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1.
Neuropsychol Rehabil ; 32(7): 1324-1336, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33602057

RESUMO

Integrating animals into therapy is applied increasingly in patients in a minimally conscious state (MCS). This pilot study investigates the effect of animal presence on frontal brain activity in MCS patients compared to healthy subjects. O2HB, HHb and tHb of two MCS patients and two healthy adults was measured in frontal cortex using functional near-infrared spectroscopy during three sessions with a live animal and three sessions with a mechanical toy animal present. Each session had five phases: (1) baseline, (2) watching animal, (3) passive contact, (4) active contact, (5) neutral. Data were descriptively analysed. All participants showed the largest hemodynamic response during direct contact with the live or toy animal compared to "baseline" and "watching." During active contact, three of the four participants showed a stronger response when stroking the live compared to the toy animal. All participants showed an inverted signal with higher HHb than O2Hb concentrations while stroking the live or toy animal. Animal contact leads to a neurovascular reaction in both MCS patients and healthy subjects, indicating elevated neural activity in the frontal cortex. We conclude that while a toy animal can elicit attention processes, active contact to a living animal is combined with emotional processes.


Assuntos
Emoções , Estado Vegetativo Persistente , Animais , Encéfalo/diagnóstico por imagem , Humanos , Projetos Piloto
3.
Sci Rep ; 10(1): 20177, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214682

RESUMO

Sunflower pollen was reported to contain respiratory allergens responsible for occupational allergy and pollinosis. The present study describes the comprehensive characterization of a major sunflower allergen Hel a 6. Natural Hel a 6 was purified from sunflower pollen by anion exchange and gel filtration chromatography. Hel a 6 reacted with IgE-antibodies from 57% of 39 sunflower-sensitized patient sera suggesting it to be a major allergen. The patients were of Indian origin and suffering from pollinosis and allergic rhinitis. Hel a 6 exhibited allergenic activity by stimulating mediator release from basophils. Monomeric Hel a 6 displayed pectate lyase activity. The effect of various physicochemical parameters such as temperature, pH, and calcium ion on the functional activity of Hel a 6 revealed a stable nature of the protein. Hel a 6 was folded, and its melting curve showed reversible denaturation in which it refolded back to its native conformation from a denatured state. Hel a 6 displayed a high degree of sequence conservation with the pectate lyase allergens from related taxonomic families such as Amb a 1 (67%) and Art v 6 (57%). The IgE-cross reactivity was observed between Hel a 6 and its ragweed and mugwort homologs. The cross-reactivity was further substantiated by the mediator release when Hel a 6-sensitized effector cells were cross-stimulated with Art v 6 and Amb a 1. Several putative B cell epitopes were predicted and mapped on these 3 allergens. Two antigenic regions were found to be commonly shared by these 3 allergens, which could be crucial for cross-reactivity. In conclusion, Hel a 6 serves as a candidate molecule for diagnosis and immunotherapy for weed allergy.


Assuntos
Alérgenos/química , Alérgenos/imunologia , Helianthus/química , Hipersensibilidade/imunologia , Polissacarídeo-Liases/imunologia , Alérgenos/isolamento & purificação , Alérgenos/metabolismo , Ambrosia/imunologia , Dicroísmo Circular , Reações Cruzadas , Epitopos/imunologia , Fazendas , Helianthus/imunologia , Histamina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Soros Imunes , Espectrometria de Massas , Proteínas de Plantas/química , Proteínas de Plantas/imunologia , Proteínas de Plantas/isolamento & purificação , Pólen/enzimologia , Pólen/imunologia , Polissacarídeo-Liases/química , Polissacarídeo-Liases/isolamento & purificação , Polissacarídeo-Liases/metabolismo , Dobramento de Proteína , Testes Cutâneos , Temperatura
4.
Int Arch Allergy Immunol ; 177(2): 116-122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29940558

