Successful use of problem-solving methodology to reduce pharmacy chemotherapy processing time.

OBJECTIVES: The primary objectives of this study were to (1) reduce pharmacy turnaround time (TAT) without compromising safety and quality and (2) reduce compounding order overload during peak hours (8:00 AM-5:00 PM). The secondary objective was to decrease patient wait time pertinent to pharmacy services. SETTING: The setting was a hospital-based pharmacy. PRACTICE DESCRIPTION: Pharmacy dispensing more than 1800 doses daily, 30% of which goes to outpatient cancer treatment. Patients usually receive multiple compounded medications; thus, compounding numbers are several folds higher than patient number. High compounded chemotherapy order volume overloaded pharmacy staff during peak hours and was a major contributor to patient wait time. PRACTICE INNOVATION: Using Define Measure Analyze Improve Control Six Sigma and intelligent risk-taking strategies, a dedicated team identified root causes of problems and designed long-lasting solutions that would not compromise quality. EVALUATION: The most effective initiative was the advanced preparation of chemotherapy for select patients (Concierge), which addressed pharmacy TAT, patient wait time, and chemotherapy order overload, all without affecting safety or quality of dispensed medications. RESULTS: Pharmacy TAT decreased by 77% for Concierge patients and 31% for standard patients. Comparable decreases were observed for patient wait time: 67% for Concierge and 27% for standard patients. Safety and quality were maintained for all dispensations during and after implementation of Concierge. A concurrent 8% increase in patient number was observed despite no changes in physical capacity. CONCLUSION: The implementation of Concierge initiatives: markedly reduced pharmacy TAT without compromising safety checks performed by pharmacists; decreased chemotherapy order overload during peak hours; improved distribution of assignments for pharmacy staffand statistically significant decreased wait time for all patients, especially those selected for Concierge. Effective selection of Concierge patients minimized additional costs associated with wasted premixed chemotherapy. Improving workflow for a subset of patients affected a greater patient population, allowing additional patients to be treated daily.

Cardiac expression of human type 2 iodothyronine deiodinase increases glucose metabolism and protects against doxorubicin-induced cardiac dysfunction in male mice.

Altered glucose metabolism in the heart is an important characteristic of cardiovascular and metabolic disease. Because thyroid hormones have major effects on peripheral metabolism, we examined the metabolic effects of heart-selective increase in T3 using transgenic mice expressing human type 2 iodothyronine deiodinase (D2) under the control of the α-myosin heavy chain promoter (MHC-D2). Hyperinsulinemic-euglycemic clamps showed normal whole-body glucose disposal but increased hepatic insulin action in MHC-D2 mice as compared to wild-type (WT) littermates. Insulin-stimulated glucose uptake in heart was not altered, but basal myocardial glucose metabolism was increased by more than two-fold in MHC-D2 mice. Myocardial lipid levels were also elevated in MHC-D2 mice, suggesting an overall up-regulation of cardiac metabolism in these mice. The effects of doxorubicin (DOX) treatment on cardiac function and structure were examined using M-mode echocardiography. DOX treatment caused a significant reduction in ventricular fractional shortening and resulted in more than 50% death in WT mice. In contrast, MHC-D2 mice showed increased survival rate after DOX treatment, and this was associated with a six-fold increase in myocardial glucose metabolism and improved cardiac function. Myocardial activity and expression of AMPK, GLUT1, and Akt were also elevated in MHC-D2 and WT mice following DOX treatment. Thus, our findings indicate an important role of thyroid hormone in cardiac metabolism and further suggest a protective role of glucose utilization in DOX-mediated cardiac dysfunction.

GnRH-deficient phenotypes in humans and mice with heterozygous variants in KISS1/Kiss1.

CONTEXT: KISS1 is a candidate gene for GnRH deficiency. OBJECTIVE: Our objective was to identify deleterious mutations in KISS1. PATIENTS AND METHODS: DNA sequencing and assessment of the effects of rare sequence variants (RSV) were conducted in 1025 probands with GnRH-deficient conditions. RESULTS: Fifteen probands harbored 10 heterozygous RSV in KISS1 seen in less than 1% of control subjects. Of the variants that reside within the mature kisspeptin peptide, p.F117L (but not p.S77I, p.Q82K, p.H90D, or p.P110T) reduces inositol phosphate generation. Of the variants that lie within the coding region but outside the mature peptide, p.G35S and p.C53R (but not p.A129V) are predicted in silico to be deleterious. Of the variants that lie outside the coding region, one (g.1-3659C→T) impairs transcription in vitro, and another (c.1-7C→T) lies within the consensus Kozak sequence. Of five probands tested, four had abnormal baseline LH pulse patterns. In mice, testosterone decreases with heterozygous loss of Kiss1 and Kiss1r alleles (wild-type, 274 ± 99, to double heterozygotes, 69 ± 16 ng/dl; r(2) = 0.13; P = 0.03). Kiss1/Kiss1r double-heterozygote males have shorter anogenital distances (13.0 ± 0.2 vs. 15.6 ± 0.2 mm at P34, P < 0.001), females have longer estrous cycles (7.4 ± 0.2 vs. 5.6 ± 0.2 d, P < 0.01), and mating pairs have decreased litter frequency (0.59 ± 0.09 vs. 0.71 ± 0.06 litters/month, P < 0.04) and size (3.5 ± 0.2 vs. 5.4 ± 0.3 pups/litter, P < 0.001) compared with wild-type mice. CONCLUSIONS: Deleterious, heterozygous RSV in KISS1 exist at a low frequency in GnRH-deficient patients as well as in the general population in presumably normal individuals. As in Kiss1(+/-)/Kiss1r(+/-) mice, heterozygous KISS1 variants in humans may work with other genetic and/or environmental factors to cause abnormal reproductive function.

Targeted deletion of one or two copies of the G protein ß subunit Gß5 gene has distinct effects on body weight and behavior in mice.

We investigated the physiological role of Gß5, a unique G protein ß subunit that dimerizes with regulators of G protein signaling (RGS) proteins of the R7 family instead of Gγ. Gß5 is essential for stability of these complexes, so that its knockout (KO)causes degradation of the entire Gß5-R7 family. We report that the Gß5-KO mice remain leaner than the wild type (WT) throughout their lifetime and are resistant to a high-fat diet. They have a 5-fold increase in locomotor activity, increased thermogenesis, and lower serum insulin, all of which correlate with a higher level of secreted epinephrine. Heterozygous (HET) mice are 2-fold more active than WT mice. Surprisingly, with respect to body weight, the HET mice display a phenotype opposite to that of the KO mice: by the age of 6 mo, they are ≥ 15% heavier than the WT and have increased adiposity, insulin resistance, and liver steatosis. These changes occur in HET mice fed a normal diet and without apparent hyperphagia, mimicking basic characteristics of human metabolic syndrome. We conclude that even a partial reduction in Gß5-R7 level can perturb normal animal metabolism and behavior. Our data on Gß5 haploinsufficient mice may explain earlier observations of genetic linkage between R7 family mutations and obesity in humans.

A GPR54-activating mutation in a patient with central precocious puberty.

Gonadotropin-dependent, or central, precocious puberty is caused by early maturation of the hypothalamic-pituitary-gonadal axis. In girls, this condition is most often idiopathic. Recently, a G protein-coupled receptor, GPR54, and its ligand, kisspeptin, were described as an excitatory neuroregulator system for the secretion of gonadotropin-releasing hormone (GnRH). In this study, we have identified an autosomal dominant GPR54 mutation--the substitution of proline for arginine at codon 386 (Arg386Pro)--in an adopted girl with idiopathic central precocious puberty (whose biologic family was not available for genetic studies). In vitro studies have shown that this mutation leads to prolonged activation of intracellular signaling pathways in response to kisspeptin. The Arg386Pro mutant appears to be associated with central precocious puberty.

