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1.
Brain ; 147(3): 1057-1074, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38153327

RESUMO

Incomplete reperfusion of the microvasculature ('no-reflow') after ischaemic stroke damages salvageable brain tissue. Previous ex vivo studies suggest pericytes are vulnerable to ischaemia and may exacerbate no-reflow, but the viability of pericytes and their association with no-reflow remains under-explored in vivo. Using longitudinal in vivo two-photon single-cell imaging over 7 days, we showed that 87% of pericytes constrict during cerebral ischaemia and remain constricted post reperfusion, and 50% of the pericyte population are acutely damaged. Moreover, we revealed ischaemic pericytes to be fundamentally implicated in capillary no-reflow by limiting and arresting blood flow within the first 24 h post stroke. Despite sustaining acute membrane damage, we observed that over half of all cortical pericytes survived ischaemia and responded to vasoactive stimuli, upregulated unique transcriptomic profiles and replicated. Finally, we demonstrated the delayed recovery of capillary diameter by ischaemic pericytes after reperfusion predicted vessel reconstriction in the subacute phase of stroke. Cumulatively, these findings demonstrate that surviving cortical pericytes remain both viable and promising therapeutic targets to counteract no-reflow after ischaemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Pericitos/fisiologia , Infarto Cerebral
2.
BMC Cancer ; 23(1): 508, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37277755

RESUMO

BACKGROUND: Benefit finding (BF) - the occurrence of positive life-changes in the aftermath of traumatic live events - has been repeatedly reported in prostate cancer (PCa) survivors, but it remains unclear in which way BF might vary over time. The current study aimed to investigate the extent of BF and associated factors in different phases of the survivorship continuum. METHODS: In this cross-sectional study, men affected by PCa who were either already treated with radical prostatectomy or going to be treated with radical prostatectomy at a large German PCa center were included. These men were stratified into four groups (prior to surgery, up to 12 months after surgery, 2-5 years and ≥ 6-10 years after surgery). BF was assessed using the German version of the 17-item Benefit Finding Scale (BFS). The items are rated on a five-point Likert scale ranging from 1 to 5. A total mean score ≥ 3 was considered as moderate-to-high BF. Associations with clinical and psychological factors were assessed in men presenting before and in those who participated after surgery. Multiple linear regression was applied to identify intendent determinants of BF. RESULTS: 2,298 men affected by PCa (mean age at survey: 69.5,SD = 8.2; median follow-up: 3 years (25th -75th percentile 0.5-7)) were included. 49.6% of men reported moderate-to-high BF. The mean BF score was 2.91 (SD = 0.92). BF reported by men before surgery did not differ significantly from BF reported by men in the years after surgery (p = 0.56). Higher BF prior to and following radical prostatectomy was associated with higher perceived severity of the disease (pre-surgery: ß = 0.188, p = 0.008; post-surgery: ß = 0.161, p = < 0.0001) and higher cancer-related distress (pre-surgery: ß ? 0.155, p = 0.03; post-surgery: ß = 0.089, p < 0.0001). Post radical prostatectomy BF was also associated with biochemical recurrence during follow-up (ß = 0.089, p = 0.001), and higher quality of life (ß = 0.124, p < 0.001). CONCLUSIONS: Many men affected by PCa perceive BF already soon after diagnosis. The subjective perception of threat or severity associated with the diagnosis of PCa is an essential factor for higher levels of BF, probably more important than objective indicators of the severity of the disease. The early onset of BF and the high degree of similarity of BF reported across the different phases of survivorship suggests that BF is, to a large extent, a dispositional personal characteristic and a cognitive strategy of positively coping with cancer.


Assuntos
Neoplasias da Próstata , Qualidade de Vida , Masculino , Humanos , Estudos Transversais , Neoplasias da Próstata/terapia , Próstata , Prostatectomia
3.
ChemSusChem ; 15(24): e202201323, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36214486

RESUMO

Oxygen is a molecule of utmost importance in our lives. Beside its vital role for the respiration and sustaining of organisms, oxygen is involved in numerous chemical and physical processes. Upon combination of the different forms of molecular oxygen species with various activation modes, substrates, and reaction conditions an extremely wide chemical space can be covered that enables rich applications of diverse oxygenation processes. This Review provides an instructive overview of the individual properties and reactivities of oxygen species and illustrates their importance in nature, everyday life, and in the context of chemical synthesis.


Assuntos
Oxigênio , Oxigênio/química
4.
Front Neurorobot ; 15: 749024, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744678

RESUMO

Spinal cord stimulation (SCS) is an established treatment for refractory pain syndromes and has recently been applied to improve locomotion. Several technical challenges are faced by surgeons during SCS lead implantation, particularly in the confined dorsal epidural spaces in patients with spinal degenerative disease, scarring and while targeting challenging structures such as the dorsal root ganglion. Magnetic navigation systems (MNS) represent a novel technology that uses externally placed magnets to precisely steer tethered and untethered devices. This innovation offers several benefits for SCS electrode placement, including enhanced navigation control during tip placement, and the ability to position and reposition the lead in an outpatient setting. Here, we describe the challenges of SCS implant surgery and how MNS can be used to overcome these hurdles. In addition to tethered electrode steering, we discuss the navigation of untethered micro- and nanorobots for wireless and remote neuromodulation. The use of these small-scale devices can potentially change the current standard of practice by omitting the need for electrode and pulse generator implantation or replacement. Open questions include whether small-scale robots can generate an electrical field sufficient to activate neuronal tissue, as well as testing precise navigation, placement, anchoring, and biodegradation of micro- and nanorobots in the in vivo environment.

5.
Front Robot AI ; 8: 652685, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113657

RESUMO

The Coronavirus disease 2019 (Covid-19) pandemic has brought the world to a standstill. Healthcare systems are critical to maintain during pandemics, however, providing service to sick patients has posed a hazard to frontline healthcare workers (HCW) and particularly those caring for elderly patients. Various approaches are investigated to improve safety for HCW and patients. One promising avenue is the use of robots. Here, we model infectious spread based on real spatio-temporal precise personal interactions from a geriatric unit and test different scenarios of robotic integration. We find a significant mitigation of contamination rates when robots specifically replace a moderate fraction of high-risk healthcare workers, who have a high number of contacts with patients and other HCW. While the impact of robotic integration is significant across a range of reproductive number R0, the largest effect is seen when R0 is slightly above its critical value. Our analysis suggests that a moderate-sized robotic integration can represent an effective measure to significantly reduce the spread of pathogens with Covid-19 transmission characteristics in a small hospital unit.

6.
ChemSusChem ; 14(16): 3325-3332, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34184836

RESUMO

The upcycling of waste biomass into valuable materials by resource-efficient chemical transformations is a prime objective for sustainable chemistry. This approach is demonstrated in a straightforward light-driven synthesis of polyols and polyurethane foams from the multi-ton waste products of cashew nut processing. The photo-oxygenation of cardanol from nutshell oil results in the formation of synthetically versatile hydroperoxides. The choice of the workup method (i. e., reduction, hydrogenation, epoxidation) enables access to a diverse range of alcohols with tunable alkene and OH functions. Condensation with isocyanates to give rigid polyurethane foams provides a resource-efficient waste-to-value chain that benefits from the availability of cardanol and installation of OH groups from aerial O2 .

7.
Proc Natl Acad Sci U S A ; 117(16): 8804-8812, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32253304

RESUMO

International carbon markets are an appealing and increasingly popular tool to regulate carbon emissions. By putting a price on carbon, carbon markets reshape incentives faced by firms and reduce the value of emissions. How effective are carbon markets? Observers have tended to infer their effectiveness from market prices. The general belief is that a carbon market needs a high price in order to reduce emissions. As a result, many observers remain skeptical of initiatives such as the European Union Emissions Trading System (EU ETS), whose price remained low (compared to the social cost of carbon). In this paper, we assess whether the EU ETS reduced [Formula: see text] emissions despite low prices. We motivate our study by documenting that a carbon market can be effective if it is a credible institution that can plausibly become more stringent in the future. In such a case, firms might cut emissions even though market prices are low. In fact, low prices can be a signal that the demand for carbon permits weakens. Thus, low prices are compatible with successful carbon markets. To assess whether the EU ETS reduced carbon emissions even as permits were cheap, we estimate counterfactual carbon emissions using an original sectoral emissions dataset. We find that the EU ETS saved about 1.2 billion tons of [Formula: see text] between 2008 and 2016 (3.8%) relative to a world without carbon markets, or almost half of what EU governments promised to reduce under their Kyoto Protocol commitments. Emission reductions in sectors covered under the EU ETS were higher.

8.
Sci Adv ; 3(5): e1602153, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28560328

RESUMO

This article assesses the socioeconomic effects of solar microgrids. The lack of access to electricity is a major obstacle to the socioeconomic development of more than a billion people. Off-grid solar technologies hold potential as an affordable and clean solution to satisfy basic electricity needs. We conducted a randomized field experiment in India to estimate the causal effect of off-grid solar power on electricity access and broader socioeconomic development of 1281 rural households. Within a year, electrification rates in the treatment group increased by 29 to 36 percentage points. Daily hours of access to electricity increased only by 0.99 to 1.42 hours, and the confidence intervals are wide. Kerosene expenditure on the black market decreased by 47 to 49 rupees per month. Despite these strong electrification and expenditure effects, we found no systematic evidence for changes in savings, spending, business creation, time spent working or studying, or other broader indicators of socioeconomic development.

9.
Beilstein J Org Chem ; 12: 1798-1811, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27829887

RESUMO

A home-built microreactor system for light-mediated biphasic gas/liquid reactions was assembled from simple commercial components. This paper describes in full detail the nature and function of the required building elements, the assembly of parts, and the tuning and interdependencies of the most important reactor and reaction parameters. Unlike many commercial thin-film and microchannel reactors, the described set-up operates residence times of up to 30 min which cover the typical rates of many organic reactions. The tubular microreactor was successfully applied to the photooxygenation of hydrocarbons (Schenck ene reaction). Major emphasis was laid on the realization of a constant and highly reproducible gas/liquid slug flow and the effective illumination by an appropriate light source. The optimized set of conditions enabled the shortening of reaction times by more than 99% with equal chemoselectivities. The modular home-made flow reactor can serve as a prototype model for the continuous operation of various other reactions at light/liquid/gas interfaces in student, research, and industrial laboratories.

10.
Transfusion ; 54(2): 376-83, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23772713

RESUMO

BACKGROUND: Immunoglobulin G (IgG) concentrates have recently been found to be contaminated with procoagulant impurities causing thromboembolic events (TEEs) in vivo. In this study the question was raised whether a thrombin generation assay (TGA) will be able to characterize IgG samples from the Austrian market with regard to their thrombogenic potential. STUDY DESIGN AND METHODS: A total of 44 IgG concentrates have been assayed by TGA employing pooled normal plasma and Factor (F)XI-deficient plasma (FXIdp). Furthermore, the prekallikrein activator assay including determination of blank values, size-exclusion chromatography, and further test systems required for batch release testing of IgG concentrates according to the European Pharmacopeia (Pharm. Eur.) were carried out. RESULTS: All samples complied with acceptance criteria stated in the Plarm. Eur. and/or prescribed by the marketing approval. One intravenous immunoglobulin (IVIG) involved in TEEs exceeded a threshold level of 350 nmol peak thrombin, which was not exceeded after change of manufacture and by all the other IVIGs tested. Two hyperimmune globulins revealed elevated peak thrombin levels of up to 810 nmol in FXI and up to 285 nmol in FXIdp. CONCLUSION: The study indicates that the TGA is able to reliably predict procoagulant activities probably associated with the presence of FXIa and potential thrombogenicity. Comparison of thrombin generation with product-specific acceptance criteria as well as variables from other test systems as amidolytic activity and molecular size can help to monitor IgG quality and manufacturing changes with regard to thrombogenicity.


Assuntos
Cromatografia em Gel/métodos , Fator XIIa/metabolismo , Imunoglobulinas Intravenosas/efeitos adversos , Trombina/biossíntese , Trombose/etiologia , Áustria , Contaminação de Medicamentos , Fator XIIa/análise , Humanos , Imunoglobulina G/efeitos adversos , Imunoglobulina G/sangue , Imunoglobulinas Intravenosas/sangue , Peso Molecular , Concentração Osmolar , Trombina/análise , Trombose/sangue , Trombose/imunologia
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