Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
1.
Zoo Biol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934616

RESUMO

Zoological institutions frequently engage in indirect conservation activities as global conservation targets suggest a need for raising public awareness and engagement in biodiversity conservation. However, research suggests that while members of the public are typically aware of general conservation issues, they are often uncertain of simple and practical actions they take that will be impactful. In light of current conservation goals and targets, and the need for social science research to address the environmental learning and behavior change gap, this study builds upon prior action-based environmental education research and tests the efficacy of ex situ environmental education in supporting in situ conservation. Zoos typically employ flagship species to center their conservation messaging due to the purported draw of charismatic species. Using outreach videos with a dialogic-based narrative approach, we evaluated the efficacy of different flagships for conservation, comparing both species-focused versus generic conservation messaging and charismatic versus less charismatic species ambassadors. We found that zoo conservation outreach videos using dialogic-based narrative approaches were equally impactful regardless of the level of focus (i.e., species vs. broader biodiversity) or charisma level of the focal taxa.

2.
Retina ; 43(1): 25-33, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542081

RESUMO

PURPOSE: AR-1105 is a novel biodegradable sustained-release dexamethasone implant designed to deliver 6-month durability. This Phase 2 study evaluated two AR-1105 formulations with different release profiles in patients with macular edema due to retinal vein occlusion. METHODS: Patients received a single intravitreal injection with 340 µg dexamethasone. In the initial phase, five patients received clinical formulation (CF) 1. In the randomized phase, 44 patients were randomized 1:1 to CF1 or CF2. The follow-up was 6 months. Patients had vision loss due to macular edema diagnosed ≥9 (central retinal vein occlusion) or ≥12 months (branch retinal vein occlusion) before screening, and could be treatment-naive or -experienced (if received prior steroids, must have demonstrated response). RESULTS: Both formulations improved vision and reduced retinal thickening from baseline across all visits. At Month 6, mean changes in best-corrected visual acuity were +4.3 and +8.0 letters, and mean changes in central subfield thickness were -93 µm and -211 µm in CF1 and CF2 randomized patients, respectively. Most common adverse events were reduced visual acuity, worsening macular edema, conjunctival hemorrhage, and increased intraocular pressure. No patients required surgery or laser for intraocular pressure control. CONCLUSION: Both formulations were well tolerated and demonstrated clinically meaningful and sustained improvements in vision and retinal thickening in patients with retinal vein occlusion with longstanding edema.


Assuntos
Edema Macular , Oclusão da Veia Retiniana , Humanos , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/diagnóstico , Oclusão da Veia Retiniana/tratamento farmacológico , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Dexametasona , Glucocorticoides , Resultado do Tratamento , Implantes de Medicamento , Tomografia de Coerência Óptica , Injeções Intravítreas
3.
Retina ; 41(1): 144-155, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32134802

RESUMO

PURPOSE: To evaluate the safety and efficacy of Brimonidine Drug Delivery System (Brimo DDS), a biodegradable intravitreal implant, in the treatment of geographic atrophy (GA) secondary to age-related macular degeneration. METHODS: Phase 2, randomized, multicenter, double-masked, 24-month study. Study eyes were treated (Day 1; Month 6 retreatment) with Brimo DDS 132 µg (n = 49), Brimo DDS 264 µg (n = 41), or sham procedure (n = 23). The primary timepoint for efficacy analysis was Month 12. RESULTS: Mean GA area growth at Month 12 was 1.78 mm2, 1.59 mm2, and 2.19 mm2 in the Brimo DDS 132 µg, 264 µg, and sham groups, respectively. Geographic atrophy area growth was consistently smaller with Brimo DDS 132 and 264 µg than sham; between-group differences were significant (P ≤ 0.032) at Month 3. In patients with baseline lesion area ≥6 mm2 (two-thirds of patients), GA lesion area and effective radius growth was reduced with Brimo DDS 132 and 264 µg at Month 12 (P ≤ 0.050 vs. sham). Treatment-related adverse events were usually injection procedure-related. CONCLUSION: Brimo DDS demonstrated a favorable safety profile and reduced GA lesion area growth at Month 3. Lesion growth at Month 12 was reduced in patients with baseline GA lesion area ≥6 mm2. The results support Phase 3 development.


