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1.
Lupus ; 28(5): 642-650, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30907294

RESUMO

OBJECTIVES: The aims of this study are (1) to characterize factors influencing self-management behaviors and quality of life in adolescent and young adult (AYA) patients with childhood-onset systemic lupus erythematosus (cSLE) and (2) to identify barriers and facilitators of treatment adherence via focus groups. METHODS: AYAs with cSLE ages 12-24 years and primary caregivers of the adolescents participated in this study. Recruitment occurred during pediatric rheumatology clinic visits at a Midwestern children's hospital or the hospital's cSLE active clinic registry. Information about disease severity was obtained from patient health records. Pain and fatigue questionnaires were administered. Descriptive statistics were used to analyze data. RESULTS: Thirty-one AYA patients and caregivers participated in six focus groups. Ten major themes emerged from sessions; four were expressed both by the AYA and caregiver groups: knowledge deficits about cSLE, symptoms limiting daily function, specifically mood and cognition/learning, barriers and facilitators of adherence, and worry about the future. Themes unique to AYA participants included symptoms limiting daily functioning-pain/fatigue, self-care and management, impact on personal relationships, and health care provider communication/relationship. For caregiver groups unique themes included need for school advocacy, disruption of family schedule, and sense of normalcy for their adolescent. CONCLUSION: AYAs with cSLE face a lifelong disease characterized by pervasive pain, fatigue, organ damage, isolation-social and/or physical-and psycho-socioeducational challenges. This study confirmed that continued psychosocial support, health information education, adherence interventions, and personalized treatment plans are necessary to increase self-management and autonomy in AYAs with cSLE.


Assuntos
Cuidadores/psicologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Lúpus Eritematoso Sistêmico/psicologia , Autogestão , Adolescente , Idade de Início , Criança , Feminino , Grupos Focais , Humanos , Entrevistas como Assunto , Lúpus Eritematoso Sistêmico/terapia , Masculino , Ohio , Cooperação do Paciente , Qualidade de Vida , Sistema de Registros , Inquéritos e Questionários , Adulto Jovem
2.
J Geophys Res Space Phys ; 123(12): 10109-10123, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31008003

RESUMO

A simple Monte Carlo model is presented that considers the effects of spacecraft orbital sampling on the inferred distribution of magnetic flux ropes, generated through magnetic reconnection in the magnetotail current sheet. When generalized, the model allows the determination of the number of orbits required to constrain the underlying population of structures: It is able to quantify this as a function of the physical parameters of the structures (e.g., azimuthal extent and probability of generation). The model is shown adapted to the Hermean magnetotail, where the outputs are compared to the results of a recent survey. This comparison suggests that the center of Mercury's neutral line is located dawnward of midnight by 0 . 3 7 - 1 . 02 + 1 . 21 R M and that the flux ropes are most likely to be wide azimuthally (∼50% of the width of the Hermean tail). The downtail location of the neutral line is not self-consistent or in agreement with previous (independent) studies unless dissipation terms are included planetward of the reconnection site; potential physical explanations are discussed. In the future the model could be adapted to other environments, for example, the dayside magnetopause or other planetary magnetotails.

3.
J Geophys Res Space Phys ; 123(12): 10124-10138, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31008004

RESUMO

A Monte Carlo method of investigating the effects of placing selection criteria on the magnetic signature of in situ encounters with flux ropes is presented. The technique is applied to two recent flux rope surveys of MESSENGER data within the Hermean magnetotail. It is found that the different criteria placed upon the signatures will preferentially identify slightly different subsets of the underlying population. Quantifying the selection biases first allows the distributions of flux rope parameters to be corrected, allowing a more accurate estimation of the intrinsic distributions. This is shown with regard to the distribution of flux rope radii observed. When accounting for the selection criteria, the mean radius of Hermean magnetotail quasi-force-free flux ropes is found to be 58 9 - 269 + 273  km. Second, it is possible to weight the known identifications in order to determine a rate of recurrence that accounts for the presence of the structures that will not be identified. In the case of the Hermean magnetotail, the average rate of quasi-force-free flux ropes is found to 0.12 min-1 when selection effects are accounted for (up from 0.05 min-1 previously inferred from observations).

