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1.
J Gen Virol ; 105(5)2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38767608

RESUMO

Herpesviruses establish a well-adapted balance with their host's immune system. Despite this co-evolutionary balance, infections can lead to severe disease including neurological disorders in their natural host. In horses, equine herpesvirus 1 (EHV-1) causes respiratory disease, abortions, neonatal foal death and myeloencephalopathy (EHM) in ~10 % of acute infections worldwide. Many aspects of EHM pathogenesis and protection from EHM are still poorly understood. However, it has been shown that the incidence of EHM increases to >70 % in female horses >20 years of age. In this study we used old mares as an experimental equine EHV-1 model of EHM to identify host-specific factors contributing to EHM. Following experimental infection with the neuropathogenic strain EHV-1 Ab4, old mares and yearling horses were studied for 21 days post-infection. Nasal viral shedding and cell-associated viremia were assessed by quantitative PCR. Cytokine/chemokine responses were evaluated in nasal secretions and cerebrospinal fluid (CSF) by Luminex assay and in whole blood by quantitative real-time PCR. EHV-1-specific IgG sub-isotype responses were measured by ELISA. All young horses developed respiratory disease and a bi-phasic fever post-infection, but only 1/9 horses exhibited ataxia. In contrast, respiratory disease was absent in old mares, but all old mares developed EHM that resulted in euthanasia in 6/9 old mares. Old mares also presented significantly decreased nasal viral shedding but higher viremia coinciding with a single fever peak at the onset of viremia. According to clinical disease manifestation, horses were sorted into an EHM group (nine old horses and one young horse) and a non-EHM group (eight young horses) for assessment of host immune responses. Non-EHM horses showed an early upregulation of IFN-α (nasal secretions), IRF7/IRF9, IL-1ß, CXCL10 and TBET (blood) in addition to an IFN-γ upregulation during viremia (blood). In contrast, IFN-α levels in nasal secretions of EHM horses were low and peak levels of IRF7, IRF9, CXCL10 and TGF-ß (blood) coincided with viremia. Moreover, EHM horses showed significantly higher IL-10 levels in nasal secretions, peripheral blood mononuclear cells and CSF and higher serum IgG3/5 antibody titres compared to non-EHM horses. These results suggest that protection from EHM depends on timely induction of type 1 IFN and upregulation cytokines and chemokines that are representative of cellular immunity. In contrast, induction of regulatory or TH-2 type immunity appeared to correlate with an increased risk for EHM. It is likely that future vaccine development for protection from EHM must target shifting this 'at-risk' immunophenotype.


Assuntos
Citocinas , Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Animais , Cavalos , Herpesvirus Equídeo 1/imunologia , Feminino , Doenças dos Cavalos/virologia , Doenças dos Cavalos/imunologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Citocinas/sangue , Citocinas/imunologia , Anticorpos Antivirais/sangue , Eliminação de Partículas Virais , Viremia/imunologia , Viremia/veterinária , Imunoglobulina G/sangue
2.
J Eur Acad Dermatol Venereol ; 37(11): 2355-2361, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37356045

RESUMO

BACKGROUND: Increasing evidence has sparked a debate on the loss of sensitivity of scabies mites to conventional permethrin therapy. Mutations in the voltage-sensitive sodium channels (VSSC) were associated with knockdown resistance (kdr) in many arthropods, but have never been identified in Sarcoptes scabiei variatio (var.) hominis mites. OBJECTIVES: To identify factors contributing to therapy failure. METHODS: Sixty-seven mites were collected from 64 scabies-infested patients in Vienna, Austria, of whom 85.9% were refractory to prior permethrin-based treatments, and genotyped for the presence of nucleotide polymorphisms in Domain II of the VSSC, known to be associated with kdr. Information regarding previous antiscabietic therapies, decontamination procedures and possible re-infestations by contacts as well as the response to re-imposed therapies were obtained. RESULTS: Sequence alignment comparisons revealed previously unidentified mutations in the coding region of Domain II of the VSSC. A novel A1663T transversion was detected in 97.0% of the mites, resulting in a non-synonymous substitution from methionine to leucine, M918L, a mutation known to confer kdr in other arthropods. In addition, a synonymous G1659A transition was identified in one mite, which otherwise showed a nucleotide sequence identical to the wild-type reference. No major inconsistencies were observed within the previous therapeutic and decontamination procedures, which could have accounted for the observed non-responsiveness to permethrin-based therapies. Subsequent cure of infestation was achieved in 65.6% of the participants, predominantly by combination therapies with topical permethrin and systemic ivermectin. However, in 14.6% of the cured cases, permethrin monotherapy sufficed for eradication of scabies, albeit in some cases prolonged exposure was necessary. CONCLUSIONS: The kdr-associated M918L mutation in the VSSC gene has now emerged in S. scabiei var. hominis mites. Hence, loss of sensitivity to permethrin due to kdr-type resistance may be more prevalent than anticipated and may be decisive for the therapy responsiveness of scabies-infested patients.


Assuntos
Artrópodes , Inseticidas , Escabiose , Animais , Humanos , Permetrina/farmacologia , Permetrina/uso terapêutico , Sarcoptes scabiei/genética , Escabiose/tratamento farmacológico , Inseticidas/farmacologia , Inseticidas/uso terapêutico , Mutação , Canais de Sódio/genética , Canais de Sódio/uso terapêutico
3.
J Eur Acad Dermatol Venereol ; 35(10): 2022-2026, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34146354

RESUMO

BACKGROUND: Chronic sun damage in the background is common in pigmented actinic keratoses and Bowen's disease (pAK/BD). While explainable artificial intelligence (AI) demonstrated increased background attention for pAK/BD, humans frequently miss this clue in dermatoscopic images because they tend to focus on the lesion. AIM: To analyse whether perilesional sun damage is a robust diagnostic clue for pAK/BD and if teaching this clue to dermatoscopy users improves their diagnostic accuracy. METHODS: We assessed the interrater agreement and the frequency of perilesional sun damage in 220 dermatoscopic images and conducted a reader study with 124 dermatoscopy users. The readers were randomly assigned to one of two online tutorials; one tutorial pointed to perilesional sun damage as a clue to pAK/BD (group A) the other did not (group B). In both groups, we compared the frequencies of correct diagnoses before and after receiving the tutorial. RESULTS: The frequency of perilesional sun damage was higher in pAK/BD than in other types of pigmented skin lesions and interrater agreement was good (kappa = 0.675). The diagnostic accuracy for pAK/BD improved in both groups of readers (group A: +16.1%, 95%-CI: 9.5-22.7; group B: +13.1%; 95%-CI: 7.1-19.0; P for both <0.001), but the overall accuracy improved only in group A from (59.1% (95%-CI: 55.0-63.1) to 63.5% (95%-CI: 59.5-67.6); P = 0.002). CONCLUSION: Perilesional sun damage is a good clue to differentiate pAK/BD from other pigmented skin lesions in dermatoscopic images, which could be useful for teledermatology. Knowledge of this clue improves the accuracy of dermatoscopy users, which demonstrates that insights from explainable AI can be used to train humans.


Assuntos
Doença de Bowen , Ceratose Actínica , Transtornos da Pigmentação , Neoplasias Cutâneas , Inteligência Artificial , Doença de Bowen/diagnóstico por imagem , Humanos , Ceratose Actínica/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico
4.
Orthopade ; 50(9): 763-774, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-34415371

RESUMO

Stress reactions and fractures represent an important differential diagnostic entity, especially in patients active in sports. The lower extremities have predilection sites for stress fractures, which require special treatment in the context of the underlying risk factors. Clinically, patients usually complain of stress-dependent pain in the affected region and sport activities are mostly limited or even impossible. The detection of acute stress fractures is usually missed by conventional X­ray within the first 4-6 weeks. The gold standard diagnostic tool is magnetic resonance imaging (MRI). Depending on the location, a distinction must be made between low-risk and high-risk stress fractures. Low-risk fractures show a high healing rate after conservative treatment including load and stress reduction as well as avoiding risk factors. High-risk fractures can take a complicated course under conservative treatment measures and in some cases, surgical intervention is required.


