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1.
J Environ Manage ; 290: 112589, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33906116

RESUMO

Agri-environment schemes (AES) are key mechanisms to deliver conservation policy, and include management to provide resources for target taxa. Mobile species may move to areas where resources are increased, without this necessarily having an effect across the wider countryside or on populations over time. Most assessments of AES efficacy have been at small spatial scales, over short timescales, and shown varying results. We developed a survey design based on orthogonal gradients of AES management at local and landscape scales, which will enable the response of several taxa to be monitored. An evidence review of management effects on butterflies, birds and pollinating insects provided data to score AES options. Predicted gradients were calculated using AES uptake, weighted by the evidence scores. Predicted AES gradients for each taxon correlated strongly, and with the average gradient across taxa, supporting the co-location of surveys across different taxa. Nine 1 × 1 km survey squares were selected in each of four regional blocks with broadly homogenous background habitat characteristics. Squares in each block covered orthogonal contrasts across the range of AES gradients at local and landscape scales. This allows the effects of AES on species at each scale, and the interaction between scales, to be tested. AES options and broad habitats were mapped in field surveys, to verify predicted gradients which were based on AES option uptake data. The verified AES gradient had a strong positive relationship with the predicted gradient. AES gradients were broadly independent of background habitat within each block, likely allowing AES effects to be distinguished from potential effects of other habitat variables. Surveys of several mobile taxa are ongoing. This design will allow mobile taxa responses to AES to be tested in the surrounding countryside, as well as on land under AES management, and potentially in terms of population change over time. The design developed here provides a novel, pseudo-experimental approach for assessing the response of mobile species to gradients of management at two spatial scales. A similar design process could be applied in other regions that require a standardized approach to monitoring the impacts of management interventions on target taxa at landscape scales, if equivalent spatial data are available.


Assuntos
Agricultura , Borboletas , Animais , Biodiversidade , Aves , Ecossistema , Meio Ambiente
2.
J Dairy Sci ; 100(10): 8438-8442, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28755946

RESUMO

Previous data have demonstrated that refractometers can be used to estimate serum IgG, and that a cut-point of 7.8% Brix should be used to identify failure of passive transfer (FPT) in 1-d-old Holstein calves. The objective of the present study was to validate the use of refractometry to estimate serum IgG concentrations and evaluate FPT in Jersey calves. Blood samples (n = 97) were obtained from 1- to 3-d-old Jersey calves and centrifuged at 3,300 × g for 20 min at 25°C. Serum was analyzed for % Brix, total protein (TP), and refractive index (nD) using a Sper Scientific Digital Refractometer (model #300036, Sper Scientific, Scottsdale, AZ) within 12 h of sampling. Samples were then frozen and later analyzed in the laboratory for IgG by radial immunodiffusion. The mean serum IgG concentration for all calves was 23.7 mg/mL (SD = 12.5), with a range of 2.3 to 65.5 mg/mL. Mean serum % Brix was 8.9 (SD = 1.1; range 6.5 to 12.0). Serum % Brix was moderately correlated with IgG concentration (r = 0.77). Total protein and IgG were moderately correlated (r = 0.790). Regression was used to determine cut-points for approximately 10, 12, and 14 mg of IgG/mL and to determine the sensitivity and specificity of refractometry to identify FPT (serum IgG <10 mg/mL at 24 h of life). Brix cut-points analyzed were 7.1, 7.3, and 7.6%; TP cut-points were 4.6, 5.0, and 5.5 g/dL; and nD cut-points were 1.34332, 1.34271, and 1.3448, respectively, for 10, 12, and 14 mg of IgG/mL. The 7.3% Brix and 4.6 g/dL TP cut-points resulted in the greatest percentage of samples being correctly classified. These data suggest that digital refractometry is an acceptable and rapid method to estimate immunoglobulin G in Jersey calf serum.