Assuntos
Tartarato de Brimonidina/administração & dosagem , Atrofia Geográfica/tratamento farmacológico , Degeneração Macular/tratamento farmacológico , Acuidade Visual , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Sistemas de Liberação de Medicamentos , Feminino , Angiofluoresceinografia/métodos , Seguimentos , Fundo de Olho , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/etiologia , Humanos , Injeções Intravítreas , Degeneração Macular/complicações , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
4.
Zoo Biol ; 40(1): 65-75, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33043534

RESUMO

The vast number of species threatened with extinction, coupled with the limited resources to support them, results in the need to prioritize species for conservation action. Similarly, zoo collection managers must prioritize species for inclusion at their institutions, which are also limited by space and resources. While conservation status is one factor considered by zoos, weight is also given to qualitative features and practical considerations when evaluating the fit of different species. Resultantly, the species prioritized by zoos have limited overlap with those prioritized for conservation. Several recent studies have highlighted that the majority of species maintained in zoos are ranked globally as least concern. Given the centrality of conservation to the modern mission of zoos, there is value in identifying clear connections between non-threatened species in zoos and the roles they can play in conservation. Surrogate species approaches have been used in many instances to facilitate indirect conservation, and several distinctive types of surrogacy have been formally described. The aim of this study is to define a novel form of species surrogacy (i.e., "proxy species") that draws utility from non-threatened species maintained in zoos. A proxy species is here defined as a non-threatened species managed ex situ that can be used as a flagship for a related threatened species that is morphologically similar but not otherwise represented in zoos. The benefits of this approach and opportunities for its application are here reviewed. This concept will provide opportunities to enhance the value of pre-existing zoo collections, and ultimately, support conservation objectives.


Assuntos
Animais de Zoológico , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Animais
5.
Zoo Biol ; 39(4): 257-262, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32196733

RESUMO

Using molecular genetic information to guide population management can improve the sustainability of species in captivity. However, empirical population genetics has not been commonly applied to species management programs in zoos. One limitation may be the availability of genetic resources (e.g., markers, primers, etc.) for species held in zoos. To assess the extent to which species held in zoos have been studied using population genetics in the wild, we conducted a systematic literature review of close to 8,000 papers. We synthesized information on the availability and scale of population genetics studies across amphibian, bird, mammal, and reptile species held in zoos, and discussed their potential for informing ex situ management. We found that more than half of the species in zoos (52%) already have some genetic markers described in the literature specific for them, or a congeneric species, that could be further developed to aid the management of zoo populations, and the accumulation of these resources has been steady over the past decades. Furthermore, the proportion of species with genetic resources is even higher (62%) for species that are being managed through a formal breeding program in zoos. Our study provides encouraging results for captive program managers interested in integrating population genetics into ex situ management strategies.


Assuntos
Anfíbios/genética , Aves/genética , Mamíferos/genética , Répteis/genética , Animais , Animais de Zoológico , Conservação dos Recursos Naturais/métodos
6.
Chembiochem ; 15(3): 466-71, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24449436

RESUMO

Mono- and disaccharide-functionalised conjugates of the fluoroquinolone antibiotic ciprofloxacin have been synthesised and used as chemical probes of the bacterial uptake of glycosylated ciprofloxacin. Their antimicrobial activities against a panel of clinically relevant bacteria were determined: the ability of these conjugates to inhibit their target DNA gyrase and to be transported into the bacteria was assessed by using in vivo and in vitro assays. The data suggest a lack of active uptake through sugar transporters and that although the addition of monosaccharides is compatible with the inhibition of DNA gyrase, the addition of a disaccharide results in a significant decrease in antimicrobial activity.


