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1.
Environ Geochem Health ; 46(3): 93, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38367154

RESUMO

In recent decades, Saiga antelope (Saiga t. tatarica) mass die-offs have become more common. The mass die-off of 2015 in central Kazakhstan, recorded 140,000 individual deaths across multiple herds. Previously, research has shown atmospheric humidity, the bacterium Pasteurella multocida serotype B, and resultant haemorrhagic septicaemia, were the primary cause. However, other synergistic factors may have impacted this process. Here we use a multivariate compositional data analysis (CoDA) approach to assess what other factors may have been involved. We show a pollutant linkage mechanism where relative humidity and dewpoint temperature combine with environmental pollutants, potentially toxic elements (e.g., Hg, As), complex carbon compounds (e.g., Acetone, Toluene), and inorganic compounds (e.g., CHx, SO2) which affected the Saiga during the calving season (start and peak) and at the onset of the mass die-off. We suggest a mechanism for this process. Upon arrival at their carving grounds, the Saiga experienced a sudden precipitation event, a spike in temperatures, and resultant high humidity occurs. The infectious bacterium P. multocida serotype B then spreads. Further, environmental pollutants contained within steppe soils are released to the air, forming localised smog events, these synergistically combine, and mass die-off occurs.


Assuntos
Antílopes , Poluentes Ambientais , Animais , Antílopes/microbiologia , Mudança Climática , Cazaquistão
2.
Sci Total Environ ; 769: 145246, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736251

RESUMO

Potentially Toxic Elements (PTEs) otherwise known as heavy metals are ubiquitous in soils and can have a range of negative health and environmental impacts. In terrestrial systems understanding how PTEs move in the environment is made challenging by the complex interactions within soil and the wider environment and the compositional nature of PTEs. PTEs are compositional because data of individual PTEs within in a sample are ratios which may be under a sum constraint, where individual components sum up to a whole. In this study three different scenarios were considered, one using the centred log ratio transformation (clr) a compositional transformation, the more "traditional" log10 transformation (log10) and untransformed data acting as a comparison (unt) were applied to four different datasets. Three were the Liver, Muscle and Kidney tissue of Eurasian Badgers (Meles meles) and the fourth was soil and data were extracted from a regional geospatial survey. Cluster analysis demonstrated that the clr and log10 transformation were able to resolve compositional trends at the point of the individual sample, whilst unt could not and did not meet the preconditions for the next phase of analysis. At the level of compositional trends between PTEs complex heatmaps demonstrated that clr was able to isolate PTE relationships and highlight commonalities between different datasets, whilst log10 could not. In the final phase, principal component analysis (PCA) of the clr transformation showed similarities between the signals in the soft tissues and the disparities they had with soil, whilst the log10 transformation was unable to achieve this. Overall, the clr transformation was shown to perform more consistently under a variety of analytical scenarios and the compositional approach will provide more realistic interpretations about PTEs in both soil and animal soft tissue than the log10 or unt conditions.


Assuntos
Metais Pesados , Poluentes do Solo , Animais , Ecotoxicologia , Monitoramento Ambiental , Metais Pesados/análise , Metais Pesados/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
4.
Sci Total Environ ; 762: 143087, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33131870

RESUMO

Potentially Toxic Elements (PTEs) in Badgers (Meles meles), otherwise known as heavy metals, are unique amongst environmental pollutants occurring, both naturally and anthropogenically. PTEs have a broad range of negative health and environmental effects, therefore identifying their sources and pathways through the environment is imperative for public health policy. This is difficult in terrestrial systems due to the compositional nature of soil geochemistry. In this study, a compositional statistical approach was used to identify how PTEs accumulate in a terrestrial carnivorous mammal, Eurasian Badgers (Meles meles). Compositional principal component analysis (PCA) was used on geochemical data from the Tellus survey, the soil baseline and badger tissue data to map geo-spatial patterns of PTEs and show accumulative trends measured in time. Mapping PCs identified distinct regions of PTE presence in soil and PTE accumulation in badger tissues in Northern Ireland. PTEs were most elevated in liver, kidney and then muscle tissues. Liver and kidney showed the most distinct geo-spatial patterns of accumulation and muscle was the most depleted. PC1 and 2 for each type were modelled using generalised additive mixed models (GAMM) to identify trends through time. PC1 for the liver and muscle were associated with rainfall and ∂N15 in the liver, showing a link to diet and a bioaccumulation pathway, whilst PC2 for both tissues was associated with mean temperature, showing a link to seasonal activity and a bioaccessibility pathway. However, in kidney tissue these trends are reversed and PC1 was associated with bioaccessibility and PC2 with bioaccumulation. Combined these techniques can elucidate both geo-spatial trends in PTEs and the mechanisms by which they move in environment and in future may be an effective tool for assessing PTE bioavailability in environmental health surveys.


Assuntos
Metais Pesados , Mustelidae , Poluentes do Solo , Animais , Metais Pesados/análise , Irlanda do Norte , Solo , Poluentes do Solo/análise
5.
Foot (Edinb) ; 43: 101661, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32120285

RESUMO

INTRODUCTION: The aim of this paper is to present validated patient reported outcomes for MIS Distal Metatarsal Metaphyseal Osteotomy (DMMO) in the treatment of metatarsalgia. The study aims to evaluate the DMMO procedure, report patient satisfaction with the operated foot and report any complications of this procedure. PATIENTS AND METHODS: Between 2014 and 2016, patients who had failed conservative treatment for metatarsalgia were identified in the orthopaedic outpatient clinic. Twenty four consecutive patients requiring DMMO plus/minus toe straightening were prospectively studied. Patients requiring additional procedures at the time of surgery were excluded. Patients completed the validated Manchester-Oxford Foot Questionnaire (MOXFQ) three weeks pre-operatively and 1 year postoperatively. The MOXFQ results were analysed using Paired t-tests. A supplementary question was asked regarding patient satisfaction with the operated foot. RESULTS: There were 20 women and 4 men with a mean age of 64 years (sd 8.6). Statistically significant differences were found between the pre and postoperative MOXFQ. The postoperative MOXFQ score demonstrated a poorer result for two patients, no change for two patients and improvement in 20 patients, with four of these patients recording the lowest possible score. There was a 29.5 point improvement in mean metric MOXFQ Index score. Seventy-nine percent (n = 19) of patients were satisfied or very satisfied with the operated foot. The average recoil of the metatarsal heads following DMMO was M2 4.01 mm, M3 4.55 mm, M4 4.16 mm. There was one delayed union and no non-unions. Further reported complications were a gastric bleed, pulmonary embolism (VTE), and one intra operative broken burr. CONCLUSION: Our study demonstrates a clinically important and statistically significant improvement in patient reported outcomes following DMMO, with 79% of patients satisfied or very satisfied with this procedure. The average recoil of the metatarsal heads following DMMO was M2 4.01 mm, M3 4.55 mm, M4 4.16 mm with one delayed union and no non-unions.


Assuntos
Ossos do Metatarso/cirurgia , Metatarsalgia/cirurgia , Osteotomia , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Metatarsalgia/diagnóstico por imagem , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Medidas de Resultados Relatados pelo Paciente , Satisfação do Paciente
6.
Bone Joint J ; 98-B(10): 1376-1381, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27694592

RESUMO

AIMS: This is the first prospective study to report the pre- and post-operative patient reported outcomes and satisfaction scores following excision of interdigital Morton's neuroma. PATIENTS AND METHODS: Between May 2006 and April 2013, we prospectively studied 99 consecutive patients (111 feet) who were to undergo excision of a Morton's neuroma. There were 78 women and 21 men with a mean age at the time of surgery of 56 years (22 to 78). Patients completed the Manchester-Oxford Foot Questionnaire (MOXFQ), Short Form-12 (SF-12) and a supplementary patient satisfaction survey three months pre-operatively and six months post-operatively. RESULTS: Statistically significant differences were found between the mean pre- and post-operative MOXFQ and the physical component of the SF-12 scores (p = 0.00081 and p = 0.00092 respectively). Most patients reported their overall satisfaction as excellent (n = 49, 49.5%) or good (n = 29, 29.3%), but ten patients were dissatisfied, reporting poor (n = 8, 8.1%) or very poor (n = 2, 2.0%) results. Only 63 patients (63%) were pain-free at follow-up: in eight patients (8.1%), the MOXFQ score worsened. There was no statistically significant difference in outcome between surgery on single or multiple sites. However, the MOXFQ scores were significantly worse after revision surgery (p = 0.004). CONCLUSIONS: The patient-reported outcomes after resection of a symptomatic Morton's neuroma are acceptable but may not be as good as earlier studies suggest. Surgery at several sites can be undertaken safely but caution should be exercised when considering revision surgery. Cite this article: Bone Joint J 2016;98-B:1376-81.