Assuntos
Imunidade Coletiva , Imunização Passiva/veterinária , Imunoglobulina G/sangue , Refratometria/veterinária , Animais , Animais Recém-Nascidos , Bovinos , Colostro , Congelamento , Imunização Passiva/métodos , Imunodifusão/métodos , Imunodifusão/veterinária , Refratometria/instrumentação , Sensibilidade e Especificidade
3.
Antimicrob Agents Chemother ; 59(7): 4315-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25896693

RESUMO

Of 1,927 Enterococcus species isolates collected across Canada from 2007 to 2013, 80 (4.2%) were identified as vancomycin-resistant enterococci (VRE). VRE infections during this time tripled in Canadian hospitals, from 1.8% to 6.0% (P = 0.03). All VRE were Enterococcus faecium, with 90% possessing vanA. The prevalence of vanB decreased from 37.5% in 2007 to 0% in 2013 (P < 0.05). The VRE were multidrug resistant, but 70.6%, 86.3%, and 100% were susceptible to doxycycline, linezolid, and daptomycin, respectively.


Assuntos
Enterococcus/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Resistência a Vancomicina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Canadá/epidemiologia , Carbono-Oxigênio Ligases/genética , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla/genética , Enterococcus faecium/efeitos dos fármacos , Feminino , Hospitais , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Vigilância em Saúde Pública , Vancomicina/farmacologia , Adulto Jovem
4.
J Virol ; 88(4): 1881-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24198426

RESUMO

Dengue virus (DENV), the etiologic agent of dengue fever, is transmitted during probing of human skin by infected-mosquito bite. The expectorated viral inoculum also contains an assortment of mosquito salivary proteins that have been shown to modulate host hemostasis and innate immune responses. To examine the potential role of mosquito probing in DENV establishment within the vertebrate host, we inoculated mice intradermally with DENV serotype 2 strain 1232 at sites where Aedes aegypti had or had not probed immediately prior. We assayed these sites 3 h postinoculation with transcript arrays for the Toll-like receptor (TLR), RIG-I-like receptor, and NOD-like receptor signaling pathways of the innate immune system. We then chose TLR7, transcription factor p65 (RelA), gamma interferon (IFN-γ), and IFN-γ-inducible protein 10 (IP-10) from the arrays for further investigation and assayed these transcripts at 10 min, 3 h, and 6 h postinoculation. The transcripts for TLR7, RelA, IFN-γ, and IP-10 were significantly downregulated between 2- and 3-fold in the group subjected to mosquito probing relative to the virus-only inoculation group at 3 h postinoculation. A reduction in these transcripts could indicate reduced DENV recognition and antigen presentation and diminished inhibition of viral replication and spread. Further, mosquito probing resulted in viremia titers significantly higher than those in mice that did not receive probing. A. aegypti probing has a significant effect on the innate immune response to DENV infection and generates an early immune environment more permissive to the establishment of infection.


Assuntos
Aedes/virologia , Vírus da Dengue , Dengue/transmissão , Imunidade Inata/imunologia , Mordeduras e Picadas de Insetos/imunologia , Insetos Vetores/virologia , Transdução de Sinais/imunologia , Aedes/imunologia , Análise de Variância , Animais , Quimiocina CXCL10/imunologia , Primers do DNA/genética , Dengue/imunologia , Regulação da Expressão Gênica/imunologia , Insetos Vetores/imunologia , Interferon gama/imunologia , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Receptores Toll-Like/imunologia , Fator de Transcrição RelA/imunologia
5.
J Antimicrob Chemother ; 68(7): 1505-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23524466