Assuntos
Antibacterianos/química , Ciprofloxacina/química , Glicoconjugados/química , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , DNA Girase/química , DNA Girase/metabolismo , Dissacarídeos/química , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Glicoconjugados/síntese química , Glicoconjugados/farmacologia , Glicosilação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Monossacarídeos/química
7.
Bioorg Med Chem ; 22(16): 4499-505, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24794750

RESUMO

A series of structurally related citric acid-ciprofloxacin conjugates was synthesised to investigate the influence of the linker between citric acid and ciprofloxacin on antibacterial activities. Minimum inhibitory concentrations (MICs) were determined against a panel of reference strains and clinical isolates of bacteria associated with infection in humans and correlated with the DNA gyrase inhibitory activity. The observed trend was rationalised by computational modelling.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Ácido Cítrico/química , Desenho de Fármacos , Inibidores da Topoisomerase II/farmacologia , Antibacterianos/síntese química , Bactérias/efeitos dos fármacos , Ácido Cítrico/farmacologia , DNA Girase/metabolismo , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química
8.
Org Biomol Chem ; 11(21): 3461-8, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23575952

RESUMO

A series of fluoroquinolone conjugates was synthesised by linking the carboxylic acid functionality of the carboxylate-type siderophore staphyloferrin A and its derivatives to the piperazinyl nitrogen of ciprofloxacin and norfloxacin via amide bond formation. Four siderophore-drug conjugates were screened against a panel of bacteria associated with infection in humans. Whilst no activity was found against ciprofloxacin- or norfloxacin-resistant bacteria, one of the conjugates retained antibacterial activity against fluoroquinolone-susceptible strains although the structure of its lysine-based siderophore component differs from that of the natural siderophore staphyloferrin A. In contrast, three ornithine-based siderophore conjugates showed significantly reduced activity against strains that are susceptible to their respective parent fluoroquinolones, regardless of the type of fluoroquinolone attached or chirality at the ornithine Cα-atom. The loss of potency observed for the (R)- and (S)-ornithine-based ciprofloxacin conjugates correlates with their reduced inhibitory activity against the target enzyme DNA gyrase.


Assuntos
Antibacterianos/química , Citratos/química , Fluoroquinolonas/química , Ornitina/análogos & derivados , Sideróforos/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ácidos Carboxílicos/química , Fluoroquinolonas/síntese química , Fluoroquinolonas/farmacologia , Humanos , Modelos Moleculares , Ornitina/química
9.
Genome ; 53(12): 1103-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21164542

RESUMO

Nuclear mitochondrial pseudogenes, or "numts", are nonfunctional copies of mitochondrial genes that have been translocated to the nuclear genome. Numts have been used to study differences in mutation rates between the nuclear and mitochondrial genomes, but have also been implicated as troublesome for phylogenetic studies and DNA-based species identification (i.e., DNA barcoding). In this study, a suspected numt discovered during a study of mitochondrial cytochrome c oxidase I (COI) diversity in North American birds was targeted and sequenced from tyrant flycatchers (family: Tyrannidae). In total, the numt was found in five taxa representing two genera. Substitution rates were compared between COI and numt sequences. None of the numt sequences harboured stop codons nor frameshift mutations, but phylogenetic analysis revealed they had accumulated more amino acid substitutions than the mitochondrial COI sequences. Mitochondrial COI appeared to be preferentially amplified in most cases, but methods for numt detection are discussed for cases like this where sequences lack obvious features for identification. Because of its persistence across a broad taxonomic lineage, this numt could form a valuable model system for studying evolution in numts. The full size of the numt and its location within the nuclear genome are yet to be determined.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Pseudogenes/genética , Aves Canoras/genética , Substituição de Aminoácidos , Animais , Sequência de Bases , DNA Mitocondrial/genética , Evolução Molecular , Variação Genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico
10.
BMC Infect Dis ; 10: 247, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20727178

