Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Risk Anal ; 39(1): 125-139, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-28749563

RESUMO

This article presents a flood risk analysis model that considers the spatially heterogeneous nature of flood events. The basic concept of this approach is to generate a large sample of flood events that can be regarded as temporal extrapolation of flood events. These are combined with cumulative flood impact indicators, such as building damages, to finally derive time series of damages for risk estimation. Therefore, a multivariate modeling procedure that is able to take into account the spatial characteristics of flooding, the regionalization method top-kriging, and three different impact indicators are combined in a model chain. Eventually, the expected annual flood impact (e.g., expected annual damages) and the flood impact associated with a low probability of occurrence are determined for a study area. The risk model has the potential to augment the understanding of flood risk in a region and thereby contribute to enhanced risk management of, for example, risk analysts and policymakers or insurance companies. The modeling framework was successfully applied in a proof-of-concept exercise in Vorarlberg (Austria). The results of the case study show that risk analysis has to be based on spatially heterogeneous flood events in order to estimate flood risk adequately.

2.
Northeast Nat (Steuben) ; 26(3): 545-560, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31341382

RESUMO

Lyme disease is an emerging infectious disease of public health concern in the northeastern United States. The disease's vector, Ixodes scapularis (Say) (Blacklegged Tick), has increased its range in the past twenty years. In its newly endemic northern range there have been few studies of the Blacklegged Tick's habitat associations. From 2016-2018, we sampled for nymphal Blacklegged Ticks in the Champlain Valley and Green Mountains of Addison County, Vermont, and tested them for Borrelia burgdorferi, the Lyme disease agent. We found 10 times more ticks in the Champlain Valley than in the Green Mountains. Nymphal infection prevalence was 0.21 and did not vary by year or region. The difference in tick density reported has public health consequences, as Vermont has one of the highest rates of Lyme disease in the United States.

3.
Proc Natl Acad Sci U S A ; 112(42): 12911-6, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26438839

RESUMO

The wing scales of the Green Hairstreak butterfly Callophrys rubi consist of crystalline domains with sizes of a few micrometers, which exhibit a congenitally handed porous chitin microstructure identified as the chiral triply periodic single-gyroid structure. Here, the chirality and crystallographic texture of these domains are investigated by means of electron tomography. The tomograms unambiguously reveal the coexistence of the two enantiomeric forms of opposite handedness: the left- and right-handed gyroids. These two enantiomers appear with nonequal probabilities, implying that molecularly chiral constituents of the biological formation process presumably invoke a chiral symmetry break, resulting in a preferred enantiomeric form of the gyroid structure. Assuming validity of the formation model proposed by Ghiradella H (1989) J Morphol 202(1):69-88 and Saranathan V, et al. (2010) Proc Natl Acad Sci USA 107(26):11676-11681, where the two enantiomeric labyrinthine domains of the gyroid are connected to the extracellular and intra-SER spaces, our findings imply that the structural chirality of the single gyroid is, however, not caused by the molecular chirality of chitin. Furthermore, the wing scales are found to be highly textured, with a substantial fraction of domains exhibiting the <001> directions of the gyroid crystal aligned parallel to the scale surface normal. Both findings are needed to completely understand the photonic purpose of the single gyroid in gyroid-forming butterflies. More importantly, they show the level of control that morphogenesis exerts over secondary features of biological nanostructures, such as chirality or crystallographic texture, providing inspiration for biomimetic replication strategies for synthetic self-assembly mechanisms.


Assuntos
Borboletas/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Microscopia Eletrônica de Transmissão e Varredura , Asas de Animais/ultraestrutura
4.
Cerebrovasc Dis ; 43(1-2): 76-81, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27951536