RESUMO

OBJECTIVES: Vancomycin-resistant enterococci (VRE) can be associated with serious bacteraemia. The focus of this study was to characterize the molecular epidemiology of VRE from bacteraemia cases that were isolated from 1999 to 2009 as part of Canadian Nosocomial Infection Surveillance Program (CNISP) surveillance activities. METHODS: From 1999 to 2009, enterococci were collected from across Canada in accordance with the CNISP VRE surveillance protocol. MICs were determined using broth microdilution. PCR was used to identify vanA, B, C, D, E, G and L genes. Genetic relatedness was examined using multilocus sequence typing (MLST). RESULTS: A total of 128 cases of bacteraemia were reported to CNISP from 1999 to 2009. In 2007, a significant increase in bacteraemia rates was observed in western and central Canada. Eighty-one of the 128 bacteraemia isolates were received for further characterization and were identified as Enterococcus faecium. The majority of isolates were from western Canada (60.5%), followed by central (37.0%) and eastern (2.5%) Canada. Susceptibilities were as follows: daptomycin, linezolid, tigecycline and chloramphenicol, 100%; quinupristin/dalfopristin, 96.3%; high-level gentamicin, 71.6%; tetracycline, 50.6%; high-level streptomycin, 44.4%; rifampicin, 21.0%; nitrofurantoin, 11.1%; clindamycin, 8.6%; ciprofloxacin, levofloxacin and moxifloxacin, 1.2%; and ampicillin, 0.0%. vanA contributed to vancomycin resistance in 90.1% of isolates and vanB in 9.9%. A total of 17 sequence types (STs) were observed. Beginning in 2006 there was a shift in ST from ST16, ST17, ST154 and ST80 to ST18, ST412, ST203 and ST584. CONCLUSIONS: The increase in bacteraemia observed since 2007 in western and central Canada appears to coincide with the shift of MLST STs. All VRE isolates remained susceptible to daptomycin, linezolid, chloramphenicol and tigecycline.


Assuntos
Bacteriemia/epidemiologia , Infecção Hospitalar/epidemiologia , Enterococcus faecium/classificação , Infecções por Bactérias Gram-Positivas/epidemiologia , Resistência a Vancomicina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/microbiologia , Canadá/epidemiologia , Criança , Pré-Escolar , Infecção Hospitalar/microbiologia , DNA Bacteriano/genética , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Feminino , Genes Bacterianos , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Adulto Jovem
6.
J Pharmacol Exp Ther ; 336(1): 145-54, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20876231

RESUMO

GABA type A receptors (GABA(A)-Rs) are potential targets of ethanol. However, there are multiple subtypes of this receptor, and, thus far, individual subunits have not been definitively linked with specific ethanol behavioral actions. Interestingly, though, a chromosomal cluster of four GABA(A)-R subunit genes, including α2 (Gabra2), was associated with human alcoholism (Am J Hum Genet 74:705-714, 2004; Pharmacol Biochem Behav 90:95-104, 2008; J Psychiatr Res 42:184-191, 2008). The goal of our study was to determine the role of receptors containing this subunit in alcohol action. We designed an α2 subunit with serine 270 to histidine and leucine 277 to alanine mutations that was insensitive to potentiation by ethanol yet retained normal GABA sensitivity in a recombinant expression system. Knockin mice containing this mutant subunit were tested in a range of ethanol behavioral tests. These mutant mice did not develop the typical conditioned taste aversion in response to ethanol and showed complete loss of the motor stimulant effects of ethanol. Conversely, they also demonstrated changes in ethanol intake and preference in multiple tests. The knockin mice showed increased ethanol-induced hypnosis but no difference in anxiolytic effects or recovery from acute ethanol-induced motor incoordination. Overall, these studies demonstrate that the effects of ethanol at GABAergic synapses containing the α2 subunit are important for specific behavioral effects of ethanol that may be relevant to the genetic linkage of this subunit with human alcoholism.


