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1.
Appl Opt ; 62(18): 4949-4957, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37707273

RESUMO

Endoscopic optical diagnostics for IC engines offer the advantage of retaining the full operating range and thermal properties of the production engine. The custom-designed modular hybrid UV endoscope system is optimized for application in IC engines.; however, its hybrid refractive/diffractive relay element is expensive and has a narrow operating wavelength range. To make the endoscopic imaging more universally applicable, the hybrid relay element of the mentioned endoscope system was replaced by commercial UV camera lenses, and several combinations were characterized in terms of resolution, brightness, and chromatic aberration. With an unintensified CCD camera, endoscope systems using commercial camera lenses had better resolution at investigated magnifications of 0.5 and 1. However, with an intensified camera, the system with the hybrid relay lens had the best overall performance in its design wavelength range. Selected imaging systems were used in a spark-ignition engine to image O H ∗-chemiluminescence, with results consistent with those from bench-top characterization.

2.
Psychol Med ; 49(16): 2772-2780, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30606279

RESUMO

BACKGROUND: Studies investigating the underlying mechanisms of hallucinations in patients with schizophrenia suggest that an imbalance in top-down expectations v. bottom-up processing underlies these errors in perception. This study evaluates this hypothesis by testing if individuals drawn from the general population who have had auditory hallucinations (AH) have more misperceptions in auditory language perception than those who have never hallucinated. METHODS: We used an online survey to determine the presence of hallucinations. Participants filled out the Questionnaire for Psychotic Experiences and participated in an auditory verbal recognition task to assess both correct perceptions (hits) and misperceptions (false alarms). A hearing test was performed to screen for hearing problems. RESULTS: A total of 5115 individuals from the general Dutch population participated in this study. Participants who reported AH in the week preceding the test had a higher false alarm rate in their auditory perception compared with those without such (recent) experiences. The more recent the AH were experienced, the more mistakes participants made. While the presence of verbal AH (AVH) was predictive for false alarm rate in auditory language perception, the presence of non-verbal or visual hallucinations were not. CONCLUSIONS: The presence of AVH predicted false alarm rate in auditory language perception, whereas the presence of non-verbal auditory or visual hallucinations was not, suggesting that enhanced top-down processing does not transfer across modalities. More false alarms were observed in participants who reported more recent AVHs. This is in line with models of enhanced influence of top-down expectations in persons who hallucinate.


Assuntos
Alucinações/diagnóstico , Alucinações/psicologia , Idioma , Semântica , Percepção da Fala , Estimulação Acústica/métodos , Adulto , Análise de Variância , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Distorção da Percepção , Inquéritos e Questionários , Adulto Jovem
3.
J Chromatogr A ; 1574: 122-129, 2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30190080

RESUMO

A gas chromatographic method for the determination of volatile contaminants (halogenated solvents, benzene, toluene, ethyl-benzene, xylenes, styrene) and phenol in e-liquids was developed and validated with a working range of 0.01 (limit of quantification) to 0.5 mg/l, and variation coefficients between 2 and 14%. Selectivity performing MS/MS-detection was sufficient for all analytes except for phenol: e-liquids contain high amounts of aroma compounds in excess of 105 compared to phenol. A number of these compounds potentially interfere at the retention time of phenol, showing all masses (including daughter ions and transitions) of phenol. To allow the detection of phenol in this matrix, a novel approach of adding a polar molecule to the injection solvent was used, modulating the polarity of the column, and thus the retention time of phenol. By adding 3 µl/ml and 10 µl/ml of 1,2-propanediol the retention time of phenol was shifted by 0.06 and 0.11 min respectively, while interfering peaks have not been shifted. This allowed a reliable confirmation of the presence of phenol. The introduced approach is an easy way to generate an additional chromatographic dimension for confirmation purposes, not requiring additional equipment.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Gasosa , Fenol/análise , Solventes/química , Fenol/química , Espectrometria de Massas em Tandem , Fatores de Tempo
4.
HIV Med ; 19(6): 376-385, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29441669

RESUMO

OBJECTIVES: The aim of the study was to investigate the hypothesis of accelerated cognitive ageing in HIV-positive individuals using longitudinal assessment of cognitive performance and quantitative magnetic resonance imaging (MRI). METHODS: We assessed a broad cognitive battery and quantitative MRI metrics [voxel-based morphometry (VBM) and diffusion tensor imaging (DTI)] in asymptomatic HIV-positive men who have sex with men (15 aged 20-40 years and 15 aged ≥ 50 years), and HIV-seronegative matched controls (nine aged 20-40 years and 16 aged ≥ 50 years). RESULTS: Being HIV positive was associated with greater decreases in executive function and global cognition. Additionally, using DTI, we found that the HIV-positive group had a greater increase in mean diffusivity, but we did not find group differences in volume change using VBM. With respect to the HIV status by age group interaction, this was statistically significant for change in global cognition, with older HIV-positive individuals showing greater global cognitive decline, but there were no significant interaction effects on other measures. Lastly, change in cognitive performance was correlated with change in the DTI measures, and this effect was stronger for the HIV-positive participants. CONCLUSIONS: In the present study, we found some evidence for accelerated ageing in HIV-positive individuals, with a statistically significant HIV status by age group interaction in global cognition, although this interaction could not be explained by the imaging findings. Moreover, we also found that change in cognitive performance was correlated with change in the DTI measures, and this effect was stronger for the HIV-positive participants. This will need replication in larger studies using a similarly lengthy follow-up period.


Assuntos
Envelhecimento/patologia , Disfunção Cognitiva/fisiopatologia , Infecções por HIV/fisiopatologia , Infecções por HIV/psicologia , Imageamento por Ressonância Magnética , Neuroimagem , Adulto , Envelhecimento/imunologia , Cognição , Disfunção Cognitiva/virologia , Seguimentos , Infecções por HIV/imunologia , Homossexualidade Masculina , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Tempo , Adulto Jovem
8.
Artigo em Alemão | MEDLINE | ID: mdl-23455560

RESUMO

"Dynamic", "complexity", and "diversity" are terms that best describe the challenges in the workplace resulting from the changing nature of work. These changes should conform to the criteria of human-related work design. However, the number of pensions for reduced earning capacity and the number of unfit for work days caused by psychic disorders are rising. Affective disorders, including depression, are the largest group. Depression represents a long-term consequence of work demands. Empirical results confirm a significant relationship between depression and the objective existing as well as the subjective perceived workload conditions. Burn-out as a further long-term consequence depends inter alia on the design of the physical work demands, the environmental conditions, the psychosocial conditions, and the transparency of the decision and information processes in a company. Additionally, empirical results show that the short-term consequences of work demands, i.e., fatigue, satiation, and monotony correlate with the burn-out components of exhaustion and alienation from work. Furthermore, using restructuring as an example, it is demonstrated that the changes in work that accompany modifications in the working world also have other health-related consequences.


Assuntos
Nível de Saúde , Transtornos Mentais/epidemiologia , Doenças Profissionais/epidemiologia , Desemprego/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Emprego , Alemanha/epidemiologia , Humanos , Prevalência , Psicologia , Desemprego/tendências , Local de Trabalho
9.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): m1208-9, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969493

RESUMO

The title compound, [Re(4)(µ(3)-OH)(4)(CO)(12)]·4C(5)H(5)N, crystallizes with one tetranuclear rhenium(I) cubane-like molecule and four pyridine mol-ecules in the asymmetric unit. The coordination environment of each Re(I) atom is distorted octahedral. Four intra-molecular O-H⋯N and four inter-molecular C-H⋯O hydrogen-bond inter-actions are observed. Relatively strong hydrogen bonds are found between the hydrogen-bond donor (µ(3)-OH) and acceptor (basic N atom of pyridine), with N⋯O distances between 2.586 (10) and 2.628 (10) Å. Inter-cube distances of 9.873 (2) and 12.376 (3) Šare observed.

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o777, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412651

RESUMO

In the title compound, C(15)H(11)NO(2), two C-H⋯O hydrogen bonds are observed in the crystal structure, as well as π-π stacking with a centroid-centroid distance of 3.623 (2) Å. The planarity of the two ring systems is illustrated by very small deviations of all the atoms from these planes [largest deviations = 0.003 (3) and 0.010 (3) Šfor the phenyl and fused-benzene rings, respectively]. The dihedral angle between these two planes is 77.65 (9)°.

11.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o914, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412758

RESUMO

In the crystal of the title hydrated molecular salt, C(6)H(10)N(2) (2+)·SO(4) (2-)·H(2)O, N-H⋯O and O-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the ab plane. C-H⋯O hydrogen bonds are observed both within these layers and between mol-ecules and ions in adjacent layers.

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 12): o3472, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23476281

RESUMO

THE TITLE COMPOUND [SYSTEMATIC NAME: 5-(trifluoro-meth-oxy)-1H-indole-2,3-dione], C9H4F3NO3, crystallized with two mol-ecules in the asymmetric unit. Inter-molecular N-H⋯O hydrogen bonds link the mol-ecules to form layers parallel to the ab plane. In addition, π-π stacking inter-actions are observed with a centroid-centroid distance of 3.721 (1) Å. The near planarity of the two isatin ring systems is illustrated by by the maximum deviations of 0.023 (1) and 0.025 (1) Šfor the N atom in each case.

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): m1359-60, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284342

RESUMO

In the title compound, [Re(2)(CH(3)O)(2)(CO)(6)(C(4)H(6)N(3)O)], the two Re(I) atoms are linked by a methoxo and methanolato bridge, as well as by a creatinine ligand that coordinates in a bidentate fashion. Three fac-carbonyl ligands occupy the rest of the slightly distorted octa-hedral geometry around each Re(I) atom. The bridging methanolato and methoxo ligands are bent out of the Re(2)O(2) plane by 49.2 (4) and 47.8 (3)° respectively. This is normally associated with a methanolato-bridging-type coordination rather that the more planar methoxo-type bridging. Furthermore, the creatinine bridging molecule is very slightly distorted from the Re(2)N(2)C plane, indicating that the pyrazolo N atom bonded to the Rh(I) atom is not protonated. Charge balance can thus only be attained if one assumes a positional disorder for the methanolato/methoxo H atom. All attempts to locate disordered protons around these O atoms were unsuccessful. Four hydrogen bonds, one N-H⋯O and three C-H⋯O, are observed in the structure. The mol-ecules pack in a head-to-head and tail-to-tail fashion when viewed along the c axis, in alternating columns.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3235-6, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284535

RESUMO

The title compound, C(10)H(15)NO(2), crystallized with three mol-ecules in the asymmetric unit. These three mol-ecules are quite similar except for slight differences in the torsion angles of the substituents on the ring. The isopropyl C-C-N-C torsion angles (towards the carbon next to the ethyl bound carbon), for example, are -150.63 (11), -126.77 (13) and -138.76 (11)° for mol-ecules A, B and C, respectively, and the C-C-C-N torsion angles involving the ethyl C atoms are 102.90 (13), 87.81 (14) and 86.47 (13)°. The main difference between the three mol-ecules lies in the way they are arranged in the solid-state structure. All three mol-ecules form dimers that are connected through strong O-H⋯O hydrogen bonds with R(2) (2)(10) graph-set motifs. The symmetry of the dimers formed does however differ between mol-ecules. Mol-ecules B connect with each other to form inversion dimers. Mol-ecules A and C, on the other hand, form dimers with local twofold symmetry, but the two mol-ecules are crystallographically distinct. The B and C molecules are linked to themselves and to each other via C-H⋯O hydrogen bonds. This results in the formation of a three-dimensional network structure.

15.
Toxicology ; 290(1): 50-8, 2011 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-21871943

RESUMO

The application of toxicogenomics as a predictive tool for chemical risk assessment has been under evaluation by the toxicology community for more than a decade. However, it predominately remains a tool for investigative research rather than for regulatory risk assessment. In this study, we assessed whether the current generation of microarray technology in combination with an in vitro experimental design was capable of generating robust, reproducible data of sufficient quality to show promise as a tool for regulatory risk assessment. To this end, we designed a prospective collaborative study to determine the level of inter- and intra-laboratory reproducibility between three independent laboratories. All test centres (TCs) adopted the same protocols for all aspects of the toxicogenomic experiment including cell culture, chemical exposure, RNA extraction, microarray data generation and analysis. As a case study, the genotoxic carcinogen benzo[a]pyrene (B[a]P) and the human hepatoma cell line HepG2 were used to generate three comparable toxicogenomic data sets. High levels of technical reproducibility were demonstrated using a widely employed gene expression microarray platform. While differences at the global transcriptome level were observed between the TCs, a common subset of B[a]P responsive genes (n=400 gene probes) was identified at all TCs which included many genes previously reported in the literature as B[a]P responsive. These data show promise that the current generation of microarray technology, in combination with a standard in vitro experimental design, can produce robust data that can be generated reproducibly in independent laboratories. Future work will need to determine whether such reproducible in vitro model(s) can be predictive for a range of toxic chemicals with different mechanisms of action and thus be considered as part of future testing regimes for regulatory risk assessment.


Assuntos
Bases de Dados Genéticas/normas , Laboratórios/normas , Projetos de Pesquisa/normas , Toxicogenética/normas , Células Hep G2 , Humanos , Análise de Componente Principal/métodos , Análise de Componente Principal/normas , Estudos Prospectivos , Análise Serial de Proteínas/métodos , Análise Serial de Proteínas/normas , Reprodutibilidade dos Testes , Toxicogenética/métodos
16.
Oncogene ; 29(16): 2415-26, 2010 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20140020

RESUMO

The p53 tumor suppressor protein is frequently mutated in human tumors. It is thought that the p53 pathway is indirectly impaired in the remaining tumors, for example by overexpression of its important regulators Mdm2 and Mdm4, making them attractive targets for the development of anti-cancer agents. Recent studies have suggested that Mdm4 levels determine the sensitivity of tumor cells for anti-cancer therapy. To investigate this possibility, we studied the drug sensitivity of several breast cancer cell lines containing wild-type p53, but expressing different Mdm4 levels. We show that endogenous Mdm4 levels can affect the sensitivity of breast cancer cells to anti-cancer agents, but in a cell line-dependent manner and depending on an intact apoptotic response. Furthermore, treatment with the non-genotoxic agent Nutlin-3 sensitizes cells for doxorubicin, showing that activation of p53 by targeting its regulators is an efficient strategy to decrease cell viability of breast cancer cells. These results confirm a function of Mdm4 in determining the efficacy of chemotherapeutic agents to induce apoptosis of cancer cells in a p53-dependent manner, although additional undetermined factors also influence the drug response. Targeting Mdm4 to sensitize tumor cells for chemotherapeutic drugs might be a strategy to effectively treat tumors harboring wild-type p53.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proteínas Nucleares/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Imidazóis/farmacologia , Proteínas Nucleares/análise , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas/análise , Proteína Supressora de Tumor p53/fisiologia
17.
Neth Heart J ; 17(10): 378-84, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19949647

RESUMO

Purpose. Therapeutic mild hypothermia (TMH) is indicated for comatose survivors of an out-ofhospital cardiac arrest (OHCA) to improve general outcome. Although widely used, there are not many reports on its use on a critical care unit (CCU) or on the comparison of cooling methods.Methods. In a retrospective analysis covering January 2005 to December 2006, 75 consecutive comatose subjects post-OHCA due to ventricular fibrillation and nonventricular fibrillation rhythms (asystole/pulseless electrical activity) were studied in a single tertiary PCI centre. Subjects treated with conventional post-resuscitation care without TMH served as controls (n=26; Jan 2005-Sep 2005). Outcome from controls at hospital discharge was compared with subjects treated with TMH (n=49; Oct 2005-Dec 2006). During the study period, TMH was induced by either external (n=25; Oct 2005-Feb 2006) or endovascular (n=24; Mar 2006-Dec 2006) approach.Results. Besides more females in the control group, there were no major differences in baseline characteristics present between all groups. TMH improved survival (OR 0.36 [0.13-0.95], p<0.05) and neurological outcome (OR 0.23 [0.07-0.70], p<0.01). After subanalysis, TMH-improved outcome did not differ between the two cooling methods used. However, the times to reach TMH and normothermia were shorter with the endovascular approach.Conclusion. TMH induced on a CCU improves survival and neurological outcome after post-OHCA coma. TMH by endovascular approach was more feasible compared with external cooling, but the two cooling methods did not result in a different outcome. (Neth Heart J 2009;17:378-84.).

18.
Ophthalmologe ; 106(9): 839-44, 2009 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-19697042

RESUMO

BACKGROUND: This investigation analyzed the possibility to provide information about the medical qualities of ophthalmologists to make it easier for patients to find the right physician in a Pareto optimal way, i.e. to supply information so that nobody is harmed and at least one derives benefits. METHODS: Extensive interviews with key deciders in the system for ophthalmological care were carried out and analyzed. RESULTS: Pareto optimization is possible. However, implementation is not yet feasible mainly because of legal and economic restrictions and because of difficulties of the measuring system. In order to come to a result, a major medical, economic and legal effort would be required which is unlikely to come into place in the short-term. CONCLUSION: At least in the near future there will be no new Pareto optimal information systems available for patients in order to find the appropriate ophthalmologist. In the mid-term the situation could change if the open questions can be resolved.


Assuntos
Comunicação , Informação de Saúde ao Consumidor/métodos , Disseminação de Informação/métodos , Oftalmologia/métodos , Educação de Pacientes como Assunto/métodos , Relações Médico-Paciente , Alemanha
19.
Invest New Drugs ; 27(2): 166-72, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18696011

RESUMO

The purpose of this study was to evaluate the efficacy (progression free survival (PFS) and response rate) and safety of vinorelbine and trastuzumab combination chemotherapy in patients with HER2-overexpressing, metastatic breast cancer as a first line chemotherapy regimen. Patients with histologically confirmed, HER2-positive (immunohistochemistry (ICH) 3+, or 2+ and FISH+) metastatic breast cancer who had nor received prior vinorelbine or anti-HER2 therapy in the adjuvant setting, received at least eight weeks of vinorelbine i.v. (25 mg/g weekly) and trastuzumab (4 mg/kg on day 1 followed by 2 mg/kg weekly). Forty-one women from six participating centers were enrolled into the trial. The overall response rate, was 43.9% (18 of 41 patients), (CI 28-60.3%), 30% of patients were progression free after 1 year. Four patients reached complete remission, 14 partial remission and five had stable disease for at least 18 weeks. Six patients developed primary progression. 35 patients (85%) experienced progression after a median time of 235 days. Therapy was in general well-tolerated. There were two CTC grade 4 infusion syndromes and two patients experienced cardiotoxicity at least grade 2. This phase II trial of vinorelbine and trastuzumab demonstrated an effective and well-tolerated regimen with a favourable safety profile.


Assuntos
Adenocarcinoma/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Genes erbB-2 , Vimblastina/análogos & derivados , Adenocarcinoma/patologia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Metástase Neoplásica , Trastuzumab , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos , Vinorelbina
20.
Crit Rev Oncol Hematol ; 64(1): 64-72, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17317205

RESUMO

This randomized phase 2 study explored the feasibility of delivering four to six cycles of the dose-intensified regimen FEC-100 (5-fluorouracil, epirubicin, and cyclophosphamide) to elderly patients with stage II-III breast cancer, using pegfilgrastim for neutrophil support. Sixty patients aged 65-77 years received single 6mg doses of pegfilgrastim on day 2 of FEC-100, either as primary prophylaxis (all cycles: PP), or as secondary prophylaxis (all cycles following a neutropenic event: SP). Neutropenic events (a composite endpoint that included grade 3 neutropenia+fever, grade 4 neutropenia, infectious complication requiring systemic anti-infectives and chemotherapy dose delay/reduction) occurred in 24/30 (80%) of the PP and 21/29 (72%) of the SP group in the first cycle. Most patients received all chemotherapy cycles at full dose on schedule (26/30 [87%] PP; 20/29 [69%] SP). These data indicate that delivery of FEC-100 is feasible with pegfilgrastim support in elderly breast cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Neutropenia/prevenção & controle , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Neoplasias da Mama/complicações , Ciclofosfamida/administração & dosagem , Ciclofosfamida/toxicidade , Epirubicina/administração & dosagem , Epirubicina/toxicidade , Feminino , Filgrastim , Fluoruracila/administração & dosagem , Fluoruracila/toxicidade , Fator Estimulador de Colônias de Granulócitos/toxicidade , Humanos , Neutropenia/induzido quimicamente , Infecções Oportunistas/induzido quimicamente , Polietilenoglicóis , Pré-Medicação , Proteínas Recombinantes , Resultado do Tratamento
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