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1.
Rev Sci Instrum ; 93(9): 093303, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182508

RESUMO

We describe a newly developed polytetrafluoroethylene/copper capacitor driven by a cryogenic piezoelectric slip-stick stage and demonstrate with the chosen layout cryogenic capacitance tuning of ≈60 pF at ≈10 pF background capacitance. Connected to a highly sensitive superconducting toroidal LC circuit, we demonstrate tuning of the resonant frequency between 345 and 685 kHz, at quality factors Q > 100 000. Connected to a cryogenic ultra low noise amplifier, a frequency tuning range between 520 and 710 kHz is reached, while quality factors Q > 86 000 are achieved. This new device can be used as a versatile image current detector in high-precision Penning-trap experiments or as an LC-circuit-based haloscope detector to search for the conversion of axion-like dark matter to radio-frequency photons. This new development increases the sensitive detection bandwidth of our axion haloscope by a factor of ≈1000.

2.
Nature ; 601(7891): 53-57, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34987217

RESUMO

The standard model of particle physics is both incredibly successful and glaringly incomplete. Among the questions left open is the striking imbalance of matter and antimatter in the observable universe1, which inspires experiments to compare the fundamental properties of matter/antimatter conjugates with high precision2-5. Our experiments deal with direct investigations of the fundamental properties of protons and antiprotons, performing spectroscopy in advanced cryogenic Penning trap systems6. For instance, we previously compared the proton/antiproton magnetic moments with 1.5 parts per billion fractional precision7,8, which improved upon previous best measurements9 by a factor of greater than 3,000. Here we report on a new comparison of the proton/antiproton charge-to-mass ratios with a fractional uncertainty of 16 parts per trillion. Our result is based on the combination of four independent long-term studies, recorded in a total time span of 1.5 years. We use different measurement methods and experimental set-ups incorporating different systematic effects. The final result, [Formula: see text], is consistent with the fundamental charge-parity-time reversal invariance, and improves the precision of our previous best measurement6 by a factor of 4.3. The measurement tests the standard model at an energy scale of 1.96 × 10-27 gigaelectronvolts (confidence level 0.68), and improves ten coefficients of the standard model extension10. Our cyclotron clock study also constrains hypothetical interactions mediating violations of the clock weak equivalence principle (WEPcc) for antimatter to less than 1.8 × 10-7, and enables the first differential test of the WEPcc using antiprotons11. From this interpretation we constrain the differential WEPcc-violating coefficient to less than 0.030.

3.
Nature ; 596(7873): 514-518, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34433946

RESUMO

Efficient cooling of trapped charged particles is essential to many fundamental physics experiments1,2, to high-precision metrology3,4 and to quantum technology5,6. Until now, sympathetic cooling has required close-range Coulomb interactions7,8, but there has been a sustained desire to bring laser-cooling techniques to particles in macroscopically separated traps5,9,10, extending quantum control techniques to previously inaccessible particles such as highly charged ions, molecular ions and antimatter. Here we demonstrate sympathetic cooling of a single proton using laser-cooled Be+ ions in spatially separated Penning traps. The traps are connected by a superconducting LC circuit that enables energy exchange over a distance of 9 cm. We also demonstrate the cooling of a resonant mode of a macroscopic LC circuit with laser-cooled ions and sympathetic cooling of an individually trapped proton, reaching temperatures far below the environmental temperature. Notably, as this technique uses only image-current interactions, it can be easily applied to an experiment with antiprotons1, facilitating improved precision in matter-antimatter comparisons11 and dark matter searches12,13.

4.
Rev Sci Instrum ; 92(6): 063903, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243590

RESUMO

We present a new autoclave that enables in situ characterization of hydrothermal fluids at high pressures and high temperatures at synchrotron x-ray radiation sources. The autoclave has been specifically designed to enable x-ray absorption spectroscopy in fluids with applications to mineral solubility and element speciation analysis in hydrothermal fluids in complex compositions. However, other applications, such as Raman spectroscopy, in high-pressure fluids are also possible with the autoclave. First experiments were run at pressures between 100 and 600 bars and at temperatures between 25 °C and 550 °C, and preliminary results on scheelite dissolution in fluids of different compositions show that the autoclave is well suited to study the behavior of ore-forming metals at P-T conditions relevant to the Earth's crust.

