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1.
Phys Rev Lett ; 130(16): 166703, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37154642

RESUMO

Spiral spin liquids are an exotic class of correlated paramagnets with an enigmatic magnetic ground state composed of a degenerate manifold of fluctuating spin spirals. Experimental realizations of the spiral spin liquid are scarce, mainly due to the prominence of structural distortions in candidate materials that can trigger order-by-disorder transitions to more conventionally ordered magnetic ground states. Expanding the pool of candidate materials that may host a spiral spin liquid is therefore crucial to realizing this novel magnetic ground state and understanding its robustness against perturbations that arise in real materials. Here, we show that the material LiYbO_{2} is the first experimental realization of a spiral spin liquid predicted to emerge from the J_{1}-J_{2} Heisenberg model on an elongated diamond lattice. Through a complementary combination of high-resolution and diffuse neutron magnetic scattering studies on a polycrystalline sample, we demonstrate that LiYbO_{2} fulfills the requirements for the experimental realization of the spiral spin liquid and reconstruct single-crystal diffuse neutron magnetic scattering maps that reveal continuous spiral spin contours-a characteristic experimental hallmark of this exotic magnetic phase.

2.
J Dairy Sci ; 106(9): 5880-5895, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37474366

RESUMO

The use of qualitative research in dairy science has increased considerably in recent years, providing the opportunity to inform research and practice. This review aims to enhance the accessibility of qualitative research among a range of audiences and specifically: (1) provide an overview of what qualitative research is and the value it can bring to scientific inquiries in the dairy context, (2) illustrate the emergence of qualitative dairy science research in the past 15 to 20 years, (3) outline the role of the researcher and key philosophical assumptions underlying qualitative research, (4) describe qualitative research approaches and methods used in dairy science research, and (5) highlight key aspects of qualitative inquiry used to ensure research trustworthiness. Qualitative approaches in dairy science enable researchers to understand myriad topics including stakeholder relationships, decision-making, and behaviors regarding dairy cattle management, animal welfare, and disease prevention and control measures. Approaches that were used often for qualitative data collection were individual interviews and focus groups, and variations of thematic analysis were common analytical frameworks. To assess public values, attitudes, and perceptions, mixed methods questionnaires that combined quantitative data with qualitative data from open-ended questions were used regularly. Although still used infrequently, action research and participatory approaches have the potential to bridge the research-implementation gap by facilitating group-based learning and on-farm changes. Some publications described the philosophical assumptions inherent to qualitative research, and many authors included reflexivity and positionality statements. Although a comprehensive description of strategies to meet trustworthiness criteria for qualitative research was uncommon, many publications mentioned certain aspects of trustworthiness, such as member checking, researcher triangulation, and the recording of reflexive notes. Qualitative research has been used to deepen our understanding of phenomena relevant to the dairy sector and has opened the door for a broad array of new opportunities. In addition to having merit on its own, qualitative research can guide, inform, and expand on quantitative research, and an understanding of the core pillars of qualitative research can foster interdisciplinary collaborations.


Assuntos
Atitude , Bovinos , Animais , Pesquisa Qualitativa , Grupos Focais , Fazendas
3.
J Dairy Sci ; 105(4): 3248-3268, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35094864

