Effect of hemolysis on Fourier transform infrared and Raman spectra of blood plasma

Hemolysis is a very common phenomenon and is referred as the release of intracellular components from red blood cells to the extracellular fluid. Hemolyzed samples are often rejected in clinics due to the interference of hemoglobin and intracellular components in laboratory measurements. Plasma and serum based vibrational spectroscopy studies are extensively applied to generate spectral biomarkers for various diseases. However, no studies have reported the effect of hemolysis in blood based vibrational spectroscopy studies. This study was undertaken to evaluate the effect of hemolysis on infrared and Raman spectra of blood plasma. In this study, prostate cancer plasma samples (n = 30) were divided into three groups (nonhemolyzed, mildly hemolyzed, and moderately hemolyzed) based on the degree of hemolysis and FTIR and Raman spectra were recorded using high throughput (HT)‐FTIR and HT‐Raman spectroscopy. Discrimination was observed between the infrared and Raman spectra of nonhemolyzed and hemolyzed plasma samples using principal component analysis. A classical least square fitting analysis showed differences in the weighting of pure components in nonhemolyzed and hemolyzed plasma samples. Therefore, it is worth to consider the changes in spectral features due to hemolysis when comparing the results within and between experiments.     

IMPROVED HBA1C,TOTAL DAILY INSULIN DOSE,AND TREATMENT SATISFACTION WITH INSULIN PUMP THERAPY COMPARED TO MULTIPLE DAILY INSULIN INJECTIONS IN PATIENTS WITH TYPE 2 DIABETES IRRESPECTIVE OF BASELINE C-PEPTIDE LEVELS

Objective: Fasting C-peptide levels are used to differentiate type 1 from type 2 diabetes (T2D), thereby determining eligibility for coverage of continuous subcutaneous insulin infusion (CSII) for patients with T2D.Methods: A total of 168 patients (74 female/94 male, aged 55.5 ± 9.7 years) were randomized to CSII, and 163 patients (77 female/86 male, aged 56.4 ± 9.5 years) were randomized to multiple daily injections (MDI) of insulin and grouped by baseline C-peptide level: group A (≤183 pmol/L [≤0.55 ng/mL]); group B (>183 pmol/L [>0.55 ng/mL]). At 6 months, the MDI group crossed over to CSII. Within- and between-group comparisons were recorded at 6 and 12 months in the entire group and separately for those patients aged ≥65 years.Results: CSII reduced hemoglobin A1c (A1c) equally in groups A (P = .0006, P = .0022) and B (P<.0001, P<.0001) at 6 and 12 months, respectively. There was an increase in weight in group A versus group B at 6 months but not 12 months (P<.03). CSII therapy reduced total daily dose (TDD) of insulin and improved treatment satisfaction similarly in groups A and B. The results for patients aged ≥65 years displayed a similar trend as the entire group.Conclusion: A1c, TDD of insulin, and treatment satisfaction improved for T2D patients using CSII versus MDI therapy, irrespective of baseline C-peptide level. A subgroup of patients aged ≥65 years displayed a similar trend. These results support abandoning C-peptide as a criterion for reimbursing CSII therapy in patients with diabetes.Abbreviations: A1c = hemoglobin A1c; CMS = Centers for Medicare and Medicaid Services; CSII = continuous subcutaneous insulin infusion; DTSQ = Diabetes Treatment Satisfaction Questionnaire; MDI = multiple daily injections; RCT = randomized controlled trials; T1D = type 1 diabetes; T2D = type 2 diabetes; TDD = total daily dose     

The Long-Term Impact Of Controlled Ovarian Hyperstimulation On Thyroid Function

Objective: Evidence on the long-term impact of controlled ovarian hyperstimulation (COH) on thyroid function is scarce. To investigate this, we report on serum thyroid-stimulating hormone (TSH) modifications in euthyroid and hypothyroid women during COH and 3 months after the end of the stimulation cycle.Methods: Women who underwent in vitro fertilization (IVF) and who did not become pregnant were eligible. Cases were women with treated hypothyroidism and basal serum TSH <2.5 mIU/L. Controls were euthyroid women matched to cases by age and basal serum TSH. Women could be included if serum TSH was available at 4 time points: prior to initiating COH (time 1); at the time of human chorionic gonadotropin (hCG) administration (time 2); 16 days after hCG administration (time 3); and 3 months after the end of the IVF cycle (time 4).Results: Thirty-seven case-control pairs were included. Serum TSH at times 1, 2, 3, and 4 was 1.7 ± 0.6, 3.1 ± 1.4, 3.1 ± 1.3, and 2.7 ± 1.7 mIU/L, and 1.7 ± 0.6, 2.9 ± 1.0, 2.7 ± 1.0, and 1.9 ± 0.7 mIU/L among cases and controls, respectively. A statistically significant difference emerged at time 4 (P<.001). In both groups, serum TSH was higher at time 4 compared to time 1. Serum TSH exceeded the recommended threshold of 2.5 mIU/L at time 4 in 51% of cases (95% confidence interval &lsqb;CI], 35 to 68%) and in 16% of controls (95% CI, 4 to 28%) (P = .003).Conclusion: COH seems to have a long-term impact on TSH levels. The magnitude of this effect is particularly pronounced in hypothyroid women.Abbreviations:CI = confidence intervalCOH = controlled ovarian hyperstimulationFT4 = free thyroxinehCG = human chorionic gonadotropinIVF = in vitro fertilizationT4 = thyroxineTBG = thyroxine-binding globulinTGAb = anti-thyroglobulin antibodiesTPOAb = anti-thyroperoxidase antibodiesTSH = thyroid-stimulating hormone     