Assuntos
Pé/cirurgia , Neuroma Intermetatársico/cirurgia , Procedimentos Ortopédicos/métodos , Satisfação do Paciente , Adulto , Idoso , Feminino , Seguimentos , Pé/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Intermetatársico/fisiopatologia , Período Pós-Operatório , Estudos Prospectivos , Amplitude de Movimento Articular , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
7.
Bone Joint J ; 98-B(7): 945-51, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27365473

RESUMO

AIMS: To examine the mid-term outcome and cost utility of the BioPro metallic hemiarthroplasty for the treatment of hallux rigidius. PATIENTS AND METHODS: We reviewed 97 consecutive BioPro metallic hemiarthroplasties performed in 80 patients for end-stage hallux rigidus, with a minimum follow-up of five years. There were 19 men and 61 women; their mean age was 55 years (22 to 74). No patient was lost to follow-up. RESULTS: A total of 12 patients (15 first metatarso-phalangeal joints (MTPJs)) required a revision; one for infection, two for osteolysis and 12 for pain. The all cause rate of survival at five years was 85.6% (95% confidence interval (CI) 83.5 to 87.9). Younger age was a significant predictor of revision (odds ratio 1.09, 95% CI 1.02 to 1.17, p = 0.014) on excluding infection and adjusting for confounding variables (Cox regression). Significant improvements were demonstrated at five years in the Manchester Oxford Foot Questionnaire (13.9, 95% CI 10.5 to 17.2) and in the physical component of the Short Form-12 score (6.5, 95% CI 4.1 to 8.9). The overall rate of satisfaction was 75%. The cost per quality adjusted life year at five years, accounting for a 14% rate of revision was between £4431 and £6361 depending on the complexity and morbidity of the patient. CONCLUSION: The BioPro hemiarthroplasty offers good short to mid-term functional outcome and is a cost effective intervention. The relatively high revision rate is associated with younger age and perhaps the use of this implant should be limited to older patients. Cite this article: Bone Joint J 2016;98-B:945-51.


Assuntos
Hallux Rigidus/cirurgia , Hemiartroplastia/instrumentação , Prótese Articular , Articulação Metatarsofalângica/cirurgia , Adulto , Fatores Etários , Idoso , Artrodese , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Anos de Vida Ajustados por Qualidade de Vida , Reoperação , Estudos Retrospectivos , Adulto Jovem
10.
Foot Ankle Surg ; 17(2): e34-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21549970

RESUMO

Black bone disease is a rare manifestation of long term treatment with tetracyclines. We report the case of a patient who underwent surgery for bilateral hallux valgus and was found to have black discolouration of both first rays. This was subsequently related to previous long term Minocycline use. The unique features of this case relate to the location of the discolouration and the normal physical properties of the bone and soft tissues at surgery despite heavy pigmentation. Healing is now complete and follow-up at two years confirmed excellent clinical and radiological outcomes.


Assuntos
Antibacterianos/efeitos adversos , Doenças Ósseas/induzido quimicamente , Hiperpigmentação/induzido quimicamente , Ossos do Metatarso/patologia , Minociclina/efeitos adversos , Falanges dos Dedos do Pé/patologia , Feminino , Hallux Valgus/cirurgia , Humanos , Achados Incidentais , Pessoa de Meia-Idade
11.
J Contam Hydrol ; 112(1-4): 1-14, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19683832

