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1.
Knee Surg Sports Traumatol Arthrosc ; 30(9): 3215-3219, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34251470

RESUMO

PURPOSE: Unicompartmental knee arthroplasty (UKA) provides patients with an alternative treatment to TKA in isolated medial compartment osteoarthritis providing better functional outcomes and faster recovery in the short term. Our aim was to quantify revision rates, predictors of revision, mortality rate and functionality of the Oxford Phase 3 UKA in a non-designer institution. METHODS: This was a retrospective review of prospectively collected regional registry data. All Oxford Phase 3 UKAs performed for medial tibio-femoral osteoarthritis of the knee joint were included from a single academic institution between the period of January 1st 2006 and December 30th 2009. Kaplan-Meier survivorship curves adjusting for loss to follow-up and deceased patients were generated. Primary outcome variables included all-cause and aseptic revision. Secondary outcome variables included functional outcome scores. Patients were reviewed at 6 months, 2 years, 5 years, 10 years and 15 years. RESULTS: A total of 64 cemented Oxford phase 3 UKAs were performed between January 2006 and November 2009. Fifteen-year follow-up data were available for 51 patients, of these 12 required revision. Survival rates, adjusting for patients that were either lost to follow-up or deceased, were 87.5% at 5 years, 81.4% at 10 years and 76.4% at 15 years. The overall aseptic revision rate at the time of review was 18.75% (n = 12). The only significant predictor of postoperative WOMAC score at 15 years was the preoperative WOMAC score (p = 0.03). CONCLUSION: The Oxford Phase 3 UKA for medial tibio-femoral arthritis has promising outcomes at 15-year follow-up with a survival rate of 76.4% in a non-designer centre. LEVEL OF EVIDENCE: III.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Humanos , Articulação do Joelho , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
2.
Chem Rev ; 118(7): 3251-3304, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29465223

RESUMO

Mixed-valent iron [Fe(II)-Fe(III)] minerals such as magnetite and green rust have received a significant amount of attention over recent decades, especially in the environmental sciences. These mineral phases are intrinsic and essential parts of biogeochemical cycling of metals and organic carbon and play an important role regarding the mobility, toxicity, and redox transformation of organic and inorganic pollutants. The formation pathways, mineral properties, and applications of magnetite and green rust are currently active areas of research in geochemistry, environmental mineralogy, geomicrobiology, material sciences, environmental engineering, and environmental remediation. These aspects ultimately dictate the reactivity of magnetite and green rust in the environment, which has important consequences for the application of these mineral phases, for example in remediation strategies. In this review we discuss the properties, occurrence, formation by biotic as well as abiotic pathways, characterization techniques, and environmental applications of magnetite and green rust in the environment. The aim is to present a detailed overview of the key aspects related to these mineral phases which can be used as an important resource for researchers working in a diverse range of fields dealing with mixed-valent iron minerals.

