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In the human pathogen Staphylococcus aureus, branched-chain fatty acids (BCFAs) are the most abundant fatty acids in membrane phospholipids. Strains deficient for BCFAs synthesis experience auxotrophy in laboratory culture and attenuated virulence during infection. Furthermore, the membrane of S. aureus is among the main targets for antibiotic therapy. Therefore, determining the mechanisms involved in BCFAs synthesis is critical to manage S. aureus infections. Here, we report that the overexpression of SAUSA300_2542 (annotated to encode an acyl-CoA synthetase) restores BCFAs synthesis in strains lacking the canonical biosynthetic pathway catalyzed by the branched-chain α-keto acid dehydrogenase (BKDH) complex. We demonstrate that the acyl-CoA synthetase activity of MbcS activates branched-chain carboxylic acids (BCCAs), and is required by S. aureus to utilize the isoleucine derivative 2-methylbutyraldehyde to restore BCFAs synthesis in S. aureus. Based on the ability of some staphylococci to convert branched-chain aldehydes into their respective BCCAs and our findings demonstrating that branched-chain aldehydes are in fact BCFAs precursors, we propose that MbcS promotes the scavenging of exogenous BCCAs and mediates BCFA synthesis via a de novo alternative pathway.
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Coenzima A Ligasas , Ácidos Grasos , Staphylococcus aureus , Aldehídos/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Vías Biosintéticas , Ácidos Carboxílicos/metabolismo , Coenzima A Ligasas/metabolismo , Coenzima A Ligasas/genética , Ácidos Grasos/metabolismo , Ácidos Grasos/biosíntesis , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/enzimologíaRESUMEN
PURPOSE: Currently, there is an increasing tendency to refer only complex aneurysms for microsurgery. The formation of new neurosurgeons dedicated to open vascular neurosurgery becomes challenging in a situation in which complex aneurysms must be dealt with early in the career, raising questions about the safety of the learning curve. METHODS: We analyzed the characteristics and surgical results of the first 300 consecutively treated patients after subarachnoid hemorrhage by a single neurosurgeon. The incidence of surgical complications and clinical outcomes during the learning curve were analyzed, looking for critical periods regarding patient safety. Microsurgical operative times were also studied. RESULTS: A high frequency of wide-necked aneurysms was observed (70.3%), and, as a result, large (> 10 mm), MCA and paraclinoid aneurysms were overrepresented. A statistically significant correlation between surgical experience and clinical outcomes was observed, with progressive surgical experience resulting in a lower incidence of unfavorable outcomes. We also observed a higher frequency of major surgical complications, unfavorable clinical outcomes, and lower complete occlusion rates among the first 40 patients. Microsurgical operative times progressively and significantly decreased during the learning curve. CONCLUSIONS: We observed a high prevalence of wide-necked aneurysms. Young neurosurgeons must be trained and prepared to deal with these aneurysms early in their careers. Although we observed a decrease in unfavorable results with cumulative surgical experience, the first 40 cases were associated with higher rates of major surgical complications, worse clinical outcomes, and lower complete occlusion rates, indicating that this period may be more critical to patient safety.
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Aneurisma Roto , Procedimientos Endovasculares , Aneurisma Intracraneal , Hemorragia Subaracnoidea , Aneurisma Roto/etiología , Procedimientos Endovasculares/efectos adversos , Humanos , Aneurisma Intracraneal/complicaciones , Curva de Aprendizaje , Microcirugia/efectos adversos , Microcirugia/métodos , Estudios Retrospectivos , Hemorragia Subaracnoidea/complicaciones , Resultado del TratamientoRESUMEN
We examined the effects of including sunflower cake (SC) associated with an enzyme complex (EC) in the diet of meat quails on nutrient metabolism, performance, carcass characteristics, bone parameters and economic viability. In total, 432 meat quails (7 to 42 days old) were assigned to six treatments in a completely randomised design with 6 replicates with 12 birds each. A 2 × 3 factorial arrangement was adopted (two levels of SC: 10 and 20%; three diet formulation strategies: normal, reduction in the nutrient and energy matrix considering the enzymatic contribution and reduced diet with EC). No interaction effect was observed. The increased levels of SC from 10% to 20% promoted in decrease in the metabolisability coefficients of dry matter and gross energy and in the value of AMEn and increased relative weight of gizzard. The addition of EC in diets containing SC allows a better metabolization of nitrogen and energy, equalize to the normal diet. The best breast yield was obtained in the birds fed the reduced diet with EC, in relation to normal diet. The reduced diet and the reduced diet with EC provided the lowest cost of food and the best economic efficiency index. Up to 20% of the sunflower cake can be included in the diet of cut quail, with or without enzyme supplementation. However, the use of the enzyme complex composed of carbohydrases, proteases and phytase can favor the metabolization of nitrogen and energy from the diet containing sunflower cake.
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Fenómenos Fisiológicos Nutricionales de los Animales , Helianthus , Codorniz , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Suplementos Dietéticos/análisis , Carne/análisis , Nitrógeno/metabolismo , Semillas , Aumento de PesoRESUMEN
Synthetic antioxidants (e.g.butylhydroxytoluene, BHT) are routinely used for to restrict oxidative processes of meat products, but they are implicated as harmful to the health of humans. Therefore natural alternatives, such as plant antioxidants, have been sought as replacements. Plant antioxidants when added to the diet can be incorporated into meat and reduce the need for the addition of synthetic antioxidants during processing. The objective of this study was to evaluate the effects of ethanol extracts of mango seeds (EEMS) in the diet of pigs on qualitative parameters and total antioxidant capacity of mortadella produced from these animals. Thirty-two pigs with an average 60 days of age were distributed among four treatments: control=no antioxidant; BHT=200ppm BHT; EEMS200=200ppm of EEMS and EEMS400=400ppm of EEMS. At 145 days of age the animals were slaughtered and loin was removed for the preparation of mortadella, which was analyzed during 90 days of storage at 4°C. A higher content of polyphenolic compounds and, total antioxidant capacity in mortadellas processed with meat of animals which consumed the EEMS400 ration after 60 and 90 days of storage was observed. EEMS polyphenolic antioxidants incorporated into pork through the diet results in an increase of total antioxidant capacity in the processed product.
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Mangifera , Carne de Cerdo , Carne Roja , Animales , Antioxidantes , Dieta , Etanol , Oxidación-Reducción , Extractos Vegetales/farmacología , Semillas , PorcinosRESUMEN
Marine sponges has been a large reservoir of microbial diversity, with the presence of many species specific populations as well as producing biologically active compounds, which has attracted great biotechnological interest. In order to verify the influence of the environment in the composition of the bacterial community present in marine sponges and biotechnological potential of bacteria isolated from these organisms, three species of sponges and the waters surrounding them were collected in different beaches of Rio de Janeiro, Brazil. The profile of the bacterial community present in sponges and water was obtained by PCR-DGGE technique and the biotechnological potential of the strains isolated by producing amylase, cellulase, protease and biosurfactants. The results showed that despite the influence of the environment in the composition of the microbial community, studied marine sponges shown to have specific bacterial populations, with some, showing potential in the production of substances of biotechnological applications.
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Bacterias/aislamiento & purificación , Poríferos/microbiología , Animales , Bacterias/clasificación , Biotecnología , Brasil , Biología Marina , Reacción en Cadena de la Polimerasa , Poríferos/enzimologíaRESUMEN
LCA has evolved from its origins in energy analysis in the 1960s and 70s into a wide ranging tool used to determine impacts of products or systems over several environmental and resource issues. The approach has become more prevalent in research, industry and policy. Its use continues to expand as it seeks to encompass impacts as diverse as resource accounting and social well being. Carbon policy for bioenergy has driven many of these changes. Enabling assessment of complex issues over a life cycle basis is beneficial, but the process is sometimes difficult. LCA's use in framing is increasingly complex and more uncertain, and in some cases, irreconcilable. The charged environment surrounding biofuels and bioenergy exacerbates all of these. Reaching its full potential to help guide difficult policy discussions and emerging research involves successfully managing LCA's transition from attributional to consequential and from retrospective to prospective. This paper examines LCA's on-going evolution and its use within bioenergy deployment. The management of methodological growth in the context of the unique challenges associated with bioenergy and biofuels is explored. Changes seen in bioenergy LCA will bleed into other LCA arenas, especially where it is important that a sustainable solution is chosen.
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PURPOSE: Bioenergy is increasingly used to help meet greenhouse gas (GHG) and renewable energy targets. However, bioenergy's sustainability has been questioned, resulting in increasing use of life cycle assessment (LCA). Bioenergy systems are global and complex, and market forces can result in significant changes, relevant to LCA and policy. The goal of this paper is to illustrate the complexities associated with LCA, with particular focus on bioenergy and associated policy development, so that its use can more effectively inform policymakers. METHODS: The review is based on the results from a series of workshops focused on bioenergy life cycle assessment. Expert submissions were compiled and categorized within the first two workshops. Over 100 issues emerged. Accounting for redundancies and close similarities in the list, this reduced to around 60 challenges, many of which are deeply interrelated. Some of these issues were then explored further at a policy-facing workshop in London, UK. The authors applied a rigorous approach to categorize the challenges identified to be at the intersection of biofuels/bioenergy LCA and policy. RESULTS AND DISCUSSION: The credibility of LCA is core to its use in policy. Even LCAs that comply with ISO standards and policy and regulatory instruments leave a great deal of scope for interpretation and flexibility. Within the bioenergy sector, this has led to frustration and at times a lack of obvious direction. This paper identifies the main challenge clusters: overarching issues, application and practice and value and ethical judgments. Many of these are reflective of the transition from application of LCA to assess individual products or systems to the wider approach that is becoming more common. Uncertainty in impact assessment strongly influences planning and compliance due to challenges in assigning accountability, and communicating the inherent complexity and uncertainty within bioenergy is becoming of greater importance. CONCLUSIONS: The emergence of LCA in bioenergy governance is particularly significant because other sectors are likely to transition to similar governance models. LCA is being stretched to accommodate complex and broad policy-relevant questions, seeking to incorporate externalities that have major implications for long-term sustainability. As policy increasingly relies on LCA, the strains placed on the methodology are becoming both clearer and impedimentary. The implications for energy policy, and in particular bioenergy, are large.
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In July 2014, as the Ebola virus disease (Ebola) epidemic expanded in Guinea, Liberia, and Sierra Leone, an air traveler brought Ebola to Nigeria and two American health care workers in West Africa were diagnosed with Ebola and later medically evacuated to a U.S. hospital. New York City (NYC) is a frequent port of entry for travelers from West Africa, a home to communities of West African immigrants who travel back to their home countries, and a home to health care workers who travel to West Africa to treat Ebola patients. Ongoing transmission of Ebolavirus in West Africa could result in an infected person arriving in NYC. The announcement on September 30 of an Ebola case diagnosed in Texas in a person who had recently arrived from an Ebola-affected country further reinforced the need in NYC for local preparedness for Ebola.
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Epidemias/prevención & control , Fiebre Hemorrágica Ebola/prevención & control , Vigilancia de la Población , Fiebre Hemorrágica Ebola/epidemiología , Humanos , Ciudad de Nueva York/epidemiologíaRESUMEN
Schistosomiasis is a neglected tropical disease caused by blood flukes of the genus Schistosoma. This disease control has been widely made by praziquantel-reference drug, but resistance to this drug has already been found. There has been the finding of an imidazole alkaloid in jaborandi leaves-epiisopiloturine, which has known activity against adult, young and egg forms of Schistosoma mansoni. This alkaloid is an apolar molecule with difficult solubility; therefore, the liposomal structure of epiisopiloturine was proposed. Liposomes are carrying structures of drugs that may enhance solubility of compounds such as epiisopiloturine. In this work, we report in vitro epiisopiloturine-loaded liposomes effect formed by different concentrations of lipids 9:1 (weight ratio) dipalmitoylphosphatidylcholine:cholesterol and 8:2 (weight ratio) dipalmitoylphosphatidylcholine:cholesterol. Results have showed that epiisopiloturine extraction and isolation have been successful through high-performance liquid chromatography-HPLC and its purity confirmed through mass spectrometry has showed 287 Da molecular mass. Formulations from 9:1 DPPC:cholesterol and 8:2 DPPC:cholesterol with loaded EPI (300 microg/ml) have killed parasites at 100% after incubation 96 h and 120 h, respectively. Confocal microscopy employed to observe morphological alterations in the tegument of adult form of Schistosoma mansoni. Details from interaction, between epiisopiloturine and liposome, have been achieved by semi-empirical AM1 calculations, which have showed that epiisopiloturine inside is more stable than the outside form, at least 10 kcal. This is first time that schistosomicidal activity has been reported for epiisopiloturine-loaded into liposome.
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4-Butirolactona/análogos & derivados , Imidazoles/síntesis química , Imidazoles/farmacología , Liposomas/química , Nanocápsulas/administración & dosificación , Schistosoma mansoni/efectos de los fármacos , Schistosoma mansoni/fisiología , 4-Butirolactona/síntesis química , 4-Butirolactona/farmacología , Animales , Antihelmínticos/síntesis química , Antihelmínticos/farmacología , Ensayo de Materiales , Nanocápsulas/química , Schistosoma mansoni/anatomía & histología , Resultado del TratamientoRESUMEN
Wellbeing has emerged as a central, if not defining, feature of contemporary social life. Yet, despite its global significance spanning the political, social and economic spectrum, there is a remarkable lack of agreement regarding the conceptualization, definition or operationalisation of wellbeing nor any clear evidence of its success as an instrument of policy. This essay explores the contested terrain of wellbeing by examining the concept in relation to emerging politics, complexities and contradictions. More specifically, the essay: (1) briefly describes the historical origins and development of wellbeing; (2) discusses how it has been reconceptualised within the context of neoliberalism; and, (3) outlines a research agenda offering three ways to investigate wellbeing including: (a) as a wicked problem; (b) as part of the process of "wellbeing washing" within state and other institutional structures and policies; and, (c) in relation to alternative futures, which might encourage us to reimagine or jettison the term altogether.
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Mastigimas anjosi is an important pest of Cedrela fissilis in the southeastern and southern regions of Brazil. The objective of the present study was to investigate the effect of the temperature, relative humidity, rainfall and natural enemies on the flight activity of adults and the movement of M. anjosi nymphs, with two sampling methods, yellow sticky traps and direct collections on the leaves of C. fissilis trees. The sex ratio of this pest was also assessed. The number of M. anjosi individuals was negatively correlated with the minimum and maximum temperatures, with a population peak in late May and early June 2017. The numbers of individuals of this psyllid was positively correlated with the relative humidity and rainfall. Larvae and adults of Cycloneda sanguinea, Hippodamia convergens adults and Atopozelus opsimus nymphs and adults preyed upon M. anjosi adults and nymphs on C. fissilis leaves in the field. Mastigimas anjosi sex ratio was 0.46. Information about sampling methods of M. anjosi and its natural enemies is presented and can contribute to the integrated management of this pest in the field.
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This article addresses the interactions of the synthetic antimicrobial peptide dermaseptin 01 (GLWSTIKQKGKEAAIAAA- KAAGQAALGAL-NH(2) , DS 01) with phospholipid (PL) monolayers comprising (i) a lipid-rich extract of Leishmania amazonensis (LRE-La), (ii) zwitterionic PL (dipalmitoylphosphatidylcholine, DPPC), and (iii) negatively charged PL (dipalmitoylphosphatidylglycerol, DPPG). The degree of interaction of DS 01 with the different biomembrane models was quantified from equilibrium and dynamic liquid-air interface parameters. At low peptide concentrations, interactions between DS 01 and zwitterionic PL, as well as with the LRE-La monolayers were very weak, whereas with negatively charged PLs the interactions were stronger. For peptide concentrations above 1 µg/ml, a considerable expansion of negatively charged monolayers occurred. In the case of DPPC, it was possible to return to the original lipid area in the condensed phase, suggesting that the peptide was expelled from the monolayer. However, in the case of DPPG, the average area per lipid molecule in the presence of DS 01 was higher than pure PLs even at high surface pressures, suggesting that at least part of DS 01 remained incorporated in the monolayer. For the LRE-La monolayers, DS 01 also remained in the monolayer. This is the first report on the antiparasitic activity of AMPs using Langmuir monolayers of a natural lipid extract from L. amazonensis.
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Proteínas Anfibias/química , Péptidos Catiónicos Antimicrobianos/química , Antiprotozoarios/química , Leishmania/efectos de los fármacos , Fosfolípidos/metabolismo , Secuencia de Aminoácidos , Proteínas Anfibias/farmacocinética , Antiinfecciosos/química , Péptidos Catiónicos Antimicrobianos/farmacocinética , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Leishmania/metabolismo , Membranas Artificiales , Modelos BiológicosRESUMEN
Recent advances in the control of molecular engineering architectures have allowed unprecedented ability of molecular recognition in biosensing, with a promising impact for clinical diagnosis and environment control. The availability of large amounts of data from electrical, optical, or electrochemical measurements requires, however, sophisticated data treatment in order to optimize sensing performance. In this study, we show how an information visualization system based on projections, referred to as Projection Explorer (PEx), can be used to achieve high performance for biosensors made with nanostructured films containing immobilized antigens. As a proof of concept, various visualizations were obtained with impedance spectroscopy data from an array of sensors whose electrical response could be specific toward a given antibody (analyte) owing to molecular recognition processes. In addition to discussing the distinct methods for projection and normalization of the data, we demonstrate that an excellent distinction can be made between real samples tested positive for Chagas disease and Leishmaniasis, which could not be achieved with conventional statistical methods. Such high performance probably arose from the possibility of treating the data in the whole frequency range. Through a systematic analysis, it was inferred that Sammon's mapping with standardization to normalize the data gives the best results, where distinction could be made of blood serum samples containing 10(-7) mg/mL of the antibody. The method inherent in PEx and the procedures for analyzing the impedance data are entirely generic and can be extended to optimize any type of sensor or biosensor.
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Técnicas Biosensibles/métodos , Leishmaniasis/diagnóstico , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos , Enfermedad de Chagas/diagnóstico , Impedancia Eléctrica , NanoestructurasRESUMEN
In July 1991, Sports Illustrated published a special issue featuring two articles that prognosticated about what sport would look like 10 years later. As the world entered the 21st century, Sports Illustrated writers, Oscar Johnson and Ron Fimrite, offered their visions of sport in the year 2001. Their analysis highlighted how a range of economic, social and technological changes in society would impact on how sport is structured, produced and consumed, but also offered insights into the future of the major professional sport leagues in North America. It has been 30 years since they publicised their views and, while technology continues to impact sport, the Covid-19 pandemic has forced the world to pause and to consider a range of deep, soul-searching questions about the nature of society, including sport. Against this background, we consider the opportunities and challenges for sport in the 21st century. The paper is divided into three sections including: (1) a reflection on the meaning, value and significance of sport including its privileged position in society, or what we refer to as "sporting exceptionalism"; (2) a brief overview of a case study that illustrates the challenges facing the global business of sport; and, (3) a framework for conceptualising alternative futures in the global business of sport, drawing on examples from women's sport.
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BACKGROUND: Heterotrophic single-cell oils (SCOs) are one potential replacement to lipid-derived biofuels sourced from first-generation crops such as palm oil. However, despite a large experimental research effort in this area, there are only a handful of techno-economic modelling publications. As such, there is little understanding of whether SCOs are, or could ever be, a potential competitive replacement. To help address this question, we designed a detailed model that coupled a hypothetical heterotroph (using the very best possible biological lipid production) with the largest and most efficient chemical plant design possible. RESULTS: Our base case gave a lipid selling price of $1.81/kg for ~ 8,000 tonnes/year production, that could be reduced to $1.20/kg on increasing production to ~ 48,000 tonnes of lipid a year. A range of scenarios to further reduce this cost were then assessed, including using a thermotolerant strain (reducing the cost from $1.20 to $1.15/kg), zero-cost electricity ($ 1.12/kg), using non-sterile conditions ($1.19/kg), wet extraction of lipids ($1.16/kg), continuous production of extracellular lipid ($0.99/kg) and selling the whole yeast cell, including recovering value for the protein and carbohydrate ($0.81/kg). If co-products were produced alongside the lipid then the price could be effectively reduced to $0, depending on the amount of carbon funnelled away from lipid production, as long as the co-product could be sold in excess of $1/kg. CONCLUSIONS: The model presented here represents an ideal case that which while not achievable in reality, importantly would not be able to be improved on, irrespective of the scientific advances in this area. From the scenarios explored, it is possible to produce lower cost SCOs, but research must start to be applied in three key areas, firstly designing products where the whole cell is used. Secondly, further work on the product systems that produce lipids extracellularly in a continuous processing methodology or finally that create an effective biorefinery designed to produce a low molecular weight, bulk chemical, alongside the lipid. All other research areas will only ever give incremental gains rather than leading towards an economically competitive, sustainable, microbial oil.
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Monitoring global biodiversity from space through remotely sensing geospatial patterns has high potential to add to our knowledge acquired by field observation. Although a framework of essential biodiversity variables (EBVs) is emerging for monitoring biodiversity, its poor alignment with remote sensing products hinders interpolation between field observations. This study compiles a comprehensive, prioritized list of remote sensing biodiversity products that can further improve the monitoring of geospatial biodiversity patterns, enhancing the EBV framework and its applicability. The ecosystem structure and ecosystem function EBV classes, which capture the biological effects of disturbance as well as habitat structure, are shown by an expert review process to be the most relevant, feasible, accurate and mature for direct monitoring of biodiversity from satellites. Biodiversity products that require satellite remote sensing of a finer resolution that is still under development are given lower priority (for example, for the EBV class species traits). Some EBVs are not directly measurable by remote sensing from space, specifically the EBV class genetic composition. Linking remote sensing products to EBVs will accelerate product generation, improving reporting on the state of biodiversity from local to global scales.
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Benchmarking , Ecosistema , BiodiversidadRESUMEN
BACKGROUND. When the 2009 H1N1 influenza A virus emerged in the United States, epidemiologic and clinical information about severe and fatal cases was limited. We report the first 47 fatal cases of 2009 H1N1 influenza in New York City. METHODS. The New York City Department of Health and Mental Hygiene conducted enhanced surveillance for hospitalizations and deaths associated with 2009 H1N1 influenza A virus. We collected basic demographic and clinical information for all patients who died and compared abstracted data from medical records for a sample of hospitalized patients who died and hospitalized patients who survived. RESULTS. From 24 April through 1 July 2009, 47 confirmed fatal cases of 2009 H1N1 influenza were reported to the New York City Department of Health and Mental Hygiene. Most decedents (60%) were ages 18-49 years, and only 4% were aged 65 years. Many (79%) had underlying risk conditions for severe seasonal influenza, and 58% were obese according to their body mass index. Thirteen (28%) had evidence of invasive bacterial coinfection. Approximately 50% of the decedents had developed acute respiratory distress syndrome. Among all hospitalized patients, decedents had presented for hospitalization later (median, 3 vs 2 days after illness onset; P < .05) and received oseltamivir later (median, 6.5 vs 3 days; P < .01) than surviving patients. Hospitalized patients who died were less likely to have received oseltamivir within 2 days of hospitalization than hospitalized patients who survived (61% vs 96%; P < .01). CONCLUSIONS. With community-wide transmission of 2009 H1N1 influenza A virus, timely medical care and antiviral therapy should be considered for patients with severe influenza-like illness or with underlying risk conditions for complications from influenza.
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Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/mortalidad , Gripe Humana/virología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Comorbilidad , Femenino , Hospitalización , Humanos , Lactante , Masculino , Persona de Mediana Edad , Ciudad de Nueva York/epidemiología , Obesidad/complicaciones , Neumonía Bacteriana/complicaciones , Síndrome de Dificultad Respiratoria/epidemiología , Factores de Riesgo , Adulto JovenRESUMEN
The need for reliable, fast diagnostics is closely linked to the need for safe, effective treatment of the so-called "neglected" diseases. The list of diseases with no field-adapted diagnostic tools includes leishmaniasis, shigella, typhoid, and bacterial meningitis. Leishmaniasis, in particular, is a parasitic disease caused by Leishmania spp. transmitted by infected phlebotomine sandfly, which remains a public health concern in developing countries with ca. 12 million people infected and 350 million at risk of infection. Despite several attempts, methods for diagnosis are still noneffective, especially with regard to specificity due to false positives with Chagas' disease caused by Trypanosoma cruzi . Accepted golden standards for detecting leishmaniasis involve isolation of parasites either microscopically, or by culture, and in both methods specimens are obtained by invasive means. Here, we show that efficient distinction between cutaneous leishmaniasis and Chagas' disease can be obtained with a low-cost biosensor system made with nanostructured films containing specific Leishmania amazonensis and T. cruzi antigens and employing impedance spectroscopy as the detection method. This unprecedented selectivity was afforded by antigen-antibody molecular recognition processes inherent in the detection with the immobilized antigens, and by statistically correlating the electrical impedance data, which allowed distinction between real samples that tested positive for Chagas' disease and leishmaniasis. Distinction could be made of blood serum samples containing 10(-5) mg/mL of the antibody solution in a few minutes. The methods used here are generic and can be extended to any type of biosensor, which is important for an effective diagnosis of many other diseases.
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Técnicas Biosensibles/métodos , Leishmaniasis/diagnóstico , Animales , Anticuerpos/sangre , Antígenos/química , Antígenos/inmunología , Enfermedad de Chagas/diagnóstico , Dendrímeros/química , Técnicas Electroquímicas/métodos , Electrodos , Proteínas Inmovilizadas/química , Proteínas Inmovilizadas/inmunología , Leishmania/inmunología , Ratones , Nanoestructuras/química , Enfermedades Desatendidas/diagnóstico , Análisis de Componente Principal , Trypanosoma cruzi/inmunologíaRESUMEN
This study aimed to evaluate the incidence of black bone syndrome (BBS) in broiler chickens fed with ethanolic extract of mango seed (EEMS). A total of 504 one-day-old male broilers were used in a completely randomised design assigned with 7 experimental diets and 6 replicates of 12 broilers per experimental plot. The experimental diets consisted of: diet without addition of synthetic antioxidant; diet with addition of synthetic antioxidant (200 ppm); and 5 levels of EEMS: 200 ppm, 400 ppm, 600 ppm, 800 ppm, and 1,000 ppm. Two methods of cooking (roasted and boiled) were used to prepare thigh samples. According to the results, the diets did not significantly influence the performance of the broilers. BBS incidence was higher in broilers fed a diet without antioxidants and was reduced with EEMS dietary inclusion, with the lowest incidence occurring with the inclusion of 1,000 ppm. The synthetic antioxidant butylated hydroxytoluene in the diet promoted a significantly higher BBS incidence than that obtained with 800 and 1,000 ppm EEMS and did not differ from the other diets. Of the cooking methods, a higher BBS incidence was observed for the boiled method. For the meat coloration and bone parameters, there were no significant interactions between the factors, diets and cooking methods. There was a linear reduction in the darkening score and linear increase in the luminosity (L∗) of the meat with increasing EEMS in the diet. With regard to the cooking method, the boiled thighs had lower luminosity (L∗), higher parameter a∗, and lower parameter b∗ values because of more pronounced meat darkening. The roasted bones were less heavy, dense, and flexible. A negative correlation was observed between the degree of darkening of the meat that characterizes the BBS with the luminosity (L∗) and intensity of yellow. We concluded that the addition of EEMS contributes to a reduced darkening of meat that characterises the BBS and recommend the dietary inclusion of 1,000-ppm EEMS.
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Enfermedades Óseas/veterinaria , Pollos , Culinaria , Mangifera/química , Carne/análisis , Extractos Vegetales/efectos adversos , Enfermedades de las Aves de Corral/patología , Animales , Enfermedades Óseas/inducido químicamente , Enfermedades Óseas/patología , Culinaria/métodos , Relación Dosis-Respuesta a Droga , Masculino , Extractos Vegetales/química , Enfermedades de las Aves de Corral/inducido químicamente , Semillas/químicaRESUMEN
Staphylococcus epidermidis is one of the leading causes of bloodstream infections, particularly in premature neonates, and biofilm formation is a major virulence factor. We characterized biofilm formation by 50â¯S. epidermidis neonatal isolates under osmotic stress and evaluated the expression of biofilm-associated genes. Phenotypical analyses of biofilm production were performed in culture medium with or without addition of NaCl or glucose. In control medium (no additions), most isolates (84%) were nonproducers or weak biofilm producers. Growth in NaCl-containing medium increased the number of moderate/strong producers, and this increase was even greater in medium containing glucose. Most of the protein-enriched biofilms (60%) could be observed only during growth in glucose, whereas 50% of the polysaccharide-enriched biofilms were observed during growth in NaCl. Studies that evaluate the conditions used to characterize biofilm production are important to help us understand the dynamics of this important virulence factor in S. epidermidis and their impact on neonatal infections.