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1.
Semin Thromb Hemost ; 48(3): 382-404, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34624913

RESUMO

The functions of platelets are broad. Platelets function in hemostasis and thrombosis, inflammation and immune responses, vascular regulation, and host defense against invading pathogens, among others. These actions are achieved through the release of a wide set of coagulative, vascular, inflammatory, and other factors as well as diverse cell surface receptors involved in the same activities. As active participants in these physiological processes, platelets become involved in signaling pathways and pathological reactions that contribute to diseases that are defined by inflammation (including by pathogen-derived stimuli), vascular dysfunction, and coagulation. These diseases include Alzheimer's and Parkinson's disease, the two most common neurodegenerative diseases. Despite their unique pathological and clinical features, significant shared pathological processes exist between these two conditions, particularly relating to a central inflammatory mechanism involving both neuroinflammation and inflammation in the systemic environment, but also neurovascular dysfunction and coagulopathy, processes which also share initiation factors and receptors. This triad of dysfunction-(neuro)inflammation, neurovascular dysfunction, and hypercoagulation-illustrates the important roles platelets play in neuropathology. Although some mechanisms are understudied in Alzheimer's and Parkinson's disease, a strong case can be made for the relevance of platelets in neurodegeneration-related processes.


Assuntos
Doença de Alzheimer , Doença de Parkinson , Doença de Alzheimer/metabolismo , Plaquetas/metabolismo , Hemostasia , Humanos , Inflamação , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia
2.
Environ Sci Technol ; 55(19): 13103-13112, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34533942

RESUMO

Reuse of water requires the removal of contaminants to ensure human health. We report the relative estrogenic activity (REA) of reuse treatment design scenarios for water, wastewaters, and processed wastewaters before and after pilot-scale treatment systems tested at select military facilities. The comparative relationships between REA, several composite toxicological endpoints, and spectroscopic indicators were evaluated for different reuse treatment trains. Four treatment processes including conventional and advanced treatments reduced the estrogenicity by at least 33%. Biologically based methods reduced estrogenicity to below detection levels. Conventional treatment scenarios led to significantly less reduction of adverse biological endpoints compared to the advanced treatment scenarios. Incorporating the anaerobic membrane bioreactor reduced more endpoints with higher reduction percentages compared to the sequencing batch reactor design. Membrane technology and advanced oxidation generated reductions across all biological endpoints, from 65% (genotoxicity) to 100% (estrogenicity). The design scenarios featuring a low-cutoff mechanical screen filter, intermittent activated carbon biofilter, and membrane filtration achieved the highest percent reduction and produced water with the lowest negative biological endpoints. Spectroscopic indicators demonstrated case-specific relationships with estrogenicity and toxicity. Estrogenicity consistently correlated with cytotoxicity and thiol reactivity, indicating the potential for preliminary estrogenicity screening using thiol reactivity.


Assuntos
Instalações Militares , Poluentes Químicos da Água , Purificação da Água , Humanos , Proibitinas , Eliminação de Resíduos Líquidos , Águas Residuárias , Água , Poluentes Químicos da Água/toxicidade
3.
Microsc Microanal ; 27(2): 425-436, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33526165

RESUMO

Breast cancer (BC) is one of the most prevalent forms of cancer in women worldwide. Clinical research indicates that BC patients are at an increased risk for thrombotic events, drastically decreasing their quality-of-life and treatment outcomes. There is ample evidence of this in the literature, but it is mainly focused on metastatic BC. Therefore, coagulopathies of nonmetastatic BC are understudied and require in-depth investigation. In this study, clot kinetics and ultrastructure were used to investigate treatment-naïve, nonmetastatic BC patients using scanning electron microscopy, Thromboelastography®, and confocal laser scanning microscopy. It was demonstrated that nonmetastatic BC patients exhibit minimal ultrastructural alterations of the clot components and no changes in the clot kinetics. However, BC patients presented changes to fibrinogen protein structure, compared to matched controls, using an amyloid-selective stain. Together, these findings suggest that coagulation dysfunction(s) in BC patients with early disease manifest at the microlevel, rather than the macrolevel. This study presents novel insights to a method that are more sensitive to coagulation changes in this specific patient group, emphasizing that the coagulation system may react in different forms to the disease, depending on the progression of the disease itself.