3.
Appl Environ Microbiol ; 83(13)2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28455336

RESUMO

Most described nitrate-reducing Fe(II)-oxidizing bacteria (NRFeOB) are mixotrophic and depend on organic cosubstrates for growth. Encrustation of cells in Fe(III) minerals has been observed for mixotrophic NRFeOB but not for autotrophic phototrophic and microaerophilic Fe(II) oxidizers. So far, little is known about cell-mineral associations in the few existing autotrophic NRFeOB. Here, we investigate whether the designated autotrophic Fe(II)-oxidizing strain (closely related to Gallionella and Sideroxydans) or the heterotrophic nitrate reducers that are present in the autotrophic nitrate-reducing Fe(II)-oxidizing enrichment culture KS form mineral crusts during Fe(II) oxidation under autotrophic and mixotrophic conditions. In the mixed culture, we found no significant encrustation of any of the cells both during autotrophic oxidation of 8 to 10 mM Fe(II) coupled to nitrate reduction and during cultivation under mixotrophic conditions with 8 to 10 mM Fe(II), 5 mM acetate, and 4 mM nitrate, where higher numbers of heterotrophic nitrate reducers were present. Two pure cultures of heterotrophic nitrate reducers (Nocardioides and Rhodanobacter) isolated from culture KS were analyzed under mixotrophic growth conditions. We found green rust formation, no cell encrustation, and only a few mineral particles on some cell surfaces with 5 mM Fe(II) and some encrustation with 10 mM Fe(II). Our findings suggest that enzymatic, autotrophic Fe(II) oxidation coupled to nitrate reduction forms poorly crystalline Fe(III) oxyhydroxides and proceeds without cellular encrustation while indirect Fe(II) oxidation via heterotrophic nitrate-reduction-derived nitrite can lead to green rust as an intermediate mineral and significant cell encrustation. The extent of encrustation caused by indirect Fe(II) oxidation by reactive nitrogen species depends on Fe(II) concentrations and is probably negligible under environmental conditions in most habitats.IMPORTANCE Most described nitrate-reducing Fe(II)-oxidizing bacteria (NRFeOB) are mixotrophic (their growth depends on organic cosubstrates) and can become encrusted in Fe(III) minerals. Encrustation is expected to be harmful and poses a threat to cells if it also occurs under environmentally relevant conditions. Nitrite produced during heterotrophic denitrification reacts with Fe(II) abiotically and is probably the reason for encrustation in mixotrophic NRFeOB. Little is known about cell-mineral associations in autotrophic NRFeOB such as the enrichment culture KS. Here, we show that no encrustation occurs in culture KS under autotrophic and mixotrophic conditions while heterotrophic nitrate-reducing isolates from culture KS become encrusted. These findings support the hypothesis that encrustation in mixotrophic cultures is caused by the abiotic reaction of Fe(II) with nitrite and provide evidence that Fe(II) oxidation in culture KS is enzymatic. Furthermore, we show that the extent of encrustation caused by indirect Fe(II) oxidation by reactive nitrogen species depends on Fe(II) concentrations and is probably negligible in most environmental habitats.


Assuntos
Bactérias/metabolismo , Compostos Ferrosos/metabolismo , Minerais/metabolismo , Nitratos/metabolismo , Acetatos/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Crescimento Quimioautotrófico , Compostos Férricos/metabolismo , Nitritos/metabolismo , Oxirredução
4.
Environ Sci Technol ; 51(9): 4897-4906, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28402123

RESUMO

In this study, we couple iron isotope analysis to microscopic and mineralogical investigation of iron speciation during circumneutral Fe(II) oxidation and Fe(III) precipitation with photosynthetically produced oxygen. In the presence of the cyanobacterium Synechococcus PCC 7002, aqueous Fe(II) (Fe(II)aq) is oxidized and precipitated as amorphous Fe(III) oxyhydroxide minerals (iron precipitates, Feppt), with distinct isotopic fractionation (ε56Fe) values determined from fitting the δ56Fe(II)aq (1.79‰ and 2.15‰) and the δ56Feppt (2.44‰ and 2.98‰) data trends from two replicate experiments. Additional Fe(II) and Fe(III) phases were detected using microscopy and chemical extractions and likely represent Fe(II) and Fe(III) sorbed to minerals and cells. The iron desorbed with sodium acetate (FeNaAc) yielded heavier δ56Fe compositions than Fe(II)aq. Modeling of the fractionation during Fe(III) sorption to cells and Fe(II) sorption to Feppt, combined with equilibration of sorbed iron and with Fe(II)aq using published fractionation factors, is consistent with our resulting δ56FeNaAc. The δ56Feppt data trend is inconsistent with complete equilibrium exchange with Fe(II)aq. Because of this and our detection of microbially excreted organics (e.g., exopolysaccharides) coating Feppt in our microscopic analysis, we suggest that electron and atom exchange is partially suppressed in this system by biologically produced organics. These results indicate that cyanobacteria influence the fate and composition of iron in sunlit environments via their role in Fe(II) oxidation through O2 production, the capacity of their cell surfaces to sorb iron, and the interaction of secreted organics with Fe(III) minerals.


Assuntos
Compostos Ferrosos/química , Synechococcus/metabolismo , Compostos Férricos/química , Ferro/química , Isótopos de Ferro/química , Oxirredução , Oxigênio
5.
J Obstet Gynaecol ; 36(1): 48-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26213806

RESUMO

The art of symphysiotomy for delivery in the instance of cephalopelvic disproportion has been a dying art since the advent of caesarean section but in Ireland this surgical procedure was not abolished until 1992. This practice is still present in the developing world and in some circumstances used in developed countries. This study offers some insights on the 40-year follow-up of patients who had undergone symphysiotomy.