Assuntos
Aprendizagem da Esquiva/fisiologia , Condicionamento Psicológico/fisiologia , Etanol/administração & dosagem , Atividade Motora/genética , Receptores de GABA-A/genética , Paladar/genética , Consumo de Bebidas Alcoólicas/genética , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Feminino , Técnicas de Introdução de Genes , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Paladar/efeitos dos fármacos , Xenopus laevis
7.
J Pharmacol Exp Ther ; 336(1): 134-44, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20807777

RESUMO

The mechanism by which the inhaled anesthetic isoflurane produces amnesia and immobility is not understood. Isoflurane modulates GABA(A) receptors (GABA(A)-Rs) in a manner that makes them plausible targets. We asked whether GABA(A)-R α2 subunits contribute to a site of anesthetic action in vivo. Previous studies demonstrated that Ser270 in the second transmembrane domain is involved in the modulation of GABA(A)-Rs by volatile anesthetics and alcohol, either as a binding site or a critical allosteric residue. We engineered GABA(A)-Rs with two mutations in the α2 subunit, changing Ser270 to His and Leu277 to Ala. Recombinant receptors with these mutations demonstrated normal affinity for GABA, but substantially reduced responses to isoflurane. We then produced mutant (knockin) mice in which this mutated subunit replaced the wild-type α2 subunit. The adult mutant mice were overtly normal, although there was evidence of enhanced neonatal mortality and fear conditioning. Electrophysiological recordings from dentate granule neurons in brain slices confirmed the decreased actions of isoflurane on mutant receptors contributing to inhibitory synaptic currents. The loss of righting reflex EC(50) for isoflurane did not differ between genotypes, but time to regain the righting reflex was increased in N(2) generation knockins. This effect was not observed at the N(4) generation. Isoflurane produced immobility (as measured by tail clamp) and amnesia (as measured by fear conditioning) in both wild-type and mutant mice, and potencies (EC(50)) did not differ between the strains for these actions of isoflurane. Thus, immobility or amnesia does not require isoflurane potentiation of the α2 subunit.


Assuntos
Anestésicos Inalatórios/administração & dosagem , Resistência a Medicamentos/fisiologia , Isoflurano/administração & dosagem , Receptores de GABA-A/fisiologia , Animais , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Resistência a Medicamentos/efeitos dos fármacos , Medo/efeitos dos fármacos , Medo/fisiologia , Feminino , Técnicas de Introdução de Genes , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Receptores de GABA-A/genética , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/genética , Xenopus laevis , Ácido gama-Aminobutírico/farmacologia
8.
J Antimicrob Chemother ; 64(3): 552-5, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19578083

RESUMO

OBJECTIVES: Multidrug-resistant (MDR) Acinetobacter baumannii is a growing concern in many countries. This report describes patient demographics, antimicrobial susceptibilities and molecular characteristics of A. baumannii cases identified through the Canadian Ward Surveillance Study (CANWARD). In addition, clinical cases involving MDR carbapenem-resistant A. baumannii are also detailed in this report. METHODS: From January to December 2007, 12 hospital centres across Canada submitted pathogens from clinics, emergency rooms, intensive care units and medical/surgical wards as part of the CANWARD study. MICs were determined using microbroth dilution (CLSI). PCR and sequence analysis identified OXA genes among carbapenem-resistant isolates. PFGE was used to determine genetic relatedness and compare representatives of the Midlands 2 strain, OXA-23 clone 1 or 2, T strains and isolates collected from military sources. RESULTS: This study identified A. baumannii in 0.33% (n = 26) of infections. The majority of isolates remained susceptible to the antimicrobials tested, however, 7.7% (n = 2) displayed an MDR phenotype, including resistance to carbapenems. In one isolate bla(OXA-58) was found to be the likely cause of carbapenem resistance while the other isolate had an insertion sequence element upstream of its intrinsic bla(OXA-51). The clinical data of these two isolates suggest that one is travel-related while the source of the other remains unknown. CONCLUSIONS: A. baumannii infections from Canadian hospitals were relatively low. Carbapenem-resistant MDR A. baumannii were also rare and unrelated to previously observed isolates from military sources. Continued surveillance in Canada is suggested in order to determine if such organisms will become a problem.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Canadá , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Hospitais , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Adulto Jovem , beta-Lactamases/genética
9.
Vet Microbiol ; 134(3-4): 279-87, 2009 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-18824313

