Naloxone stimulation of luteinizing hormone secretion in the female monkey: influence of endocrine and experimental conditions

It is known that opiate administration results in the inhibition of LH release. In this paper, we examine the role of endogenous opiates in the regulation of gonadotropin secretion during the menstrual cycle of the monkey. The objectives of these experiments were to determine the experimental and endocrine conditions that are conducive to increased gonadotropin secretion in response to endogenous opiate antagonism. In Exp 1, naloxone was administered during the luteal phase to three groups of monkeys under three different experimental conditions. When naloxone (2 mg, iv) was injected into conscious unrestrained or sedated animals, LH secretion increased 2- to 3-fold. In contrast, the same dose of naloxone failed to stimulate LH secretion in monkeys restrained in primate chairs. In Exp 2, the gonadotropin response to acute naloxone administration on each day of the menstrual cycle was determined. A significant increase in the serum LH concentration (greater than or equal to 20% within 40 min of injection) was observed after naloxone administration in 60% of the trials conducted during the luteal phase. Significant increases occurred in only 13% of the saline-treated control trials during this stage of the menstrual cycle. Mean LH levels increased from 14.4 +/- 1.3 to 31.2 +/- 4.3 ng/ml after naloxone injection. In contrast, naloxone had no effect on LH secretion during the follicular phase. Although small LH increments were noted after naloxone injection in 40 +/- 8% of the trials, neither the frequency nor the amplitude of these increases was different from that in follicular phase controls. We conclude from these results that the ability of naloxone to stimulate LH secretion is limited to the luteal phase. Previous findings from our laboratory indicate that hypothalamic beta-endorphin activity, as reflected by its concentration in hypophyseal portal blood, is increased by ovarian steroids and that its greatest activity occurs during the luteal phase. Since the response of LH to naloxone administration was limited to the luteal phase, we believe that these results support the conclusion that hypothalamic beta-endorphin is a physiological modulator of LH secretion in the monkey.

Colesevelam Hydrochloride-Ezetimibe Combination Lipid-Lowering Therapy in Patients with Diabetes or Metabolic Syndrome and a History of Statin Intolerance

OBJECTIVE

To determine the effectiveness and safety of colesevelam hydrochloride (HCl) and ezetimibe combination therapy in statin-intolerant patients with dyslipidemia and diabetes mellitus (DM) or metabolic syndrome (MS).

METHODS

We identified potential study subjects through a computerized text search of patient electronic medical records using the terms colesevelam, WelChol, ezetimibe, and Zetia. Medical records were subsequently reviewed to identify all patients with DM or MS. Baseline total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, and triglyceride levels immediately before the initiation of therapy with colesevelam HCl (1.875 g twice a day) or ezetimibe (10 mg daily) were compared with those after a minimum of 3 months of single drug therapy and after a minimum of 3 months of combination therapy. Drug safety was evaluated by review of transaminase levels and reports of side effects or drug discontinuation.

RESULTS

The computerized search initially identified 91 electronic medical records; 16 patients fulfilled all study criteria. Baseline patient demographics included a mean age of 62.5 (+/-11.8) years and a mean body mass index of 31.4 (+/-5.2) kg/m2; 50% of patients were female, 75% had type 2 DM, and 25% had MS. In comparison with baseline, colesevelam HCl-ezetimibe combination therapy was associated with significant reductions in mean levels of total cholesterol (27.5%), LDL-C (42.2%), and non-HDL-C (37.1%). In addition, 50% of patients achieved the National Cholesterol Education Program Adult Treatment Panel III LDL-C target of less than 100 mg/dL. Therapy was well tolerated, with no significant changes in mean transaminase levels, no reports of myalgia, and no discontinuation of therapy.

CONCLUSION

Colesevelam HCl-ezetimibe combination therapy was associated with improved TC, LDL-C, and non-HDL-C lipid profiles and was well tolerated. Such therapy may be a reasonable consideration for statin-intolerant patients with DM or MS who have elevated cholesterol levels.

A glucose meter accuracy and precision comparison: the FreeStyle Flash Versus the Accu-Chek Advantage, Accu-Chek Compact Plus, Ascensia Contour, and the BD Logic

BACKGROUND

This study compared the accuracy and precision of five blood glucose (BG) meters.