The small polyphenolic molecule kaempferol increases cellular energy expenditure and thyroid hormone activation.

Disturbances in energy homeostasis can result in obesity and other metabolic diseases. Here we report a metabolic pathway present in normal human skeletal muscle myoblasts that is activated by the small polyphenolic molecule kaempferol (KPF). Treatment with KPF leads to an approximately 30% increase in skeletal myocyte oxygen consumption. The mechanism involves a several-fold increase in cyclic AMP (cAMP) generation and protein kinase A activation, and the effect of KPF can be mimicked via treatment with dibutyryl cAMP. Microarray and real-time PCR studies identified a set of metabolically relevant genes influenced by KPF including peroxisome proliferator-activated receptor gamma coactivator-1alpha, carnitine palmitoyl transferase-1, mitochondrial transcription factor 1, citrate synthase, and uncoupling protein-3, although KPF itself is not a direct mitochondrial uncoupler. The cAMP-responsive gene for type 2 iodothyronine deiodinase (D2), an intracellular enzyme that activates thyroid hormone (T3) for the nucleus, is approximately threefold upregulated by KPF; furthermore, the activity half-life for D2 is dramatically and selectively increased as well. The net effect is an approximately 10-fold stimulation of D2 activity as measured in cell sonicates, with a concurrent increase of approximately 2.6-fold in the rate of T3 production, which persists even 24 h after KPF has been removed from the system. The effects of KPF on D2 are independent of sirtuin activation and only weakly reproduced by other small polyphenolic molecules such as quercetin and fisetin. These data document a novel mechanism by which a xenobiotic-activated pathway can regulate metabolically important genes as well as thyroid hormone activation and thus may influence metabolic control in humans.

Chronic cardiac-specific thyrotoxicosis increases myocardial beta-adrenergic responsiveness.

Whereas many cardiac symptoms of thyrotoxicosis resemble those of the hyperadrenergic state, circulating catecholamines are reduced or normal in this condition. To test the hypothesis that the thyrotoxic heart is hypersensitive to catechol-amines, we studied beta-adrenergic signaling in a transgenic (TG) mouse in which the human type 2 iodothyronine deiodinase (D2) gene is expressed in myocardium. Because D2 converts T4 to T3, the active form of thyroid hormone, the D2 TG mouse exhibits mild, chronic thyrotoxicosis that is limited to the myocardium. In the current study, we determined that cAMP accumulation in response to either norepinephrine or forskolin treatment was increased in isolated ventricular myocardiocytes and membrane-enriched fractions prepared from these D2 TG hearts as compared with wild type. This increase in adenylyl cyclase (AC) Vmax could not be explained by changes in AC isoform expression or changes in the long or short forms of stimulatory G-protein Gsalpha, which were approximately 10% decreased in D2 TG membranes. However, Western analysis and ADP-ribosylation studies suggest that the increase in AC Vmax is mediated by a decrease in the expression of inhibitory G proteins (Gialpha-3 and/or Goalpha). These data suggest that cardiac thyrotoxicosis leads to increased beta-adrenergic responsiveness of cardiomyocytes via alterations in the regulatory G-protein elements of the AC membrane complex.

Thyroid hormone and adrenergic signaling in the heart

A ação do hormônio tireoideano tem consequências profundas no sistema cardiovascular, as quais variam desde fibrilação atrial ao colapso hemodinâmico. Há muito sabe-se que os sinais e sintomas cardiovasculares detectados na tireotoxicose assemelham-se aos observados em estados hiper-adrenérgicos. Entretanto, as concentrações séricas de catecolaminas em pacientes com tireotoxicose são tipicamente normais ou mesmo baixas, sugerindo um aumento na responsividade adrenérgica no coração tireotóxico. A despeito de várias décadas de trabalho, a questão sobre se o hormônio tireoideano aumenta a responsividade adrenérgica é ainda controversa. Nesta revisão, nós consideramos os motivos que alimentam esta controvérsia, focalizando na complexidade da cascata de sinalização adrenérgica.