RESUMO

The aim of this study was to determine the molecular epidemiology of cefoxitin-resistance Escherichia coli identified in cattle entering feedlots and determine if there were any similarities to E. coli causing human infections in Canadian hospitals. A total of 51 E. coli were isolated from a total of 2483 cattle entering four feedlots in southern Alberta, Canada. DNA fingerprinting using pulsed-field gel electrophoresis revealed thirty-two unique patterns with two major clusters observed comprised of Cluster A (11 strains) and Cluster B (7 strains). PCR and sequence analysis revealed 38 isolates (74.5%) harboured bla(CMY-2), whereas the remainder were found to contain mutations in the promoter region of the chromosomal ampC gene, which has been previously associated with cefoxitin resistance. No resistance to nalidixic acid, ciprofloxacin, or amikacin was observed in the clinical isolates. bla(CMY-2) harbouring plasmids were transferred to E. coli DH10B. All of the plasmids carrying bla(CMY-2) contained the A/C replicon and also harboured other resistance genes. Plasmid fingerprinting using BglII revealed 17 unique patterns with all but one clustering within 70% similarity. Comparison of the plasmid fingerprints to those isolated from human clinically significant E. coli in Canada during a similar time period [Mulvey, M.R., Bryce, E., Boyd, D.A., Ofner-Agostini, M., Land, A.M., Simor, A.E, Paton, S., 2005. The Canadian Hospital Epidemiology Committee, and The Canadian Nosocomial Infection Surveillance Program, Health Canada. Molecular characterization of cefoxitin resistant Escherichia coli from Canadian hospitals. Antimicrob. Agents Chemother. 49, 358-365] revealed four strains that harboured bla(CMY-2) A/C replicon type plasmid with fingerprint similarities of greater than 90% to the ones identified in E. coli from the cattle in this study. These findings highlight the potential linkage of multidrug resistant organisms in food producing animals and human infections in Canadian hospitals. The plasmids conferred resistance to multiple antibiotics which could limit options for the treatment of infections caused by these strains.


Assuntos
Cefoxitina/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Escherichia coli/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Plasmídeos/genética , Animais , Antibacterianos/farmacologia , Canadá/epidemiologia , Bovinos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecções por Escherichia coli/epidemiologia , Humanos , Epidemiologia Molecular , Filogenia
10.
Nat Commun ; 10(1): 1481, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30931943

RESUMO

How insects promote crop pollination remains poorly understood in terms of the contribution of functional trait differences between species. We used meta-analyses to test for correlations between community abundance, species richness and functional trait metrics with oilseed rape yield, a globally important crop. While overall abundance is consistently important in predicting yield, functional divergence between species traits also showed a positive correlation. This result supports the complementarity hypothesis that pollination function is maintained by non-overlapping trait distributions. In artificially constructed communities (mesocosms), species richness is positively correlated with yield, although this effect is not seen under field conditions. As traits of the dominant species do not predict yield above that attributed to the effect of abundance alone, we find no evidence in support of the mass ratio hypothesis. Management practices increasing not just pollinator abundance, but also functional divergence, could benefit oilseed rape agriculture.


Assuntos
Biodiversidade , Brassica rapa , Produção Agrícola , Produtos Agrícolas , Insetos , Polinização , Animais
12.
Adv Immunol ; 131: 187-231, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27235684

RESUMO

Positron emission tomography (PET) is a powerful noninvasive imaging technique able to measure distinct biological processes in vivo by administration of a radiolabeled probe. Whole-body measurements track the probe accumulation providing a means to measure biological changes such as metabolism, cell location, or tumor burden. PET can also be applied to both preclinical and clinical studies providing three-dimensional information. For immunotherapies (in particular understanding T cell responses), PET can be utilized for spatial and longitudinal tracking of T lymphocytes. Although PET has been utilized clinically for over 30 years, the recent development of additional PET radiotracers have dramatically expanded the use of PET to detect endogenous or adoptively transferred T cells in vivo. Novel probes have identified changes in T cell quantity, location, and function. This has enabled investigators to track T cells outside of the circulation and in hematopoietic organs such as spleen, lymph nodes, and bone marrow, or within tumors. In this review, we cover advances in PET detection of the antitumor T cell response and areas of focus for future studies.


