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[PMID]:29305456
[Au] Autor:Sprague S; Petrisor B; Jeray K; McKay P; Heels-Ansdell D; Schemitsch E; Liew S; Guyatt G; Walter SD; Bhandari M; FLOW Investigators
[Ad] Endereço:McMaster University, 293 Wellington Street North, Suite 110, Hamilton, Ontario L8L 8E7, Canada.
[Ti] Título:Wound irrigation does not affect health-related quality of life after open fractures: results of a randomized controlled trial.
[So] Source:Bone Joint J;100-B(1):88-94, 2018 01.
[Is] ISSN:2049-4408
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:AIMS: The Fluid Lavage in Open Fracture Wounds (FLOW) trial was a multicentre, blinded, randomized controlled trial that used a 2 × 3 factorial design to evaluate the effect of irrigation solution (soap normal saline) and irrigation pressure (very low low high) on health-related quality of life (HRQL) in patients with open fractures. In this study, we used this dataset to ascertain whether these factors affect whether HRQL returns to pre-injury levels at 12-months post-injury. PATIENTS AND METHODS: Participants completed the Short Form-12 (SF-12) and the EuroQol-5 Dimensions (EQ-5D) at baseline (pre-injury recall), at two and six weeks, and at three, six, nine and 12-months post-fracture. We calculated the Physical Component Score (PCS) and the Mental Component Score (MCS) of the SF-12 and the EQ-5D utility score, conducted an analysis using a multi-level generalized linear model, and compared differences between the baseline and 12-month scores. RESULTS: We found no clinically important differences between irrigating solutions or pressures for the SF-12 PCS, SF-12 MCS and EQ-5D. Irrespective of treatment, participants had not returned to their pre-injury function at 12-months for any of the three outcomes (p < 0.001). CONCLUSION: Neither the composition of the irrigation solution nor irrigation pressure applied had an effect on HRQL. Irrespective of treatment, patients had not returned to their pre-injury HRQL at 12 months post-fracture. Cite this article: 2018;100-B:88-94.
[Mh] Termos MeSH primário: Fraturas Expostas/terapia
Qualidade de Vida
Irrigação Terapêutica/métodos
[Mh] Termos MeSH secundário: Adulto
Idoso
Feminino
Seguimentos
Fixação Interna de Fraturas/métodos
Fraturas Expostas/reabilitação
Seres Humanos
Masculino
Meia-Idade
Pressão
Psicometria
Sabões/administração & dosagem
Cloreto de Sódio/administração & dosagem
[Pt] Tipo de publicação:JOURNAL ARTICLE; MULTICENTER STUDY; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Soaps); 451W47IQ8X (Sodium Chloride)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180107
[St] Status:MEDLINE
[do] DOI:10.1302/0301-620X.100B1.BJJ-2017-0955.R1


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[PMID]:29358740
[Au] Autor:Furukawa T; Kobashi K; Kurosaki Y; Miyagawa K; Kanoda K
[Ad] Endereço:Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. tetsuya.furukawa@rs.tus.ac.jp.
[Ti] Título:Quasi-continuous transition from a Fermi liquid to a spin liquid in κ-(ET) Cu (CN) .
[So] Source:Nat Commun;9(1):307, 2018 01 22.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The Mott metal-insulator transition-a manifestation of Coulomb interactions among electrons-is known as a discontinuous transition. Recent theoretical studies, however, suggest that the transition is continuous if the Mott insulator carries a spin liquid with a spinon Fermi surface. Here, we demonstrate the case of a quasi-continuous Mott transition from a Fermi liquid to a spin liquid in an organic triangular-lattice system κ-(ET) Cu (CN) . Transport experiments performed under fine pressure tuning have found that as the Mott transition is approached, the Fermi liquid coherence temperature continuously falls to the scale of kelvins, with a divergent quasi-particle decay rate on the metal side, and the charge gap continuously closes on the insulator side. A Clausius-Clapeyron analysis provides thermodynamic evidence for the extremely weak first-order nature of the transition. These results provide additional support for the existence of a spinon Fermi surface, which becomes an electron Fermi surface when charges are delocalized.
[Mh] Termos MeSH primário: Metais/química
Compostos Organometálicos/química
Temperatura Ambiente
Termodinâmica
[Mh] Termos MeSH secundário: Modelos Teóricos
Pressão
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Metals); 0 (Organometallic Compounds)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180124
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02679-7


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[PMID]:28460771
[Au] Autor:Raizada A; Gedela M; Shaikh KA; Apte N; DeHaan M; Stanton C
[Ad] Endereço:Cardiovascular Disease Fellow, Sanford Heart Hospital, University of South Dakota Sanford School of Medicine, Sioux Falls, SD, United States.
[Ti] Título:Pressure-Guided cryoablation of pulmonary veins in atrial fibrillation: A fast and effective strategy.
[So] Source:Indian Heart J;69(2):223-225, 2017 Mar - Apr.
[Is] ISSN:0019-4832
[Cp] País de publicação:India
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Cryoballoon ablation of atrial fibrillation (AF) involves successful electrical pulmonary vein isolation (PVI). Pulmonary vein (PV) ostial occlusion with cryoballoon is classically assessed using PV angiography. A pressure-guided technique to assess ostial occlusion has been evaluated in small cohorts with mixed results. We evaluated the efficacy of this pressure-guided PVI technique and its impact on reducing contrast and fluoroscopy time as compared to the traditional approach. METHODS: We evaluated patients with paroxysmal AF, who underwent cryoballoon PVI. Patients prior to January 20th, 2013 underwent confirmation of PV occlusion by angiography only. Patients ablated after this time had PV occlusion initially determined by pressure monitoring and further confirmed by contrast injection into the PV in most cases (Pressure-guided PVI). Differences in the volume of contrast used and fluoroscopy time were evaluated. RESULTS: 46 patients had pressure-guided PVI and29 patients had occlusion of PV confirmed by angiography alone. Pressure-guided PVI was 99.5% successful in ablating AF, which was non-inferior to traditional method of PV isolation. This technique used an average of 8cc of contrast and 21.5min of fluoroscopy time, which was significantly less than the contrast amount used, and fluoroscopy time with angiographic isolation of PV. CONCLUSION: Pressure-guided PVI is an effective method for cryoablation of AF. This method not only significantly reduces the volume of contrast used but also decreases the fluoroscopy without compromising the success of PVI.
[Mh] Termos MeSH primário: Fibrilação Atrial/cirurgia
Criocirurgia/normas
Sistema de Condução Cardíaco/cirurgia
Guias de Prática Clínica como Assunto
Veias Pulmonares/cirurgia
[Mh] Termos MeSH secundário: Fibrilação Atrial/fisiopatologia
Criocirurgia/métodos
Feminino
Sistema de Condução Cardíaco/fisiopatologia
Frequência Cardíaca/fisiologia
Seres Humanos
Masculino
Meia-Idade
Duração da Cirurgia
Pressão
Estudos Retrospectivos
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE


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[PMID]:29465580
[Au] Autor:Höhne S; Hesse V
[Ti] Título:Standard values for gas-perfusion manometry of the esophagus.
[So] Source:Medicine (Baltimore);97(8):e9910, 2018 Feb.
[Is] ISSN:1536-5964
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The manometry with water-perfused or solid-state catheters is the predominant diagnostic procedure to detect motility disorders of the esophagus. Another method is the manometry using gas-perfused catheters. Although the high-resolution manometry is the method of first choice, the conventional manometry with helium has some advantages: the simple and hygienically unproblematic use and the absence of any artefacts by the perfusion medium compared with water-perfusion, and the considerably lower costs compared with the solid-state catheters. Every method has own normal values because of the specific pressure transmission and the design of the catheter probes. To our knowledge, normal values for gas-perfusion manometry of the esophagus have not yet been published.The esophageal manometry with helium-perfused catheters was performed in 30 healthy volunteers. The main parameters of the esophageal motility and the lower esophageal sphincter were analyzed by liquid and bolus-like swallows and compared with the previous published values in other manometric procedures.The values of the motility in the distal esophagus are consistent; the pressure of the lower esophageal sphincter is generally lower than with other methods. The distal wave amplitude and the propagation velocity are significant higher in the distal esophagus than in the middle. The perfusion medium is well tolerated by the investigated volunteers.
[Mh] Termos MeSH primário: Esôfago/fisiologia
Manometria/métodos
[Mh] Termos MeSH secundário: Adulto
Cateterismo/métodos
Esfíncter Esofágico Inferior/fisiologia
Feminino
Hélio
Seres Humanos
Masculino
Satisfação do Paciente
Perfusão
Pressão
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
206GF3GB41 (Helium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180222
[St] Status:MEDLINE
[do] DOI:10.1097/MD.0000000000009910


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[PMID]:29339793
[Au] Autor:Hua Q; Sun J; Liu H; Bao R; Yu R; Zhai J; Pan C; Wang ZL
[Ad] Endereço:CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100083, China.
[Ti] Título:Skin-inspired highly stretchable and conformable matrix networks for multifunctional sensing.
[So] Source:Nat Commun;9(1):244, 2018 01 16.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Mechanosensation electronics (or Electronic skin, e-skin) consists of mechanically flexible and stretchable sensor networks that can detect and quantify various stimuli to mimic the human somatosensory system, with the sensations of touch, heat/cold, and pain in skin through various sensory receptors and neural pathways. Here we present a skin-inspired highly stretchable and conformable matrix network (SCMN) that successfully expands the e-skin sensing functionality including but not limited to temperature, in-plane strain, humidity, light, magnetic field, pressure, and proximity. The actualized specific expandable sensor units integrated on a structured polyimide network, potentially in three-dimensional (3D) integration scheme, can also fulfill simultaneous multi-stimulus sensing and achieve an adjustable sensing range and large-area expandability. We further construct a personalized intelligent prosthesis and demonstrate its use in real-time spatial pressure mapping and temperature estimation. Looking forward, this SCMN has broader applications in humanoid robotics, new prosthetics, human-machine interfaces, and health-monitoring technologies.
[Mh] Termos MeSH primário: Fenômenos Mecânicos
Sensação/fisiologia
Fenômenos Fisiológicos da Pele
Pele/metabolismo
[Mh] Termos MeSH secundário: Técnicas Biossensoriais/instrumentação
Técnicas Biossensoriais/métodos
Seres Humanos
Umidade
Campos Magnéticos
Mecanotransdução Celular/fisiologia
Microscopia Eletrônica de Varredura
Pressão
Pele/citologia
Pele/ultraestrutura
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180118
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02685-9


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[PMID]:29336441
[Au] Autor:Cinar S; Al-Ayoubi S; Sternemann C; Peters J; Winter R; Czeslik C
[Ad] Endereço:Department of Chemistry and Chemical Biology, TU Dortmund University, D-44221 Dortmund, Germany. claus.czeslik@uni-dortmund.de.
[Ti] Título:A high pressure study of calmodulin-ligand interactions using small-angle X-ray and elastic incoherent neutron scattering.
[So] Source:Phys Chem Chem Phys;20(5):3514-3522, 2018 Jan 31.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Calmodulin (CaM) is a Ca sensor and mediates Ca signaling through binding of numerous target ligands. The binding of ligands by Ca -saturated CaM (holo-CaM) is governed by attractive hydrophobic and electrostatic interactions that are weakened under high pressure in aqueous solutions. Moreover, the potential formation of void volumes upon ligand binding creates a further source of pressure sensitivity. Hence, high pressure is a suitable thermodynamic variable to probe protein-ligand interactions. In this study, we compare the binding of two different ligands to holo-CaM as a function of pressure by using X-ray and neutron scattering techniques. The two ligands are the farnesylated hypervariable region (HVR) of the K-Ras4B protein, which is a natural binding partner of holo-CaM, and the antagonist trifluoperazine (TFP), which is known to inhibit holo-CaM activity. From small-angle X-ray scattering experiments performed up to 3000 bar, we observe a pressure-induced partial unfolding of the free holo-CaM in the absence of ligands, where the two lobes of the dumbbell-shaped protein are slightly swelled. In contrast, upon binding TFP, holo-CaM forms a closed globular conformation, which is pressure stable at least up to 3000 bar. The HVR of K-Ras4B shows a different binding behavior, and the data suggest the dissociation of the holo-CaM/HVR complex under high pressure, probably due to a less dense protein contact of the HVR as compared to TFP. The elastic incoherent neutron scattering experiments corroborate these findings. Below 2000 bar, pressure induces enhanced atomic fluctuations in both holo-CaM/ligand complexes, but those of the holo-CaM/HVR complex seem to be larger. Thus, the inhibition of holo-CaM by TFP is supported by a low-volume ligand binding, albeit this is not associated with a rigidification of the complex structure on the sub-ns Å-scale.
[Mh] Termos MeSH primário: Calmodulina/química
Ligantes
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Cálcio/química
Cálcio/metabolismo
Calmodulina/metabolismo
Difração de Nêutrons
Pressão
Ligação Proteica
Espalhamento a Baixo Ângulo
Trifluoperazina/química
Trifluoperazina/metabolismo
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Calmodulin); 0 (Ligands); 214IZI85K3 (Trifluoperazine); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp07399b


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[PMID]:29395085
[Au] Autor:Wan L; Powell-Palm MJ; Lee C; Gupta A; Weegman BP; Clemens MG; Rubinsky B
[Ad] Endereço:Department of Cardiovascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, People's Republic of China; Department of Mechanical Engineering and Department of Bioengineering, University of California, Berkeley, Berkeley, CA, 9472
[Ti] Título:Preservation of rat hearts in subfreezing temperature isochoric conditions to - 8 °C and 78 MPa.
[So] Source:Biochem Biophys Res Commun;496(3):852-857, 2018 02 12.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Isochoric (constant volume) preservation at subfreezing temperatures is being investigated as a novel method for preserving cells and organs. This study is a first initial effort to evaluate the efficacy of this method for heart preservation, and to provide a preliminary outline of appropriate preservation parameters. To establish a baseline for further studies, rat hearts were preserved in a University of Wisconsin (UW) intracellular solution for one hour under isochoric conditions at: 0 °C (atmospheric pressure - 0.1 MPa), - 4 °C (41 MPa), - 6 °C (60 MPa) and - 8 °C (78 MPa). The viability of the heart was evaluated using Langendorff perfusion and histological examination. The physiological performance of hearts preserved at - 4 °C (41 MPa) was comparable to that of a heart preserved on ice at atmospheric pressure, with no statistically significant difference in histological injury score. However, hearts preserved at -4 °C displayed substantially reduced interstitial edema compared to hearts preserved by conventional hypothermic preservation in UW on ice at atmospheric pressure, suggesting significant protection from increased vascular permeability following preservation. Hearts preserved at - 6 °C (60 MPa) suffered injury from cellular swelling and extensive edema, and at - 8 °C (78 MPa) hearts experienced significant morphological disruption. To the best of our knowledge, this is the first publication showing that a mammalian organ can survive low subfreezing temperatures without the use of a cryoprotective additive. Lowering the preservation temperature reduces metabolism and improves preservation quality, and these results suggest that improvements in preservation are possible at subzero temperatures with low to moderate pressures observed at -4 °C. Notably, tissue damage was observed at lower temperatures (-6 °C or below) accompanying further elevation of pressure associated with isochoric preservation that may prove detrimental. Therefore, subfreezing temperature isochoric preservation protocols should optimize, a combination of temperature and pressure that will minimize the negative effects of elevated pressure while retaining the beneficial effect of lower temperatures and reduced metabolism.
[Mh] Termos MeSH primário: Criopreservação/métodos
Coração/fisiologia
Miocárdio/química
Miocárdio/patologia
Soluções para Preservação de Órgãos/química
Preservação de Órgãos/métodos
[Mh] Termos MeSH secundário: Animais
Masculino
Pressão
Ratos
Ratos Sprague-Dawley
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Organ Preservation Solutions)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180204
[St] Status:MEDLINE


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[PMID]:29249634
[Au] Autor:Hirose M; Takano H; Hasegawa H; Tadokoro H; Hashimoto N; Takemura G; Kobayashi Y
[Ad] Endereço:Department of Cardiovascular Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan.
[Ti] Título:The effects of dipeptidyl peptidase-4 on cardiac fibrosis in pressure overload-induced heart failure.
[So] Source:J Pharmacol Sci;135(4):164-173, 2017 Dec.
[Is] ISSN:1347-8648
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Dipeptidyl peptidase-4 (DPP-4) inhibitors are hypoglycemic agents. DPP-4 inhibitor has cardioprotective effects after transverse aortic constriction (TAC), but role of DPP-4 on cardiac fibrosis after TAC is not well known. Our aim was to determine the effects of DPP-4 on cardiac fibrosis in murine TAC model. Wild-type mice and DPP-4 knockout mice were subjected to TAC. Wild-type mice were then treated with vehicle or DPP-4 inhibitor. DPP-4 activities in serum and heart tissue were significantly increased at 2 weeks after TAC, but they were significantly decreased by DPP-4 inhibitor treatment. The inhibition of DPP-4 did not affect left ventricular hypertrophy, but improved cardiac function and decreased myocardial and perivascular fibrosis after TAC. The inhibition of DPP-4 decreased the collagen type III/I ratio in myocardium. These results suggest that DPP-4 inhibition ameliorates the progression of heart failure after TAC by changing the quality and quantity of cardiac fibrosis.
[Mh] Termos MeSH primário: Cardiotônicos
Dipeptidil Peptidase 4/fisiologia
Inibidores da Dipeptidil Peptidase IV/farmacologia
Inibidores da Dipeptidil Peptidase IV/uso terapêutico
Insuficiência Cardíaca/tratamento farmacológico
Insuficiência Cardíaca/etiologia
Miocárdio/patologia
[Mh] Termos MeSH secundário: Animais
Aorta
Estenose da Valva Aórtica/complicações
Colágeno Tipo I/metabolismo
Colágeno Tipo III/metabolismo
Constrição Patológica
Dipeptidil Peptidase 4/metabolismo
Modelos Animais de Doenças
Fibrose
Insuficiência Cardíaca/patologia
Hipertensão/complicações
Hipertrofia
Masculino
Camundongos Endogâmicos C57BL
Miocárdio/metabolismo
Pressão
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cardiotonic Agents); 0 (Collagen Type I); 0 (Collagen Type III); 0 (Dipeptidyl-Peptidase IV Inhibitors); EC 3.4.14.5 (Dipeptidyl Peptidase 4)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE


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[PMID]:29180221
[Au] Autor:Gritti F; Cormier S
[Ad] Endereço:Waters Corporation, 34 Maple Street, Milford, MA 01757, USA. Electronic address: Fabrice_Gritti@waters.com.
[Ti] Título:Performance optimization of ultra high-resolution recycling liquid chromatography.
[So] Source:J Chromatogr A;1532:74-88, 2018 Jan 12.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The optimization of a twin-column recycling separation process (TCRSP) for maximum resolution or maximum speed-resolution was investigated. The general optimization method was based on the construction of kinetic plots by assuming an ideal TCRSP (no efficiency loss upon recycling). For the optimization, we examined three chromatographic parameters: operation pressure (3000, 6000, 9000, and 12,000psi), column length (10, 15, and 25cm), and column inner diameter (i.d.) (2.1, 3.0, and 4.6mm). Accordingly, the highest TCRSP resolution level is expected for 25cm long columns packed with 2.5, 2.0, 1.7, and 1.6µm particles at pressures of 3000, 6000, 9000, and 12,000psi, respectively. The maximum speed-resolution performance is expected for 10cm columns packed with 3.7, 3.0, 2.6, and 2.4µm particles. 3.0mm i.d. columns are best to minimize the negative impacts of thermal and inter-column dispersion effects on the TCRSP performance. The method was illustrated for the challenging separation (selectivity factor α<1.02) of small molecules in RPLC at a maximum pressure of 6000psi using commercially available columns. Accordingly, 3.0×150mm columns packed with 2.5µm cellulose-1 Trefoil particles (chiral separation, γ-phenylbutyrolactone, α=1.01, efficiency N=4500) and 2.7µm Cortecs-C particles (isotope separation, α=1.02, N=14, 500) particles were found to be the most suitable columns to maximize speed-resolution performance. Further optimization of the TCRSP performance was required by reducing the inter-column sample dispersion that could cause undesirable peak tailing. A standard 2.4µL Rheodyne valve and 100µm i.d. tubes were replaced with a home-made 0.5µL low-dispersion prototype valve and 75µm i.d. perfect connection tubes. As a result, the experimental resolution factors were increased by +60% (γ-phenylbutyrolactone, 25 cycles, R =0.7→1.1) and +80% (deuterated benzenes, 22 cycles, R =1.1→2.0). Direct comparison between the experimental and the predicted TCRSP performance unambiguously demonstrated that the resolution gain was explained by the significant reduction of the peak tailing after a large number of cycles (n>20).
[Mh] Termos MeSH primário: Técnicas de Química Analítica/métodos
Cromatografia Líquida/normas
[Mh] Termos MeSH secundário: Benzeno/química
Cinética
Tamanho da Partícula
Pressão
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
J64922108F (Benzene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171129
[St] Status:MEDLINE


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[PMID]:29184921
[Au] Autor:Jaworek MW; Schuabb V; Winter R
[Ad] Endereço:Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, Technical University Dortmund, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany. roland.winter@tu-dortmund.de.
[Ti] Título:The effects of glycine, TMAO and osmolyte mixtures on the pressure dependent enzymatic activity of α-chymotrypsin.
[So] Source:Phys Chem Chem Phys;20(3):1347-1354, 2018 Jan 17.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:High pressure is an important feature of certain natural environments, such as the deep sea where pressures up to about 1000 bar are encountered. Further, pressure effects on biosystems are of increasing interest for biotechnological applications, such as baroenzymology. We studied the effect of two different natural osmolyte mixtures, with major components being glycine and trimethylamine-N-oxide (TMAO), on the activity of α-chymotrypsin, using high-pressure stopped-flow methodology in combination with fast UV/Vis detection. We show that pressure is not only able to drastically enhance the catalytic activity and efficiency of the enzyme, but also that glycine has a significant and diverse effect on the enzymatic activity and volumetric properties of the reaction compared to TMAO. The results might not only help to understand the modulation of enzymatic reactions by natural osmolytes, but also elucidate ways to optimize enzymatic processes in biotechnological applications.
[Mh] Termos MeSH primário: Quimotripsina/metabolismo
Glicina/química
Metilaminas/química
[Mh] Termos MeSH secundário: Quimotripsina/química
Glicina/metabolismo
Hidrólise
Cinética
Metilaminas/metabolismo
Concentração Osmolar
Pressão
Especificidade por Substrato
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Methylamines); EC 3.4.21.1 (Chymotrypsin); EC 3.4.21.1 (alpha-chymotrypsin); FLD0K1SJ1A (trimethyloxamine); TE7660XO1C (Glycine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171130
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06042d



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