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1.
Orthop J Sports Med ; 11(11): 23259671231204851, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954863

RESUMO

Background: Superior labral anterior and posterior (SLAP) tears are a common finding in overhead athletes. The original classification system produced by Snyder in 1990 contained 4 types of SLAP tears and was later expanded to 10 types. The classification has been challenging because of inconsistencies between surgeons making diagnoses and treatments based on the diagnosis. Furthermore, patient factors-such as age and sports played-affect the treatment algorithms, even across similarly classified SLAP tears. Purpose: To (1) assess the interobserver and intraobserver reliability of the Snyder and expanded SLAP (ESLAP) classification systems and (2) determine the consistency of treatment for a given SLAP tear depending on different clinical scenarios. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 20 arthroscopic surgical videos and magnetic resonance imaging scans of patients with SLAP tears were sent to 20 orthopaedic sports medicine surgeons at various stages of training. Surgeons were asked to identify the type of SLAP tear using the Snyder and ESLAP classifications. Surgeons were then asked to determine the treatment for a SLAP tear using 4 clinical scenarios: (1) in the throwing arm of an 18-year-old pitcher; (2) in the dominant arm of an 18-year-old overhead athlete; (3) a 35-year-old overhead athlete; (4) or a 50-year-old overhead athlete. Responses were recorded, and the cases were shuffled and sent back 6 weeks after the initial responses. Results were then analyzed using the Fleiss kappa coefficient (κ) to determine interobserver and intraobserver degrees of agreement. Results: There was moderate intraobserver reliability in both the Snyder and ESLAP classifications (κ = 0.52) and fair interobserver reliability for both classification systems (Snyder, κ = 0.31; ESLAP, κ = 0.30; P < .0001) among all surgeons. Additionally, there was only fair agreement (κ = 0.30; P < .0001) for the treatment modalities chosen by the reviewers for each case. Conclusion: This study demonstrated that SLAP tears remain a challenging problem for orthopaedic surgeons in diagnostics and treatment plans. Therefore, care should be taken in the preoperative discussion with the patient to consider all the possible treatment options because this may affect the postoperative recovery period and patient expectations.

2.
Adv Healthc Mater ; 12(13): e2202729, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36689343

RESUMO

Despite the availability of licensed vaccines, influenza causes considerable morbidity and mortality worldwide. Current influenza vaccines elicit an immune response that primarily targets the head domain of the viral glycoprotein hemagglutinin (HA). Influenza viruses, however, readily evade this response by acquiring mutations in the head domain. While vaccines that target the more conserved HA stalk may circumvent this problem, low levels of antistalk antibodies are elicited by vaccination, possibly due to the poor accessibility of the stalk domain to B cell receptors. In this work, it is demonstrated that nanoparticles presenting HA in an inverted orientation generate tenfold higher antistalk antibody titers after a prime immunization and fivefold higher antistalk titers after a boost than nanoparticles displaying HA in its regular orientation. Moreover, nanoparticles presenting HA in an inverted orientation elicit a broader antistalk response that reduces mouse weight loss and improves survival after challenge to a greater extent than nanoparticles displaying HA in a regular orientation. Refocusing the antibody response toward conserved epitopes by controlling antigen orientation may enable the design of broadly protective nanovaccines targeting influenza viruses and other pathogens with pandemic potential.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Camundongos , Animais , Humanos , Hemaglutininas , Anticorpos Antivirais , Formação de Anticorpos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
3.
EBioMedicine ; 86: 104341, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36375316

RESUMO

BACKGROUND: The COVID-19 pandemic continues to cause morbidity and mortality worldwide. Most approved COVID-19 vaccines generate a neutralizing antibody response that primarily targets the highly variable receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein. SARS-CoV-2 "variants of concern" have acquired mutations in this domain allowing them to evade vaccine-induced humoral immunity. Recent approaches to improve the breadth of protection beyond SARS-CoV-2 have required the use of mixtures of RBD antigens from different sarbecoviruses. It may therefore be beneficial to develop a vaccine in which the protective immune response targets a more conserved region of the S protein. METHODS: Here we have developed a vaccine based on the conserved S2 subunit of the S protein and optimized the adjuvant and immunization regimen in Syrian hamsters and BALB/c mice. We have characterized the efficacy of the vaccine against SARS-CoV-2 variants and other coronaviruses. FINDINGS: Immunization with S2-based constructs elicited a broadly cross-reactive IgG antibody response that recognized the spike proteins of not only SARS-CoV-2 variants, but also SARS-CoV-1, and the four endemic human coronaviruses. Importantly, immunization reduced virus titers in respiratory tissues in vaccinated animals challenged with SARS-CoV-2 variants B.1.351 (beta), B.1.617.2 (delta), and BA.1 (omicron) as well as a pangolin coronavirus. INTERPRETATION: These results suggest that S2-based constructs can elicit a broadly cross-reactive antibody response resulting in limited virus replication, thus providing a framework for designing vaccines that elicit broad protection against coronaviruses. FUNDING: NIH, Japan Agency for Medical Research and Development, Garry Betty/ V Foundation Chair Fund, and NSF.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Camundongos , Humanos , SARS-CoV-2/genética , Vacinas Combinadas , Vacinas contra COVID-19 , Pangolins , Pandemias , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Anticorpos Antivirais
4.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 10): 982-988, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34667623

RESUMO

Structural analyses of the compounds di-µ-acetato-κ4 O:O'-bis-{[2-meth-oxy-N,N-bis-(quinolin-2-ylmeth-yl)ethanamine-κ4 N,N',N'',O]manganese(II)} bis-(tetra-phen-yl-borate) di-chloro-methane 1.45-solvate, [Mn2(C23O2)2(C23H23N3O)2](C24H20B)·1.45CH2Cl2 or [Mn(DQMEA)(µ-OAc)2Mn(DQMEA)](BPh4)2·1.45CH2Cl2 or [1](BPh4)2·1.45CH2Cl2, and (acetato-κO)[2-hy-droxy-N,N-bis(quinolin-2-ylmeth-yl)ethanamine-κ4 N,N',N'',O](methanol-κO)manganese(II) tetra-phenyl-borate methanol monosolvate, [Mn(CH3COO)(C22H21N3O)(CH3OH)](C24H20B)·CH3OH or [Mn(DQEA)(OAc)(CH3OH)]BPh4·CH3OH or [2]BPh4·CH3OH, by single-crystal X-ray diffraction reveal distinct differences in the geometry of coordination of the tripodal DQEA and DQMEA ligands to MnII ions. In the asymmetric unit, compound [1](BPh4)2·(CH2Cl2)1.45 crystallizes as a dimer in which each manganese(II) center is coordinated by the central amine nitro-gen, the nitro-gen atom of each quinoline group, and the meth-oxy-oxygen of the tetra-dentate DQMEA ligand, and two bridging-acetate oxygen atoms. The symmetric MnII centers have a distorted, octa-hedral geometry in which the quinoline nitro-gen atoms are trans to each other resulting in co-planarity of the quinoline rings. For each MnII center, a coordinated acetate oxygen participates in C-H⋯O hydrogen-bonding inter-actions with the two quinolyl moieties, further stabilizing the trans structure. Within the crystal, weak π-π stacking inter-actions and inter-molecular cation-anion inter-actions stabilize the crystal packing. In the asymmetric unit, compound [2]BPh4·CH3OH crystallizes as a monomer in which the manganese(II) ion is coordinated to the central nitro-gen, the nitro-gen atom of each quinoline group, and the alcohol oxygen of the tetra-dentate DQEA ligand, an oxygen atom of OAc, and the oxygen atom of a methanol ligand. The geometry of the MnII center in [2]BPh4·CH3OH is also a distorted octa-hedron, but the quinoline nitro-gen atoms are cis to each other in this structure. Hydrogen bonding between the acetate oxygen atoms and hydroxyl (O-H⋯O) and quinolyl (C-H⋯O and N-H⋯O) moieties of the DQEA ligand stabilize the complex in this cis configuration. Within the crystal, dimerization of complexes occurs by the formation of a pair of inter-molecular O3-H3⋯O2 hydrogen bonds between the coordinated hydroxyl oxygen of the DQEA ligand of one complex and an acetate oxygen of another. Additional hydrogen-bonding and inter-molecular cation-anion inter-actions contribute to the crystal packing.

