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1.
Sci Rep ; 13(1): 11150, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429957

RESUMO

This study presents a data-driven approach to identifying interpersonal motor synchrony states by analyzing hand movements captured from a 3D depth camera. Utilizing a single frame from the experiment, an XGBoost machine learning model was employed to differentiate between spontaneous and intentional synchrony modes with nearly [Formula: see text] accuracy. Our findings demonstrate a consistent pattern across subjects, revealing that movement velocity tends to be slower in synchrony modes. These insights support the notion that the relationship between velocity and synchrony is influenced by the cognitive load required for the task, with slower movements leading to higher synchrony in tasks demanding higher cognitive load. This work not only contributes to the limited literature on algorithms for identifying interpersonal synchrony but also has potential implications for developing new metrics to assess real-time human social interactions, understanding social interaction, and diagnosing and developing treatment strategies for social deficits associated with conditions such as Autism Spectrum Disorder.


Assuntos
Transtorno do Espectro Autista , Humanos , Interação Social , Algoritmos , Benchmarking , Mãos
2.
Food Chem ; 364: 130336, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34175634

RESUMO

Insect proteins have an earthy-like flavor and have not shown great flavor potential for food applications so far. In this study, insect proteins of cricket Acheta domesticus and mealworm Tenebrio molitor larvae were first enzymatically hydrolyzed using two peptidase preparations (Flavourzyme1000L and ProteaseA "Amano"2SD). Xylose was then added to facilitate Maillard reactions (30 min, T = 98 °C, 1% (w/v) xylose). A comprehensive sensory evaluation showed that both the hydrolysis and the Maillard reactions changed the flavor description of the samples significantly to more complex and savory-like taste profiles (27 descriptors for cricket and 39 descriptors for mealworm protein). In addition, 38 odor-active molecules were identified using gas chromatography-olfactometry (1 alcohol, 5 acids, 11 aldehydes, 5 ketones and 16 heterocyclic compounds). The results showed impressively that the flavoring potential of insect proteins was significantly enhanced with respective processing.


Assuntos
Gryllidae , Tenebrio , Animais , Aromatizantes , Produtos Finais de Glicação Avançada , Hidrolisados de Proteína
3.
J Cereb Blood Flow Metab ; 41(8): 1964-1977, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33461409

RESUMO

Alterations in the concentration of nitric oxide (NO) and L-arginine metabolites have been associated with the pathophysiology of different vascular diseases. Here, we describe striking changes in L-arginine metabolism after hemorrhagic stroke. Blood and cerebrospinal fluid (CSF) samples of patients with intracerebral hemorrhage (ICH) and/or intraventricular hemorrhage were collected over a ten-day period. Liquid chromatography-tandem mass spectrometry was used to quantify key substrates and products of L-arginine metabolizing enzymes as well as asymmetric (ADMA) and symmetric dimethylarginine (SDMA). Changes in the plasma were limited to early reductions in L-ornithine, L-lysine, and L-citrulline concentrations. Intrathecally, we observed signs of early NO synthase (NOS) upregulation followed by a decrease back to baseline accompanied by a rise in the level of its endogenous NOS-inhibitor ADMA. SDMA demonstrated increased levels throughout the observation period. For arginase, a pattern of persistently elevated activity was measured and arginine:glycine amidinotransferase (AGAT) appeared to be reduced in its activity at later time points. An early reduction in CSF L-arginine concentration was an independent risk factor for poor outcome. Together, these findings further elucidate pathophysiological mechanisms after ICH potentially involved in secondary brain injury and may reveal novel therapeutic targets.


Assuntos
Arginina/metabolismo , Hemorragia Cerebral/patologia , Idoso , Arginina/análogos & derivados , Arginina/sangue , Arginina/líquido cefalorraquidiano , Estudos de Casos e Controles , Hemorragia Cerebral/metabolismo , Cromatografia Líquida de Alta Pressão , Citrulina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Ornitina/sangue , Fatores de Risco , Espectrometria de Massas em Tandem , Regulação para Cima
4.
J Agric Food Chem ; 69(1): 368-376, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356225

RESUMO

The aim of this study was to investigate six food-grade peptidase preparations, namely, Flavourzyme 1000L, Protease P "Amano" 6SD, DeltazymAPS-M-FG, Promod278, ProteAX-K, and Peptidase R, regarding their use for the hydrolysis of soy, pea, and canola protein. The relationship between the specific peptidase activities and, first, the degree of hydrolysis, second, the free amino acid profiles of the hydrolysates, and, third, the corresponding taste of the hydrolysates was analyzed using a random forest model. The taste attributes bitter and umami were of special interest. The peptidase ProteAX-K was the biocatalyst most suited for the high umami and low bitter taste of the plant-based protein hydrolysates based on the experimental results and the random forest model.