RESUMO

'Bioimmobilization' of redox-sensitive heavy metals and radionuclides is being investigated as a way to remediate contaminated groundwater and sediments. In one approach, growth-limiting substrates are added to the subsurface to stimulate the activity of targeted groups of indigenous microorganisms and create conditions favorable for the microbially-mediated reductive precipitation ('bioreduction') of targeted contaminants. We present a theoretical framework for modeling this process that modifies conventional geochemical reaction path modeling to include thermodynamic descriptions for microbial growth and may be called biogeochemical reaction path modeling. In this approach, the actual microbial community is represented by a synthetic microbial community consisting of a collection of microbial groups; each with a unique growth equation that couples a specific pair of energy yielding redox reactions. The growth equations and their computed standard-state free energy yields are appended to the thermodynamic database used in conventional geochemical reaction path modeling, providing a direct coupling between chemical species participating in both microbial growth and geochemical reactions. To compute the biogeochemical reaction paths, growth substrates are reacted incrementally with the defined geochemical environment and the coupled equations are solved simultaneously to predict reaction paths that display changing microbial biomass, community composition (i.e. the fraction of total biomass in each microbial group), and the aqueous and mineral composition of the system, including aqueous speciation and oxidation state of the targeted contaminants. The approach, with growth equations derived from the literature using well-known bioenergetics principles, was used to predict the results of a laboratory microcosm experiment and an in situ field experiment that investigated the bioreduction of uranium. Predicted effects of ethanol or acetate addition on uranium concentration and speciation, major ion geochemistry, mineralogy, microbial biomass and community composition were in qualitative agreement with experimental observations although the available data precluded rigorous model testing. While originally developed for use in better understanding of bioimmobilization of heavy metals and radionuclides, the modeling approach is potentially useful for exploring the coupling of microbial growth and geochemical reactions in a variety of other basic and applied biotechnology research settings.


Assuntos
Biomassa , Microbiologia Ambiental , Modelos Biológicos , Modelos Químicos , Urânio/metabolismo , Ácido Acético , Biodegradação Ambiental , Proliferação de Células , Etanol , Substâncias Perigosas/metabolismo , Termodinâmica
12.
Eur J Cancer ; 45(4): 551-60, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18996690

RESUMO

BACKGROUND: Few data exist regarding the use of complementary and alternative medicine (CAM) by unaffected women at high risk of breast cancer. METHODS: Self-reported CAM use by women from multiple-case breast cancer families was obtained by questionnaire. Factors associated with CAM use were assessed using multiple logistic regression. RESULTS: Of 892 women, 55% (n=489) used CAM, 6% (n=53) specifically to prevent cancer. CAM use was independently associated with tertiary education level (OR 2.56, 95% CI 1.83-3.58, p<0.001), greater physical activity (OR 1.05 per hour of physical activity/week, 95% CI 1.00-1.10, p=0.049), greater anxiety (OR 1.92, 95% CI 1.16-3.16, p=0.01), not currently smoking (OR 0.64, 95% CI 0.42-0.97, p=0.037) and lower perceived BC risk (OR 0.82 per 20 percentage points, 95% CI 0.72-0.94, p=0.005). CONCLUSIONS: The majority of high-risk women use CAM, but mostly for reasons other than cancer prevention. Most predictors of CAM use are consistent with the limited literature for women at high risk for cancer.


Assuntos
Neoplasias da Mama/prevenção & controle , Terapias Complementares/estatística & dados numéricos , Síndromes Neoplásicas Hereditárias/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/psicologia , Proteínas Reguladoras de Apoptose , Atitude Frente a Saúde , Austrália , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/psicologia , Terapias Complementares/psicologia , Escolaridade , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Atividade Motora , Mutação , Nova Zelândia , Ubiquitina-Proteína Ligases/genética , Adulto Jovem
13.
Foot (Edinb) ; 19(4): 197-200, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20307476

RESUMO

BACKGROUND: Calcaneal fractures are rare, but debilitating injuries, which occur frequently in younger individuals. The economic impact of the residual long-term disability that may occur after these injuries is therefore disproportionate to their incidence. The aim of this study was to review the epidemiology and injury patterns of this injury. METHODS: Data was extracted from a computer database, which prospectively coded all orthopaedic trauma events in a single unit between January 1995 and June 2005. Over this period 697 patients sustaining 752 fractures (55 bilateral) were treated in our unit. The patient's demographic details were prospectively recorded, together with details of their injury and primary treatment. The radiographs of a subgroup of patients were retrospectively examined in detail. RESULTS: The annual incidence of fracture was 11.5 per 100,000, and occurred 2.4 times more frequently in males than females. In males, the incidence was 16.5/100,000/year, with a peak incidence in the age range 20-29 (21.6/100,000/year). In females, the overall incidence was 6.26/100,000/year, with a more even spread throughout the age cohorts and showing a gradual increase in incidence towards the post-menopausal years. The majority of fractures were sustained in falls from a height (71.5%), and 64.3% of these were from 6 feet and above. Only 18.8% of fractures occurred in the workplace, and although manual workers made up the largest occupational group, significant numbers occurred in both unemployed and the retired. Most injuries occurred in isolation but the most commonly seen concomitant injuries were lower limb (13.2%) or spinal injuries (6.3%). Conventional radiography in a subgroup of the patients showed an average Böhler's angle of 16.5 degrees with no difference between the males and females. There was a strong association between the severity of the fracture, as assessed using the Sanders classification on computerised tomography, and the degree of depression of the Böhler's angle (p=0.002).