5.
Bioeng Transl Med ; 6(3): e10253, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34589610

RESUMO

The persistence of the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has brought to the forefront the need for safe and effective vaccination strategies. In particular, the emergence of several variants with greater infectivity and resistance to current vaccines has motivated the development of a vaccine that elicits a broadly neutralizing immune response against all variants. In this study, we used a nanoparticle-based vaccine platform for the multivalent display of the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein, the primary target of neutralizing antibodies. Multiple copies of RBD were conjugated to the SpyCatcher-mi3 protein nanoparticle to produce a highly immunogenic nanoparticle-based vaccine. RBD-SpyCatcher-mi3 vaccines elicited broadly cross-reactive antibodies that recognized the spike proteins of not just an early isolate of SARS-CoV-2, but also three SARS-CoV-2 variants of concern as well as SARS-CoV-1. Moreover, immunization elicited high neutralizing antibody titers against an early isolate of SARS-CoV-2 as well as four variants of concern, including the delta variant. These results reveal the potential of RBD-SpyCatcher-mi3 as a broadly protective vaccination strategy.

6.
Commun Biol ; 4(1): 597, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011948

RESUMO

The COVID-19 pandemic continues to wreak havoc as worldwide SARS-CoV-2 infection, hospitalization, and death rates climb unabated. Effective vaccines remain the most promising approach to counter SARS-CoV-2. Yet, while promising results are emerging from COVID-19 vaccine trials, the need for multiple doses and the challenges associated with the widespread distribution and administration of vaccines remain concerns. Here, we engineered the coat protein of the MS2 bacteriophage and generated nanoparticles displaying multiple copies of the SARS-CoV-2 spike (S) protein. The use of these nanoparticles as vaccines generated high neutralizing antibody titers and protected Syrian hamsters from a challenge with SARS-CoV-2 after a single immunization with no infectious virus detected in the lungs. This nanoparticle-based vaccine platform thus provides protection after a single immunization and may be broadly applicable for protecting against SARS-CoV-2 and future pathogens with pandemic potential.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/imunologia , COVID-19/prevenção & controle , Pandemias , SARS-CoV-2 , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/imunologia , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Imunização/métodos , Levivirus/genética , Levivirus/imunologia , Mesocricetus , Microscopia Eletrônica de Transmissão , Modelos Animais , Nanopartículas/administração & dosagem , Nanopartículas/ultraestrutura , Nanotecnologia , Pandemias/prevenção & controle , Engenharia de Proteínas , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/administração & dosagem , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/genética , Vacinas Combinadas/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
7.
Adv Healthc Mater ; 10(4): e2000714, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32755047

RESUMO

Respiratory syncytial virus (RSV), for which there is currently no licensed vaccine, displays a fusion (F) protein that is considered a vaccine target. This protein has an antigenic site called site Ø, which has been shown to elicit potent, neutralizing antibodies and has therefore been considered important in the formulation of RSV vaccines. However, this site is also the least conserved region on the F protein across RSV subtypes. Therefore, directing the immune response away from site Ø and refocusing it toward more conserved parts of the RSV F protein might serve to better elicit broadly neutralizing antibodies. To demonstrate that directing the immune response away from site Ø is a viable approach, a prefusion F-based vaccine based on an F protein with a shielded site Ø is generated. Sera from mice immunized with multivalent scaffolds presenting this immunogen is capable of neutralizing RSV of both subtypes. This result may have application in the development of an effective and broadly protective RSV vaccine.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Animais , Anticorpos Antivirais , Camundongos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Proteínas Virais de Fusão/genética
8.
Chem Commun (Camb) ; 56(25): 3685-3688, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32119023

RESUMO

Fragment antigen-binding domains (Fabs) from anti-Frizzled and anti-LRP6 monoclonal antibodies were conjugated using SpyTag-SpyCatcher chemistry via a one-pot reaction. The resulting synthetic heterodimeric agonist outperformed the natural ligand, Wnt-3a, in activating canonical Wnt signaling in mammalian cells. This approach should be broadly applicable to activate receptor-mediated cellular signaling.