RESUMO

BACKGROUND: Enhancing the quality and yield of protein production in heterologous expression systems is an important issue for developing new biopharmaceuticals. It has been shown that the dynamics of protein folding is influenced by codon frequencies. As codon usage frequencies are species specific, this can affect heterologous protein expression. In this respect, "codon harmonization," that is, the usage of synonymous codons with usage frequencies in the host resembling the usage frequencies in the native organism, is a promising strategy. As recombinant proteins are important tools in the area of allergy research, we investigated in this study the influence of codon harmonization on the production of the major birch pollen allergen Bet v 1.0101. METHODS: To accomplish this task, parallel production of several batches of rBet v 1, BWT, together with a harmonized variant, BH, was applied. The expression yield of soluble and insoluble protein was assayed via densitometric analysis of -SDS-PAGEs for every batch. The quality of purified proteins was assessed with a variety of physicochemical methods including mass spectrometry, circular dichroism, dynamic light scattering, Fourier transform infrared spectroscopy, in vitro degradation, and 1-anilino-8-naphthalene sulfonate-binding assays. Patients' IgE reactivity was tested in enzyme-linked immunosorbent assays and rat basophil mediator release experiments. RESULTS: No significant differences in the ligand-binding capacity and secondary structure elements, as well as, in immunological assays could be found; however, the production yield was drastically increased for BH. CONCLUSION: We could show that codon harmonization is a powerful method to enhance protein yields in heterologous expression systems and should be considered especially for difficult-to-express proteins.


Assuntos
Antígenos de Plantas/genética , Betula/genética , Códon/genética , Hipersensibilidade/imunologia , Pólen/imunologia , Proteínas Recombinantes/genética , Animais , Sequência de Bases , Betula/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Pólen/genética , Ligação Proteica , Ratos , Alinhamento de Sequência
6.
Sci Rep ; 7(1): 6049, 2017 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-28729676

RESUMO

Feverfew (Parthenium hysterophorus), an invasive weed from the Asteraceae family, has been reported as allergen source. Despite its relevance, knowledge of allergens is restricted to a partial sequence of a hydroxyproline-rich glycoprotein. We aimed to obtain the entire sequence for recombinant production and characterize feverfew pollen using proteomics and immunological assays. Par h 1, a defensin-proline fusion allergen was obtained by cDNA cloning and recombinantly produced in E. coli. Using two complementary proteomic strategies, a total of 258 proteins were identified in feverfew pollen among those 47 proteins belonging to allergenic families. Feverfew sensitized patients' sera from India revealed IgE reactivity with a pectate lyase, PR-1 protein and thioredoxin in immonoblot. In ELISA, recombinant Par h 1 was recognized by 60 and 40% of Austrian and Indian sera, respectively. Inhibition assays demonstrated the presence of IgE cross-reactive Par h 1, pectate lyase, lipid-transfer protein, profilin and polcalcin in feverfew pollen. This study reveals significant data on the allergenic composition of feverfew pollen and makes recombinant Par h 1 available for cross-reactivity studies. Feverfew might become a global player in weed pollen allergy and inclusion of standardized extracts in routine allergy diagnosis is suggested in exposed populations.


Assuntos
Alérgenos/metabolismo , Pólen/metabolismo , Proteoma , Proteômica , Tanacetum parthenium/metabolismo , Alérgenos/genética , Alérgenos/imunologia , Sequência de Aminoácidos , Imunoglobulina E/imunologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Pólen/imunologia , Proteômica/métodos , Tanacetum parthenium/genética , Tanacetum parthenium/imunologia
7.
Stroke ; 46(10): 2741-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26272385

RESUMO

BACKGROUND AND PURPOSE: Specific coagulation assays for non-vitamin K antagonist oral anticoagulants (NOAC) are relatively slow and often lack availability. Although specific point-of-care tests (POCT) are currently not available, NOAC are known to affect established coagulation POCT. This study aimed at determining the diagnostic accuracy of the CoaguChek POCT to rule out relevant concentrations of rivaroxaban, apixaban, and dabigatran in real-life patients. METHODS: We consecutively enrolled 60 ischemic stroke patients newly started on NOAC treatment and obtained blood samples at 6 prespecified time points. Samples were tested using the CoaguChek POCT, laboratory-based coagulation assays (prothrombin time and activated partial thromboplastin time, anti-Xa test and Hemoclot), and liquid chromatography-tandem mass spectrometry for direct determination of NOAC concentrations. RESULTS: Three hundred fifty-six blood samples were collected. The CoaguChek POCT strongly correlated (r=0.82 P<0.001) with rivaroxaban concentrations but did not accurately detect dabigatran or apixaban. If used to estimate the presence of low rivaroxaban concentrations, POCT was superior to predictions based on normal prothrombin time and activated partial thromboplastin time values even if sensitive reagents were used. POCT-results≤1.0 predicted rivaroxaban concentrations<32 and <100 ng/mL with a specificity of 90% and 96%, respectively. CONCLUSIONS: If anti-Xa test is not available, we propose the use of the CoaguChek POCT to guide thrombolysis decisions after individual risk assessment in rivaroxaban-treated patients having acute ischemic stroke. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02371044.


Assuntos
Anticoagulantes/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Testes Imediatos , Acidente Vascular Cerebral/prevenção & controle , Administração Oral , Idoso , Anticoagulantes/sangue , Dabigatrana/sangue , Dabigatrana/uso terapêutico , Inibidores do Fator Xa/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pirazóis/sangue , Pirazóis/uso terapêutico , Piridonas/sangue , Piridonas/uso terapêutico , Rivaroxabana/sangue , Rivaroxabana/uso terapêutico
8.
PLoS One ; 10(5): e0120038, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25978036

RESUMO

BACKGROUND: Pollen released by allergenic members of the botanically unrelated families of Asteraceae and Cupressaceae represent potent elicitors of respiratory allergies in regions where these plants are present. As main allergen sources the Asteraceae species ragweed and mugwort, as well as the Cupressaceae species, cypress, mountain cedar, and Japanese cedar have been identified. The major allergens of all species belong to the pectate lyase enzyme family. Thus, we thought to investigate cross-reactivity pattern as well as sensitization capacities of pectate lyase pollen allergens in cohorts from distinct geographic regions. METHODS: The clinically relevant pectate lyase pollen allergens Amb a 1, Art v 6, Cup a 1, Jun a 1, and Cry j 1 were purified from aqueous pollen extracts, and patients' sensitization pattern of cohorts from Austria, Canada, Italy, and Japan were determined by IgE ELISA and cross-inhibition experiments. Moreover, we performed microarray experiments and established a mouse model of sensitization. RESULTS: In ELISA and ELISA inhibition experiments specific sensitization pattern were discovered for each geographic region, which reflected the natural allergen exposure of the patients. We found significant cross-reactivity within Asteraceae and Cupressaceae pectate lyase pollen allergens, which was however limited between the orders. Animal experiments showed that immunization with Asteraceae allergens mainly induced antibodies reactive within the order, the same was observed for the Cupressaceae allergens. Cross-reactivity between orders was minimal. Moreover, Amb a 1, Art v 6, and Cry j 1 showed in general higher immunogenicity. CONCLUSION: We could cluster pectate lyase allergens in four categories, Amb a 1, Art v 6, Cup a 1/Jun a 1, and Cry j 1, respectively, at which each category has the potential to sensitize predisposed individuals. The sensitization pattern of different cohorts correlated with pollen exposure, which should be considered for future allergy diagnosis and therapy.


Assuntos
Alérgenos/imunologia , Pólen/imunologia , Polissacarídeo-Liases/imunologia , Ambrosia/imunologia , Animais , Antígenos de Plantas/imunologia , Artemisia/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C
9.
Toxicol Rep ; 1: 843-857, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-28962296

RESUMO

During therapeutic interventions, blood concentrations of intravenously applied drugs are higher, and their onset of pharmacological action is faster than with other routes of drug administration. However, acute drug therapy often produces nephrotoxic side effects, as commonly seen after treatment with Ketorolac or Gentamicin leading to questions about their use, especially for patients at risk for acute renal failure. Omega-6(n-6) and omega-3(n-3) polyunsaturated fatty acids (PUFA) affect eicosanoid metabolism, which plays a role in the regulation of inflammation. Eicosanoids derived from n-6 FA have proinflammatory and immunoactive functions, whereas eicosanoids derived from n-3 PUFA have anti-inflammatory and cytoprotective properties. We hypothesized that providing such injectable drugs with nephrotoxic potential in combination with n3-PUFAs from the outset, might afford rapid cytoprotection of renal cells, given the recent evidence that intravenously administered n3-PUFAs are rapidly incorporated into cell membranes. We used intraglomerular mesangial cells (MES13) that are sensitive to treatment with Ketorolac or Gentamicin instead of proximal tubular cells which do not respond to Ketorolac. We found a significant inhibition of Ketorolac (0.25, 0.5, 1 mM) or Gentamicin (2.5, 5 mM) induced cytotoxicity after pretreatment of MES13 cells with 0.01% of 20%w/v LipOmega-3 Emulsion 9/1, containing 90:10 wt/wt mixture of fish oil derived triglycerides to medium chain triglycerides.

10.
Neuroimage ; 63(1): 212-22, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22732563

RESUMO

The present study aimed to step into two-person neuroscience by investigating the hemodynamic correlates of between-brain connectivity involved in imitation and its dependency on pacing stimuli. To test this approach, we used wireless functional near-infrared spectroscopy (fNIRS) to record simultaneously during imitation performance of a paced finger-tapping task (PFT) in two subjects over premotor cortices (PMC). During the imitation (IM) condition, a model and an imitator were recorded while tapping in synchrony with auditory stimuli separated by a constant interval (stimulus-paced mode, St-P), followed by tapping without the pacing stimulus (self-paced mode, Se-P). During the control (CO) condition, each subject (single 1 and 2) performed the PFT task with the same pacing mode pattern, but alone without reference to each other. Using wavelet transform coherence (WTC) analysis evaluating functional connectivity between brains, we found (1) that IM revealed a larger coherence increase between the model and the imitator as compared to the CO condition. (2) Within the IM condition, a larger coherence increase was found during Se-P as compared to St-P mode. Using Granger-causality (G-causality) analysis evaluating effective connectivity between brains, we found (3) that IM revealed larger G-causality as compared to the CO condition and (4) that within the IM condition, the signal of the model G-caused that of the imitator to a greater extent as compared to vice versa. Our findings designate fNIRS as suitable tool for monitoring between-brain connectivity during dynamic interactions between two subjects and that those measurements might thereby provide insight into activation patterns not detectable using typical single-person experiments. Overall, the results of the present study demonstrate the potential of simultaneously assessing brain hemodynamics in interacting subjects in several research areas where social interactions are involved.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Comportamento Imitativo/fisiologia , Movimento/fisiologia , Rede Nervosa/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise e Desempenho de Tarefas , Estimulação Acústica , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino
12.
Behav Brain Res ; 229(1): 29-40, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22227507

RESUMO

Trial-to-trial variability is a well-known issue in brain signals measured using functional near-infrared spectroscopy (fNIRS). We aimed to investigate whether trial-to-trial variability does provide information about individual performance. Seventeen subjects observed a virtual reality grasping task in first-person view while either imagining (motor imagery during observation, MIO) or imitating (motor execution, ME) the movements. Each condition was performed with the display in one of two positions, a conventional vertical position and a mirrored horizontal position which placed the virtual arm in the correct position relative to the viewpoint. Averaged oxy-hemoglobin concentration Δ[O(2)Hb] showed that the responses could be differentiated into two distinct groups: low responders (LR) and high responders (HR). Within groups, two main sources of trial-to-trial variability were identified: (a) the Δ[O(2)Hb] amplitude, with largest amplitudes in ME conditions (group HR) and smallest amplitudes in MIO conditions (group LR), and (b) the sign of Δ[O(2)Hb], with positive responses occurring most frequently during ME (group HR) and negative responses most frequently during MIO (group LR). Furthermore, the trial-to-trial dynamics differed between groups and could be described in group LR as inverted polynomial U-shaped curve in the mirror conditions (ME-mirror, MIO-mirror). Last, trial-to-trial variability was significantly dependent on task modality, i.e. ME (group HR) versus MIO (group LR), and/or the mirrored display positions (group LR). Our results show a relationship of trial-to-trial variability to individual MI performance, which may be of significance for neurorehabilitation applications. Although the sources of trial-to-trial variability remain unknown, we suggest that they may contribute to future neurofeedback applications.


Assuntos
Mapeamento Encefálico , Imagens, Psicoterapia , Córtex Motor/metabolismo , Movimento/fisiologia , Oxiemoglobinas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Análise de Variância , Análise Discriminante , Eletromiografia , Feminino , Lateralidade Funcional , Hemoglobinas/metabolismo , Humanos , Masculino , Observação , Adulto Jovem
13.
Cortex ; 48(5): 593-603, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21377666

RESUMO

Motor imagery (MI) is widely used to study cognitive action control. Although, the neural simulation theory assumes that MI and motor execution (ME) share many common features, the extent of similarity and whether it spreads into the preparation phase is still under investigation. Here we asked, whether an extension of physiological mental preparation has a comparable effect on MI and ME. Data were recorded using wireless functional near-infrared spectroscopy (fNIRS) in a two-stage task design where subjects were cued with or without preparatory stimuli to either execute or imagine complex sequential thumb-finger tasks. The main finding is that the extended mental preparation has a significant positive effect on oxy-hemoglobin (∆[O(2)Hb]) in response to MI, which is proportionally larger as that found in response to ME. Furthermore, fNIRS was capable to discriminate within each task whether it was preceded by preparatory stimuli or not. Transition from mental preparation to actual performance (ME or MI) was reflected by a dip of the fNIRS signal presumably related to underlying cortical processes changing between preparation and task performance. Statistically significant main effects of 'Preparation' and 'Task' showed that ∆[O(2)Hb] during preparation was preparation-specific, i.e., positively affected by the presence of preparatory stimuli, whereas during task performance ∆[O(2)Hb] was both preparation- and task-specific, i.e., additionally affected by the task mode. These results are particularly appealing from a practical point of view for making use of MI in neuroscientific applications. Especially neurorehabilitation and neural interfaces may benefit from utilizing positive interactions between mental preparation and MI performance.


Assuntos
Imaginação/fisiologia , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Pensamento/fisiologia , Adulto , Feminino , Humanos , Masculino , Movimento/fisiologia , Estimulação Luminosa , Espectroscopia de Luz Próxima ao Infravermelho
14.
J Neuroeng Rehabil ; 8: 34, 2011 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-21682906

RESUMO

BACKGROUND: For brain computer interfaces (BCIs), which may be valuable in neurorehabilitation, brain signals derived from mental activation can be monitored by non-invasive methods, such as functional near-infrared spectroscopy (fNIRS). Single-trial classification is important for this purpose and this was the aim of the presented study. In particular, we aimed to investigate a combined approach: 1) offline single-trial classification of brain signals derived from a novel wireless fNIRS instrument; 2) to use motor imagery (MI) as mental task thereby discriminating between MI signals in response to different tasks complexities, i.e. simple and complex MI tasks. METHODS: 12 subjects were asked to imagine either a simple finger-tapping task using their right thumb or a complex sequential finger-tapping task using all fingers of their right hand. fNIRS was recorded over secondary motor areas of the contralateral hemisphere. Using Fisher's linear discriminant analysis (FLDA) and cross validation, we selected for each subject a best-performing feature combination consisting of 1) one out of three channel, 2) an analysis time interval ranging from 5-15 s after stimulation onset and 3) up to four Δ[O2Hb] signal features (Δ[O2Hb] mean signal amplitudes, variance, skewness and kurtosis). RESULTS: The results of our single-trial classification showed that using the simple combination set of channels, time intervals and up to four Δ[O2Hb] signal features comprising Δ[O2Hb] mean signal amplitudes, variance, skewness and kurtosis, it was possible to discriminate single-trials of MI tasks differing in complexity, i.e. simple versus complex tasks (inter-task paired t-test p ≤ 0.001), over secondary motor areas with an average classification accuracy of 81%. CONCLUSIONS: Although the classification accuracies look promising they are nevertheless subject of considerable subject-to-subject variability. In the discussion we address each of these aspects, their limitations for future approaches in single-trial classification and their relevance for neurorehabilitation.