Assuntos
Dor Lombar/etiologia , Limitação da Mobilidade , Sinfisiotomia/efeitos adversos , Transtornos Urinários/etiologia , Adolescente , Adulto , Idoso , Seguimentos , Humanos , Irlanda , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
6.
Bull Environ Contam Toxicol ; 95(1): 102-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25985871

RESUMO

This study assessed the effect on magnetic susceptibility and organic matter content of arable soil by irrigation with either treated sewage or groundwater. Results indicated that organic matter and magnetic susceptibility values in the soil irrigated with sewage were increased by 7.1 % and 13.5 %, respectively, compared to agricultural soil that irrigated with groundwater. Both the sewage and groundwater irrigated soils contained a significant fraction of ultrafine superpara magnetic grains, as indicated by high frequency dependent susceptibility (χfd > 6 %). The enhancement of soil magnetic properties was determined to be caused by anthropogenic sewage irrigation and agrochemical use by investigation of vertical soil profiles. Magnetic susceptibility parameters were shown to be significantly correlated with organic matter content (y = 0.0057x + 1.3439, R(2) = 0.09, p < 0.05). This work indicates that measurements of magnetic susceptibility may offer a rapid first step for identifying the potential pollution in arable soils.


Assuntos
Irrigação Agrícola , Água Subterrânea/análise , Compostos Orgânicos/análise , Esgotos/análise , Poluentes do Solo/análise , Solo/química , China , Monitoramento Ambiental/métodos , Geografia , Magnetismo
7.
Eur J Appl Physiol ; 114(7): 1413-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24658878

RESUMO

PURPOSE: Pacing strategies have been reported to occur during continuous cyclical exercises. However, currently no studies have examined if pacing takes place during repeated maximal voluntary muscle contractions (MVCs). Accordingly, the purpose of this study was to examine if informing subjects on the number of MVCs they would perform would affect force and root mean squared electromyography (EMG), during similar fatiguing protocols. METHODS: Thirty well-trained male subjects completed three fatiguing protocols in a randomized order. In the control condition participants were informed they would perform 12 MVCs, and then completed all 12. In the unknown condition they were not told how many MVCs they would perform, but were stopped after 12. Lastly, in the deception condition they were initially told they would perform only 6 MVCs, but after the 6 contractions they were asked to perform a few more repetitions and were stopped after 12. RESULTS: Compared to the unknown condition, subjects demonstrated greater forces (p < 0.05, ES = 0.35-1.14, 2-7.5%) and biceps EMG (p < 0.05, ES = 0.6, 6%) in the deception condition during the first six MVCs. Additionally, under all conditions subjects applied greater forces in the last repetition (#12) relative to the previous one (#11) (p < 0.06, ES = 0.36-0.5, 2.8-3.8%). CONCLUSIONS: The anticipation of performing a certain number of MVCs led the subjects to utilize different pacing strategies. The results also question the assumption that subjects followed the instruction to exert maximal effort during repeated MVCs.


Assuntos
Contração Isométrica , Fadiga Muscular , Músculo Esquelético/fisiologia , Resistência Física , Volição , Adulto , Antecipação Psicológica , Enganação , Eletromiografia , Teste de Esforço , Humanos , Masculino , Terra Nova e Labrador , Fatores de Tempo , Adulto Jovem
8.
Plant Dis ; 96(9): 1383, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30727187

RESUMO

In September 2010, celery plants with leaf cupping and petiole twisting were observed in commercial production fields located in Barry, Kent, Newago, and Van Buren Counties in Michigan. Long, elliptical lesions were observed on petioles but signs (mycelia, conidia, or acervuli) were not readily observed. Celery petioles were incubated in humid chambers (acrylic boxes with wet paper towels). After 24 h, conidia corresponding to the genus Colletotrichum were observed. Isolations were performed by excising pieces of celery tissue from the lesion margin and placing them on potato dextrose agar (PDA) amended with 30 ppm of rifampicin and 100 ppm of ampicillin. Plates were incubated at 21 ± 2°C under fluorescent light for 5 days. Fungal colony morphology was gray with salmon-colored masses of spores when viewed from above, and carmine when viewed from below. Isolates were single-spored and placed on 30% glycerol in -20°C, and cryoconservation media (20% glycerol, 0.04% yeast extract, 0.1% malt extract, 0.04% glucose, 0.02% K2HPO4) at -80°C. Conidia were 8.5 to 12.0 × 2.8 to 4.0 µm and straight fusiform in shape. Three isolates were confirmed as C. acutatum sensu lato based on sequences of the internal transcribed spacer (ITS) region of the nuclear ribosomal RNA and the 1-kb intron of the glutamine synthase gene (3), both with 100% similarity with Glomerella acutata sequences. Sequences were submitted to GenBank (Accession Nos. JQ951599 and JQ951600 for ITS and GS, respectively). Additionally, C. acutatum specific primer CaIntg was used in combination with the primer ITS4 on 54 isolates from symptomatic celery plants, obtaining the expected 490-pb fragment (1). Koch's postulates were completed by inoculating 4-week-old celery seedlings of cultivars Sabroso, Green Bay, and Dutchess using three plants per cultivar. Prior to inoculation, seedlings were incubated for 16 h in high relative humidity (≥95%) by enclosing the plants in humid chambers. Seven-day-old C. acutatum s. l. colonies were used to prepare the inoculum. Seedlings were spray-inoculated with a C. acutatum s. l. conidial suspension of 1 × 106 conidia/ml in double-distilled water plus Tween 0.01%. Two control seedlings per cultivar were sprayed with sterile, double-distilled water plus 0.01% Tween. Plants were enclosed in bags for 96 h post inoculation and incubated in a greenhouse at 27°C by day/20°C by night with a 16-h photoperiod. Leaf curling was observed on all inoculated plants of the three cultivars 4 days after inoculation (DAI). Petiole lesions were observed 14 to 21 DAI. Conidia were observed in lesions after incubation in high humidity at 21 ± 2°C for 24 to 72 h. Symptomatic tissue was excised and cultured onto PDA and resulted in C. acutatum colonies. Control plants remained symptomless. C. acutatum (4) and C. orbiculare (2) were reported to cause celery leaf curl in Australia in 1966 (2,4). To our knowledge, this is the first report of C. acutatum s. l. infecting celery in Michigan. References: (1) A. E. Brown et al. Phytopathology 86:523, 1996. (2) D. F. Farr and A. Y. Rossman. Fungal Databases. Syst. Mycol. Microbiol. Lab., USDA-ARS. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , 10 September 2010. (3) J. C. Guerber et al. Mycologia 95:872, 2003. (4) D. G. Wright and J. B. Heaton. Austral. Plant Pathol. 20:155, 1991.

9.
Nanotechnology ; 22(45): 455709, 2011 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-22020365

RESUMO

The bioproduction of nanoscale magnetite by Fe(III)-reducing bacteria offers a potentially tunable, environmentally benign route to magnetic nanoparticle synthesis. Here, we demonstrate that it is possible to control the size of magnetite nanoparticles produced by Geobacter sulfurreducens by adjusting the total biomass introduced at the start of the process. The particles have a narrow size distribution and can be controlled within the range of 10-50 nm. X-ray diffraction analysis indicates that controlled production of a number of different biominerals is possible via this method including goethite, magnetite and siderite, but their formation is strongly dependent upon the rate of Fe(III) reduction and total concentration and rate of Fe(II) produced by the bacteria during the reduction process. Relative cation distributions within the structure of the nanoparticles have been investigated by x-ray magnetic circular dichroism and indicate the presence of a highly reduced surface layer which is not observed when magnetite is produced through abiotic methods. The enhanced Fe(II)-rich surface, combined with small particle size, has important environmental applications such as in the reductive bioremediation of organics, radionuclides and metals. In the case of Cr(VI), as a model high-valence toxic metal, optimized biogenic magnetite is able to reduce and sequester the toxic hexavalent chromium very efficiently to the less harmful trivalent form.


Assuntos
Óxido Ferroso-Férrico/metabolismo , Geobacter/metabolismo , Nanopartículas de Magnetita/química , Cromo , Dicroísmo Circular , Nanopartículas de Magnetita/ultraestrutura , Magnetometria , Microscopia Eletrônica de Transmissão , Nanotecnologia , Tamanho da Partícula , Difração de Raios X
10.
Nat Commun ; 12(1): 2069, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824308

RESUMO

The oxygenation of early Earth's atmosphere during the Great Oxidation Event, is generally accepted to have been caused by oceanic Cyanobacterial oxygenic photosynthesis. Recent studies suggest that Fe(II) toxicity delayed the Cyanobacterial expansion necessary for the GOE. This study investigates the effects of Fe(II) on two Cyanobacteria, Pseudanabaena sp. PCC7367 and Synechococcus sp. PCC7336, in a simulated shallow-water marine Archean environment. A similar Fe(II) toxicity response was observed as reported for closed batch cultures. This toxicity was not observed in cultures provided with continuous gaseous exchange that showed significantly shorter doubling times than the closed-culture system, even with repeated nocturnal addition of Fe(II) for 12 days. The green rust (GR) formed under high Fe(II) conditions, was not found to be directly toxic to Pseudanabaena sp. PCC7367. In summary, we present evidence of diurnal Fe cycling in a simulated shallow-water marine environment for two ancestral strains of Cyanobacteria, with increased O2 production under anoxic conditions.


Assuntos
Organismos Aquáticos/metabolismo , Archaea/metabolismo , Ritmo Circadiano , Ferro/metabolismo , Oxigênio/metabolismo , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/crescimento & desenvolvimento , Archaea/efeitos dos fármacos , Archaea/crescimento & desenvolvimento , Atmosfera , Clorofila A/metabolismo , Ferro/toxicidade , Modelos Biológicos , Água do Mar
11.
J Hazard Mater ; 408: 124924, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33385723

RESUMO

The formation of iron-sulfur-arsenic (Fe-S-As) minerals during biogeochemical processes in As contaminated aquifers remains poorly understood despite their importance to understanding As release and transport in such systems. In this study, X-ray absorption and Mössbauer spectroscopies complemented by electron microscopy, and chemical extractions were used to examine vertical changes of As, Fe and S speciation for the example of sediments in the Hetao Basin. Reduction of Fe(III), As(V) and SO42- species were shown to co-occur in the aquifers. Iron oxides were observed to be predominantly goethite and hematite (36 - 12%) and appeared to decrease in abundance with depth. Furthermore, reduced As (including arsenite and As sulfides) and sulfur species (including S(-II), S(-I) and S0) increased from 16% to 76% and from 13% to 44%, respectively. Iron oxides were the major As carrier in the sediments, and the lower groundwater As concentration consists with less desorbable and reducible As in the sediments. The formation of As-Fe sulfides (e.g., As containing pyrite and greigite) induced by redox heterogeneities likely contribute to localized lower groundwater As concentrations. These results help to further elucidate the complex relationship between biogeochemical processes and minerals formation in As contaminated aquifers.

12.
J Hosp Infect ; 108: 55-63, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33122042

RESUMO

The coronavirus disease 2019 pandemic has meant that there is growing pressure on hospital resources, not least the availability of appropriate personal protective equipment (PPE), particularly face masks and respirator masks. Within the field of orthopaedic surgery, it is a common sight to see surgeons wearing 'space suits' (SSs) which comprise a helmet, hood and surgical gown. In this study, the authors made modifications to two different SS systems to incorporate a high-efficiency particulate air (HEPA) filter into the fan inlet to assess their potential as re-usable PPE systems for surgeons with regard to protection from a virus spread via respiratory droplets. The testing was carried out using particle counters upstream and downstream on a mannequin wearing two different SS systems with and without modifications to the fan inlet. The results show that using a layer of HEPA filter, cut to size and sealed to the fan inlet in the helmet, will reduce downstream particulates at the user's mouth by >99.5%; this is equivalent to a respirator mask. HEPA filter material is relatively cheap and can be used repeatedly, making this a viable alternative to disposable, and even resterilized, respirator masks in the setting of a respiratory-droplet-spread viral pandemic.


Assuntos
COVID-19/transmissão , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Procedimentos Ortopédicos/normas , Equipamento de Proteção Individual/provisão & distribuição , Filtros de Ar/estatística & dados numéricos , Filtros de Ar/tendências , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/virologia , Dispositivos de Proteção da Cabeça , Humanos , Manequins , Máscaras , Procedimentos Ortopédicos/estatística & dados numéricos , Material Particulado/análise , Projetos Piloto , Dispositivos de Proteção Respiratória/estatística & dados numéricos , Dispositivos de Proteção Respiratória/tendências , SARS-CoV-2/genética , Trajes Espaciais/tendências , Trajes Espaciais/virologia
13.
Eur Spine J ; 19(10): 1635-42, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20364276

