos
Antígeno CD47 , Degeneração Macular , Humanos , Animais , Camundongos , Antígeno CD47/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Degeneração Macular/metabolismo , Retina/metabolismo , Tomografia de Coerência Óptica/métodosRESUMO
The contamination of organoarsenic is becoming increasingly prominent while SR-AOPs were confirmed to be valid for their remediation. This study has found that the novel metal/carbon catalyst (Fe/C-Mn) prepared by solid waste with hierarchical pores could simultaneously degrade roxarsone (ROX) and remove As(V). A total of 95.6% of ROX (20 mg/L) could be removed at the concentration of 1.0 g/L of catalyst and 0.4 g/L of oxidant in the Fe/C-Mn/PMS system within 90 min. The scavenging experiment and electrochemical test revealed that both single-electron and two-electron pathways contributed to the ROX decomposition. Spectroscopic analysis suggested the ROX has been successfully mineralized while As(V) was fixed with the surface Fe and Mn. Density functional theory (DFT) calculation and chromatographic analysis indicated that the As7, N8, O9 and O10 sites of ROX molecule were vulnerable to being attacked by nucleophilic, electrophilic and radical, resulting in the formation of several intermediates such as phenolic compounds. Additionally, the low metal leaching concentration during recycling and high anti-interference ability in various water matrices manifested the practicability of Fe/C-Mn/PMS system.
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Roxarsona , Roxarsona/química , Roxarsona/metabolismo , Manganês , Carvão Vegetal , Metais , EletrólitosRESUMO
BACKGROUND: The risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmission through corneal graft is an ongoing debate and leads to strict restrictions in corneas procurement, leading to a major decrease in eye banking activity. The aims of this study are to specifically assess the capacity of human cornea to be infected by SARS-CoV-2 and promote its replication ex vivo, and to evaluate the real-life risk of corneal contamination by detecting SARS-CoV-2 RNA in corneas retrieved in donors diagnosed with Coronavirus Disease 2019 (COVID-19) and nonaffected donors. METHODS AND FINDINGS: To assess the capacity of human cornea to be infected by SARS-CoV-2, the expression pattern of SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE-2) and activators TMPRSS2 and Cathepsins B and L in ocular surface tissues from nonaffected donors was explored by immunohistochemistry (n = 10 corneas, 78 ± 11 years, 40% female) and qPCR (n = 5 corneas, 80 ± 12 years, 40% female). Additionally, 5 freshly excised corneas (80 ± 12 years, 40% female) were infected ex vivo with highly concentrated SARS-CoV-2 solution (106 median tissue culture infectious dose (TCID50)/mL). Viral RNA was extracted from tissues and culture media and quantified by reverse transcription quantitative PCR (RT-qPCR) (viral RNA copies) 30 minutes (H0) and 24 hours (H24) after infection. To assess the risk of corneal contamination by SARS-CoV-2, viral RNA was tested by RT-qPCR (Ct value) in both corneas and organ culture media from 14 donors diagnosed with COVID-19 (74 ± 10 years, 29% female) and 26 healthy donors (79 ± 13 years, 57% female), and in organ culture media only from 133 consecutive nonaffected donors from 2 eye banks (73 ± 13 years, 29% female). The expression of receptor and activators was variable among samples at both protein and mRNA level. Based on immunohistochemistry findings, ACE-2 was localized mainly in the most superficial epithelial cells of peripheral cornea, limbus, and conjunctiva, whereas TMPRSS2 was mostly expressed in all layers of bulbar conjunctiva. A significant increase in total and positive strands of IP4 RNA sequence (RdRp viral gene) was observed from 30 minutes to 24 hours postinfection in central cornea (1.1 × 108 [95% CI: 6.4 × 107 to 2.4 × 108] to 3.0 × 109 [1.4 × 109 to 5.3 × 109], p = 0.0039 and 2.2 × 107 [1.4 × 107 to 3.6 × 107] to 5.1 × 107 [2.9 × 107 to 7.5 × 107], p = 0.0117, respectively) and in corneoscleral rim (4.5 × 109 [2.7 × 109 to 9.6 × 109] to 3.9 × 1010 [2.6 × 1010 to 4.4 × 1010], p = 0.0039 and 3.1 × 108 [1.2 × 108 to 5.3 × 108] to 7.8 × 108 [3.9 × 108 to 9.9 × 108], p = 0.0391, respectively). Viral RNA copies in ex vivo corneas were highly variable from one donor to another. Finally, viral RNA was detected in 3 out of 28 corneas (11%) from donors diagnosed with COVID-19. All samples from the 159 nonaffected donors were negative for SARS-CoV-2 RNA. The main limitation of this study relates to the limited sample size, due to limited access to donors diagnosed with COVID-19 and concomitant decrease in the procurement corneas from nonaffected donors. CONCLUSIONS: In this study, we observed the expression of SARS-CoV-2 receptors and activators at the human ocular surface and a variable increase in viral RNA copies 24 hours after experimental infection of freshly excised human corneas. We also found viral RNA only in a very limited percentage of donors with positive nasopharyngeal PCR. The low rate of positivity in donors diagnosed with COVID-19 calls into question the utility of donor selection algorithms. TRIAL REGISTRATION: Agence de la Biomédecine, PFS-20-011 https://www.agence-biomedecine.fr/.