Assuntos
Imunoterapia Adotiva/métodos , Neoplasias/terapia , Tomografia por Emissão de Pósitrons/métodos , Linfócitos T/imunologia , Animais , Antígenos de Neoplasias/imunologia , Movimento Celular , Humanos , Imageamento Tridimensional , Ativação Linfocitária , Imagem Molecular , Neoplasias/imunologia , Tomografia por Emissão de Pósitrons/tendências , Linfócitos T/transplante
13.
Biomaterials ; 26(34): 7046-56, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15964067

RESUMO

Mimicking endogenous bone-binding proteins, RGD peptides have been synthesized with polyacidic amino acid domains in order to ionically tether the peptides to bone-like synthetic biomaterials, including hydroxyapatite (HA). However, a direct comparison of unmodified RGD with polyacidic-conjugated RGD has not been performed, and thus a benefit for the acidic domain has not been established. We evaluated the peptide/HA bond of RGD peptides with and without an attached polyglutamate sequence (E(7)), as well as examined mesenchymal stem cell (MSC) adhesion and morphology as they were affected by the conjugated peptide. We found that significantly more E(7)RGD was bound to HA than RGD at all coating concentrations tested, and moreover, more E(7)RGD was retained on the HA surface even after extended washing in serum-free media. Consistent with in vitro results, higher levels of E(7)RGD than RGD remained on HA that had been implanted in vivo for 24 h, indicating that the polyacidic domain improved peptide-binding efficiency. At several peptide concentrations, E(7)RGD increased cell adhesion compared to RGD surfaces, establishing a biological benefit for the E(7) modification. In addition, HA pre-coated sequentially with low-density E(7)RGD (1-10 microg/ml) and serum (FBS) stimulated cell adhesion and spreading, compared to either coating alone, suggesting that an ionic linkage allows for the potential adsorption of serum proteins to unoccupied sites, which may be important for bone formation in vivo. Collectively, these results suggest that tethering peptides to HA via a polyglutamate domain is an effective method for improving the peptide/HA bond, as well as for enhancing MSC adhesion.


Assuntos
Substitutos Ósseos/farmacologia , Adesão Celular/efeitos dos fármacos , Durapatita/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Oligopeptídeos/farmacologia , Osteogênese/efeitos dos fármacos , Ácido Poliglutâmico/farmacologia , Adolescente , Adsorção , Adulto , Substitutos Ósseos/química , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Relação Dose-Resposta a Droga , Durapatita/farmacologia , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Oligopeptídeos/química , Osteogênese/fisiologia , Ácido Poliglutâmico/química , Ligação Proteica
14.
Pain ; 91(1-2): 123-30, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11240084