4.
J Geophys Res Space Phys ; 121(4): 2984-3005, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27867795

RESUMO

Reconnection within planetary magnetotails is responsible for locally energizing particles and changing the magnetic topology. Its role in terms of global magnetospheric dynamics can involve changing the mass and flux content of the magnetosphere. We have identified reconnection related events in spacecraft magnetometer data recorded during Cassini's exploration of Saturn's magnetotail. The events are identified from deflections in the north-south component of the magnetic field, significant above a background level. Data were selected to provide full tail coverage, encompassing the dawn and dusk flanks as well as the deepest midnight orbits. Overall 2094 reconnection related events were identified, with an average rate of 5.0 events per day. The majority of events occur in clusters (within 3 h of other events). We examine changes in this rate in terms of local time and latitude coverage, taking seasonal effects into account. The observed reconnection rate peaks postmidnight with more infrequent but steady loss seen on the dusk flank. We estimate the mass loss from the event catalog and find it to be insufficient to balance the input from the moon Enceladus. Several reasons for this discrepancy are discussed. The reconnection X line location appears to be highly variable, though a statistical separation between events tailward and planetward of the X line is observed at a radial distance of between 20 and 30RS downtail. The small sample size at dawn prevents comprehensive statistical comparison with the dusk flank observations in terms of flux closure.

5.
Rev Sci Instrum ; 86(7): 073102, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26233351

RESUMO

We have developed a cryogenic amplifier for the measurement of small current signals (10 fA-100 nA) from cryogenic optical detectors. Typically operated with gain near 10(7) V/A, the amplifier performs well from DC to greater than 30 kHz and exhibits noise level near the Johnson limit. Care has been taken in the design and materials to control heat flow and temperatures throughout the entire detector-amplifier assembly. A simple one-board version of the amplifier assembly dissipates 8 mW to our detector cryostat cold stage, and a two-board version can dissipate as little as 17 µW to the detector cold stage. With current noise baseline of about 10 fA/(Hz)(1/2), the cryogenic amplifier is generally useful for cooled infrared detectors, and using blocked impurity band detectors operated at 10 K, the amplifier enables noise power levels of 2.5 fW/(Hz)(1/2) for detection of optical wavelengths near 10 µm.

6.
J Geophys Res Space Phys ; 120(5): 3603-3617, 2015 05.
Artigo em Inglês | MEDLINE | ID: mdl-27570722

RESUMO

We present a case study of an event from 20 August (day 232) of 2006, when the Cassini spacecraft was sampling the region near 32 RS and 22 h LT in Saturn's magnetotail. Cassini observed a strong northward-to-southward turning of the magnetic field, which is interpreted as the signature of dipolarization of the field as seen by the spacecraft planetward of the reconnection X line. This event was accompanied by very rapid (up to ~1500 km s-1) thermal plasma flow toward the planet. At energies above 28 keV, energetic hydrogen and oxygen ion flow bursts were observed to stream planetward from a reconnection site downtail of the spacecraft. Meanwhile, a strong field-aligned beam of energetic hydrogen was also observed to stream tailward, likely from an ionospheric source. Saturn kilometric radiation emissions were stimulated shortly after the observation of the dipolarization. We discuss the field, plasma, energetic particle, and radio observations in the context of the impact this reconnection event had on global magnetospheric dynamics.