Assuntos
Anticorpos Monoclonais/farmacologia , Proteína Wnt3A/agonistas , Anticorpos Monoclonais/química , Dimerização , Humanos , Ligantes , Estrutura Molecular , Via de Sinalização Wnt/efeitos dos fármacos
9.
Ground Water ; 57(1): 21-35, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30407623

RESUMO

The interaction between surface water and groundwater during flood events is a complex process that has traditionally been described using simplified analytical solutions, or abstracted numerical models. To make the problem tractable, it is common to idealize the flood event, simplify river channel geometry, and ignore bank soil heterogeneity, often resulting in a model that only loosely represents the site, thus limiting its applicability to any specific river cross-section. In this study, we calibrate a site-specific fully-integrated surface and subsurface HydroGeoSphere model using flood events for a cross-section along the South River near Waynesboro, VA. The calibration approach presented in this study demonstrates the incorporation of fining direction regularization with a highly parameterized inversion driven by natural stimuli, to develop several realistic realizations of hydraulic conductivity fields that reflect the depositional history of the system. Specifically, we calibrate a model with 365 unique material zones to multiple flood events recorded in a dense well network while incorporating possible fining sequences consistent with the depositional history of the riverbank. Over 25,000 individual simulations were completed using calibration software and a cloud platform specifically designed for highly parallelized computing environments. The results of this study demonstrate the use of fining direction regularization during model calibration to generate multiple calibrated model realizations that account for the depositional environment of the system.


Assuntos
Água Subterrânea , Calibragem , Hidrologia , Modelos Teóricos , Rios , Movimentos da Água
10.
Chem Asian J ; 14(2): 244-255, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30523672

RESUMO

Multivalent interactions in which multiple ligands on one object bind to multiple receptors on another are commonly found in natural biological systems. In addition, these interactions can lead to increased strength and selectivity when compared to the corresponding monovalent interaction. These attributes have also guided the design of synthetic multivalent ligands to control biological interactions. This review will highlight the recent literature describing the use of multivalent ligand display in the design of vaccines, immunomodulators, cell signaling effectors, and vehicles for targeted drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Desenho de Fármacos , Fatores Imunológicos/imunologia , Vacinas/imunologia , Animais , Linhagem Celular Tumoral , Humanos , Fatores Imunológicos/síntese química , Ligantes , Transdução de Sinais/efeitos dos fármacos , Vacinas/síntese química
11.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 8): 1075-1078, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30116565

RESUMO

Structural analysis of (acetato-κ2O,O')(methanol-κO)[tris-(pyridin-2-ylmeth-yl)amine-κ4N,N',N'',N''']manganese(II) tetraphenyl-borate, [Mn(C2H3O2)(C18H18N4)(CH3OH)](C24H20B) or [Mn(TMPA)(Ac)(CH3OH)]BPh4 [TMPA = tris-(pyridin-2-ylmeth-yl)amine, Ac = acetate, BPh4 = tetra-phenyl-borate] by single-crystal X-ray diffraction reveals a complex cation with tetra-dentate coordination of the tripodal TMPA ligand, bidentate coordination of the Ac ligand and monodentate coordination of the methanol ligand to a single MnII center, balanced in charge by the presence of a tetra-phenyl-borate anion. The MnII complex has a distorted penta-gonal-bipyramidal geometry, in which the central amine nitro-gen and two pyridyl N atoms of the TMPA ligand, and two oxygen atoms of the acetate ligand occupy positions in the penta-gonal plane, while the third pyridyl nitro-gen of TMPA and the oxygen from the methanol ligand occupy the axial positions. Within the complex, the acetate O atoms participate in weak C-H⋯O hydrogen-bonding inter-actions with neighboring pyridyl moieties. In the crystal, complexes form dimers by pairs of O-H⋯O hydrogen bonds between the coordinated methanol of one complex and an acetate oxygen of the other, and weak π-stacking inter-actions between pyridine rings. Separate dimers then undergo additional π-stacking inter-actions between the pyridine rings of one moiety and either the pyridine or phenyl rings of another moiety that further stabilize the crystal.