METHODS

Diabetes patients undergoing venipuncture for glucose testing were randomized to one of two groups consisting of three meters: FreeStyle Flash (Abbott Diabetes Care, Alameda, CA), Accu-Chek Advantage (Roche Diagnostics Corp., Indianapolis, IN), and Accu-Chek Compact Plus (Roche Diagnostics) or FreeStyle Flash, Ascensia Contour (Bayer Healthcare, Diagnostic Division, Tarrytown, NY), and BD Logic (BD Diabetes Care, Franklin Lake, NJ). Within 5 min following venipuncture, duplicate finger BG measurements from three ipsilateral fingers were taken. Finger glucose measurements were compared with laboratory reference values. Accuracy was assessed by a Clarke error grid analysis (EGA) and within 10% of the laboratory value criteria. Meter precision was determined by calculating the absolute mean differences in glucose values between duplicate samples.

RESULTS

Finger sticks were obtained from 202 patients. Mean venipuncture BG was 148 mg/dL (SD +/- mg/64 dL; range 25-439 mg/dL). Accuracy by Clarke EGA (Zone A results) was demonstrated in 69% of Advantage samples, 75% of Compact Plus, and 96% of the first group of Flash versus 88% of the Contour, 67% of the Logic, and 91% of the second Flash samples (P < 0.05 for both Flash and Contour). Meter accuracy using the 10% criteria was demonstrated in 30%, 38%, 70%, 46%, 48%, and 68% of the samples, respectively (P < 0.05 for both Flash groups compared to each of the other meters). There were no differences in meter precision.

CONCLUSIONS

No statistically significant differences in accuracy were evident using the Clarke EGA criteria (pooled results of Zone A and B), though the more strict 20% accuracy criteria (Zone A results only) found the Flash and Contour to have significantly greater accuracy compared to the Advantage, Compact Plus, and the Logic. Using the 10% accuracy criteria found the Flash to have significantly greater accuracy than each of the other four meters. All five meters demonstrated similar precision.

Cholesterol and glycemic effects of Niaspan in patients with type 2 diabetes

STUDY OBJECTIVE

To determine the effect of Niaspan--a niacin preparation with both immediate- and extended-release characteristics--on lipid and glycemic control in patients with type 2 diabetes.

DESIGN

Retrospective study

SETTING

Private-practice endocrinology group.

PATIENTS

Thirty-two patients (mean age 60 yrs; 72% men) with type 2 diabetes identified by a computerized text search.

INTERVENTION

Patients received Niaspan 1000, 1500, or 2000 mg/day (median daily dosage 1000 mg).

MEASUREMENTS AND MAIN RESULTS

Total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, hemoglobin A1c, and transaminase levels were compared for each patient before and 6 months after initiation of Niaspan. Niaspan therapy was associated with a significant 34% increase in HDL (p=0.033), a significant 36% reduction of triglycerides (p=0.049), and no significant change in LDL (p=0.236) or total cholesterol (p=0.122). Mean hemoglobin A1c levels significantly decreased from baseline by 0.5 +/- 0.3% (p=0.032), even though dosages and treatment with antidiabetic agents remained constant. There were no significant changes in transaminase levels. Seven patients (21.9%) discontinued Niaspan; one of them experienced an increase in blood glucose while receiving the agent.

CONCLUSION

For most patients with type 2 diabetes, Niaspan is a safe and effective therapy for dyslipidemia and does not exacerbate glycemic control.

Accuracy of home blood glucose monitors using forearm blood samples: FreeStyle versus One Touch Ultra

The accuracy of two home blood glucose monitors using forearm blood samples was studied. Blood samples were obtained from adults by venipuncture and analyzed for glucose concentration. Within five minutes after venipuncture, peripheral blood glucose measurements were taken in duplicate with the FreeStyle and One Touch Ultra monitors by using the same forearm as used for venipuncture. Accuracy was assessed by comparing the results for each first peripheral stick obtained by each monitor with the laboratory reference value. Monitor precision was evaluated by evaluating the mean difference in glucose values between the first and second peripheral sticks. Blood samples were obtained from 250 subjects, 170 (68%) of whom had diabetes mellitus. A total of 98.8% and 98.4% of the blood glucose readings obtained with FreeStyle and One Touch Ultra, respectively, were clinically acceptable, and 65.2% and 59.2% of the measurements, respectively, were within 10% of the laboratory reference values. The average difference between the first and second glucose measurements was 9.7 mg/dL for FreeStyle and 5.2 mg/dL for One Touch Ultra. One peripheral stick was needed to obtain an adequate blood sample in 95.6% of subjects using FreeStyle, compared with 83.2% of subjects using One Touch Ultra. Forearm blood glucose measurements obtained with the FreeStyle and One Touch Ultra devices were similar to laboratory reference values obtained by venipuncture.

Precision and accuracy of two blood glucose meters: FreeStyle Flash versus One Touch Ultra

PURPOSE

The precision and accuracy of two blood glucose meters were evaluated using finger and forearm blood samples.

METHODS

Duplicate blood glucose measurements on the same forearm and finger as venipuncture were performed with the FreeStyle Flash and the One Touch Ultra. Accuracy was assessed by error-grid analysis and the number of values within 10% of the laboratory reference value. Precision was determined by calculating the absolute mean percent differences in glucose values between the first and second fingers and forearm test results. Forearm testing success was defined as an accurate glucose reading obtained with one lance.

RESULTS

A total of 100 patients completed the study; 93% had diabetes and 53% were female. Patients' mean +/- S.D. age was 63 +/- 12 years, and glucose measurements ranged from 69 to 354 mg/dL. All finger-stick samples fell within error-grid zones A and B; 72% and 57% of FreeStyle Flash and One Touch Ultra values fell within 10% of the laboratory reference values, respectively (p = 0.027). Forearm samples were successfully obtained in 99 and 74 patients using the FreeStyle Flash and One Touch Ultra (p < 0.001), with 64 and 36 samples, respectively, falling within 10% of the laboratory reference values (p = 0.035). There was no difference in meter precision.

CONCLUSION

The FreeStyle Flash and the One Touch Ultra are precise glucose meters; however, the FreeStyle Flash was associated with greater accuracy. Success rates of forearm glucose sampling were significantly greater when the FreeStyle Flash meter was used.

Accuracy and precision of four value-added blood glucose meters: the Abbott Optium, the DDI Prodigy, the HDI True Track, and the HypoGuard Assure Pro

PURPOSE

This study compared the accuracy and precision of four value-added glucose meters.

METHODS

Finger stick glucose measurements in diabetes patients were performed using the Abbott Diabetes Care (Alameda, CA) Optium, Diagnostic Devices, Inc. (Miami, FL) DDI Prodigy, Home Diagnostics, Inc. (Fort Lauderdale, FL) HDI True Track Smart System, and Arkray, USA (Minneapolis, MN) HypoGuard Assure Pro. Finger glucose measurements were compared with laboratory reference results. Accuracy was assessed by a Clarke error grid analysis (EGA), a Parkes EGA, and within 5%, 10%, 15%, and 20% of the laboratory value criteria (chi2 analysis). Meter precision was determined by calculating absolute mean differences in glucose values between duplicate samples (Kruskal-Wallis test).

RESULTS

Finger sticks were obtained from 125 diabetes patients, of which 90.4% were Caucasian, 51.2% were female, 83.2% had type 2 diabetes, and average age of 59 years (SD 14 years). Mean venipuncture blood glucose was 151 mg/dL (SD +/-65 mg/dL; range, 58-474 mg/dL). Clinical accuracy by Clarke EGA was demonstrated in 94% of Optium, 82% of Prodigy, 61% of True Track, and 77% of the Assure Pro samples (P < 0.05 for Optium and True Track compared to all others). By Parkes EGA, the True Track was significantly less accurate than the other meters. Within 5% accuracy was achieved in 34%, 24%, 29%, and 13%, respectively (P < 0.05 for Optium, Prodigy, and Assure Pro compared to True Track). Within 10% accuracy was significantly greater for the Optium, Prodigy, and Assure Pro compared to True Track. Significantly more Optium results demonstrated within 15% and 20% accuracy compared to the other meter systems. The HDI True Track was significantly less precise than the other meter systems.

CONCLUSIONS

The Abbott Optium was significantly more accurate than the other meter systems, whereas the HDI True Track was significantly less accurate and less precise compared to the other meter systems.

The utility of insulin glargine in the treatment of diabetes mellitus

STUDY OBJECTIVES

To compare hemoglobin A1c (A1C) values at baseline with those after 1 year of insulin glargine therapy and, secondarily, to compare insulin dosage and patients' body weight at baseline and at 1 year.

DESIGN

Retrospective study.

SETTING

Private endocrinology practice.

PATIENTS

One hundred ninety-seven patients with diabetes mellitus who were first prescribed insulin glargine from May 2001-April 2002 and were evaluable after 1 year of therapy

INTERVENTION

Patients received insulin glargine instead of NPH insulin or in addition to their oral drug therapy

MEASUREMENTS AND MAIN RESULTS

Patients with diabetes type 1 (receiving insulin therapy) or type 2 (receiving oral drug therapy only, a combination of oral drug therapy and insulin, or insulin only) who had been treated with insulin glargine for 1 year were evaluated. Overall, A1C values decreased significantly (p<0.001) by 0.53 +/- 1.4% from a baseline mean of 8.1 +/- 1.7%. In 129 patients with type 2 diabetes previously treated with NPH insulin, A1C decreased significantly (p<0.001) 0.57 +/- 1.5% from baseline. The A1C decreased by 0.71 +/- 1.3% (p=0.0043) from baseline in 33 patients with type 2 diabetes who previously received oral agents only Thirty-five patients with type 1 diabetes demonstrated no significant change in A1C (-0.22 +/- 1.0%, p=0.217) from baseline. In patients receiving insulin at baseline, the number of daily injections increased significantly (p<0.0001) from a median of two at baseline to three at 1 year. Overall, no significant change was noted in total daily insulin requirement or in body weight in any of the patient groups over the 1-year period.

CONCLUSION

Compared with baseline, insulin glargine therapy at 1 year was associated with an overall significant reduction in A1C of 0.53 +/- 1.4%.

Substitution of Pioglitazone for Troglitazone in Patients with Type 2 Diabetes

OBJECTIVE

To evaluate the clinical utility of pioglitazone therapy in patients who previously received troglitazone.

METHODS

We undertook an observational study involving patients with type 2 diabetes, who were originally treated with troglitazone and subsequently converted to pioglitazone therapy. Drug efficacy was evaluated by comparing baseline hemoglobin A1c (HbA1c) levels, weight, blood pressure, and lipid profiles (during troglitazone treatment) with corresponding values 6 months after final pioglitazone dose titration. Drug safety was evaluated by review of hepatic enzyme levels and documented reports of side effects.

RESULTS

The study cohort consisted of 316 patients in whom pioglitazone therapy was initiated after they had received troglitazone for at least 1 year. Discontinuation of pioglitazone treatment subsequently occurred in 43 patients; in 7 additional patients, no follow-up occurred. We found no significant difference between baseline and follow-up mean HbA1c values. Aspartate aminotransferase levels did not significantly change after 6 months of pioglitazone therapy; however, alanine aminotransferase levels increased by a statistically significant 3.8 U/L (95% confidence interval, 2.6 to 4.9). Pioglitazone treatment was discontinued because of edema in 29 of the 309 evaluable patients (9.4%).

CONCLUSION

Pioglitazone was as effective as troglitazone in maintaining HbA1c levels. The hepatic safety of pioglitazone was also demonstrated.

A pharmacist-run anabolic osteoporosis clinic: An abaloparatide descriptive report

OBJECTIVES

To review the first-year experience of abaloparatide use in a pharmacist-run anabolic osteoporosis clinic.

SETTING

This ambulatory-care health system endocrinology practice consists of 10 board-certified endocrinologists and 6 nurse practitioners and physician assistants. Approximately 1200 patients are seen weekly. The practice is affiliated with the Albany College of Pharmacy and Health Sciences and hosts 2 clinical pharmacy faculty members and a PGY-2 endocrinology pharmacy resident. A pharmacist-run teriparatide clinic was implemented in 2002. In 2017, the clinic was expanded to accept referrals for abaloparatide. No description of a pharmacist-run abaloparatide clinic has yet been reported.

PRACTICE DESCRIPTION

Patients are referred to a clinical pharmacist for initiation and education of anabolic osteoporosis therapy. The pharmacist is responsible for assessing for contraindications to anabolic therapy, securing managed care coverage of an anabolic agent, and providing medication counseling. This pharmacist is available as a resource to patients throughout their course of anabolic osteoporosis therapy.

PRACTICE INNOVATION

This is the first description of a pharmacist-run abaloparatide clinic.

EVALUATION

Not applicable.

RESULTS

During its first year of availability, 52 patients were referred for abaloparatide therapy. Of these, 31 patients (59.6%) initiated treatment. The population predominately consisted of postmenopausal white women. Approximately two-thirds of patients had a history of an osteoporosis-related fracture, and half of patients had previously received antiresorptive therapy for osteoporosis. Mean baseline T-scores for the lumbar spine and femoral neck were -2.41 and -2.57, respectively. Twenty-one patients did not initiate abaloparatide therapy owing to cost (9), concerns of therapy (8), or contraindication to therapy (4). An additional 5 patients discontinued abaloparatide therapy owing to adverse effects.

CONCLUSION

This paper reviews the first-year experience of abaloparatide use in a pharmacist-run anabolic osteoporosis clinic. The fact that only 60% of referred patients initiated therapy indicates that significant barriers (e.g., high patient cost and safety concerns) remain.

Weekly Exenatide Therapy

Background: Traditional diabetes therapies have been associated with weight gain, hypoglycemia, and/or high secondary failure rates. Glucagon-like peptide-1 (GLP-1) analog use is associated with a minimal risk of hypoglycemia, a persistent average weight loss of 2 to 3 kg, and sustained efficacy even after 3 years of use. Presently, 3 GLP-1 analogs are commercially available in the United States. Objective: To evaluate the real-world clinical utility of once weekly exenatide in type 2 diabetes mellitus (T2DM) patients who previously received once or twice daily GLP-1 therapy. Methods: In this pre–post observational study, electronic medical records (EMRs) were reviewed to identify patients meeting all study criteria. Data collected included baseline patient demographic information, duration of diabetes, disease states, medications, pertinent laboratory data, blood pressure, height, weight, and reported adverse drug events. Primary (changes in A1C and percentage of patients reporting adverse effects of therapy) and secondary (percentage of patients with A1C of <7% and changes in weight, blood pressure, and lipids) outcomes were evaluated using appropriate statistical analysis. Results: EMRs of 78 patients met all study criteria. Baseline patient demographic information included an average age of 61 ± 12 years, an average duration of T2DM of 14 ± 6 years, 59% of patients were male, and 93.6% were Caucasian. The baseline average body mass index was 39 ± 9.2, and mean A1C was 7.47 ± 1.45%. After a minimum of 3 months (average = 5.6 months) switchover, there were significant decreases in A1C (−0.35%; P = .0067) and weight (−1.6 kg; P = .0151). There were no significant changes in blood pressure or lipid levels. Two patients (2.5%) discontinued once weekly exenatide due to adverse reactions. Conclusion: Once weekly exenatide was generally well tolerated and significantly reduced A1C levels and body weight in patients with T2DM when switched from a shorter-acting GLP-1 analog.

Image analysis quantitation of immunoreactive retinoblastoma protein in human thyroid neoplasms with a streptavidin-biotin-peroxidase staining technique

Studies investigating the molecular pathogenesis of common thyroid neoplasms have shown altered expression and/or structure of proto-oncogenes, G-proteins, and growth factors. Growth suppressor genes, genomic DNA segments that code for proteins believed to function as growth suppressors, have not been evaluated for a potential role in the pathogenesis of thyroid neoplasms. The retinoblastoma gene (RB1) maps to chromosome 13q14 and encodes a 110 kilodalton variably phosphorylated nuclear protein (Rb) that functions as a growth suppressor in a wide variety of human tissues. The frequent association of Rb protein loss with multiple neoplasms has prompted the authors to apply a specific and rapid immunohistochemical technique using streptavidin-biotin-peroxidase technology evaluated by image analysis that can be used to quantitate the level of immunoreactive Rb protein (iRb) in thyroid neoplasms. In utilizing streptavidin-biotin technology for nuclear iRb detection, artifacts that can be associated with the use of avidin such as nonspecific binding at physiologic pH and nonspecific complex formation with cellular components including chromatin are avoided. By this method, positive nuclear staining for iRb in the follicular cells of three follicular adenomas and in CV-1 control cells known to express Rb was demonstrated. Two papillary carcinomas, two medullary carcinomas and a SAOS-2 cell line known to produce a defective form of Rb stained at significantly lower levels (P less than .001). The authors conclude that the streptavidin-biotin-peroxidase staining technique evaluated by image analysis is a sensitive and specific detection system for nuclear iRb studies; has significant advantages over previously used techniques; and that thyroid neoplasms may variably express iRb which may, in part, reflect their variable pathogenesis.