RESUMO

BACKGROUND: Although many infections that are transmissible from person to person are acquired through direct contact between individuals, a minority, notably pulmonary tuberculosis (TB), measles and influenza are known to be spread by the airborne route. Airborne infections pose a particular threat to susceptible individuals whenever they are placed together with the index case in confined spaces. With this in mind, waiting areas of healthcare facilities present a particular challenge, since large numbers of people, some of whom may have underlying conditions which predispose them to infection, congregate in such spaces and can be exposed to an individual who may be shedding potentially pathogenic microorganisms. It is therefore important to understand the risks posed by infectious individuals in waiting areas, so that interventions can be developed to minimise the spread of airborne infections. METHOD: A stochastic Monte Carlo model was constructed to analyse the transmission of airborne infection in a hypothetical 132 m3 hospital waiting area in which occupancy levels, waiting times and ventilation rate can all be varied. In the model the Gammaitoni-Nucci equation was utilized to predict probability of susceptible individuals becoming infected. The model was used to assess the risk of transmission of three infectious diseases, TB, influenza and measles. In order to allow for stochasticity a random number generator was applied to the variables in the model and a total of 10000 individual simulations were undertaken. The mean quanta production rates used in the study were 12.7, 100 and 570 per hour for TB, influenza and measles, respectively. RESULTS: The results of the study revealed the mean probability of acquiring a TB infection during a 30-minute stay in the waiting area to be negligible (i.e. 0.0034), while that for influenza was an order of magnitude higher at 0.0262. By comparison the mean probability of acquiring a measles infection during the same period was 0.1349. If the duration of the stay was increased to 60 minutes then these values increased to 0.0087, 0.0662 and 0.3094, respectively. CONCLUSION: Under normal circumstances the risk of acquiring a TB infection during a visit to a hospital waiting area is minimal. Likewise the risks associated with the transmission of influenza, although an order of magnitude greater than those for TB, are relatively small. By comparison, the risks associated with measles are high. While the installation of air disinfection may be beneficial, when seeking to prevent the transmission of airborne viral infection it is important to first minimize waiting times and the number of susceptible individuals present before turning to expensive technological solutions.


Assuntos
Microbiologia do Ar , Doenças Transmissíveis/transmissão , Transmissão de Doença Infecciosa , Instalações de Saúde , Medição de Risco , Movimentos do Ar , Número Básico de Reprodução , Aglomeração , Humanos , Influenza Humana/transmissão , Sarampo/transmissão , Modelos Estatísticos , Fatores de Tempo , Tuberculose Pulmonar/transmissão
11.
BMC Infect Dis ; 10: 92, 2010 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-20384999

RESUMO

BACKGROUND: In recent years there has been renewed interest in the use of air ionizers to control the spread of infection in hospitals and a number of researchers have investigated the biocidal action of ions in both air and nitrogen. By comparison, the physical action of air ions on bacterial dissemination and deposition has largely been ignored. However, there is clinical evidence that air ions might play an important role in preventing the transmission of Acinetobacter infection. Although the reasons for this are unclear, it is hypothesized that a physical effect may be responsible: the production of air ions may negatively charge items of plastic medical equipment so that they repel, rather than attract, airborne bacteria. By negatively charging both particles in the air and items of plastic equipment, the ionizers minimize electrostatic deposition on these items. In so doing they may help to interrupt the transmission of Acinetobacter infection in certain healthcare settings such as intensive care units. METHODS: A study was undertaken in a mechanically ventilated room under ambient conditions to accurately measure changes in surface potential exhibited by items of plastic medical equipment in the presence of negative air ions. Plastic items were suspended on nylon threads, either in free space or in contact with a table surface, and exposed to negative ions produced by an air ionizer. The charge build-up on the specimens was measured using an electric field mill while the ion concentration in the room air was recorded using a portable ion counter. RESULTS: The results of the study demonstrated that common items of equipment such as ventilator tubes rapidly developed a large negative charge (i.e. generally >-100V) in the presence of a negative air ionizer. While most items of equipment tested behaved in a similar manner to this, one item, a box from a urological collection and monitoring system (the only item made from styrene acrylonitrile), did however develop a positive charge in the presence of the ionizer. CONCLUSION: The findings of the study suggest that the action of negative air ionizers significantly alters the electrostatic landscape of the clinical environment, and that this has the potential to cause any Acinetobacter-bearing particles in the air to be strongly repelled from some plastic surfaces and attracted to others. In so doing, this may prevent critical items of equipment from becoming contaminated with the bacterium.