Maternal Thyroid-Stimulating Hormone Level in the First Trimester and Sex Ratio at Birth

Objective: Few studies have explored the influence of thyroid status on sex ratio at birth, and conclusions are inconsistent. The aim of this study was to determine if there is an association between serum thyroid-stimulating hormone (TSH) level in first trimester and sex ratio at birth.Methods: The study was a retrospective cohort study performed at a tertiary care center. From March 2014 to February 2017, a total of 4,822 women who had thyroid function testing during the first trimester were included. Study population was divided into five groups according to quintile of TSH level (≤0.60 mIU/L; 0.61 to 1.02 mIU/L; 1.03 to 1.44 mIU/L; 1.45 to 2.13 mIU/L; and ≥2.14 mIU/L). Logistic regression analysis was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of the percentage of male infants across the quintiles, with the lowest quintile as the reference category.Results: Median level of TSH was 1.27 mIU/L in women who delivered a boy, which was significantly higher than that in women who delivered a girl (1.15 mIU/L). After adjusting for age, gravidity, and parity, multivariate logistic analysis found that women in quintiles 3, 4, and 5 all showed significantly higher ORs for delivering a boy than those in quintile 1. In addition, after adjusting for age, gravidity, and parity, serum TSH was significantly associated with likelihood of having a boy (OR, 1.08; 95% CI, 1.03 to 1.13).Conclusion: Maternal TSH level in the first trimester is positively associated with the probability of delivering a male newborn.Abbreviations: CI = confidence interval; FT3 = free triiodothyronine; FT4 = free thyroxine; OR = odd ratio; SRB = sex ratio at birth; TBG = thyroxin-binding globulin; TSH = thyroid-stimulating hormone     

Insulinoma in a Patient with Normal Results from Prolonged Fast and Glucagon-Induced Hypoglycemia

ObjectiveTo describe a man with a functioning insulinoma and normal results from two 72-hour fasts who developed hypoglycemia secondary to exaggerated insulin response following glucagon stimulation.MethodsWe report the patient’s clinical findings, laboratory findings, and clinical course. We also review the literature for previously reported cases and possible mechanisms.ResultsA 49-year-old man presented with hypoglycemic symptoms initially occurring after jogging and well-documented symptomatic hypoglycemia occurring during an evening meal. A 72-hour fast was associated with a serum glucose concentration of 50 mg/dL, suppressed insulin and C-peptide levels, and mildly elevated β-hydroxybutyrate. Another documented episode of hypoglycemia occurring 3 hours postprandially was associated with elevated insulin and C-peptide and suppressed β-hydroxybutyrate. A second 72-hour fast provoked asymptomatic hypoglycemia (glucose concentration at 60 hours: 32 mg/dL) with suppressed insulin and measurable β-hydroxybutyrate. After 72 hours of fasting, glucagon administration led to a decrease in glucose from 50 to 18 mg/dL, elevations in insulin and C-peptide, and suppression of β-hydroxybutyrate. Computed tomography revealed a mass lesion in the pancreatic tail. Distal pancreatectomy was performed, and the resected specimen demonstrated immunostaining for insulin. Hypoglycemic symptoms resolved postoperatively.ConclusionsNormal results from a prolonged fast do not preclude an insulinoma and may demonstrate exaggerated insulin secretion from the insulinoma following glucagon administration. In addition to examining the glucose response to glucagon as a surrogate for insulinoma diagnosis, measurement of serum insulin levels following glucagon administration may provide a further clue to the diagnosis of insulinoma. (Endocr Pract. 2010;16:838-841)     

Correlation of Increased Serum Adipsin with Increased Cardiovascular Risks in Adult Patients with Growth Hormone Deficiency