RESUMO

Early cow-calf separation followed by individual housing of calves is standard practice on dairy farms. However, a growing body of evidence suggests that as awareness grows the public will oppose these practices, which could compromise the dairy industry's social license. Despite disagreement among different stakeholders over weighting and evaluations of effects of early separation (e.g., distress response, disease risk), recent systematic reviews indicate that there is little scientific evidence supporting this practice. The acceptability of alternative cow-calf management systems is unknown. We used a mixed methods survey with a convenience sample of 307 Canadians plus a representative sample of 1,487 Americans to investigate perceptions of these systems, examining the effects of providing social or foster cow contact following early separation or not separating cow-calf pairs. Attitudes and perceptions of animal welfare were more positive (on a 7-point scale where 1 is most negative, 7 is most positive, and 4 is a neutral midpoint) toward the system where calves were not separated from the cow (mean ± SE; 5.8 ± 0.07; 5.7 ± 0.07), compared with systems in which the calf was separated and individually housed (3.6 ± 0.07; 3.4 ± 0.07), separated and group housed (3.7 ± 0.07; 3.4 ± 0.07), or separated and kept with a foster cow (3.8 ± 0.07; 3.6 ± 0.07). Participants were consistent in their attitudes toward and perceptions of animal welfare within the system, suggesting that participants took a holistic and value-oriented approach to cow-calf management regarding separation. These results, in combination with many participants' concern for the importance of the mother cow-calf relationship and perceptions that severing of this bond was a breach of standard of care, suggest that there may be low acceptance of any cow-calf management system involving early separation as such systems are unlikely to resonate with underlying values.


Assuntos
Bem-Estar do Animal , Indústria de Laticínios , Animais , Atitude , Canadá , Bovinos , Indústria de Laticínios/métodos , Fazendas , Feminino , Humanos
4.
Phys Rev Lett ; 124(8): 087206, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32167347

RESUMO

We report time-of-flight neutron spectroscopy and neutron and x-ray diffraction studies of the 5d^{2} double perovskite magnets, Ba_{2}MOsO_{6} (M=Zn,Mg,Ca). These materials host antiferromagnetically coupled 5d^{2} Os^{6+} ions decorating a face-centered cubic (fcc) lattice and are found to remain cubic down to the lowest temperatures. They all exhibit thermodynamic anomalies consistent with a single phase transition at a temperature T^{*}, and a gapped magnetic excitation spectrum with spectral weight concentrated at wave vectors typical of type-I antiferromagnetic orders. However, while muon spin resonance experiments show clear evidence for time-reversal symmetry breaking below T^{*}, we observe no corresponding magnetic Bragg scattering signal. These results are shown to be consistent with ferro-octupolar symmetry breaking below T^{*}, and are discussed in the context of other 5d double perovskite magnets and theories of exotic orders driven by multipolar interactions.

5.
Phys Rev Lett ; 120(13): 137201, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29694199

RESUMO

Excitations in a spin ice behave as magnetic monopoles, and their population and mobility control the dynamics of a spin ice at low temperature. CdEr_{2}Se_{4} is reported to have the Pauling entropy characteristic of a spin ice, but its dynamics are three orders of magnitude faster than the canonical spin ice Dy_{2}Ti_{2}O_{7}. In this Letter we use diffuse neutron scattering to show that both CdEr_{2}Se_{4} and CdEr_{2}S_{4} support a dipolar spin ice state-the host phase for a Coulomb gas of emergent magnetic monopoles. These Coulomb gases have similar parameters to those in Dy_{2}Ti_{2}O_{7}, i.e., dilute and uncorrelated, and so cannot provide three orders faster dynamics through a larger monopole population alone. We investigate the monopole dynamics using ac susceptometry and neutron spin echo spectroscopy, and verify the crystal electric field Hamiltonian of the Er^{3+} ions using inelastic neutron scattering. A quantitative calculation of the monopole hopping rate using our Coulomb gas and crystal electric field parameters shows that the fast dynamics in CdEr_{2}X_{4} (X=Se, S) are primarily due to much faster monopole hopping. Our work suggests that CdEr_{2}X_{4} offer the possibility to study alternative spin ice ground states and dynamics, with equilibration possible at much lower temperatures than the rare earth pyrochlore examples.