12.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 8): 1138-1141, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30116579

RESUMO

Structural characterization of the compound [Cu(C2H3N)(C23H23N3O)](ClO4)2] or [Cu(C2H3N)(DQMEA)](ClO4)2] [DQMEA = 2-methoxy-N,N-bis-(quinolin-2-ylmeth-yl)ethyl-amine] {systematic name: (aceto-nitrile)[2-methoxy-N,N-bis(quinolin-2-ylmeth-yl)ethyl-amine]-copper(II) diperchlorate} by single-crystal X-ray diffraction reveals a complex cation with a tetra-dentate coordination of the DQMEA ligand along with monodentate coordination of a CH3CN ligand to a single CuII center, with two perchlorate anions providing charge balance. The CuII center has a distorted square-pyramidal geometry in which the nitro-gen atoms of the DQMEA and CH3CN ligands occupy the equatorial positions, while the oxygen atom of the DQMEA ligand resides in the axial position with an elongated Cu-O bond. The quinoline ring systems are nearly co-planar in the structure, while the linear CH3CN ligand is tilted significantly below this plane, and the central nitro-gen of DQMEA is above it. Within the complex, weak C-H⋯N hydrogen bonding takes place between the nitro-gen of CH3CN and a neighboring quinolyl group. The perchlorate ions are disordered within the structure, but undergo a number of weak inter-molecular C-H⋯O hydrogen-bonding inter-actions. Additional weak π-stacking inter-actions between the quinolyl groups of neighboring complexes further stabilize the crystal packing.

13.
Sci Total Environ ; 624: 1586-1597, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29929267

RESUMO

This study compared the impact of controlled tile drainage (CD) and freely draining (FD) systems on the prevalence and quantitative real-time PCR-based enumeration of four major pathogens including Arcobacter butzleri, Campylobacter jejuni, Campylobacter coli, and Helicobacter pylori in tile- and groundwater following a fall liquid swine manure (LSM) application on clay loam field plots. Although the prevalence of all target pathogens were detected in CD and FD systems, the loads of A. butzleri, C. jejuni, and C. coli were significantly lower in CD tile-water (p<0.05), in relation to FD tile-water. However, concentrations of A. butzleri were significantly greater in CD than FD tile-water (p<0.05). In shallow groundwater (1.2m depth), concentrations of A. butzleri, C. coli, and H. pylori showed no significant difference between CD and FD plots, while C. jejuni concentrations were significantly higher in FD plots (p<0.05). No impact of CD on the H. pylori was observed since quantitative detection in tile- and groundwater was scarce. Although speculative, H. pylori occurrence may have been related to the application of municipal biosolids four years prior to the LSM experiment. Overall, CD can be used to help minimize off-field export of pathogens into surface waters following manure applications to land, thereby reducing waterborne pathogen exposure risks to humans.


Assuntos
Água Subterrânea/microbiologia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Microbiologia da Água , Agricultura/métodos , Reação em Cadeia da Polimerase em Tempo Real
14.
Curr Opin Biotechnol ; 52: 80-88, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29597075

RESUMO

There have been significant advances in the design of nanostructured scaffolds for eliciting robust immune responses. One method to produce strong immune responses is to emulate the appearance of a pathogen. Since pathogens such as viruses and bacteria often display multiple copies of ligands on their surfaces, the immune system is particularly sensitive towards multivalent displays of antigens. Consequently, when designing a vaccine, it is advantageous to decorate a nanostructured surface with multiple copies of an antigen. This review highlights the design and efficacy of a diverse set of recently developed nanostructured vaccine scaffolds.


Assuntos
Biotecnologia/métodos , Nanotecnologia/métodos , Vacinas/imunologia , Animais , Antígenos/imunologia , Nanoestruturas/química , Vírion/metabolismo
15.
Sci Total Environ ; 532: 138-53, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26065824

RESUMO

This work investigated chlortetracycline, tylosin, and tetracycline (plus transformation products), and DNA-based quantitative Campylobacter spp. and Campylobacter tetracycline antibiotic resistant genes (tet(O)) in tile drainage, groundwater, and soil before and following a liquid swine manure (LSM) application on clay loam plots under controlled (CD) and free (FD) tile drainage. Chlortetracycline/tetracycline was strongly bound to manure solids while tylosin dominated in the liquid portion of manure. The chlortetracycline transformation product isochlortetracycline was the most persistent analyte in water. Rhodamine WT (RWT) tracer was mixed with manure and monitored in tile and groundwater. RWT and veterinary antibiotic (VA) concentrations were strongly correlated in water which supported the use of RWT as a surrogate tracer. While CD reduced tile discharge and eliminated application-induced VA movement (via tile) to surface water, total VA mass loading to surface water was not affected by CD. At both CD and FD test plots, the biggest 'flush' of VA mass and highest VA concentrations occurred in response to precipitation received 2d after application, which strongly influenced the flow abatement capacity of CD on account of highly elevated water levels in field initiating overflow drainage for CD systems (when water level <0.3m below surface). VA concentrations in tile and groundwater became very low within 10d following application. Both Campylobacter spp. and Campylobacter tet(O) genes were present in groundwater and soil prior to application, and increased thereafter. Unlike the VA compounds, Campylobacter spp. and Campylobacter tet(O) gene loadings in tile drainage were reduced by CD, in relation to FD.


