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1.
PeerJ ; 10: e14371, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530405

RESUMO

It is now well evidenced that wildlife crossing structures paired with exclusion fencing reduce wildlife vehicles collisions while facilitating wildlife connectivity across roadways. Managing animal mortality and subpopulation connectivity is crucial to successful species and landscape stewardship. Highway mitigation projects are large economic investments that remain on the landscape for many decades. Governments and planning agents thus strive to balance cost and benefit to build cost-effective structures with the greatest positive impact on local wildlife and motorists. Ideal dimensions of overpasses and underpasses vary by species, but scientists generally suggest that overpasses for large mammals should be approximately 50 m wide. Optimal width also depends on structure length, with longer structures requiring additional width. Accordingly, experts have suggested a width to length ratio of 0.8. We sought to assess how these recommendations manifested in practice-where agencies use this information to design and build structures while also balancing cost and logistical challenges-and the degree to which built structures conform to current recommendations. We identified 120 wildlife overpasses across the world that were constructed to reduce the negative impacts of roads. Using a novel measurement technique, we analyzed the dimensions of these 120 overpasses located in North America, Europe, Asia, and Oceania. The average width of the wildlife overpasses was 34 m. Most wildlife overpasses located in North America and Europe did not meet their respective dimensional expert guidelines. We investigate reasons explaining the non-compliance and provide recommendations for future overpass designs. Building on previous evidence showing that wider overpasses have increased crossing rates, we examined crossing rates for multiple large mammal species across 12 overpasses located in western North America. We qualitatively observed that wider North American overpasses (40-60 m), in or near compliance with expert guidelines, were associated with a more diverse set of species use and had nearly twice the average crossing rates when compared to non-compliant, narrow North American overpasses. In reviewing various studies from around the world, we conclude that wide overpasses (~50 m) continue to present ecologically sound and cost-effective solutions for decreasing the barrier of roadways, especially when targeting width-sensitive species and large assemblages of mammals. Future studies, however, are encouraged to further explore the specific instances when underpasses and narrower overpasses present more cost-effective ecological solutions, or how these structures can complement wide overpasses in successful wildlife crossing systems.


Assuntos
Animais Selvagens , Mamíferos , Animais , América do Norte , Europa (Continente) , Ásia
2.
mSphere ; 4(5)2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484739

RESUMO

Urgency urinary incontinence (UUI) and overactive bladder (OAB) can both potentially be influenced by commensal and urinary tract infection-associated bacteria. The sensing of bladder filling involves interplay between various components of the nervous system, eventually resulting in contraction of the detrusor muscle during micturition. This study models host responses to various urogenital bacteria, first by using urothelial bladder cell lines and then with myofibroblast contraction assays. To measure responses, we examined Ca2+ influx, gene expression, and alpha smooth muscle actin deposition assays. Organisms such as Escherichia coli and Gardnerella vaginalis were found to strongly induce Ca2+ influx and contraction, whereas Lactobacillus crispatus and L. gasseri did not induce this response. Additionally, supernatants from lactobacilli impeded Ca2+ influx and contraction induced by uropathogens. Upon further investigation of factors associated with purinergic signaling pathways, the Ca2+ influx and contraction of cells correlated with the amount of extracellular ATP produced by E. coli Certain lactobacilli appear to mitigate this response by utilizing extracellular ATP or producing inhibitory compounds that may act as a receptor agonist or Ca2+ channel blocker. These findings suggest that members of the urinary microbiota may be influencing UUI or OAB.IMPORTANCE The ability of uropathogenic bacteria to release excitatory compounds, such as ATP, may act as a virulence factor to stimulate signaling pathways that could have profound effects on the urothelium, perhaps extending to the vagina. This may be countered by the ability of certain commensal urinary microbiota constituents, such as lactobacilli. Further understanding of these interactions is important for the treatment and prevention of UUI and OAB. The clinical implications may require a more targeted approach to enhance the commensal bacteria and reduce ATP release by pathogens.