RESUMO

Oral transmucosal fentanyl citrate (OTFC); Actiq) is a drug delivery formulation used for management of breakthrough cancer pain. Previous studies with open-label comparisons indicated OTFC was more effective than patients' usual opioid for breakthrough pain. The objective of this study was to compare OTFC and morphine sulfate immediate release (MSIR) for management of breakthrough pain in patients receiving a fixed scheduled opioid regimen. This double-blind, double-dummy, randomized, multiple crossover study was conducted at 19 US university- and community-based hospitals and clinics and comprised 134 adult ambulatory cancer patients. Patients were receiving a fixed scheduled opioid regimen equivalent to 60-1000 mg/day oral morphine or 50-300 microg/h transdermal fentanyl, were using a 'successful' MSIR dose (15-60 mg) as defined by entry criteria, and were experiencing 1-4 episodes of breakthrough pain per day. In open-label fashion, OTFC was titrated such that a single unit (200-1600 microg) provided adequate pain relief with acceptable side effects. Successfully titrated patients entered the double-blind phase of the study and received ten prenumbered sets of randomized capsules and oral transmucosal units. Five sets were the successful OTFC dose paired with placebo capsules, and five sets were placebo OTFC paired with capsules containing the successful MSIR dose. Patients took one set of study medication for each episode of target breakthrough pain. Pain intensity (PI), pain relief (PR) and global performance of medication (GP) scores were recorded. Pain intensity differences (PID) were calculated and 15-min PID was the primary efficacy variable. Adverse events were recorded. Sixty-nine percent of patients (93/134) found a successful dose of OTFC. OTFC yielded outcomes (PI, PID, and PR) at all time points that were significantly better than MSIR. GP also favored OTFC and more patients opted to continue with OTFC than MSIR following the study. Somnolence, nausea, constipation, and dizziness were the most common drug-associated side effects. In conclusion, OTFC was more effective than MSIR in treating breakthrough cancer pain.


Assuntos
Analgésicos Opioides/uso terapêutico , Fentanila/uso terapêutico , Morfina/uso terapêutico , Neoplasias/tratamento farmacológico , Cuidados Paliativos , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fentanila/administração & dosagem , Fentanila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Morfina/administração & dosagem , Morfina/efeitos adversos , Neoplasias/fisiopatologia , Medição da Dor , Resultado do Tratamento
15.
J Histochem Cytochem ; 24(5): 668-73, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-58928

RESUMO

The location and characteristics of carbohydrate-containing structures within the intact sheath of Volvox were studied by 3,3'-diaminobenzidine tetrahydrochloride-osmium, colloidal iron, colloidal thorium, ruthenium red and periodic acid-silver methenamine staining. The sheath consists of external and internal fibrillar layers separated by a tripartite structure. The external layer reacts positively with 3,3'-diaminobenzidine tetrahydrochloride, colloidal iron, colloidal thorium and ruthenium red, indicating that it contains acid mucosaccharides. Staining in the external layer is abolished by Ba(OH)2 treatment. The tripartite structure and internal fibrillar layer contain periodic acid reactive groups which do not occur in the external layer. Under certain conditions, reactions between the cationic dyes and the internal material were also observed. It is postulated that the internal matrix of the sheath contains glycoproteins or a mixture of acid mucosaccharides and glycoproteins. Possible functions of the sheath material are discussed.


Assuntos
Carboidratos/análise , Eucariotos/ultraestrutura , Animais , Eucariotos/análise , Glutaral , Histocitoquímica , Microscopia Eletrônica , Coloração e Rotulagem , Tório
16.
J Pharm Sci ; 76(1): 56-9, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3585725

RESUMO

Quasi-elastic light scattering has been used for the sizing of a vesicle formulation. Porcine insulin was encapsulated in a vesicle preparation containing cholesterol, dipalmitoylphosphotidylcholine, digalactosyl digycerides, and dipalmitoylphosphotidylglycerol in a 40:40:15:5 ratio. The measurement requires less than 15 min to obtain mean size and distribution information and can be operated in a quality control environment. Advantages and limitations of quasi-elastic light scattering are described and this method is compared to electron microscopy and ultracentrifugation.