5.
Antimicrob Resist Infect Control ; 9(1): 65, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410673

RESUMO

BACKGROUND: Healthcare-associated infections are the most frequent adverse events in healthcare worldwide, with limited available evidence suggesting highest burden in resource-limited settings. Recent Ebola epidemics emphasize the disastrous impact that spread of infectious agents within healthcare facilities can have, accentuating the need for improvement of infection control practices. Hand hygiene (HH) measures are considered to be the most effective tool to prevent healthcare-associated infections. However, HH knowledge and compliance are low, especially in vulnerable settings such as Guinea. The aim of PASQUALE (Partnership to Improve Patient Safety and Quality of Care) was to assess knowledge and compliance with HH and improve HH by incorporating the WHO HH Strategy within the Faranah Regional Hospital (FRH), Guinea. METHODS: In a participatory approach, a team of FRH staff and leadership was invited to identify priorities of the hospital prior to the start of PASQUALE. The local hygiene committee was empowered to increase its activities and take ownership of the HH improvement strategy. A baseline assessment of knowledge, perception and compliance was performed months before the intervention. The main intervention consisted of local alcohol-based-hand-rub (ABHR) production, with final product efficacy testing, in conjunction with a training adapted to the needs identified in the baseline assessment. A follow-up assessment was conducted directly after the training. Effectiveness of the intervention was assessed via uncontrolled before-and-after comparison. RESULTS: Baseline knowledge score (13.0/25) showed a significant increase to 19.0/25 in follow-up. Baseline-Compliance was 23.7% and increased significantly to 71.5% in follow-up. Compliance rose significantly across all professional groups except for midwifes and in all indications for HH, with the largest in the indication "Before aseptic tasks". The increase in compliance was associated with the intervention and remained significant after adjusting for confounders. The local pharmacy successfully supplies the entire hospital. The local supply resulted in a ten-fold increase of monthly hospital disinfectant consumption. CONCLUSION: The WHO HH strategy is an adaptable and effective method to improve HH knowledge and compliance in a resource-limited setting. Local production is a feasible method for providing self-sufficient supply of ABHR to regional hospitals like the FRH. Participatory approaches like hygiene committee ownership builds confidence of sustainability.


Assuntos
Infecção Hospitalar/prevenção & controle , Higiene das Mãos/organização & administração , Recursos Humanos em Hospital/educação , Fidelidade a Diretrizes/estatística & dados numéricos , Guiné , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Guias de Prática Clínica como Assunto , Organização Mundial da Saúde
6.
Nature ; 575(7782): 310-314, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31723290

RESUMO

Astrophysical observations indicate that there is roughly five times more dark matter in the Universe than ordinary baryonic matter1, and an even larger amount of the Universe's energy content is attributed to dark energy2. However, the microscopic properties of these dark components remain unknown. Moreover, even ordinary matter-which accounts for five per cent of the energy density of the Universe-has yet to be understood, given that the standard model of particle physics lacks any consistent explanation for the predominance of matter over antimatter3. Here we present a direct search for interactions of antimatter with dark matter and place direct constraints on the interaction of ultralight axion-like particles (dark-matter candidates) with antiprotons. If antiprotons have a stronger coupling to these particles than protons do, such a matter-antimatter asymmetric coupling could provide a link between dark matter and the baryon asymmetry in the Universe. We analyse spin-flip resonance data in the frequency domain acquired with a single antiproton in a Penning trap4 to search for spin-precession effects from ultralight axions, which have a characteristic frequency governed by the mass of the underlying particle. Our analysis constrains the axion-antiproton interaction parameter to values greater than 0.1 to 0.6 gigaelectronvolts in the mass range from 2 × 10-23 to 4 × 10-17 electronvolts, improving the sensitivity by up to five orders of magnitude compared with astrophysical antiproton bounds. In addition, we derive limits on six combinations of previously unconstrained Lorentz- and CPT-violating terms of the non-minimal standard model extension5.

7.
Phys Rev Lett ; 122(4): 043201, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768304

RESUMO

We report on the first detailed study of motional heating in a cryogenic Penning trap using a single antiproton. Employing the continuous Stern-Gerlach effect we observe cyclotron quantum transition rates of 6(1) quanta/h and an electric-field noise spectral density below 7.5(3.4)×10^{-20} V^{2} m^{-2} Hz^{-1}, which corresponds to a scaled noise spectral density below 8.8(4.0)×10^{-12} V^{2} m^{-2}, results which are more than 2 orders of magnitude smaller than those reported by other ion-trap experiments.

8.
Nature ; 550(7676): 371-374, 2017 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-29052625

RESUMO

Precise comparisons of the fundamental properties of matter-antimatter conjugates provide sensitive tests of charge-parity-time (CPT) invariance, which is an important symmetry that rests on basic assumptions of the standard model of particle physics. Experiments on mesons, leptons and baryons have compared different properties of matter-antimatter conjugates with fractional uncertainties at the parts-per-billion level or better. One specific quantity, however, has so far only been known to a fractional uncertainty at the parts-per-million level: the magnetic moment of the antiproton, . The extraordinary difficulty in measuring with high precision is caused by its intrinsic smallness; for example, it is 660 times smaller than the magnetic moment of the positron. Here we report a high-precision measurement of in units of the nuclear magneton µN with a fractional precision of 1.5 parts per billion (68% confidence level). We use a two-particle spectroscopy method in an advanced cryogenic multi-Penning trap system. Our result = -2.7928473441(42)µN (where the number in parentheses represents the 68% confidence interval on the last digits of the value) improves the precision of the previous best measurement by a factor of approximately 350. The measured value is consistent with the proton magnetic moment, µp = 2.792847350(9)µN, and is in agreement with CPT invariance. Consequently, this measurement constrains the magnitude of certain CPT-violating effects to below 1.8 × 10-24 gigaelectronvolts, and a possible splitting of the proton-antiproton magnetic moments by CPT-odd dimension-five interactions to below 6 × 10-12 Bohr magnetons.

9.
Nat Commun ; 8: 14084, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28098156

RESUMO

Our current understanding of the Universe comes, among others, from particle physics and cosmology. In particle physics an almost perfect symmetry between matter and antimatter exists. On cosmological scales, however, a striking matter/antimatter imbalance is observed. This contradiction inspires comparisons of the fundamental properties of particles and antiparticles with high precision. Here we report on a measurement of the g-factor of the antiproton with a fractional precision of 0.8 parts per million at 95% confidence level. Our value /2=2.7928465(23) outperforms the previous best measurement by a factor of 6. The result is consistent with our proton g-factor measurement gp/2=2.792847350(9), and therefore agrees with the fundamental charge, parity, time (CPT) invariance of the Standard Model of particle physics. Additionally, our result improves coefficients of the standard model extension which discusses the sensitivity of experiments with respect to CPT violation by up to a factor of 20.

10.
Rev Sci Instrum ; 87(11): 113305, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910537

RESUMO

We developed highly sensitive image-current detection systems based on superconducting toroidal coils and ultra-low noise amplifiers for non-destructive measurements of the axial frequencies (550-800 kHz) of single antiprotons stored in a cryogenic multi-Penning-trap system. The unloaded superconducting tuned circuits show quality factors of up to 500 000, which corresponds to a factor of 10 improvement compared to our previously used solenoidal designs. Connected to ultra-low noise amplifiers and the trap system, signal-to-noise-ratios of 30 dB at quality factors of >20 000 are achieved. In addition, we have developed a superconducting switch which allows continuous tuning of the detector's quality factor and to sensitively tune the particle-detector interaction. This allowed us to improve frequency resolution at constant averaging time, which is crucial for single antiproton spin-transition spectroscopy experiments, as well as improved measurements of the proton-to-antiproton charge-to-mass ratio.

11.
Gesundheitswesen ; 77(1): e1-7, 2015 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-24493580

RESUMO

BACKGROUND AND OBJECTIVES: Decreasing staff numbers compounded by an increasing number of cases is regarded as main challenge in German hospital nursing. These input reductions accompanied by output extensions imply that hospital nursing services have had to achieve a continuous productivity growth in the recent years. Appropriately targeted productivity enhancements require approved and effective methods for productivity acquisition and measurement. However, there is a lack of suitable productivity measurement instruments for hospital nursing services. This deficit is addressed in the present study by the development of an integrated productivity model for hospital nursing services. Conceptually, qualitative as well as quantitative aspects of nursing services productivity are equally taken into consideration. METHODS: Based on systematic literature reviews different conceptual frameworks of service productivity and the current state of research in hospital nursing services productivity were analysed. On this basis nursing sensitive inputs, processes and outputs were identified and integrated into a productivity model. RESULTS: As an adequate framework for a hospital nursing services productivity model the conceptual approach by Grönroos/Ojasalo was identified. The basic structure of this model was adapted stepwise to our study purpose by integrating theoretical and empirical findings from the research fields of service productivity, nursing productivity as well as national and international nursing research. Special challenges existed concerning the identification of relevant influencing factors as well as the representation of nursing sensitive outputs. The final result is an integrated productivity model, which can be used as an adequate framework for further research in hospital nursing productivity. CONCLUSIONS: Research on hospital nursing services productivity is rare, especially in Germany. The conceptual framework developed in this study builds on established knowledge in service productivity research. The theoretical findings have been advanced and adapted to the context of German hospital nursing services. The presented productivity model represents a unique combination of services and nursing services research, which did not exist so far. By operationalisation of the model's components it can be used as the basis for further empirical -research.


Assuntos
Eficiência Organizacional , Modelos Organizacionais , Serviço Hospitalar de Enfermagem/organização & administração , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Avaliação de Processos em Cuidados de Saúde/métodos , Avaliação de Processos em Cuidados de Saúde/organização & administração , Alemanha , Carga de Trabalho
12.
Eye (Lond) ; 28(5): 562-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24556885

RESUMO

PURPOSE: To determine whether the ratio of optic disk diameter to disk-to-macula distance (DD/DM) in children with optic nerve hypoplasia (ONH) changes over time. PATIENTS AND METHODS: Fifteen subjects (29 eyes) enrolled in a prospective registry study on ONH had fundus photography performed under the age of 24 months and again at 60 months. Using the ratio of the DD/DM method, the relative size of the optic disk was assessed twice for each photo by one masked expert examiner to determine whether any change in relative disk size occurred over time. RESULTS: There was no change in relative optic disk size between initial and final fundus photographs. The average (± SD) age at the time of initial and final fundus photography was, respectively, 11.6 ± 5.2 months and 60.6 ± 1.3 months. Strong concordance was noted between the average DD/DM of the initial and the final photographs (ρ=0.939; 95% CI: 0.893, 0.981). There was negligible difference between the individual time point measurements (-0.011 ± 0.03) (95% LOA: -0.07, 0.04). CONCLUSION: There were no clinically significant changes in relative optic disk size over time in children with ONH; thus, DD/DM measurements need not be adjusted by age beyond 1 year in children with this disorder.


Assuntos
Macula Lutea/patologia , Atrofia Óptica/patologia , Disco Óptico/patologia , Fatores Etários , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Reprodutibilidade dos Testes
13.
Trop Med Int Health ; 18(3): 377-84, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23294376

RESUMO

OBJECTIVES: In 2010-2011, recent graduates (2008 or earlier) of the Masters in International Health (MIH) (as offered by over 30 universities and institutions collaborating in the tropEd network) were surveyed. We aimed to examine whether the competencies gained proved appropriate for alumni's current positions and to develop the programme according to alumni's needs. METHODS: An online questionnaire was sent to 327 alumni. One hundred and seventy-seven responded and 99 met the inclusion criteria. We calculated frequency distributions of the answers and performed a bivariate analysis of certain variables. RESULTS: Alumni feel confident in all areas covered by the MIH. Most competencies acquired are perceived as essential or very relevant to their current position. Many respondents (77%) changed jobs after graduation, mostly from curative care to public health. More African and Asian alumni work in their country of origin (66% and 63%, respectively) than alumni from other continents (42%). The respondents had mostly worked at a national or provincial level, but after graduating mostly worked at international or national level. Alumni said that the network's mobility and flexibility had important advantages and disadvantages. CONCLUSIONS: This is the first alumni survey of the MIH programme offered through the international network tropEd. The results suggest that competencies gained by graduates are relevant for their current careers. We recommend offering better guidance to students planning modules and to improve administration.


Assuntos
Educação de Pós-Graduação , Educação Profissional em Saúde Pública , Saúde Global , Adulto , Competência Clínica , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Área de Atuação Profissional , Avaliação de Programas e Projetos de Saúde , Clima Tropical
14.
Rev Sci Instrum ; 83(1): 013904, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22299967

RESUMO

Data on partitioning behavior of elements between different phases at in situ conditions are crucial for the understanding of element mobility especially for geochemical studies. Here, we present results of in situ partitioning of trace elements (Zr, Pd, and Ru) between silicate and iron melts, up to 50 GPa and 4200 K, using a modified laser heated diamond anvil cell (DAC). This new experimental set up allows simultaneous collection of x-ray fluorescence (XRF) and x-ray diffraction (XRD) data as a function of time using the high pressure beamline ID27 (ESRF, France). The technique enables the simultaneous detection of sample melting based to the appearance of diffuse scattering in the XRD pattern, characteristic of the structure factor of liquids, and measurements of elemental partitioning of the sample using XRF, before, during and after laser heating in the DAC. We were able to detect elements concentrations as low as a few ppm level (2-5 ppm) on standard solutions. In situ measurements are complimented by mapping of the chemical partitions of the trace elements after laser heating on the quenched samples to constrain the partitioning data. Our first results indicate a strong partitioning of Pd and Ru into the metallic phase, while Zr remains clearly incompatible with iron. This novel approach extends the pressure and temperature range of partitioning experiments derived from quenched samples from the large volume presses and could bring new insight to the early history of Earth.

15.
Neurology ; 75(10): 924-32, 2010 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-20820004

RESUMO

BACKGROUND: The threat of emerging infections and recognition of novel immune-mediated forms of encephalitis has raised the profile of this condition in recent years. Incidence is poorly defined and most cases have an unknown cause. There is currently much interest in identification of new microbial agents of encephalitis, but no work has investigated systematically reasons for lack of pathogen identification in studies. METHODS: We systematically reviewed published literature on incidence and etiology of encephalitis in non-outbreak settings and explored possible explanations for the large number of cases of unknown etiology. RESULTS: Annual incidence ranged from 0.07 to 12.6 cases per 100,000 population with an evident decrease over time (p = 0.01). The proportion of cases with unknown etiology was high across studies (>50% in 26 of 41 studies), with strong evidence of heterogeneity in study findings (p < 0.001). Our meta-regression identified study period, setting, and subsyndrome to be the main contributors to between-study variation, rather than methodologic factors such as study design, case definitions, sample types, and testing strategies. CONCLUSIONS: Our findings support the hypothesis that new and emerging infectious agents, or new forms of immune-mediated encephalitis, may be responsible for cases currently of unknown cause and encourage the ongoing global effort to identify these. Our review highlights research areas that might lead to a better understanding of the causes of encephalitis and ultimately reduce the morbidity and mortality associated with this devastating condition.


Assuntos
Surtos de Doenças , Encefalite/epidemiologia , Encefalite/etiologia , Humanos , Incidência
16.
Br J Ophthalmol ; 94(10): 1358-62, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20576785

RESUMO

BACKGROUND/AIMS: Children with optic nerve hypoplasia (ONH) have visual impairment and may have hypopituitarism and developmental delay. Children with ONH have also been reported to have abnormal sleep-wake cycles. We assessed the incidence and nature of sleep-wake abnormalities in children with ONH. METHODS: Rest-activity patterns were assessed in 23 children with ONH using actigraphy, which is a non-invasive method for continuously monitoring activity. The children also had formal assessment of pituitary function, visual acuity measurements, assessment of papillary responsiveness, MRI scans of the head and assessment of neurocognitive function. RESULTS: Sufficient actigraphy data were obtained on 19 of the children. Analysis of expressed rhythmicity revealed normal rest-activity patterns in 13 children (68%). Of the six children (32%) with abnormal rhythmicity, three had fragmented sleep, one had free-running rest-activity cycles and two were arrhythmic. Of the children with normal rhythmicity, the following were found: hypoplastic corpus callosum in 30%, growth hormone deficiency in 53%, hypothyroidism in 23%, adrenal insufficiency in 30%, diabetes insipidus in 0% and developmental delay in 15%. Of the children with abnormal rhythmicity, the following were found: hypoplastic corpus callosum in 66% (p>0.05), severe visual impairment in 100% (p=0.006), abnormal pupillary responsiveness in 85% (p=0.0084), cognitive impairment in 100% (p=0.04) and multiple hormonal deficiencies in 66% (p=0.03). CONCLUSIONS: Abnormal rest-activity rhythmicity patterns are present in 30% of children with ONH. The best predictors of abnormal rhythmicity are severe vision impairment, abnormal pupillary responsiveness, developmental delay and multiple hormonal deficiencies.


Assuntos
Ritmo Circadiano/fisiologia , Nervo Óptico/anormalidades , Pré-Escolar , Transtornos Cognitivos/etiologia , Deficiências do Desenvolvimento/etiologia , Humanos , Imageamento por Ressonância Magnética , Pupila/fisiologia , Descanso/fisiologia , Fatores de Risco , Transtornos do Sono-Vigília , Transtornos da Visão/etiologia
17.
Diabetes Obes Metab ; 12(5): 437-41, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20415692

RESUMO

AIM: Postprandial release of intact proinsulin (IP) is an independent marker for beta-cell dysfunction in patients with type 2 diabetes. This open-label, parallel-group, two-arm, pilot study compared the beta-cell protective effect of adding insulin glargine (GLA) vs. NPH insulin to ongoing metformin. MATERIAL AND METHODS: Overall, 28 insulin-naive type 2 diabetes subjects (mean +/- SD age, 61.5 +/- 6.7 years; diabetes duration, 9.8 +/- 6.5 years; HbA1c, 7.1 +/- 0.5%; BMI, 30.7 +/- 4.3 kg/m(2)) treated with metformin and sulfonylurea were randomized to add once-daily GLA or NPH at bedtime. At baseline and after 3 months, subjects received a standardized breakfast, lunch and dinner, with pre- and postprandial blood sampling to measure plasma IP, total insulin and blood glucose (BG). RESULTS: Insulin dose after 3 months was comparable in both groups (GLA vs. NPH: 23.6 +/- 13.4 vs. 23.3 +/- 12.7; p = NS ). Both treatments significantly reduced fasting BG levels (GLA: 158 +/- 19 to 121 +/- 23 mg/dl; NPH: 156 +/- 34 to 119 +/- 29 mg/dl; both p < 0.01 vs. baseline). Fasting and postprandial BG levels did not differ between groups. IP levels decreased in both groups (p < 0.05 at all timepoints). Although IP release after breakfast did not differ between treatments, GLA induced a greater reduction in IP release after lunch (p = 0.08) and dinner (p = 0.04). Total plasma insulin levels did not differ between groups. CONCLUSIONS: Adding basal insulin to metformin reduces postprandial beta-cell load. While GLA and NPH had comparable effects at breakfast, GLA reduces beta-cell stress more effectively at dinner, and with a trend at lunch, most probably because of its longer lasting pharmacodynamic profile.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina Isófana/administração & dosagem , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/análogos & derivados , Metformina/administração & dosagem , Esquema de Medicação , Quimioterapia Combinada , Jejum , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Hipoglicemiantes/farmacologia , Insulina/administração & dosagem , Insulina/farmacologia , Insulina Glargina , Insulina Isófana/farmacologia , Insulina de Ação Prolongada , Células Secretoras de Insulina/metabolismo , Masculino , Metformina/farmacologia , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Prandial
18.
Int Health ; 2(3): 228, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24037704

RESUMO

The Publisher regrets that an error occurred in the name of the 6th listed co-author for this paper. B. Matthias was listed in the original paper instead of M. Borchert; the correct listing can be seen above.

19.
Br J Ophthalmol ; 94(8): 1017-23, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19955198

RESUMO

AIMS: In optic nerve hypoplasia (ONH), the extent of functional loss of retinal ganglion cells cannot be determined by ophthalmoscopic examination. The prognostic value of visual electrodiagnostic tests in infants and toddlers with ONH was assessed by comparison with visual outcome. METHODS: 85 participants with ONH had electroretinogram (ERG) and visual-evoked potential (VEP) testing to flash and to pattern-reversal checks and ocular fundus photography prior to 36 months of age. These initial measures were compared with visual acuity outcomes at 5 years of age in the better-seeing eye. RESULTS: Visual outcomes ranged from normal to no light perception. Electrodiagnostic tests with prognostic value were: the amplitude of the flash VEP (Spearman's rank correlations, p<0.001), the threshold category of stimulus (flash or check size) that elicited a VEP (p<0.001) and the amplitude of the N95 component of the pattern ERG (PERG) to 4-degree checks (p<0.02). Optic nerve size and co-existing pallor were also significant correlates. Stepwise regression analysis composed a best prediction model from VEP threshold category, optic nerve size and optic disc pallor (R(2)=58%; p<0.001). CONCLUSIONS: Optic disc diameter, observation of disc pallor, VEP and PERG testing in infancy are useful for establishing the visual prognosis at 5 years of age in children with ONH. This is consistent with the notion that these parameters are related to the anatomic and functional preservation of retinal ganglion cells.


Assuntos
Nervo Óptico/anormalidades , Transtornos da Visão/etiologia , Fatores Etários , Pré-Escolar , Eletrorretinografia/métodos , Métodos Epidemiológicos , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Lactente , Masculino , Disco Óptico/patologia , Nervo Óptico/patologia , Prognóstico , Células Ganglionares da Retina/fisiologia , Processamento de Sinais Assistido por Computador , Transtornos da Visão/patologia , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologia
20.
Diabetes Obes Metab ; 11(5): 464-71, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19422402

RESUMO

AIM: Insulin treatment is considered to be the final option for patients with progressive type 2 diabetes. This study investigated, whether reconverting type 2 patients from insulin treatment to oral treatment using pioglitazone is possible without deterioration of blood glucose control. METHODS: The PioSwitch study was a prospective, open label, proof of concept study. Thiazolidinedione-naïve patients with residual beta-cell function were switched from an existing insulin therapy to treatment with pioglitazone and glimepiride for 6 months. Efficacy was assessed by laboratory parameters and scores for evaluation of metabolic control, beta-cell function, insulin resistance and cardiovascular risk. RESULTS: In total, 98 patients [66 men, 32 women, age (mean +/- s.d.): 59 +/- 9 years; disease duration: 5.6 +/- 3.6 years; Hemoglobin A1c (HbA1c): 6.9 +/- 0.8%; body mass index (BMI): 33.9 +/- 5.2 kg/m(2), initial daily insulin therapy dose: 0.36 +/- 0.3 U/kg body weight] out of 117 screened patients were treated. During the observation period, 23 patients were prematurely terminated because of an increase in HbA1c from baseline > 0.5% or other reasons. In 75 patients (76%), no deterioration of glucose metabolism occurred and additional improvements were seen in the majority of the observation parameters [baseline vs. endpoint; HbA1c: 6.79 +/- 0.74%/6.66 +/- 0.69% (p < 0.05), glucose: 6.4 +/- 1.5/5.2 +/- 1.4 mmol/l (p < 0.001), adiponectin: 7 +/- 3 mg/l/17 +/- 8 mg/l (p < 0.001), C-peptide: 987 +/- 493/1756 +/- 789 (p < 0.001), sensitivity index derived from the intravenous glucose tolerance test (SI(ivGTT)): 1.21 +/- 0.85/1.49 +/- 0.95 (p < 0.05), hsCRP: 3.3 +/- 2.4/2.6 +/- 2.4 mg/l (p < 0.01), macrophage chemo-attractant protein 1 (MCP1): 487 +/- 246/382 +/- 295 ng/l (p < 0.05)]. BMI increased from 33.8 +/- 5.1 to 34.4 +/- 5.3 kg/m(2) (p < 0.001). CONCLUSIONS: The switch from insulin therapy resulting in a moderately HbA1c level, to oral treatment with pioglitazone was successful in a majority of patients with sufficient residual beta-cell function. It allows a simple and less expensive therapy with a better cardiovascular risk marker profile.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Adulto , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Pioglitazona , Estudos Prospectivos , Compostos de Sulfonilureia , Tiazolidinedionas , Resultado do Tratamento
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