Assuntos
Trifosfato de Adenosina/metabolismo , Bactérias/metabolismo , Cálcio/metabolismo , Miofibroblastos/citologia , Bexiga Urinária/microbiologia , Actinas/fisiologia , Bactérias/patogenicidade , Linhagem Celular , Colágeno/fisiologia , Humanos , Lactobacillales , Microbiota , Contração Muscular , Miofibroblastos/microbiologia , Simbiose , Bexiga Urinária/fisiologia , Urotélio/citologia
3.
J Endourol ; 33(7): 590-597, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31140304

RESUMO

Introduction and Objective: Urinary catheters and stents are frequently prone to catheter-associated urinary tract infections (CAUTI) through biofilm formation. Several strategies have been evaluated in search of a stent coating to reliably prevent adherence of bacteria and biofilm. Previous in vivo and in vitro research with methoxylated polyethylene glycol 3,4-dihydroxyphenylalanine (DOPA) copolymer as a candidate coating showed promising results to reduce the bacterial attachment. We aimed to further enhance this antimicrobial activity by adding antimicrobial agents to newly synthesized DOPA-based copolymers. Materials and Methods: Building on our previous experience, novel copolymers were engineered based on DOPA. Quaternary ammonium groups and silver particles were added by cross-linking to increase the antimicrobial activity through both kill-by-contact and planktonic killing. After coating polyurethane sheets and measuring contact angles, all candidate coatings were challenged in vitro with an Escherichia coli culture. The most promising coatings were then further evaluated against a panel of seven clinically relevant uropathogens and planktonic killing, and microbial attachment was determined. Results: Initially, seven coatings were developed, referred to as Surphys 093-099. The most significant increase in contact angle was identified in Surphys-095 and -098. Surphys coatings S-094, S-095, and S-098 were cross-linked with silver and exhibited profound antimicrobial properties when challenged with E. coli. Further testing demonstrated S-095 to have antimicrobial efficacy against gram-positive and gram-negative bacteria at different silver-loading concentrations. The final coating, consisting of a 2 mg/mL solution of S-095 cross-linked with 0.25 mg/mL AgNO3, appeared to be highly bactericidal showing a ≥99.9% bacterial killing effect while remaining below cytotoxicity levels. Conclusions: We were able to engineer DOPA-based copolymers and add quaternary ammonium and silver particles, thus increasing the bactericidal properties of the coating. These coatings have exhibited a biologically significant ability to prevent uropathogens from attaching to biomaterials and represent a realistic opportunity to combat CAUTI.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Di-Hidroxifenilalanina/farmacologia , Dopaminérgicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Poliuretanos , Infecções Urinárias/prevenção & controle , Anti-Infecciosos , Infecções Relacionadas a Cateter/prevenção & controle , Materiais Revestidos Biocompatíveis , Stents Farmacológicos , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Técnicas In Vitro , Klebsiella pneumoniae/efeitos dos fármacos , Teste de Materiais , Polímeros , Proteus mirabilis/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Nitrato de Prata/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus saprophyticus/efeitos dos fármacos , Cateteres Urinários
4.
Ecancermedicalscience ; 12: 867, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30263058

RESUMO

Precision medicine now needs to also consider the microbiome in oncology treatment. Ingested substances, whether they are a carcinogenic or therapeutic agent, will likely come into contact with the microbiota. Even those delivered extra-intestinally can be influenced beyond xenobiotic metabolism by biochemical factors associated with the microbiota or by an immunological predisposition created by the microbiome. We need to undertake one of the largest paradigm shifts to ever occur in medicine, that is, every drug or ingested substance needs to be re-evaluated for its pharmacological effect post-microbiome interaction. The importance of the microbiome with a focus on the treatment of cancer is discussed. In the near future, it may be possible to specifically manipulate the microbial composition within cancer patients to improve the therapeutic potential of existing oncological agents. However, the current tools to do so are limited. Targeted modulation is likely to be achieved by addition, selective enhancement or depletion of specific microbial types. This may include compounds such as narrow spectrum antimicrobial agents or oligosaccharides that will kill or enhance the bacterial growth of distinct members of the microbiota, respectively. This will stimulate a new era in these fields.