Assuntos
Microbiologia do Ar , Ar/análise , Equipamentos e Provisões/microbiologia , Íons/análise , Plásticos , Acinetobacter/isolamento & purificação , Eletricidade , Humanos , Controle de Infecções/métodos
12.
Front Zool ; 6: 29, 2009 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-20003213

RESUMO

BACKGROUND: The Palearctic region supports relatively few avian species, yet recent molecular studies have revealed that cryptic lineages likely still persist unrecognized. A broad survey of cytochrome c oxidase I (COI) sequences, or DNA barcodes, can aid on this front by providing molecular diagnostics for species assignment. Barcodes have already been extensively surveyed in the Nearctic, which provides an interesting comparison to this region; faunal interchange between these regions has been very dynamic. We explored COI sequence divergence within and between species of Palearctic birds, including samples from Russia, Kazakhstan, and Mongolia. As of yet, there is no consensus on the best method to analyze barcode data. We used this opportunity to compare and contrast three different methods routinely employed in barcoding studies: clustering-based, distance-based, and character-based methods. RESULTS: We produced COI sequences from 1,674 specimens representing 398 Palearctic species. These were merged with published COI sequences from North American congeners, creating a final dataset of 2,523 sequences for 599 species. Ninety-six percent of the species analyzed could be accurately identified using one or a combination of the methods employed. Most species could be rapidly assigned using the cluster-based or distance-based approach alone. For a few select groups of species, the character-based method offered an additional level of resolution. Of the five groups of indistinguishable species, most were pairs, save for a larger group comprising the herring gull complex. Up to 44 species exhibited deep intraspecific divergences, many of which corresponded to previously described phylogeographic patterns and endemism hotspots. CONCLUSION: COI sequence divergence within eastern Palearctic birds is largely consistent with that observed in birds from other temperate regions. Sequence variation is primarily congruent with taxonomic boundaries; deviations from this trend reveal overlooked biological patterns, and in some cases, overlooked species. More research is needed to further refine the taxonomic status of some Palearctic birds, but large genetic surveys such as this may facilitate this effort. DNA barcodes are a practical means for rapid species assignment, although efficient analytical methods will likely require a two-tiered approach to differentiate closely related pairs of species.

14.
BMC Infect Dis ; 9: 64, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19445655

RESUMO

BACKGROUND: Good hand hygiene has for many years been considered to be the most important measure that can be applied to prevent the spread of healthcare-associated infection (HAI). Continuous emphasis on this intervention has lead to the widespread opinion that HAI rates can be greatly reduced by increased hand hygiene compliance alone. However, this assumes that the effectiveness of hand hygiene is not constrained by other factors and that improved compliance in excess of a given level, in itself, will result in a commensurate reduction in the incidence of HAI. However, there is evidence that the law of diminishing returns applies to hand hygiene, with the greatest benefits occurring in the first 20% or so of compliance. While this raises intriguing questions about the extent to which increasing compliance alone can further reduce rates of HAI, analysis of this subject has been hampered by a lack of quantifiable data relating to the risk of transmission between patients on wards. METHODS: In order to gain a greater understanding of the transmission of infection between patients via the hands of healthcare workers (HCWs), we constructed a stochastic Monte Carlo model to simulate the spread of methicillin-resistant Staphylococcus aureus (MRSA) between patients. We used the model to calculate the risk of transmission occurring, firstly between two patients in adjacent beds, and then between patients in a four-bedded bay. The aim of the study was to quantify the probability of transmission under a variety of conditions and thus to gain an understanding of the contribution made by the various factors which influence transmission. RESULTS: The study revealed that on a four-bedded bay, the average probability of transmitting an infection by the handborne route is generally low (i.e. in the region 0.002 - 0.013 depending on the hand hygiene behaviour of HCWs and other factors). However, because transmission is strongly influenced by stochastic events, it is the frequency with which 'high-risk events' occur, rather than average probability, that governs whether or not transmission will take place. The study revealed that increased hand hygiene compliance has a dramatic impact on the frequency with which 'high-risk events' occur. As compliance increases, so the rate at which 'high-risk events' occur, rapidly decreases, until a point is reached, beyond which, further hand hygiene is unlikely to yield any greater benefit. CONCLUSION: The findings of the study confirm those of other researchers and suggest that the greatest benefits derived from hand hygiene occur as a result of the first tranche of compliance, with higher levels (>50%) of hand hygiene events yielding only marginal benefits. This suggests that in most situations relatively little benefit is accrued from seeking to achieve very high levels of hand hygiene compliance.