Assuntos
Fraturas de Estresse , Esportes , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/terapia , Humanos , Extremidade Inferior , Imageamento por Ressonância Magnética , Radiografia
5.
Unfallchirurg ; 124(7): 526-535, 2021 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-34170360

RESUMO

Avulsion injuries of the gluteus medius and gluteus minimus muscles represent a diagnostic and therapeutic challenge. Such injuries are rarely to be expected in high-energy trauma. Degenerative damage or iatrogenic injuries in the context of hip surgery are more frequently identified as the cause. Clinically, in addition to lateral hip pain, limping is an important finding and depends on the extent of the tendon damage. In addition to the medical history and clinical examination, imaging by means of sonography and, above all, magnetic resonance imaging (MRI, possibly with artifact-reduced sequences in the presence of an endoprosthesis) are diagnostically groundbreaking. Therapeutically, a stepwise approach is indicated according to the extent of rupture and quality of the gluteal tendon and muscle tissues. Specific conservative training regimens, mini-open/endoscopic anatomic reconstruction techniques in cases of gluteal muscle integrity and muscle transfer techniques as salvage option with chronic mass ruptures are available. The common goal is the restoration of everyday occupational and private activities to regain the quality of life.


Assuntos
Qualidade de Vida , Tendões , Nádegas/cirurgia , Quadril , Humanos , Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/cirurgia
6.
Public Health Nutr ; 23(14): 2494-2500, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32456727

RESUMO

OBJECTIVE: We aimed to assess the validity of maternal recall of exclusive breastfeeding (EBF) at 3 months obtained 12 months after childbirth. DESIGN: A population-based birth cohort study. The gold standard is maternal report of EBF at the age of 3 months (yes or no) and age of introduction of other foods in the infant's diet. EBF was considered when the mother reported that no liquid, semi-solid or solid food was introduced up to that moment. The variable to be validated was obtained at 12 months after childbirth when the mother was asked about the age of food introduction. The prevalence of EBF at 3 months, and sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and accuracy of 12-month recall with 95 % CI were calculated. SETTING: Pelotas, Brazil. PARTICIPANTS: 3700 mothers of participants of the Pelotas 2004 Birth Cohort. RESULTS: The prevalence of EBF at 3 months was 27·8 % (95 % CI 26·4, 29·3) and 49·0 % (95 % CI 47·4, 50·6) according to gold standard and maternal recall, respectively. The sensitivity of maternal recall at 12 months was 98·3 % (95 % CI 97·4, 99·0), specificity 70·0 % (95 % CI 68·2, 71·7), PPV 55·8 % (95 % CI 53·4, 58·1), NPV 99·1 % (95 % CI 98·6, 99·5) and accuracy 77·9 % (95 % CI 76·6, 79·2). When the analyses were stratified by maternal and infant characteristics, the sensitivity remained around 98 %, and the specificity ranged from 64·4 to 81·8 %. CONCLUSIONS: EBF recalled at the end of the first year of infant's life is a valid measure to be used in epidemiological investigations.


Assuntos
Aleitamento Materno , Rememoração Mental , Mães , Brasil , Estudos de Coortes , Feminino , Humanos , Lactente , Gravidez
7.
Adv Gerontol ; 32(5): 787-794, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32145171

RESUMO

Although falls are more prevalent as ageing proceeds, it cannot be assumed that they happen due to ageing alone. The retrospective cohort study of data was targeted to make an analysis of prevalence of falls in anaemic patients in comparison to the non-anaemic elderly admitted to the acute geriatric department and evaluation of pertinent influence of age, gender and immobility on occurrence of falls. During the considered period of four years (2012-2016) the authors treated 9 363 elderly patients aged 79,9±8,6 years (in the majority of them 65+ years). Among them there were 8 809 non-anaemic and subgroup of 551 old anaemic patients (aged 81±7 years) with decreased haemoglobin (<110 g/l). Falls at hospital admission in average was present in 1 766 non-anaemic persons (20%) in comparison to 380 falls among anaemic patients (68,6%). Prevalence in anaemic subgroup is statistically significant higher (p<0,005). Also relation between falls and age, ADL and MMSE test and mobility is highly statistically significant (p<0,001). Meaningfully higher is occurrence of repeated falls in the anaemic subgroup in comparison to the non-anaemic one (41,2 vs 1,7%). The occurrence of falls in female gender in comparison to men is statistically significant higher in non-anaemic patients, not in anaemic group. Authors emphasize that anaemia appears to us as significant risk factor for falls in the elderly.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Anemia/complicações , Hospitalização , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Prevalência , Estudos Retrospectivos
8.
Nano Lett ; 17(10): 5950-5955, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28906119

RESUMO

Ultralight mechanical resonators based on low-dimensional materials are well suited as exceptional transducers of minuscule forces or mass changes. However, the low dimensionality also provides a challenge to minimize resistive losses and heating. Here, we report on a novel approach that aims to combine different two-dimensional (2D) materials to tackle this challenge. We fabricated a heterostructure mechanical resonator consisting of few layers of niobium diselenide (NbSe2) encapsulated by two graphene sheets. The hybrid membrane shows high quality factors up to 245,000 at low temperatures, comparable to the best few-layer graphene mechanical resonators. In contrast to few-layer graphene resonators, the device shows reduced electrical losses attributed to the lower resistivity of the NbSe2 layer. The peculiar low-temperature dependence of the intrinsic quality factor points to dissipation over two-level systems which in turn relax over the electronic system. Our high sensitivity readout is enabled by coupling the membrane to a superconducting cavity which allows for the integration of the hybrid mechanical resonator as a sensitive and low loss transducer in future quantum circuits.

9.
Adv Gerontol ; 30(5): 703-708, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29322737

RESUMO

The aim was to compare an occurrence of acute PE in hospitalized patients 65+ years old with diabetes mellitus (DM) with those without any DM. It was a retrospective analysis of data collected in documentation of patients who were hospitalized at the geriatric department in the years 2007-2015. In this period we had 11 947 patients of an average age of 79,9±8,5 years (min - 65, max - 103 years). Out of this number there were 4 069 diabetics. Acute PE was found in 344 patients of an average age 80,3±7,4 years. 121 of them died (35,3%) and 223 survived (64,7%). From total patients 88 were diabetics with PE. Mortality on PE did not influence the presence of DM. She was the same in both groups of patients (p=NS) - with and without DM. RESULTS: Prevalence PE in the hospitalized 65+ years old was 2,9%. Mortality of PE among all the hospitalized 65+ was 1,0%. Higher prevalence of PE was found in non-diabetics - 3,2%, as compared to the diabetics - 2,3% (p<0,025). The average age of patients with diabetes both with and without PE was lower as compared to the non-diabetics (p<0,01). Among risk factors we found significantly more frequently obesity in the diabetics as compared to the non-diabetics both surviving (p<0,001) and those who died (p<0,05). The most important risk factor of PE was in all the patient's immobility. One risk factor appeared in the set of survivors more frequently in the non-diabetics as compared to the diabetics (p<0,05). Simultaneous occurrence of three risk factors appeared more frequently in the surviving diabetics (p<0,001) as compared to the non-diabetics. Although overall presence of risk factors was higher in the diabetics, PE prevalence in the DM patients was lower as compared to the non-diabetics. The immobility in general was the most important risk factor for PE occurrence, in the diabetics then also obesity.


Assuntos
Diabetes Mellitus/epidemiologia , Pacientes Internados , Embolia Pulmonar/epidemiologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Obesidade/epidemiologia , Prevalência , Embolia Pulmonar/mortalidade , Estudos Retrospectivos , Fatores de Risco , Comportamento Sedentário
10.
Orthopade ; 46(1): 78-84, 2017 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-27921130

RESUMO

BACKGROUND: Certification according to EndoCert in the field of arthroplasty in Germany aims at standardization of treatment and with this optimization of its quality. However, huge capital investment and efforts are necessary. There are currently more than 400 certified centres in Germany. Our Department of Orthopaedics at a German medical school was certified in the pilot phase. The aim of this study was to analyse whether there was a difference in the quality in the year after the certification. A second aim was to analyse whether the defined quality criteria are adequate for a university hospital. MATERIALS AND METHODS: The quality criteria as defined by EndoCert were analysed in the year before (2011) and after certification (2012). The observed complications were noted for 1 year postoperatively. The clinical outcome was analysed with Western Ontario and McMaster University Osteoarthritis Index Score (WOMAC) 1 year postoperatively. RESULTS: There was no difference concerning the criteria analysed, including the clinical outcome in the year before and that after certification. In both years, nearly all criteria could be reached except the operation time and the infection rate in hip and knee revision surgery. CONCLUSION: Certification did not lead to a measurable change of the quality of care. Nearly all criteria, except the infection rate in revision arthroplasty (required: less than 3% at 1 year postop.) and the operation duration could be fulfilled. This rate as well as the operation duration should be revised. Certification according to EndoCert is an important tool to prove quality care, however big efforts and capital are needed. The criteria should be constantly revised and reduced, as these resources should not be missed in patient care.


Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Artroplastia de Quadril/normas , Artroplastia do Joelho/estatística & dados numéricos , Artroplastia do Joelho/normas , Certificação/normas , Complicações Pós-Operatórias/epidemiologia , Melhoria de Qualidade/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Prevalência , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Resultado do Tratamento
11.
Orthopade ; 46(2): 142-147, 2017 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-28083683

RESUMO

BACKGROUND: In case of hip revision arthroplasty, one component (cup/stem) is often well fixed and does not need to be exchanged. The newly implanted component needs to be compatible with the well-fixed implant. The combination of implants from different companies leads to "mix and match" or even mismatch between the implants. OBJECTIVES AND METHODS: The objective of this work was to describe possible combinations including their specifications that need to be considered in partial exchange of hip prostheses. For this purpose the literature, surgical techniques of companies and judgements concerning this topic were analysed and our own results and experiences were included. RESULTS AND CONCLUSIONS: Partial revision arthroplasty can be challenging and needs to be planned in detail. In case of isolated cup or inlay revision with exchange of a modular head the cone of the stem needs to be identified. A ceramic head may be used in revision with a titanium sleeve even from a different company as long as they are compatible. Patients however need to give their informed consent for this mix and match procedure. This procedure is done frequently and good study results support this, however from a juristic point of view a definite recommendation cannot be given. If the inlay of a cup is replaced, the original inlay should be used. If this is not available anymore, it can be manufactured as a special product in many cases. If this is also not possible, an inlay can also be cemented into a well-fixed cup. Biomechanical and clinical studies support this off-label technique. In case of an isolated exchange of the stem with a ceramic inlay that is retained in a well-fixed cup, the revision stem and ceramic head need to be from the same company as the cup. In case of ceramic fracture, a ceramic head with a titanium sleeve should be combined with a PE or ceramic inlay, a metal head or inlay should never be used.


Assuntos
Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Prótese de Quadril , Osteoartrite do Quadril/cirurgia , Reoperação/instrumentação , Reoperação/métodos , Acetabuloplastia/instrumentação , Acetabuloplastia/métodos , Acetábulo/cirurgia , Terapia Combinada , Medicina Baseada em Evidências , Humanos , Osteotomia/instrumentação , Osteotomia/métodos , Desenho de Prótese , Procedimentos de Cirurgia Plástica/instrumentação , Procedimentos de Cirurgia Plástica/métodos , Resultado do Tratamento
12.
Ann Dermatol Venereol ; 144(3): 182-190, 2017 Mar.
Artigo em Francês | MEDLINE | ID: mdl-28011091

RESUMO

BACKGROUND: Autoimmune bullous diseases (AIBD) may cause chronic oral lesions that progress insidiously. AIMS: To provide recommendations for optimal oral-dental management of patients presenting AIBD with oral involvement. PATIENTS AND METHODS: In the absence of scientific studies with high levels of proof, these recommendations have been drawn up at two meetings by a committee of experts on AIBD comprising 7 dermatologists, 1 stomatologist, 1 maxillofacial surgeon, 2 odontologists and 4 parodontologists. RESULTS: The oral lesions associated with AIBD may be classified into three grades of severity: severe (generalised erosive gingivitis affecting at least 30% of dental sites), moderate (localised erosive gingivitis affecting less than 30% of dental sites) and controlled (no erosive oral lesions). Good oral-dental hygiene suited to the severity of the oral lesions, must be practised continually by these patients so as to avoid the formation of dental plaque, which aggravates symptoms. Dental and parodontal care must be considered in accordance with the severity grade of the oral lesions: in severe cases, the dental plaque must be eliminated manually with a curette, but several types of care (descaling, treatment for tooth decay, non-urgent extractions, etc.) must be suspended until the grade of severity is moderate or until the disease is stabilised.


Assuntos
Doenças da Boca/patologia , Doenças da Boca/terapia , Higiene Bucal , Penfigoide Bolhoso/patologia , Penfigoide Bolhoso/terapia , Consenso , França , Humanos , Doenças da Boca/imunologia , Higiene Bucal/métodos , Índice de Higiene Oral , Educação de Pacientes como Assunto/métodos , Penfigoide Bolhoso/imunologia , Índice de Gravidade de Doença
13.
Nano Lett ; 15(7): 4417-22, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26060894

RESUMO

We report transport measurements on a quantum dot in a partly suspended carbon nanotube. Electrostatic tuning allows us to modify and even switch "on" and "off" the coupling to the quantized stretching vibration across several charge states. The magnetic-field dependence indicates that only the two-electron spin-triplet excited state couples to the mechanical motion, indicating mechanical coupling to both the valley degree of freedom and the exchange interaction, in contrast to standard models.

14.
J Environ Manage ; 183(Pt 3): 601-612, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27633144

RESUMO

Acid mine drainage (AMD) impacted waters are a worldwide concern for the mining industry and countries dealing with this issue; both active and passive technologies are employed for the treatment of such waters. Mussel shell bioreactors (MSB) represent a passive technology that utilizes waste from the shellfish industry as a novel substrate. The aim of this study is to provide insight into the biogeochemical dynamics of a novel full scale MSB for AMD treatment. A combination of water quality data, targeted geochemical extractions, and metagenomic analyses were used to evaluate MSB performance. The MSB raised the effluent pH from 3.4 to 8.3 while removing up to ∼99% of the dissolved Al, and Fe and >90% Ni, Tl, and Zn. A geochemical gradient was observed progressing from oxidized to reduced conditions with depth. The redox conditions helped define the microbial consortium that consists of a specialized niche of organisms that influence elemental cycling (i.e. complex Fe and S cycling). MSB technology represents an economic and effective means of full scale, passive AMD treatment that is an attractive alternative for developing economies due to its low cost and ease of implementation.


Assuntos
Exoesqueleto/microbiologia , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Metais/metabolismo , Enxofre/metabolismo , Poluentes Químicos da Água/metabolismo , Ácidos/metabolismo , Animais , Bactérias/genética , Bivalves , Concentração de Íons de Hidrogênio , Metais/análise , Consórcios Microbianos , Mineração , Análise de Componente Principal , RNA Ribossômico 16S/genética , Enxofre/análise , Poluentes Químicos da Água/análise
15.
Phys Rev Lett ; 114(25): 255501, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26197134

RESUMO

Structural rearrangements within single molecules occur on ultrafast time scales. Many aspects of molecular dynamics, such as the energy flow through excited states, have been studied using spectroscopic techniques, yet the goal to watch molecules evolve their geometrical structure in real time remains challenging. By mapping nuclear motions using femtosecond x-ray pulses, we have created real-space representations of the evolving dynamics during a well-known chemical reaction and show a series of time-sorted structural snapshots produced by ultrafast time-resolved hard x-ray scattering. A computational analysis optimally matches the series of scattering patterns produced by the x rays to a multitude of potential reaction paths. In so doing, we have made a critical step toward the goal of viewing chemical reactions on femtosecond time scales, opening a new direction in studies of ultrafast chemical reactions in the gas phase.

16.
Nano Lett ; 14(5): 2854-60, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24745803

RESUMO

Graphene is an attractive material for nanomechanical devices because it allows for exceptional properties, such as high frequencies, quality factors, and low mass. An outstanding challenge, however, has been to obtain large coupling between the motion and external systems for efficient readout and manipulation. Here, we report on a novel approach, in which we capacitively couple a high-Q graphene mechanical resonator (Q ≈ 10(5)) to a superconducting microwave cavity. The initial devices exhibit a large single-photon coupling of ∼10 Hz. Remarkably, we can electrostatically change the graphene equilibrium position and thereby tune the single photon coupling, the mechanical resonance frequency, and the sign and magnitude of the observed Duffing nonlinearity. The strong tunability opens up new possibilities, such as the tuning of the optomechanical coupling strength on a time scale faster than the inverse of the cavity line width. With realistic improvements, it should be possible to enter the regime of quantum optomechanics.

17.
Bratisl Lek Listy ; 116(7): 408-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26286242

RESUMO

OBJECTIVES: With advancing age, the degree of dependency and occurrence of great geriatric syndromes (GS), also referred to as geriatric giants, grow substantially. DESIGN: The prospective cohort study was aimed at conducting an analysis and comparison of geriatric syndromes (geriatric giants) among different age groups at admission to the acute geriatric department. SETTING, PARTICIPANTS: Between 1995 and 2012, we had altogether 12,210 elderly patients at an average age of 80.5 ± 7.0 y (range 65-103 y) hospitalised at the Department of Geriatrics. We divided the patient set into three different age subgroups (65-74 y; 75-84 y and ≥85 y; e.g. 21.4%; 47.9% and 30.7%) and compared the results among them. RESULTS: 3,787 persons (31.0%) were without any GS. The growing tendency of the occurrence of all geriatric syndromes in combinations with increased age (p<0.001) is obvious. Their occurrence in the above mentioned different age sets was examined in relation to individual geriatric syndromes and sex (female and male), namely falls 22.0%, 27.8%, 39.9% and 20.5%, 27.0%, 36.1%; immobility 26.4%, 29.3%, 42.5% and 30.3%, 30.1% and 39.2%; incontinence 38.4%, 50.6%, 69.5% and 38.2%, 47.4%, 61.8 %; dementia and cognitive impairment 13.4%, 23.4%, 38.1% and 15.8%, 24.3%, 33.2% respectively. Age cut-off for geriatric syndromes occurrence based on ROC analysis is 83.5-84.5 y for females and 78.5-82.5 y for males. CONCLUSION: The occurrence of geriatric giants increasing with age and female gender is of crucial importance not only for individuals and families but also for demands on costs of health and social care in oncoming decades (Tab. 6, Fig. 3, Ref. 52).


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Transtornos Cognitivos/epidemiologia , Incontinência Fecal/epidemiologia , Incontinência Urinária/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , República Tcheca/epidemiologia , Feminino , Geriatria , Humanos , Masculino , Estudos Prospectivos , Síndrome
18.
Rapid Commun Mass Spectrom ; 28(11): 1258-64, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24760566

RESUMO

RATIONALE: The use of stable nitrogen (N) isotope ratios (δ(15)N values) in dendroecological studies is often preceded by an extraction procedure using organic solvents to remove mobile N compounds from tree-rings. Although these mobile N compounds may be capable of distorting potential environmental signals in the tree-ring δ(15)N values, recent investigations question the necessity of such an extraction. METHODS: We used an on-going experiment with simulated elevated N deposition previously labelled with (15)N, in conjunction with control trees, to investigate the necessity of extracting mobile N compounds (using a rapid extraction procedure) for tree-ring δ(15)N and δ(13)C studies, as well as N and C concentration analyses. In addition, we examined the magnitude of radial redistribution of N across tree-rings of Norway spruce (Picea abies). RESULTS: The (15)N label, applied in 1995/96, was found in tree-rings as far back as 1951, although the increased N availability did not cause any significant relative increase in tree growth. The rapid extraction procedure had no significant effect on tree-ring δ(15)N or δ(13)C values in either labelled or control trees, or on N concentration. The C concentrations, however, were significantly higher after extraction in control samples, with the opposite effect observed in labelled samples. CONCLUSIONS: Our results indicate that the extraction of mobile N compounds through the rapid extraction procedure is not necessary prior to the determination of Norway spruce δ(15)N or δ(13)C values in dendrochemical studies. δ(15)N values, however, must be interpreted with great care, particularly when used as a proxy for the N status of trees, due to the very high mobility of N within the tree stem sapwood of Norway spruce over several decades.


Assuntos
Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Nitrogênio/metabolismo , Picea/metabolismo , Árvores/metabolismo , Transporte Biológico , Isótopos de Carbono/metabolismo , Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Picea/química , Árvores/química
19.
Nanotechnology ; 25(3): 035703, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24345726

RESUMO

We report on the influence of low gamma irradiation (10(4) Gy) on the noise properties of individual carbon nanotube (CNT) field-effect transistors (FETs) with different gate configurations and two different dielectric layers, SiO2 and Al2O3. Before treatment, strong generation-recombination (GR) noise components are observed. These data are used to identify several charge traps related to dielectric layers of the FETs by determining their activation energy. Investigation of samples with a single SiO2 dielectric layer as well as with two dielectric layers allows us to separate traps for each of the two dielectric layers. We reveal that each charge trap level observed in the side gate operation splits into two levels in top gate operation due to a different potential profile along the CNT channel. After gamma irradiation, only reduced flicker noise is registered in the noise spectra, which indicates a decrease of the number of charge traps. The mobility, which is estimated to be larger than 2 × 10(4) cm(2) V(-1) s(-1) at room temperature, decreases only slightly after radiation treatment, demonstrating high radiation hardness of the CNTs. Finally, we study the influence of Schottky barriers at the metal-nanotube interface on the transport properties of FETs, analyzing the behavior of the flicker noise component.

20.
Adv Gerontol ; 27(3): 519-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25827001

RESUMO

In gerontology diabetes mellitus (DM) is clinically the most frequent and extremely serious metabolic disorder. DM is an important health issue across the globe. With increasing life expectancy physicians are called upon to manage diabetes in the elderly more often. Senior patients suffer predominantly from the type 2 DM--T2DM (70+ up to 90-95%). Apart from genetic predisposition and an environmental influence, nutritional habits, modern lifestyle, stress and minor physical activity are of particular importance. Treatment options for T2DM in the elderly are diet, physical activity, various oral anti-diabetic drugs and insulin. At the start of treatment should primarily take into account: patient's age; self-sufficiency; late micro- and macro-vascular complications; social status; nutritional assessment (incl. dental status); other handicaps--psychic, motoric, visual and aural. Especially in frail, elderly patients, there should be less emphasis on strict glycaemic control than on avoiding malnutrition and hypoglycemia and achieving the best possible quality of life. Therapy of DM in this population is tightly connected with significant risks of micro- and macrovascular complications on one hand, and possible problems of the treatment (e.g. hypoglycemia) with intensive control on the other hand. To realize a comprehensive approach to therapy of diabetes in the old age a holistic approach with main aim improving quality of life is necessary.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/psicologia , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Qualidade de Vida
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