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AIMS: To summarize the results of clinical studies of insulin icodec, an investigational insulin analog designed for once-weekly administration, in adults with type 1 and type 2 diabetes. METHODS: Thirteen published articles describing clinical studies of insulin icodec were identified in PubMed, and data pertinent to key study outcomes were selected for inclusion in this review. RESULTS: In insulin-naïve and insulin-treated individuals, icodec demonstrated efficacy in glycaemic control superior or noninferior to that of insulins glargine U100, glargine U300 and degludec. Icodec exhibited a safety profile comparable to marketed insulins, with the exception of hypoglycaemic event rates. CONCLUSIONS: As a once-weekly alternative to daily basal insulin, icodec is expected to improve patient adherence and satisfaction, reducing the required number of injections per year from 365 to 52 and providing a dosing option potentially attractive to a wide range of insulin users. However, clinical data suggest a notable risk of hypoglycaemia with weekly icodec administration, especially in individuals with type 1 diabetes.
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Newcastle disease (ND) is a notifiable disease affecting chickens and other avian species caused by virulent strains of Avian paramyxovirus type 1 (APMV-1). While outbreaks of ND can have devastating consequences, avirulent strains of APMV-1 generally cause subclinical infections or mild disease. However, viruses can cause different levels of disease in different species and virulence can evolve following cross-species transmission events. This report describes the detection of three cases of avirulent APMV-1 infection in Great Britain (GB). Case 1 emerged from the 'testing to exclude' scheme in chickens in Shropshire while cases 2 and 3 were made directly from notifiable avian disease investigations in chicken broilers in Herefordshire and on premises in Wiltshire containing ducks and mixed species, respectively). Class II/genotype I.1.1 APMV-1 from case 1 shared 99.94% identity to the Queensland V4 strain of APMV-1. Class II/genotype II APMV-1 was detected from case 2 while the class II/genotype I.2 virus from case 3 aligned closely with strains isolated from Anseriformes. Exclusion of ND through rapid detection of avirulent APMV-1 is important where clinical signs caused by avirulent or virulent APMV-1s could be ambiguous. Understanding the diversity of APMV-1s circulating in GB is critical to understanding disease threat from these adaptable viruses.
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Doenças das Aves , Doença de Newcastle , Animais , Galinhas , Reino Unido/epidemiologia , Vírus da Doença de Newcastle/genética , Doença de Newcastle/epidemiologia , Doença de Newcastle/diagnóstico , FilogeniaRESUMO
Newcastle disease (ND) is caused by virulent forms of avian paramyxovirus-1 (APMV-1) and is an economically important disease of poultry world-wide. Pigeon paramyxovirus 1 (PPMV-1), a sub-group of APMV-1 is endemic in Columbiformes and can cause infections of poultry. An outbreak of ND in partridges in Scotland, UK, in 2006 (APMV-1/partridge/UK(Scotland)/7575/06) was identified as a class II, genotype VI.2.1.1.2.1, more commonly associated with PPMV-1. It has been hypothesized that game birds may be a route of transmission into commercial poultry settings due to the semi-feral rearing system, which potentially brings them into contact with both wild-birds and poultry species. Therefore, the pathogenesis and transmission of APMV-1/partridge/UK(Scotland)/7575/06 in game birds and chickens was investigated, and compared to a contemporary PPMV-1 isolate, PPMV-1/pigeon/UK/015874/15. Viral shedding and seroconversion profiles demonstrated that pheasants were susceptible to infection with APMV-1/partridge/UK(Scotland)/7575/06 with limited clinical signs observed although they were able to excrete and transmit virus. In contrast, partridges and pheasants showed limited infection with PPMV-1/pigeon/UK/015874/15, causing mild clinical disease. Chickens, however, were productively infected and were able to transmit virus in the absence of clinical signs. From the data, it can be deduced that whilst game birds may play a role in the transmission and epidemiology of genotype VI.2 APMV-1 viruses, the asymptomatic nature of circulation within these species precludes evaluation of natural infection by clinical surveillance. It therefore remains a possibility that genotype VI.2 APMV-1 infection in game birds has the potential for asymptomatic circulation and remains a potential threat to avian production systems.RESEARCH HIGHLIGHTS Demonstration of infection of game birds with Pigeon paramyxovirus-1 (PPMV-1).There are differing dynamics of infection between different game bird species.Differing dynamics of infection between different PPMV-1 isolates and genotypes in game birds and chickens.