Assuntos
Química Farmacêutica , Tamanho da Partícula , Cromatografia em Gel , Luz , Microscopia Eletrônica , Veículos Farmacêuticos , Espalhamento de Radiação , Ultracentrifugação
17.
J Pharm Sci ; 75(9): 838-41, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3537276

RESUMO

A method for the determination of the amount of insulin in a vesicle formulation was developed. Samples were treated with anion exchange resin to quantitatively remove the insulin outside the vesicle walls. Encapsulated insulin was released from vesicles by disruption with a surfactant and the amount released was determined by reversed-phase HPLC. Recovery of insulin from the vesicle matrix was 99, 97, and 98% for vesicle solutions spiked with 1.0, 0.5, and 0.2 U/mL of insulin, respectively. The sample preparation steps resulted in removal of greater than 99.5% of the unencapsulated insulin; 98% recovery of the vesicles from the resin; 97% recovery of the encapsulated insulin from the resin; and greater than 99% disruption of the vesicles by the surfactant. Precision of the measurements for the amounts of total and encapsulated insulin was 2.7 and 3.3% relative standard deviations, respectively, for insulin levels of 0.7 U/mL.


Assuntos
Insulina/análise , Animais , Cromatografia Líquida de Alta Pressão , Insulina/administração & dosagem , Veículos Farmacêuticos , Suínos
18.
Laryngoscope ; 98(7): 721-5, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3386376

RESUMO

All admissions to the Shriner's Burn Institute in Galveston over a 5-year period were reviewed. One hundred of 1,092 patients admitted (9.2%) required airway support (endotracheal intubation or tracheostomy) for more than 24 hours. All clinical variables relating to general presentation and airway care were tabulated. Children who required open airway operations for resolution of acquired airway defects were analyzed separately. No predictive factors could be identified. Guidelines for optimal airway management in the burned child are reviewed.


Assuntos
Queimaduras/complicações , Intubação Intratraqueal/métodos , Insuficiência Respiratória/etiologia , Traqueostomia/métodos , Broncoscopia , Queimaduras/mortalidade , Queimaduras por Inalação/complicações , Criança , Pré-Escolar , Feminino , Humanos , Laringoscopia , Laringoestenose/etiologia , Laringoestenose/terapia , Masculino , Análise de Regressão , Respiração Artificial/métodos , Insuficiência Respiratória/terapia , Estudos Retrospectivos , Traqueostomia/instrumentação
19.
Arch Otolaryngol Head Neck Surg ; 113(1): 45-50, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3790284

RESUMO

The domain of this study is the reporting of statistical analyses in the otolaryngology literature during 1983 and 1984. Fewer than ten basic statistical procedures accounted for more than 90% of the statistical techniques reported. Implications for authors, journals, and educators are discussed. We offer suggestions for imparting statistical skills that may be helpful in curriculum design, residency training, and continuing medical education planning.


Assuntos
Otolaringologia , Publicações Periódicas como Assunto , Estatística como Assunto , Humanos , Métodos , Revisão por Pares
20.
Arch Otolaryngol Head Neck Surg ; 115(12): 1438-42, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2684248

RESUMO

Fine-needle aspiration biopsy is gaining acceptance as a clinically useful tool. We set out to evaluate the accuracy of fine-needle aspiration biopsy at our institution by measuring the interobserver variability in cytopathologic interpretation, and by measuring the agreement between cytopathologic and histologic diagnosis. In a prospective study, 253 aspirations were performed on head and neck masses by the otolaryngology service. Specimens were interpreted independently by two cytopathologists (V.J.S. and P.Z.), and interpretations were compared with the surgical histopathologic diagnosis when available. The interobserver variability between cytopathologists was 8% with a specificity of 96% and a sensitivity of 97%. We conclude that fine-needle aspiration biopsy is a safe and useful tool in the diagnosis of head and neck masses. In the diagnosis of epithelial cysts and squamous epithelial malignancies, fine-needle aspiration biopsy is as accurate as open biopsy.


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Biópsia por Agulha/economia , Carcinoma/epidemiologia , Carcinoma/patologia , Custos e Análise de Custo , Cistos/epidemiologia , Cistos/patologia , Interpretação Estatística de Dados , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Linfoma/epidemiologia , Linfoma/patologia , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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