RESUMO

Odontoid fractures currently account for 9-15% of all adult cervical spine fractures, with type II fractures accounting for the majority of these injuries. Despite recent advances in internal fixation techniques, the management of type II fractures still remains controversial with advocates still supporting non-rigid immobilization as the definitive treatment of these injuries. At the NSIU, over an 11-year period between 1 July 1996 and 30 June 2006, 66 patients (n = 66) were treated by external immobilization for type II odontoid fractures. The medical records, radiographs and CT scans of all patients identified were reviewed. Clinical follow-up evaluation was performed using the Cervical Spine Outcomes Questionnaire (CSOQ). The objectives of this study were to evaluate the long-term functional outcome of patients suffering isolated type II odontoid fractures managed non-operatively and to correlate patient age and device type with clinical and functional outcome. Of the 66 patients, there were 42 males and 24 females (M:F = 1.75:1) managed non-operatively for type II odontoid fractures. The mean follow-up time was 66 months. Advancing age was highly correlated with poorer long-term functional outcomes when assessing neck pain (r = 0.19, P = 0.1219), shoulder and arm pain (r = 0.41, P = 0.0007), physical symptoms (r = 0.25, P = 0.472), functional disability (r = 0.24, P = 0.0476) and psychological distress (r = 0.41, P = 0.0007). Patients >65 years displayed a higher rate of pseudoarthrosis (21.43 vs. 1.92%) and established non-union (7.14 vs. 0%) than patients <65 years. The non-operative management of type II odontoid fractures is an effective and satisfactory method of treating type II odontoid fractures, particularly those of a stable nature. However, patients of advancing age have been demonstrated to have significantly poorer functional outcomes in the long term. This may be linked to higher rates of non-union.


Assuntos
Articulação Atlantoaxial/lesões , Articulação Atlantoccipital/lesões , Imobilização/instrumentação , Processo Odontoide/lesões , Fraturas da Coluna Vertebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Articulação Atlantoaxial/diagnóstico por imagem , Articulação Atlantoaxial/fisiopatologia , Articulação Atlantoccipital/diagnóstico por imagem , Articulação Atlantoccipital/fisiopatologia , Estudos de Coortes , Fixadores Externos/tendências , Feminino , Humanos , Imobilização/métodos , Masculino , Pessoa de Meia-Idade , Processo Odontoide/diagnóstico por imagem , Processo Odontoide/fisiopatologia , Radiografia , Fraturas da Coluna Vertebral/diagnóstico , Fraturas da Coluna Vertebral/fisiopatologia , Fatores de Tempo , Adulto Jovem
14.
Foot Ankle Surg ; 16(1): 45-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20152755

RESUMO

BACKGROUND: Overuse ankle injuries have been described in elite athletes and professional ballet dancers however the spectrum of injuries experienced by professional Irish dancers has not been defined. METHODS: A troupe of actively performing dancers from an Irish-dance show were recruited (eight male, ten female; mean age, 26 years). The prevalence of overuse injuries in the right ankle was determined from magnetic resonance imaging. Foot and ankle self-report questionnaires were also completed (AOFAS and FAOS). RESULTS: Only three ankles were considered radiologically normal. Achilles tendinopathy, usually insertional, was the most frequent observation (n=14) followed by plantar fasciitis (n=7), bone oedema (n=2) and calcaneocuboid joint degeneration (n=2). There were limited correlations between MRI patterns and clinical scores indicating that many conditions are sub-clinical. Dancers with ankle pain had poor low (p=0.004) and high (p=0.013) level function. CONCLUSIONS: Overuse ankle injuries are common in Irish dancers. Incorporating eccentric exercises and plantar fascia stretching into a regular training program may benefit this population.


