Browsing by Author "Trbojević, Božo (6602073472)"

Objective: The aim of the study was to determine whether derangements in insulin pulsatility are related to the presence of insulin resistance or whether these changes occur only in non-insulin-dependent diabetes mellitus (NIDDM). Design and methods: The study included 26 obese, 11 NIDDM and 10 control subjects. The obese group was divided into a low insulin (plasma insulin <20 mU/l, OLI, 14 subjects) and a high insulin (OHI, 12 subjects) group. For pulsatility analysis blood was sampled every 2 min for 90 min. Pulsatility analysis was carried out using the PulsDetekt program. The insulin secretion randomness was quantified using interpulse interval deviation (IpID) and approximate entropy (ApEn). ApEn and ApEn normalized by s.p. of the individual insulin time series (nApEn) were calculated. Lower values of ApEn and IpID indicate more regular secretion. Homeostasis model assessment (HOMA) was used to quantify insulin sensitivity. Results: Insulin pulses were significantly less regular in the OHI and the NIDDM groups compared with the control and the OLI groups (control: ApEn 0,54 ± 0.16, nApEn 0.69 ± 0.19, IpID 2.53 ± 0.99; OLI: ApEn 0.64 ± 0.12, nApEn 0.79 ± 0.15, IpID 2.92 ± 1.09; OHI: ApEn 0.88 ± 0.07, nApEn 0.92 ± 0.07, IpID 3.95 ± 0.84; NIDDM: ApEn 0.92 ± 0.16, nApEn 0.99 ± 0.09, IpID 4.41 ± 0.53; means ± s.p.). There was no difference in the pulse regularity between the OHI and the NIDDM groups. Conclusions: Decrease in insulin sensitivity was correlated with the reduction of insulin secretion regularity. Therefore irregular insulin secretion is related to a reduction in insulin sensitivity, and it is not unique to NIDDM.

Objective: The aim of the study was to determine whether derangements in insulin pulsatility are related to the presence of insulin resistance or whether these changes occur only in non-insulin-dependent diabetes mellitus (NIDDM). Design and methods: The study included 26 obese, 11 NIDDM and 10 control subjects. The obese group was divided into a low insulin (plasma insulin <20 mU/l, OLI, 14 subjects) and a high insulin (OHI, 12 subjects) group. For pulsatility analysis blood was sampled every 2 min for 90 min. Pulsatility analysis was carried out using the PulsDetekt program. The insulin secretion randomness was quantified using interpulse interval deviation (IpID) and approximate entropy (ApEn). ApEn and ApEn normalized by s.p. of the individual insulin time series (nApEn) were calculated. Lower values of ApEn and IpID indicate more regular secretion. Homeostasis model assessment (HOMA) was used to quantify insulin sensitivity. Results: Insulin pulses were significantly less regular in the OHI and the NIDDM groups compared with the control and the OLI groups (control: ApEn 0,54 ± 0.16, nApEn 0.69 ± 0.19, IpID 2.53 ± 0.99; OLI: ApEn 0.64 ± 0.12, nApEn 0.79 ± 0.15, IpID 2.92 ± 1.09; OHI: ApEn 0.88 ± 0.07, nApEn 0.92 ± 0.07, IpID 3.95 ± 0.84; NIDDM: ApEn 0.92 ± 0.16, nApEn 0.99 ± 0.09, IpID 4.41 ± 0.53; means ± s.p.). There was no difference in the pulse regularity between the OHI and the NIDDM groups. Conclusions: Decrease in insulin sensitivity was correlated with the reduction of insulin secretion regularity. Therefore irregular insulin secretion is related to a reduction in insulin sensitivity, and it is not unique to NIDDM.

The aim of the study was to assess whether pulsatile insulin secretion is variable in the same individual and is related to changes in insulin sensitivity. Insulin sensitivity and pulsatility were measured before and after weight reduction in nine obese subjects. A pulsatility analysis was done using the PulsDetekt program. Blood was sampled every 2 min over a period of 90 min. The secretion randomness was quantified using approximate entropy (ApEn), and ApEn normalized by SD of the insulin time series (nApEn). Lower values indicate more regular secretion. Insulin sensitivity was measured using the homeostasis model assessment. Data are presented as median, minimum-maximum. After weight loss insulin sensitivity was increased (12.16, 7.60-76.70 vs. 38.96, 19.88-74.96%), the number of insulin pulses was reduced (11, 8-16 vs. 9, 6-12), and they were more regular (ApEn, 0.92, 0.53-133 vs. 0.69, 0,40-1.27; nApEn, 1.07, 0.74-1.33 vs. 0.97, 0.54-1.42). Before and after the weight loss there was a correlation between ApEn and nApEn and insulin sensitivity. Therefore, insulin secretion regularity is variable in the same individual and is related to insulin sensitivity.

The aim of the study was to assess whether pulsatile insulin secretion is variable in the same individual and is related to changes in insulin sensitivity. Insulin sensitivity and pulsatility were measured before and after weight reduction in nine obese subjects. A pulsatility analysis was done using the PulsDetekt program. Blood was sampled every 2 min over a period of 90 min. The secretion randomness was quantified using approximate entropy (ApEn), and ApEn normalized by SD of the insulin time series (nApEn). Lower values indicate more regular secretion. Insulin sensitivity was measured using the homeostasis model assessment. Data are presented as median, minimum-maximum. After weight loss insulin sensitivity was increased (12.16, 7.60-76.70 vs. 38.96, 19.88-74.96%), the number of insulin pulses was reduced (11, 8-16 vs. 9, 6-12), and they were more regular (ApEn, 0.92, 0.53-133 vs. 0.69, 0,40-1.27; nApEn, 1.07, 0.74-1.33 vs. 0.97, 0.54-1.42). Before and after the weight loss there was a correlation between ApEn and nApEn and insulin sensitivity. Therefore, insulin secretion regularity is variable in the same individual and is related to insulin sensitivity.

More than a half century of experience with aspiration punch of nodal changes in the thyroid gland has confirmed this procedure as a golden standard in the examination of thyroid nodal disease. Although sensitivity, specificity, reliability and reproducibility are incontestably high, this procedure cannot give a simple answer on whether the change examined is benign or malignant. Numerous attempts to improve the procedure resulted in considerably advanced findings. Besides refining the cytopathologic examination techniques, confirmation or determination of hormones, proteins and other substances in the material obtained by fine-needle aspiration are actually the greatest contribution to improvement the of procedure's diagnostic value. These markers are actually followed, in most medical centers, in aspirates of thyroid nodal changes but also surrounding lymph nodes in order to evaluate with greater certainty the type, volume and spread; this is important to establish treatment procedures and to evaluate the residual disease after accomplishing the treatment.

More than a half century of experience with aspiration punch of nodal changes in the thyroid gland has confirmed this procedure as a golden standard in the examination of thyroid nodal disease. Although sensitivity, specificity, reliability and reproducibility are incontestably high, this procedure cannot give a simple answer on whether the change examined is benign or malignant. Numerous attempts to improve the procedure resulted in considerably advanced findings. Besides refining the cytopathologic examination techniques, confirmation or determination of hormones, proteins and other substances in the material obtained by fine-needle aspiration are actually the greatest contribution to improvement the of procedure's diagnostic value. These markers are actually followed, in most medical centers, in aspirates of thyroid nodal changes but also surrounding lymph nodes in order to evaluate with greater certainty the type, volume and spread; this is important to establish treatment procedures and to evaluate the residual disease after accomplishing the treatment.

ACTH stimulation is the standard test for assessment of adrenal function. It was suggested that the low dose (1 μg) would be more sensitive for detecting mild secondary adrenal insufficiency than the usual dose of 250 μg. The aim of this study was to find the optimal diagnostic criteria and to compare standard dose test (SDT) with the low dose test (LDT). A group of patients treated with corticosteroids for the 6 months was considered to have hypothalamo-pituitary-adrenal impairment. Studies were performed in 14 corticosteroid-treated and 28 control subjects in random order on 2 consecutive days. Tests were analyzed using the receiver operating characteristic curve method. The best test was cortisol increment at 15 min of the LDT. It was significantly better than the cortisol concentration at 15 min of the SDT, the best test during the SDT (receiver operating characteristic curve area and 95% confidence interval: LDT, 0.997 and 0.956-0.999; SDT, 0.827 and 0.662-0.929; P = 0.0113). For the cortisol increment at 15 min of the LDT at 100% sensitivity, the diagnostic value was 100 mmol/L, and the specificity was 96%. Therefore, the LDT is superior to the standard dose test in the assessment of secondary adrenal insufficiency.

ACTH stimulation is the standard test for assessment of adrenal function. It was suggested that the low dose (1 μg) would be more sensitive for detecting mild secondary adrenal insufficiency than the usual dose of 250 μg. The aim of this study was to find the optimal diagnostic criteria and to compare standard dose test (SDT) with the low dose test (LDT). A group of patients treated with corticosteroids for the 6 months was considered to have hypothalamo-pituitary-adrenal impairment. Studies were performed in 14 corticosteroid-treated and 28 control subjects in random order on 2 consecutive days. Tests were analyzed using the receiver operating characteristic curve method. The best test was cortisol increment at 15 min of the LDT. It was significantly better than the cortisol concentration at 15 min of the SDT, the best test during the SDT (receiver operating characteristic curve area and 95% confidence interval: LDT, 0.997 and 0.956-0.999; SDT, 0.827 and 0.662-0.929; P = 0.0113). For the cortisol increment at 15 min of the LDT at 100% sensitivity, the diagnostic value was 100 mmol/L, and the specificity was 96%. Therefore, the LDT is superior to the standard dose test in the assessment of secondary adrenal insufficiency.