Assuntos
Antibacterianos/análise , Drenagem Sanitária/métodos , Resistência Microbiana a Medicamentos/genética , Água Subterrânea/microbiologia , Agricultura/métodos , Animais , Campylobacter , Monitoramento Ambiental , Água Subterrânea/química , Esterco , Eliminação de Resíduos Líquidos/métodos , Microbiologia da Água , Poluentes da Água/análise
16.
Water Res ; 47(16): 6326-37, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24079968

RESUMO

Developing the capability to predict pathogens in surface water is important for reducing the risk that such organisms pose to human health. In this study, three primary data source scenarios (measured stream flow and water quality, modelled stream flow and water quality, and host-associated Bacteroidales) are investigated within a Classification and Regression Tree Analysis (CART) framework for classifying pathogen (Escherichia coli 0157:H7, Salmonella, Campylobacter, Cryptosporidium, and Giardia) presence and absence (P/A) for a 178 km(2) agricultural watershed. To provide modelled data, a Soil Water Assessment Tool (SWAT) model was developed to predict stream flow, total suspended solids (TSS), total N and total P, and fecal indicator bacteria loads; however, the model was only successful for flow and total N and total P simulations, and did not accurately simulate TSS and indicator bacteria transport. Also, the SWAT model was not sensitive to an observed reduction in the cattle population within the watershed that may have resulted in significant reduction in E. coli concentrations and Salmonella detections. Results show that when combined with air temperature and precipitation, SWAT modelled stream flow and total P concentrations were useful for classifying pathogen P/A using CART methodology. From a suite of host-associated Bacteroidales markers used as independent variables in CART analysis, the ruminant marker was found to be the best initial classifier of pathogen P/A. Of the measured sources of independent variables, air temperature, precipitation, stream flow, and total P were found to be the most important variables for classifying pathogen P/A. Results indicate a close relationship between cattle pollution and pathogen occurrence in this watershed, and an especially strong link between the cattle population and Salmonella detections.


Assuntos
Bactérias/isolamento & purificação , Monitoramento Ambiental , Modelos Teóricos , Microbiologia da Água , Agricultura , Fezes/microbiologia , Água Doce/microbiologia , Água Doce/parasitologia , Abastecimento de Água/normas
17.
J Environ Qual ; 42(3): 881-92, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673956

RESUMO

This study investigated the potential for controlled tile drainage (CD) to reduce bacteria and nutrient loading to surface water and groundwater from fall-season liquid manure application (LMA) on four macroporous clay loam plots, of which two had CD and two had free-draining (FD) tiles. Rhodamine WT (RWT) was mixed into the manure and monitored in the tile water and groundwater following LMA. Tile water and groundwater quality were influenced by drainage management. Following LMA on the FD plots, RWT, nutrients, and bacteria moved rapidly via tiles to surface water; at the CD plots, tiles did not flow until the first post-LMA rainfall, so the immediate risk of LMA-induced contamination of surface water was abated. During the 36-d monitoring period, flow-weighted average specific conductance, redox potential, and turbidity, as well as total Kjeldahl N (TKN), total P (TP), NH-N, reactive P, and RWT concentrations, were higher in the CD tile effluent; however, because of lower tile discharge from the CD plots, there was no significant ( ≤ 0.05) difference in surface water nutrient and RWT loading between the CD and FD plots when all tiles were flowing. The TKN, TP, and RWT concentrations in groundwater also tended to be higher at the CD plots. Bacteria behaved differently than nutrients and RWT, with no significant difference in total coliform, , fecal coliform, fecal streptococcus, and concentrations between the CD and FD tile effluent; however, for all but , hourly loading was higher from the FD plots. Results indicate that CD has potential for mitigating bacteria movement to surface water.