Assuntos
Encéfalo/fisiologia , Imaginação/fisiologia , Movimento/fisiologia , Reabilitação/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho , Interface Usuário-Computador , Adulto , Interpretação Estatística de Dados , Análise Discriminante , Eletromiografia , Feminino , Dedos/fisiologia , Lateralidade Funcional , Hemodinâmica/fisiologia , Hemoglobinas/metabolismo , Humanos , Cinestesia , Modelos Lineares , Masculino , Doenças do Sistema Nervoso/reabilitação , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes
15.
Eur J Neurosci ; 33(12): 2318-28, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21631608

RESUMO

Motor imagery (MI) is described as the mental rehearsal of voluntary movements. We used wireless functional near-infrared spectroscopy (fNIRS) recorded over secondary motor areas during performance of MI and motor execution (ME) in 11 healthy subjects, who either executed or imagined two drawing tasks differing in shape and frequency, i.e. simple (circle, 0.2 Hz) and complex (curved shape, 0.333 Hz). At the group level, results showed that fNIRS is capable of discriminating between the task mode, i.e. MI vs. ME, and the task complexity, i.e. simple vs. complex. At the single-subject level, we observed inverse oxygenation responses, i.e. a decrease in Δ[O(2) Hb] and/or increase in Δ[HHb]. These inverse responses only occurred during MI tasks and were highly correlated, in the first place, with task mode, and secondly with task complexity. Inverse Δ[O(2) Hb] responses are likely to reflect individual differences in performance-related signals and may contribute to the commonly observed inter-subject variability in fNIRS measurements. As MI is now widely used as a mental task in neurorehabilitative applications, the resulting oxygenation pattern may be of use for future developments. For this programme to be successful it is crucial to determine the sources of inter-subject variability. Our study presents a first effort in this direction, indicating that MI-related inverse Δ[O(2) Hb] responses are correlated, first, with task mode and, secondly, with task complexity.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Hemoglobinas/metabolismo , Imaginação/fisiologia , Atividade Motora/fisiologia , Oxiemoglobinas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto , Feminino , Humanos , Masculino , Córtex Motor/metabolismo , Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação
16.
Artigo em Inglês | MEDLINE | ID: mdl-19474239

RESUMO

Homeopathic preparations are used in homeopathy and anthroposophic medicine. Although there is evidence of effectiveness in several clinical studies, including double-blinded randomized controlled trials, their nature and mode of action could not be explained with current scientific approaches yet. Several physical methods have already been applied to investigate homeopathic preparations but it is yet unclear which methods are best suited to identify characteristic physicochemical properties of homeopathic preparations. The aim of this study was to investigate homeopathic preparations with UV-spectroscopy. In a blinded, randomized, controlled experiment homeopathic preparations of copper sulfate (CuSO(4); 11c-30c), quartz (SiO(2); 10c-30c, i.e., centesimal dilution steps) and sulfur (S; 11×-30×, i.e., decimal dilution steps) and controls (one-time succussed diluent) were investigated using UV-spectroscopy and tested for contamination by inductively coupled plasma mass spectrometry (ICP-MS). The UV transmission for homeopathic preparations of CuSO(4) preparations was significantly lower than in controls. The transmission seemed to be also lower for both SiO(2) and S, but not significant. The mean effect size (95% confidence interval) was similar for the homeopathic preparations: CuSO(4) (pooled data) 0.0544% (0.0260-0.0827%), SiO(2) 0.0323% (-0.0064% to 0.0710%) and S 0.0281% (-0.0520% to 0.1082%). UV transmission values of homeopathic preparations had a significantly higher variability compared to controls. In none of the samples the concentration of any element analyzed by ICP-MS exceeded 100 ppb. Lower transmission of UV light may indicate that homeopathic preparations are less structured or more dynamic than their succussed pure solvent.

17.
J Neuroeng Rehabil ; 7: 57, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21122154

RESUMO

BACKGROUND: Several neurorehabilitation strategies have been introduced over the last decade based on the so-called simulation hypothesis. This hypothesis states that a neural network located in primary and secondary motor areas is activated not only during overt motor execution, but also during observation or imagery of the same motor action. Based on this hypothesis, we investigated the combination of a virtual reality (VR) based neurorehabilitation system together with a wireless functional near infrared spectroscopy (fNIRS) instrument. This combination is particularly appealing from a rehabilitation perspective as it may allow minimally constrained monitoring during neurorehabilitative training. METHODS: fNIRS was applied over F3 of healthy subjects during task performance in a virtual reality (VR) environment: 1) 'unilateral' group (N = 15), contralateral recording during observation, motor imagery, observation & motor imagery, and imitation of a grasping task performed by a virtual limb (first-person perspective view) using the right hand; 2) 'bilateral' group (N = 8), bilateral recording during observation and imitation of the same task using the right and left hand alternately. RESULTS: In the unilateral group, significant within-condition oxy-hemoglobin concentration Δ[O2Hb] changes (mean ± SD µmol/l) were found for motor imagery (0.0868 ± 0.5201 µmol/l) and imitation (0.1715 ± 0.4567 µmol/l). In addition, the bilateral group showed a significant within-condition Δ[O2Hb] change for observation (0.0924 ± 0.3369 µmol/l) as well as between-conditions with lower Δ[O2Hb] amplitudes during observation compared to imitation, especially in the ipsilateral hemisphere (p < 0.001). Further, in the bilateral group, imitation using the non-dominant (left) hand resulted in larger Δ[O2Hb] changes in both the ipsi- and contralateral hemispheres as compared to using the dominant (right) hand. CONCLUSIONS: This study shows that our combined VR-fNIRS based neurorehabilitation system can activate the action-observation system as described by the simulation hypothesis during performance of observation, motor imagery and imitation of hand actions elicited by a VR environment. Further, in accordance with previous studies, the findings of this study revealed that both inter-subject variability and handedness need to be taken into account when recording in untrained subjects. These findings are of relevance for demonstrating the potential of the VR-fNIRS instrument in neurofeedback applications.


Assuntos
Imagens, Psicoterapia/métodos , Comportamento Imitativo/fisiologia , Transtornos dos Movimentos/fisiopatologia , Transtornos dos Movimentos/reabilitação , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Interface Usuário-Computador , Tecnologia sem Fio/instrumentação , Adulto , Feminino , Humanos , Masculino , Movimento/fisiologia , Transtornos dos Movimentos/diagnóstico , Desempenho Psicomotor/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Adulto Jovem
18.
ScientificWorldJournal ; 10: 49-61, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-20062950

RESUMO

Clinical trials have reported statistically significant and clinically relevant effects of homeopathic preparations. We applied ultraviolet (UV) spectroscopy to investigate the physical properties of homeopathic preparations and to contribute to an understanding of the not-yet-identified mode of action. In previous investigations, homeopathic preparations had significantly lower UV light transmissions than controls. The aim of this study was to explore the possible effects of external factors (UV light and temperature) on the homeopathic preparations. Homeopathic centesimal (c) dilutions, 1c to 30c, of copper sulfate (CuSO(4)), decimal dilutions of sulfur (S(8)), 1x to 30x, and controls (succussed potentization medium) were prepared, randomized, and blinded. UV transmission was measured at six different time points after preparation (from 4 to 256 days). In addition, one series of samples was exposed to UV light of a sterilization lamp for 12 h, one was incubated at 37 degrees Celsius for 24 h, and one was heated to 90 degrees Celsius for 15 min. UV light transmission values from 190 or 220 nm to 340 nm were measured several times and averaged. After each exposure, UV transmission of the homeopathic preparations of CuSO(4) was significantly reduced compared to the controls, particularly after heating to 37 degrees Celsius. Overall, the nonexposed CuSO(4) preparations did not show significantly lower UV transmission compared to controls; however, the pooled subgroup of measurements at days 26, 33, and 110 yielded significant differences. UV light transmission for S(8) preparations did not show any differences compared to controls. Our conclusion is that exposure to external factors, incubation at 37 degrees Celsius in particular, increases the difference in light transmission of homeopathic CuSO(4) preparations compared to controls.


Assuntos
Sulfato de Cobre/química , Espectrofotometria Ultravioleta/métodos , Enxofre/química , Homeopatia/métodos , Temperatura Alta , Fotoquímica , Temperatura , Fatores de Tempo , Raios Ultravioleta
19.
Naturwissenschaften ; 96(9): 1079-89, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19533076

RESUMO

Quantitative meta-analyses of randomized clinical trials investigating the specific therapeutic efficacy of homeopathic remedies yielded statistically significant differences compared to placebo. Since the remedies used contained mostly only very low concentrations of pharmacologically active compounds, these effects cannot be accounted for within the framework of current pharmacology. Theories to explain clinical effects of homeopathic remedies are partially based upon changes in diluent structure. To investigate the latter, we measured for the first time high-field (600/500 MHz) 1HT(1) and T(2) nuclear magnetic resonance relaxation times of H2O in homeopathic preparations with concurrent contamination control by inductively coupled plasma mass spectrometry (ICP-MS). Homeopathic preparations of quartz (10c-30c, n = 21, corresponding to iterative dilutions of 100(-10)-100(-30)), sulfur (13x-30x, n = 18, 10(-13)-10(-30)), and copper sulfate (11c-30c, n = 20, 100(-11)-100(-30)) were compared to n = 10 independent controls each (analogously agitated dilution medium) in randomized and blinded experiments. In none of the samples, the concentration of any element analyzed by ICP-MS exceeded 10 ppb. In the first measurement series (600 MHz), there was a significant increase in T(1) for all samples as a function of time, and there were no significant differences between homeopathic potencies and controls. In the second measurement series (500 MHz) 1 year after preparation, we observed statistically significant increased T(1) relaxation times for homeopathic sulfur preparations compared to controls. Fifteen out of 18 correlations between sample triplicates were higher for controls than for homeopathic preparations. No conclusive explanation for these phenomena can be given at present. Possible hypotheses involve differential leaching from the measurement vessel walls or a change in water molecule dynamics, i.e., in rotational correlation time and/or diffusion. Homeopathic preparations thus may exhibit specific physicochemical properties that need to be determined in detail in future investigations.


Assuntos
Sulfato de Cobre/análise , Materia Medica/análise , Quartzo/análise , Enxofre/análise , Estabilidade de Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas , Sensibilidade e Especificidade , Água/análise
20.
Forsch Komplementmed ; 13 Suppl 2: 4-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16883075

RESUMO

OBJECTIVE: Within the framework of the Swiss governmental Program of Evaluation of Complementary Medicine (PEK) we assessed the prevalence, use, perceived effectiveness and appreciation of complementary medicine (CAM) in Switzerland, according to published surveys. MATERIALS AND METHODS: Search was performed through electronic databases, by hand-searching and by contacting experts at universities, hospitals, health insurances, patient organizations and pharmaceutical companies. RESULTS: Surveys were carried out among the general population (40%), physicians (20%), hospitalized patients (30%) and obstetric institutions (5%). The number of publications increased strongly between 1981 and 2004. The mean +/- SD prevalence (use) of CAM is 49 +/- 22% and varies depending on the survey's topic and the population group interviewed. The acceptance, appreciation or demand for CAM among individuals specifically interviewed on CAM is 91 +/- 6%. When asked about favored general improvements in healthcare, 6.5% of the individuals spontaneously mentioned CAM. CAM therapies are considered to be effective by the majority of CAM users and by about 40% of cancer patients using CAM. Approximately 50% of the population stated a preference for hospitals that also provide CAM. 85% of the population wishes the costs for CAM to be covered by the basic health insurance. CONCLUSION: Approximately half of the Swiss population has used CAM. CAM treatment is considered to be effective by the majority of CAM users. About 50% of the population would prefer hospitals that also provide CAM therapies and the majority of the population wishes the cost for CAM therapies to be covered by basic health insurance.


Assuntos
Terapias Complementares/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Transversais , Pesquisas sobre Atenção à Saúde , Humanos , Suíça
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