RESUMO

BACKGROUND: Both, acute ischemic stroke (AIS) and hemorrhage stroke (intracerebral hemorrhage, ICH) require early attention but different treatment strategies. Plasma glial fibrillary acidic protein (GFAP) levels were found to be elevated in ICH patients after they arrived in the hospital. Because treatment options differed, we sought to determine whether GFAP can be used to accurately differentiate between of AIS and ICH in the prehospital setting. METHODS: We assessed acute stroke patients in the Stroke Emergency Mobile (STEMO). STEMO is a stroke ambulance staffed by a specialized team including a neurologist and equipped with a computed tomography scanner plus a point-of-care laboratory. The STEMO ambulance is integrated in the emergency medical system of Berlin, Germany. Following prehospital stroke diagnosis, blood was drawn and subsequently analysed using research assays from Roche diagnostics. The clinical accuracy of plasma GFAP was tested using a cut-off value of 0.29 ng/ml. RESULTS: Blood samples of 74 patients were analysed. Twenty-five patients had ICH (mean age 69 ± 11 years, median National Institutes of Health Stroke Scale (NIHSS) 15) and 49 IS (mean age 75 ± 10 years, median NIHSS 6). Nine ICH (0 IS patients) had GFAP-levels above 0.29 ng/ml. The sensitivity and specificity of GFAP for differentiating between ICH and AIS were 36.0 and 100%. The sensitivity for ICH volume >15 ml was 61.5%. ICH patients without GFAP elevation had significantly smaller hemorrhage volumes (median 4.5 vs. 37.6 ml, p = 0.004) and were less likely to deteriorate (19 vs. 56%, p = 0.087). CONCLUSIONS: GFAP levels >0.29 ng/ml were seen only in ICH, thus confirming the diagnosis of ICH during prehospital care. However, sensitivity is low particularly in smaller hemorrhages.


Assuntos
Isquemia Encefálica/diagnóstico , Hemorragia Cerebral/diagnóstico , Serviços Médicos de Emergência , Proteína Glial Fibrilar Ácida/sangue , Acidente Vascular Cerebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Ambulâncias , Berlim , Biomarcadores/sangue , Isquemia Encefálica/sangue , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/terapia , Hemorragia Cerebral/sangue , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/terapia , Prestação Integrada de Cuidados de Saúde , Diagnóstico Diferencial , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurologistas , Equipe de Assistência ao Paciente , Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Tomografia Computadorizada por Raios X , Regulação para Cima
5.
Stroke ; 47(8): 2136-40, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27328702

RESUMO

BACKGROUND AND PURPOSE: Specialized computed tomography-equipped stroke ambulances shorten time to intravenous thrombolysis in acute ischemic stroke by starting treatment before hospital arrival. Because of longer travel-time-to-scene, time benefits of this concept are expected to diminish with longer distances from base station to scene. METHODS: We used data from the Prehospital Acute Neurological Treatment and Optimization of Medical Cares in Stroke (PHANTOM-S) trial comparing time intervals between patients for whom a specialized stroke ambulance (stroke emergency mobile) was deployed and patients with conventional emergency medical service. Expected times from base station to scene had been calculated beforehand using computer algorithms informed by emergency medical service routine data. Four different deployment zones with-75% probability-expected arrival within 4, 8, 12, and 16 minutes and total population coverage of ≈1.3 million inhabitants were categorized for stroke emergency mobile deployment. We analyzed times from alarm-to-arrival at scene, to start of intravenous thrombolysis and from onset-to-intravenous thrombolysis. RESULTS: Corresponding to the size of the respective catchment zone, the number of patients cared increased with distance (zone 1: n=30, zone 2: n=127, zone 3: n=156, and zone 4: n=217). Although time to stroke emergency mobile arrival increased with distance (mean: 8.0, 12.5, 15.4, and 18.4 minutes in zones 1-4), time from alarm-to-intravenous thrombolysis (mean: 41.8 versus 76.5; 50.2 versus 79.1; 54.5 versus 76.6; and 59.3 versus 78.0 minutes, respectively; all P<0.01) remained shorter in the stroke emergency mobile group across all zones. CONCLUSIONS: In a metropolitan area such as Berlin, time benefits justify a specialized stroke ambulance service up to a mean travel time of 18 minutes from base station. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01382862.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Serviços Médicos de Emergência , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Ambulâncias , Isquemia Encefálica/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Fatores de Tempo , Tempo para o Tratamento , Tomografia Computadorizada por Raios X
6.
Stroke ; 46(3): 740-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25634000