5.
Genet Med ; 19(2): 169-175, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27362910

RESUMO

PURPOSE: Cell-free DNA (cfDNA) testing for fetal aneuploidies was broadly implemented for common trisomies and sex-chromosome anomalies (SCAs). However, such an approach identifies only 75 to 85% of clinically relevant aneuploidies. METHODS: We present a consecutive series of 6,388 cases, thus uncovering a broader array of aneuploidies, including the rare autosomal trisomies (RATs) and the maternally inherited deletion and duplication copy-number variations (CNVs), with complete and stratified follow-up by amniocentesis. Combined measurements of z-scores and the fetal fraction, in conjunction with fetal cfDNA enrichment, were used to stratify the likelihood of true and false results. RESULTS: We obtained an incremental diagnostic yield of 50%; RATs and CNVs were found to be significant causes of fetal pathology. Scrutinizing z-scores and the fetal fraction made it possible to distinguish the sources of false-negative results; predict the likelihood of false-positive results for major trisomies and SCAs; classify maternal mosaic SCAs and CNVs, preventing false-positive results; and robustly identify maternally inherited CNVs and detect recurrent genomic disorders as a standardized function of the fetal fraction. CONCLUSION: With the clinical pertinence of this broader detection scheme confirmed, we offer recommendations for its implementation.Genet Med 19 2, 169-175.


Assuntos
Ácidos Nucleicos Livres/genética , Aberrações Cromossômicas , Transtornos Cromossômicos/genética , Trissomia/genética , Aneuploidia , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/patologia , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Cariotipagem , Gravidez , Aberrações dos Cromossomos Sexuais , Trissomia/fisiopatologia
6.
BMJ Case Rep ; 20152015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26531740

RESUMO

An asymptomatic 48-year-old man presented with a right-sided neck mass. A CT scan demonstrated a lesion at the carotid bifurcation and an angiogram showed splaying of the carotid arteries. His plasma metanephrines were raised confirming a catecholamine-secreting paraganglioma. Metaiodobenzylguanidine single-photon emission CT showed focal high tracer uptake in the right of the neck. Histology revealed a tumour, arising within a nerve, composed of oval-shaped cells arranged in nested (zellballen) as well as in trabecular patterns. Immunohistochemistry was positive for neuroendocrine markers chromogranin A, synaptophysin and CD56. Preoperative management included an endocrinologist initiating α-adrenergic and ß-adrenergic blockers. Intraoperatively, acute hypertension occurred whenever the tumour was manipulated. Close communication between the surgeons and the anaesthetist allowed for these episodes to be predicted and treated with fast-acting antihypertensives such as sodium nitroprusside. Postoperatively, the patient recovered well and his antihypertensives were discontinued.


Assuntos
Anti-Hipertensivos/uso terapêutico , Catecolaminas/sangue , Neoplasias de Cabeça e Pescoço/metabolismo , Hipertensão/tratamento farmacológico , Paraganglioma/metabolismo , Neoplasias do Sistema Nervoso Periférico/metabolismo , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Paraganglioma/complicações , Paraganglioma/cirurgia , Assistência Perioperatória , Neoplasias do Sistema Nervoso Periférico/complicações , Neoplasias do Sistema Nervoso Periférico/cirurgia
7.
Appl Microbiol Biotechnol ; 98(7): 3157-64, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24162085

RESUMO

Bio-fixation of carbon dioxide (CO2) by microalgae has been recognised as an attractive approach to offset anthropogenic emissions. Biological carbon mitigation is the process whereby autotrophic organisms, such as microalgae, convert CO2 into organic carbon and O2 through photosynthesis; this process through respiration produces biomass. In this study Dunaliella tertiolecta was cultivated in a semicontinuous culture to investigate the carbon mitigation rate of the system. The algae were produced in 1.2-L Roux bottles with a working volume of 1 L while semicontinuous production commenced on day 4 of cultivation when the carbon mitigation rate was found to be at a maximum for D. tertiolecta. The reduction in CO2 between input and output gases was monitored to predict carbon fixation rates while biomass production and microalgal carbon content are used to calculate the actual carbon mitigation potential of D. tertiolecta. A renewal rate of 45 % of flask volume was utilised to maintain the culture in exponential growth with an average daily productivity of 0.07 g L(-1) day(-1). The results showed that 0.74 g L(-1) of biomass could be achieved after 7 days of semicontinuous production while a total carbon mitigation of 0.37 g L(-1) was achieved. This represented an increase of 0.18 g L(-1) in carbon mitigation rate compared to batch production of D. tertiolecta over the same cultivation period.