7.
Biomater Sci ; 2(11): 1672-1682, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25346848

RESUMO

Embryonic stem (ES) cells can be differentiated into many neural cell types that hold great potential as cell replacement therapies following spinal cord injury (SCI). Coupling stem cell transplantation with biomaterial scaffolds can produce a unified combination therapy with several potential advantages including enhanced cell survival, greater transplant retention, reduced scarring, and improved integration at the transplant/host interface. Undesired cell types, however, are commonly present in ES-cell derived cultures due to the limited efficiency of most ES cell induction protocols. Heterogeneous cell populations can confound the interaction between the biomaterial and specific neural populations leading to undesired outcomes. In particular, biomaterials scaffolds may enhance tumor formation by promoting survival and proliferation of undifferentiated ES cells that can persist after induction. Methods for purification of specific ES cell-derived neural populations are necessary to recognize the full potential of combination therapies involving biomaterials and ES cell-derived neural populations. We previously developed a method for enriching ES cell-derived progenitor motor neurons (pMNs) induced from mouse ES cells via antibiotic selection and showed that the enriched cell populations are depleted of pluripotent stem cells. In this study, we demonstrate the survival and differentiation of enriched pMNs within three dimensional (3D) fibrin scaffolds in vitro and when transplanted into a sub-acute dorsal hemisection model of SCI into neurons, oligodendrocytes and astrocytes.

8.
Steroids ; 81: 31-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24269736

RESUMO

Two populations of cells within the hypothalamus exert opposite actions on food intake: proopiomelanocortin (POMC) neurons decrease it, while neuropeptide Y (NPY)/agouti-related peptide (AgRP) neurons increase it. 17ß-Estradiol (E2) is a potent anorexigenic hormone that exerts both genomic and non-genomic, rapid actions on these metabolic neurons. This review focuses on the rapid membrane effects of E2 in both POMC and NPY/AgRP neurons and how these combined effects mediate the anorexigenic effects of this steroid.


Assuntos
Ingestão de Alimentos , Estradiol/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Proteína Relacionada com Agouti/metabolismo , Animais , Regulação da Temperatura Corporal , Metabolismo Energético , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Retroalimentação Fisiológica , Homeostase , Humanos , Hipotálamo/citologia , Neurônios/efeitos dos fármacos , Neuropeptídeo Y/metabolismo , Pró-Opiomelanocortina , Transdução de Sinais
9.
Am J Physiol Endocrinol Metab ; 305(5): E632-40, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23820624

RESUMO

Besides its quintessential role in reproduction, 17ß-estradiol (E2) is a potent anorexigenic hormone. E2 and the selective Gq-coupled membrane estrogen receptor (Gq-mER) ligand STX rapidly increase membrane excitability in proopiomelanocortin (POMC) neurons by desensitizing the coupling of GABAB receptors to G protein-coupled inwardly rectifying K(+) channels (GIRKs), which upon activation elicit a hyperpolarizing outward current. However, it is unknown whether E2 and STX can modulate GABAB signaling in neuropeptide Y (NPY)/agouti-related peptide (AgRP) neurons. We used single-cell RT-PCR and whole cell patch clamping with selective pharmacological reagents to show that NPY/AgRP cells of mice express the GABAB-R1 and -R2 receptors and are hyperpolarized by the GABAB agonist baclofen in an E2-dependent manner. In males, E2 rapidly attenuated the coupling of GABAB receptors to GIRKs, which was blocked by the general PI3K inhibitors wortmannin and LY-294002 or the selective p110ß subunit inhibitor TGX-221. The ERα-selective agonist propyl pyrazole triol mimicked the effects of E2. STX, in contrast, enhanced the GABAB response in males, which was abrogated by the estrogen receptor (ER) antagonist ICI 182,780. In gonadectomized mice of both sexes, E2 enhanced or attenuated the GABAB response in different NPY/AgRP cells. Coperfusing wortmannin with E2 or simply applying STX always enhanced the GABAB response. Thus, in NPY/AgRP neurons, activation of the Gq-mER by E2 or STX enhances the GABAergic postsynaptic response, whereas activation of ERα by E2 attenuates it. These findings demonstrate a clear functional dichotomy of rapid E2 membrane-initiated signaling via ERα vs. Gq-mER in a CNS neuron vital for regulating energy homeostasis.