Assuntos
COVID-19/complicações , Córnea/virologia , Doenças da Córnea/virologia , Infecções Oculares Virais/virologia , SARS-CoV-2/fisiologia , Adulto , Idoso , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Catepsinas/metabolismo , Chlorocebus aethiops , Córnea/metabolismo , Meios de Cultura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , RNA Viral/metabolismo , Receptores de Coronavírus/metabolismo , Serina Endopeptidases/metabolismo , Células Vero , Replicação ViralRESUMO
Efficient detection of aqueous copper ions is of high significance for environmental and human health, since copper is involved in potent redox activity in physiological and pathological processes. Covalent organic frameworks (COFs) have shown advantages in efficient capturing and detecting of copper ions due to their large surface area, robust chemical stability, and high sensitivity, but most of them are hydrophobic, leading to the limitation in sensing copper ions in aqueous media. Herein, the design and synthesis of an sp2 -carbon conjugated COF (sp2 -TPE-COF) are reported with surfactant-assisted water dispersion for detecting traces of copper ions based on the photo-induced electron transfer (PET) mechanism. Importantly, the olefin-linked conjugated backbone of sp2 -TPE-COF works as a signal amplified transducer for metal ion sensing. Notably, it is found that a surfactant-assisted strategy can greatly enhance COF's dispersion in aqueous solution and finely modulate their sensitivity with a significantly improved KSV to 15.15 × 104 m-1 in SDBS (sodium dodecyl benzene sulfonate) solution, the value of which is larger than that of a majority of COF/MOF based sensors for copper ions. This research demonstrates the promise of surfactant modulated fully π-conjugated COFs for sensing applications.
Assuntos
Corantes Fluorescentes , Estruturas Metalorgânicas , Cobre , Humanos , Estruturas Metalorgânicas/química , Tensoativos , ÁguaRESUMO
In sharp contrast to most previous crisis episodes, the Treasury market experienced severe stress and illiquidity during the COVID-19 crisis, raising concerns that the safe-haven status of US Treasuries may be eroding. We document large shifts in Treasury ownership and temporary accumulation of Treasury and reverse repo positions on dealer balance sheets during this period. We build a dynamic equilibrium asset pricing model in which dealers subject to regulatory balance sheet constraints intermediate demand/supply shocks from habitat agents and provide repo financing to levered investors. The model predicts that Treasury inconvenience yields, measured as the spread between Treasuries and overnight-index swap rates (OIS), as well as spreads between dealers' reverse repo and repo rates, should be highly positive during the COVID-19 crisis, as is confirmed in the data. The same model framework, adapted to the institutional setting in 2007-2009, can also explain the negative Treasury-OIS spread observed during the Great Recession.
RESUMO
Taking low cost silicate minerals to develop efficient Cd2+ adsorption materials was favorable to the comprehensive utilization of minerals and remediation of environmental pollution. In this study, a composite of silicon supported nano iron/aluminum/magnesium (hydr)oxides was prepared with biotite by combining acid leaching and base precipitation process, which was used to remove Cd2+. Cd2+ adsorption behaviors were in accordance of pseudo-second order kinetic model and Langmuir model, and the obtained maximal Cd2+ adsorption capacity was 78.37 mg/g. Increasing pH and temperature could accelerate the removal of Cd2+. The activation energy was calculated as 66.05 kJ/mol, meaning that Cd2+ removal process was mainly depended on chemical adsorption. XRD and SEM results showed that this composite was a micro-nano structure of layered silica supported nano iron/aluminum/magnesium (hydr)oxides. Cd2+ removal mechanisms were consisted of surface complexation and ion exchange between Cd2+ and other metal ions, and the ion exchange interaction played the major role. These results indicated that a novel efficient utilization way for silicate minerals was developed.
Assuntos
Óxidos , Poluentes Químicos da Água , Adsorção , Alumínio , Silicatos de Alumínio , Cádmio , Compostos Ferrosos , Concentração de Íons de Hidrogênio , Ferro , Cinética , Magnésio , Silício , Poluentes Químicos da Água/análiseRESUMO
Human IgA could be from different isotypes (IgA1/IgA2) and/or isoforms (monomeric, dimeric, or secretory). Monomeric IgA mainly IgA1 are considered as an anti-inflammatory isotype whereas dimeric/secretory IgA have clearly dual pro- and anti-inflammatory effects. Here, we show that IgA isotypes and isoforms display different binding abilities to FcαRI, Dectin-1, DC-SIGN, and CD71 on monocyte-derived dendritic cells (moDC). We describe that IgA regulate the expression of their own receptors and trigger modulation of moDC maturation. We also demonstrate that dimeric IgA2 and IgA1 induce different inflammatory responses leading to cytotoxic CD8+ T cells activation. moDC stimulation by dimeric IgA2 was followed by a strong pro-inflammatory effect. Our study highlights differences regarding IgA isotypes and isoforms in the context of DC conditioning. Further investigations are needed on the activation of adaptive immunity by IgA in the context of microbiota/IgA complexes during antibody-mediated immune selection.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Imunoglobulina A/imunologia , Ativação Linfocitária/imunologia , Humanos , Imunoglobulina A/química , Isoformas de ProteínasRESUMO
BACKGROUND: The microbiota plays an important role in host health. Although rubidium (Rb) has been used to study its effects on depression and cancers, the interaction between microbial commensals and Rb is still unexplored. To gain the knowledge of the relationship between Rb and microbes, 51 mice receiving RbCl-based treatment and 13 untreated mice were evaluated for their characteristics and bacterial microbiome changes. RESULTS: The 16S ribosomal RNA gene sequencing of fecal microbiota showed that RbCl generally maintained fecal microbial community diversity, while the shifts in fecal microbial composition were apparent after RbCl exposure. RbCl significantly enhanced the abundances of Rikenellaceae, Alistipes, Clostridium XlVa and sulfate-reducing bacteria including Deltaproteobacteria, Desulfovibrionales, Desulfovibrionaceae and Desulfovibrio, but significantly inhibited the abundances of Tenericutes, Mollicutes, Anaeroplasmatales, Anaeroplasmataceae and Anaeroplasma lineages. With regarding to the archaea, we only observed two less richness archaea Sulfolobus and Acidiplasma at the genus level. CONCLUSIONS: Changes of fecal microbes may in part contribute to the anticancer or anti-depressant effects of RbCl. These findings further validate that the microbiome could be a target for therapeutic intervention.
Assuntos
Bactérias/efeitos dos fármacos , Bactérias/genética , Cloretos/administração & dosagem , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Rubídio/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Bactérias/classificação , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/genética , Masculino , Camundongos , Análise de Sequência de DNA , Organismos Livres de Patógenos EspecíficosRESUMO
Unfractionated heparin (UFH) is a widely used anticoagulant that possess numerous properties including anti-inflammatory, anti-viral, anti-angiogenesis, and anti-metastatic effects. The effect of this drug was evaluated on the podocyte, an important actor of the glomerular filtration. Using a functional approach, we demonstrate that heparin treatment leads to a functional podocyte perturbation characterized by the increase of podocyte monolayer permeability. This effect is enhanced with time of exposure. Proteomic study reveals that heparin down regulate focal adhesion and cytoskeletal protein expressions as well as the synthesis of glomerular basement membrane components. This study clearly demonstrates that UFH may affect podocyte function by altering cytoskeleton organization, cell-cell contacts and cell attachment.
