Suppression of rat and human growth hormone and prolactin secretion by a novel somatostatin/dopaminergic chimeric ligand

As cotreatment of somatostatin (SRIF) and dopamine (DA) agonists reduces GH in acromegaly more effectively than either agonist alone, SRIF and DA receptors (SSTR and DAR) may interact with enhanced functional activity. The selective SSTR2 agonist, BIM-23023 (50% effective dose, 0.42), and the DAR2 agonist, BIM-53097 (50% effective dose, 22.1), dose- dependently inhibited GH secretion in cultured primary rat and human fetal as well as in human pituitary tumor cells derived from GH-secreting adenomas. The combination of individual SSTR2 and DAR2 agonists was additive for suppressing GH secretion in both rat and human pituitary cells. BIM-23A387 is a chimeric compound that contains structural elements of both SRIF and DA in a single molecule and retains potent, selective binding to DAR2 and SSTR2. BIM-23A387 (50% effective dose, 0.16 for SSTR2 and 24.5 for DAR2), displayed similar efficacy in suppressing GH secretion from rat pituitary cells as the combination of the two individual agonists. In contrast, the chimeric molecule was more potent than individual selective analogs in suppressing GH secretion by human fetal pituitary and GH-secreting adenoma cells (P < 0.05). Although the DAR2 antagonist, sulpiride, reversed BIM-23A387-induced GH suppression, blockade of SSTR2 by the selective SSTR antagonist, BIM-23454, did not block BIM-23A387-suppressed GH secretion. These results indicate that mechanisms by which the chimeric molecule suppresses pituitary GH secretion may not be mediated by individual SSTR2 or DAR2 signaling, respectively. Functional interaction of the two receptors may explain the clinical observation that more effective GH suppression is achieved when DAR2 and SSTR2 agonists are administered in combination. The SRIF/DA chimeric molecule, BIM-23A387, represents a novel tool for effective drug treatment of acromegaly and for prolactinomas otherwise resistant to dopaminergic therapy.     

Methods for the economic and quality of life supplement to the cilostazol for RESTenosis (CREST) trial

OBJECTIVE: To determine economic and quality of life outcomes for the Cilostazol for RESTenosis (CREST) trial, which is investigating the efficacy of cilostazol vs. placebo in preventing post-stent restenosis. DESIGN: CREST is a prospective, multicenter, randomized, placebo-controlled, double-blind trial. SETTING: 20 clinical sites; the Emory Center for Outcomes Research (ECOR) will serve as the economic and data coordinating center. PATIENTS: 705 patients (>18 years) who have undergone successful, uncomplicated placement of an intracoronary stent in a native coronary artery. INTERVENTION: Cilostazol (100 mg twice daily) or placebo for 6 months. OUTCOME MEASURES: Costs: Primary endpoint, total direct medical costs at 6 months; secondary endpoints, initial hospital costs and follow-up costs. QOL: Health-related quality of life (QOL) will be assessed using the EQ-5D and the Seattle Angina Questionnaire at baseline and at 1, 3, and 6 months. Cost-effectiveness analysis: Preliminary data show that cilostazol is clinically superior to placebo and if the mean cost for the cilostazol arm is higher than that for placebo, cost-effectiveness analysis will be determined for the cost per episode of restenosis prevented, the cost per episode of major clinical and angiographic endpoints averted, and the cost per quality-adjusted life-years gained.     

Somatostatin and dopamine-somatostatin multiple ligands directed towards somatostatin and dopamine receptors in pituitary adenomas

AIM: We report the comparative efficacy of octreotide, cabergoline and multiple ligands directed towards the different somatostatin subtypes (ssts), such as BIM-23A779 and SOM-230, and of chimeric analogs which bind both somatostatin and the dopamine D2 receptors (D2R), such as BIM-23A760 and BIM-23A781, in cell cultures from human growth hormone (GH)-secreting pituitary adenomas. PROCEDURES: RT-PCR analysis of the quantitative expression of the different ssts and D2R mRNAs was performed on tumor fragments of 22 GH-secreting adenomas collected after surgery. Pharmacological studies, using the different ligands, were performed on cell cultures of such tumors. RESULTS: sst2, sst5 and D2R were constantly coexpressed in all tumors, in variable amounts. The levels of expression of sst2 and D2R mRNAs were significantly correlated with the maximal GH suppression by either octreotide or cabergoline (p < 0.001). In each tumor tested, 3 patterns of response, in terms of GH suppression, were observed. GH secretion was preferentially inhibited by the sst2 preferential compound octreotide in 61% of the tumors. In 19% of the tumors, the maximal inhibition of GH release was achieved with the sst5 preferential compound BIM-23268. The dopamine analog cabergoline was the most effective inhibitor of GH secretion in 21% of cases. Among the compounds tested, the most potent inhibitors of GH secretion were the sst2, sst5, D2R chimeric compound BIM-23A760, followed by the sst universal ligand SOM-230. CONCLUSIONS: The variable patterns of response to sst2, sst5 and dopamine D2 analogs may explain the greater efficacy of drugs which bind to the 3 receptors in suppressing GH secretion. The biological potency (EC50) and efficacy of the chimeric compound BIM-23A760 on GH secretion can be partly explained by its high affinity for sst2. The effect of multiple receptor activation on the functions of other pituitary tumor types, such as prolactinomas and corticotropinomas, is not presently analyzed, and the efficacy of multireceptor ligands remains to be elucidated.     

Dopamine receptor subtype 2 and somatostatin receptor subtype 5 expression influences somatostatin analogs effects on human somatotroph pituitary adenomas in vitro

Dopamine (DA) and somatostatin (SRIF) receptor agonists inhibit growth hormone (GH) secretion by pituitary adenomas. We investigated DA subtype 2 receptor (DR2) and SRIF receptor (sst) subtypes 2 and 5 expression in 25 GH-secreting pituitary adenomas and tested in primary culture the effects on GH and prolactin (PRL) secretion of sst agonists selectively interacting with sst2 (BIM-23120), sst5 (BIM-23206), and sst2 and sst5 (BIM-23244). All adenomas expressed sst2; eight adenomas expressed both sst5 and DR2, eight sst5 but not DR2, and eight DR2 but not sst5. One tissue lacked expression of DR2 and sst5. GH secretion was inhibited by BIM-23120 in all samples, while it was reduced by BIM-23206 only in adenomas not expressing DR2. BIM-23120's inhibitory effects correlated with sst2 and DR2 expression, whereas DR2 expression correlated inversely with BIM-23206 inhibitory effects on GH secretion. In seven mixed GH-/PRL-secreting pituitary adenomas, PRL secretion was inhibited in sst5-expressing tumors by BIM-23206, but not by BIM-23120. BIM-23244 reduced PRL secretion only in adenomas expressing sst2, sst5 and DR2. sst5 and DR2 expression correlated directly with BIM23206 inhibitory effects on PRL secretion. Our results suggest that adenomas expressing DR2 are less likely to respond to clinically available SRIF analogs in terms of GH secretion inhibition. Therefore, drugs interacting also with DR2 might better control secretion of pituitary adenomas.     

Is the Availability of Hospital IT Applications Associated with a Hospital’s Risk Adjusted Incidence Rate for Patient Safety Indicators: Results from 66 Georgia Hospitals

This study examines the associations between the availability of IT applications in a hospital and that hospital’s risk adjusted incidence rate per 1,000 hospitalizations for Agency for Healthcare Research and Quality’s (AHRQ) 15 Patient Safety Indicators (PSIs). The study population consists of a convenience sample of 66 community hospitals in Georgia that completed a Hospital IT survey by December 2003 and provided data to Georgia Hospital Discharge Data Set during 2004. AHRQ’s PSI software was used to estimate risk adjusted incidence rates. Differences in means, Pearson correlation coefficients, and multivariate regression analysis were used to determine if the availability of IT applications were associated with better PSI outcomes. This study finds very little statistically significant correlation between the availability of IT applications and risk adjusted PSI incident rate per 1,000 hospitalizations. In the multivariate regression models, the overall availability of IT applications in a hospital was significantly and negatively associated with the risk adjusted incident rate for only postoperative hemorrhage or hematoma. The count of functional applications available was negatively associated with postoperative hemorrhage or hematoma and foreign body left during procedure, while the count of technological devices was only associated with postoperative hemorrhage or hematoma. This study finds that the overall number of functional applications and technological devices available in a hospital is not associated with improved risk adjusted PSI outcomes. Future research is needed to examine if specific IT applications in specific clinical areas of the hospital are associated with improved PSI outcomes.     

A phase I study of the biomodulation of capecitabine by docetaxel and gemcitabine (mGTX) in previously untreated patients with metastatic adenocarcinoma of the pancreas

Background

Pancreas cancer remains a formidable challenge. We report the first prospective analysis of the 3-drug combination of gemcitabine (G), docetaxel (T) and capecitabine (X) (mGTX) with schedule modification to maximize biomodulation of X.

Methods

We conducted a dose escalation study of mGTX in first-line treatment of metastatic pancreas cancer using three dose levels (DL 1-3). Patients received docetaxel on days 1 and 8, gemcitabine on days 8 and 15, and capecitabine on days 8 through 21. Gemcitabine dose was fixed at 750?mg/m² over 75?min, capecitabine was given twice daily and escalated from 500 to 650?mg/m² at DL2 and docetaxel increased from 30 to 36?mg/m² at DL3.

Results

Twenty-one patients (18 evaluable) were enrolled in the study. MTD was reached at DL3 and one DLT was observed at DL2 (prolonged neutropenia). The most common grade 3/4 toxicities were leukopenia (29%) and neutropenia (29%) and fatigue (25%). Tumor growth control rate was 80% (11% PR; 69% SD lasting at least 3?months). Median progression-free-survival was 5.8?months (95% CI 2.7, 10.6) and median overall survival was 7.4?months (95% CI 3.8 16.8). CA 19-9 decreased by at least 50% from baseline in half the patients.

Conclusion

mGTX demonstrates acceptable tolerability with interesting activity in patients with pancreatic cancer. The recommended doses for phase II studies are docetaxel 36?mg/m² days 1 and 8, gemcitabine 750?mg/m² over 75?min days 8 and 15, and capecitabine 625?mg/m² twice daily days 8 through 21.     

The financial and nonfinancial costs of implementing electronic health records in primary care practices

The incentives in the American Recovery and Reinvestment Act to expand the "meaningful use" of electronic health record systems have many health care professionals searching for information about the cost and staff resources that such systems require. We report the cost of implementing an electronic health record system in twenty-six primary care practices in a physician network in north Texas, taking into account hardware and software costs, as well as the time and effort invested in implementation. For an average five-physician practice, implementation cost an estimated $162,000, with $85,500 in maintenance expenses during the first year. We also estimate that the HealthTexas network implementation team and the practice implementation team needed 611 hours, on average, to prepare for and implement the electronic health record system, and that "end users"-physicians, other clinical staff, and nonclinical staff-needed 134 hours per physician, on average, to prepare for use of the record system in clinical encounters.     

Cohort differences in self-rated health: evidence from a three-decade, community-based, longitudinal study of women

Despite the fact that life expectancy has nearly doubled over the past century, the US public has become increasingly preoccupied with issues of health and illness. In this study, the authors investigated cohort differences in self-rated health between women born in 1935-1944 (preboomers) and women born in 1945-1954 (baby boomers). A randomly selected, community-based sample of 618 mothers, 314 preboomers, and 304 baby boomers was interviewed. Over three decades, self-rated health was assessed in 1975, 1983, 1985-1986, 1991-1994, and 2001-2004. An individual growth model showed a linear decline (-0.61 per year, p<0.001) in self-rated health from mean ages 31-59 years combined, with a quadratic age effect (-0.03, p<0.001). Baby boomers reported lower self-rated health (mean difference, -5.30; p<0.001) and more rapid decline per year (slope difference, -0.52; p<0.001) than did preboomers of overlapping ages; those differences remained after adjusting for demographics, socioeconomic variables, personality factors, health behaviors, chronic illness, and depression symptoms. Study findings have important implications with regard to the potential growing burden on the nation's health care system, suggesting that generational changes in health evaluations and expectations may continue to increase demand for medical care.     

Destruction of testicular Leydig cells reveals a role of endogenous inhibin in regulating follicle-stimulating hormone secretion in the adult male rat

It has previously been demonstrated that passive immunoneutralization of endogenous inhibin results in a dramatic elevation in follicle-stimulating hormone (FSH) secretion in the adult female rat but not in the adult male. The purpose of the present study was to investigate whether the effects of immunoneutralizing endogenous inhibin on FSH secretion in the adult male rat might be masked by the presence of additional, compensating, FSH-suppressing factors. This was determined by examining the individual and combined effects of removing the testicular influences provided by the Leydig cells using the selective toxicant, ethane dimethane sulfonate (EDS), and passive immunoneutralization of endogenous inhibin. Within 24 h of a single i.p. injection of EDS, plasma testosterone levels were lowered to near assay limits and by 3 days were undetectable. Plasma FSH levels were significantly elevated 3 and 7 days after EDS treatment, but not to the levels observed in rats castrated for similar periods of time. Castration of rats, treated 3 days earlier with EDS, resulted in a further significant increase in FSH secretion as compared with EDS-treated, sham-operated controls, indicating that the testes were providing an additional FSH-suppressing factor(s) other than those originating in the Leydig cells. Injection of anti-inhibin serum, into rats treated 3 or 7 days earlier with EDS, induced a further significant increase in FSH secretion that raised plasma FSH to a level comparable to that observed in male rats castrated for similar periods of time. Plasma LH secretion was also dramatically elevated by EDS treatment to levels that equaled or exceeded those observed in similarly timed castrates. Pituitary sensitivity, as tested by the injection of an exogenous challenge of luteinizing hormone-releasing hormone (LHRH), was significantly increased 3 or 7 days after either EDS treatment or castration in terms of LHRH-stimulated LH release, but not in terms of LHRH-stimulated FSH release. Immunoneutralization of endogenous inhibin induced no further observable changes in pituitary sensitivity to LHRH. These results demonstrate that in the absence of the Leydig cells a secondary role is revealed for endogenous inhibin in suppressing FSH secretion that, in combination with the Leydig cell influence(s), accounts for the postcastration increase in FSH. The need to remove the Leydig cell influence(s) to reveal an effect of endogenous inhibin on FSH secretion in the adult male rat may suggest that the inhibin effect is normally masked by the presence of the comparatively larger suppressive influence(s) derived from the Leydig cells.(ABSTRACT TRUNCATED AT 400 WORDS)     

The Interplay Between Policy and COVID-19 Outbreaks in South Asia: Longitudinal Trend Analysis of Surveillance Data

BackgroundCOVID-19 transmission rates in South Asia initially were under control when governments implemented health policies aimed at controlling the pandemic such as quarantines, travel bans, and border, business, and school closures. Governments have since relaxed public health restrictions, which resulted in significant outbreaks, shifting the global epicenter of COVID-19 to India. Ongoing systematic public health surveillance of the COVID-19 pandemic is needed to inform disease prevention policy to re-establish control over the pandemic within South Asia.ObjectiveThis study aimed to inform public health leaders about the state of the COVID-19 pandemic, how South Asia displays differences within and among countries and other global regions, and where immediate action is needed to control the outbreaks.MethodsWe extracted COVID-19 data spanning 62 days from public health registries and calculated traditional and enhanced surveillance metrics. We use an empirical difference equation to measure the daily number of cases in South Asia as a function of the prior number of cases, the level of testing, and weekly shifts in variables with a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano–Bond estimator in R.ResultsTraditional surveillance metrics indicate that South Asian countries have an alarming outbreak, with India leading the region with 310,310 new daily cases in accordance with the 7-day moving average. Enhanced surveillance indicates that while Pakistan and Bangladesh still have a high daily number of new COVID-19 cases (n=4819 and n=3878, respectively), their speed of new infections declined from April 12-25, 2021, from 2.28 to 2.18 and 3.15 to 2.35 daily new infections per 100,000 population, respectively, which suggests that their outbreaks are decreasing and that these countries are headed in the right direction. In contrast, India’s speed of new infections per 100,000 population increased by 52% during the same period from 14.79 to 22.49 new cases per day per 100,000 population, which constitutes an increased outbreak.ConclusionsRelaxation of public health restrictions and the spread of novel variants fueled the second wave of the COVID-19 pandemic in South Asia. Public health surveillance indicates that shifts in policy and the spread of new variants correlate with a drastic expansion in the pandemic, requiring immediate action to mitigate the spread of COVID-19. Surveillance is needed to inform leaders whether policies help control the pandemic.