Assuntos
Brassica napus/química , Aromatizantes/química , Glycine max/química , Peptídeo Hidrolases/química , Pisum sativum/química , Proteínas de Plantas/química , Humanos , Hidrólise , Paladar
5.
J Clin Med ; 9(12)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271854

RESUMO

Delayed cerebral ischemia (DCI) often causes poor long-term neurological outcome after subarachnoidal hemorrhage (SAH). Asymmetric dimethylarginine (ADMA) inhibits nitric oxide synthase (NOS) and is associated with DCI after SAH. We studied single nucleotide polymorphisms (SNPs) in the NOS3, DDAH1, DDAH2, PRMT1, and AGXT2 genes that are part of the L-arginine-ADMA-NO pathway, and their association with DCI. We measured L-arginine, ADMA and symmetric dimethylarginine (SDMA) in plasma and cerebrospinal fluid (CSF) of 51 SAH patients at admission; follow-up was until 30 days post-discharge. The primary outcome was the incidence of DCI, defined as new infarctions on cranial computed tomography, which occurred in 18 of 51 patients. Clinical scores did not significantly differ in patients with or without DCI. However, DCI patients had higher plasma ADMA and SDMA levels and higher CSF SDMA levels at admission. DDAH1 SNPs were associated with plasma ADMA, whilst AGXT2 SNPs were associated with plasma SDMA. Carriers of the minor allele of DDAH1 rs233112 had a significantly increased relative risk of DCI (Relative Risk = 2.61 (1.25-5.43), p = 0.002). We conclude that the DDAH1 gene is associated with ADMA concentration and the incidence of DCI in SAH patients, suggesting a pathophysiological link between gene, biomarker, and clinical outcome in patients with SAH.

6.
J Int Med Res ; 48(8): 300060520940450, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32842812

RESUMO

OBJECTIVES: Perioperative cardiovascular events remain an important factor that affects surgery outcome. We assessed if asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthesis, predicts perioperative risk, and if pre-operative supplementation with L-arginine/L-citrulline improves the plasma L-arginine/ADMA ratio. METHODS: In this prospective study, planned thoracic and/or abdominal surgery patients were randomized to receive L-arginine/L-citrulline (5 g/day) or placebo 1 to 5 days before surgery. We measured perioperative plasma ADMA and L-arginine levels. The primary outcome was a 30-day combined cardiovascular endpoint. RESULTS: Among 269 patients, 23 (8.6%) experienced a major adverse cardiovascular event. ADMA and C-reactive protein were significantly associated with the incidence of cardiovascular complications in the multivariable-adjusted analysis. The L-arginine plasma concentration was significantly higher on the day of surgery with L-arginine/L-citrulline supplementation compared with placebo. In patients with high pre-operative ADMA, there was a non-significant trend towards reduced incidence of the primary endpoint with L-arginine/L-citrulline supplementation (six vs. nine events). CONCLUSIONS: ADMA is a predictor of major adverse cardiovascular complications in the perioperative period for patients who are undergoing major abdominal and/or thoracic surgery. Supplementation with L-arginine/L-citrulline increased the L-arginine plasma concentration, enhanced the L-arginine/ADMA ratio, and induced a trend towards fewer perioperative events.


Assuntos
Arginina , Citrulina , Arginina/análogos & derivados , Proteína C-Reativa , Humanos , Estudos Prospectivos
7.
Mar Pollut Bull ; 135: 1072-1078, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30301003

RESUMO

Bioaccumulation of 2,4,6-trinitrotoluene (TNT) and its main metabolites 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) leaking from corroded munitions at a munitions dumping site (Kolberger Heide, Germany) was evaluated in transplanted blue mussels (Mytilus edulis). Six moorings with mussel bags were placed east and west at varying positions near the mine mound. In order to monitor any differences resulting from changing seasons, three exposure times were chosen. First exposure period: April-July 2016 (106 days); second exposure period: July-December 2016 (146 days); third exposure period: December 2016-March 2017 (92 days). We found amounts of 4-ADNT in mussel tissue ranging from 2.40 ±â€¯2.13 to 7.76 ±â€¯1.97 ng/(g mussel wet weight). Neither TNT nor 2-ADNT could be detected. Considering seasonal differences, orientation and distances of the moorings to the mine mound no correlation between levels in mussel tissue was evident.


Assuntos
Mytilus edulis/metabolismo , Trinitrotolueno/farmacocinética , Poluentes Químicos da Água/farmacocinética , Compostos de Anilina/farmacocinética , Animais , Ecotoxicologia/métodos , Substâncias Explosivas/metabolismo , Substâncias Explosivas/farmacocinética , Alemanha , Mytilus edulis/efeitos dos fármacos , Estações do Ano , Trinitrotolueno/análise , Trinitrotolueno/metabolismo , Poluentes Químicos da Água/metabolismo
8.
Neurocrit Care ; 29(1): 84-93, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29560598

RESUMO

BACKGROUND: Delayed cerebral ischemia (DCI) is the major cause of lethality and neuronal damage in patients who survived the primary subarachnoid hemorrhage (SAH). Asymmetric and symmetric dimethylarginines (ADMA and SDMA) inhibit nitric oxide production from L-arginine via distinct mechanisms. Elevated ADMA levels are associated with vasospasm after SAH. We aimed to study the time course of ADMA and SDMA in plasma and ventricular cerebrospinal fluid (CSF) and their associations with DCI and outcome. METHODS: We measured ADMA and SDMA in 34 SAH patients with an external ventricular drain at admission and on days 3, 6, 8, 12, and 15 and followed them up for clinical status and neurological outcome until 30 days post-discharge. DCI was defined as the appearance of new infarctions on cerebral computed tomography or magnetic resonance imaging. RESULTS: ADMA and SDMA plasma concentrations did not differ significantly at baseline between patients who suffered DCI (N = 14; 41%) and not; however, plasma ADMA reached a peak on days 8 and 15 after hemorrhage in patients with DCI (0.81-0.91 µmol/l). Baseline plasma L-arginine/ADMA ratio was significantly lower in patients with DCI (57.1 [34.3; 70.8] vs. 68.7 [55.7; 96.2]; p < 0.05). ADMA and SDMA concentrations in CSF were significantly higher in patients with DCI than without. In multivariable-adjusted linear regression models, CSF ADMA was negatively associated with the incidence of DCI (OR 0.03 [0.02-0.70]; p = 0.04), whereas CSF SDMA on the day of hemorrhage predicted poor neurological outcome until 30 days after discharge (OR 22.4 [1.21-416.02]; p = 0.04). CONCLUSIONS: Our study shows that ADMA and the L-arginine/ADMA ratio are associated with the incidence of DCI after SAH. By contrast, SDMA was associated with initial neuronal damage and poor neurological outcome after SAH. These data support the hypothesis that ADMA and L-arginine affect the pathophysiology of cerebral ischemia after SAH, while SDMA is a biomarker of neurological outcome after SAH.


Assuntos
Arginina/análogos & derivados , Arginina/sangue , Isquemia Encefálica/metabolismo , Avaliação de Resultados em Cuidados de Saúde , Hemorragia Subaracnóidea/metabolismo , Adulto , Idoso , Arginina/líquido cefalorraquidiano , Arginina/metabolismo , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/terapia , Angiografia Cerebral , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/terapia
9.
Toxicology ; 390: 117-123, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28899748

RESUMO

Since World War I considerable amounts of warfare material have been dumped at sea worldwide, but little is known about the fate of the explosive components in the marine environment. Sea dumped munitions are able to contaminate the surroundings because of the release of explosive chemicals due to corrosion and breaching or by detonation after blast-operations. This implies the risk of accumulation of toxic compounds in human and wildlife food chains. With the help of divers, we performed an active biomonitoring study with transplanted blue mussels (M. edulis) in a burdened area (Kolberger Heide, Germany) with explosive compounds near blast craters over an exposure time of 93days. With this biomonitoring system, we could show that blue mussels accumulate 2,4,6-trinitrotoluene (TNT) and its metabolites 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) in their tissues. In all mussels deployed at the ground, we found a body burden with 2-ADNT of 103.75±12.77ng/g wet weight and with 4-ADNT of 131.31±9.53ng/g wet weight. TNT itself has been found in six mussels with an average concentration of 31.04±3.26ng/g mussel wet weight. In the mussels positioned at one meter above the ground no TNT nor 2-ADNT could be detected, but 4-ADNT was found in all samples with an average concentration of 8.71±2.88ng/g mussel wet weight. To the best of our knowledge, this is the first study using blue mussels M. edulis as an active biomonitoring system for TNT and its metabolites 2-ADNT and 4-ADNT in a free field experiment in a burdened area. Moreover, with this system, we unequivocally proved that these toxic explosives accumulate in the marine biota resp. in the marine food chain, thereby posing a possible risk to the marine ecosphere and human health.


Assuntos
Monitoramento Ambiental/métodos , Mytilus edulis/metabolismo , Trinitrotolueno/metabolismo , Poluentes Químicos da Água/metabolismo , Poluição da Água , Compostos de Anilina/metabolismo , Animais , Biomarcadores/metabolismo , Biotransformação , Carga Corporal (Radioterapia) , Cadeia Alimentar , Contaminação de Alimentos , Alemanha , Humanos , Reprodutibilidade dos Testes , Medição de Risco
10.
Food Chem Toxicol ; 105: 486-497, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28458011

RESUMO

Arsenic trioxide (ATO) is highly efficient in treating acute promyelocytic leukemia. Other malignancies, however, are often less sensitive. Searching for compounds sensitizing arsenic resistant tumours for ATO the plant polyphenols, chrysin and silibinin, and the ATP binding cassette (ABC) transporter inhibitor MK-571, respectively, were investigated in human glioblastoma A-172 cells. The sensitivity of A-172 cells to ATO was characterized by a median cytotoxic concentration of 6 µM ATO. Subcytotoxic concentrations of chrysin, silibinin and MK-571, respectively, remarkably increased the sensitivity of the cells to ATO by factors of 4-6. Isobolographic analysis revealed synergistic interaction of the polyphenols and MK-571, respectively, with ATO. Sensitization by chrysin was associated with depletion of cellular glutathione and increased accumulation of arsenic. In contrast, silibinin and also MK-571 increased the accumulation of arsenic more strongly but without affecting the glutathione level. The increase of arsenic accumulation could be attributed to a decreased rate of arsenic export and, additionally, in the case of silibinin and MK-571, to an increasing amount of irreversibly accumulated arsenic. Direct interaction with ABC transporters stimulating export of glutathione and inhibiting export of arsenic, respectively, are discussed as likely mechanisms of the sensitizing activity of chrysin and silibinin.


Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Glioblastoma/tratamento farmacológico , Óxidos/toxicidade , Silimarina/farmacologia , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Arsenicais , Linhagem Celular Tumoral , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Silibina
11.
Mar Pollut Bull ; 111(1-2): 213-220, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27491368

RESUMO

Marine bivalves are known to ingest microplastics, but information on the consequences for their physiological performance is limited. To investigate a potential exposure pathway that has not yet been addressed, we mimicked the resuspension of microplastics from the sediment in a laboratory exposure experiment. For this, we exposed the Asian green mussel Perna viridis to 4 concentrations (0mg/l, 21.6mg/l, 216mg/l, 2160mg/l) of suspended polyvinylchloride (PVC) particles (1-50µm) for two 2-hour-time-periods per day. After 44days, mussel filtration and respiration rates as well as byssus production were found to be a negative function of particle concentration. Furthermore, within 91days of exposure, mussel survival declined with increasing PVC abundance. These negative effects presumably go back to prolonged periods of valve closure as a reaction to particle presence. We suggest that microplastics constitute a new seston component that exerts a stress comparable to natural suspended solids.


Assuntos
Perna (Organismo) , Cloreto de Polivinila , Poluentes Químicos da Água , Animais
12.
J Sci Food Agric ; 96(10): 3358-64, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26526345

RESUMO

BACKGROUND: Due to allergies or other health disorders a certain segment of the population is not able to safely consume some plant proteins, which are the main protein support in human nutrition. Coeliac disease is a prominent autoimmune disorder and requires a strict adherence to a gluten-free diet. The aim of this study was to identify suitable combinations of enzymatic hydrolysis and common unit operations in food processing (centrifugation, ultra-filtration) to produce gluten-free wheat gluten hydrolysates for food application. To analyse the hydrolysates, a simple and cheap competitive ELISA protocol was designed and validated in this study as well. RESULTS: The competitive ELISA was validated using gliadin spiked skim milk protein hydrolysates, due to the latter application of the assay. The limit of quantification was 4.19 mg kg(-1) , which allowed the identification of gluten-free (<20 mg kg(-1) ) hydrolysates. Enzymatic hydrolysis, including the type of peptidase, and the downstream processing greatly affected the antigenicity of the hydrolysates. CONCLUSION: Enzymatic hydrolysis and downstream processing operations, such as centrifugation and ultra-filtration, reduced the antigenicity of wheat gluten hydrolysates. Gluten-free hydrolysates were obtained with Flavourzyme after centrifugation (25 g L(-1) substrate) and after 1 kDa ultra-filtration (100 g L(-1) substrate). A multiple peptidase complex, such as Flavourzyme, seems to be required for the production of gluten-free hydrolysates. © 2015 Society of Chemical Industry.


Assuntos
Antígenos de Plantas/análise , Manipulação de Alimentos/métodos , Glutens/imunologia , Peptídeo Hidrolases/metabolismo , Triticum/química , Alérgenos/análise , Doença Celíaca/dietoterapia , Centrifugação , Dieta Livre de Glúten , Ensaio de Imunoadsorção Enzimática/métodos , Gliadina/análise , Glutens/química , Glutens/metabolismo , Humanos , Hidrólise , Proteínas de Plantas/imunologia , Ultrafiltração
13.
J Agric Food Chem ; 63(23): 5682-93, 2015 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-25996918

RESUMO

Flavourzyme is sold as a peptidase preparation from Aspergillus oryzae. The enzyme preparation is widely and diversely used for protein hydrolysis in industrial and research applications. However, detailed information about the composition of this mixture is still missing due to the complexity. The present study identified eight key enzymes by mass spectrometry and partially by activity staining on native polyacrylamide gels or gel zymography. The eight enzymes identified were two aminopeptidases, two dipeptidyl peptidases, three endopeptidases, and one α-amylase from the A. oryzae strain ATCC 42149/RIB 40 (yellow koji mold). Various specific marker substrates for these Flavourzyme enzymes were ascertained. An automated, time-saving nine-step protocol for the purification of all eight enzymes within 7 h was designed. Finally, the purified Flavourzyme enzymes were biochemically characterized with regard to pH and temperature profiles and molecular sizes.


Assuntos
Aspergillus oryzae/enzimologia , Endopeptidases/química , Endopeptidases/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Aspergillus oryzae/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Peso Molecular , Temperatura
14.
Mar Pollut Bull ; 96(1-2): 491-5, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26013589

RESUMO

Microplastics, which are accumulating in marine sediments, are assumed to pose a risk for deposit feeding invertebrates. We tested whether the fiddler crab Uca rapax ingests and retains microplastics in its body. Furthermore, we investigated whether retention rates depend on (a) the quality of the marine environment in which the plastics were pre-weathered and on (b) their abundance. For this, polystyrene pellets were submersed at a polluted and a pristine site near Niterói, Brazil, for 2 weeks. Then specimens of U. rapax were, in laboratory experiments, exposed to fragments (180-250 µm) derived from these pellets for 2 months. After this period, microplastics were observed in the gills, stomach and hepatopancreas of the animals. However, fragment retention was not influenced by the two factors that we manipulated. The presence of microplastics in different organs of the crab supports the assumption that these particles have the potential to harm marine invertebrates.


Assuntos
Braquiúros/metabolismo , Plásticos/metabolismo , Frutos do Mar , Poluentes Químicos da Água/metabolismo , Animais , Brasil , Meio Ambiente , Sedimentos Geológicos , Brânquias , Hepatopâncreas , Masculino , Poliestirenos/metabolismo , Estômago , Distribuição Tecidual
15.
J Agric Food Chem ; 61(36): 8641-9, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-23947566

RESUMO

Wheat gluten hydrolysis, used to generate seasonings, was studied using peptidases from Flammulina velutipes or commercial Flavourzyme. L-amino acids were added in a range from 0.5 to 75.0 mM, and L-isoleucine, L-leucine, L-valine, and L-phenylalanine were identified as the strongest inhibitors for both enzyme mixtures. L-serine inhibited Flammulina velutipes peptidases only, while L-histidine and L-glutamine inhibited Flavourzyme peptidases only. To reduce product inhibition by released L-amino acids, electrodialysis was explored. An increase of the degree of hydrolysis of up to 60% for Flammulina velutipes peptidases and 31% for Flavourzyme compared to that for the best control batch was observed after applying an electrodialysis unit equipped with an ultrafiltration membrane for two times 1 h during the 20 h of hydrolysis. The total transfer of free L-amino acids into the concentrate reached 25-30% per hour. Peptides passed the membrane less easily, although the nominal cutoff was 4 kDa.


Assuntos
Flammulina/enzimologia , Glutens/metabolismo , Peptídeo Hidrolases/metabolismo , Triticum/química , Aminoácidos/metabolismo , Aminoácidos/farmacologia , Diálise/métodos , Endopeptidases/metabolismo , Hidrólise , Inibidores de Proteases/farmacologia , Sementes/química
16.
Int J Qual Health Care ; 25(2): 176-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23360810

RESUMO

OBJECTIVE: Patient handover is an important element of continuity, quality and safety in patient care. Handover without standardized protocols is prone to information loss and might be a possible danger to patient safety. Checklists are established methods that help to structure complex processes in other high-risk fields such as aviation. In the past few years, their implementation has attracted research interest in medicine. We hypothesize that a checklist for handover between anaesthesiologist and post-anaesthesia care unit nurse will increase the amount of information transfer during patient handover after anaesthesia. DESIGN AND SETTING: A total of 120 post-anaesthesia patient handovers were recorded on video and analyzed. Forty handovers before the implementation of the checklist and 80 after the implementation of the checklist, randomized into two groups: with and without the use of the checklist. MAIN OUTCOME MEASURES: An overall number of items handed over, handover of specific items and duration of the handover were analyzed. RESULTS: With the use of the written checklist, the overall items handed over increased significantly from a median of 32.4-48.7%. The duration of handover increased from a median of 86-121 s. Instructions about items that should be included in handovers, but without the use of a written checklist, was not associated with an increase in the number of items handed over or duration of the interview. CONCLUSIONS: This study suggests that the use of a checklist for post-anaesthesia handover might improve the quality of patient handover by increasing the information handed over.


Assuntos
Período de Recuperação da Anestesia , Lista de Checagem/normas , Continuidade da Assistência ao Paciente/normas , Transferência da Responsabilidade pelo Paciente , Idoso , Idoso de 80 Anos ou mais , Humanos , Segurança do Paciente , Estudos Prospectivos , Gravação em Vídeo
17.
J Enzyme Inhib Med Chem ; 24(5): 1106-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19555187

RESUMO

The compounds pyrostatin A and B, isolated from Streptomyces sp. SA-3501 have been reported as N-acetyl-beta-D-glucosaminidase inhibitors with inhibition constants in the micromolar range. Recently, a comparison of NMR spectral data of the pyrostatins has led to a structural revision of the pyrostatins. It was shown that the pyrostatins A and B are identical to the ectoines 5-hydroxectoine and ectoine, respectively. Ectoines are known as compatible osmolytes in many halophilic and stress-tolerant bacteria. We have performed enzymatic experiments demonstrating that neither ectoine nor 5-hydroxyectoine exhibit an inhibitory effect on N-acetyl-beta-D-glucosaminidase. The previously reported inhibition of N-acetyl-beta-D-glucosaminidase by pyrostatins A and B may thus be due to the contamination of the compound preparations with a strong N-acetyl-beta-D-glucosaminidase inhibitor with an inhibition constant (Ki) in the nanomolar range, as has been reported in other Streptomyces species.


Assuntos
Ativação Enzimática/efeitos dos fármacos , Iminas/farmacologia , Pirrolidinas/farmacologia , Diamino Aminoácidos/química , Diamino Aminoácidos/farmacologia , Animais , Bovinos , Iminas/química , Rim/enzimologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pirrolidinas/química , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , beta-N-Acetil-Hexosaminidases/metabolismo
18.
J Am Soc Nephrol ; 20(2): 333-43, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19092119

RESUMO

Loss of a critical number of podocytes from the glomerular tuft leads to glomerulosclerosis. Even in health, some podocytes are lost into the urine. Because podocytes themselves cannot regenerate, we postulated that glomerular parietal epithelial cells (PECs), which proliferate throughout life and adjoin podocytes, may migrate to the glomerular tuft and differentiate into podocytes. Here, we describe transitional cells at the glomerular vascular stalk that exhibit features of both PECs and podocytes. Metabolic labeling in juvenile rats suggested that PECs migrate to become podocytes. To prove this, we generated triple-transgenic mice that allowed specific and irreversible labeling of PECs upon administration of doxycycline. PECs were followed in juvenile mice beginning from either postnatal day 5 or after nephrogenesis had ceased at postnatal day 10. In both cases, the number of genetically labeled cells increased over time. All genetically labeled cells coexpressed podocyte marker proteins. In conclusion, we demonstrate for the first time recruitment of podocytes from PECs in juvenile mice. Unraveling the mechanisms of PEC recruitment onto the glomerular tuft may lead to novel therapeutic approaches to renal injury.


Assuntos
Células Epiteliais/metabolismo , Glomérulos Renais/metabolismo , Podócitos/metabolismo , Animais , Apoptose , Movimento Celular , Feminino , Masculino , Células Mesangiais/metabolismo , Camundongos , Camundongos Transgênicos , Néfrons/metabolismo , Ratos , Ratos Sprague-Dawley , Células-Tronco/metabolismo
19.
J Cardiovasc Pharmacol ; 50(4): 367-71, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18049303

RESUMO

BACKGROUND: : Hypertension is a cardiovascular risk factor commonly associated with endothelial dysfunction and increased renal vascular resistance. Angiotensin receptor blockers (ARBs) may beneficially affect these parameters via antagonism of angiotensin type 1 (AT1) receptor-mediated vasoconstriction and vascular superoxide production. We therefore investigated whether the new ARB telmisartan improves endothelial function and renal vascular resistance in patients with essential hypertension. METHODS: : Thirty-seven patients with essential hypertension were randomized to receive telmisartan, the calcium channel blocker nisoldipine, or their combination for 6 weeks in a prospective, parallel group study. Brachial artery flow-mediated (endothelium-dependent) dilation (FMD) and renal vascular resistance index (RVRI) were evaluated using high-resolution ultrasound before, at 3 weeks (low dose), and at 6 weeks (high dose) after initiation of treatment. RESULTS: : At baseline, FMD and RVRI did not significantly differ between treatment groups. After 3 weeks of treatment neither treatment significantly changed FMD or RVRI. After 6 weeks of treatment, patients randomized to receive telmisartan alone or the combination, but not those treated with nisoldipine alone, displayed a significantly improved FMD, whereas RVRI values again were not significantly different as compared to those at baseline. CONCLUSION: : In our study cohort of patients with essential hypertension, treatment with telmisartan improved FMD but did not change RVRI. Future studies will demonstrate whether this telmisartan-induced effect may contribute to a blood pressure-independent reduction in cardiovascular morbidity.


Assuntos
Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Nisoldipino/farmacologia , Nisoldipino/uso terapêutico , Estudos Prospectivos , Método Simples-Cego , Telmisartan , Resultado do Tratamento , Resistência Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
20.
Stem Cells Dev ; 16(2): 329-38, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17521243

RESUMO

Recent studies have shown that in response to vascular damage or ischemia, bone marrow-derived endothelial progenitor cells (EPCs) are recruited into the circulation. To investigate whether antihypertensive treatment has an influence on the number of circulating EPCs, patients with essential hypertension were treated either with the angiotensin receptor antagonist telmisartan, the calcium channel blocker nisoldipine, or their combination for 6 weeks. At baseline and after 3 and 6 weeks of treatment, EPCs were identified and quantified by fluorescence-activated cell sorting (FACS) analysis and by their capacity to generate colony-forming units of the endothelial lineage (CFU-EC) in a methylcellulose-based assay. During treatment, patients in the nisoldipine groups, but not in the telmisartan group, showed a significant mobilization of EPCs, which in part had the capacity to generate large-sized colonies comprising more than 1,000 cells. Moreover, a remarkable correlation between the number of CFU-EC and the number of circulating CD133(+)/CD34(+)/CD146(+) cells was observed, thereby providing strong evidence that cells with this phenotype represent functional EPCs. No correlation was found between the numbers of CFU-EC and the blood pressure levels at any time point during the treatment. Hence, nisoldipine-induced mobilization of EPCs might represent a novel mechanism by which this antihypertensive compound independently of its blood pressure-lowering effect contributes to vasoprotection in patients with essential hypertension.


Assuntos
Anti-Hipertensivos/uso terapêutico , Células Endoteliais/fisiologia , Hipertensão/tratamento farmacológico , Células-Tronco/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Antígenos CD/metabolismo , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Pressão Sanguínea/fisiologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Células Endoteliais/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nisoldipino/uso terapêutico , Fenótipo , Células-Tronco/citologia , Telmisartan
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