Objective: Adult growth hormone deficiency (AGHD) patients have an increased cardiovascular morbidity and mortality. Adipsin is an adipokine that is significantly correlated with metabolic disease, especially in people with obesity. The objective of our study was to compare AGHD patients with healthy subjects to evaluate whether adipsin levels are closely related to glycolipid metabolism and cardiovascular risks in AGHD patients.Methods: Our study included 88 AGHD patients and 88 age-, weight-, and body mass index (BMI)-matched healthy subjects. Anthropometric parameters such as BMI, waist circumference, and blood pressure were measured. Biochemical indicators such as serum adipsin, lipids, and fasting insulin levels were determined.Results: Adipsin levels in AGHD patients were significantly increased compared to levels of the control group (11,567.29 ng/mL, interquartile &lsqb;9,856.46 to 13,360.60 ng/mL]) versus (9,127.86 ng/mL, interquartile &lsqb;8,061.82 to 10,647.06 ng/mL], P = .000). Increased serum adipsin levels are correlated with cardiovascular risk factors such as a higher waist-to-hip ratio, serum lipids levels, and insulin resistance. Adipsin levels were inversely related to insulin-like growth factor 1 (IGF-1) (r = -0.6363, P<.0001) and insulin-like growth factor binding protein 3 levels (r = -0.498, P<.0001). The odds ratio (OR) for AGHD in the highest quartile was found to be 4.491 times the ratio in the lowest quartile (OR = 4.491, P = .048). Additionally, adipsin was found to be the most independent factor to influence IGF-1 levels in AGHD subjects.Conclusion: The serum levels of adipsin were significantly correlated with glucolipid metabolism disorder with a growth hormone deficiency status. Furthermore, serum levels of adipsin might be a good marker for the occurrence and development of cardiovascular diseases in AGHD patients.Abbreviations: AGHD = adult growth hormone deficiency; ASCVD = atherosclerotic cardiovascular disease; BMI = body mass index; DBP = diastolic blood pressure; FINS = fasting insulin; FPG = fasting plasma glucose; GH = growth hormone; HOMA-IR = homeostatic model to assess insulin resistance index; hsCRP = high-sensitivity C-reactive protein; IGF-1 = insulin-like growth factor 1; IGFBP-3 = insulin-like growth factor binding protein 3; LAP = lipid accumulation products; LDL = low-density lipoprotein; SBP = systolic blood pressure; TC = total cholesterol; TG = triglycerides; WC = waist circumference; WHR = waist-to-hip ratio; OR = odds ratio     

The Relationship Between Serum 25-Hydroxyvitamin D and Glucose Homeostasis in Obese Children and Adolescents in Zhejiang,China

Objective: Evidence of the association between vitamin D, insulin resistance, and oral disposition index (oDI) in obese children and adolescents is limited. To fill this research gap, we measured serum 25-hydroxyvitamin D (25&lsqb;OH]D) levels in obese children and analyzed the relationship between serum 25(OH)D levels and glucose homeostasis.Methods: Altogether, 348 obese and 445 nonobese children and adolescents (age, 6 to 16 years) were enrolled in this study. Obese children were divided into 4 subgroups: normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and combined IFG and IGT (IFG+IGT) according to oral glucose tolerance test results. We measured serum 25(OH)D levels and calculated the homeostasis model assessment (HOMA) of insulin resistance (IR), the whole-body insulin sensitivity index (WBISI), and the disposition index.Results: The levels of 25(OH)D in the obese group were significantly lower than in the nonobese group; serum 25(OH)D level in the NGT subgroup was higher than those of the other 3 subgroups, and it was significantly inversely correlated with logHOMA-IR (r = -0.090; P = .045) and positively correlated with logWBISI and logHOMA-oDI (r = 0.091, P = .049; and r = 0.108, P = .046, respectively). Obese patients with vitamin D deficiency thus have a significantly higher risk of disturbances in glucose metabolism.Conclusion: 25(OH)D deficiency or insufficiency is quite common in obese children and adolescents in Zhejiang, China. Obese patients with 25(OH)D deficiency (<30 nmol/L) are shown to be at higher risk for abnormal glucose metabolism.Abbreviations: 25(OH)D = 25-hydroxyvitamin D ΔI₃₀/ΔG₃₀ = insulinogenic index BMI = body mass index CI = confidence interval HbA_1c = hemoglobin A_1c HOMA = homeostasis model assessment I_F = fasting insulin IFG = impaired fasting glucose IGT = impaired glucose tolerance IR = insulin resistance NGT = normal glucose tolerance oDI = oral disposition index OGTT = oral glucose tolerance test WBISI = whole-body insulin sensitivity index     

Effect of Sitagliptin on Post-Prandial Glucagon and GLP-1 Levels in Patients With Type 1 Diabetes: Investigator-Initiated,Double-Blind,Randomized, Placebo-Controlled Trial