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Galinhas , Doença de Newcastle , Animais , Filogenia , Vírus da Doença de Newcastle , Aves Domésticas , Codorniz , GenótipoRESUMO
Coagulation dysfunction and thrombosis are major complications in patients with coronavirus disease 2019 (COVID-19). Patients on oral anticoagulants (OAC) prior to diagnosis of COVID-19 may therefore have better outcomes. In this multicentre observational study of 5 883 patients (≥18 years) admitted to 26 UK hospitals between 1 April 2020 and 31 July 2020, overall mortality was 29·2%. Incidences of thrombosis, major bleeding (MB) and multiorgan failure (MOF) were 5·4%, 1·7% and 3·3% respectively. The presence of thrombosis, MB, or MOF was associated with a 1·8, 4·5 or 5·9-fold increased risk of dying, respectively. Of the 5 883 patients studied, 83·6% (n = 4 920) were not on OAC and 16·4% (n = 963) were taking OAC at the time of admission. There was no difference in mortality between patients on OAC vs no OAC prior to admission when compared in an adjusted multivariate analysis [hazard ratio (HR) 1·05, 95% confidence interval (CI) 0·93-1·19; P = 0·15] or in an adjusted propensity score analysis (HR 0·92 95% CI 0·58-1·450; P = 0·18). In multivariate and adjusted propensity score analyses, the only significant association of no anticoagulation prior to diagnosis of COVID-19 was admission to the Intensive-Care Unit (ICU) (HR 1·98, 95% CI 1·37-2·85). Thrombosis, MB, and MOF were associated with higher mortality. Our results indicate that patients may have benefit from prior OAC use, especially reduced admission to ICU, without any increase in bleeding.
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Anticoagulantes/uso terapêutico , COVID-19/complicações , Trombose/complicações , Trombose/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/terapia , Feminino , Hemorragia/induzido quimicamente , Hospitalização , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Trombose/epidemiologia , Reino Unido/epidemiologiaRESUMO
BACKGROUND: MDM2/MDMX proteins are frequently elevated in hormone receptor-positive (ER+) breast cancer. We sought to determine the antitumor efficacy of the combination of ALRN-6924, a dual inhibitor of MDM2/MDMX, with chemotherapy in ER+ breast cancer models. METHODS: Three hundred two cell lines representing multiple tumor types were screened to confirm the role of TP53 status in ALRN-6924 efficacy. ER+ breast cancer cell lines (MCF-7 and ZR-75-1) were used to investigate the antitumor efficacy of ALRN-6924 combination. In vitro cell proliferation, cell cycle, and apoptosis assays were performed. Xenograft tumor volumes were measured, and reverse-phase protein array (RPPA), immunohistochemistry (IHC), and TUNEL assay of tumor tissues were performed to evaluate the in vivo pharmacodynamic effects of ALRN-6924 with paclitaxel. RESULTS: ALRN-6924 was active in wild-type TP53 (WT-TP53) cancer cell lines, but not mutant TP53. On ER+ breast cancer cell lines, it was synergistic in vitro and had enhanced in vivo antitumor activity with both paclitaxel and eribulin. Flow cytometry revealed signs of mitotic crisis in all treatment groups; however, S phase was only decreased in MCF-7 single agent and combinatorial ALRN-6924 arms. RPPA and IHC demonstrated an increase in p21 expression in both combinatorial and single agent ALRN-6924 in vivo treatment groups. Apoptotic assays revealed a significantly enhanced in vivo apoptotic rate in ALRN-6924 combined with paclitaxel treatment arm compared to either single agent. CONCLUSION: The significant synergy observed with ALRN-6924 in combination with chemotherapeutic agents supports further evaluation in patients with hormone receptor-positive breast cancer.
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Biomarcadores Tumorais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Animais , Antineoplásicos/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Mitose , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
ABSTRACT: Li, F, Newton, RU, Shi, Y, Sutton, D, and Ding, H. Correlation of eccentric strength, reactive strength, and leg stiffness with running economy in well-trained distance runners. J Strength Cond Res 35(6): 1491-1499, 2021-Neuromuscular characteristics play a critical role in distance running performance; however, their relationship with running economy (RE) remains unclear. The purpose of this study was to evaluate the correlations between 1 repetition maximum (1RM) strength, eccentric strength, reactive strength, leg stiffness, and RE at 12-16 km·h-1 among well-trained male runners. Twenty-eight male collegiate distance runners participated in test sessions on 3 separate days. In the first session, their 1RM squat strength, countermovement jump (CMJ), and drop jump performances were measured. In the second session, the leg press (LP) eccentric and concentric peak force, and leg stiffness (Kleg) were evaluated. In the final session, 12, 14, and 16 km·h-1 RE, blood lactate concentration, and maximum oxygen uptake were measured. There were significant relationships between the LP eccentric peak force, eccentric:concentric peak force ratios (Efl:Cex), RE at speeds of 12, 14, and 16 km·h-1 (r = -0.527 to -0.630; p < 0.01), reactive strength index (r = -0.419 to -0.572; p < 0.05), and Kleg (r = -0.686 to -0.761; p < 0.001) were significantly correlated with RE at 12, 14, and 16 km·h-1. No significant association was found between LP concentric peak force, 1RM squat strength, CMJ, and RE at any speed (p > 0.05). Superior RE among distance runners may be related to greater eccentric strength, elastic energy utilization, and stiffer lower limbs during running but not to maximal muscle strength per se. Coaches should focus on these neuromuscular characteristics to improve running performance.
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Consumo de Oxigênio , Corrida , Humanos , Perna (Membro) , Masculino , Força Muscular , Músculo Esquelético , OxigênioRESUMO
Understanding multi-host pathogen maintenance and transmission dynamics is critical for disease control. However, transmission dynamics remain enigmatic largely because they are difficult to observe directly, particularly in wildlife. Here, we investigate the transmission dynamics of canine parvovirus (CPV) using state-space modelling of 20 years of CPV serology data from domestic dogs and African lions in the Serengeti ecosystem. We show that, although vaccination reduces the probability of infection in dogs, and despite indirect enhancement of population seropositivity as a result of vaccine shedding, the vaccination coverage achieved has been insufficient to prevent CPV from becoming widespread. CPV is maintained by the dog population and has become endemic with approximately 3.5-year cycles and prevalence reaching approximately 80%. While the estimated prevalence in lions is lower, peaks of infection consistently follow those in dogs. Dogs exposed to CPV are also more likely to become infected with a second multi-host pathogen, canine distemper virus. However, vaccination can weaken this coupling, raising questions about the value of monovalent versus polyvalent vaccines against these two pathogens. Our findings highlight the need to consider both pathogen- and host-level community interactions when seeking to understand the dynamics of multi-host pathogens and their implications for conservation, disease surveillance and control programmes.
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Doenças do Cão/transmissão , Leões , Infecções por Parvoviridae/veterinária , Parvovirus Canino/fisiologia , Animais , Teorema de Bayes , Doenças do Cão/epidemiologia , Cães , Ecossistema , Modelos Biológicos , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/transmissão , Prevalência , Estudos Soroepidemiológicos , Tanzânia/epidemiologiaRESUMO
Free living amoebae (FLA), including pathogenic Naegleria fowleri, can colonize and grow within pipe wall biofilms of drinking water distribution systems (DWDSs). Studies on the interactions between various FLA species in biofilms are limited. Understanding the interaction between FLA and the broader biofilm ecology could help better predict DWDS susceptibility to N. fowleri colonization. The aim of this study was to determine if N. fowleri and other FLAs ( Naegleria, Vermamoeba, Willaertia, and Vahlkampfia spp.) cocolonize DWDS biofilm. FLAs commonly isolated from DWDSs ( N. fowleri, V. vermiformis, and N. lovaniensis) were introduced into laboratory-scale biomonitors to determine the impact of these amoebae on N. fowleri's presence and viability. Over 18 months, a single viable amoebae ( N. fowleri, N. lovaniensis, or V. vermiformis) was detected in each biofilm sample, with the exception of N. lovaniensis and N. fowleri, which briefly cocolonized biofilm following their coinoculation. The analysis of biofilm and bulk water samples from operational DWDSs revealed a similar lack of cocolonization with a single FLA detected in 99% ( n = 242) of samples. Interestingly, various Naegleria spp. did colonize the same DWDS locations but at different times. This knowledge furthers the understanding of ecological factors which enable N. fowleri to colonize and survive within operational DWDSs and could aid water utilities to control its occurrence.
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Amoeba , Água Potável , Naegleria fowleri , Biofilmes , EcologiaRESUMO
PURPOSE: We conducted this dosimetric analysis to evaluate the feasibility of a multi-center stereotactic body radiation therapy (SBRT) trial for renal cell carcinoma (RCC) using different SBRT platforms. MATERIALS/METHODS: The computed tomography (CT) simulation images of 10 patients with unilateral RCC previously treated on a Phase 1 trial at Institution 1 were anonymized and shared with Institution 2 after IRB approval. Treatment planning was generated through five different platforms aiming a total dose of 48 Gy in three fractions. These platforms included: Cyberknife and volumetric modulated arc therapy (VMAT) at institution 1, and Cyberknife, VMAT, and pencil beam scanning (PBS) Proton Therapy at institution 2. Dose constraints were based on the Phase 1 approved trial. RESULTS: Compared to Cyberknife, VMAT and PBS plans provided overall an equivalent or superior coverage to the target volume, while limiting dose to the remaining kidney, contralateral kidney, liver, spinal cord, and bowel. CONCLUSION: This dosimetric study supports the feasibility of a multi-center trial for renal SBRT using PBS, VMAT and Cyberknife.
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Enhanced biological phosphorus removal and recovery (EBPR-r) is a biofilm process that makes use of polyphosphate accumulating organisms (PAOs) to remove and recover phosphorus (P) from wastewater. The original process was inefficient, as indicated by the low P-release to carbon (C)-uptake (Prel/Cupt) molar ratio of the biofilm. This study successfully validated a strategy to improve the Prel/Cupt ratio by at least 3-fold. With an unchanged supply of carbon in the recovery stream, an increase in the hydraulic loading in stages I, II and III (7.2, 14.4 and 21.6â¯L, respectively) resulted in a 43% increase in the Prel/Cupt ratio (0.069, 0.076 and 0.103, respectively). The ratio further increased by 150% (from 0.103 to 0.255) when the duration of the P uptake period was increased from 4â¯h (stage III) to 10â¯h (stage IV). Canonical correspondence analysis showed that, correlated to the 3-fold increase in the Prel/Cupt ratio, there was an increase in the abundance of PAOs ("Candidatus Accumulibacter" Clade IIA) and a decrease in the occurrence of glycogen accumulating organisms (GAOs) (family Sinobacteraceae). However, the four stage operation impaired denitrification, resulting in a 5-fold reduction in the Nden/Pupt ratio. The decline in denitrification was consistent with a decrease in the abundance of denitrifiers including denitrifying PAOs (family Comamonadaceae and "Candidatus Accumulibacter" Clade IA). Overall, a strategy to facilitate more efficient use of carbon was validated, enabling a 3-fold carbon saving for P recovery. The new process enabled up to 80% of the wastewater P to be captured in a P-enriched stream (>90â¯mg/L) with a single uptake/release cycle of recovery.
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Reatores Biológicos , Carbono , Fósforo , Desnitrificação , Polifosfatos , Águas ResiduáriasRESUMO
[This corrects the article DOI: 10.1186/s13620-015-0052-3.].
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Inibidores do Fator Xa/efeitos adversos , Neoplasias Hematológicas/tratamento farmacológico , Hemorragia/induzido quimicamente , Tromboembolia Venosa/tratamento farmacológico , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Hematológicas/complicações , Hemorragia/prevenção & controle , Heparina de Baixo Peso Molecular/efeitos adversos , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Ensaios Clínicos Pragmáticos como Assunto , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/mortalidadeRESUMO
In a search for novel small molecule calcium-sensing receptor (CaSR) antagonists as oral bone anabolic agents, we discovered dihydrobenzofuran cyclopropane carboxylic acid derivatives, such as 12f (IC50=27.6nM), are highly potent calcium-sensing receptor antagonists. Studies in rats established that compound 12f stimulates parathyroid hormone (PTH) release in a fast-acting, pulsatile manner.