Assuntos
Calcâneo/lesões , Fraturas Ósseas/epidemiologia , Adulto , Idoso , Feminino , Fraturas Ósseas/etiologia , Fraturas Ósseas/patologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Spinal Cord ; 46(10): 707-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18317486

RESUMO

STUDY DESIGN: Case report. OBJECTIVE: To report an intramedullary germinoma associated with congenital adrenal hyperplasia (CAH). METHOD: We report a 14-year-old white male with CAH who was found to have an intramedullary germinoma of the conus medullaris. Presentation and evaluation were for progressive urinary incontinence. A brief review of relevant literature was presented. RESULTS: Cases where germinomas have occurred simultaneously with CAH have been identified intracranially, but to our knowledge, this is the first case of CAH and intramedullary spinal cord germinoma occurring simultaneously. CONCLUSION: Although rare, primary intramedullary germinomas do occur. The association between CAH and spinal cord germinoma should be considered by clinicians.


Assuntos
Hiperplasia Suprarrenal Congênita/complicações , Germinoma/complicações , Neoplasias da Medula Espinal/complicações , Adolescente , Hiperplasia Suprarrenal Congênita/diagnóstico , Germinoma/diagnóstico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neoplasias da Medula Espinal/diagnóstico
15.
Ground Water ; 46(2): 295-304, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18194316

RESUMO

Passive multilevel samplers (MLS) containing a solid matrix for microbial colonization were used as in situ microcosms in conjunction with a push-pull biostimulation experiment designed to promote biological U(VI) and Tc(VII) reduction. MLS were deployed at 24 elevations in the injection well and two downgradient wells to investigate the spatial variability in microbial community composition and growth prior to and following biostimulation. The microbial community was characterized by real-time quantitative polymerase chain reaction (Q-PCR) quantification of bacteria, NO(3)(-)-reducing bacteria (nirS and nirK), delta-proteobacteria, Geobacter sp., and methanogens (mcrA). Pretest cell densities were low overall but varied substantially with significantly greater bacterial populations detected at circumneutral pH (t-test, alpha= 0.05), suggesting carbon substrate and low pH limitations of microbial activity. Although pretest cell densities were low, denitrifying bacteria were dominant members of the microbial community. Biostimulation with an ethanol-amended ground water resulted in concurrent NO(3)(-) and Tc(VII) reduction, followed by U(VI) reduction. Q-PCR analysis of MLS revealed significant (1 to 2 orders of magnitude, Mann-Whitney U-test, alpha= 0.05) increases in cell densities of bacteria, denitrifiers, delta-proteobacteria, Geobacter sp., and methanogens in response to biostimulation. Traditionally, characterization of sediment samples has been used to investigate the microbial community response to biostimulation; however, collection of sediment samples is expensive and not conducive to deep aquifers or temporal studies. The results presented demonstrate that push-pull tests with passive MLS provide an inexpensive approach to determine the effect of biostimulation on contaminant concentrations, geochemical conditions, and the microbial community composition and function.


Assuntos
Fenômenos Fisiológicos Bacterianos , Microbiologia da Água , Sequência de Bases , Primers do DNA , DNA Bacteriano/isolamento & purificação , Concentração de Íons de Hidrogênio , Reação em Cadeia da Polimerase
16.
Clin Genet ; 70(3): 198-206, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16922722

RESUMO

This study prospectively evaluated the utilization of cancer risk management strategies in a multi-institutional cohort of BRCA1 and BRCA2 mutation carriers using a self-report questionnaire. Of 142 unaffected female mutation carriers, 70 (49%) had elected to receive their mutation result. Of those who knew their mutation result, 11% underwent bilateral mastectomy (BM), 29% had bilateral oophorectomy (BO), 78% performed regular breast self-examination (BSE), and 80%, 89%, 67%, and 0% had at least annual clinical breast examination (CBE), mammography, transvaginal ultrasound (TVU), and CA125, respectively. A further 20%, 7%, 0%, 21%, and 75%, respectively, reported never having had these tests. For women who elected not to receive their mutation result, 0% underwent BM, 6% underwent BO, and 77%, 42%, 56%, 7%, and 0% had regular BSE, CBE, mammography, TVU, and CA125, respectively. Only one woman used chemoprevention outside a clinical trial. Uptake of prophylactic surgery and screening was associated with knowing one's mutation status (for all behaviors except BSE), age (for BO and CBE) and residence (for mammography). In this cohort, the minority of mutation carriers utilized risk-reducing surgery or chemoprevention and a substantial minority were not undergoing regular cancer-screening tests.


Assuntos
Neoplasias da Mama/prevenção & controle , Genes BRCA1 , Genes BRCA2 , Triagem de Portadores Genéticos , Predisposição Genética para Doença , Adulto , Idoso , Neoplasias da Mama/genética , Quimioprevenção , Estudos de Coortes , Feminino , Testes Genéticos , Heterozigoto , Humanos , Mamografia , Mastectomia , Pessoa de Meia-Idade , Mutação , Ovariectomia , Estudos Prospectivos , Risco
17.
Microb Ecol ; 47(1): 80-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15259272

RESUMO

Previous studies have shown that sulfate-reduction activity occurs in a heterogeneous manner throughout the terrestrial subsurface. Low-activity regions are often observed in the presence of clay minerals. Here we report that clays inhibit sulfate reduction activity in sediments and in a pure culture of Desulfovibrio vulgaris. Clay minerals including bentonite and kaolinite inhibited sulfate reduction by 70-90% in sediments. Intact clays and clay colloids or soluble components, capable of passing through a 0.2-microm filter, were also inhibitory to sulfate-reducing bacteria. Other adsorbent materials, including anion or cation exchangers and a zeolite, did not inhibit sulfate reduction in sediments, suggesting that the effect of clays was not due to their cation-exchange capacity. We observed a strong correlation between the Al2O3 content of clays and their relative ability to inhibit sulfate reduction in sediments (r2 = 0.82). This suggested that inhibition might be a direct effect of Al3+ (aq) on the bacteria. We then tested pure aluminum oxide (Al2O3) and showed it to act in a similar manner to clay. As dissolved aluminum is known to be toxic to a variety of organisms at low concentrations, our results suggest that the effects of clay on sulfate-reducing bacteria may be directly due to aluminum. Thus, our experiments provide an explanation for the lack of sulfate-reduction activity in clay-rich regions and presents a mechanism for the effect.


Assuntos
Bentonita/química , Desulfovibrio/metabolismo , Sedimentos Geológicos/microbiologia , Caulim/química , Oxirredução/efeitos dos fármacos , Sulfatos/metabolismo , Óxido de Alumínio/química , Óxido de Alumínio/toxicidade , Bentonita/toxicidade , Desulfovibrio/ultraestrutura , Água Doce , Caulim/toxicidade , Microscopia Eletrônica de Varredura , Oklahoma
18.
FEMS Microbiol Ecol ; 48(3): 333-44, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19712303

RESUMO

Methanotrophic bacteria play an important role in global cycling of carbon and co-metabolism of contaminants. Methanotrophs from pristine regions of the Snake River Plain Aquifer (SRPA; Idaho, USA) were studied in order to gain insight into the native groundwater communities' genetic potential to carry out TCE co-metabolism. Wells were selected that were proximal to a TCE plume believed to be undergoing natural attenuation. Methane concentrations ranged from 1 to >1000 nM. Carbon isotope ratios and diversity data together suggest that the SRPA contains active communities of methanotrophs that oxidize microbially produced methane. Microorganisms removed from groundwater by filtration were used as inocula for enrichments or frozen immediately and DNA was subsequently extracted for molecular characterization. Primers that specifically target methanotroph 16S rRNA genes or genes that code for subunits of soluble or particulate methane monooxygenase, mmoX and pmoA, respectively, were used to characterize the indigenous methanotrophs via PCR, cloning, RFLP analysis, and sequencing. Type I methanotroph clones aligned with Methylomonas, Methylocaldum, and Methylobacter sequences and a distinct 16S rRNA phylogenetic lineage grouped near Methylobacter. The majority of clone sequences in type II methanotroph 16S rRNA, pmoA, and mmoX gene libraries grouped closely with sequences in the Methylocystis genus. A subset of the type II methanotroph clones from the aquifer had sequences that aligned most closely to Methylosinus trichosporium OB3b and Methylocystis spp., known TCE-co-metabolizing methanotrophs.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Metano/metabolismo , Microbiologia do Solo , Microbiologia da Água , Bactérias/isolamento & purificação , Bactérias/metabolismo , Proteínas de Bactérias/genética , Análise por Conglomerados , Impressões Digitais de DNA/métodos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Idaho , Oxigenases de Função Mista/genética , Dados de Sequência Molecular , Oxirredução , Filogenia , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Silicatos
19.
Knee ; 10(2): 193-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12788006