Assuntos
Acidentes de Trabalho , Traumatismos do Tornozelo/diagnóstico , Transtornos Traumáticos Cumulativos/diagnóstico , Dança/lesões , Atividades Cotidianas , Adulto , Traumatismos do Tornozelo/epidemiologia , Distribuição de Qui-Quadrado , Transtornos Traumáticos Cumulativos/epidemiologia , Feminino , Humanos , Irlanda/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Medição da Dor , Prevalência , Qualidade de Vida , Inquéritos e Questionários
15.
Environ Sci Process Impacts ; 22(9): 1877-1887, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32803208

RESUMO

Cadmium (Cd) adversely affects human health by entering the food chain via anthropogenic activity. In order to mitigate risk, a better understanding of the biogeochemical mechanisms limiting Cd mobility in the environment is needed. While Cd is not redox-active, Cd speciation varies (i.e., aqueous, complexed, adsorbed), and influences mobility. Here, the cycling of Cd in relation to initial speciation during the growth of Geobacter sulfurreducens was studied. Either fumarate or ferrihydrite (Fh) was provided as an electron acceptor and Cd was present as: (1) an aqueous cation, (2) an aqueous complex with cysteine, which is often present in metal stressed soil environments, or (3) adsorbed to Fh. During microbial Fe(iii) reduction, the removal of Cd was substantial (∼80% removal), despite extensive Fe(ii) production (ratio Fe(ii)total : Fetotal = 0.8). When fumarate was the electron acceptor, there was higher removal from solution when Cd was complexed with cysteine (97-100% removal) compared to aqueous Cd (34-50%) removal. Confocal laser scanning microscopy (CLSM) demonstrated the formation of exopolymeric substances (EPS) in all conditions and that Cd was correlated with EPS in the absence of Fe minerals (r = 0.51-0.56). Most notable is that aqueous Cd was more strongly correlated with Geobacter cells (r = 0.72) compared to Cd-cysteine complexes (r = 0.51). This work demonstrates that Cd interactions with cell surfaces and EPS, and Cd solubility during metabolic activity are dependent upon initial speciation. These processes may be especially important in soil environments where sulfur is limited and Fe and organic carbon are abundant.


Assuntos
Cisteína/química , Geobacter , Ferro , Adsorção , Cádmio , Compostos Férricos , Minerais , Oxirredução
16.
Ir J Med Sci ; 187(1): 177-182, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28455775

RESUMO

INTRODUCTION: The General Medical Council (GMC) of the UK states that doctors have a duty to train and contribute to the education of colleagues, and that those involved in formal clinical teaching should have a teaching qualification. OBJECTIVES: We sought to evaluate the current levels of engagement of surgical trainees and recently appointed surgical consultants in clinical teaching. METHODS: All trainees who commenced a basic or higher surgical training post during or after 2007 were invited to participate. The electronic questionnaire was administered using the survey tool GetFeedback, collecting information regarding subspecialty, current role, quantity of teaching that respondents engaged in and who they taught and teaching motivations and barriers. RESULTS: There were 128 respondents out of 358 invitations to participate (36% response rate). Less than half (39%) of respondents had attended formal courses on clinical education. Over 70% of respondents engaged in clinical teaching for two or more hours each week. A lack of time and resources were noted as barriers to engaging in teaching. We found a low number of those involved in teaching seeking feedback after teaching sessions. CONCLUSION: In surgery, the apprenticeship model is still the framework for developing the surgeons of the future. In attempting to produce a highly skilled workforce for the future, we rely on those in senior positions to train those coming through; higher surgical trainees are relied on to teach the core surgical trainees and so on. Our study shows a low level of formalisation of this model.


Assuntos
Educação de Pós-Graduação em Medicina/tendências , Cirurgia Geral/educação , Ensino/tendências , Feminino , Hospitais , Humanos , Irlanda , Masculino , Inquéritos e Questionários
17.
J Bone Joint Surg Br ; 89(6): 766-71, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17613501

RESUMO

Our aims were to map the tibial footprint of the posterior cruciate ligament (PCL) using MRI in patients undergoing PCL-preserving total knee replacement, and to document the disruption of this footprint as a result of the tibial cut. In 26 consecutive patients plain radiography and MRI of the knee were performed pre-operatively, and plain radiography post-operatively. The lower margin of the PCL footprint was located a mean of 1 mm (-10 to 8) above the upper aspect of the fibular head. The mean surface area was 83 mm(2) (49 to 142). One-third of patients (8 of 22) had tibial cuts made below the lowest aspect of the PCL footprint (complete removal) and one-third (9 of 22) had cuts extending into the footprint (partial removal). The remaining patients (5 of 22) had footprints unaffected by the cuts, keeping them intact. Our study highlights the wide variation in the location of the tibial PCL footprint when referenced against the fibula. Proximal tibial cuts using conventional jigs resulted in the removal of a significant portion, if not all of the PCL footprint in most of the patients in our study. Our findings suggest that when performing PCL-retaining total knee replacement the tibial attachment of the PCL is often removed.