Assuntos
Infecção Hospitalar/transmissão , Desinfecção das Mãos , Transmissão de Doença Infecciosa do Profissional para o Paciente , Staphylococcus aureus Resistente à Meticilina , Modelos Estatísticos , Método de Monte Carlo , Infecções Estafilocócicas/transmissão , Simulação por Computador , Fidelidade a Diretrizes , Pessoal de Saúde , Humanos , Infecções Estafilocócicas/microbiologia
15.
BMC Infect Dis ; 8: 114, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18764942

RESUMO

BACKGROUND: Hand hygiene is generally considered to be the most important measure that can be applied to prevent the spread of healthcare-associated infection (HAI). Continuous emphasis on this intervention has lead to the widespread opinion that HAI rates can be greatly reduced by increased hand hygiene compliance alone. However, this assumes that the effectiveness of hand hygiene is not constrained by other factors and that improved compliance in excess of a given level, in itself, will result in a commensurate reduction in the incidence of HAI. However, several researchers have found the law of diminishing returns to apply to hand hygiene, with the greatest benefits occurring in the first 20% or so of compliance, and others have demonstrated that poor cohorting of nursing staff profoundly influences the effectiveness of hand hygiene measures. Collectively, these findings raise intriguing questions about the extent to which increasing compliance alone can further reduce rates of HAI. METHODS: In order to investigate these issues further, we constructed a deterministic Ross-Macdonald model and applied it to a hypothetical general medical ward. In this model the transmission of staphylococcal infection was assumed to occur after contact with the transiently colonized hands of HCWs, who, in turn, acquire contamination only by touching colonized patients. The aim of the study was to evaluate the impact of imperfect hand cleansing on the transmission of staphylococcal infection and to identify, whether there is a limit, above which further hand hygiene compliance is unlikely to be of benefit. RESULTS: The model demonstrated that if transmission is solely via the hands of HCWs, it should, under most circumstances, be possible to prevent outbreaks of staphylococcal infection from occurring at a hand cleansing frequencies < 50%, even with imperfect hand hygiene. The analysis also indicated that the relationship between hand cleansing efficacy and frequency is not linear--as efficacy decreases, so the hand cleansing frequency required to ensure R0 < 1 increases disproportionately. CONCLUSION: Although our study confirmed hand hygiene to be an effective control measure, it demonstrated that the law of diminishing returns applies, with the greatest benefit derived from the first 20% or so of compliance. Indeed, our analysis suggests that there is little benefit to be accrued from very high levels of hand cleansing and that in most situations compliance > 40% should be enough to prevent outbreaks of staphylococcal infection occurring, if transmission is solely via the hands of HCWs. Furthermore we identified a non-linear relationship between hand cleansing efficacy and frequency, suggesting that it is important to maximise the efficacy of the hand cleansing process.


Assuntos
Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Desinfecção das Mãos , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/transmissão , Infecção Hospitalar/epidemiologia , Surtos de Doenças/prevenção & controle , Unidades Hospitalares , Humanos , Modelos Estatísticos , Infecções Estafilocócicas/epidemiologia
16.
BMC Infect Dis ; 8: 7, 2008 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-18218089

RESUMO

BACKGROUND: Clostridium difficile-associated diarrhoea (CDAD) is a frequently occurring healthcare-associated infection, which is responsible for significant morbidity and mortality amongst elderly patients in healthcare facilities. Environmental contamination is known to play an important contributory role in the spread of CDAD and it is suspected that contamination might be occurring as a result of aerial dissemination of C. difficile spores. However previous studies have failed to isolate C. difficile from air in hospitals. In an attempt to clarify this issue we undertook a short controlled pilot study in an elderly care ward with the aim of culturing C. difficile from the air. METHODS: In a survey undertaken during February (two days) 2006 and March (two days) 2007, air samples were collected using a portable cyclone sampler and surface samples collected using contact plates in a UK hospital. Sampling took place in a six bedded elderly care bay (Study) during February 2006 and in March 2007 both the study bay and a four bedded orthopaedic bay (Control). Particulate material from the air was collected in Ringer's solution, alcohol shocked and plated out in triplicate onto Brazier's CCEY agar without egg yolk, but supplemented with 5 mg/L of lysozyme. After incubation, the identity of isolates was confirmed by standard techniques. Ribotyping and REP-PCR fingerprinting were used to further characterise isolates. RESULTS: On both days in February 2006, C. difficile was cultured from the air with 23 samples yielding the bacterium (mean counts 53 - 426 cfu/m3 of air). One representative isolate from each of these was characterized further. Of the 23 isolates, 22 were ribotype 001 and were indistinguishable on REP-PCR typing. C. difficile was not cultured from the air or surfaces of either hospital bay during the two days in March 2007. CONCLUSION: This pilot study produced clear evidence of sporadic aerial dissemination of spores of a clone of C. difficile, a finding which may help to explain why CDAD is so persistent within hospitals and difficult to eradicate. Although preliminary, the findings reinforce concerns that current C. difficile control measures may be inadequate and suggest that improved ward ventilation may help to reduce the spread of CDAD in healthcare facilities.


Assuntos
Microbiologia do Ar , Poluentes Atmosféricos/análise , Clostridioides difficile/isolamento & purificação , Monitoramento Ambiental , Unidades Hospitalares , Idoso , Ar Condicionado , Estudos de Casos e Controles , Contagem de Colônia Microbiana , Infecção Hospitalar/microbiologia , Humanos , Instituições para Cuidados Intermediários , Ribotipagem , Vigilância de Evento Sentinela , Esporos/isolamento & purificação , Ventilação
17.
BMC Microbiol ; 7: 32, 2007 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-17439657

RESUMO

BACKGROUND: In recent years there has been renewed interest in the use of air ionisers to control of the spread of airborne infection. One characteristic of air ions which has been widely reported is their apparent biocidal action. However, whilst the body of evidence suggests a biocidal effect in the presence of air ions the physical and biological mechanisms involved remain unclear. In particular, it is not clear which of several possible mechanisms of electrical origin (i.e. the action of the ions, the production of ozone, or the action of the electric field) are responsible for cell death. A study was therefore undertaken to clarify this issue and to determine the physical mechanisms associated with microbial cell death. RESULTS: In the study seven bacterial species (Staphylococcus aureus, Mycobacterium parafortuitum, Pseudomonas aeruginosa, Acinetobacter baumanii, Burkholderia cenocepacia, Bacillus subtilis and Serratia marcescens) were exposed to both positive and negative ions in the presence of air. In order to distinguish between effects arising from: (i) the action of the air ions; (ii) the action of the electric field, and (iii) the action of ozone, two interventions were made. The first intervention involved placing a thin mica sheet between the ionisation source and the bacteria, directly over the agar plates. This intervention, while leaving the electric field unaltered, prevented the air ions from reaching the microbial samples. In addition, the mica plate prevented ozone produced from reaching the bacteria. The second intervention involved placing an earthed wire mesh directly above the agar plates. This prevented both the electric field and the air ions from impacting on the bacteria, while allowing any ozone present to reach the agar plate. With the exception of Mycobacterium parafortuitum, the principal cause of cell death amongst the bacteria studied was exposure to ozone, with electroporation playing a secondary role. However in the case of Mycobacterium parafortuitum, electroporation resulting from exposure to the electric field appears to have been the principal cause of cell inactivation. CONCLUSION: The results of the study suggest that the bactericidal action attributed to negative air ions by previous researchers may have been overestimated.