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Benzofuranos/química , Ciclopropanos/metabolismo , Osteoporose/tratamento farmacológico , Receptores de Detecção de Cálcio/antagonistas & inibidores , Administração Oral , Animais , Benzofuranos/metabolismo , Benzofuranos/farmacocinética , Benzofuranos/uso terapêutico , Ciclopropanos/química , Ciclopropanos/farmacocinética , Ciclopropanos/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Feminino , Meia-Vida , Osteoporose/patologia , Hormônio Paratireóideo/sangue , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Receptores de Detecção de Cálcio/metabolismo , Relação Estrutura-AtividadeRESUMO
Despite aggressive multimodal therapy for pediatric glioblastoma multiforme (GBM), patient survival remains poor. This retrospective review of patients with GBM aims to evaluate the patterns of failure after radiation therapy (RT). The study included 14 pediatric patients treated with RT at the Children's Hospital of Philadelphia from 2007 to 2015. With a median follow-up of 16.9 months, 13 (92.9%) developed recurrent disease. Of recurrences, nine (69.2%) were in-field, three (23.1%) were marginal, and one (7.7%) was distant. The majority of patients treated with adjuvant radiation failed in the region of high-dose RT, indicating the need for improvements in local therapy.
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Glioblastoma/mortalidade , Glioblastoma/radioterapia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/radioterapia , Adolescente , Adulto , Criança , Pré-Escolar , Intervalo Livre de Doença , Glioblastoma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Radioterapia Adjuvante , Estudos Retrospectivos , Falha de Tratamento , Adulto JovemRESUMO
Free-living amoebae, such as Naegleria fowleri, Acanthamoeba spp., and Vermamoeba spp., have been identified as organisms of concern due to their role as hosts for pathogenic bacteria and as agents of human disease. In particular, N. fowleri is known to cause the disease primary amoebic meningoencephalitis (PAM) and can be found in drinking water systems in many countries. Understanding the temporal dynamics in relation to environmental and biological factors is vital for developing management tools for mitigating the risks of PAM. Characterizing drinking water systems in Western Australia with a combination of physical, chemical and biological measurements over the course of a year showed a close association of N. fowleri with free chlorine and distance from treatment over the course of a year. This information can be used to help design optimal management strategies for the control of N. fowleri in drinking-water-distribution systems.
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Água Potável/parasitologia , Naegleria fowleri/isolamento & purificação , Engenharia Sanitária/métodos , Humanos , Fatores de Tempo , Purificação da Água/métodos , Austrália OcidentalRESUMO
BACKGROUND: Tuberculosis caused by Mycobacterium bovis (M. bovis) is very uncommon in horses worldwide. CASE PRESENTATION: In the current study, an eight-year-old male Thoroughbred in good body condition was admitted to the Equine Clinic at the Onderstepoort Veterinary Academic Hospital in 2005 due to bilateral epistaxis accompanied by coughing. Routine examinations were conducted to determine the cause of the condition. Endoscopic examination revealed the major source of the epistaxis as the trachea, whereas thoracic radiography indicated the presence of a primary pulmonary mass. M. bovis was isolated from a broncho-alveolar lavage (BAL) sample collected. The pulmonary mass reduced in size three months later following an oral administration of enrofloxacin (7.5 mg/kg PO SID). Genetic fingerprinting by spoligotyping identified the M. bovis isolate as spoligotype SB0868 strain. This M. bovis strain type was never described previously in South Africa (SA). This is the first case of M. bovis infection in a horse in SA which has been fully documented including clinical findings, isolation and genetic characterisation of the causative pathogen. CONCLUSIONS: This report indicates that horses may contract and harbour M. bovis despite their lower susceptibility compared to other domestic animals. It also suggests that the infection may be more easily contained and eliminated from the host.