Assuntos
Acrilamidas/farmacologia , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Receptores de GABA-B/metabolismo , Acrilamidas/metabolismo , Animais , Baclofeno/farmacologia , Estradiol/metabolismo , Feminino , Agonistas dos Receptores de GABA-B/farmacologia , Cobaias , Masculino , Camundongos , Camundongos Transgênicos , Técnicas de Patch-Clamp , Transdução de Sinais
10.
J Res Natl Inst Stand Technol ; 118: 396-402, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26401440

RESUMO

We report a measurement of lunar spectral irradiance with an uncertainty below 1 % from 420 nm to 1000 nm. This measurement uncertainty meets the stability requirement for many climate data records derived from satellite images, including those for vegetation, aerosols, and snow and ice albedo. It therefore opens the possibility of using the Moon as a calibration standard to bridge gaps in satellite coverage and validate atmospheric retrieval algorithms. Our measurement technique also yields detailed information about the atmosphere at the measurement site, suggesting that lunar observations are a possible solution for aerosol monitoring during the polar winter and can provide nighttime measurements to complement aerosol data collected with sun photometers. Our measurement, made with a novel apparatus, is an order of magnitude more accurate than the previous state-of-the-art and has continuous spectral coverage, removing the need to interpolate between filter passbands.

11.
Int J Sports Med ; 33(8): 647-53, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22510799

RESUMO

There are no studies which have examined the differences in kinetics between lateral plyometric exercises and the selection of these exercises is largely based on the experience and observation of coaches. This study aimed to compare ground reaction forces (GRF) and contact times (GCT) between 2 lateral plyometric exercises: lateral alternative leg hopping (HOP), and speed lateral footwork (SPEED). 16 professional male soccer players (age: 24.6±5.5 years; and BMI: 21.7±2.2 kg.m - 2) participated in this within-participant repeated measures study. 3-dimensional GRF data were measured by force platform. Our study revealed significant differences between the 2 lateral plyometric exercises in all kinetics parameters (F=573.7, P<0.01). HOP produced significantly longer GCT (0.45 s vs. 0.23 s, P<0.01, large effect), significantly higher values (P<0.05, large effect) in peak force (3.31 vs. 2.47 Body Weight [BW]), peak rate of force development (0.94 vs. 0.29 BW/s), and impulse (0.76 vs. 0.31 BW.s) except for peak force in the medial-lateral (P<0.05, medium effect) and impulse in the anterio-posterior direction (not significant, small effect). Therefore, SPEED is an exercise that aims to increase step frequency because of its short GCT (< 0.25 s) while HOP increases leg strength and power.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Exercício Pliométrico/métodos , Futebol/fisiologia , Adulto , Humanos , Cinética , Masculino , Reprodutibilidade dos Testes
12.
Am J Physiol Endocrinol Metab ; 302(11): E1399-406, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22436698

RESUMO

Hypothalamic proopiomelanocortin (POMC) neurons are controlled by many central signals, including serotonin. Serotonin increases POMC activity and reduces feeding behavior via serotonion [5-hydroxytryptamine (5-HT)] receptors by modulating K(+) currents. A potential K(+) current is the M-current, a noninactivating, subthreshold outward K(+) current. Previously, we found that M-current activity was highly reduced in fasted vs. fed states in neuropeptide Y neurons. Because POMC neurons also respond to energy states, we hypothesized that fasting may alter the M-current and/or its modulation by serotonergic input to POMC neurons. Using visualized-patch recording in neurons from fed male enhanced green fluorescent protein-POMC transgenic mice, we established that POMC neurons expressed a robust M-current (102.1 ± 6.7 pA) that was antagonized by the selective KCNQ channel blocker XE-991 (40 µM). However, the XE-991-sensitive current in POMC neurons did not differ between fed and fasted states. To determine if serotonin suppresses the M-current via the 5-HT(2C) receptor, we examined the effects of the 5-HT(2A)/5-HT(2C) receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) on the M-current. Indeed, DOI attenuated the M-current by 34.5 ± 6.9% and 42.0 ± 5.3% in POMC neurons from fed and fasted male mice, respectively. In addition, the 5-HT(1B)/5-HT(2C) receptor agonist m-chlorophenylpiperazine attenuated the M-current by 42.4 ± 5.4% in POMC neurons from fed male mice. Moreover, the selective 5-HT(2C) receptor antagonist RS-102221 abrogated the actions of DOI in suppressing the M-current. Collectively, these data suggest that although M-current expression does not differ between fed and fasted states in POMC neurons, serotonin inhibits the M-current via activation of 5-HT(2C) receptors to increase POMC neuronal excitability and, subsequently, reduce food intake.


Assuntos
Hipotálamo/metabolismo , Canais de Potássio KCNQ/antagonistas & inibidores , Neurônios/metabolismo , Pró-Opiomelanocortina/fisiologia , Receptor 5-HT2C de Serotonina/metabolismo , Anfetaminas/farmacologia , Animais , Antracenos/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Jejum/fisiologia , Hipotálamo/citologia , Hipotálamo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Piperazinas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Receptor 5-HT2C de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Compostos de Espiro/farmacologia , Sulfonamidas/farmacologia
13.
J Neuroendocrinol ; 24(5): 737-47, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22172059

RESUMO

Gonadotrophin-releasing hormone (GnRH) agonists are used to treat gonadal steroid-dependent disorders in humans and to contracept animals. These agonists are considered to work by desensitising gonadotrophs to GnRH, thereby suppressing follicle-stimulating hormone (FSH) and luteinising hormone (LH) secretion. It is not known whether changes occur in the cellular composition of the pituitary gland after chronic GnRH agonist exposure. Adult male Sprague-Dawley rats were treated with a sham, deslorelin, or deslorelin plus testosterone implant for 41.0 ± 0.6 days. In a second experiment, rats were castrated and treated with deslorelin and/or testosterone. Pituitary sections were labelled immunocytochemically for FSHß and LHß, or gonadotrophin α subunit (αGSU). Deslorelin suppressed testis weight by two-thirds and reduced plasma FSH and LH in intact rats. Deslorelin decreased the percentage of gonadotrophs, although the effect was specific to the FSHß-immunoreactive (-ir) cells. Testosterone did not reverse the deslorelin-induced reduction in the overall gonadotroph population. However, in the presence of testosterone, the proportion of gonadotrophs that was FSHß-ir increased in the remaining gonadotrophs. There was no effect of treatment on the total LHß-ir cell population, although the loss of FSHß in bi-hormonal cells increased the proportion of mono-hormonal LHß-ir gonadotrophs. The castration-induced plasma LH and FSH increases were suppressed by deslorelin, testosterone or both. Castration increased both LH-ir and FSH-ir without increasing the overall gonadotroph population, thus increasing the proportion of bi-hormonal cells. Deslorelin suppressed these increases. Testosterone increased FSH-ir in deslorelin-treated castrate rats. Deslorelin did not affect αGSU immunoreactivity, suggesting that the gonadotroph population per se is not eliminated by deslorelin, although the ability of gonadotrophs to synthesise FSHß is compromised. We hypothesise that the FSH dominant suppression may be central to the long-term contraceptive efficacy of deslorelin in the male.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Pamoato de Triptorrelina/análogos & derivados , Animais , Regulação para Baixo/efeitos dos fármacos , Hormônio Foliculoestimulante/sangue , Gonadotrofos/efeitos dos fármacos , Gonadotrofos/metabolismo , Hormônio Liberador de Gonadotropina/agonistas , Antagonistas de Hormônios/farmacologia , Imuno-Histoquímica , Masculino , Orquiectomia , Tamanho do Órgão/efeitos dos fármacos , Hipófise/anatomia & histologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Ratos , Ratos Sprague-Dawley , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testículo/metabolismo , Fatores de Tempo , Pamoato de Triptorrelina/farmacologia
14.
Neuroscience ; 192: 675-88, 2011 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-21763405