Assuntos
Ionização do Ar , Ânions/farmacologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cátions/farmacologia , Eletroquímica , Testes de Sensibilidade Microbiana , Nitrogênio/farmacologia , Eletricidade Estática
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3561-3563, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060667

RESUMO

Speech is an important aspect of human communication; individuals with speech impairment are unable to communicate vocally in real time. Our team has developed the TongueToSpeech (TTS) device with the goal of augmenting speech communication for the vocally impaired. The proposed device is a wearable wireless assistive device that incorporates a capacitive touch keyboard interface embedded inside a discrete retainer. This device connects to a computer, tablet or a smartphone via Bluetooth connection. The developed TTS application converts text typed by the tongue into audible speech. Our studies have concluded that an 8-contact point configuration between the tongue and the TTS device would yield the best user precision and speed performance. On average using the TTS device inside the oral cavity takes 2.5 times longer than the pointer finger using a T9 (Text on 9 keys) keyboard configuration to type the same phrase. In conclusion, we have developed a discrete noninvasive wearable device that allows the vocally impaired individuals to communicate in real time.


Assuntos
Tecnologia Assistiva , Humanos , Fala , Língua , Interface Usuário-Computador , Dispositivos Eletrônicos Vestíveis
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3852-3855, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060738

RESUMO

Controlling a computer or a smartphone's cursor allows the user to access a world full of information. For millions of people with limited upper extremities motor function, controlling the cursor becomes profoundly difficult. Our team has developed the User Interface Cursor-Controller (UIC-C) to assist the impaired individuals in regaining control over the cursor. The UIC-C is a hands-free device that utilizes the tongue muscle to control the cursor movements. The entire device is housed inside a subject specific retainer. The user maneuvers the cursor by manipulating a joystick imbedded inside the retainer via their tongue. The joystick movement commands are sent to an electronic device via a Bluetooth connection. The device is readily recognizable as a cursor controller by any Bluetooth enabled electronic device. The device testing results have shown that the time it takes the user to control the cursor accurately via the UIC-C is about three times longer than a standard computer mouse controlled via the hand. The device does not require any permanent modifications to the body; therefore, it could be used during the period of acute rehabilitation of the hands. With the development of modern smart homes, and enhancement electronics controlled by the computer, UIC-C could be integrated into a system that enables individuals with permanent impairment, the ability to control the cursor. In conclusion, the UIC-C device is designed with the goal of allowing the user to accurately control a cursor during the periods of either acute or permanent upper extremities impairment.


Assuntos
Dispositivos Eletrônicos Vestíveis , Mãos , Humanos , Tecnologia Assistiva , Língua , Interface Usuário-Computador
20.
G3 (Bethesda) ; 7(2): 755-773, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28087693

RESUMO

The Canadian beaver (Castor canadensis) is the largest indigenous rodent in North America. We report a draft annotated assembly of the beaver genome, the first for a large rodent and the first mammalian genome assembled directly from uncorrected and moderate coverage (< 30 ×) long reads generated by single-molecule sequencing. The genome size is 2.7 Gb estimated by k-mer analysis. We assembled the beaver genome using the new Canu assembler optimized for noisy reads. The resulting assembly was refined using Pilon supported by short reads (80 ×) and checked for accuracy by congruency against an independent short read assembly. We scaffolded the assembly using the exon-gene models derived from 9805 full-length open reading frames (FL-ORFs) constructed from the beaver leukocyte and muscle transcriptomes. The final assembly comprised 22,515 contigs with an N50 of 278,680 bp and an N50-scaffold of 317,558 bp. Maximum contig and scaffold lengths were 3.3 and 4.2 Mb, respectively, with a combined scaffold length representing 92% of the estimated genome size. The completeness and accuracy of the scaffold assembly was demonstrated by the precise exon placement for 91.1% of the 9805 assembled FL-ORFs and 83.1% of the BUSCO (Benchmarking Universal Single-Copy Orthologs) gene set used to assess the quality of genome assemblies. Well-represented were genes involved in dentition and enamel deposition, defining characteristics of rodents with which the beaver is well-endowed. The study provides insights for genome assembly and an important genomics resource for Castoridae and rodent evolutionary biology.


Assuntos
Genoma , Roedores/genética , Transcriptoma/genética , Animais , Genômica , Anotação de Sequência Molecular , Fases de Leitura Aberta/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA