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1.
Ann Vasc Surg ; 48: 67-74, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29217439

RESUMO

BACKGROUND: We previously reported the utility of the perfusion value (PV) fluctuation slope for detecting severe ischemia in the lower limb. Our approach was based on a thermal load test mimicking the well-known physiological reaction termed "cold-induced vasodilation," which is known to occur as a 3-phase phenomenon. The slope parameter quantifies the decrease in PVs accompanying the relative cooling (third phase) following the transient increase in blood flow (second phase) induced by the applied thermal load. This phenomenon of "relative" cold-induced vasodilation (rCIVD) can be monitored using laser speckle contrast imaging (LSCI) after applying the thermal load (LTL test). Here, we aimed to determine whether the slope parameter obtained via the LTL test also reflects the improvement in hemodynamics after revascularization. METHODS: The study enrolled 16 patients (18 limbs), who underwent revascularization for peripheral arterial disease (PAD). The measurements were performed at 2 sites in each limb (in total, 34 sites; 2 sites in one patient were excluded because of significant movement during the measurement). For each site, we recorded the slope describing the behavior of PVs (decrease or plateau) in the third phase of rCIVD, following the initial, heating-induced increase in perfusion (second phase of rCIVD). The plateau group (group P), which included patients with an abnormal rCIVD, and the decrease group (group D), which included patients with a normal rCIVD, were defined based on perfusion slope values of <0.20 and ≥ 0.20 perfusion units/min, respectively. We also quantified the transient increase in perfusion (from baseline to peak) as a descriptor of perfusion behavior during the second phase of rCIVD. RESULTS: In group P, the change in median values (25-75%) of the slope, transcutaneous oxygen tension, and ankle-brachial index (ABI) from before to after operation was (-0.02 [-0.04 to 0.02]; 4 [1-11]; and 0.08 [0-0.27]) to (0.39 [0.32-0.59]; 46 [37-54]; and 0.81 [0.72-0.90]). Conversely, in group D, the change in the median values of the slope, transcutaneous oxygen tension, and ABI between before and after operation was (0.38 [0.32-0.49]; 40.5 [35-45]; and0.58 [0.57-0.65]) to (0.44 [0.30-0.64]; 52 [43-56]; and 0.92 [0.81-0.99]). Sites exhibiting perfusion pattern of group D in the third phase of rCIVD showed no significant change in slope after revascularization (P = 0.21), whereas the slope in group P increased significantly after revascularization, becoming similar to the postoperative slopes in group D (P = 0.81). The amount of transient increase in perfusion, which quantified the behavior in the second phase of rCIVD, showed a similar behavior. Preoperatively, all patients in group P had rest pain and/or ulcer of the foot, whereas only few patients in group D had such symptoms. CONCLUSIONS: Normal rCIVD response in the LTL test indicates less-than-severe ischemia, while abnormal rCIVD response measured via the LTL test indicates severe ischemic symptoms, such as critical limb ischemia. Notably, patients with an abnormal rCIVD response can develop a normal rCIVD response following revascularization, thereby reflecting an improvement in blood flow. The LTL test assessing rCIVD response can be useful for detecting severe limb ischemia, such as critical limb ischemia (CLI), and determining the departure from severe limb ischemia by revascularization.


Assuntos
Hemodinâmica , Hipertermia Induzida , Isquemia/cirurgia , Extremidade Inferior/irrigação sanguínea , Imagem de Perfusão/métodos , Doença Arterial Periférica/cirurgia , Ultrassonografia/métodos , Idoso , Idoso de 80 Anos ou mais , Índice Tornozelo-Braço , Velocidade do Fluxo Sanguíneo , Monitorização Transcutânea dos Gases Sanguíneos , Feminino , Humanos , Isquemia/diagnóstico por imagem , Isquemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
2.
J Food Sci ; 80(7): C1453-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26036167

RESUMO

UNLABELLED: Catalytic isomerization of (all-E)-lycopene to Z-isomers using iron(III) chloride was investigated and optimized under various conditions of solvents, concentrations of iron(III) chloride, and reaction temperatures. The total contents of Z-isomers converted were higher in the order of CH2 Cl2 (78.4%) > benzene (61.4%) > acetone (51.5%) > ethyl acetate (50.8%) at 20 °C for 3 h using 1.0 × 10(-3) mg/mL iron(III) chloride for 0.1 mg/mL (all-E)-lycopene. However, the decomposition of lycopene was markedly accelerated in CH2 Cl2 : the remaining lycopene after the reaction for 3 h and 12 h was only 79.4% and 47.5%, respectively. As the concentration of catalyst increased in acetone, the Z-isomerization ratio of lycopene increased to more than 80%, followed by rapid degradation of lycopene to undetectable levels using >4.0 × 10(-3) mg/mL iron(III) chloride with the above concentration of (all-E)-lycopene. Finally, greater isomerization (79.9%) was attained at 60 °C in acetone for 3 h in the presence of 1.0 × 10(-3) mg/mL iron(III) chloride, largely without decomposition of lycopene (remaining ratio of total amount of lycopene isomers after the reaction, 96.5%). As iron(III) chloride has found general use as a food additive for iron fortification and acetone is also widely used in the food field, this method can be applied to the food and beverage processing industry. PRACTICAL APPLICATION: The dietary intake of lycopene, a natural red pigment found in brightly colored vegetables and fruits such as tomatoes and watermelons, has been reported to lower the risk of some diseases, including cancer. Lycopene molecules occur naturally in a long and "straight" shape, but on the other hand lycopene molecules with "bent" forms are highly absorbed by living cells, and showed good antioxidant activity. This study has demonstrated the efficient production of the "bent" lycopene using ionic iron as an accelerator, which is often contained in nutritional supplements.


Assuntos
Carotenoides/química , Cloretos/química , Compostos Férricos/química , Acetona/química , Bebidas , Catálise , Indústria Alimentícia , Ferro , Licopeno , Solanum lycopersicum/química , Solventes , Estereoisomerismo , Temperatura
3.
Food Chem ; 171: 323-9, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25308676

RESUMO

The geometric isomerisation of (all-E)-lycopene, purified from tomato paste, was investigated in various organic solvents. Isomerisation ratios to the Z-isomers of lycopene in CH2Cl2 and CHCl3 over 24h were calculated to be 19.7% and 11.4% at 4°C and 77.8% and 48.4% at 50°C, respectively. In CH2Br2, more than 60% was attained in the first several hours, independent of temperature. The predominant Z-isomers obtained thermally, (9Z)-lycopene and (13Z)-lycopene, were purified and their absorption maxima and molar extinction coefficients in hexane were determined for the first time. Absorption values at 460 nm were also measured for both Z-isomers along with (all-E)-lycopene to accurately evaluate their concentrations by HPLC analysis. This approach successfully revealed that (13Z)-lycopene formed predominantly in benzene or CHCl3 at 50°C; in contrast, the 5Z-isomer was preferentially obtained in CH2Cl2 or CH2Br2.


Assuntos
Carotenoides/química , Temperatura Alta , Solventes , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Isomerismo , Licopeno , Solanum lycopersicum/química
4.
J Agric Food Chem ; 62(1): 264-9, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24354592

RESUMO

A large amount of (all-E)-lycopene was successfully purified from tomato paste using an improved method that included a procedure to wash crystalline powder with acetone. The total yield of the pure (all-E) form was at least 30%. The melting point of (all-E)-lycopene was determined to be 176.35 °C by differential scanning calorimetry (DSC) measurements. Bathochromic shifts were observed in the absorption maxima of all solvents tested (at most a 36 nm shift for λ2 in carbon disulfide, as was observed in hexane) and were accompanied by absorbance decreases, namely, a hypochromic effect, showing a higher correlation between the position and the intensity of the main absorption bands. This bathochromic shift was dependent upon the polarizability of the solvent rather than its polarity. The structure of (all-E)-lycopene in CDCl3 and C6D6 was identified on the basis of one- and two-dimensional nuclear magnetic resonance (NMR) spectra, including (1)H and (13)C NMR, homonuclear correlation spectroscopy ((1)H-(1)H COSY), heteronuclear multiple-quantum coherence (HMQC), and heteronuclear multiple-bond connectivity (HMBC). The rate constants of the decrease in (all-E)-lycopene with hexane and benzene were calculated to be 3.19 × 10(-5) and 3.55 × 10(-5) s(-1), respectively. The equilibrium constants between (all-E) and (13Z) isomers were estimated to be 0.29 in hexane and 0.31 in benzene, respectively, from the point at which the amount of (13Z)-lycopene reached its maximum.


Assuntos
Carotenoides/química , Extratos Vegetais/química , Solanum lycopersicum/química , Carotenoides/isolamento & purificação , Temperatura Alta , Isomerismo , Cinética , Licopeno , Espectroscopia de Ressonância Magnética , Extratos Vegetais/isolamento & purificação , Temperatura de Transição
5.
Food Chem ; 138(2-3): 866-9, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23411189

RESUMO

A convenient HPLC method for the quantitative determination of EDTA in foods was developed. EDTA in food samples was easily extracted with water by ultrasonication. After converting to Fe(III) complex in the presence of Fe(III) ions, EDTA was separated on a reversed-phase C30 column and detected with ultraviolet detection (260 nm). Citrate and malate, which are present in many foods, also formed Fe(III) complexes but they did not interfere the chromatographic detection of EDTA. The method allowed determination of EDTA in foods at concentrations as low as 0.01 mmol/kg. Good recoveries (95.2-101%) were obtained by the standard addition method on four samples with high repeatability (RSD, 0.8-3.4%). The method was successfully applied to the analysis of EDTA in carbonated drinks, jellies, canned beans, canned corn and food supplements.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Ácido Edético/análise , Análise de Alimentos/métodos
6.
Surg Today ; 37(2): 103-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17243026

RESUMO

PURPOSE: To investigate the effects of acupressure on lower limb blood flow for the treatment of peripheral arterial occlusive diseases (PAOD). METHODS: From February 2004 to February 2005, 30 patients with stage II PAOD underwent measurements of the lower limb blood flow. Six patients (group A) were assigned as controls without any acupoint stimulation, while 24 (group B) underwent stimulation at acupoints by acupressure. The acupoints Yanglingquan (GB34), Zusanli (ST36), Yinlingquan (SP9), and Sanyinjiao (SP6) of the symptomatic lower limbs were stimulated for 3 min. Transcutaneous oximetry (tcPO2) was used to determine the blood flow of the chest wall, bilateral distal crura, and bilateral dorsa of the foot before and during the stimulations at the acupoints. RESULTS: Group A showed no significant change in the lower limb blood flow. In group B, the tcPO2 values of chest wall, bilateral distal crura, and the dorsum of foot of the stimulated lower limb increased significantly during acupressure (P < 0.01), whereas no significant change was shown in the dorsum of the foot of the non-stimulated lower limb. Moreover, the blood flow of the lower limbs that had undergone an ipsilateral sympathectomy increased significantly (P < 0.01). CONCLUSIONS: Acupressure was found to cause significant increases in the lower limb blood flow of stage II PAOD patients. This treatment modality may therefore be effective for improving the symptoms of such patients.


Assuntos
Acupressão/métodos , Arteriopatias Oclusivas/fisiopatologia , Arteriopatias Oclusivas/terapia , Velocidade do Fluxo Sanguíneo/fisiologia , Perna (Membro)/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Angiografia , Arteriopatias Oclusivas/diagnóstico , Monitorização Transcutânea dos Gases Sanguíneos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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