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1.
Paediatr Anaesth ; 32(7): 815-824, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35332622

RESUMO

BACKGROUND: The validity of current tools for intraoperative objective assessment of nociception/antinociception balance during anesthesia in young and very young surgery children is unknown. AIM: Primary aim of the study was to test the hypothesis that the Newborn Infant Parasympathetic Evaluation (NIPE) index performs better in indicating nociception in anesthetized children below 2 years than changes in heart rate. Secondary aims were to evaluate associations between intraoperative changes in NIPE index values and postoperative pain and emergence delirium. METHODS: Fifty-one children aged <2 years who underwent surgery were included in this prospective observational study. Patients were assigned to either group 1 (healthy children, n = 31) or group 2 (critically ill, ventilated premature infants and neonates, n = 20). The NIPE index and heart rate in response to three defined nociceptive stimuli were continuously recorded. Two different scales, Kindliche Unbehagens- und Schmerzskala (KUS) and Pediatric Anesthesia Emergence Delirium (PAED) as well as a Pain Questionnaire were used to assess postoperative pain levels and emergence delirium. RESULTS: In total, 110 nociceptive events were evaluated. The analysis revealed a statistically significant association between a decrease in the NIPE index and all nociceptive stimuli, with a sensitivity of 92% and a specificity of 96%. The mean percentage decrease ranged from approx. 15%-30% and was highly statistically significant in both groups and for each of the nociceptive events except for venous puncture (p = .004). In contrast, no consistent change in heart rate was demonstrated. The KUS and PAED scale scores were significantly associated with the duration of anesthesia (p = .04), but not with intraoperative NIPE depression. CONCLUSION: The NIPE index was reliable for assessing intraoperative nociception in children aged <2 years and was more reproducible for detecting specific nociceptive stimuli during general anesthesia than heart rate. An effect on postoperative outcome is still elusive.


Assuntos
Delírio do Despertar , Nociceptividade , Anestesia Geral , Criança , Estado Terminal , Delírio do Despertar/diagnóstico , Frequência Cardíaca/fisiologia , Humanos , Lactente , Recém-Nascido , Medição da Dor , Dor Pós-Operatória
2.
Rev Sci Instrum ; 91(7): 074104, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752809

RESUMO

Principles of low pressure gas electron diffraction are introduced. An experimental setup has been constructed for measuring the electron diffraction patterns of gaseous samples at pressures below 10-3 mbar. Test measurements have been performed for benzoic acid at T = 287 K corresponding to a vapor pressure of the substance P = 2 × 10-4 mbar, for iodoform CHI3 at T = 288 K (P = 4 × 10-4 mbar), and for carbon tetraiodide CI4 at T = 290 K (P = 1 × 10-4 mbar). Due to the low experimental temperature, thermal decomposition of CI4 has been prevented, which was unavoidable in previous classical measurements at higher temperatures. From the obtained data, the molecular structures have been successfully refined. The most important semi-empirical equilibrium molecular parameters are re(Car-Car)av = 1.387(5) Å in benzoic acid, re(C-I) = 2.123(3) Å in iodoform, and re(C-I) = 2.133(7) Å in carbon tetraiodide. The determined parameters showed consistency with the theoretically predicted values. A critical comparison with the results of the earlier investigations has also been done.

3.
Rev Sci Instrum ; 91(7): 073103, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752877

RESUMO

We have designed and constructed a combined experimental setup for synchronous measurements of electron diffraction patterns and mass-spectra of gas samples. Test measurements have been performed for acetic acid at two temperatures, 296 K and 457 K. Electron diffraction data have been analyzed taking into account mass spectra measured in the same experiments. From the diffraction intensities, molecular structures and mole fractions of the acetic acid monomer and dimer have been refined. The obtained results demonstrate the importance of measuring mass spectra in gas electron diffraction experiments. In particular, it is possible to detect the sample decomposition, which can be used for the optimization of experimental conditions and for the data interpretation. The length of the hydrogen bond in the acetic acid dimer determined in this work, re(O⋯H) = 1.657(9) Å, is in good agreement with modern theoretical predictions. We recommend measuring the diffraction patterns of acetic acid for the calibration of the sample pressure in the diffraction volume.

4.
Arthritis Rheumatol ; 72(8): 1385-1395, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32182396

RESUMO

OBJECTIVE: Systemic sclerosis (SSc) is characterized by fibrosis, vascular disease, and inflammation. Adenosine signaling plays a central role in fibroblast activation. We undertook this study to evaluate the therapeutic effects of adenosine depletion with PEGylated adenosine deaminase (PEG-ADA) in preclinical models of SSc. METHODS: The effects of PEG-ADA on inflammation, vascular remodeling, and tissue fibrosis were analyzed in Fra-2 mice and in a B10.D2→BALB/c (H-2d ) model of sclerodermatous chronic graft-versus-host disease (GVHD). The effects of PEG-ADA were confirmed in vitro in a human full-thickness skin model. RESULTS: PEG-ADA effectively inhibited myofibroblast differentiation and reduced pulmonary fibrosis by 34.3% (with decreased collagen expression) (P = 0.0079; n = 6), dermal fibrosis by 51.8% (P = 0.0006; n = 6), and intestinal fibrosis by 17.7% (P = 0.0228; n = 6) in Fra-2 mice. Antifibrotic effects of PEG-ADA were also demonstrated in sclerodermatous chronic GVHD (reduced by 38.4%) (P = 0.0063; n = 8), and in a human full-thickness skin model. PEG-ADA treatment decreased inflammation and corrected the M2/Th2/group 2 innate lymphoid cell 2 bias. Moreover, PEG-ADA inhibited proliferation of pulmonary vascular smooth muscle cells (reduced by 40.5%) (P < 0.0001; n = 6), and prevented thickening of the vessel walls (reduced by 39.6%) (P = 0.0028; n = 6) and occlusions of pulmonary arteries (reduced by 63.9%) (P = 0.0147; n = 6). Treatment with PEG-ADA inhibited apoptosis of microvascular endothelial cells (reduced by 65.4%) (P = 0.0001; n = 6) and blunted the capillary rarefication (reduced by 32.5%) (P = 0.0199; n = 6). RNA sequencing demonstrated that treatment with PEG-ADA normalized multiple pathways related to fibrosis, vasculopathy, and inflammation in Fra-2 mice. CONCLUSION: Treatment with PEG-ADA ameliorates the 3 cardinal features of SSc in pharmacologically relevant and well-tolerated doses. These findings may have direct translational implications, as PEG-ADA has already been approved by the Food and Drug Administration for the treatment of patients with ADA-deficient severe combined immunodeficiency disease.


Assuntos
Adenosina Desaminase/farmacologia , Escleroderma Sistêmico/tratamento farmacológico , Pele/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Fibrose/tratamento farmacológico , Fibrose/imunologia , Fibrose/patologia , Antígeno 2 Relacionado a Fos/metabolismo , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Humanos , Imunidade Inata/efeitos dos fármacos , Inflamação , Camundongos , Camundongos Endogâmicos BALB C , Modelos Anatômicos , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/patologia , Escleroderma Sistêmico/imunologia , Escleroderma Sistêmico/patologia , Pele/efeitos dos fármacos , Pele/imunologia , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/imunologia , Doenças Vasculares/patologia
5.
Chemistry ; 25(9): 2313-2321, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30489662

RESUMO

Carbaboranes 1,2-(EH)2 -closo-1,2-C2 B10 H10 (E=S, Se) were prepared, in the case of E=Se for the first time. Their semi-experimental equilibrium molecular structures were established by the concerted use of quantum-chemical calculations and gas electron diffraction. A method was developed and implemented to quantify the contribution of experimental data to each refined structural parameter. The accuracy of the experimental structures and those calculated at the MP2 level of theory were gauged by comparison of experimental 11 B NMR chemical shifts with quantum-chemically computed values; the inclusion of electron correlation (GIAO-MP2) provided superior results. For the purpose of geometrical prediction, the remaining group 16 elements were considered, and the icosahedral structures for E=O and Te were also computed; for E=O the same theoretical approach was used as for E=S, and for E=Te a description similar to that for E=Se was employed.

6.
Cell Microbiol ; 20(2)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29156489

RESUMO

The human gastrointestinal tract is a complex ecosystem in which epithelial cells and microorganisms of the intestinal microbiota live in symbiosis. Certain members of the microbiota, in particular Escherichia coli strains of the B2 phylotype, carry the polyketide synthase-island encoding the genotoxin colibactin. Colibactin is a nonribosomal peptide or polyketide-nonribosomal peptide hybrid of still unsolved structure, which induces DNA double strand breaks (DSBs) in eukaryotic cells. However, direct contact between live bacteria and host cell is required in order to elicit these genotoxic effects. In this study, we used a variety of cell culture models, among them, a 3D cell culture approach based on decellularised small intestinal submucosa, to investigate whether the intestinal mucus layer has the potential to interfere with colibactin activity. We demonstrate that the expression of mucins and the formation of an adherent mucus layer significantly increased with increasing complexity of cell culture. Moreover, we show that the presence of an adherent mucus layer on epithelial cells attenuates the genotoxic activity of colibactin, by preventing the induction of DNA-DSBs. Removal of the adherent mucus layer restored the occurrence of DNA-DSBs.


Assuntos
Trato Gastrointestinal/microbiologia , Muco/microbiologia , Mutagênicos/metabolismo , Peptídeos/metabolismo , Policetídeos/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/fisiologia , Escherichia coli/patogenicidade , Microbioma Gastrointestinal/fisiologia , Ilhas Genômicas/fisiologia , Células HT29 , Humanos , Simbiose/fisiologia , Virulência/fisiologia
7.
BMC Cardiovasc Disord ; 16: 132, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27283399

RESUMO

BACKGROUND: Osteopontin (OPN) regulates the Ca(++)-deposition in bone and coronary arteries. Elevated OPN were also associated with (aortic) valve calcification in healthy individuals. This study aimed to investigate the association between OPN levels and mitral annulus calcification (MAC) in patients with coronary artery disease (CAD). METHODS: In this cross-sectional study OPN-levels were measured in 223 non-or ex-smoking patients (160 male, mean age: 61,09 ± 11,02 years; 63 female: mean age: 67,49 ± 7,87 years) with CAD. Plasma OPN levels were measured by ELISA and MAC was evaluated by echocardiography. RESULTS: Forward stepwise logistic regression analysis (likelihood quotient) showed significantly higher OPN-levels in patients with MAC compared to patient without calcified mitral annulus independent from the classic risk factors age and severity of coronary artery disease (CAD). In addition to age and the severity of CAD, the circulating OPN amount was a significant predictor for MAC. CONCLUSIONS: This is the first clinical trial which observed increased circulating OPN levels in MAC, suggesting a distinct role of OPN in the process of MAC. Considering the current knowledge about OPN it is more likely that OPN does not promote but counteracts valve calcification and therefore is elevated in course of a calcification processes.


Assuntos
Calcinose/sangue , Doença da Artéria Coronariana/sangue , Estenose Coronária/sangue , Doenças das Valvas Cardíacas/sangue , Osteopontina/sangue , Idoso , Biomarcadores/sangue , Calcinose/diagnóstico por imagem , Estudos de Casos e Controles , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Estudos Transversais , Ecocardiografia , Ensaio de Imunoadsorção Enzimática , Feminino , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença , Regulação para Cima
8.
J Phys Chem A ; 120(15): 2420-30, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27023801

RESUMO

The coexistence of two conformers in perfluoropropanoyl fluoride, CF3CF2C(O)F, differing in the CC-CF dihedral angle (gauche 85(10)% and anti 15(10)%), has been determined by means of gas-phase electron diffraction (GED). Quantum-chemical calculations performed at the MP2 and B3LYP approximations and cc-pVTZ basis sets reproduce the experimental values with confidence. By contrast, FTIR spectra give no clear evidence for the anti-conformer in the gas phase. Information on this less abundant but stable rotamer is obtained from matrix-isolation/FTIR spectroscopy and liquid Raman spectroscopy. In situ crystallization and single-crystal X-ray diffraction (XRD) data reveal the presence of solely the gauche-conformation in the solid state. A set of intermolecular interactions including C═O···C═O, C-F···F-C, and F···C═O is detected. The nature of bonding and the relative stabilities of gauche- and anti-conformers are explored using natural bond orbitals.

9.
Phys Chem Chem Phys ; 18(1): 393-402, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26617390

RESUMO

The molecular structure and conformational properties of 2,2,2-trichloroethyl chloroformate, ClC(O)OCH2CCl3 were determined experimentally using gas-phase electron diffraction (GED) and theoretically based on quantum-chemical calculations at the MP2 and DFT levels of theory. Further experimental measurements such as UV-visible, IR and Raman spectroscopy were complemented with the corresponding theoretical studies. All experimental results and calculations confirm the presence of two conformers namely anti-gauche (C1 symmetry) and anti-anti (Cs symmetry). The conformational preference was rationalised by NBO and AIM analyses. Molecular properties such as ionisation potential, electronegativity, chemical potential, chemical hardness and softness were deduced from HOMO-LUMO analyses. The TD-DFT approach was applied to assign the electronic transitions observed in the UV-visible spectrum. A detailed interpretation of the infrared and Raman spectra of the title compound are reported. Using calculated frequencies as a guide, IR and Raman spectra also provide evidence for the presence of both C1 and Cs conformers.

10.
Dalton Trans ; 41(13): 3630-2, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22089403

RESUMO

The first gas phase structure of a silanetriol, tert-butylsilane-triol [(t)BuSi(OH)(3)], determined by gas electron diffraction (GED), is reported. Quantum chemical calculations have been performed to elucidate potential intermolecular interactions between silanetriol molecules in the gas phase. The results are set into contrast to solid state structures of (t)BuSi(OH)(3) and related compounds.

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