6.
J Dairy Sci ; 101(8): 7463-7470, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29803424

RESUMO

In herds with typical moderate to low within-herd prevalence, testing for Mycobacterium avium ssp. paratuberculosis (MAP), the infectious agent of Johne's disease, will be more cost-effective if individual fecal samples are cultured in composite pools. However, sensitivity to classify a pool containing 1 or more positive individual samples as positive may depend on pool size and number of individual positive samples within a pool. Fecal samples collected from 994 dairy cows sampled at slaughter were cultured to detect MAP. Culturing was done both individually and as composite pooled samples using the TREK ESP Culture System II broth medium (Thermo Fisher Scientific, Trek Diagnostic Systems Inc., Cleveland, OH). Composite samples consisted of pools containing feces from 3, 5, 8, 10, or 15 cows. The number of individual fecal culture-positive cows within each pool ranged from 0 to 4. Culture of individual fecal samples detected MAP in 36 (3.6%) of the 994 cows. Individual samples that were detected within the first 50 d by TREK ESP Culture System II were more likely to lead to a positive pool result. In total, 840 pooled fecal samples were examined for presence of MAP, and of those, 272 pools actually contained feces from fecal culture-positive cows. The crude sensitivity (proportion of pools that contained at least 1 fecal-positive cow that tested positive) for pools of 3, 5, 8, 10, and 15 was 47, 67, 44, 59, and 39%, respectively. Across pools, an increase of the number of fecal culture-positive samples from 1 to 2 enhanced overall crude sensitivity from 44 to 71%. However, sensitivity did not further increase for pools with 3 or 4 fecal culture-positive samples (63 and 60%, respectively). Additionally, a simulation analysis assessing probability of pooled fecal samples being positive in herds of 50 and 100 cows was conducted. The simulation assumed that 1, 2, or 5 cows per herd were MAP fecal culture-positive and that pools of 5 and 10 were used. This low-prevalence herd simulation indicated that weighted mean herd probabilities of detecting a positive herd ranged between 52 and 99.3%, with the lowest probability for pools of 10 with 1 positive cow in the herd and the highest probability for pools of 5 with 5 positive cows in the herd. However, overall, pools of 5 and 10 had similar diagnostic capabilities, enabling cost savings by utilizing pools of 10.


Assuntos
Doenças dos Bovinos/diagnóstico , Fezes/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Paratuberculose/microbiologia , Prevalência
7.
Pharmazie ; 73(5): 260-263, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29724290

RESUMO

Medicininal compounds and their metabolites are known to end up in sewerage and may slip through the cleaning process. Azole antimycotics are frequently used in hospitals, in particular for patients with cancer or immunosuppression. The aim of the study was to determine whether measurable azole antimycotic concentrations were introducted in the sewarage drain of an acute care hospital with special interest in oncology and hematology and the extent of removal of antimycotics by the sewerage treatment plant. For this, the concentrations of three commonly used azole antimycotics were measured in the effluent of the sewerage drain at the University Hospital Dresden, as well as in the influent and effluent of the main sewerage treatment plant of the city. To extrapolate the theoretical influent to the sewerage treatment plant, prescription from the regio`s main health insurance the AOK Sachsen and the hospital consumption data were used. Measurable concentrations were obtained for fluconazole and ketoconazole in the influent and effluent of the sewerage treatment plant. Voriconazole's concentrations were under the lower limit of quantification. To determine the azole clearance of the treatment plant a sludge sample was investigated. Sufficient clearance was detected for ketoconazole but not for fluconazole. The consumption and prescription rates were collected and correlated with the measured concentrations. In result, only fluconazole's concentrations provided a good match with the prescription and consumption data.


Assuntos
Antifúngicos/química , Azóis/química , Esgotos/química , Antifúngicos/análise , Azóis/análise , Monitoramento Ambiental/métodos , Alemanha , Hospitais Urbanos , Habitação , Projetos Piloto , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
8.
Phys Rev Lett ; 118(5): 055701, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211724

RESUMO

In this Letter we report high-resolution synchrotron x-ray powder diffraction and transmission electron microscope analysis of Mn-substituted LaFeAsO samples, demonstrating that a static incommensurate modulated structure develops across the low-temperature orthorhombic phase, whose modulation wave vector depends on the Mn content. The incommensurate structural distortion is likely originating from a charge-density-wave instability, a periodic modulation of the density of conduction electrons associated with a modulation of the atomic positions. Our results add a new component in the physics of Fe-based superconductors, indicating that the density wave ordering is charge driven.