RESUMO

The serotonin system responds to the ovarian steroids, estradiol (E) and progesterone (P), in women and female animal models. In macaques, ovarian steroid administration to ovariectomized (Ovx) individuals improves serotonin neural function through actions on pivotal serotonin-related genes and proteins, such as TPH2 (tryptophan hydroxylase 2), SERT (serotonin reuptake transporter), and the 5HT1A autoreceptor. In addition, ovarian steroid administration reduces gene and protein expression in the caspase-independent pathway and reduces DNA fragmentation in serotonin neurons. This study examines the hypothesis that long-term ovariectomy will lead to a loss of serotonin neurons and compromised gene expression in serotonin neurons. Female Japanese macaques were ovariectomized or tubal ligated (n=5/group) at 3 years of age and returned to their natal troop. After 3 years, the animals were collected, administered a fenfluramine challenge to determine global serotonin availability, and then euthanized. Fev, TPH2, SERT, and 5HT1A expression were examined with digoxigenin in situ hybridization (ISH) and quantitative image analysis. Cell number, positive pixel area, and average pixel density were determined. In the Ovx group, Fev, TPH2, SERT, and 5HT1A showed a significant decease in average and total cell number and positive pixel area. The reduction in Fev-positive neurons suggests that there were fewer serotonin neurons in Ovx animals compared to ovary-intact animals. The decrease in TPH2 in the Ovx animals was consistent with earlier results in 5-month Ovx animals, but it may be due to the decrease in cell number rather than a decrease in expression on an individual cell basis. The decrease in SERT and 5HT1A in long-term Ovx differed from previous studies in short-term Ovx. In summary, long-term ovarian steroid loss resulted in fewer serotonin neurons and overall lower Fev, TPH2, SERT, and 5HT1A gene expression. This may be due to serotonin cell death or to a negative impact on a long-term developmental process in young female macaques.


Assuntos
Encéfalo/metabolismo , Expressão Gênica/fisiologia , Neurônios/metabolismo , Serotonina/metabolismo , Animais , Contagem de Células , Feminino , Hibridização In Situ , Macaca , Ovariectomia , Receptores 5-HT1 de Serotonina/biossíntese , Proteínas da Membrana Plasmática de Transporte de Serotonina/biossíntese , Triptofano Hidroxilase/biossíntese
15.
Lett Appl Microbiol ; 47(3): 148-52, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19552777

RESUMO

AIMS: To compare rhamnose MacConkey agar supplemented with cefixime and tellurite (CT-RMac) and tryptone bile X-glucuronide (TBX) agars as isolation media for Vero cytotoxin-producing Escherichia coli (VTEC) serogroup O26 from animal faeces. METHODS AND RESULTS: Nine VTEC O26 were isolated from sheep faeces; out of which six were isolated only on CT-RMac and one was isolated only on TBX. One hundred and twelve VTEC O26 were isolated from calf faeces; out of which 97% were from CT-RMac and 52% were from TBX. In a study of E. coli O26 strains, 84% of VT-positive O26 did not ferment rhamnose when compared with 16% of VT-negative O26. VT-positive (19%) and VT-negative (39%) E. coli O26 strains did not grow on CT-RMac agar. CONCLUSIONS: It is important to consider that VTEC O26 strains either may ferment rhamnose or may be sensitive to the CT supplement of CT-RMac agar. SIGNIFICANCE AND IMPACT OF THE STUDY: This work compares CT-RMac and TBX agars as isolation medium for VTEC O26 from Scottish animal faeces and highlights that VTEC O26 may be missed if only CT-RMac agar is used.


Assuntos
Bovinos/microbiologia , Cefixima/farmacologia , Meios de Cultura , Fezes/microbiologia , Ramnose/metabolismo , Ovinos/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Telúrio/farmacologia , Ágar , Animais , Fermentação , Escherichia coli Shiga Toxigênica/metabolismo
16.
Appl Environ Microbiol ; 72(11): 7260-3, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16980429

RESUMO

The sensitivity of a test for cattle shedding Escherichia coli serogroup O26 was estimated using several fecal pats artificially inoculated at a range of concentrations with different E. coli O26 strains. The test involves the enrichment of fecal microflora in buffered peptone water, the selective concentration of E. coli O26 using antibody-coated immunomagnetic-separation beads, the identification of E. coli colonies on Chromocult tryptone bile X-glucuronide agar, and confirmation of the serogroup with E. coli serogroup O26-specific antisera using slide agglutination. The effective dose of E. coli O26 for an 80% test sensitivity (ED(80)) was 1.0 x 10(4) CFU g(-1) feces (95% confidence interval, 4.7 x 10(3) to 2.4 x 10(4)). Differences in test sensitivity between different E. coli O26 strains and fecal pats were also observed. Individual estimates of ED(80) for each strain and fecal pat combination ranged from 4.2 x 10(2) to 4.8 x 10(5) CFU g(-1). These results suggest that the test is useful for identifying individuals shedding a large number of E. coli O26 organisms or, if an appropriate number of individuals in a herd are sampled, for identifying affected herds. The study also provides a benchmark estimate of sensitivity that can be used to compare alternative tests for E. coli O26 and a methodological approach that can be applied to tests for other pathogenic members of the Enterobacteriaceae and other sample types.


Assuntos
Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Separação Imunomagnética/métodos , Animais , Técnicas Bacteriológicas , Bovinos , Contagem de Colônia Microbiana , Meios de Cultura , Reservatórios de Doenças , Escherichia coli/classificação , Infecções por Escherichia coli/microbiologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
17.
Appl Environ Microbiol ; 72(1): 653-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16391103

RESUMO

A national survey was conducted to determine the prevalence of Escherichia coli O26, O103, O111, and O145 in feces of Scottish cattle. In total, 6,086 fecal pats from 338 farms were tested. The weighted mean percentages of farms on which shedding was detected were 23% for E. coli O26, 22% for E. coli O103, and 10% for E. coli O145. The weighted mean prevalences in fecal pats were 4.6% for E. coli O26, 2.7% for E. coli O103, and 0.7% for E. coli O145. No E. coli O111 was detected. Farms with cattle shedding E. coli serogroup O26, O103, or O145 were widely dispersed across Scotland and were identified most often in summer and autumn. However, on individual farms, fecal shedding of E. coli O26, O103, or O145 was frequently undetectable or the numbers of pats testing positive were small. For serogroup O26 or O103 there was clustering of positive pats within management groups, and the presence of an animal shedding one of these serogroups was a positive predictor for shedding by others, suggesting local transmission of infection. Carriage of vtx was rare in E. coli O103 and O145 isolates, but 49.0% of E. coli O26 isolates possessed vtx, invariably vtx1 alone or vtx1 and vtx2 together. The carriage of eae and ehxA genes was highly associated in all three serogroups. Among E. coli serogroup O26 isolates, 28.9% carried vtx, eae, and ehxA-a profile consistent with E. coli O26 strains known to cause human disease.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/classificação , Fatores de Virulência/metabolismo , Criação de Animais Domésticos , Animais , Bovinos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Fezes/microbiologia , Prevalência , Escócia , Sorotipagem
18.
J Invertebr Pathol ; 88(1): 27-33, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15707866