Assuntos
Dióxido de Carbono/metabolismo , Fotobiorreatores/microbiologia , Volvocida/crescimento & desenvolvimento , Volvocida/metabolismo , Biomassa , Ciclo do Carbono
8.
J Microbiol Methods ; 90(2): 137-43, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22521923

RESUMO

This paper describes a microalgal cell lipid fluorescence enhancement method using BODIPY(505/515), which can be used to screen for lipids in wild-type microalgae and to monitor lipid content within microalgae production processes to determine optimal harvesting time. The study was based on four microalgae species (Dunaliella teteriolecta, Tetraselmis suecica, Nannochloropsis oculata, and Nannochloris atomus) selected because of their inherent high lipid content. An extended analysis was carried out with N. oculata due to the depressed fluorescence observed when compared with the other experimental strains. BODIPY(505/515) lipid fluorescence was determined for two solvent pre-treatment methods (DMSO and glycerol) and four staining condition parameters (analysis time, staining temperature, dye concentration, and algal cell concentration). It was found that lipid fluorescence of thick cell-walled microalgae, such as N. oculata, is significantly enhanced by both the pre-treatment methods and staining condition parameters, thereby significantly enhancing lipid fluorescence by ca. 800 times the base autofluorescence. The lipid fluorescence enhancement method provides a quick and simple index for in vivo Flow Cytometry quantification of total lipid contents for purposes of species screening or whole culture monitoring in biofuel-directed microalgae production.


Assuntos
Biocombustíveis/microbiologia , Compostos de Boro/metabolismo , Corantes Fluorescentes/metabolismo , Lipídeos/análise , Microalgas/química , Microalgas/crescimento & desenvolvimento , Coloração e Rotulagem/métodos , Reatores Biológicos/microbiologia , Biotecnologia/métodos , Fluorescência , Microalgas/metabolismo
9.
Paediatr Anaesth ; 21(6): 630-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21414078

RESUMO

Increasing numbers of children with congenital and chronic diseases are surviving beyond adolescence. Consequently, arrangements must be put in place to ensure that these groups of patients continue to receive high-quality care into adulthood. Although some medical disciplines have reacted positively to this growing challenge, perioperative care has lagged behind. This review explores some of the difficulties in delivering optimal perioperative care in the transitional period. Key issues, including the paucity of experience in the management of pediatric diseases among adult-trained clinicians and unfamiliarity with child/family focused care, are discussed. We provide some suggestions for the development of transitional healthcare policies.


Assuntos
Continuidade da Assistência ao Paciente/estatística & dados numéricos , Serviços de Saúde/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Assistência Perioperatória/estatística & dados numéricos , Adolescente , Adulto , Analgesia Controlada pelo Paciente , Analgésicos Opioides/efeitos adversos , Anestesiologia/educação , Paralisia Cerebral/complicações , Criança , Doença Crônica , Overdose de Drogas , Evolução Fatal , Feminino , Humanos , Síndrome de Klippel-Feil/complicações , Masculino , Paraparesia Espástica/terapia , Aspiração Respiratória , Cirurgia Plástica , Parede Torácica/anormalidades , Parede Torácica/cirurgia
10.
Paediatr Anaesth ; 18(10): 957-66, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18673319