9.
Int Psychogeriatr ; 29(11): 1857-1868, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28780910

RESUMO

BACKGROUND: Older people have a higher risk of drug-related problems (DRPs). However, little is known about the prevalence of DRPs in community-dwelling people who screened positive for dementia. Our study aimed to determine (1) the prevalence and types of DRPs and (2) the socio-demographic and clinical variables associated with DRPs in people screened positive for dementia in primary care. METHODS: The Dementia: life- and person-centered help in Mecklenburg-Western Pomerania (DelpHi-MV) study is a general practitioner (GP)-based cluster-randomized controlled intervention study to implement and evaluate an innovative concept of collaborative dementia care management in the primary care setting in Germany. Medication reviews of 446 study participants were conducted by pharmacists based on a comprehensive baseline assessment that included a computer-based home medication assessment. ClinicalTrials.gov Identifier: NCT01401582. RESULTS: A total of 1,077 DRPs were documented. In 414 study participants (93%), at least one DRP was detected by a pharmacist. The most frequent DRPs were administration and compliance problems (60%), drug interactions (17%), and problems with inappropriate drug choice (15%). The number of DRPs was significantly associated with the total number of drugs taken and with a formal diagnosis of a mental or behavioral disorder. CONCLUSIONS: Degree of cognitive impairment (MMSE defined) and formal diagnosis of dementia were not risk factors for an increased number of DRPs. However, the total number of drug taken and the presence of a diagnosis of mental and behavioral disorders were associated with an increased total number of DRPs.


Assuntos
Disfunção Cognitiva/epidemiologia , Demência/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Feminino , Alemanha/epidemiologia , Humanos , Vida Independente , Modelos Logísticos , Masculino , Análise Multivariada , Atenção Primária à Saúde/organização & administração , Escalas de Graduação Psiquiátrica , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Phys Rev Lett ; 116(19): 197202, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27232040

RESUMO

We report ac susceptibility, specific heat, and neutron scattering measurements on a dipolar-coupled antiferromagnet LiYbF_{4}. For the thermal transition, the order-parameter critical exponent is found to be 0.20(1) and the specific-heat critical exponent -0.25(1). The exponents agree with the 2D XY/h_{4} universality class despite the lack of apparent two-dimensionality in the structure. The order-parameter exponent for the quantum phase transitions is found to be 0.35(1) corresponding to (2+1)D. These results are in line with those found for LiErF_{4} which has the same crystal structure, but largely different T_{N}, crystal field environment and hyperfine interactions. Our results therefore experimentally establish that the dimensional reduction is universal to quantum dipolar antiferromagnets on a distorted diamond lattice.

11.
Eur J Public Health ; 26(2): 339-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26498955

RESUMO

BACKGROUND: Studies on tobacco in the prison environment report high prevalence of use among detainees, but little data regarding staff are available. An observational study addressing tobacco control in German prisons was conducted in 2011. It involved multiple strands (quantitative and qualitative components) both among detainees and staff. This article presents quantitative results regarding staff. METHODS: Cross-sectional study among prison employees in 16 different institutions in nine regions (Länder) in Germany. Tobacco use and second-hand smoke (SHS) exposure (primary outcomes) were assessed by a questionnaire designed specifically. Logistic regression models were used to assess the risk factors associated with each outcome. RESULTS: Among 704 participants (60.6% male, mean age 43.9 years ± 9.33), 27.7% are smokers and 68% declared to be exposed to SHS. Independent factors associated with smoking were female gender [odds ratio (OR) 1.49,P= 0.026], an age below 45 years (OR 1.35,P= 0.08) and working in areas other than administration (ORP= 0.08). An age below 45 was associated with a higher degree of self-reported SHS exposure. The association between SHS and gender was different depending on occupational area with significantly more men exposed to SHS in administrative area and more women in health/social area (interaction between gender and occupational area,P= 0.02). CONCLUSION: Importance of SHS exposure among prison employees and confirm the need for a comprehensive tobacco control policy including support to smoking cessation and better enforcement of the smoke-free regulation, especially where staff contributes to SHS. Particular attention has to be given to female employees.


Assuntos
Prisões/estatística & dados numéricos , Fumar/epidemiologia , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Adulto , Fatores Etários , Estudos Transversais , Feminino , Alemanha/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Ocupações/estatística & dados numéricos , Fatores Sexuais
12.
J Dairy Sci ; 99(11): 9114-9125, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27592427

RESUMO

Implementation of specific management strategies on dairy farms is currently the most effective way to reduce the prevalence of Johne's disease (JD), an infectious chronic enteritis of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). However, dairy farmers often fail to implement recommended strategies. The objective of this study was to assess perceptions of farmers participating in a JD prevention and control program toward recommended practices, and explore factors that influence whether or not a farmer adopts risk-reducing measures for MAP transmission. Semi-structured interviews were conducted with 25 dairy farmers enrolled in a voluntary JD control program in Alberta, Canada. Principles of classical grounded theory were used for participant selection, interviewing, and data analysis. Additionally, demographic data and MAP infection status were collected and analyzed using quantitative questionnaires and the JD control program database. Farmers' perceptions were distinguished according to 2 main categories: first, their belief in the importance of JD, and second, their belief in recommended JD prevention and control strategies. Based on these categories, farmers were classified into 4 groups: proactivists, disillusionists, deniers, and unconcerned. The first 2 groups believed in the importance of JD, and proactivists and unconcerned believed in proposed JD prevention and control measures. Groups that regarded JD as important had better knowledge about best strategies to reduce MAP transmission and had more JD risk assessments conducted on their farm. Although not quantified, it also appeared that these groups had more JD prevention and control practices in place. However, often JD was not perceived as a problem in the herd and generally farmers did not regard JD control as a "hot topic" in communications with their herd veterinarian and other farmers. Recommendations regarding how to communicate with farmers and motivate various groups of farmers according to their specific perceptions were provided to optimize adoption of JD prevention and control measures and thereby increase success of voluntary JD control programs.


Assuntos
Indústria de Laticínios , Paratuberculose/microbiologia , Paratuberculose/prevenção & controle , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Fazendeiros , Fazendas , Mycobacterium avium subsp. paratuberculosis
13.
J Dairy Sci ; 99(3): 2157-2160, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26778309

RESUMO

Johne's disease (JD) control programs for dairy farms have the general objective of reducing both cow- and herd-level prevalence of Mycobacterium avium ssp. paratuberculosis (MAP). An important aspect of many programs is herd testing for MAP to determine the infection status of participating farms. However, it is uncertain whether MAP herd-level prevalence on farms voluntarily participating in a JD control program is different from that on nonparticipating farms. Therefore, the aim was to compare MAP infection status of participants and nonparticipants in the Alberta Johne's Disease Initiative (AJDI), a voluntary JD control program initiated in 2010 in Alberta, Canada. Between September 2012 and August 2013, environmental fecal samples were collected from 93 randomly selected farms not enrolled in the AJDI. Additionally, 81 farms that initially enrolled in the AJDI during the same time interval were also sampled. Samples were collected from 6 defined locations on each farm and cultured for MAP. Results were confirmed using conventional IS900 PCR and F 0285 quantitative PCR. Overall, 51% of participating and 51% of nonparticipating farms were identified as being MAP-infected. Furthermore, based on multivariable logistic regression, the number of MAP-positive samples was not associated with AJDI participation (taking herd size into account as a potentially modifying or confounding variable). In conclusion, there was no indication that voluntary participation in the AJDI was associated with herd-level MAP prevalence.


Assuntos
Doenças dos Bovinos/epidemiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/epidemiologia , Alberta/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Indústria de Laticínios , Fezes/microbiologia , Feminino , Modelos Logísticos , Prevalência , Manejo de Espécimes
14.
Prostate ; 75(16): 1934-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26356236

RESUMO

BACKGROUND: The first evaluation of pelvic extended lymph node dissection (pLND) in oligometastatic prostate cancer (PCa) detected by (68)Ga-PSMA PET/CT. METHODS: Retrospective analysis of 35 PCa patients underwent (68)Ga-PSMA PET/CT affected by biochemical recurrence (BCR) after curative treatment (n = 23) or before primary therapy of high-risk PCa (n = 12). We performed pLND associated with pathologic imaging in 17 men with nodal oligometastatic PCa. RESULTS: Indicative lesions for PCa in PET/CT were detected in 91.4% (32 of 35) of patients. Nodal, bone, visceral (pulmonary), and within the prostate suspected disease were detected in 72% (23 of 32), 16% (5 of 32), 6% (2 of 32), and 47% (15 of 32) of patients, respectively. Median serum PSA in patients with pathological radiotracer uptake in recurrent and high-risk PCa patients was 2.9 ng/ml (range 0.18-30) and 19.5 ng/ml (range 6-90), respectively. The median number of removed lymph nodes with pLND in recurrent and high-risk PCa was 10 (range 4-17) and 12 (range 8-29) per patient and the median number of positive lymph nodes was 1 (range 1-2) and 3 (2-3) per patient, respectively. In total, two false positive and one false-negative lymph node were found. Diagnostic accuracies per nodal lesion in total of 213 removed nodes: sensitivity, 94%; specificity, 99%; positive predictive value (PPV), 89%, and negative predictive value (NPV), 99.5%. After pLND, 53% (9 of 17) of patients received androgen deprivation therapy and/or radiation therapy and hormonal therapy, while 47% (8 of 17) of patients remained free of any post-surgery therapy. Follow-up PSA remained less than 0.2 ng/ml in 82% (14 of 17) of patients. After pLND, immediate BCR (PSA never measured less than 0.2 ng/ml) in 18% (3 of 17) of patients was recorded. CONCLUSIONS: This represents the first study of pLND in the setting of nodal oligometastatic PCa detected by (68)Ga-PSMA PET/CT. The use of (68)Ga-PSMA PET/CT could be to improve the accuracy for the detection of nodal micrometastases. These promising findings need validation in larger studies.


Assuntos
Excisão de Linfonodo , Metástase Linfática/patologia , Neoplasias da Próstata/cirurgia , Idoso , Humanos , Metástase Linfática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
J Antimicrob Chemother ; 70(3): 686-96, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25587993

RESUMO

OBJECTIVES: Treatment outcome of MDR-TB is critically dependent on the proper use of second-line drugs as per the result of in vitro drug susceptibility testing (DST). We aimed to establish a standardized DST procedure based on quantitative determination of drug resistance and compared the results with those of genotypes associated with drug resistance. METHODS: The protocol, based on MGIT 960 and the TB eXiST software, was evaluated in nine European reference laboratories. Resistance detection at a screening drug concentration was followed by determination of resistance levels and estimation of the resistance proportion. Mutations in 14 gene regions were investigated using established techniques. RESULTS: A total of 139 Mycobacterium tuberculosis isolates from patients with MDR-TB and resistance beyond MDR-TB were tested for 13 antituberculous drugs: isoniazid, rifampicin, rifabutin, ethambutol, pyrazinamide, streptomycin, para-aminosalicylic acid, ethionamide, amikacin, capreomycin, ofloxacin, moxifloxacin and linezolid. Concordance between phenotypic and genotypic resistance was >80%, except for ethambutol. Time to results was short (median 10 days). High-level resistance, which precludes the therapeutic use of an antituberculous drug, was observed in 49% of the isolates. The finding of a low or intermediate resistance level in 16% and 35% of the isolates, respectively, may help in designing an efficient personalized regimen for the treatment of MDR-TB patients. CONCLUSIONS: The automated DST procedure permits accurate and rapid quantitative resistance profiling of first- and second-line antituberculous drugs. Prospective validation is warranted to determine the impact on patient care.