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Epistaxe/veterinária , Doenças dos Cavalos/microbiologia , Mycobacterium bovis/genética , Mycobacterium bovis/isolamento & purificação , Tuberculose Pulmonar/veterinária , Animais , Líquido da Lavagem Broncoalveolar/microbiologia , Enrofloxacina , Epistaxe/diagnóstico por imagem , Epistaxe/tratamento farmacológico , Epistaxe/microbiologia , Fluoroquinolonas/uso terapêutico , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Masculino , Tipagem Molecular/veterinária , Mycobacterium bovis/classificação , Radiografia Torácica/veterinária , Resultado do Tratamento , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologiaRESUMO
Naegleria fowleri associated with biofilm and biological demand water (organic matter suspended in water that consumes disinfectants) sourced from operational drinking water distribution systems (DWDSs) had significantly increased resistance to chlorine disinfection. N. fowleri survived intermittent chlorine dosing of 0.6 mg/L for 7 days in a mixed biofilm from field and laboratory-cultured Escherichia coli strains. However, N. fowleri associated with an attached drinking water distribution biofilm survived more than 30 times (20 mg/L for 3 h) the recommended concentration of chlorine for drinking water. N. fowleri showed considerably more resistance to chlorine when associated with a real field biofilm compared to the mixed laboratory biofilm. This increased resistance is likely due to not only the consumption of disinfectants by the biofilm and the reduced disinfectant penetration into the biofilm but also the composition and microbial community of the biofilm itself. The increased diversity of the field biofilm community likely increased N. fowleri's resistance to chlorine disinfection compared to that of the laboratory-cultured biofilm. Previous research has been conducted in only laboratory scale models of DWDSs and laboratory-cultured biofilms. To the best of our knowledge, this is the first study demonstrating how N. fowleri can persist in a field drinking water distribution biofilm despite chlorination.
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Biofilmes/efeitos dos fármacos , Cloro/farmacologia , Desinfetantes/farmacologia , Desinfecção , Água Potável/microbiologia , Naegleria fowleri/efeitos dos fármacos , Microbiologia da Água , Abastecimento de Água , Viabilidade Microbiana/efeitos dos fármacosRESUMO
A biofilm process, termed enhanced biological phosphorus removal and recovery (EBPR-r), was recently developed as a post-denitrification approach to facilitate phosphorus (P) recovery from wastewater. Although simultaneous P uptake and denitrification was achieved despite substantial intrusion of dissolved oxygen (DO >6 mg/L), to what extent DO affects the process was unclear. Hence, in this study a series of batch experiments was conducted to assess the activity of the biofilm under various DO concentrations. The biofilm was first allowed to store acetate (as internal storage) under anaerobic conditions, and was then subjected to various conditions for P uptake (DO: 0-8 mg/L; nitrate: 10 mg-N/L; phosphate: 8 mg-P/L). The results suggest that even at a saturating DO concentration (8 mg/L), the biofilm could take up P and denitrify efficiently (0.70 mmol e(-)/g total solids*h). However, such aerobic denitrification activity was reduced when the biofilm structure was physically disturbed, suggesting that this phenomenon was a consequence of the presence of oxygen gradient across the biofilm. We conclude that when a biofilm system is used, EBPR-r can be effectively operated as a post-denitrification process, even when oxygen intrusion occurs.
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Biofilmes/crescimento & desenvolvimento , Desnitrificação , Nitratos/análise , Oxigênio/química , Fósforo/análise , Purificação da Água/métodos , Aerobiose , Reatores Biológicos/microbiologia , Modelos Teóricos , Nitratos/isolamento & purificação , Fósforo/isolamento & purificação , Águas Residuárias/químicaRESUMO
A 15-year-old Clydesdale cross gelding was investigated and managed over a 2-year period for intermittent collapse. The horse presented initially after an observed episode of collapse at rest, and had a resting tachycardia, elevated Cardiac Troponin I and polycythaemia. Multiple dysrhythmias were detected on telemetric electrocardiography. Vital parameters, cardiac rhythm and red cell count returned to reference range with prolonged rest but further resting syncopal episodes were observed, and due to safety concerns and limited treatment options the horse was euthanased. Post mortem evaluation identified extensive infiltration and replacement of right and left ventricular myocardial fibres with adipose and fibrous tissue, consistent with arrhythmogenic right ventricular cardiomyopathy. This report provides further information regarding the clinical and pathological features of this rarely reported condition.