Assuntos
Anticoagulantes/toxicidade , Heparina/toxicidade , Podócitos/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Proteômica , Linhagem Celular , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Adesões Focais/efeitos dos fármacos , Adesões Focais/metabolismo , Adesões Focais/patologia , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Permeabilidade , Fenótipo , Podócitos/metabolismo , Podócitos/patologia , Fatores de TempoRESUMO
Developing novel environmentally materials with high capacity and selectivity for Ag+ adsorption by transforming Ag+ to nano silver is important for the recovery of precious metals from Ag-containing solution. The present study systematically studied the Ag + adsorption process from solution by the composite of SiO2 supported nano ferrous oxalate (SNFO) synthesized from biotite-containing minerals. Batch experiments, dynamics and isothermal adsorption fitting results showed that Ag+ removal behaviours were in accordance with the pseudo-first-order kinetic model and Langmuir model, and the maximal Ag+ removal capacity was 223.68 mg/g. Thermodynamic fitting results suggested that Ag + removal by the composite was a spontaneous and endothermic reaction process. XRD and TEM revealed that the reaction products were consisted of SiO2 and nano silver particles, and FTIR and XPS results indicated that the Ag+ removal mechanisms were attributed to the synergistic reduction interaction between ferrous and the anions of oxalate. Meanwhile, the composite possesses high selectivity for Ag+ removal even at low Ag+ concentration. Moreover, the size of nano silver particles could be adjusted by different pH values. All above results demonstrated that the composite was an ideal material for selective recovery of Ag+ from Ag+ containing effluents in the form of nano silver.
Assuntos
Dióxido de Silício , Poluentes Químicos da Água , Adsorção , Cinética , Oxalatos , Termodinâmica , Poluentes Químicos da Água/análiseRESUMO
In 2013, a clinical trial was initiated to investigate cell therapy for the treatment of corneal endothelial decompensation. Cultivating human corneal endothelial cells (CECs) while maintaining their functional phenotype is challenging; therefore, establishment of a confirmed protocol is pivotal for obtaining approval from regulatory authorities for use of cellular therapy products. In this study, we evaluated organ culture (OC) as a storage method for donor corneas used as a raw material for establishing CEC cultures. OC allows storage of corneal tissue for conventional corneal transplantation at 31-37 °C for up to 5 weeks, whereas storage at 4 °C is limited to 2 weeks. We investigated 20 pairs of corneas: one cornea of each pair was stored in OC and the other in cold storage for one week before CEC culture. In 15/20 cases, the CECs assumed a hexagonal sheet-like monolayer structure and expressed endothelial function-related markers. CECs were also obtained from OC corneas that had been stored for 1 (n = 19) and 2 (n = 7) months. As a further test, CECs were cultivated from 5 OC corneas that had been transported from France to Japan. In all cases, these corneas, even after international transport, generated CECs that formed hexagonal monolayers with clinically applicable and sufficiently high cell densities. In conclusion, the CEC cultures required for endothelial cell therapy can be obtained from OC corneas without changing the standard storage operating procedures of the eye banks.
Assuntos
Córnea , Células Endoteliais , Contagem de Células , Técnicas de Cultura de Células , Endotélio Corneano , Estudos de Viabilidade , Humanos , Técnicas de Cultura de Órgãos , Preservação de ÓrgãosRESUMO
Developing materials from natural minerals to efficiently remove arsenite (As(â ¢)) from solution is vital important for resources comprehensive utilization and environment protection. In this study, biotite containing minerals was used to prepare a novel composite of amino modified silica supported MnO2/Fe-Al hydroxide (SNMFA composite), which was then applied to remove arsenite. Scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated that many amorphous MnO2 and Fe-Al hydroxide nano sheets were loaded on the surface of layered silica structure. Batch experiments showed that this composite could efficiently remove As(â ¢) from aqueous solution, and the maximal removal capacity was identified as 46.11 mg/g. As(â ¢) adsorption behaviours of SNMFA composite were confirmed by the pseudo-second-order kinetic model and Langmuir model, indicating that As(â ¢) adsorption on its surface was monolayer adsorption. The adsorption process was a pH and temperature dependent process, and increasing pH and temperature have facilitated the removal of As(â ¢). Thermodynamic analysis showed that As(â ¢) adsorption process was a spontaneous endothermic reaction. The As(â ¢) removal was mainly relied on the stable inner-sphere coordination model, and the corresponding mechanisms were involved in chelation, precipitation, oxidation-adsorption and electrostatic interaction.
Assuntos
Arsenitos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Silicatos de Alumínio , Compostos Ferrosos , Concentração de Íons de Hidrogênio , Cinética , Compostos de Manganês , Óxidos , Dióxido de Silício , Poluentes Químicos da Água/análiseRESUMO
Liquid deposit mimicking surface aerosolization in the airway is a promising strategy for targeting bronchopulmonary tumors with reduced doses of nanoparticle (NPs). In mimicking and studying such delivery approaches, the use of human in vitro 3D culture models can bridge the gap between 2D cell culture and small animal investigations. Here, we exposed airway epithelia to liquid-apical gadolinium-based AGuIX® NPs in order to determine their safety profile. We used a multiparametric methodology to investigate the NP's distribution over time in both healthy and tumor-bearing 3D models. AGuIX® NPs were able to target tumor cells in the absence of specific surface functionalization, without evidence of toxicity. Finally, we validated the therapeutic potential of this hybrid theranostic AGuIX® NPs upon radiation exposure in this model. In conclusion, 3D cell cultures can efficiently mimic the normal and tumor-bearing airway epitheliums, providing an ethical and accessible model for the investigation of nebulized NPs.
Assuntos
Epitélio/efeitos dos fármacos , Gadolínio/uso terapêutico , Nanopartículas/uso terapêutico , Sistema Respiratório/efeitos dos fármacos , Células A549/patologia , Animais , Técnicas de Cultura de Células , Ciclo Celular , Proliferação de Células , Sistemas de Liberação de Medicamentos/métodos , Gadolínio/química , Humanos , Pulmão , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/químicaRESUMO
Despite of significant progress in remediation of Cr(VI) or Hg(II) pollution by microorganisms, study on the reduction of both Cr(VI) and Hg(II) by the same microbial strain was not reported so far, which is actually important for bioremediation of contaminated sites with multiple heavy metals. In this study, Pseudomonas umsongensis CY-1 was newly isolated from chromium-contaminated soil and showed remediation potentials for both Cr(VI) and Hg(II) pollution. The highest Cr(VI) (93.9%) and Hg(II) (82.8%) reduction rates were obtained at the initial concentration of 5 mg/L. Comparison between removal by resting cells and heat-treated resting cells demonstrated that P. umsongensis CY-1 removed Cr(VI) and Hg(II) from Tris-HCl buffer (pH 7.0) mainly through reduction instead of adsorption. By comparing the Cr(VI) and Hg(II) reduction rates of different cellular fractions, it was found that Cr(VI) and Hg(II) reductions mainly happened in the cytoplasm of P. umsongensis CY-1, which were further demonstrated by Transmission electron microscopy (TEM) analysis. Furthermore, analysis of X-ray photoelectron spectroscopy demonstrated that the reduction products of Cr(VI) and Hg(II) were mainly in the form of Cr(III) and Hg (0), respectively. The findings in this study will provide a guide for further insights in the bioremediation of contaminated sites with multiple heavy metals.
Assuntos
Cromo/análise , Compostos de Mercúrio/análise , Pseudomonas/metabolismo , Poluentes do Solo/análise , Adsorção , Biodegradação Ambiental , Cromo/metabolismo , Compostos de Mercúrio/metabolismo , Modelos Teóricos , Oxirredução , Filogenia , Pseudomonas/isolamento & purificação , Poluentes do Solo/metabolismoRESUMO
Metals in acid mine drainages (AMD) have posed a great threat to environment, and in situ economic environment-friendly remediation technologies need to be developed. Moreover, the effects of acidophiles on biosorption and migrating behaviors of metals in AMD have not been previously reported. In this study, the extremely thermoacidophilic Archaea, Acidianus manzaensis YN25 (A. manzaensis YN25) was used as a bio-adsorbent to adsorb metals (Cu2+, Ni2+, Cd2+ and Zn2+) from acidic solutions which were taken to imitate AMD. The values of their maximum biosorption capacities at both high (1 mM) and low (0.1 mM) metal concentrations followed the order: Cu2+ > Ni2+ > Cd2+ > Zn2+. With the elevations of temperature and pH value, the adsorption amounts of metals increased. The results also indicated that A. manzaensis YN25 had the highest adsorption affinity to Cu2+ in coexisting system of quaternary metals. Acid-base titration data revealed that carboxyl and phosphoryl groups provided adsorption sites for metals via deprotonation. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) further corroborated that amino played an important role in the biosorption process. The fitted Langmuir model illustrated monolayer adsorption occurring on cell surface. The possible adsorption mechanism of A. manzaensis YN25 mainly involved in electrostatic attraction and complexes formation. This study gives a profound insight into the biosorption behavior of heavy metals in acidic solution by thermoacidophilic Archaea and provides a probable novel strategy for in situ remediation of heavy metals pollution in AMD.
Assuntos
Acidianus/fisiologia , Biodegradação Ambiental , Mineração , Poluentes Químicos da Água/metabolismo , Adsorção , Archaea/metabolismo , Íons Pesados , Concentração de Íons de Hidrogênio , Íons , Metais Pesados/análise , Metais Pesados/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análiseRESUMO
Unfractionated heparin (UFH) and low molecular heparin derivatives (LMWH) display numerous biological properties in addition to their anticoagulant effects. However, due to the physicochemical heterogeneity of these drugs, a better understanding concerning their effects on human cells is clearly needed. Considering that heparins are mainly excreted by the kidney, we focused our attention on the effect of UFH and LMWH on human podocytes by functional and morphological/phenotypic in vitro analyses. We demonstrated that these products differentially modulate the permeability of podocyte monolayer to albumin. The functional perturbations observed were correlated to significant cellular morphological and cytoskeletal changes, as well as a decrease in the expression of proteins involved in podocyte adherence to the extracellular matrix or intercellular interactions. This point confirms that UFH and the different LMWHs exert specific effects on podocyte permeability and underlines the need of in vitro tests to evaluate new biological nonanticoagulant properties of LMWH.
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Optimal ex vivo corneal storage in eye banks is crucial to increase both the number of corneas suitable for graft and their intrinsic quality, mainly the number of viable endothelial cells, which dictates graft survival in recipients. With both passive storage methods used worldwide (short-term cold storage in the United States, long-term organ culture in Europe), significant endothelial cell loss is inevitable. Here we show that, with an active storage machine, also called a bioreactor, which restores 2 fundamental physiological parameters, intraocular pressure and medium renewal, endothelial cell survival is improved by 23% compared with organ culture after 4 weeks' storage. Also observed in the bioreactor is a 4-fold higher expression of Na+ /K+ ATPase, which supports one of the major endothelial cell pumping functions. In addition, corneas remain thin and transparent, so they are suitable for surgery at any time. This new active eye banking method may help to reduce the severe global scarcity of donor corneas.
Assuntos
Córnea , Transplante de Córnea , Bancos de Olhos , Preservação de Órgãos/instrumentação , Reatores Biológicos , Sobrevivência Celular , Córnea/citologia , Córnea/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Células Endoteliais/citologia , Células Endoteliais/enzimologia , Desenho de Equipamento , Humanos , Técnicas In Vitro , Técnicas de Cultura de Órgãos/instrumentação , Estudos Prospectivos , ATPase Trocadora de Sódio-Potássio/metabolismo , Fatores de TempoRESUMO
Based on the hypothesis that the X(3872) exotic hadron is a mixture of χ_{c1}(2P) and other states and that its prompt hadroproduction predominately proceeds via its χ_{c1}(2P) component, we calculate the prompt-X(3872) polarization at the CERN LHC through next-to-leading order in α_{s} within the factorization formalism of nonrelativistic QCD, including both the color-singlet ^{3}P_{1}^{[1]} and color-octet ^{3}S_{1}^{[8]} cc[over ¯] Fock states. We also consider the polarization of the J/ψ produced by the subsequent X(3872) decay. We predict that, under ATLAS, CMS, and LHCb experimental conditions, the X(3872) is largely longitudinally polarized, while the J/ψ is largely transversely polarized. We propose that the LHC experiments perform such polarization measurements to pin down the nature of the X(3872) and other X, Y, Z exotic states with nonzero spin.