RESUMO

The mosquito-larvicidal binary toxin produced by Bacillus sphaericus is composed of BinB and BinA, which have calculated molecular weights of 51.4 and 41.9 kDa, respectively. NaOH extracts of B. sphaericus spores were analyzed using SDS-PAGE. Stained gels showed bands with molecular weights corresponding to those of BinB and BinA as well as two additional bands at 110 and 125 kDa. The matrix-assisted laser desorption/ionization mass spectrum of the purified 110 and 125 kDa bands showed two peaks at 104,160 and 87,358 Da that are assigned to dimers of BinB and BinA, respectively. Mass spectral analysis of trypsin-digested 110 and 125 kDa bands showed peaks at 51,328, 43,523, 43,130, and 40,832 Da that assigned to undigested BinB, two forms of digested BinB and digested BinA, respectively. Dynamic light scattering studies showed a solution of the purified 110 and 125 kDa bands was comprised almost entirely (99.6% of total mass) of a particle with a hydrodynamic radius of 5.6+/-1.2 nm and a calculated molecular weight of 186+/-38 kDa. These data demonstrate that the binary toxin extracted from B. sphaericus spores can exist in solution as an oligomer containing two copies each of BinB and BinA.


Assuntos
Bacillus/fisiologia , Toxinas Bacterianas/química , Controle Biológico de Vetores , Esporos/química , Animais , Bacillus/química , Toxinas Bacterianas/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
19.
Clin Biomech (Bristol, Avon) ; 20(3): 330-5, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15698707

RESUMO

BACKGROUND: Impairments in balance performance are a commonly accepted risk factor for falling in older people. Since there is a higher reported incidence of falling in women, it is of interest to test whether this correlates with poorer balance performance in women than men at the time of retirement in order to plan health promotional strategies. The purpose of this study was to investigate whether any gender differences exist in balance performance in people approaching retirement age. METHODS: Ninety-seven healthy volunteers (44 males, 53 females) planning to retire shortly were enrolled in the study (age range 50-67 years). Balance assessments during quiet standing were performed under various conditions; feet together eyes open, feet together eyes closed and single limb stance eyes open. The range of centre of pressure displacement in both the anterior-posterior and medial-lateral planes was collected for each task using a force platform. FINDINGS: For several of the balance tasks the men exhibited a statistically significant larger range of centre of pressure displacement than the women (P<0.01). However, after normalising the data for height, no gender differences were seen. Over half of the group failed to complete all three single limb stance trials on both limbs. INTERPRETATION: When the data was normalised for height, no differences were found in static balance performance between men and women of retirement age. A number of participants demonstrated balance impairments whilst performing the single limb stance likely to affect functional activities. Health promotional messages should be targeted equally at men and women.


Assuntos
Movimento/fisiologia , Exame Físico/métodos , Equilíbrio Postural/fisiologia , Postura/fisiologia , Aposentadoria , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Fatores Sexuais , Análise e Desempenho de Tarefas
20.
Int J Obes (Lond) ; 29(2): 244-50, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15654361

RESUMO

OBJECTIVE: To investigate the effects of chronic stress on weight changes and related behavioral changes in parents with a child who had just been diagnosed with cancer compared to parents with healthy children. DESIGN: Longitudinal case-control study with assessments occurring over a three-month period following the child's diagnosis of cancer. SUBJECTS: In total, 49 parents of healthy children and 49 parents of cancer patients aged 19-58. MEASUREMENTS: Body weight, diet, physical activity, self-reported mood and stress. RESULTS: Parents of cancer patients were more likely to gain weight, and experienced significantly greater weight gain over the 3 months than parents of healthy children. The magnitude of weight gain was related to the degree of psychological distress that the parents experienced. Parents of cancer patients reported lower levels of physical activity and lower caloric intake than parents of healthy children, with the most marked differences between groups occurring in the area of physical activity. CONCLUSION: Findings suggest that a major stressor, such as a child's diagnosis of cancer, is associated with weight gain. Further research is needed to determine how long these weight gains persist and whether other types of stress also produce weight gains. Such studies should focus not only on the effect of stress on eating behavior but also on physical activity.


Assuntos
Neoplasias/psicologia , Pais/psicologia , Estresse Psicológico/fisiopatologia , Aumento de Peso , Adolescente , Adulto , Peso Corporal , Estudos de Casos e Controles , Criança , Pré-Escolar , Doença Crônica , Dieta , Ingestão de Energia , Saúde da Família , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Atividade Motora
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