Assuntos
Esterco , Água , Agricultura , Drenagem , Monitoramento Ambiental , Água Subterrânea , Esterco/microbiologia , Movimentos da Água
18.
ACS Appl Mater Interfaces ; 2(10): 2828-32, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20825230

RESUMO

A novel biomaterial formed by the immobilization of the Aminopeptidase from Aeromonas proteolytica (AAP) on synthetic Mg2+ and Al3+ ion-containing layered double hydroxide (LDH) particles was prepared. Immobilization of AAP on the LDH particles in a buffered, aqueous mixture is rapid such that the maximum loading capacity, 1×10(-9) moles of AAP/mg LDH, is achieved in a few minutes. X-ray powder diffraction of LDH samples before and after treatment with AAP indicates that the enzyme does not intercalate between the layers of LDH, but instead binds to the surface. Treatment of AAP/LDH with various amounts of salt in a buffered mixture demonstrates that between 15 and 20% of AAP can be removed from the LDH by washing the composite material in 0.2 M NaCl. However, the residual AAP remains bound to the LDH even at 1 M salt concentrations. A suspension of the AAP/LDH biomaterial in 10 mM Tricine buffered, aqueous solution (pH 8.0 and 25° C) catalyzes the hydrolysis of l-leucine-p-nitroanilide demonstrating that immobilized AAP remains available to substrate and retains its catalytic activity. Recycling experiments reveal that the AAP/LDH particles can be recovered and reused multiple times without appreciable loss of activity. This work provides the foundation for the development of materials that will function in the degradation or detection of peptide hormones or neurotoxins.


Assuntos
Aeromonas/enzimologia , Óxido de Alumínio/química , Aminopeptidases/química , Proteínas de Bactérias/química , Enzimas Imobilizadas/química , Óxido de Magnésio/química , Neurotoxinas/química , Hormônios Peptídicos/química
19.
Science ; 326(5950): 285-9, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19729618

RESUMO

Broadly neutralizing antibodies (bNAbs), which develop over time in some HIV-1-infected individuals, define critical epitopes for HIV vaccine design. Using a systematic approach, we have examined neutralization breadth in the sera of about 1800 HIV-1-infected individuals, primarily infected with non-clade B viruses, and have selected donors for monoclonal antibody (mAb) generation. We then used a high-throughput neutralization screen of antibody-containing culture supernatants from about 30,000 activated memory B cells from a clade A-infected African donor to isolate two potent mAbs that target a broadly neutralizing epitope. This epitope is preferentially expressed on trimeric Envelope protein and spans conserved regions of variable loops of the gp120 subunit. The results provide a framework for the design of new vaccine candidates for the elicitation of bNAb responses.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , África Subsaariana , Subpopulações de Linfócitos B/imunologia , Epitopos/imunologia , Anticorpos Anti-HIV/biossíntese , Proteína gp120 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/imunologia , Humanos , Memória Imunológica , Ativação Linfocitária , Testes de Neutralização , Fragmentos de Peptídeos/imunologia , Multimerização Proteica , Proteínas Recombinantes/imunologia
20.
J Knee Surg ; 21(1): 55-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18300673

RESUMO

We present an unusual case of an athletic 17-year-old male cyclist with bilateral chronic dislocating biceps femoris tendons. On flexion of the knee, the biceps tendon subluxed over a large exostosis, creating a snapping sound. Snapping of tendons is common around the hip, ankles, shoulder, and elbow, but rare at the knee. When it does occur, snapping about the knee can be due to discoid meniscus, rheumatoid nodules, synovial plicae, iliotibial band syndrome, congenital snapping knee, and snapping tendons. Research revealed only 5 previous cases due to subluxation of the biceps femoris tendon. The case we present is the only one due to an exostosis, as well as the only one that required bilateral surgical repair. The patient presented when his pain became significant enough to interfere with his ability to continue competitive cycling.


Assuntos
Exostose/complicações , Fíbula/diagnóstico por imagem , Traumatismos dos Tendões/etiologia , Adolescente , Exostose/diagnóstico por imagem , Exostose/cirurgia , Humanos , Radiografia , Traumatismos dos Tendões/cirurgia
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