RESUMO
Thermal behavior at subzero temperatures has been investigated for aqueous solutions of various monosaccharides. The heat of fusion of ice measured with differential scanning calorimetry has given linear plots against sugar concentration (wt.%), from which the amount of unfrozen water, Uw, has been determined for each monosaccharide. The results for Uw are analyzed by employing, as a measure of hydration characteristics, known physico-chemical properties of aqueous monosaccharides, such as partial molar compressibilities, etc. It was revealed that the anti-freeze characteristics of carbohydrates depend on their stereochemistry. More water remains unfrozen in the aqueous solutions of carbohydrates having poorer compatibility with the three-dimensional hydrogen-bond network of water. Monosaccharides studied can be subdivided into three groups according to the extent of the anti-freeze effect. These results are rationalized in terms of a modified stereospecific hydration model.
Assuntos
Carboidratos/química , Congelamento , Monossacarídeos/química , Varredura Diferencial de Calorimetria/métodos , Gelo , Cinética , Estereoisomerismo , TemperaturaRESUMO
The new lignan derivative, erimopyrone, was isolated from the liverwort, Moerckia erimona. Its structure was established as [1R, 2S]-1(6-carboxy-2-oxo-2H-4-pyranyl)- 6,7-dihydroxy-1,2-dihydro-2,3-naphthalenedicarboxylic acid by spectroscopic methods.
RESUMO
We evaluated the association between coronary spasm and hyperinsulinemia (high immunoreactive insulin, IRI) in patients with angina pectoris. The study cohort comprised 30 patients with spastic angina pectoris, 30 patients with angina pectoris showing fixed-obstructive coronary sclerosis and 30 control subjects who were matched for body mass index, age and sex. A 75-gram oral glucose test was performed, and blood sugar and IRI were serially measured concomitant with serum total cholesterol, triglyceride and HDL cholesterol. The IRI level at 60 min, the peak IRI during the test, sigma IRI and sigma IRI/sigma blood sugar were significantly higher in the patients than in the controls. Total cholesterol and LDL cholesterol levels were significantly increased in patients showing fixed-obstructive coronary sclerosis compared to controls.
Assuntos
Angina Pectoris Variante/complicações , Glicemia/metabolismo , Hiperinsulinismo/complicações , Insulina/sangue , Acetilcolina/administração & dosagem , Angina Pectoris Variante/sangue , Angina Pectoris Variante/diagnóstico , Angina Instável/sangue , Angina Instável/complicações , Angina Instável/diagnóstico , Índice de Massa Corporal , Colesterol/sangue , HDL-Colesterol/sangue , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Diagnóstico Diferencial , Feminino , Teste de Tolerância a Glucose , Humanos , Hiperinsulinismo/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangueRESUMO
Effects of the experimentally induced hypotension with 4 vasodilators; nitroglycerin (TNG), prostaglandin E1 (PGE1), trimetaphan (TMP) and nicardipine (NCP) on systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and pulmonary-systemic vascular resistance ratio (PVR/SVR ratio) were studied in dogs. The SVR values were significantly reduced by TNG, PGE1 and NCP, and not affected by TMP. The PVR values were significantly reduced by TNG and PGE1, and not affected by TMP and NCP. The PVR/SVR ratio values were significantly reduced by TNG, and significantly increased by NCP, and not affected by PGE1 and TMP. We concluded that TNG reduced PVR and SVR but it affected PVR more; PGE1 reduced PVR and SVR equivalently; TMP did not affect PVR and SVR remarkably; NCP reduced SVR but did not affect PVR.
Assuntos
Alprostadil/farmacologia , Hipotensão Controlada , Nicardipino/farmacologia , Nitroglicerina/farmacologia , Artéria Pulmonar/efeitos dos fármacos , Trimetafano/farmacologia , Resistência Vascular/efeitos dos fármacos , Animais , Cães , Artéria Pulmonar/fisiologiaRESUMO
Computed tomograms of 150 cases with bone metastasis of various malignant neoplastic diseases are reviewed. According to CT findings bone metastasis is classified into six types, namely osteoblastic, mixed, osteolytic with sclerotic rim, osteolytic with sclerotic center, osteolytic, and infiltrative. Presumably many bone metastases show initially osteoblastic type on CT, and change progressively to mixed type or osteolytic type. If chemotherapy or radiotherapy is effective for bone metastasis, CT demonstrates changes of inverse direction. In detection of bone metastasis CT is superior to radionuclide bone scan. To find out the bone metastasis CT of cancer patients must be evaluated with bone window.
