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1.
Nature ; 606(7915): 678-682, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35732764

RESUMO

A long-standing question in nuclear physics is whether chargeless nuclear systems can exist. To our knowledge, only neutron stars represent near-pure neutron systems, where neutrons are squeezed together by the gravitational force to very high densities. The experimental search for isolated multi-neutron systems has been an ongoing quest for several decades1, with a particular focus on the four-neutron system called the tetraneutron, resulting in only a few indications of its existence so far2-4, leaving the tetraneutron an elusive nuclear system for six decades. Here we report on the observation of a resonance-like structure near threshold in the four-neutron system that is consistent with a quasi-bound tetraneutron state existing for a very short time. The measured energy and width of this state provide a key benchmark for our understanding of the nuclear force. The use of an experimental approach based on a knockout reaction at large momentum transfer with a radioactive high-energy 8He beam was key.

2.
J Intellect Disabil Res ; 68(6): 620-638, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38504557

RESUMO

BACKGROUND: Sleep-wake problems and depressive symptoms are common in people with intellectual disabilities (IDs) and are thought to be related to the unstable sleep-wake rhythm in this population. Previously, we showed that after increasing environmental light exposure, mid-sleep and sleep onset advanced, and mood improved over a period of 14 weeks after installing environmental dynamic light installations in the living room of people with IDs. We invited participants of that short-term study to take part in the current study on sleep-wake rhythm, mood and behaviour in older adults with IDs 1 year after installing environmental dynamic light installations in the common living rooms of six group homes. METHODS: A pre-post study was performed from October 2017 to February 2019. We included 45 participants (63.5 ± 8.5 years, 67% female) from six group home facilities who provided data at baseline (9, 4 and 1 weeks prior to installing light installations), short term (3, 7 and 14 weeks after installing light installations) and 1 year (54 weeks after installing light installations). Wrist activity was measured with actigraphy (GENEActiv) to derive the primary outcome of interdaily stability of sleep-wake rhythms as well as sleep estimates. Mood was measured with the Anxiety, Depression and Mood Scale. Behaviour was measured with the Aberrant Behaviour Checklist. RESULTS: One year after installing dynamic lighting, we did not find a change in interdaily stability. Total sleep time decreased (ß = -25.40 min; confidence interval: -10.99, -39.82), and sleep onset time was delayed (ß = 25.63 min; confidence interval: 11.18, 40.08). No effect on mood or behaviour was found. CONCLUSIONS: We did not find a change in sleep-wake rhythm, mood or behaviour in older persons with IDs living in care facilities 1 year after installing the light. We did find evidence for a long-term effect on sleep duration and sleep timing. The results have to be interpreted with care as the current study had a limited number of participants. The need for more research on the long-term effects of enhancing environmental light in ID settings is evident.


Assuntos
Afeto , Deficiência Intelectual , Iluminação , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Deficiência Intelectual/fisiopatologia , Idoso , Afeto/fisiologia , Actigrafia , Ritmo Circadiano/fisiologia , Lares para Grupos , Sono/fisiologia
3.
J Intellect Disabil Res ; 68(12): 1344-1357, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39148342

RESUMO

BACKGROUND: Older adults with intellectual disabilities (ID) have a high risk of cardiovascular diseases (CVD). At the same time, challenging diagnostic work-up increases the likelihood of underdiagnosis of CVD in this population. To limit this underdiagnosis, it would be beneficial to use objective measures such as the electrocardiogram (ECG). However, little is known about the feasibility of ECG recording and the prevalence of ECG abnormalities in this population. Therefore, the aims of this study were to investigate the feasibility of resting ECG recording, to study the prevalence of ECG abnormalities, and to compare the frequency of ECG abnormalities with medical records in older adults with ID. METHOD: A cross-sectional study was performed within a cohort of older adults (≥60 years) with ID as part of the Healthy Ageing and Intellectual Disabilities (HA-ID) study. A resting 12-lead ECG was attempted, and the ECG recording was considered feasible if the recording could be made and if the ECG could be interpreted by a cardiologist and the Modular ECG Analysis System (MEANS). ECGs were assessed for the presence of ECG abnormalities and medical record review was performed. If the cardiologist or MEANS concluded that there was evidence of myocardial infarction, atrial fibrillation or QTc prolongation on the ECG in the absence of this ECG diagnosis in the participant's medical record, this was classified as a previously undiagnosed ECG diagnosis. RESULTS: ECG recording was feasible in 134 of the 200 participants (67.0%). Of these 134 participants (70.6 ± 5.8 years; 52.2% female), 103 (76.9%) had one or more ECG abnormality, with the most prevalent being prolonged P-wave duration (27.6%), QTc prolongation (18.7%), minor T-wave abnormalities (17.9%), first degree atrioventricular block (12.7%) and myocardial infarction (6.7%). Eight out of 9 (88.9%) myocardial infarctions and all cases of (significant) QTc prolongation (100%) were previously undiagnosed. CONCLUSIONS: This study showed that ECG recording is feasible in the majority of older adults with ID and revealed a substantial underdiagnosis of ECG abnormalities. These results stress the importance of ECG recording and warrant further research into the yield of opportunistic ECG screening in older adults with ID.


Assuntos
Eletrocardiografia , Estudos de Viabilidade , Deficiência Intelectual , Humanos , Deficiência Intelectual/fisiopatologia , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/epidemiologia , Feminino , Masculino , Eletrocardiografia/métodos , Idoso , Pessoa de Meia-Idade , Estudos Transversais , Idoso de 80 Anos ou mais , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia
4.
Arch Womens Ment Health ; 26(6): 851-855, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37594562

RESUMO

Patients with Attention Deficit Hyperactivity Disorder (ADHD) are at greater cardiovascular risk. We investigated the association between ADHD symptoms and cardiovascular disease in women at a specialized Dutch cardiological clinic. Lifetime ADHD symptoms were found in 35% of women (n = 300) with cardiac complaints. Women with ADHD symptoms compared to those without were significantly younger but had no different cardiological profile. To protect women's health, further research and multidisciplinary cooperation is required to better understand the relationship between ADHD and cardiovascular disease.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Doenças Cardiovasculares , Humanos , Feminino , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Estudos Transversais , Doenças Cardiovasculares/epidemiologia , Saúde da Mulher
5.
J Intellect Disabil Res ; 66(10): 756-781, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36004439

RESUMO

BACKGROUND: Evidence-based interventions to improve the sleep-wake rhythm, mood and behaviour in older adults with intellectual disabilities (ID) are limited. Increasing light exposure has been shown to be effective in improving the sleep-wake rhythm, mood, and behaviour in other populations. The current study investigates the effect of installing environmental dynamic lighting in common living rooms of care facilities on sleep-wake rhythm, mood, and behaviour in older adults with ID. METHODS: A non-randomised, non-concurrent, multiple baseline study was performed from October 2017 to May 2018. Fifty-four participants [mean (SD) age of 63.42 (8.6) years, 65% female] in six care facilities were included. All participants had three baseline measurements (Weeks 1, 5 and 9). Dynamic lighting was installed in Week 10, after which three intervention measurements took place (Weeks 12, 17 and 24). Sleep characteristics and the sleep-wake rhythm were assessed using actigraphy (GENEActiv). Mood was measured with the Anxiety, Depression and Mood Scale (ADAMS) and behaviour with the Aberrant Behaviour Checklist (ABC). RESULTS: Mixed-effect regression analysis showed a worsening of the primary outcome interdaily stability (P = 0.001). This could be attributed to one care facility, whereas interdaily stability did not change in the other care facilities (P = 0.74). Dynamic lighting led to earlier mid-sleep (P = 0.003) and sleep onset (P < .0001) and improved mood as indicated by lower scores on the ADAMS depression (-0.64 SD, P < 0.001) and social avoidance (-0.47 SD, P = 0.004) subscales. The prevalence of screening above cut-off for depression decreased from 23 to 9.8% (OR = .16, P = 0.003). For behaviour, a decrease was seen in hyperactivity (-0.43 SD, P < 0.001), lethargy (-0.35 SD, P = 0.008) and irritability (-0.33 SD, P < .001) as measured with the ABC. No adverse effects were reported. CONCLUSION: Installing dynamic lighting in common living areas for older adults with ID improved the mood and behaviour of the residents up to 14 weeks after placement. Integrated dynamic lighting is a promising, undemanding and potentially effective addition to improve mood and behaviour in care organisations for people with ID, but does not seem to do so by improving sleep or sleep-wake rhythms.


Assuntos
Deficiência Intelectual , Iluminação , Actigrafia , Afeto , Idoso , Ritmo Circadiano , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sono
6.
Epidemiol Infect ; 149: e65, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33650470

RESUMO

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) led to a significant disease burden and disruptions in health systems. We describe the epidemiology and transmission characteristics of early coronavirus disease 2019 (COVID-19) cases in Bavaria, Germany. Cases were reverse transcription polymerase chain reaction (RT-PCR)-confirmed SARS-CoV-2 infections, reported from 20 January-19 March 2020. The incubation period was estimated using travel history and date of symptom onset. To estimate the serial interval, we identified pairs of index and secondary cases. By 19 March, 3546 cases were reported. A large proportion was exposed abroad (38%), causing further local transmission. Median incubation period of 256 cases with exposure abroad was 3.8 days (95%CI: 3.5-4.2). For 95% of infected individuals, symptom onset occurred within 10.3 days (95%CI: 9.1-11.8) after exposure. The median serial interval, using 53 pairs, was 3.5 days (95%CI: 3.0-4.2; mean: 3.9, s.d.: 2.2). Travellers returning to Germany had an important influence on the spread of SARS-CoV-2 infections in Bavaria in early 2020. Especially in times of low incidence, public health agencies should identify holiday destinations, and areas with ongoing local transmission, to monitor potential importation of SARS-CoV-2 infections. Travellers returning from areas with ongoing community transmission should be advised to quarantine to prevent re-introductions of COVID-19.


Assuntos
COVID-19/epidemiologia , COVID-19/transmissão , Alemanha , Humanos , Saúde Pública , Quarentena/estatística & dados numéricos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , Viagem/estatística & dados numéricos
7.
J Intellect Disabil Res ; 65(4): 361-372, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33594722

RESUMO

BACKGROUND: Light exposure affects mood and sleep regulation. Sleep problems and mood complaints are common in elderly with intellectual disabilities (ID) living in care facilities. Insufficient light exposure is hypothesised to contribute to the high prevalence of these problems. The current study is the first to describe the personal light exposure pattern during the waking day in elderly with ID. METHODS: The study sample consists of 82 elderly with ID (aged 62.3 ± 9.4 years) living in 16 residential homes of three care organisations in the Netherlands. Personal light exposure was measured continuously for 7-10 days using a HOBO data logger light sensor, measuring illuminance at chest height. Participants wore a wrist-worn accelerometer (Actiwatch or Geneactiv) to indicate the bedtimes to determine the waking day. RESULTS: The variation in illuminance is small during the waking day. Elderly with ID spend most of their waking day (mean duration = 14:32:43 h) in dim light (1-500 lux) environment and spend a median of 32 min in light > 1000 lux. Within participants, the threshold associated with better sleep (>50 min of light > 1000 lux) was reached for 34% of the days, and the threshold associated with less depressive symptoms (>30 min of light > 1000 lux) was reached in 46% of the days. Exposure > 1000 lux was lower during weekends than during weekdays. CONCLUSION: Elderly with ID spend most of their waking day in low light levels and did not meet the proposed values associated with better sleep and mood. Given the importance of adequate light exposure for regulation of sleep and mood, and the prevalence of sleep and mood problems in elderly with ID, the current study suggests that the lit environment for this already frail population should be given more attention.


Assuntos
Deficiência Intelectual , Afeto , Idoso , Ritmo Circadiano , Humanos , Deficiência Intelectual/epidemiologia , Países Baixos/epidemiologia , Prevalência , Sono
8.
Phys Rev Lett ; 125(26): 262301, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449792

RESUMO

Flow coefficients v_{n} of the orders n=1-6 are measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI for protons, deuterons, and tritons as a function of centrality, transverse momentum, and rapidity in Au+Au collisions at sqrt[s_{NN}]=2.4 GeV. Combining the information from the flow coefficients of all orders allows us to construct for the first time, at collision energies of a few GeV, a multidifferential picture of the angular emission pattern of these particles. It reflects the complicated interplay between the effect of the central fireball pressure on the emission of particles and their subsequent interaction with spectator matter. The high precision information on higher order flow coefficients is a major step forward in constraining the equation of state of dense baryonic matter.

9.
Phys Rev Lett ; 123(2): 022002, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386541

RESUMO

We present the first observation of K^{-} and ϕ absorption within nuclear matter by means of π^{-}-induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES at SIS18/GSI. The double ratio (K^{-}/K^{+})_{W}/(K^{-}/K^{+})_{C} is found to be 0.319±0.009(stat)_{-0.012}^{+0.014}(syst) indicating a larger absorption of K^{-} in heavier targets as compared to lighter ones. The measured ϕ/K^{-} ratios in π^{-}+C and π^{-}+W reactions within the HADES acceptance are found to be equal to 0.55±0.04(stat)_{-0.07}^{+0.06}(syst) and to 0.63±0.06(stat)_{-0.11}^{+0.11}(syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the ϕ meson in nuclear medium is strongly coupled to the K^{-} dynamics. The large difference in the ϕ production off C and W nuclei is discussed in terms of a strong ϕN in-medium coupling. These results are relevant for the description of heavy-ion collisions and the structure of neutron stars.

10.
Nature ; 486(7403): 341-5, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22722192

RESUMO

The shell structure of atomic nuclei is associated with 'magic numbers' and originates in the nearly independent motion of neutrons and protons in a mean potential generated by all nucleons. During ß(+)-decay, a proton transforms into a neutron in a previously not fully occupied orbital, emitting a positron-neutrino pair with either parallel or antiparallel spins, in a Gamow-Teller or Fermi transition, respectively. The transition probability, or strength, of a Gamow-Teller transition depends sensitively on the underlying shell structure and is usually distributed among many states in the neighbouring nucleus. Here we report measurements of the half-life and decay energy for the decay of (100)Sn, the heaviest doubly magic nucleus with equal numbers of protons and neutrons. In the ß-decay of (100)Sn, a large fraction of the strength is observable because of the large decay energy. We determine the largest Gamow-Teller strength so far measured in allowed nuclear ß-decay, establishing the 'superallowed' nature of this Gamow-Teller transition. The large strength and the low-energy states in the daughter nucleus, (100)In, are well reproduced by modern, large-scale shell model calculations.

11.
Phys Rev Lett ; 114(21): 212301, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26066429

RESUMO

Results on the production of the double strange cascade hyperon Ξ^{-} are reported for collisions of p(3.5 GeV)+Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. For the first time, subthreshold Ξ^{-} production is observed in proton-nucleus interactions. Assuming a Ξ^{-} phase-space distribution similar to that of Λ hyperons, the production probability amounts to P_{Ξ^{-}}=[2.0±0.4(stat)±0.3(norm)±0.6(syst)]×10^{-4} resulting in a Ξ^{-}/(Λ+Σ^{0}) ratio of P_{Ξ^{-}}/P_{Λ+Σ^{0}}=[1.2±0.3(stat)±0.4(syst)]×10^{-2}. Available model predictions are significantly lower than the measured Ξ^{-} yield.

12.
Gesundheitswesen ; 76(1): 44-7, 2014 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-23632821

RESUMO

BACKGROUND: General practitioners serve as important multipliers for seasonal influenza vaccination in risk groups such as elderly or chronically ill persons, for whom vaccination is recommended in Germany by the Standing Committee on Vaccination (STIKO). Moreover, physicians are a target group for influenza vaccination themselves. METHODS: Data from 1 590 telephone interviews were analysed. The study population comprised private physicians from 4 different disciplines (general and internal medicine, gynaecology, paediatrics). We assessed seasonal and pandemic vaccination coverage, attitudes and informational needs related to vaccination in general, and opinions about the pandemic situation 2009. RESULTS: Of the interviewed physicians, 61% stated that they have been vaccinated against seasonal influenza regularly. Main reasons for not/only occasionally having received a flu shot were: the belief that seasonal influenza vaccination is not necessary for them (78%) or having forgotten about the vaccination (28%). The interviewed physicians expressed a great demand for active information on STIKO recommendations and certain aspects of the seasonal influenza vaccination. There was a significant association between physicians' own influenza vaccination status and the provision of vaccination information materials, utilisation of a data management system for the vaccination of patients, and active vaccination reminders in the physicians' office. In 2009/10, almost 60% had received a pandemic influenza A(H1N1) vaccination. A major barrier to vaccine uptake was the mistrust in the safety of H1N1 vaccines (stated by 54% of non-vaccinees). Information for the public and physicians by the German public health authorities during the pandemic was rather critically appraised by the respondents. CONCLUSION: Compared to other subgroups of health-care workers, among private physicians seasonal and pandemic vaccine uptake was rather high. The physicians' need for more information on vaccination topics can be met by intensified publishing and communication activities of STIKO and by using existing physician-information channels.


Assuntos
Atitude do Pessoal de Saúde , Clínicos Gerais/estatística & dados numéricos , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Prática Privada/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Feminino , Alemanha/epidemiologia , Letramento em Saúde , Humanos , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias/estatística & dados numéricos , Padrões de Prática Médica , Estações do Ano , Vacinação/estatística & dados numéricos
13.
Phys Rev Lett ; 111(24): 242503, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24483648

RESUMO

The E1 strength distribution in 68Ni has been investigated using Coulomb excitation in inverse kinematics at the R3B-LAND setup and by measuring the invariant mass in the one- and two-neutron decay channels. The giant dipole resonance and a low-lying peak (pygmy dipole resonance) have been observed at 17.1(2) and 9.55(17) MeV, respectively. The measured dipole polarizability is compared to relativistic random phase approximation calculations yielding a neutron-skin thickness of 0.17(2) fm. A method and analysis applicable to neutron-rich nuclei has been developed, allowing for a precise determination of neutron skins in nuclei as a function of neutron excess.

14.
Clin Microbiol Infect ; 26(8): 1090.e7-1090.e13, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31843655

RESUMO

OBJECTIVES: There are few data available regarding the clinical course of tick-borne encephalitis virus (TBEV) vaccination breakthrough infections. The published studies suggest that vaccination breakthrough infections may have a more severe course than native TBEV infection in unvaccinated individuals-potentially due to antibody-dependent enhancement. Here we report a large analysis of vaccination breakthrough infections. METHODS: This retrospective analysis was based on a national surveillance dataset spanning the years 2001-2018. Variables reflecting disease severity, such as 'CNS symptoms', 'myelitis', 'fatal outcome' and 'hospitalization' were analysed as well as general epidemiological variables. Cases were categorized as 'unvaccinated' or 'ever vaccinated', the latter category including cases with at least one dose of a TBEV vaccine. RESULTS: A total of 6073 notified TBEV infection cases were included in our analysis. Sufficient data on vaccination status were available for 95.1% of patients (5777/6073); of these, 5298 presented with a native infection. A total of (334/5777) cases developed an infection despite having been vaccinated at least once. Comparing unvaccinated patients with those with at least one vaccination, we find an odds ratio (OR) 2.73, (95% confidence interval (CI) 0.79-9.50) regarding the variable fatal outcome that did not reach statistical significance. Analysing the clinical variables 'CNS symptoms' and 'myelitis', there is no difference between these groups (OR 0.86, 95% CI 0.68-1.08; and OR 1.30, 95% CI 0.74-2.27 respectively). Patients who were vaccinated and had an assumed protection at symptom onset (n = 100) had a higher risk for the development of myelitic symptoms (OR 2.21, 95% CI 1.01-4.86]) than unvaccinated patients. CONCLUSION: Our findings could neither verify that vaccination breakthrough infections might cause a more severe disease than native infections nor prove a clear antibody-dependent enhancement phenomenon. It remains unclear whether the increased myelitis risk in a subgroup of vaccinated patients is a true effect or confounded.


Assuntos
Encefalite Transmitida por Carrapatos/epidemiologia , Mielite/epidemiologia , Vacinação/estatística & dados numéricos , Vacinas Virais/administração & dosagem , Adulto , Idoso , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/imunologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mielite/microbiologia , Vigilância da População , Estudos Retrospectivos , Índice de Gravidade de Doença , Vacinas Virais/imunologia
16.
Technol Health Care ; 25(2): 171-186, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27689558

RESUMO

BACKGROUND: The non-image-forming effects of luminous radiation on people with intellectual disabilities or dementia received attention from researchers. Such studies, however, have generally been conducted using disparate methodologies which precludes generalization and reproducibility. OBJECTIVE: The aim of this study was to determine the practical applicability of measurement devices for studies investigating non-image-forming effects of luminous radiation, specifically for people with intellectual disabilities or dementia. METHODS: In three experiments, ten cognitive impaired people and thirty-nine unaffected subjects participated by wearing one or more portable devices. Six devices were assessed in total. Measurement data was accompanied with user experiences obtained from questionnaires, interviews and observations in order to assess the devices on practical and comfort issues. RESULTS: On average, the devices worn by the cognitive impaired subjects were not experienced as annoying or irritating. No significant differences are found between genders and for one of the portable devices significantly less annoyance was reported by the cognitive impaired participants compared to the unaffected group of participants. INNOVATIVE SOLUTION: The three phases of the research process in towards measuring personal luminous exposures are: selection of the most suitable portable device, application of the assessment method, and the application of the device in the (pilot) study. CONCLUSIONS: However, the findings of this study suggest that inaccuracies potentially caused by practical and comfort issues associated with the portable devices need to be considered.


Assuntos
Disfunção Cognitiva , Luz , Medições Luminescentes/instrumentação , Ritmo Circadiano
17.
Biochim Biophys Acta ; 1065(2): 217-24, 1991 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-2059653

RESUMO

The interaction of the non-enveloped plant viruses TMV (rod-shaped) and CCMV (spherical) and of their coat proteins in several well-defined aggregation states, with artificial membranes was investigated to study the early stages of the cellular infection process. Information about the separate steps in the interaction mechanisms was obtained by employing three assays, performed as a function of vesicle size, net membrane charge, pH and ionic strength. The assays allow to discriminate between aggregation of vesicles (turbidity assay) and membrane destabilization (vesicle leakage assay and lipid mixing assay). The aggregation of the vesicles is a result of electrostatic interactions between the viral material and vesicles surface (cross-linking), while the destabilization of the membrane is a result of penetration or bilayer disruption by hydrophobic protein domains. TMV virions and its coat protein, and CCMV virions, due to their net negative charge, predominantly interact with positively charged membranes. The coat protein of CCMV was found to interact with negatively charged membranes, an interaction that can be assigned to its basical N-terminal sequence. Changing the aggregational state of the viral coat proteins yielded most significant interactions in case of TMV coat protein aggregated in the disk form and CCMV coat protein aggregated in empty capsids with oppositely charged membranes. These protein aggregates are found to be the best compromise between efficiency (capacity of the protein to bridge vesicles and destabilize their membranes) and concentration of protein aggregates. The results are discussed with respect to previously proposed biological models of the early stages of plant virus infection.


Assuntos
Capsídeo/metabolismo , Lipossomos/metabolismo , Fosfolipídeos/metabolismo , Vírus de Plantas/metabolismo , Eletroquímica , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Substâncias Macromoleculares , Nefelometria e Turbidimetria , Concentração Osmolar , Tamanho da Partícula , Ácidos Fosfatídicos/metabolismo , Fosfatidilcolinas/metabolismo , Fosfolipídeos/química , Espectrometria de Fluorescência
18.
Photochem Photobiol ; 74(2): 237-45, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11547561

RESUMO

We describe a series of new long-wave absorbing and fluorescing cyanine dyes and labels (based on a general logic for the design of such dyes), their spectra, covalent and noncovalent linkage to proteins, their use in single molecule detection (SMD) and as donors and acceptors, respectively, in fluorescence resonance energy transfer studies. The new labels represent water-soluble and reactive fluorophores whose quantum yields increase substantially if noncovalently or covalently bound to proteins. Due to their strong absorptions between 550 and 700 nm they are excitable by light-emitting diodes or diode lasers. Their high absorbances (epsilon around 100,000) and adequate fluorescence quantum yields (phi up to 0.68 if bound to proteins) along with their availability as reactive NHS esters make them viable labels for proteins and oligomers, e.g. in context with SMD or fluorescence energy transfer immunoassay which is demonstrated for the system HSA/anti-HSA.


Assuntos
Corantes Fluorescentes/química , Proteínas/química , Fluorimunoensaio/métodos , Humanos , Técnicas In Vitro , Lasers , Fotoquímica , Albumina Sérica/análise , Albumina Sérica/química , Espectrometria de Fluorescência
19.
Dtsch Med Wochenschr ; 138(28-29): 1451-7, 2013 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-23821446

RESUMO

BACKGROUND: Pertussis vaccination for risk-groups (e. g. healthcare workers, employees of communal facilities, or persons with close contact to infants) has been recommended in Germany since 2001. In 2009, single-dose acellular pertussis (ap) vaccination was recommended for all adults at the next tetanus-diphtheria (Td) booster. Study aims were to assess 1) pertussis vaccination coverage in adults, and 2) use of tetanus-containing combination vaccines in hospitals. METHODS: For 1) we analysed data from two population-based telephone surveys conducted among adults in Germany in 2009/2010 (GEDA09: n = 21,262; GEDA10: n = 22,050). Factors associated with vaccination were identified by logistic regression analyses. For 2) a questionnaire survey of 133 hospital pharmacies serving 454 German hospitals was undertaken for the year 2007. RESULTS: Overall, 5.9% (95% confidence interval [CI] 5.5-6.3%) of GEDA10 participants reported up-to-date pertussis vaccination (ap-vaccination in past 10 years). In risk-groups, vaccination coverage was 10.7% (95%-CI 9.8-11.7%). Residence in former East-Germany and younger age were independently associated with an adequate vaccination status. Contrary to prevailing recommendations, ~75% of tetanus vaccines were administered as monovalent rather than Td- (or Tdap-)combination vaccines in hospitals. CONCLUSIONS: In light of high pertussis-incidence and low vaccination coverage in German adults, improvement of pertussis vaccine uptake is vital, e. g. through awareness campaigns targeting both physicians in private practice and hospitals.


Assuntos
Promoção da Saúde , Programas de Imunização/estatística & dados numéricos , Vacina contra Coqueluche/administração & dosagem , Coqueluche/prevenção & controle , Adolescente , Adulto , Estudos Transversais , Feminino , Alemanha , Inquéritos Epidemiológicos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Revisão da Utilização de Recursos de Saúde , Coqueluche/epidemiologia , Coqueluche/transmissão , Adulto Jovem
20.
Afr J Psychiatry (Johannesbg) ; 14(4): 273-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22038424

RESUMO

This article aims to describe the difference between descriptive and dynamic psychiatry. As part of the latter every psychiatrist should be able to construct a psychodynamic formulation. A psychodynamic formulation, an indication of psychological mindedness, helps the psychiatrist to recognize the unique, personal aspects of the illness and the life of the patient. The formulation furthermore helps with the initial orientation towards the patient: it anticipates and predicts how the patient might interact with the psychiatrist and how defenses and underlying conflicts will manifest themselves in treatment. The formulation can therefore be very useful in the treatment of any patient, since it can help to understand and manage the patient's attitude towards being prescribed medication, as well as compliance and prognosis and serve as an initial guide in the psychotherapy. The psychodynamic formulation is unfortunately seldom incorporated in the psychiatric presentation of patients; guidelines are therefore given to especially help psychiatric trainees with the construction of such a formulation.


Assuntos
Transtornos Mentais/terapia , Psiquiatria/métodos , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Humanos , Transtornos Mentais/psicologia , Cooperação do Paciente/psicologia , Relações Médico-Paciente
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