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1.
mBio ; 15(3): e0325223, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38289074

RESUMEN

Pericytes are located around blood vessels, in close contact with endothelial cells. We discovered that pericytes dampen pro-inflammatory endothelial cell responses. Endothelial cells co-cultured with pericytes had markedly reduced expression of adhesion molecules (PECAM-1 and ICAM-1) and proinflammatory cytokines (CCL-2 and IL-6) in response to bacterial stimuli (Brucella ovis, Listeria monocytogenes, or Escherichia coli lipopolysaccharide). Pericyte-depleted mice intraperitoneally inoculated with either B. ovis, a stealthy pathogen that does not trigger detectable inflammation, or Listeria monocytogenes, developed peritonitis. Further, during Citrobacter rodentium infection, pericyte-depleted mice developed severe intestinal inflammation, which was not evident in control mice. The anti-inflammatory effect of pericytes required connexin 43, as either chemical inhibition or silencing of connexin 43 abrogated pericyte-mediated suppression of endothelial inflammatory responses. Our results define a mechanism by which pericytes modulate inflammation during infection, which shifts our understanding of pericyte biology: from a structural cell to a pro-active player in modulating inflammation. IMPORTANCE: A previously unknown mechanism by which pericytes modulate inflammation was discovered. The absence of pericytes or blocking interaction between pericytes and endothelium through connexin 43 results in stronger inflammation, which shifts our understanding of pericyte biology, from a structural cell to a player in controlling inflammation.


Asunto(s)
Infecciones Bacterianas , Pericitos , Animales , Ratones , Ovinos , Pericitos/metabolismo , Células Endoteliales , Conexina 43/metabolismo , Conexina 43/farmacología , Inflamación , Infecciones Bacterianas/metabolismo
2.
Water Res ; 211: 118071, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35063927

RESUMEN

Metaldehyde is a polar, mobile, low molecular weight pesticide that is challenging to remove from drinking water with current adsorption-based micropollutant treatment technologies. Alternative strategies to remove this and compounds with similar properties are necessary to ensure an adequate supply of safe and regulation-compliant drinking water. Biological removal of metaldehyde below the 0.1 µg•L-1 regulatory concentration was attained in pilot-scale slow sand filters (SSFs) subject to bioaugmentation with metaldehyde-degrading bacteria. To achieve this, a library of degraders was first screened in bench-scale assays for removal at micropollutant concentrations in progressively more challenging conditions, including a mixed microbial community with multiple carbon sources. The best performing strains, A. calcoaceticus E1 and Sphingobium CMET-H, showed removal rates of 0.0012 µg•h-1•107 cells-1 and 0.019 µg•h-1•107 cells-1 at this scale. These candidates were then used as inocula for bioaugmentation of pilot-scale SSFs. Here, removal of metaldehyde by A. calcoaceticus E1, was insufficient to achieve compliant water regardless testing increasing cell concentrations. Quantification of metaldehyde-degrading genes indicated that aggregation and inadequate distribution of the inoculum in the filters were the likely causes of this outcome. Conversely, bioaugmentation with Sphingobium CMET-H enabled sufficient metaldehyde removal to achieve compliance, with undetectable levels in treated water for at least 14 d (volumetric removal: 0.57 µg•L-1•h-1). Bioaugmentation did not affect the background SSF microbial community, and filter function was maintained throughout the trial. Here it has been shown for the first time that bioaugmentation is an efficient strategy to remove the adsorption-resistant pesticide metaldehyde from a real water matrix in upscaled systems. Swift contaminant removal after inoculum addition and persistent activity are two remarkable attributes of this approach that would allow it to effectively manage peaks in metaldehyde concentrations (due to precipitation or increased application) in incoming raw water by matching them with high enough degrading populations. This study provides an example of how stepwise screening of a diverse collection of degraders can lead to successful bioaugmentation and can be used as a template for other problematic adsorption-resistant compounds in drinking water purification.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Acetaldehído/análogos & derivados , Filtración , Contaminantes Químicos del Agua/análisis
3.
J Bodyw Mov Ther ; 28: 187-192, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34776140

RESUMEN

INTRODUCTION: An arteriovenous fistula (AVF) is performed in chronic kidney disease (CKD) patients before hemodialysis, who may benefit from exercise. The aim of this study was to evaluate the effect of an exercise program associated with partial limb blood flow restriction (BFR) on handgrip strength (HGS) and forearm circumference of CKD patients. METHODS: A total of 26 patients with CKD were randomized to the BFR experimental group (EG, n = 12) and to the non-BFR control group (CG, n = 14) prior to AVF, and underwent isometric exercises for the flexor muscles of the fingers and elbow where the AVF will be performed. RESULTS: There were no differences at the end of eight weeks of training between the EG and CG groups [F (1.23) = 0.03, p = 0.96] regarding the HGS and the forearm circumference [F (1.23) = 0.90, p = 0.76], however muscle strength [F (1.23) = 189.84, p < 0.001] and forearm circumference [F (1.23) = 540.90, p < 0.001] improved between baseline and the results at the end of the program. CONCLUSION: Partial BFR training was not superior to the CG for the outcomes evaluated in this study. Further studies should be conducted so that an indication of an exercise protocol for the evaluated outcomes is prescribed in order to be effectively offered in clinical practice.


Asunto(s)
Insuficiencia Renal Crónica , Entrenamiento de Fuerza , Ejercicio Físico , Terapia por Ejercicio , Fuerza de la Mano , Humanos , Fuerza Muscular , Músculo Esquelético , Flujo Sanguíneo Regional , Insuficiencia Renal Crónica/terapia
4.
Water Res ; 206: 117779, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34717244

RESUMEN

Ammonia ion removal and recovery via an ion-exchange process using zeolites is a promising alternative to traditional biological treatments. The analysis of its efficiency is not straightforward as it depends on various factors, such as the cation exchange capacity of the zeolite, amount of zeolite available, initial ammonia concentration, contact time, ammonia speciation depending on pH or the presence of competing ions. Mathematical modelling and simulation tools are very useful to analyse the effect of different operational conditions on the efficiency and optimal operation of the process. This paper experimentally analyses the effect that the presence of competing ions has on the efficiency of ammonia removal. This experimental work has shown a reduction of around 21% of ammonia removal efficiency in the presence of competing ions. The main contribution of this paper is the development new mathematical model able to describe the ion-exchange process in the presence of competing ions. The mathematical model developed is able to analyse the performance of the IEX process under different empty bed contact times, influent loads, pH and concentrations of competing ions. The capability of the model to reproduce real data has been proven comparing the experimental and simulation results. Finally, an exploration by simulation has been undertaken to show the potential of the mathematical model developed.


Asunto(s)
Amoníaco , Zeolitas , Adsorción , Calibración , Intercambio Iónico , Iones , Modelos Teóricos
5.
Environ Technol ; : 1-14, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34057403

RESUMEN

Anaerobic ponds have the potential to contribute to low carbon wastewater treatment, however are currently restricted by long hydraulic residence time (HRT) which leads to large land requirements. A two-stage anaerobic pond (SAP) design was trialled against a single-stage control (CAP) over four HRTs down to 0.5 days, to determine the lowest HRT at which the ponds could operate effectively. No statistical differences were observed in particulate removal between the ponds over all four HRTs, suggesting solids loading is not a critical factor in AP design. Significantly higher biogas production rates were observed in the SAP than the CAP at 1.5 d and 1.0 d HRT, and microbial community profiling suggests the two-stage design may be facilitating spatial separation of the anaerobic digestion process along reactor length. Hydrogenotrophic methanogensis dominated over aceticlastic, with acetate oxidisation a likely degradation pathway. Experimental tracer studies were compared to CFD simulations, with the SAP showing greater hydraulic efficiency, and differences more pronounced at shorter HRTs. Greater flow recirculation between baffles was observed in CFD velocity profiles, demonstrating baffles can dissipate preferential flow patterns and increase effective pond volume, especially at high flow rates. The study demonstrates the potential of APs to be operated at shorter HRTs in psychrophilic conditions, presenting an opportunity for use as pre-treatments (in place of septic tanks) and primary treatment for full wastewater flows. Two-stage designs should be investigated to separate the stages of the anaerobic digestion process by creating preferential conditions along the pond length.

6.
Arch Virol ; 166(5): 1447-1453, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33687538

RESUMEN

Challenging wild plant accessions with pathogens is an initial approach for finding resistance genes for breeding programs. Viruses can be transmitted artificially by mechanical or arthropod-borne inoculation, but these experimental assays do not always reproduce natural conditions in the field. In this study, 56 wild Capsicum spp. accessions from Ecuador that were under natural inoculum pressure for six months were screened for virus infections by RNA sequencing. These plants exhibited low virus diversity in comparison to a commercial pepper cultivar that was used as a susceptible host. Subjecting numerous plants to natural infection prior to artificial assays may indicate promising accessions to track within virus/vector resistance breeding programs.


Asunto(s)
Capsicum/virología , Enfermedades de las Plantas/virología , Biodiversidad , Capsicum/clasificación , Capsicum/genética , Resistencia a la Enfermedad/genética , Ecuador , Fitomejoramiento , ARN Viral/genética , Virus/clasificación , Virus/genética , Virus/aislamiento & purificación
7.
J Gen Virol ; 102(2)2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33210991

RESUMEN

Tobamoviruses are often referred to as the most notorious viral pathogens of pepper crops. These viruses are not transmitted by invertebrate vectors, but rather by physical contact and seeds. In this study, pepper plants displaying mild mottle and mosaic symptoms were sampled in four different regions of Peru. Upon double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) tests, seven samples cross-reacted weakly with antibodies against pepper mild mottle virus (PMMoV), suggesting the presence of tobamoviruses. When employing RT-PCR, conserved primers amplified cDNA fragments of viruses from two putative new tobamovirus species in the samples. The complete genome of two representative isolates were, therefore, sequenced and analysed in silico. These viruses, which were tentatively named yellow pepper mild mottle virus (YPMMoV) and chilli pepper mild mottle virus (CPMMoV), shared highest nucleotide genome sequence identities of 83 and 85 % with bell pepper mottle virus (BpeMV), respectively. Mechanical inoculation of indicator plants with YPMMoV and CPMMoV isolates did not show any obvious differences in host ranges. These viruses were also inoculated mechanically on pepper plants harbouring different resistance L alleles to determine their pathotypes. Pepper plants carrying unfunctional L alleles (L0) to tobamoviruses were infected by all isolates and presented differential symptomatology for YPMMoV and CPMMoV. On the other hand, pepper plants carrying L1, L2, L3 and L4 alleles were resistant to all isolates, indicating that these viruses belong to pathotype P0.


Asunto(s)
Enfermedades de las Plantas/virología , Tobamovirus/clasificación , Tobamovirus/genética , Secuencia de Bases , Capsicum/virología , Cartilla de ADN/genética , ADN Viral/genética , Genoma Viral , Especificidad del Huésped
8.
J Environ Manage ; 267: 110647, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32421677

RESUMEN

Commercial kitchen wastewaters are typically strong organic and fat-rich effluents, often identified as major contributors to fatberg formation and associated blockages in sewers. Experimental trials were done using synthetic kitchen wastewater to understand the complex reactions involved in microbial remediation in grease traps/separators prior discharge in sewers. The principle organic components (FOG, carbohydrate and protein nitrogen), were varied using ranges observed in a previous study on real kitchen wastewater characterisation. A model bacterium, Bacillus licheniformis NCIMB 9375, was used to evaluate microbial utilisation of the different organic fractions in relation to fat, oil and grease (FOG) degradation. Novel results in the treatment of these effluents showed that, the presence and concentration of alternative carbon sources and the ratio of carbon to nitrogen (COD:N) had great influence on FOG-degradation response. For example, FOG removal decreased from 24 to 10 mg/l/h when glucose was substitute for starch at equivalent concentrations (500 mg/l); and from 26 to 5 mg/l/h when initial COD:N increased from 45:1 to 147:1. The dominant influence of COD:N was validated using a commercial bioadditive and real kitchen wastewater adjusted to different COD:N ratios, confirming the strong influence of kitchen wastewater composition on bioremediation outcomes. These results can therefore have major implications for biological management of FOG in kitchens and sewers as they provide a scientific explanation for bioremediation success or failure.


Asunto(s)
Aceites , Aguas Residuales , Biodegradación Ambiental , Hidrocarburos
9.
Water Res ; 176: 115754, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32247993

RESUMEN

In this study, the mechanisms for solids breakthrough in upflow anaerobic sludge blanket (UASB) configured anaerobic membrane bioreactors (AnMBRs) have been described to establish design parameters to limit membrane fouling. As the sludge blanket develops, two periods can be identified: (i) an initial progressive enhancement in solids separation provided through sludge blanket clarification, via depth filtration, which sustains downstream membrane permeability; and (ii) sludge blanket destabilisation, which imposed solids breakthrough resulting in a loss in membrane permeability. The onset of sludge blanket destabilisation was identified earlier in the flocculent AnMBR, which was ascribed to an increased gas production, caused by hydrolysis within the sludge blanket at extended solids residence time. Whilst hydrolysis also induced higher gas productivity within the granular AnMBR, solids breakthrough was not evidently observed during this period, and was instead only observed as the sludge blanket approached the UASB overflow. However, solids breakthrough was observed earlier for both reactors when treating wastewater with lower temperatures. This was explained through characterisation of the settling velocity of discrete particles from the sludge blanket of both MBRs; solids washout was evidenced to be induced by the increase in fluid viscosity with a reduction in temperature, which lowered terminal particle settling velocity. Nevertheless, particle settling velocity was comparable for particles from both sludge blankets. We therefore propose that the enhanced stability imparted by the granular AnMBR is due to the higher inertial force of the dense granular sludge. From this study, we suggest that similarly low levels of membrane fouling can be achieved within flocculent AnMBR by managing solids retention time to constrain sludge bed height and excess hydrolysis, together with adopting an upflow velocity based on particle buoyancy at the lowest expected operating temperature.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Anaerobiosis , Filtración , Eliminación de Residuos Líquidos , Aguas Residuales
10.
Water Res ; 174: 115613, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32092546

RESUMEN

Operational and financial constraints challenge effective removal of natural organic matter (NOM), and specifically disinfection by-product (DBP) precursors, at remote and/or small sites. Granular activated carbon (GAC) is a widely used treatment option for such locations, due to its relatively low maintenance and process operational simplicity. However, its efficacy is highly dependent on the media capacity for the organic matter, which in turn depends on the media characteristics. The influence of GAC media properties on NOM/DBP precursor removal has been studied using a range of established and emerging media using both batch adsorption tests and rapid small-scale column tests. DBP formation propensity (DBPFP) was measured with reference to trihalomethanes (THMs) and haloacetic acids (HAAs). All GAC media showed no selectivity for specific removal of precursors of regulated DBPs; DBP formation was a simple function of residual dissolved organic carbon (DOC) levels. UV254 was found to be a good surrogate measurement of DBPFP for an untreated water source having a high DOC. Due to the much-reduced concentration of DBP precursors, the correlation was significantly poorer for the coagulation/flocculation-pretreateed water source. Breakthrough curves generated from the microcolumn trials revealed DOC removal and consequent DBP reduction to correlate reasonably well with the prevalence pores in the 5-10 nm range. A 3-6 fold increase in capacity was recorded for a 0.005-0.045 cm3/g change in 5-10 nm-sized pore volume density. No corresponding correlation was evident with other media pore size ranges.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico , Desinfección , Trihalometanos
11.
Environ Sci Process Impacts ; 22(4): 956-972, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32043103

RESUMEN

Pesticide losses from agricultural land to water can result in the environmental deterioration of receiving systems. Mathematical models can make important contributions to risk assessments and catchment management. However, some mechanistic models have high parameter requirements which can make them difficult to apply in data poor areas. In addition, uncertainties in pesticide properties and applications are difficult to account for using models with long run-times. Alternative, simpler, conceptual models are easier to apply and can still be used as a framework for process interpretation. Here, we present a new conceptual model of pesticide behaviour in surface water catchments, based on continuous water balance calculations. Pesticide losses to surface waters are calculated based on the displacement of a limited fraction of the soil pore water during storm events occurring after application. The model was used to describe the behaviour of metaldehyde in a small (2.2 km2) under-drained catchment in Eastern England. Metaldehyde is a molluscicide which has been regularly detected at high concentrations in many drinking water supply catchments. Measured peak concentrations in stream water (to about 9 µg L-1) occurred in the first few storm events after application in mid-August. In each event, there was a quasi-exponential decrease in concentration during hydrograph recession. Peak concentrations decreased in successive events - responding to rainfall but reflecting an effective exhaustion in soil supply due to degradation and dissipation. Uncertain pesticide applications to the catchment were estimated using land cover analysis of satellite data, combined with a Poisson distribution to describe the timing of application. Model performance for both the hydrograph (after calibration of the water balance) and the chemograph was good and could be improved via some minor adjustments in assumptions which yield general insights into the drivers for pesticide transport. The use of remote sensing offers some promising opportunities for estimating catchment-scale pesticide applications and associated losses.


Asunto(s)
Agricultura , Plaguicidas , Contaminantes Químicos del Agua , Acetaldehído/análogos & derivados , Inglaterra , Monitoreo del Ambiente , Modelos Teóricos , Movimientos del Agua
12.
Chemosphere ; 238: 124633, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31454747

RESUMEN

Three different source waters were investigated using virgin and pre-used anion exchange resins, coagulation, and ion exchange combined with coagulation (IEX&Coagulation). The hydrophobicity, size distribution and charge of natural organic matter (NOM) were used to evaluate its removal. Dissolved organic carbon (DOC) removal by pre-used IEX resin was 67-79%. A consistent ratio of different hydrophobicity fractions was found in the removed DOC, while the proportion and quantity of the molecular weight fraction around 1 kDa was important in understanding the treatability of water. For pre-used resin, organic compounds were hypothesised to be restricted to easily accessible exchange sites. Comparatively, virgin resin achieved higher DOC removals (86-89%) as resin fouling was absent. Charge density and the proportion of the hydrophobic fraction were found to be important indicators for the specific disinfection byproduct formation potential (DBP-FP). Treatment of raw water with pre-used resin decreased the specific DBP-FP by between 2 and 43%, while the use of virgin resin resulted in a reduction of between 31 and 63%. The highest water quality was achieved when the combination of IEX and coagulation was used, reducing DOC and the specific DBP-FP well below that seen for either process alone.


Asunto(s)
Compuestos Orgánicos/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Resinas de Intercambio Aniónico/química , Floculación , Interacciones Hidrofóbicas e Hidrofílicas , Intercambio Iónico
13.
Environ Int ; 135: 105354, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31864025

RESUMEN

Ammonia oxidising microorganisms (AOM) play an important role in ammonia removal in wastewater treatment works (WWTW) including rotating biological contactors (RBCs). Environmental factors within RBCs are known to impact the performance of key AOM, such that only some operational RBCs have shown ability for elevated ammonia removal. In this work, long-term treatment performance of seven full-scale RBC systems along with the structure and abundance of the ammonia oxidising bacteria (AOB) and archaea (AOA) communities within microbial biofilms were examined. Long term data showed the dominance of AOB in most RBCs, although two RBCs had demonstrable shift toward an AOA dominated AOM community. Next Generation Sequencing of the 16S rRNA gene revealed diverse evolutionary ancestry of AOB from RBC biofilms while nitrite-oxidising bacteria (NOBs) were similar to reference databases. AOA were more abundant in the biofilms subject to lower organic loading and higher oxygen concentration found at the distal end of RBC systems. Modelling revealed a distinct nitrogen cycling community present within high performing RBCs, linked to efficient control of RBC process variables (retention time, organic loading and oxygen concentration). We present a novel template for enhancing the resilience of RBC systems through microbial community analysis which can guide future strategies for more effective ammonia removal. To best of the author's knowledge, this is the first comparative study reporting the use of next generation sequencing data on microbial biofilms from RBCs to inform effluent quality of small WWTW.


Asunto(s)
Nitrificación , Amoníaco , Archaea , Nitrógeno , Oxidación-Reducción , ARN Ribosómico 16S , Microbiología del Suelo
14.
J Environ Manage ; 252: 109657, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31604184

RESUMEN

Essential for the selection of a reliable treatment system is the characterisation of the effluent to treat. Kitchen wastewater (KWW) from food service establishments (FSEs) is a strong organic and fat-rich effluent whose characterisation has not been sufficiently addressed. KWW composition is highly variable and linked to the FSE's size, the type of meals prepared and the amount of water used during the cleaning. COD, TSS and fat content (FOG) are the most common parameters found in literature. However, other physical and chemical parameters (e.g. temperature, pH, oil droplets characteristics and trace elements), correlated to commercial kitchen cleaning practices rather than the specific effluent, but equally influential on the treatment efficiencies of both physical and biological methods, have hardly been investigated. A comprehensive characterisation of wastewaters from three food service establishments was used to generate data to support the selection of appropriate FOG mitigation methods. Two novel analytical methods were used to quantify the proportion of emulsified FOG and associated droplet size from different kitchen washing effluents. The results showed that more than 90% of the FOG from the dishwasher effluent and around 35% of sink one was emulsified, with droplet sizes less than 100 µm, well below the removal capabilities of conventional grease interceptors, but easily removed using biological means. From the WW composition results, a formula for predictive modelling was derived to represent average organic matter composition for kitchen wastewater as C20H38O10N, applicable in remediation processes. These results offer a good starting point for the design, operation, and optimisation of wastewater treatment systems of oil-rich KWW.


Asunto(s)
Servicios de Alimentación , Aguas Residuales , Hidrocarburos , Temperatura , Eliminación de Residuos Líquidos , Agua
15.
Sci Total Environ ; 691: 1137-1143, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31466195

RESUMEN

Sludge accumulation on the first stage of French design vertical flow constructed wetlands has been reported to improve treatment performance by favouring even sewage distribution on the beds' surface and increasing water retention time. However, due to its relatively low permeability, sludge layer can restrict the hydraulic capacity of the wetlands, requiring careful consideration of the feeding and resting strategy in order to avoid system ponding. This study aimed to elucidate the impact that sludge layer properties have on its permeability and investigate artificial modifications that could enhance it. A positive impact of increased organic matter content on sludge permeability was observed, with a 3-times permeability increase for a 15 percentage points higher volatile solids content. The opposite effect was observed for total solids, where an increase of 19 percentage points led to a drop of 1.6 × 10-16 m2 on permeability. The impact of different surface modifications on drying kinetics and sludge layer properties was studied as a means to accelerate sludge layer mineralisation. Artificial modifications that modify surface tension of the sludge layer have been proved to achieve greater permeability and faster mineralisation of the sludge, with potential to achieve higher hydraulic acceptance and reduced operational costs (lower sludge accumulation) if implemented in full scale vertical flow constructed wetlands.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Humedales , Filtración , Aguas del Alcantarillado
16.
Orthop J Sports Med ; 6(10): 2325967118804204, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30377622

RESUMEN

BACKGROUND: Suture button fixation of syndesmotic injury is growing in popularity, as it has been shown to provide adequate stability in a more cost-effective manner than screw fixation while allowing more physiologic distal tibiofibular joint motion. However, the optimal repair technique and implant orientation have yet to be determined. PURPOSE/HYPOTHESIS: The purpose of this study was to biomechanically compare 3 suture button construct configurations/orientations for syndesmosis fixation: single, parallel, and divergent. The authors hypothesized that all 3 methods would provide adequate stabilization but that the divergent technique would be the most stable. STUDY DESIGN: Controlled laboratory study. METHODS: The fixation strengths of 3 stabilization techniques with suture button devices were compared with 10 cadaveric legs each (N = 30). Ankle motion under cyclic loading was measured in multiple planes: first in the intact state, then following simulated syndesmosis injury, and then following fixation with 1 of 3 randomly assigned constructs-1 suture button, 2 suture buttons in parallel, and 2 divergent suture buttons. Finally, axial loading with external rotation was applied to failure. RESULTS: All syndesmotic fixation methods provided stability to the torn state. There was no statistically significant difference among the 3 fixation techniques in biomechanical stability. Failure most commonly occurred through fibular fracture at supraphysiologic loads. CONCLUSION: Suture button implant fixation for syndesmotic injury appears to provide stability to the torn syndesmosis, and the configuration of the fixation does not appear to affect the strength or security of the stabilization. CLINICAL RELEVANCE: This study provides further insight into the biomechanics and optimal configuration of suture button fixation of the torn syndesmosis. Based on these results, the addition of a second suture button may not significantly contribute to immediate postoperative stability.

17.
Water Res ; 146: 256-263, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30278380

RESUMEN

Dissolved organic carbon (DOC) removal from a river water source was investigated using ion exchange (IEX), coagulation and membrane filtration. This research linked the variable charge characteristics of the organic compounds present in the source water with removal by IEX and coagulation. The raw water charge density fluctuated considerably (between 5.4 and 10.7 meq mgDOC-1) and controlled removal of the charge loading. Importantly, charge density was not correlated with the organic carbon concentration. The combined IEX and coagulation process reduced the specific DBP-FP (sDBP-FP) of the final water, with values as low as 18 µg mgDOC-1 for both haloacetic acids and trihalomethanes. IEX removed a particular fraction of NOM that 1) enhanced coagulation efficiency, providing increased removal of overall DOC; and 2) enabled coagulation to subsequently remove higher levels of specific components of NOM that have a high DBP-FP. The component of NOM removed by IEX that had a positive impact on coagulation was identified to be charged low molecular weight organic compounds of all hydrophobicity levels, resulting in a reduced specific DBP-FP compared to coagulation alone.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Intercambio Iónico , Compuestos Orgánicos , Trihalometanos
18.
Pesqui. vet. bras ; 38(5): 847-851, May 2018. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-955422

RESUMEN

The health monitoring and management systems of coturniculture can be deemed to be in a developmental phase when compared to the poultry industry. Studies regarding taxonomy and parasitic biology in quails (Coturnix japonica) has not been well conducted in Brazil. Most of the information is available from the autopsy case reports, in many ways the parasitic fauna of quails is still unknown. The aim of this study was to conduct a parasitological research in quails in order to contribute to ameliorate this situation. 31 quails, which were 12 months old, were used for the study. Their carcasses and viscera were sent to the Laboratory of Entomology and Tropical Diseases, INPA, Manaus/AM. The circulatory, nervous, respiratory, digestive and reproductive systems of these were studied separately. No blood parasites were found, however, nine species of endoparasites were registered which were distributed among the classes Cestoda, Nematoda and Protozoa. The helminths were distributed in the duodenum, jejunum, ileum, cecum and oviduct. The cecum was found to be the most parasitized organ and contained a wide range of parasites having three species of protozoa and three species of nematodes. Six morphotypes of Eutrichomastix globosus were recorded, and some morphotypes were hyperparasitized with sporangia Sphaerita sp. in the cytoplasm. A large number of parasites were recorded in this study, as well as the protozoan Blastocystis hominis was first being observed for quail.(AU)


A coturnicultura conta com um monitoramento sanitário e sistemas de manejo ainda em desenvolvimento quando comparado à avicultura industrial. Pesquisas de taxonomia e biologia parasitárias em codornas (Coturnix japonica) são pouco realizadas no Brasil, sendo a maioria das informações disponíveis referentes a relatos de caso em achados de necropsia, portanto, em muitos aspectos a fauna parasitária de codornas é ainda desconhecida. Este trabalho teve por objetivo realizar uma pesquisa parasitológica em codornas em fim de postura. Para pesquisa foram disponibilizadas 31 codornas com idades de 12 meses. As carcaças e suas vísceras foram encaminhadas ao Laboratório de Entomologia e Doenças Tropicais INPA, Manaus/AM. Foram estudados separadamente os sistemas circulatórios, nervoso, respiratório, digestivo e reprodutivo. Das 31 codornas examinadas nenhuma apresentou hemoparasitos, contudo, foram registradas nove espécies de endoparasitos distribuídas entre as classes Cestoda, Nematoda e protozoários. Os helmintos distribuíam-se pelo duodeno, jejuno, íleo, cecos e oviduto. O ceco foi o órgão mais parasitado e com maior diversidade de parasitas, sendo três espécies de protozoários e três de nematóides. Foram registrados seis morfotipos de Eutrichomastix globosus, sendo que, alguns morfótipos estavam hiperparasitados com esporângio Sphaerita sp. no citoplasma. Uma grande variedade de parasitos foi registrada nesta pesquisa, bem como, o protozoário Blastocystis hominis pela primeira vez sendo descrito para codornas.(AU)


Asunto(s)
Animales , Blastocystis hominis/patogenicidad , Coturnix/parasitología , Parabasalidea/patogenicidad , Granjas/organización & administración
19.
Proc (Bayl Univ Med Cent) ; 31(4): 462-464, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30948980

RESUMEN

Patients with a malignant large bowel obstruction are often late in seeking medical attention and are usually in poor health by the time a complete blockage is apparent. Emergency surgery in this setting, particularly in a patient with significant comorbidities, often requires the creation of an ostomy and can result in postoperative complications that delay the administration of adjuvant chemotherapy. This recent case at our center illustrates how the use of a colon stent, as a bridge to surgery, can help patients avoid the need for a stoma and reduce surgical complications.

20.
Environ Technol ; 38(2): 154-162, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27855542

RESUMEN

This paper demonstrates that utilising a vertical flow (VF) wetland after a conventional activated sludge (CAS) delivers equivalent or better effluent quality to a membrane bioreactor (MBR) based on a side-by-side pilot trial. The CAS was operated under the solids retention times (SRT) of 6, 12, and 20 days, with the effluent from each pilot plant fed onto a soil aquifer treatment column to better understand their water reuse application potential. Results showed an upgraded CAS + VF system could deliver effluents with median values of 34 mgO2.L-1, 7 mg.L-1 and 1.9 mg.L-1 for organics, solids and ammonia nitrogen, respectively, which were statistically similar to those from the MBR. Water reuse standards were achieved by the upgraded system for most parameters, with the exception of total coliform removal. The upgraded system delivered superior metal removal when compared to the CAS. An economic analysis showed upgrading a CAS with a VF wetland was more favourable than investing in an MBR system for example works of 5000 and 50,000 population equivalents if the VF system was operated at hydraulic loading rates of 0.03 m.d-1 and 0.08 m.d-1, respectively. This was delivered for a tenth of the carbon footprint of the MBR treatment.


Asunto(s)
Reactores Biológicos , Eliminación de Residuos Líquidos/métodos , Humedales , Amoníaco/análisis , Análisis de la Demanda Biológica de Oxígeno , Reactores Biológicos/economía , Cobre/análisis , Costos y Análisis de Costo , Manganeso/análisis , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/economía , Contaminantes del Agua/análisis , Zinc/análisis
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