RESUMO

BACKGROUND: There is a lack of information about the prevalence, manifestations, and management of chronic pain in children in the UK. We surveyed consultants with an interest in chronic pain management and general practitioners (GPs) in the UK in order to understand their perspective on chronic pain in children. METHODS: We conducted a postal survey of clinicians with an interest in chronic pain management and GPs in the UK. The survey contained questions relating to the following aspects of managing children with chronic pain: (i) clinicians' training and experience; (ii) available resources; (iii) perceived prevalence, presentation, and referral patterns; (iv) interventions; and (v) outcomes. RESULTS: 472 pain clinicians and 131 GPs were contacted. The response rates were 55% and 61% respectively. Of the respondents, 77% of pain clinicians and 95% of GPs acknowledged a lack of adequate training for managing children with chronic pain. 57% of the pain clinicians and 63% of the GPs reported that the prevalence of chronic pain in children was <5%. In the comments section, 22% of those respondents who frequently manage children with chronic pain reported an increase in the incidence of this problem over the last 5 years. The common chronic pain syndromes in children were reported to be: musculoskeletal and limb pain, recurrent abdominal and pelvic pain, and headache. 15% of the respondents advised that children with chronic pain would be best managed in specialist pediatric centers and 75% opined that majority of children with chronic pain have a fair to good prognosis. CONCLUSIONS: More information is required about prevalence, manifestations and long-term effects of chronic pain in children in the UK. There is a need for increasing training and resources amongst GPs and pain clinicians for managing chronic pain in the pediatric age group.


Assuntos
Analgesia , Medicina de Família e Comunidade , Dor , Inquéritos e Questionários , Anestesiologia/educação , Criança , Doença Crônica , Medicina de Família e Comunidade/educação , Pesquisas sobre Atenção à Saúde , Humanos , Dor/epidemiologia , Dor/etiologia , Manejo da Dor , Prevalência , Prognóstico , Encaminhamento e Consulta/estatística & dados numéricos , Reino Unido/epidemiologia
12.
Intensive Care Med ; 34(8): 1469-76, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18350270

RESUMO

OBJECTIVES: To measure the extent of dilution of helium-oxygen (heliox) by room air when given via high concentration reservoir mask to spontaneously breathing subjects. Substantial dilution of heliox by room air under these circumstances might alter its physical properties sufficiently to negate any potential clinical benefit in obstructive respiratory failure. DESIGN: Healthy volunteers breathing different concentrations of helium in oxygen via two different masks in a randomised crossover design. SETTING: Operating theatre in a university hospital. PATIENTS AND PARTICIPANTS: Six healthy volunteers. INTERVENTIONS: The concentrations of helium, nitrogen and oxygen were measured in the trachea of each volunteer using a mass spectrometer during normal breathing, hyperventilation and hypoventilation. MEASUREMENTS AND RESULTS: During normal breathing of Heliox21 (79% helium) via a standard non-rebreathe reservoir mask, within subject median percentage tracheal helium was 37.2% (range 29.3-52.2%) and nitrogen was 41.7% (27.4-49.4%). Air entrainment was affected by changes in breathing pattern: tracheal nitrogen concentration was greater during hyperventilation (55.4%; range 49.4-63.5%) and less during hypoventilation (33.1%; range 24.6-39.6%, p=0.043). Tracheal nitrogen could be almost completely abolished by administering heliox via a tightly fitting cushioned facemask, even during hyperventilation (2.2%; range 0.6-6.1%, p=0.028). CONCLUSIONS: Heliox administration via a standard high-concentration reservoir mask leads to significant dilution by room air. For the full potential benefits of heliox to be realised in spontaneously breathing patients, it should be administered via a system that achieves a gas tight seal, with no leaks between the delivery device and the surroundings.


Assuntos
Sistemas de Liberação de Medicamentos/instrumentação , Hélio/administração & dosagem , Hélio/farmacologia , Máscaras , Oxigênio/administração & dosagem , Oxigênio/farmacologia , Traqueia/efeitos dos fármacos , Adulto , Estudos Cross-Over , Relação Dose-Resposta a Droga , Desenho de Equipamento , Feminino , Humanos , Masculino , Respiração/efeitos dos fármacos , Volume de Ventilação Pulmonar/efeitos dos fármacos
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