RESUMO

BACKGROUND AND PURPOSE: Specialized management of patients with stroke is not available in all hospitals. We evaluated whether prehospital management in the Stroke Emergency Mobile (STEMO) improves the triage of patients with stroke. METHODS: STEMO is an ambulance staffed with a specialized stroke team and equipped with a computed tomographic scanner and point-of-care laboratory. We compared the prehospital triage of patients with suspected stroke at dispatcher level who either received STEMO care or conventional care. We assessed transport destination in patients with different diagnoses. Status at hospital discharge was used as short-term outcome. RESULTS: From May 2011 to January 2013, 1804 of 6182 (29%) patients received STEMO care and 4378 of 6182 (71%) patients conventional care. Two hundred forty-five of 2110 (11.6%) patients with cerebrovascular events were sent to hospitals without Stroke Unit in conventional care when compared with 48 of 866 (5.5%; P<0.01%) patients in STEMO care. In patients with ischemic stroke, STEMO care reduced transport to hospitals without Stroke Unit from 10.1% (151 of 1497) to 3.9% (24 of 610; P<0.01). The delivery rate of patients with intracranial hemorrhage to hospitals without neurosurgery department was 43.0% (65 of 151) in conventional care and 11.3% (7 of 62) in STEMO care (P<0.01). There was a slight trend toward higher rates of patients discharged home in neurological patients when cared by STEMO (63.5% versus 60.8%; P=0.096). CONCLUSIONS: The triage of patients with cerebrovascular events to specialized hospitals can be improved by STEMO ambulances. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01382862.


Assuntos
Ambulâncias , Tratamento de Emergência/métodos , Hospitalização , Acidente Vascular Cerebral/terapia , Transporte de Pacientes/métodos , Triagem/métodos , Idoso , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Neurologia/métodos , Alta do Paciente , Terapia Trombolítica/métodos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Stroke ; 46(9): 2426-31, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26251255

RESUMO

BACKGROUND AND PURPOSE: Copeptin levels are increased in patients diagnosed with stroke and other vascular diseases. Copeptin elevation is associated with adverse outcome, predicts re-events in patients with transient ischemic attack and is used in ruling-out acute myocardial infarction. We evaluated whether copeptin can also be used as a diagnostic marker in the prehospital stroke setting. METHODS: We prospectively examined patients with suspected stroke on the Stroke Emergency Mobile-an ambulance that is equipped with computed tomography and point-of-care laboratory. A blood sample was taken from patients immediately after arrival. We analyzed copeptin levels in patients with final hospital-based diagnosis of stroke or stroke mimics as well as in vascular or nonvascular patients. In addition, we examined the associations of symptom onset with copeptin levels and the prognostic value of copeptin in patients with stroke. RESULTS: Blood samples of 561 patients were analyzed. No significant differences were seen neither between cerebrovascular (n=383) and other neurological (stroke mimic; n=90) patients (P=0.15) nor between vascular (n=391) and nonvascular patients (n=170; P=0.57). We could not detect a relationship between copeptin levels and time from onset to blood draw. Three-month survival status was available in 159 patients with ischemic stroke. Copeptin levels in nonsurviving patients (n=8: median [interquartile range], 27.4 [20.2-54.7] pmol/L) were significantly higher than in surviving patients (n=151: median [interquartile range], 11.7 [5.2-30.9] pmol/L; P=0.024). CONCLUSIONS: In the prehospital setting, copeptin is neither appropriate to discriminate between stroke and stroke mimic patients nor between vascular and nonvascular patients. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01382862. The Pre-Hospital Acute Neurological Therapy and Optimization of Medical Care in Stroke Patients study (PHANTOM-S) was registered (NCT01382862). This sub-study was observational and not registered separately, therefore.


Assuntos
Isquemia Encefálica/sangue , Glicopeptídeos/sangue , Acidente Vascular Cerebral/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Serviços Médicos de Emergência/métodos , Feminino , Humanos , Ataque Isquêmico Transitório/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico
8.
Ann Neurol ; 73(1): 136-40, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23378326

RESUMO

Temporal delay in blood oxygenation level-dependent (BOLD) signals may be sensitive to perfusion deficits in acute stroke. Resting-state functional magnetic resonance imaging (rsfMRI) was added to a standard stroke MRI protocol. We calculated the time delay between the BOLD signal at each voxel and the whole-brain signal using time-lagged correlation and compared the results to mean transit time derived using bolus tracking. In all 11 patients, areas exhibiting significant delay in BOLD signal corresponded to areas of hypoperfusion identified by contrast-based perfusion MRI. Time delay analysis of rsfMRI provides information comparable to that of conventional perfusion MRI without the need for contrast agents.