Assuntos
Neoplasias da Mama , Trombose , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Feminino , Fibrinogênio/análise , Humanos
4.
Semin Thromb Hemost ; 46(3): 302-319, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32279287

RESUMO

Thrombocytopenia is commonly associated with sepsis and infections, which in turn are characterized by a profound immune reaction to the invading pathogen. Platelets are one of the cellular entities that exert considerable immune, antibacterial, and antiviral actions, and are therefore active participants in the host response. Platelets are sensitive to surrounding inflammatory stimuli and contribute to the immune response by multiple mechanisms, including endowing the endothelium with a proinflammatory phenotype, enhancing and amplifying leukocyte recruitment and inflammation, promoting the effector functions of immune cells, and ensuring an optimal adaptive immune response. During infection, pathogens and their products influence the platelet response and can even be toxic. However, platelets are able to sense and engage bacteria and viruses to assist in their removal and destruction. Platelets greatly contribute to host defense by multiple mechanisms, including forming immune complexes and aggregates, shedding their granular content, and internalizing pathogens and subsequently being marked for removal. These processes, and the nature of platelet function in general, cause the platelet to be irreversibly consumed in the execution of its duty. An exaggerated systemic inflammatory response to infection can drive platelet dysfunction, where platelets are inappropriately activated and face immunological destruction. While thrombocytopenia may arise by condition-specific mechanisms that cause an imbalance between platelet production and removal, this review evaluates a generic large-scale mechanism for platelet depletion as a repercussion of its involvement at the nexus of responses to infection.


Assuntos
Plaquetas/imunologia , Infecções/sangue , Humanos
5.
BMC Bioinformatics ; 20(1): 9, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616525

RESUMO

BACKGROUND: Traditional Map based Cloning approaches, used for the identification of desirable alleles, are extremely labour intensive and years can elapse between the mutagenesis and the detection of the polymorphism. High throughput sequencing based Mapping-by-sequencing approach requires an ordered genome assembly and cannot be used with fragmented, un-scaffolded draft genomes, limiting its application to model species and precluding many important organisms. RESULTS: We addressed this gap in resource and presented a computational method and software implementations called CHERIPIC (Computing Homozygosity Enriched Regions In genomes to Prioritise Identification of Candidate variants). We have successfully validated implementation of CHERIPIC using three different types of bulk segregant sequence data from Arabidopsis, maize and barley, respectively. CONCLUSIONS: CHERIPIC allows users to rapidly analyse bulk segregant sequence data and we have made it available as a pre-packaged binary with all dependencies for Linux and MacOS and as Galaxy tool.


Assuntos
Mapeamento Cromossômico/métodos , Genes de Plantas/genética , Genoma de Planta , Mutação , Polimorfismo de Nucleotídeo Único , Software , Arabidopsis/genética , Cromossomos de Plantas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Homozigoto , Hordeum/genética , Análise de Sequência de DNA/métodos , Zea mays/genética
6.
Am J Physiol Heart Circ Physiol ; 316(5): H1146-H1157, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768357

RESUMO

Although rollout of combined antiretroviral treatment (cART) has blunted human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) onset, there is increased development of cardiovascular diseases (CVDs) in HIV-infected individuals. While most HIV-infected individuals on cART achieve viral suppression, this may not necessarily result in complete immunological recovery. This study therefore evaluated T-cell-mediated changes and coagulation markers in HIV-positive individuals to ascertain their potential to increase CVD risk. Eighty participants were recruited (Worcester, South Africa), and fasted blood was collected to evaluate: 1) immune activation (CD38 expression on CD4+ and CD8+ T cells) and thrombus formation [tissue factor (CD142)] on CD4+ and CD8+ T cells; 2) monocyte subpopulations (nonclassical, intermediate, and classical); and 3) classical regulatory T (Treg) cells with activation markers [glycoprotein A repetitions predominant (GARP) and special AT-rich sequence-binding protein 1 (SATB-1)]. High- and low-density lipoprotein subclasses (Lipoprint) were also determined. This study revealed four key findings for HIV-positive patients: 1) coexpression of the CD142 coagulation marker together with immune activation on both CD4+ and CD8+ T cells during chronic infection stages; 2) Treg cell activation and upregulated GARP and SATB-1 contributing to Treg dysfunction in chronic HIV; 3) proatherogenic monocyte subset expansion with significant correlation between T-cell activation and macrophage activation (marker: CD163); and 4) significant correlation between immune activation and lipid subclasses, revealing crucial changes that can be missed by traditional lipid marker assessments (LDL and HDL). These data also implicate lipopolysaccharide-binding protein as a crucial link between immune activation, lipid alterations, and increased CVD risk. NEW & NOTEWORTHY With combined antiretroviral treatment rollout, HIV-AIDS patients are increasingly associated with cardiovascular diseases onset. This study demonstrated the significant interplay between adaptive immune cell activation and monocyte/macrophage markers in especially HIV-positive individuals with virological failure and on second line treatment. Our data also show a unique link between immune activation and lipid subclass alterations, revealing important changes that can be missed by traditional lipid marker assessments (e.g., LDL and HDL).


Assuntos
Coagulação Sanguínea , Doenças Cardiovasculares/etiologia , Infecções por HIV/complicações , Lipídeos/sangue , Ativação Linfocitária , Monócitos/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/imunologia , Estudos de Casos e Controles , Proliferação de Células , Estudos Transversais , Feminino , Fatores de Transcrição Forkhead/sangue , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Humanos , Ativação de Macrófagos , Masculino , Proteínas de Ligação à Região de Interação com a Matriz/sangue , Proteínas de Membrana/sangue , Pessoa de Meia-Idade , Monócitos/metabolismo , Receptores de Superfície Celular/sangue , Fatores de Risco , Subpopulações de Linfócitos T/metabolismo , Tromboplastina/metabolismo
7.
Environ Sci Technol ; 53(15): 9139-9147, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31283199

RESUMO

Drinking water utilities will increasingly rely on alternative water sources in the future, including wastewater reuse. Safety must be assured in the application of advanced oxidation processes (AOPs) and supporting treatments for wastewater effluent reuse. This study developed toxicological profiles for source and tap waters, wastewaters, and treated effluents by different processes from four military installation locations. The objective of this study was to evaluate the toxicity of extracted organics from diverse source waters and after reuse treatments. The toxicity analyses included thiol reactivity, mammalian cell cytotoxicity, and genotoxicity. Differences in toxicity between source or tap waters and effluents from wastewater treatment processes supported AOP treatment to reduce risks of potable reuse. An anoxic and aerobic activated sludge process followed by sand filtration controlled toxicity to levels similar to a municipal drinking water. An anaerobic membrane bioreactor process exceeded the toxicity levels of a typical drinking water. Two AOP processes (ultraviolet (UV) + reverse osmosis (RO) + chlorination (NaOCl) or RO + UV-H2O2 + NaOCl) significantly reduced toxicity. The integration of the wastewater systems with ultrafiltration, AOP, and RO was effective to reduce the toxicity to levels comparable to, or better than, tap water samples.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Filtração , Peróxido de Hidrogênio , Eliminação de Resíduos Líquidos , Águas Residuárias
8.
Appl Microbiol Biotechnol ; 103(23-24): 9411-9422, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31696282

RESUMO

Cationic polypeptide proteins found in the seeds of the tropical plant Moringa oleifera have coagulation efficiencies similar to aluminum and ferric sulfates without their recalcitrant nature. Although these proteins possess great potential to augment or replace traditional coagulants in water treatment, harvesting active protein from seeds is laborious and not cost-effective. Here, we describe an alternative method to express and secrete active M. oleifera coagulant protein (MO) in Bacillus subtilis. A plasmid library containing the MO gene and 173 different types of secretory signal peptides was created and cloned into B. subtilis strain RIK1285. Fourteen of 440 clones screened were capable of secreting MO with yields ranging from 55 to 122 mg/L of growth medium. The coagulant activity of the highest MO secreting clone was evaluated when grown on Luria broth, and cell-free medium from the culture was shown to reduce turbidity in a buffered kaolin suspension by approximately 90% compared with controls without the MO gene. The clone was also capable of secreting active MO when grown on a defined synthetic wastewater supplemented with 0.5% tryptone. Cell-free medium from the strain harboring the MO gene demonstrated more than a 2-fold reduction in turbidity compared with controls. Additionally, no significant amount of MO was observed without the addition of the synthetic wastewater, suggesting that it served as a source of nutrients for the effective expression and translocation of MO into the medium.


Assuntos
Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Moringa oleifera/química , Proteínas de Plantas/biossíntese , Sementes/química , Coagulantes/metabolismo , Floculação , Microbiologia Industrial , Extratos Vegetais/metabolismo , Águas Residuárias/química , Purificação da Água/métodos
9.
Br J Haematol ; 180(1): 110-117, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29143311

RESUMO

Inflammation, with its associated inflammatory molecules, is integral to most chronic diseases, including the various cardiovascular diseases. Interleukin 12 (IL12) is one of the inflammatory cytokines that is upregulated during inflammation; however, we know very little about its exact effect on red blood cells (RBCs), platelets and fibrin(ogen). IL12 is an important pleiotropic cytokine in early inflammatory responses and has potent immunomodulatory, antitumour and anti-infection activity. Here we investigate how low levels of circulating IL12, comparable to levels found during chronic inflammation, affect coagulation parameters, platelets and RBCs. We used thromboelastography, scanning electron microscopy, refractometery and wide-field microscopy. Our results show that IL12 caused hypercoagulation, platelet activation and spreading, as well as RBC agglutination. This phenomenon has far-reaching implications for treatment of the plethora of conditions where IL12 is upregulated, since it suggests aberrant haemorheology as agglutination affects blood flow. This information might be used in future to target the lowering of IL12 in inflammatory conditions, as well as address RBC agglutination.


Assuntos
Plaquetas/efeitos dos fármacos , Coagulantes/farmacologia , Eritrócitos/efeitos dos fármacos , Fibrinogênio/metabolismo , Interleucina-12/sangue , Interleucina-12/farmacologia , Adolescente , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/ultraestrutura , Técnicas de Imagem por Elasticidade/métodos , Eritrócitos/ultraestrutura , Feminino , Hemorreologia , Humanos , Inflamação/sangue , Inflamação/etiologia , Inflamação/metabolismo , Masculino , Microscopia/métodos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Refratometria , Adulto Jovem
10.
Environ Sci Technol ; 52(15): 8822-8829, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29965743

RESUMO

An in chemico high throughput assay based on N-acetylcysteine was developed and used in conjunction with previous and new mammalian cell cytotoxicity data. Our objective was to derive an empirical equation with confidence levels for mammalian cell cytotoxicity prediction. Modeling data included 16 unique sources of waters and wastewaters of distinct water qualities to encompass a wide range of real environmental samples. This approach provides a quick screen to identify those water and wastewaters that could be prioritized for in depth analytical biological analyses and toxicity. The resulting model can serve as a preliminary convenient tool to screen for potential mammalian cell cytotoxicity in organic extracts of a wide variety of water samples.


Assuntos
Poluentes Químicos da Água , Animais , Compostos de Sulfidrila , Águas Residuárias
11.
Cardiovasc Diabetol ; 16(1): 141, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29096623

RESUMO

BACKGROUND: We have previously shown that many chronic, inflammatory diseases are accompanied, and possibly partly caused or exacerbated, by various coagulopathies, manifested as anomalous clots in the form of 'dense matted deposits'. More recently, we have shown that these clots can be amyloid in nature, and that the plasma of healthy controls can be induced to form such clots by the addition of tiny amounts of bacterial lipopolysaccharide or lipoteichoic acid. Type 2 diabetes (T2D) is also accompanied by raised levels of LPS. METHODS: We use superresolution and confocal microscopies to investigate the amyloid nature of clots from healthy and T2D individuals. RESULTS: We show here, with the established stain thioflavin T and the novel stains Amytracker™ 480 and 680, that the clotting of plasma from type 2 diabetics is also amyloid in nature, and that this may be prevented by the addition of suitable concentrations of LPS-binding protein. CONCLUSION: This implies strongly that there is indeed a microbial component to the development of type 2 diabetes, and suggests that LBP might be used as treatment for it and its sequelae.


Assuntos
Amiloide/sangue , Corantes/metabolismo , Diabetes Mellitus Tipo 2/sangue , Fibrina/metabolismo , Corantes Fluorescentes/metabolismo , Adolescente , Adulto , Idoso , Amiloide/análise , Corantes/análise , Feminino , Fibrina/análise , Corantes Fluorescentes/análise , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Appl Environ Microbiol ; 82(8): 2380-2387, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26873316

RESUMO

Bacillus anthracis, the causative agent of anthrax, was utilized as a bioterrorism agent in 2001 when spores were distributed via the U.S. postal system. In responding to this event, the Federal Bureau of Investigation used traditional bacterial culture viability assays to ascertain the extent of contamination of the postal facilities within 24 to 48 h of environmental sample acquisition. Here, we describe a low-complexity, second-generation reporter phage assay for the rapid detection of viableB. anthracis spores in environmental samples. The assay uses an engineered B. anthracis reporter phage (Wß::luxAB-2) which transduces bioluminescence to infected cells. To facilitate low-level environmental detection and maximize the signal response, expression of luxABin an earlier version of the reporter phage (Wß::luxAB-1) was optimized. These alterations prolonged signal kinetics, increased light output, and improved assay sensitivity. Using Wß::luxAB-2, detection of B. anthracis spores was 1 CFU in 8 h from pure cultures and as low as 10 CFU/g in sterile soil but increased to 10(5)CFU/g in unprocessed soil due to an unstable signal and the presence of competing bacteria. Inclusion of semiselective medium, mediated by a phage-expressed antibiotic resistance gene, maintained signal stability and enabled the detection of 10(4)CFU/g in 6 h. The assay does not require spore extraction and relies on the phage infecting germinating cells directly in the soil sample. This reporter phage displays promise for the rapid detection of low levels of spores on clean surfaces and also in grossly contaminated environmental samples from complex matrices such as soils.


Assuntos
Fagos Bacilares/crescimento & desenvolvimento , Fagos Bacilares/genética , Bacillus anthracis/isolamento & purificação , Bacillus anthracis/virologia , Técnicas Microbiológicas/métodos , Esporos/isolamento & purificação , Esporos/virologia , Microbiologia Ambiental , Genes Reporter , Luciferases/análise , Luciferases/genética , Medições Luminescentes , Sensibilidade e Especificidade , Fatores de Tempo
13.
Biotechnol Bioeng ; 112(7): 1365-75, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25676066

RESUMO

The germination enzyme CwlJ1 plays an important role in degrading the cortex during the germination of Bacillus anthracis spores. However, the specific function and catalytic activity of CwlJ1 remain elusive. Here we report for the first time a detailed in vitro mechanistic study of CwlJ1 expressed in Escherichia coli and its activity against the spore cortical fragments of B. anthracis when added exogenously. CwlJ1 was active on both decoated spores and spore cortical fragments. Through liquid chromatography-mass spectrometry analysis of the digested cortical fragments, we determined that CwlJ1 was a thermostable N-acetylmuramoyl-L-alanine amidase. CwlJ1 mainly recognized large segments of glycan chains in the cortex instead of the minimal structural unit tetrasaccharide, with specificity for muramic acid-δ-lactam-containing glycan chains and preference for the tetrapeptide side chain. Unlike most amidases, CwlJ1 did not appear to contain a divalent cation, as it retained its activity in the presence of EDTA. This study shines some light on the mechanism of spore germination, and provides increased insight into the development of sporicidal enzyme systems for decontamination of B. anthracis and other related bacteria.


Assuntos
Bacillus anthracis/enzimologia , N-Acetil-Muramil-L-Alanina Amidase/genética , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Esporos Bacterianos/metabolismo , Cromatografia Líquida , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Espectrometria de Massas , Polissacarídeos/metabolismo , Especificidade por Substrato
14.
Appl Environ Microbiol ; 79(19): 5899-906, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23872558

RESUMO

There continues to be a need for developing efficient and environmentally friendly treatments for Bacillus anthracis, the causative agent of anthrax. One emerging approach for inactivation of vegetative B. anthracis is the use of bacteriophage endolysins or lytic enzymes encoded by bacterial genomes (autolysins) with highly evolved specificity toward bacterium-specific peptidoglycan cell walls. In this work, we performed in silico analysis of the genome of Bacillus anthracis strain Ames, using a consensus binding domain amino acid sequence as a probe, and identified a novel lytic enzyme that we termed AmiBA2446. This enzyme exists as a homodimer, as determined by size exclusion studies. It possesses N-acetylmuramoyl-l-alanine amidase activity, as determined from liquid chromatography-mass spectrometry (LC-MS) analysis of muropeptides released due to the enzymatic digestion of peptidoglycan. Phylogenetic analysis suggested that AmiBA2446 was an autolysin of bacterial origin. We characterized the effects of enzyme concentration and phase of bacterial growth on bactericidal activity and observed close to a 5-log reduction in the viability of cells of Bacillus cereus 4342, a surrogate for B. anthracis. We further tested the bactericidal activity of AmiBA2446 against various Bacillus species and demonstrated significant activity against B. anthracis and B. cereus strains. We also demonstrated activity against B. anthracis spores after pretreatment with germinants. AmiBA2446 enzyme was also stable in solution, retaining its activity after 4 months of storage at room temperature.


Assuntos
Antibacterianos/metabolismo , Bacillus anthracis/efeitos dos fármacos , Bacillus anthracis/enzimologia , Bacteriólise , Viabilidade Microbiana , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Bacillus anthracis/genética , Bacillus cereus/efeitos dos fármacos , Cromatografia Líquida , Análise por Conglomerados , Hidrólise , Espectrometria de Massas , N-Acetil-Muramil-L-Alanina Amidase/genética , Peptidoglicano/metabolismo , Filogenia , Homologia de Sequência de Aminoácidos
15.
Environ Sci Technol ; 46(21): 12079-87, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-23030462

RESUMO

Ferrate [Fe(VI); FeO(4)(2-)] is an emerging oxidizing agent capable of controlling chemical and microbial water contaminants. Here, inactivation of MS2 coliphage by Fe(VI) was examined. The inactivation kinetics observed in individual batch experiments was well described by a Chick-Watson model with first-order dependences on disinfectant and infective phage concentrations. The inactivation rate constant k(i) at a Fe(VI) dose of 1.23 mgFe/L (pH 7.0, 25 °C) was 2.27(±0.05) L/(mgFe × min), corresponding to 99.99% inactivation at a Ct of ~4 (mgFe × min)/L. Measured k(i) values were found to increase with increasing applied Fe(VI) dose (0.56-2.24 mgFe/L), increasing temperature (5-30 °C), and decreasing pH conditions (pH 6-11). The Fe(VI) dose effect suggested that an unidentified Fe byproduct also contributed to inactivation. Temperature dependence was characterized by an activation energy of 39(±6) kJ mol(-1), and k(i) increased >50-fold when pH decreased from 11 to 6. The pH effect was quantitatively described by parallel reactions with HFeO(4)(-) and FeO(4)(2-). Mass spectrometry and qRT-PCR analyses demonstrated that both capsid protein and genome damage increased with the extent of inactivation, suggesting that both may contribute to phage inactivation. Capsid protein damage, localized in the two regions containing oxidant-sensitive cysteine residues, and protein cleavage in one of the two regions may facilitate genome damage by increasing Fe(VI) access to the interior of the virion.


Assuntos
Desinfetantes/farmacologia , Compostos de Ferro/farmacologia , Levivirus/efeitos dos fármacos , Compostos de Potássio/farmacologia , Purificação da Água/métodos , Proteínas do Capsídeo/metabolismo , Escherichia coli/virologia , Genoma Viral/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Cinética , Levivirus/fisiologia , Modelos Biológicos , Temperatura , Inativação de Vírus/efeitos dos fármacos , Poluentes da Água
16.
Chronic Stress (Thousand Oaks) ; 6: 24705470221076390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35155966

RESUMO

Lipopolysaccharide (LPS) is the main structural component of the outer membrane of most Gram-negative bacteria and has diverse immunostimulatory and procoagulant effects. Even though LPS is well described for its role in the pathology of sepsis, considerable evidence demonstrates that LPS-induced signalling and immune dysregulation are also relevant in the pathophysiology of many diseases, characteristically where endotoxaemia is less severe. These diseases are typically chronic and progressive in nature and span broad classifications, including neurodegenerative, metabolic, and cardiovascular diseases. This Review reappraises the mechanisms of LPS-induced signalling and emphasises the crucial contribution of LPS to the pathology of multiple chronic diseases, beyond conventional sepsis. This perspective asserts that new ways of approaching chronic diseases by targeting LPS-driven pathways may be of therapeutic benefit in a wide range of chronic inflammatory conditions.

17.
Water Res ; 215: 118208, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35255425

RESUMO

Microbial fuel cells (MFCs) can generate electrical energy from the oxidation of the organic matter, but they must be demonstrated at large scales, treat real wastewaters, and show the required performance needed at a site to provide a path forward for this technology. Previous pilot-scale studies of MFC technology have relied on systems with aerated catholytes, which limited energy recovery due to the energy consumed by pumping air into the catholyte. In the present study, we developed, deployed, and tested an 850 L (1400 L total liquid volume) air-cathode MFC treating domestic-type wastewater at a centralized wastewater treatment facility. The wastewater was processed over a hydraulic retention time (HRT) of 12 h through a sequence of 17 brush anode modules (11 m2 total projected anode area) and 16 cathode modules, each constructed using two air-cathodes (0.6 m2 each, total cathode area of 20 m2) with the air side facing each other to allow passive air flow. The MFC effluent was further treated in a biofilter (BF) to decrease the organic matter content. The field test was conducted for over six months to fully characterize the electrochemical and wastewater treatment performance. Wastewater quality as well as electrical energy production were routinely monitored. The power produced over six months by the MFC averaged 0.46 ± 0.35 W (0.043 W m-2 normalized to the cross-sectional area of an anode) at a current of 1.54 ± 0.90 A with a coulombic efficiency of 9%. Approximately 49 ± 15 % of the chemical oxygen demand (COD) was removed in the MFC alone as well as a large amount of the biochemical oxygen demand (BOD5) (70%) and total suspended solid (TSS) (48%). In the combined MFC/BF process, up to 91 ± 6 % of the COD and 91 % of the BOD5 were removed as well as certain bacteria (E. coli, 98.9%; fecal coliforms, 99.1%). The average effluent concentration of nitrate was 1.6 ± 2.4 mg L-1, nitrite was 0.17 ± 0.24 mg L-1 and ammonia was 0.4 ± 1.0 mg L-1. The pilot scale reactor presented here is the largest air-cathode MFC ever tested, generating electrical power while treating wastewater.


Assuntos
Fontes de Energia Bioelétrica , Fontes de Energia Bioelétrica/microbiologia , Eletricidade , Eletrodos , Escherichia coli , Águas Residuárias/microbiologia
18.
Appl Environ Microbiol ; 76(9): 2946-54, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20305026

RESUMO

Free chlorine is an effective disinfectant for controlling adenoviruses in drinking water, but little is known about the underlying inactivation mechanisms. The objective of this study was to elucidate the molecular components of adenovirus type 2 (Ad2) targeted by free chlorine during the inactivation process. The effects of free chlorine treatment on several Ad2 molecular components and associated life cycle events were compared to its effect on the ability of adenovirus to complete its life cycle, i.e., viability. Free chlorine treatment of Ad2 virions did not impair their ability to interact with monoclonal antibodies specific for hexon and fiber proteins of the Ad2 capsid, as measured by enzyme-linked immunosorbent assays, nor did it impair their interaction with recombinant, purified Coxsackie-adenovirus receptor (CAR) proteins in vitro. Free chlorine-treated Ad2 virions also retained their ability to bind to CAR receptors on A549 cell monolayers, despite being unable to form plaques, suggesting that free chlorine inactivates Ad2 by inhibiting a postbinding event of the Ad2 life cycle. DNA isolated from Ad2 virions that had been inactivated by free chlorine was able to be amplified by PCR, indicating that genome damage was not the cause of inactivation. However, inactivated Ad2 virions were unable to express E1A viral proteins during infection of A549 host cells, as measured by using immunoblotting. Collectively, these results indicate that free chlorine inactivates adenovirus by damaging proteins that govern life cycle processes occurring after host cell attachment, such as endocytosis, endosomal lysis, or nuclear delivery.


Assuntos
Adenoviridae/efeitos dos fármacos , Cloro/farmacologia , Desinfetantes/farmacologia , Adenoviridae/genética , Proteínas E1A de Adenovirus/biossíntese , Anticorpos Antivirais/imunologia , Capsídeo/imunologia , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , Ensaio de Imunoadsorção Enzimática , Genes Virais , Viabilidade Microbiana , Receptores Virais/metabolismo
19.
Bioorg Med Chem Lett ; 20(1): 294-8, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19906529

RESUMO

Pursuing our efforts in designing 5-pyrimidylhydroxamic acid anti-cancer agents, we have identified a new series of potent histone deacetylase (HDAC) inhibitors. These compounds exhibit enzymatic HDAC inhibiting properties with IC(50) values in the nanomolar range and inhibit tumor cell proliferation at similar levels. Good solubility, moderate bioavailability, and promising in vivo activity in xenograft model made this series of compounds interesting starting points to design new potent HDAC inhibitors.


Assuntos
Antineoplásicos/química , Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Ácidos Hidroxâmicos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/farmacologia , Camundongos , Camundongos Nus , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Front Immunol ; 11: 1551, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793214

RESUMO

Background:Porphyromonas gingivalis and its inflammagens are associated with a number of systemic diseases, such as cardiovascular disease and type 2 diabetes (T2DM). The proteases, gingipains, have also recently been identified in the brains of Alzheimer's disease patients and in the blood of Parkinson's disease patients. Bacterial inflammagens, including lipopolysaccharides (LPSs) and various proteases in circulation, may drive systemic inflammation. Methods: Here, we investigate the effects of the bacterial products LPS from Escherichia coli and Porphyromonas gingivalis, and also the P. gingivalis gingipain [recombinant P. gingivalis gingipain R1 (RgpA)], on clot architecture and clot formation in whole blood and plasma from healthy individuals, as well as in purified fibrinogen models. Structural analysis of clots was performed using confocal microscopy, scanning electron microscopy, and AFM-Raman imaging. We use thromboelastography® (TEG®) and rheometry to compare the static and dynamic mechanical properties of clots. Results: We found that these inflammagens may interact with fibrin(ogen) and this interaction causes anomalous blood clotting. Conclusions: These techniques, in combination, provide insight into the effects of these bacterial products on cardiovascular health, and particularly clot structure and mechanics.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Cisteína Endopeptidases Gingipaínas/química , Cisteína Endopeptidases Gingipaínas/farmacologia , Fenômenos Mecânicos , Porphyromonas gingivalis/enzimologia , Adulto , Feminino , Fibrina/química , Fibrinogênio/química , Fibrinogênio/ultraestrutura , Humanos , Lipopolissacarídeos/efeitos adversos , Masculino , Microscopia de Força Atômica , Microscopia Confocal , Pessoa de Meia-Idade , Proteínas Recombinantes , Reologia , Análise Espectral Raman , Trombose/tratamento farmacológico , Adulto Jovem
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