Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
1.
J. physiol. biochem ; 72(2): 121-131, jun. 2016. lus, tab, graf
Article in English | IBECS | ID: ibc-168260

ABSTRACT

Insulin secretion and insulin sensitivity indexes are related by hyperbolic functions, allowing the calculation of the disposition index (DI) as the product of the acute insulin response (AIR) and the insulin sensitivity index (Si) from intravenous glucose tolerance test (IVGTT). Our objective was to develop an oral-DI based on the oral glucose tolerance test (OGTT) and to assess its association with glucose tolerance status. This research is structured in three studies. Study 1: OGTT were performed in 833 non-diabetic Chilean women (18-60 years) without family history of diabetes mellitus. Study 2: an independent group of n = 57 non-diabetic (18-46 years) without family history of diabetes mellitus carried out an OGTT and an abbreviated IVGTT. Study 3: a sample of 1674 Chilean adults (18-60 years) with different glycaemic status performed an OGTT. An adequate statistical fit for a rectangular hyperbola was found between the area under the curve of insulin-to-glucose ratio (AUCI/G-R) and the Matsuda ISI-COMP index (study 1). The oral-DI derived as AUCI/G-R × ISI-COMP was previously termed insulin-secretion-sensitivity index-2 (ISSI-2). ISSI-2 significantly correlated with DI from IVGTT (rho = 0.34; p = 0.009) (study 2). ISSI-2 shows important differences across groups of subjects with different glycaemic status (study 3). We have confirmed that ISSI-2 replicates the mathematical properties of DI, showing significant correlations with DI from the abbreviated MM-IVGTT. These results indicate that ISSI-2 constitutes a surrogate measure of insulin secretion relative to insulin sensitivity and emphasizes the pivotal role of impaired insulin secretion in the development of glucose homeostasis dysregulation (AU)


No disponible


Subject(s)
Humans , Male , Female , Adolescent , Young Adult , Adult , Middle Aged , Diabetes Mellitus, Type 2/diagnosis , Insulin , Blood Glucose/analysis , Glucose Intolerance/diagnosis , Prediabetic State/diagnosis , Insulin Resistance/ethnology , Insulin-Secreting Cells , Chile , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/ethnology , Insulin/blood , Glucose Intolerance/blood , Glucose Intolerance/ethnology , Prediabetic State/blood , Prediabetic State/ethnology , Family Health/ethnology , Glucose Tolerance Test
2.
J Physiol Biochem ; 72(2): 121-31, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26660757

ABSTRACT

Insulin secretion and insulin sensitivity indexes are related by hyperbolic functions, allowing the calculation of the disposition index (DI) as the product of the acute insulin response (AIR) and the insulin sensitivity index (Si) from intravenous glucose tolerance test (IVGTT). Our objective was to develop an oral-DI based on the oral glucose tolerance test (OGTT) and to assess its association with glucose tolerance status. This research is structured in three studies. Study 1: OGTT were performed in 833 non-diabetic Chilean women (18-60 years) without family history of diabetes mellitus. Study 2: an independent group of n = 57 non-diabetic (18-46 years) without family history of diabetes mellitus carried out an OGTT and an abbreviated IVGTT. Study 3: a sample of 1674 Chilean adults (18-60 years) with different glycaemic status performed an OGTT. An adequate statistical fit for a rectangular hyperbola was found between the area under the curve of insulin-to-glucose ratio (AUCI/G-R) and the Matsuda ISI-COMP index (study 1). The oral-DI derived as AUCI/G-R × ISI-COMP was previously termed insulin-secretion-sensitivity index-2 (ISSI-2). ISSI-2 significantly correlated with DI from IVGTT (rho = 0.34; p = 0.009) (study 2). ISSI-2 shows important differences across groups of subjects with different glycaemic status (study 3). We have confirmed that ISSI-2 replicates the mathematical properties of DI, showing significant correlations with DI from the abbreviated MM-IVGTT. These results indicate that ISSI-2 constitutes a surrogate measure of insulin secretion relative to insulin sensitivity and emphasizes the pivotal role of impaired insulin secretion in the development of glucose homeostasis dysregulation.


Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Type 2/diagnosis , Glucose Intolerance/diagnosis , Insulin Resistance , Insulin-Secreting Cells/metabolism , Insulin/metabolism , Prediabetic State/diagnosis , Adolescent , Adult , Chile , Cross-Sectional Studies , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/ethnology , Diabetes Mellitus, Type 2/metabolism , Family Health/ethnology , Female , Glucose Intolerance/blood , Glucose Intolerance/ethnology , Glucose Intolerance/metabolism , Glucose Tolerance Test , Humans , Insulin/blood , Insulin Resistance/ethnology , Insulin Secretion , Male , Middle Aged , Practice Guidelines as Topic , Prediabetic State/blood , Prediabetic State/ethnology , Prediabetic State/metabolism , Sensitivity and Specificity , Young Adult
3.
Appl Environ Microbiol ; 62(4): 1295-9, 1996 Apr.
Article in English | MEDLINE | ID: mdl-16535293

ABSTRACT

Streptomyces citreus CBS 109.60 produced geosmin and a complex pattern of other volatile compounds during cultivation in a 2.5-liter laboratory bioreactor. Volatiles were isolated from disrupted cells, from the culture medium, and from the waste air of the bioreactor by adsorption on Lewatit OC 1064MD. Quantitative and qualitative analyses were carried out using capillary gas chromatography and coupled gas chromatography-mass spectroscopy. S. citreus produced 56 volatile compounds, which were mainly terpenoids but also included aliphatic ketones, alcohols, esters, pyrazines, furan(on)es, and aromatic types during the growth phase. The major components were geosmin and a germacradienol. A biosynthetic pathway for geosmin including eudesmanolides is proposed.

4.
Rev Med Chil ; 123(2): 145-57, 1995 Feb.
Article in Spanish | MEDLINE | ID: mdl-7569454

ABSTRACT

We studied 90 male non diabetic patients aged between 40 and 65 years old with a total cholesterol of less than 240 mg/dl and not receiving cholesterol reducing drugs, that were subjected to elective coronary arteriography. Weight, height, blood pressure and smoking habits were recorded and a fasting blood sample was drawn to measure total and HDL cholesterol, triglycerides, apoproteins A1 and B, Lipoprotein(a) and plasma cholesteryl ester transfer activity. Arteriography disclosed coronary lesions in 54 patients. Compared to patients without lesions, the former had lower HDL cholesterol (34 +/- 9.8 vs 40.2 +/- 11.6 mg/dl) and higher total cholesterol/HDL cholesterol and apoB/apoA1 ratios. No differences were found for lipoprotein(a) and plasma cholesteryl ester transfer activity. Univariate analysis showed that low HDL cholesterol had the best predictive capacity for atherosclerosis.


Subject(s)
Cholesterol/blood , Coronary Artery Disease/etiology , Adult , Aged , Analysis of Variance , Apolipoprotein A-I/blood , Apolipoproteins B/blood , Cholesterol Esters/blood , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Coronary Angiography , Coronary Artery Disease/blood , Coronary Artery Disease/diagnosis , Diabetes Mellitus/blood , Humans , Lipoprotein(a)/blood , Male , Middle Aged , Predictive Value of Tests , Regression Analysis , Risk Factors , Sensitivity and Specificity , Triglycerides/blood
6.
Rofo ; 149(4): 402-7, 1988 Oct.
Article in German | MEDLINE | ID: mdl-2845509

ABSTRACT

In a retrospective study, the results of real-time sonography and grid mammography in 161 patients with histologically confirmed breast cancer were analyzed and compared with the histopathologic characteristics of the tumours to assess the diagnostic accuracy of these preoperative image-producing methods. The results showed the determination of the tumour size as obtained by the image-producing methods to correlate closely with the histopathologic findings. Furthermore, both real-time sonography and mammography yielded certain indications allowing prognostically valuable conclusions in respect of malignancy and invasiveness of the carcinomas. Taking into account the different but complementing diagnostic results of both methods, the combination of grid mammography and real-time sonography must be considered as the presently most reliable preoperative diagnostic procedure.


Subject(s)
Breast Neoplasms/pathology , Mammography , Ultrasonography , Breast Neoplasms/diagnostic imaging , Carcinoma/diagnostic imaging , Carcinoma/pathology , Carcinoma, Intraductal, Noninfiltrating/diagnostic imaging , Carcinoma, Intraductal, Noninfiltrating/pathology , Female , Humans
7.
Appl Opt ; 16(11): 2858-60, 1977 Nov 01.
Article in English | MEDLINE | ID: mdl-20174256

ABSTRACT

We have developed a unique approach for evaluating the local composition x as a function of position on the surface of crystals of Hg(1-x) Cd(x) Te utilizing electrolyte electroreflectance. The method is nondestructive and can be employed at room temperature. The technique is sensitive enough to determine changes of composition Deltax approximately 0.002 for samples in which x approximately 0.2-0.3 with a spatial resolution of about 150 microm. This approach has a number of advantages over the microprobe technique.

SELECTION OF CITATIONS
SEARCH DETAIL
...