ObjectivePeripheral insulin resistance in type 1 diabetes may be related to a paradoxical postprandial glucagon increase. This study evaluated the effects of sitagliptin (dipeptidyl peptidase-IV [DPP-IV] inhibitor, approved for patients with type 2 diabetes), in adults with type 1 diabetes to improve glycemic control through decreasing postprandial glucagon.MethodsThis investigator-initiated, double-blind, randomized-parallel 20-week study enrolled 141 subjects. Subjects received sitagliptin 100 mg/day or placebo for 16 weeks. A subset of 85 patients wore blinded continuous glucose monitors (CGM) for 5 separate 7-day periods. The primary outcome was post-meal (Boost™) reduction in 4-hour glucagon area under the curve (AUC). Secondary endpoints included changes in glycated hemoglobin (A1c), CGM data, insulin dose, glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and C-peptide levels.ResultsThere were no differences at screening between groups; however, after a 4-week run-in phase, A1c was significantly lower in the sitagliptin vs. placebo group. Post-meal GLP-1 levels were higher (P<.001) and GIP levels lower (P = .03), with glucagon suppression at 30 minutes (LS means 23.2 ± 1.9 versus 16.0 ± 1.8; P = .006) in the sitagliptin group at 16 weeks. There were no differences between the groups in change in A1c, insulin dose, weight, or C-peptide after 16 weeks of treatment. However, C-peptide positive patients randomized to sitagliplin had a non-significant trend toward decrease in A1c, mean glucose, and time spent in hyperglycemia.ConclusionSitagliptin use in type 1 diabetes did not change glucagon AUC, A1c, insulin dose, or weight despite post-meal rise in GLP-1 levels. C-peptide positive subjects treated with sitagliptin had a nonsignificant trend in decreasing hyperglycemia, which needs further evaluation. (Endocr Pract. 2013;19:19-28)     

Technical Factors Involved in the Measurement of Circulating MicroRNA Biomarkers for the Detection of Colorectal Neoplasia

Background

Circulating miRNAs are emerging as promising blood-based biomarkers for colorectal and other human cancers; however, technical factors that confound the development of these assays remain poorly understood and present a clinical challenge. The aim of this study was to systematically evaluate the effects of factors that may interfere with the accurate measurement of circulating miRNAs for clinical purposes.

Methods

Blood samples from 53 subjects, including routinely drawn serum samples, matched plasma from 30 subjects, and matched serum samples drawn before and after bowel preparation for colonoscopy from 29 subjects were collected. Additionally, 38 serum specimens stored in the clinical laboratory for seven days were used to test the stability of miRNAs. Hemolysis controls with serial dilutions of hemoglobin were prepared. RNA was extracted from serum, plasma or hemolyzed controls with spiked-in cel-miR-39, and levels of miR-21, miR-29a, miR-125b and miR-16 were examined by real-time RT-PCR. Hemolysis was measured by spectrophotometry.

Results

The expression levels of miR-16 and the degree of hemolysis were significantly higher in plasma than in serum (P<0.0001). Measured miR-21, miR-29a, miR-125b and miR-16 expression increased with hemoglobin levels in hemolyzed controls. The degree of hemolysis in serum samples correlated significantly with the levels of miR-21 (P<0.0001), miR-29a (P = 0.0002), miR-125b (P<0.0001) and miR-16 (P<0.0001). All four miRNAs showed significantly lower levels in sera that had been stored at 4°C for seven days (P<0.0001). Levels of miR-21 (P<0.0001), miR-29a (P<0.0001) and miR-16 (P = 0.0003), and the degree of hemolysis (P = 0.0002) were significantly higher in sera drawn after vs. before bowel preparation.

Conclusions

The measured levels of miRNAs in serum and plasma from same patients varied in the presence of hemolysis, and since hemolysis and other factors affected miRNA expression, it is important to consider these confounders while developing miRNA-based diagnostic assays.     

C-Peptide and Beta-Cell Autoantibody Testing Prior to Initiating Continuous Subcutaneous Insulin Infusion Pump Therapy Did Not Improve Utilization Or Medical Costs Among Older Adults With Diabetes Mellitus

Objective: To study the impact of the C-peptide and beta-cell autoantibody testing required by the Center for Medicare and Medicaid Services (CMS) on costs/utilization for patients with diabetes mellitus initiating continuous subcutaneous insulin infusion (CSII) therapy.Methods: This retrospective study used propensity score–matched patients. Analysis 1 compared patients 1-year pre- and 2-years post-CSII adoption who met or did not meet CMS criteria. Analysis 2 compared Medicare Advantage patients using CSII or multiple daily injections (MDI) who did not meet CMS criteria for 1-year pre- and 1-year post-CSII adoption. Analysis 3 extended analysis 2 to 2 years postindex and also included a subset of patients ≥55 years old but not yet in Medicare Advantage.Results: Analysis 1 resulted in significantly slower growth in hospital admissions (P =.0453) in CSII-treated patients who did not meet the criteria. Analyses 2 and 3 showed numerically slower growth in inpatient, outpatient, and emergency department (ED) costs for CSII versus MDI patients (both not meeting criteria). Analysis 3 showed significantly slower growth in ED costs and hospital admissions for CSII versus MDI Medicare Advantage patients before propensity matching (both P<.05). In patients ≥55 years old, ED costs grew more slowly for CSII than MDI therapy (P =.0678).Conclusion: Numerically slower growth in hospital admissions was seen for pump adopters who did not meet CMS C-peptide criteria, while medical costs growth was similar. For CSII users who did not meet the CMS criteria, numerically slower growth in inpatient, outpatient, ED costs, and hospital admissions occurred versus MDI.Abbreviations: CMS = Center for Medicare and Medicaid Services; CSII = continuous subcutaneous insulin infusion; DM = diabetes mellitus; DME = durable medical equipment; ED = emergency department; MDI = multiple daily injections (of insulin)     

Differential Endocrine and Metabolic Effects of Testosterone Suppressive Agents in Transgender Women

Objective: Suppression of testosterone secretion and/or action in transgender women using cyproterone acetate (CPA), spironolactone, or gonadotropin-releasing hormone analogues (GA) is achieved through various mechanisms. Our objective was to characterize possible differential effects of these compounds on metabolic and endocrine variables.Methods: We conducted a historic cohort study of transgender patients treated in a tertiary referral center. A longitudinal analysis of treatment naïve patients and a cross-sectional analysis of the whole cohort at the last visit was carried out.Results: Among 126 transgender women (75 treatment-naïve), CPA was the predominant androgen suppressive therapy (70%), followed by spironolactone (17.6%), and GA (10.2%). Among those who were treatment-naïve, the increase in serum prolactin levels over baseline was greater at 3 months following CPA initiation (mean change 397 ± 335 mIU/L) than following spironolactone (20.1 ± 87 mIU/L) or GA initiation (64.6 ± 268 mIU/L; P = .0002). Prolactin levels remained higher in the CPA-treated group throughout follow-up, irrespective of estradiol levels, which were similar between the groups. A worse metabolic profile was associated with treatment with CPA than with spironolactone or GA. In the CPA compared to the spironolactone and GA groups, high-density lipoprotein-cholesterol levels were lower (47.1 ± 10.4, 54.4 ± 12.2, and 60.3 ± 13, respectively; P = .0076), while body mass index levels (24.3 ± 5, 21.7 ± 2.3, and 20.7 ± 3.1 kg/m²; P = .03), and systolic (117 ± 12.1, 109 ± 12.2, and 105 ± 13.3 mm Hg; P = .01) and diastolic (74 ± 9, 65.6 ± 5.5, and 65.4 ± 11 mm Hg; P = .0008) blood pressure levels were higher at the last visit.Conclusion: Treatment of transgender women with CPA was associated with hyperprolactinemia and a worse cardiovascular risk profile than treatment with spironolactone or GA.Abbreviations: BMI = body mass index; CPA = cyproterone acetate; E2 = estradiol; FSH = follicle-stimulating hormone; GA = gonadotropin-releasing hormone analogues; LH = luteinizing hormone     

Evaluation of Diabetes Management In A Rural Community Hospital

ObjectiveTo evaluate the effectiveness of implementing standardized insulin protocols in a small, rural community hospital.MethodsThis retrospective review was performed on charts of 300 inpatients who received insulin treatment while hospitalized between January 1, 2006, and June 30, 2006. For patients who met the inclusion criteria, the collected information included the following: serum glucose level at hospital admission, glucose level that initiated the treatment protocol, time-to-fasting euglycemia, time-to-random euglycemia, and method of insulin administration. Comparisons were performed between the effectiveness of the new insulin protocols and routine insulin treatment orders.ResultsA total of 168 patients met the study inclusion criteria. The mean glucose concentration that triggered initiation of insulin treatment was 262 mg/dL, which is significantly higher (P < .001) than levels recommended by the American Diabetes Association (ADA) and the American College of Endocrinology (ACE). There was a statistically significant relationship (P = .007) between time-to-fasting euglycemia and length of hospital stay. Implementation of the standardized insulin protocol did not improve the achievement of fasting euglycemia (P = .753). Most patients never reached the target glucose level goals despite the use of standardized protocol.ConclusionSignificant delays in initiating the insulin protocol and frequent failure in achieving target glucose levels demonstrate delayed recognition of hyperglycemia by hospital staff as well as ineffective use of standardized insulin protocols. Protocol improvement and increased hospital staff education concerning appropriate hospital target glucose levels are required to achieve ADA/ACE recommendations in small community hospitals. (Endocr Pract. 2008;14:50-57)     

Hyperthyroidism and Hyperprolactinemia: Is There any Association?

Objective: To compare the serum prolactin level in hyperthyroid and normal control females. Hyperthyroidism is a common disease. Although a direct association has been demonstrated between hypothyroidism and increased prolactin levels, this association has not been established for hyperthyroidism.Methods: Cross-sectional study in cases and control groups. Control subjects were chosen from those participating in the Kerman Coronary Artery Disease Risk Factors study. To select the cases, all women referred to the laboratories of Kerman with a thyroid-stimulating hormone (TSH) level ≤0.5 mIU/L who met the inclusion criteria were entered in the study. A total of 231 women aged 15 to 50 years were enrolled. The case group included 71 hyperthyroid women, and the control group included 160 women with normal thyroid function matched by age.Results: The mean (SD) serum level of prolactin was 16.56 (0.97) ng/mL (95% confidence interval [CI], 15.41 ng/mL to 15.71 ng/mL) in the controls and 23.07 (1.49) ng/mL (95% CI, 22.7 ng/mL to 23.4 ng/mL) in the case subjects. Hyperprolactinemia was more common in the hyperthyroid group (16.5 [0.97] ng/mL versus 23.07 [1.49] ng/mL; P<.001). The prolactin level decreased with age. Hyperthyroidism and estradiol increased the prolactin level. After adjusting for age and estradiol, hyperthyroidism increased the serum prolactin level (P<.001).Conclusion: The results of this study revealed that hyperprolactinemia is more frequent in hyperthyroid females. Serum prolactin level can be increased in hyperthyroidism.Abbreviations:PRL = prolactinT4 = thyroxineTRH = thyrotropin-releasing hormoneTSH = thyroid-stimulating hormone     

Pilot Study to Evaluate the Effect of Short-Term Improvement in Vitamin D Status on Glucose Tolerance in Patients With Type 2 Diabetes Mellitus

ObjectiveTo study the effect of improvement in vitamin D status on glucose tolerance in Asian Indian patients with moderately controlled type 2 diabetes mellitus (T2DM).MethodsThis randomized, double-blind, placebocontrolled pilot study was conducted in 28 Asian Indian patients with T2DM. Study participants were randomly assigned to a vitamin D-treated group (group D) or a placebo group (group P). Serum 25-hydroxyvitamin D, hemoglobin A1c, and serum fructosamine levels were measured, and an oral glucose tolerance test (OGTT) was performed in all patients at baseline and 4 weeks after intervention. During the OGTT, plasma glucose and serum insulin levels were measured at 0, 30, 60, 90, and 120 minutes. The unpaired t test was used to compare the groups at baseline and to compare the differences in changes from baseline to 4 weeks between the 2 study groups.ResultsGroup D and group P were similar with respect to their fasting plasma glucose and serum insulin concentrations, post-OGTT plasma glucose and serum insulin levels, and hemoglobin A1c and fructosamine values at baseline. Serum 25-hydroxyvitamin D levels increased significantly in group D at 4 weeks. No significant differences were found between the groups at baseline and 4 weeks with respect to serum fructosamine, fasting plasma glucose and serum insulin, post-OGTT plasma glucose and serum insulin levels, and homeostasis model assessment of insulin resistance.ConclusionIn this study, short-term improvement in vitamin D status was not associated with improvement in glucose tolerance, insulin secretion, or insulin sensitivity in Asian Indian patients with moderately controlled T2DM.(Endocr Pract. 2010;16:600-608)     

Effect of Dexamethasone on Oral Glucose Tolerance in Healthy Adults

ObjectiveTo determine the dose-response and time course of action of a single dose of dexamethasone on plasma glucose and insulin dynamics in healthy adults.MethodsParticipants included healthy adults who met the following inclusion criteria: 18 to 65 years of age, body mass index of 18 to 25 kg/m2, no family history of diabetes mellitus, not taking any medication known to affect glucose tolerance, and nonpregnant state for female participants. Each participant underwent 3 sequential blocks of 75-g oral glucose tolerance tests (OGTTs) on days 1, 2, and 3; this sequence was repeated on 3 different occasions separated by more than 2 weeks. On the first day of each block, participants reported to the research center after a 10- to 12-hour overnight fast, and fasting baseline blood samples for glucose, insulin, and C-peptide were obtained. Baseline (0 mg) OGTT was then performed with a 75-g glucose load, and blood samples were collected at 30, 60, 90, and 120 minutes for measurements of glucose, insulin, and C-peptide. After the baseline OGTT on day 1, a single dose of either 2-, 4- or 8-mg of dexamethasone was administered orally. Twenty-four and 48 hours later, participants returned for additional OGTTs.ResultsTen healthy volunteers (4 male and 6 female) were enrolled. The effect of dexamethasone was maximal 24 hours after 8-mg dexamethasone compared with the effect observed after no dexamethasone administration. At 60 minutes during the OGTT (following 8-mg dexamethasone), blood glucose increased from 127 ± 7.1 mg/dL (6.35 ± 0.36 mmol/L) to 176 ± 19 mg/dL (8.8 ± 0.95 mmol/L), insulin increased from 49.3 ± 3.2 μIU/mL (342 ± 22 pmol/L) to 119.7 ± 10.1 μIU/mL (831 ± 70 pmol/L), and C-peptide increased from 6376 ± 510 pg/L (1913 ± 153 pmol/L) to 10 143 ± 1016 pg/L (3043 ± 305 pmol/L); the 60-minute levels returned towards baseline at 48 hours. Smaller changes were observed with 2- and 4-mg dexamethasone. Twenty-four hours after 8-mg dexamethasone, there was a 2.2- and 1.5-fold increase in homeostasis model assessment of insulin resistance and homeostasis model assessment of β cell, respectively, and a 2.5-fold decrease in the Matsuda sensitivity index.ConclusionsA single oral dose of 8-mg dexamethasone increases blood glucose, insulin, and C-peptide levels maximally at 24 hours, 1 hour following 75-g OGTT. A dexamethasone stress test might identify persons at increased risk for type 2 diabetes. (Endocr Pract. 2010:16:770-777)     

Comparison of Methodologies to Detect Low Levels of Hemolysis in Serum for Accurate Assessment of Serum microRNAs

microRNAs have emerged as powerful regulators of many biological processes, and their expression in many cancer tissues has been shown to correlate with clinical parameters such as cancer type and prognosis. Present in a variety of biological fluids, microRNAs have been described as a ‘gold mine’ of potential noninvasive biomarkers. Release of microRNA content of blood cells upon hemolysis dramatically alters the microRNA profile in blood, potentially affecting levels of a significant number of proposed biomarker microRNAs and, consequently, accuracy of serum or plasma-based tests. Several methods to detect low levels of hemolysis have been proposed; however, a direct comparison assessing their sensitivities is currently lacking. In this study, we evaluated the sensitivities of four methods to detect hemolysis in serum (listed in the order of sensitivity): measurement of hemoglobin using a Coulter® AcT diff™ Analyzer, visual inspection, the absorbance of hemoglobin measured by spectrophotometry at 414 nm and the ratio of red blood cell-enriched miR-451a to the reference microRNA miR-23a-3p. The miR ratio detected hemolysis down to approximately 0.001%, whereas the Coulter® AcT diff™ Analyzer was unable to detect hemolysis lower than 1%. The spectrophotometric method could detect down to 0.004% hemolysis, and correlated with the miR ratio. Analysis of hemolysis in a cohort of 86 serum samples from cancer patients and healthy controls showed that 31 of 86 (36%) were predicted by the miR ratio to be hemolyzed, whereas only 8 of these samples (9%) showed visible pink discoloration. Using receiver operator characteristic (ROC) analyses, we identified absorbance cutoffs of 0.072 and 0.3 that could identify samples with low and high levels of hemolysis, respectively. Overall, this study will assist researchers in the selection of appropriate methodologies to test for hemolysis in serum samples prior to quantifying expression of microRNAs.     

The Impact of Age in the Management of Hypothyroidism: Results of a Nationwide Survey

Objective: Evidence exists that thyroid-stimulating hormone (TSH) increases with age and lowering the TSH goal in older patients on thyroid hormone may cause over-treatment. Risks of overtreatment include cardiac and skeletal events. We assessed practice patterns regarding TSH goals and explored factors influencing physicians' decision making when managing hypothyroidism.Methods: Members of the American College of Physicians, the American Academy of Family Practice, and the Endocrine Society were surveyed to determine goal TSH when treating hypothyroidism.Results: Fifty-three percent of physicians reported factoring patient age into their decision making when managing hypothyroidism. Patient age was prioritized third (53%), following patient symptoms (69.2%) and cardiac arrhythmias (65.7%). In multivariable analysis, endocrinologists (P = .002), internists (P = .049), physicians in academic settings (P = .003), and high-volume physicians (P = .021) were more likely to consider patient age when determining goal TSH. When presented with scenarios differing in patient gender and age, 90% of physicians targeted a TSH ≤3.0 mIU/L in 30-year-old patients. Fifty-three percent of respondents targeted a TSH ≤3.0 mIU/L in octogenarians, but 90% targeted a TSH >1.5 mIU/L in this group. Regardless of gender, physician-reported TSH goal ranges (0.1 to 0.5, 0.6 to 1.5, 1.6 to 3.0, and 3.1 to 5.0 mIU/L) increased in a direct relationship to patient age (P<.001).Conclusion: Just over half of physicians consider patient age when determining TSH goal. When presented with scenarios differing in patient age and gender, physicians targeted a higher TSH goal in octogenarians. This may indicate an attempt to avoid overtreatment in this group. Consensus is needed among physicians regarding the role of patient age in hypothyroidism management.Abbreviations:TSH = thyroid-stimulating hormone     

Ketosis-Prone Type 2 Diabetes: Effect of Hyperglycemia on β-Cell Function and Skeletal Muscle Insulin Signaling

ObjectiveTo determine the underlying mechanism for the severe and transient β-cell dysfunction and impaired insulin action in obese African American patients with ketosis-prone diabetes.MethodsThe effect of sustained hyperglycemia (glucotoxicity) and increased free fatty acids (lipotoxicity) on β-cell function was assessed by changes in insulin secretion during a 20-hour glucose (200 mg/m² per minute) and a 48-hour Intralipid (40 mL/h) infusion, respectively. Insulin-activated signaling pathways and pattern of Akt-1 and Akt-2 expression and insulin-stimulated phosphorylation were analyzed in skeletal muscle biopsy specimens. Studies were performed in an obese African American woman within 48 hours after resolution of diabetic ketoacidosis and 1 week after discontinuation of insulin treatment.ResultsDextrose infusion rapidly increased C-pep-tide levels from a baseline of 3.2 ng/mL to a mean of 7.1 ± 0.5 ng/mL during the first 8 hours of infusion; thereafter, C-peptide levels progressively declined. Lipid infusion was not associated with any deleterious effect on insulin and C-peptide secretion. Initial in vitro stimulation of muscle tissue with insulin resulted in a substantial and selectively decreased Akt-2 expression and insulin-stimulated phosphorylation on the serine residue. Improved metabolic control resulted in 70% greater Akt expression at near-normoglycemic remission in comparison with the period of hyperglycemia.ConclusionHyperglycemia, but not increased free fatty acid levels, led to progressive β-cell dysfunction and impaired insulin secretion. Hyperglycemia was also associated with diminished skeletal muscle Akt expression and phosphorylation in an African American woman with ketosis-prone diabetes, and this defect improved notably with aggressive insulin therapy. These results indicate the importance of glucose toxicity in the pathogenesis of keto-sis-prone diabetes in obese African American patients. (Endocr Pract. 2007;13:283-290)     

Thyroid Function and Metabolic Syndrome: A Cross-Sectional Study in Obese and Overweight Patients

Objective: Metabolic syndrome (MetS) is associated with increased risks of developing cardiovascular disease and type 2 diabetes. Thyroid dysfunction is also a known cardiovascular risk factor. In obese patients, serum thyroid-stimulating hormone (TSH) levels tend to be higher than in lean controls. The objective of this study was to assess potential associations between serum TSH levels and MetS as well as individual components of MetS.Methods: This was a cross-sectional observational study of obese and overweight patients seen for initial evaluation at the Boston Medical Center weight-management clinic between February 1, 2013 and February 1, 2014. Demographic, anthropometric, and laboratory data including serum TSH, insulin, glucose, hemoglobin A_1c, and lipid levels were obtained from electronic medical records. Associations between serum TSH levels and presence of MetS and its components were assessed.Results: A total of 3,447 patients, 75.6% female and 38% African American, without known thyroid dysfunction, were included. Mean ± SD age was 46.74 ± 15.11 years, and mean ± SD body mass index was 36.06 ± 9.89 kg/m². Among 1,005 patients without missing data, the prevalence of MetS was 71.84%. In patients with MetS, the median serum TSH was 1.41 μIU/mL, compared with 1.36 μIU/mL in patients without MetS (P = .45). In multivariate models, there was no significant association between serum TSH levels and the presence of MetS, adjusting for age, sex, race, education, socioeconomic status, and smoking. There were also no significant associations between serum TSH and individual components of the MetS.Conclusion: Serum TSH level does not appear to be a potentially modifiable risk factor for MetS in obese and overweight individuals.Abbreviations: BMI = body mass index FT₄ = free thyroxine HDL-C = high-density-lipoprotein cholesterol HbA_1c = hemoglobin A_1c MetS = metabolic syndrome SE = standard error TSH = thyroid-stimulating hormone     

Impact of Ramadan Fasting on Thyroid Status and Quality of Life in Patients with Primary Hypothyroidism: a Prospective Cohort Study from karachi,pakistan

Objective: Ramadan is the ninth month in the lunar calendar, during which Muslims fast from predawn to sunset and major changes occur in their dietary, sleep, and physical activity patterns. Most patients with hypothyroidism are unable to comply with the proper timings of levothyroxine (LT4) administration. The objective of the study was to determine the change in thyroid-stimulating hormone (TSH) level and quality of life (QOL) before and after Ramadan in patients with primary hypothyroidism.Methods: This prospective cohort study included adult patients on stable doses of LT4 who fasted for at least 20 days during the month of Ramadan in the Islamic year 1437 Hijri (June/July 2016). Baseline characteristics and TSH levels were recorded on all consenting patients within 6 weeks prior to Ramadan. Post-Ramadan TSH was tested within 1 to 2 weeks after Eid-ul-Fitr.Results: During the study period, 64 patients with hypothyroidism were enrolled, of which 58 were female. The mean age of participants was 44.2 ± 13.2 years. Average daily dose of LT4 was 95.3 ± 35.4 μg. On average, patients fasted for 26.5 days and missed a dose of LT4 on 1.27 days. Mean TSH pre-Ramadan was 2.37 ± 1.35 mIU/L, and post-Ramadan, it was 4.69 ± 3.87 mIU/L. Mean difference between TSH pre- and post-Ramadan was 2.32 ± 3.80 mIU/L (P<.001). However, the difference in TSH was not significantly different between those who were compliant with meals and LT4 interval versus those who were not (compliant, 2.04 mIU/L; noncompliant, 3.15 mIU/L; P = .30). Overall, an increase in QOL scores in the domains of physical health, psychological health, and social relationships was observed after Ramadan.Conclusion: We observed statistically significant changes in TSH concentrations after the month of Ramadan in hypothyroid patients who fasted. The change in TSH was not affected by timing of LT4 intake and interval from meal.Abbreviations: AKUH = Aga Khan University Hospital; LT4 = levothyroxine; QOL = quality of life; TSH = thyroid-stimulating hormone