Assuntos
Artroplastia do Joelho/métodos , Instabilidade Articular/cirurgia , Osteoartrite do Joelho/patologia , Ligamento Cruzado Posterior/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Instabilidade Articular/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Ligamento Cruzado Posterior/diagnóstico por imagem , Ligamento Cruzado Posterior/cirurgia , Radiografia , Método Simples-Cego
18.
J Bone Joint Surg Br ; 88(6): 771-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16720772

RESUMO

This study assessed the frequency of acute injury to the spinal cord in Irish Rugby over a period of ten years, between 1995 and 2004. There were 12 such injuries; 11 were cervical and one was thoracic. Ten occurred in adults and two in schoolboys. All were males playing Rugby Union and the mean age at injury was 21.6 years (16 to 36). The most common mechanism of injury was hyperflexion of the cervical spine and the players injured most frequently were playing at full back, hooker or on the wing. Most injuries were sustained during the tackle phase of play. Six players felt their injury was preventable. Eight are permanently disabled as a result of their injury.


Assuntos
Futebol Americano/lesões , Traumatismos da Medula Espinal/epidemiologia , Traumatismos da Coluna Vertebral/epidemiologia , Atividades Cotidianas , Doença Aguda , Adolescente , Adulto , Vértebras Cervicais/lesões , Avaliação da Deficiência , Humanos , Irlanda/epidemiologia , Masculino , Prognóstico , Estudos Retrospectivos , Traumatismos da Medula Espinal/prevenção & controle , Traumatismos da Medula Espinal/reabilitação , Traumatismos da Coluna Vertebral/prevenção & controle , Traumatismos da Coluna Vertebral/reabilitação
19.
J Bone Joint Surg Br ; 88(3): 406-10, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16498024

RESUMO

Injuries to the spinal cord may be associated with increased healing of fractures. This can be of benefit, but excessive bone growth can also cause considerable adverse effects. We evaluated two groups of patients with fractures of the spinal column, those with neurological compromise (n=10) and those without (n=15), and also a control group with an isolated fracture of a long bone (n=12). The level of transforming growth factor-beta (TGF-beta), was measured at five time points after injury (days 1, 5, 10, 42 and 84). The peak level of 142.79 ng/ml was found at day 84 in the neurology group (p<0.001 vs other time points). The other groups peaked at day 42 and had a decrease at day 84 after injury (p

Assuntos
Traumatismos da Medula Espinal/sangue , Fraturas da Coluna Vertebral/sangue , Fator de Crescimento Transformador beta/sangue , Doença Aguda , Adulto , Feminino , Consolidação da Fratura/fisiologia , Humanos , Masculino , Traumatismos da Medula Espinal/fisiopatologia , Fraturas da Coluna Vertebral/fisiopatologia , Fatores de Tempo
20.
Ir J Med Sci ; 175(1): 20-3, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16615223

RESUMO

BACKGROUND: On October 31st 2002 a system of cumulative penalty points for road traffic offences was introduced. Early evidence suggested a reduction in road traffic accident (RTA) related morbidity. AIMS: To evaluate the persistence of the initial reduction in RTA related spinal injuries following penalty points introduction. METHODS: Retrospective review of all acute spinal trauma admissions to the NSIU between November 1st 1998 and October 31st 2004 (n = 966). Patient demographics and injury aetiology were assessed. Follow-up questionnaires evaluated RTA circumstances. RESULTS: RTA related spinal injuries accounted for 39.3% of NSIU admissions. These injuries were significantly more common in males aged 16-24, drivers (70.8%), on routine journeys (77.5%) and rural roads (48.8%). The highest proportion of accidents occurred during weekends (64.3% from Fri-Sun) and from midnight to 6am (29.3%). CONCLUSIONS: The initial reduction in RTA related spinal injuries has not been sustained. Young male drivers are the greatest at risk group.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/legislação & jurisprudência , Direito Penal , Traumatismos da Coluna Vertebral/epidemiologia , Acidentes de Trânsito/prevenção & controle , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Traumatismos da Coluna Vertebral/etiologia , Traumatismos da Coluna Vertebral/prevenção & controle , Fatores de Tempo
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