RESUMO

There are many different total knee replacements on the market. Most have undergone design changes since they were introduced. The manufacturers claim these changes are necessary to improve outcomes of their products. Johnson and Johnson changed their press fit condylar (PFC) knee to PFC Sigma. One of the reasons for the change was to improve patella tracking by combining the deeply radiused trochlear groove of the PFC cruciate sacrificing knee with the natural asymmetrical valgus angle of the PFC cruciate retaining knee. In 1995 we started a prospective audit of our knee replacements. We analysed our early outcomes to test this theory. Group 1 consisted of 468 patients who underwent 543 PFC replacements. Group 2 consisted of 359 patients who underwent 423 Sigma knee replacements. An audit nurse saw all the patients preoperatively and an American Knee Society Score was done. Operative details were recorded. Patients were followed up by an audit nurse at a dedicated knee clinic. The same surgeons using the same instrumentation carried out the operations. The change in design reduced the lateral release rate by 50% from 32 to 16%. The complications were similar in both groups and there was no difference in the outcomes at 6 months. The change in design from the PFC to the Sigma knee has had an effect in reducing the lateral release rate, without affecting the early outcomes. We plan to continue this audit to see if the change leads to less patellar problems in the future.


Assuntos
Artroplastia do Joelho , Artropatias/fisiopatologia , Artropatias/cirurgia , Articulação do Joelho , Osteotomia , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos , Artroplastia do Joelho/mortalidade , Desenho de Equipamento , Hemoglobinas/análise , Humanos , Incidência , Auditoria Médica , Osteotomia/métodos , Período Pós-Operatório , Estudos Prospectivos , Amplitude de Movimento Articular , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do Tratamento
20.
J Bone Joint Surg Am ; 84(11): 2010-5, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12429763

RESUMO

BACKGROUND: Closed reduction and internal fixation is the preferred initial treatment for young active patients who sustain a displaced intracapsular hip fracture. However, there is a paucity of information on the outcome in patients in whom this procedure fails and who subsequently require revision to a total hip arthroplasty. The purpose of this study was to compare a group of patients with a displaced intracapsular fracture who required early salvage total hip arthroplasty following failure of internal fixation within the first year after fracture with a group treated with primary total joint replacement for treatment of the same type of fracture. METHODS: With use of a matched-pairs case-control design, a group of 107 patients, between the ages of sixty and eighty years, who required an early salvage total hip arthroplasty with cement following failed reduction and internal fixation of a displaced intracapsular hip fracture (Group I) was compared with an age and gender-matched group of patients who had undergone total hip arthroplasty with cement as the primary procedure for the treatment of such a fracture (Group II). RESULTS: During the first year after the arthroplasty, there were fifty-two early complications in thirty-nine patients in Group I and twenty-two complications in fourteen patients in Group II (p < 0.05). There were significantly more superficial infections and dislocations in Group I (p < 0.05). The rate of revision beyond one year was greater and the overall prosthetic survival rate at both five and ten years postoperatively was significantly worse in Group I (log-rank test, p < 0.05). The functional outcomes at one year and at the time of final follow-up were also significantly worse in Group I. CONCLUSIONS: Reduction and internal fixation will continue to be used as the primary treatment of displaced intracapsular fractures in many younger patients because of the benefits of preservation of the normal hip joint. However, patients should be counseled that if this method of treatment is unsuccessful and requires revision to a total hip arthroplasty with cement, the risk of early complications is higher and hip function may be poorer than if the arthroplasty had been performed as a primary procedure.


Assuntos
Artroplastia de Quadril , Artroplastia , Fixação Interna de Fraturas , Fraturas do Quadril/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Reoperação , Falha de Tratamento , Resultado do Tratamento
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