Assuntos
Antituberculosos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Europa (Continente) , Técnicas de Genotipagem/métodos , Humanos , Testes de Sensibilidade Microbiana/normas , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação
16.
Clin Radiol ; 70(9): 989-98, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26139384

RESUMO

AIM: To assess intervendor agreement of cardiovascular magnetic resonance feature tracking (CMR-FT) and to study the impact of repeated measures on reproducibility. MATERIALS AND METHODS: Ten healthy volunteers underwent cine imaging in short-axis orientation at rest and with dobutamine stimulation (10 and 20 µg/kg/min). All images were analysed three times using two types of software (TomTec, Unterschleissheim, Germany and Circle, cvi(42), Calgary, Canada) to assess global left ventricular circumferential (Ecc) and radial (Err) strains and torsion. Differences in intra- and interobserver variability within and between software types were assessed based on single and averaged measurements (two and three repetitions with subsequent averaging of results, respectively) as determined by Bland-Altman analysis, intraclass correlation coefficients (ICC), and coefficient of variation (CoV). RESULTS: Myocardial strains and torsion significantly increased on dobutamine stimulation with both types of software (p<0.05). Resting Ecc and torsion as well as Ecc values during dobutamine stimulation were lower measured with Circle (p<0.05). Intra- and interobserver variability between software types was lowest for Ecc (ICC 0.81 [0.63-0.91], 0.87 [0.72-0.94] and CoV 12.47% and 14.3%, respectively) irrespective of the number of analysis repetitions. Err and torsion showed higher variability that markedly improved for torsion with repeated analyses and to a lesser extent for Err. On an intravendor level TomTec showed better reproducibility for Ecc and torsion and Circle for Err. CONCLUSIONS: CMR-FT strain and torsion measurements are subject to considerable intervendor variability, which can be reduced using three analysis repetitions. For both vendors, Ecc qualifies as the most robust parameter with the best agreement, albeit lower Ecc values obtained using Circle, and warrants further investigation of incremental clinical merit.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Software , Adulto , Cardiotônicos , Dobutamina , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
17.
J Dairy Sci ; 98(11): 7831-45, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342983

RESUMO

The Alberta Johne's Disease Initiative (AJDI) is a voluntary, management-based prevention and control program for Johne's disease (JD), a wasting disease in ruminants that causes substantial economic losses to the cattle industry. Despite extensive communication about the program's benefits and low cost to participating producers, approximately 35% of Alberta dairy farmers have not enrolled in the AJDI. Therefore, the objective was to identify differences between AJDI nonparticipants and participants that may influence enrollment. Standardized questionnaires were conducted in person on 163 farms not participating and 61 farms participating in the AJDI. Data collected included demographic characteristics, internal factors (e.g., attitudes and beliefs of the farmer toward JD and the AJDI), external factors (e.g., farmers' JD knowledge and on-farm goals and constraints), as well as farmers' use and influence of various information sources. Nonparticipants and participants differed in at least some aspects of all studied categories. Based on logistic regression, participating farms had larger herds, higher self-assessed knowledge of JD, better understanding of AJDI details before participation, and used their veterinarian more often to get information about new management practices and technologies when compared with nonparticipants. In contrast, nonparticipants indicated that time was a major on-farm constraint and that participation in the AJDI would take too much time. They also indicated that they preferred to wait and see how the program worked on other farms before they participated.


Assuntos
Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios/métodos , Paratuberculose/prevenção & controle , Alberta , Animais , Bovinos , Indústria de Laticínios/organização & administração , Fazendeiros , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , Médicos Veterinários , Programas Voluntários/estatística & dados numéricos
18.
J Clin Microbiol ; 52(3): 940-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24403306

RESUMO

The rapid accurate detection of drug resistance mutations in Mycobacterium tuberculosis is essential for optimizing the treatment of tuberculosis and limiting the emergence and spread of drug-resistant strains. The TB Resistance line probe assay from Autoimmun Diagnostika GmbH (AID) (Strassburg, Germany) was designed to detect the most prevalent mutations that confer resistance to isoniazid, rifampin, streptomycin, amikacin, capreomycin, fluoroquinolones, and ethambutol. This assay detected resistance mutations in clinical M. tuberculosis isolates from areas with low and high levels of endemicity (Switzerland, n=104; South Africa, n=52) and in selected Mycobacterium bovis BCG 1721 mutant strains (n=5) with 100% accuracy. Subsequently, the line probe assay was shown to be capable of rapid genetic assessment of drug resistance in MGIT broth cultures, the results of which were in 100% agreement with those of DNA sequencing and phenotypic drug susceptibility testing. Finally, the line probe assay was assessed for direct screening of smear-positive clinical specimens. Screening of 98 clinical specimens demonstrated that the test gave interpretable results for >95% of them. Antibiotic resistance mutations detected in the clinical samples were confirmed by DNA sequencing. We conclude that the AID TB Resistance line probe assay is an accurate tool for the rapid detection of resistance mutations in cultured isolates and in smear-positive clinical specimens.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Humanos , Testes de Sensibilidade Microbiana/métodos , Mutação , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium bovis/genética , Sensibilidade e Especificidade , África do Sul , Suíça
19.
Euro Surveill ; 19(11)2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24679721

RESUMO

The goal of the present study was to examine the transmission dynamics of multidrug-resistant tuberculosis (MDR-TB) in Switzerland. Between 2006 and 2012, a total of 49 MDR-TB cases were reported to the Swiss Federal Office of Public Health, 46 of which were of foreign origin. All 49 initial strains were evaluated by molecular epidemiologic methods at the Swiss National Reference Centre for Mycobacteria. In 43 strains, unique DNA fingerprint patterns were identified. Twelve strains were grouped into six clusters. Data from contact tracing suggest likely in-country transmission in four clusters, mostly among close contacts. In the remaining two clusters, no contact tracing data were available, but the identified genotypes were known to be prevalent in the countries of origin of the patients, suggesting the possibility that the infection was acquired there. While most MDR-TB cases are imported to Switzerland, at least four of the 49 MDR-TB cases were due to transmission within the country. The imported cases, however, did not lead to secondary cases outside the circles of close contacts. The results also indicate that prevention of MDR-TB transmission among immigrants may require closer monitoring.


Assuntos
Emigrantes e Imigrantes , Epidemiologia Molecular , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Adulto , Idoso , Antituberculosos/uso terapêutico , Análise por Conglomerados , Busca de Comunicante/estatística & dados numéricos , Impressões Digitais de DNA , DNA Bacteriano/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/classificação , Prevalência , Suíça/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/genética
20.
Nervenarzt ; 85(2): 176-88, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24343110

RESUMO

Progressive, atrophic, asymmetrically distributed flaccid paresis of arm and hand muscles represents a frequent symptom of neuromuscular diseases that can be attributed to injury of the arm nerves, the plexus or the cervical roots. A timely and exact diagnosis is mandatory; however, the broad spectrum of differential diagnoses often represents a diagnostic challenge. A large variety of neuromuscular disorders need to be considered, encompassing autoimmune mediated inflammatory neuropathic conditions, such as multifocal motor neuropathy, as well as chronic degenerative and nerve compression disorders. This review provides an overview of the most frequent disorders of the upper plexus and cervical roots and summarizes the characteristic clinical features as well as electrodiagnostic and laboratory test results. In addition the diagnostic value of magnetic resonance imaging and sonography is discussed.


Assuntos
Neuropatias do Plexo Braquial/classificação , Neuropatias do Plexo Braquial/diagnóstico , Técnicas de Diagnóstico Neurológico , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética/métodos , Ultrassonografia/métodos
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