Assuntos
Circulação Cerebrovascular/fisiologia , Imageamento por Ressonância Magnética/métodos , Descanso/fisiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Phys Chem Chem Phys ; 16(2): 383-95, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24002354

RESUMO

The development of sensors capable of detecting particles and radiation with both high time and high positional resolution is key to improving our understanding in many areas of science. Example applications of such sensors range from fundamental scattering studies of chemical reaction mechanisms through to imaging mass spectrometry of surfaces, neutron scattering studies aimed at probing the structure of materials, and time-resolved fluorescence measurements to elucidate the structure and function of biomolecules. In addition to improved throughput resulting from parallelisation of data collection - imaging of multiple different fragments in velocity-map imaging studies, for example - fast image sensors also offer a number of fundamentally new capabilities in areas such as coincidence detection. In this Perspective, we review recent developments in fast image sensor technology, provide examples of their implementation in a range of different experimental contexts, and discuss potential future developments and applications.

10.
JAMA ; 311(16): 1622-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24756512

RESUMO

IMPORTANCE: Time to thrombolysis is crucial for outcome in acute ischemic stroke. OBJECTIVE: To determine if starting thrombolysis in a specialized ambulance reduces delays. DESIGN, SETTING, AND PARTICIPANTS: In the Prehospital Acute Neurological Treatment and Optimization of Medical care in Stroke Study (PHANTOM-S), conducted in Berlin, Germany, we randomly assigned weeks with and without availability of the Stroke Emergency Mobile (STEMO) from May 1, 2011, to January 31, 2013. Berlin has an established stroke care infrastructure with 14 stroke units. We included 6182 adult patients (STEMO weeks: 44.3% male, mean [SD] age, 73.9 [15.0] y; control weeks: 45.2% male, mean [SD] age, 74.3 [14.9] y) for whom a stroke dispatch was activated. INTERVENTIONS: The intervention comprised an ambulance (STEMO) equipped with a CT scanner, point-of-care laboratory, and telemedicine connection; a stroke identification algorithm at dispatcher level; and a prehospital stroke team. Thrombolysis was started before transport to hospital if ischemic stroke was confirmed and contraindications excluded. MAIN OUTCOMES AND MEASURES: Primary outcome was alarm-to-thrombolysis time. Secondary outcomes included thrombolysis rate, secondary intracerebral hemorrhage after thrombolysis, and 7-day mortality. RESULTS: Time reduction was assessed in all patients with a stroke dispatch from the entire catchment area in STEMO weeks (3213 patients) vs control weeks (2969 patients) and in patients in whom STEMO was available and deployed (1804 patients) vs control weeks (2969 patients). Compared with thrombolysis during control weeks, there was a reduction of 15 minutes (95% CI, 11-19) in alarm-to-treatment times in the catchment area during STEMO weeks (76.3 min; 95% CI, 73.2-79.3 vs 61.4 min; 95% CI, 58.7-64.0; P < .001). Among patients for whom STEMO was deployed, mean alarm-to-treatment time (51.8 min; 95% CI, 49.0-54.6) was shorter by 25 minutes (95% CI, 20-29; P < .001) than during control weeks. Thrombolysis rates in ischemic stroke were 29% (310/1070) during STEMO weeks and 33% (200/614) after STEMO deployment vs 21% (220/1041) during control weeks (differences, 8%; 95% CI, 4%-12%; P < .001, and 12%, 95% CI, 7%-16%; P < .001, respectively). STEMO deployment incurred no increased risk for intracerebral hemorrhage (STEMO deployment: 7/200; conventional care: 22/323; adjusted odds ratio [OR], 0.42, 95% CI, 0.18-1.03; P = .06) or 7-day mortality (9/199 vs 15/323; adjusted OR, 0.76; 95% CI, 0.31-1.82; P = .53). CONCLUSIONS AND RELEVANCE: Compared with usual care, the use of ambulance-based thrombolysis resulted in decreased time to treatment without an increase in adverse events. Further studies are needed to assess the effects on clinical outcomes. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01382862.


Assuntos
Isquemia Encefálica/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Terapia Trombolítica , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Ambulâncias , Serviços Médicos de Emergência , Feminino , Humanos , Hemorragias Intracranianas/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Análise de Sobrevida , Telemedicina , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/métodos , Fatores de Tempo , Tomografia Computadorizada por Raios X
11.
Angew Chem Int Ed Engl ; 53(51): 14201-5, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25327934

RESUMO

The high-pressure hydrogenation of commercially available anatase or anatase/rutile TiO2 powder can create a photocatalyst for H2 evolution that is highly effective and stable without the need for any additional co-catalyst. This activation effect cannot be observed for rutile; however, for anatase/rutile mixtures, a strong synergistic effect can be found (similar to results commonly observed for noble-metal-decorated TiO2). EPR and PL measurements indicated the intrinsic co-catalytic activation of anatase TiO2 to be due to specific defect centers formed during hydrogenation. These active centers can be observed specifically for high-pressure hydrogenation; other common reduction treatments do not result in this effect.

13.
Ecology ; 104(6): e4039, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36960918

RESUMO

Following a disturbance, dispersal shapes community composition as well as ecosystem structure and function. For fungi, dispersal is often wind or mammal facilitated, but it is unclear whether these pathways are complementary or redundant in the taxa they disperse and the ecosystem functions they provide. Here, we compare the diversity and morphology of fungi dispersed by wind and three rodent species in recently harvested forests using a combination of microscopy and Illumina sequencing. We demonstrate that fungal communities dispersed by wind and small mammals differ in richness and composition. Most wind-dispersed fungi are wood saprotrophs, litter saprotrophs, and plant pathogens, whereas fungi dispersed in mammal scat are primarily mycorrhizal, soil saprotrophs, and unspecified saprotrophs. We note substantial dispersal of truffles and agaricoid mushrooms by small mammals, and dispersal of agaricoid mushrooms, crusts, and polypores by wind. In addition, we find mammal-dispersed spores are larger than wind-dispersed spores. Our findings suggest that wind- and small-mammal-facilitated dispersal are complementary processes and highlight the role of small mammals in dispersing mycorrhizal fungi, particularly following disturbances such as timber harvest.


Assuntos
Ecossistema , Micorrizas , Animais , Vento , Florestas , Mamíferos , Roedores , Microbiologia do Solo , Fungos , Solo , Esporos Fúngicos
14.
Stroke ; 43(8): 2086-90, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22693132

RESUMO

BACKGROUND AND PURPOSE: Pre- and intrahospital time delays are major concerns in acute stroke care. Telemedicine-equipped ambulances may improve time management and identify patients with stroke eligible for thrombolysis by an early prehospital stroke diagnosis. The aims of this study were (1) to develop a telestroke ambulance prototype; (2) to test the reliability of stroke severity assessment; and (3) to evaluate its feasibility in the prehospital emergency setting. METHODS: Mobil, real-time audio-video streaming telemedicine devices were implemented into advanced life support ambulances. Feasibility of telestroke ambulances and reliability of the National Institutes of Health Stroke Scale assessment were tested using current wireless cellular communication technology (third generation) in a prehospital stroke scenario. Two stroke actors were trained in simulation of differing right and left middle cerebral artery stroke syndromes. National Institutes of Health Stroke Scale assessment was performed by a hospital-based stroke physician by telemedicine, by an emergency physician guided by telemedicine, and "a posteriori" on the basis of video documentation. RESULTS: In 18 of 30 scenarios, National Institutes of Health Stroke Scale assessment could not be performed due to absence or loss of audio-video signal. In the remaining 12 completed scenarios, interrater agreement of National Institutes of Health Stroke Scale examination between ambulance and hospital and ambulance and "a posteriori" video evaluation was moderate to good with weighted κ values of 0.69 (95% CI, 0.51-0.87) and 0.79 (95% CI, 0.59-0.98), respectively. CONCLUSION: Prehospital telestroke examination was not at an acceptable level for clinical use, at least on the basis of the used technology. Further technical development is needed before telestroke is applicable for prehospital stroke management during patient transport.


Assuntos
Ambulâncias , Serviços Médicos de Emergência/organização & administração , Acidente Vascular Cerebral/terapia , Telemedicina/organização & administração , Berlim , Telefone Celular , Sistemas Computacionais , Estudos de Viabilidade , Humanos , Variações Dependentes do Observador , Simulação de Paciente , Médicos , Projetos Piloto , Acidente Vascular Cerebral/diagnóstico , Terapia Trombolítica
15.
J Neurol Neurosurg Psychiatry ; 83(8): 776-84, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22696587

RESUMO

OBJECTIVE: Vascular lesions of the posterolateral thalamus typically result in a somatosensory syndrome in which some patients develop central neuropathic post-stroke pain (CPSP). Damage to the spinothalamic tract terminus is assumed to be a prerequisite for thalamic CPSP. At the nuclear level, it remains a matter of debate whether the ventral posterolateral nucleus (VPL) or the posterior portion of the ventral medial nucleus (VMpo) constitutes the decisive lesion site. The hypothesis of the study was that lesion location in thalamic CPSP patients differs from that in thalamic stroke patients without pain, and the aim was to identify whether this difference comprises the VPL and/or the VMpo. DESIGN: 30 patients with chronic thalamic stroke and a persistent contralateral somatosensory syndrome were examined. CPSP patients (n=18) were compared with non-pain control patients. By coregistration of a digitised thalamic atlas with T1 weighted MR images, lesion clusters were allocated to the thalamic nuclei. RESULTS: VPL was affected in both groups, but CPSP lesion clusters comprised the more posterior, inferior and lateral parts of the VPL compared with controls. Additional partial involvement of the VMpo was seen in only three pain patients. In three other pain patients, lesions involved neither the VPL nor the VMpo, but mainly affected the anterior pulvinar. CONCLUSION: This study specifies the role of the VPL in thalamic CPSP and shows that the posterolateratal and inferior parts in particular are critically lesioned in pain patients. In this thalamic subregion, afferents of the spinothalamic tract are known to terminate. In contrast, the data do not support a pivotal impact of the VMpo on thalamic CPSP.


Assuntos
Acidente Vascular Cerebral/patologia , Doenças Talâmicas/patologia , Tálamo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cefaleia/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Estudos Prospectivos , Distúrbios Somatossensoriais/etiologia , Distúrbios Somatossensoriais/patologia , Acidente Vascular Cerebral/complicações , Doenças Talâmicas/complicações , Núcleos Ventrais do Tálamo/patologia
16.
J Phys Chem A ; 116(45): 10897-903, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23102270

RESUMO

We present the first multimass velocity-map imaging data acquired using a new ultrafast camera designed for time-resolved particle imaging. The PImMS (Pixel Imaging Mass Spectrometry) sensor allows particle events to be imaged with time resolution as high as 25 ns over data acquisition times of more than 100 µs. In photofragment imaging studies, this allows velocity-map images to be acquired for multiple fragment masses on each time-of-flight cycle. We describe the sensor architecture and present bench-testing data and multimass velocity-map images for photofragments formed in the UV photolysis of two test molecules: Br(2) and N,N-dimethylformamide.

17.
J Med Entomol ; 59(1): 162-172, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642748

RESUMO

Tick-borne disease control and prevention have been largely ineffective compared to the control of other vector-borne diseases. Although control strategies exist, they are costly or ineffective at large spatial scales. We need tools to target these strategies to places of highest tick exposure risk. Here we present a geographic information system (GIS) method for mapping predicted tick exposure risk at a 200 m by 200 m resolution, appropriate for public health intervention. We followed the approach used to map tick habitat suitability over large areas. We used drag-cloth sampling to measure the density of nymphal blacklegged ticks (Ixodes scapularis, Say (Acari: Ixodidae)) at 24 sites in Addison and Rutland Counties, VT, United States. We used a GIS to average habitat, climatological, land-use/land-cover, and abiotic characteristics over 100 m, 400 m, 1,000 m, and 2,000 m buffers around each site to evaluate which characteristic at which buffer size best predicted density of nymphal ticks (DON). The relationships between predictor variables and DON were determined with random forest models. The 100 m buffer model performed best and explained 37.7% of the variation in DON, although was highly accurate at classifying sites as having below or above average DON. This model was applied to Addison County, VT, to predict tick exposure risk at a 200 m resolution. This GIS approach to map predicted DON over a small area with fine resolution, could be used to target public health campaigns and land management practices to reduce human exposure to ticks.


Assuntos
Ecossistema , Sistemas de Informação Geográfica , Ixodes , Saúde Pública , Animais , Feminino , Ixodes/crescimento & desenvolvimento , Doença de Lyme/transmissão , Masculino , Ninfa/crescimento & desenvolvimento , Densidade Demográfica , Vermont
18.
Proc Natl Acad Sci U S A ; 105(25): 8575-9, 2008 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-18562276

RESUMO

Many developmentally regulated genes contain a poised RNA polymerase II (Pol II) at their promoters under conditions where full-length transcripts are undetectable. It has been proposed that the transcriptional activity of such promoters is regulated at the elongation stage of Pol II transcription. In Drosophila, the heat-shock loci expressing the Hsp70 genes have been used as a model for the regulation of the transcriptional activity of poised Pol II. Drosophila ELL (dELL) is a Pol II elongation factor capable of stimulating the rate of transcription both in vivo and in vitro. Although ELL and the elongation factor Elongin A have indistinguishable effects on RNA polymerase in vitro, the loss-of-function studies indicate that these proteins are not redundant in vivo. In this article, we use RNAi to investigate the physiological properties of dELL and a dELL-associated factor (dEaf) in a living organism. Both ELL and Eaf are essential for fly development. dELL is recruited to heat shock loci upon induction, and its presence with Pol II at such loci is required for proper heat-shock gene expression. Consistent with a role in elongation, dELL knockdown reduces the levels of phosphorylated Pol II at heat-shock loci. This study implicates dELL in the expression of loci regulated by Pol II elongation.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica , RNA Polimerase II/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Masculino , Microscopia de Fluorescência , Interferência de RNA , Fatores de Transcrição/genética
19.
Neurol Res Pract ; 3(1): 1, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33499926

RESUMO

BACKGROUND: Routing of patients with intracerebral hemorrhage (ICH) and acute ischemic stroke (AIS) to the most appropriate hospital is challenging for emergency medical services particularly when specific treatment options are only provided by specialized hospitals and determination of the exact diagnosis is difficult. We aimed to develop a prehospital score - called prehospital-intracerebral hemorrhage score (ph-ICH score) - to assist in discriminating between both conditions. METHODS: The ph-ICH score was developed with data from patients treated aboard a mobile stroke unit in Berlin, Germany, between 2011 and 2013 (derivation cohort) and in 2018 (validation cohort). Diagnosis of ICH or AIS was established using clinical data and neuroradiological cerebral imaging. Diagnostic accuracy was measured with significance testing, Cohen's d and receiver-operating-characteristics. RESULTS: We analyzed 416 patients (32 ICH, 224 AIS, 41 transient ischemic attack, 119 stroke mimic) in the derivation cohort and 285 patients (33 ICH and 252 AIS) in the validation cohort. Systolic blood pressure, level of consciousness and severity of neurological deficits (i. e. certain items of the National Institutes of Health Stroke Scale) were used to calculate the ph-ICH score that showed higher values in the ICH compared to the AIS group (derivation cohort: 1.8 ± 1.2 vs. 1.0 ± 0.9 points; validation cohort: 1.8 ± 0.9 vs. 0.8 ± 0.7 points; d = 0.9 and 1.4, both p < 0.01). Receiver-operating-characteristics showed fair and good accuracy with an area under the curve of 0.71 for the derivation and 0.81 for the validation cohort. CONCLUSIONS: The ph-ICH score can assist medical personnel in the field to assess the likelihood of ICH and AIS in emergency patients.

20.
ACS Earth Space Chem ; 5(4): 785-800, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33889791

RESUMO

Alkyl nitrate (AN) and secondary organic aerosol (SOA) from the reaction of nitrate radicals (NO3) with isoprene were observed in the Simulation of Atmospheric PHotochemistry In a large Reaction (SAPHIR) chamber during the NO3Isop campaign in August 2018. Based on 15 day-long experiments under various reaction conditions, we conclude that the reaction has a nominally unity molar AN yield (observed range 90 ± 40%) and an SOA mass yield of OA + organic nitrate aerosol of 13-15% (with ∼50 µg m-3 inorganic seed aerosol and 2-5 µg m-3 total organic aerosol). Isoprene (5-25 ppb) and oxidant (typically ∼100 ppb O3 and 5-25 ppb NO2) concentrations and aerosol composition (inorganic and organic coating) were varied while remaining close to ambient conditions, producing similar AN and SOA yields under all regimes. We observe the formation of dinitrates upon oxidation of the second double bond only once the isoprene precursor is fully consumed. We determine the bulk partitioning coefficient for ANs (K p ∼ 10-3 m3 µg-1), indicating an average volatility corresponding to a C5 hydroxy hydroperoxy nitrate.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA