scispace - formally typeset
Search or ask a question

Showing papers by "Eli Lilly and Company published in 1994"


Journal ArticleDOI
07 Oct 1994-Science
TL;DR: A strong candidate for the 17q-linked BRCA1 gene, which influences susceptibility to breast and ovarian cancer, has been identified by positional cloning methods.
Abstract: A strong candidate for the 17q-linked BRCA1 gene, which influences susceptibility to breast and ovarian cancer, has been identified by positional cloning methods. Probable predisposing mutations have been detected in five of eight kindreds presumed to segregate BRCA1 susceptibility alleles. The mutations include an 11-base pair deletion, a 1-base pair insertion, a stop codon, a missense substitution, and an inferred regulatory mutation. The BRCA1 gene is expressed in numerous tissues, including breast and ovary, and encodes a predicted protein of 1863 amino acids. This protein contains a zinc finger domain in its amino-terminal region, but is otherwise unrelated to previously described proteins. Identification of BRCA1 should facilitate early diagnosis of breast and ovarian cancer susceptibility in some individuals as well as a better understanding of breast cancer biology.

6,118 citations


Journal Article
TL;DR: Kinetic analysis demonstrates that wortmannin is a noncompetitive, irreversible inhibitor of phosphatidylinositol-3-kinase, with inactivation being both time- and concentration-dependent.
Abstract: Phosphatidylinositol-3-kinase is an important enzyme for intracellular signaling. The microbial product wortmannin and some of its analogues have been shown to be potent inhibitors of phosphatidylinositol-3-kinase. The 50% inhibitory concentration for inhibition by wortmannin is 2 to 4 nM. Kinetic analysis demonstrates that wortmannin is a noncompetitive, irreversible inhibitor of phosphatidylinositol-3-kinase, with inactivation being both time- and concentration-dependent. Wortmannin has previously been reported to be an inhibitor of myosin light chain kinase but with an inhibitory concentration of 0.2 microM. Wortmannin was found not to be an inhibitor of phosphatidylinositol-4-kinase, protein kinase C, or protein tyrosine kinase. Wortmannin inhibited the formation of phosphatidylinositol-3-phosphates in intact cells. The results of the study suggest that wortmannin and its analogues may have utility as pharmacological probes for studying the actions of phosphatidylinositol-3-kinase.

721 citations


Journal ArticleDOI
TL;DR: Raloxifene has promise as an agent with beneficial bone and cardiovascular effects in the absence of significant uterine effects, and ethynyl estradiol diverged dramatically from estrogen in its lack of significant estrogenic effects on uterine tissue.
Abstract: There is a medical need for an agent with the positive effects of estrogen on bone and the cardiovascular system, but without the negative effects on reproductive tissue. Raloxifene (LY139481 HCI) is a benzothiophene derivative that binds to the estrogen receptor and inhibits the effects of estrogen on the uterus. In an ovariectomized (OVX) rat model we investigated the effects of raloxifene on bone loss (induced by estrogen deficiency), serum lipids, and uterine tissue. After oral administration of raloxifene for 5 wk (0.1-10 mg/kg per d) to OVX rats, bone mineral density in the distal femur and proximal tibia was significantly greater than that observed in OVX controls (ED50 of 0.03-0.3 mg/kg). Serum cholesterol was lower in the raloxifene-treated animals, which had a minimal effective dose of 0.1 mg/kg and an approximate oral ED50 of 0.2 mg/kg. The effects of raloxifene on bone and serum cholesterol were comparable to those of a 0.1-mg/kg per d oral dose of ethynyl estradiol. Raloxifene diverged dramatically from estrogen in its lack of significant estrogenic effects on uterine tissue. Ethynyl estradiol produced a marked elevation in a number of uterine histologic parameters (e.g., epithelial cell height, stromal eosinophilia). These data suggest that raloxifene has promise as an agent with beneficial bone and cardiovascular effects in the absence of significant uterine effects.

676 citations


Journal ArticleDOI
01 Mar 1994-Diabetes
TL;DR: Although the addition of zinc retarded the absorption of LYSPRO slightly, it displays faster pharmacodynamic action than human Regular insulin when injected subcutaneously and retains its distinct profile.
Abstract: [Lys(B28, Pro(B29)]-human insulin (LYSPRO) is an insulin analogue in which the natural amino acid sequence of the B-chain at positions 28 and 29 is inverted. These changes result in an insulin molecule with a greatly reduced capacity for self-association in solution. These clinical studies were designed to compare LYSPRO with human Regular insulin after subcutaneous injection in humans. We wanted to evaluate the effect of adding zinc to LYSPRO on its pharmacokinetics and pharmacodynamics. In addition, we compared the pharmacokinetics and pharmacodynamics of LYSPRO and human Regular insulin after subcutaneous injection to those of human Regular insulin given intravenously. Thus, we compared four treatments: solutions of zinc-free LYSPRO given subcutaneously (A), zinc-containing LYSPRO given subcutaneously (B), human Regular insulin given subcutaneously (C), and human Regular insulin given intravenously (D). We gave a 10-U dose of each treatment to 10 healthy (nondiabetic) men during glucose clamps. Serum insulin concentrations peaked more than two times higher (maximum serum insulin level [Cmax], 698 vs. 308 pM, A vs. C) and in less than half the time (time to Cmax [Tmax], 42 vs. 101 min, A vs. C) after subcutaneous injection of zinc-free LYSPRO. At the same time, the glucose infusion rate peaked in about half the time (time to maximum glucose infusion rate [TRmax], 99 vs. 179 min, A vs. C) and was slightly but not significantly higher (maximum glucose infusion rate [Rmax], 3.1 vs. 2.2 mmol/min, A vs. C) than that of human Regular insulin.(ABSTRACT TRUNCATED AT 250 WORDS)

494 citations


Journal ArticleDOI
TL;DR: Evaluation of anti-HIV activity with eight derivatives of 1 revealed that dihydrobetulinic acid was also a potent inhibitor of HIV replication, and there was no apparent correlation between anti-hIV activity and the inhibition of PKC among these compounds.
Abstract: Betulinic acid [1] and platanic acid [2], isolated from the leaves of Syzigium claviflorum, were found to be inhibitors of HIV replication in H9 lymphocyte cells. Evaluation of anti-HIV activity wich eight derivatives of 1 revealed that dihydrobetulinic acid [3] was also a potent inhibitor of HIV replication. The C-3 hydroxy group and C-17 carboxylic acid group, as well as the C-19 substituents, contribute to enhanced anti-HIV activity. The inhibitory activity of these compounds against protein kinase C (PKC) was also examined, since a correlation between anti-HIV and anti-PKC activities has been suggested. However, there was no apparent correlation between anti-HIV activity and the inhibition of PKC among these compounds

467 citations


Journal ArticleDOI
TL;DR: Gemcitabine demonstrated marginal activity in this resistant neoplasm, without excessive toxicity, and further evaluation, including the use of more intense dosing and/or combination therapy, is warranted.
Abstract: Gemcitabine is a novel nucleoside analog which demonstrated a broad spectrum of preclinical acitivity in solid tumor models, and responses in patients with pancreas cancer during phase I evaluation. Patients with measurable adenocarcinoma of the pancreas who had received no previous chemotherapy were eligible for this multicenter phase II clinical trial. Gemcitabine 800 mg/m2 was administered intravenously weekly for 3 consecutive weeks, followed by one week rest, every 4 weeks. Forty-four patients entered the trial; 35 had at least 2 cycles of therapy. Partial response was observed in 5 patients (11%, estimated 95% confidence interval 2–20%), with a median duration of 13 months. All responding patients had stabilization or improvement in performance status. Fourteen patients had stable disease of 4 or more months. The median WBC nadir was 3.8 × 103/μl (range 1.6–9.3) and the median absolute neutrophil (ANC) nadir was 2.0 × 103/μl (range 0.4–7.2). Thrombocytopenia - 100.0 × 103/μl was observed in 15 patients; the median platelet nadir was 123.0 (range 30.0–245.0). All patients experienced a mild to moderate flu-like syndrome. In addition, one patient had a mild hemolytic-uremic syndrome which appeared related to gemcitabine therapy. Gemcitabine demonstrated marginal activity in this resistant neoplasm, without excessive toxicity. Further evaluation, including the use of more intense dosing and/or combination therapy, is warranted.

448 citations


Journal ArticleDOI
TL;DR: In this article, a conceptual framework for the relationship between job rotation and selected career-related variables is proposed, based on related literature and an inductive pilot study, and a test on 255 employee...
Abstract: Drawing on related literature and an inductive pilot study, we propose a conceptual framework for the relationship between job rotation and selected career-related variables. A test on 255 employee...

441 citations


Journal Article
TL;DR: CD spectroscopy is used to demonstrate that A beta secondary structure is an important determinant of A beta toxicity and provide additional support for the hypothesis that Abeta can have a causal role in the molecular neuropathology of Alzheimer's disease.
Abstract: Amyloid beta peptide (A beta), the major protein constituent of senile plaques in patients with Alzheimer's disease, is believed to facilitate the progressive neurodegeneration that occurs in the latter stages of this disease. Early attempts to characterize the structure-activity relationship of A beta toxicity in vitro were compromised by the inability to reproducibly elicit A beta-dependent toxicity across different lots of chemically equivalent peptides. In this study we used CD spectroscopy to demonstrate that A beta secondary structure is an important determinant of A beta toxicity. Solubilized A beta was maximally toxic when the peptide adopted a beta-sheet conformation. Three of the four A beta lots tested had a random coil conformation and were weakly toxic or inactive, whereas the single A beta lot exhibiting toxic activity at low peptide concentrations had significant beta-sheet structure. Incubation of the weakly toxic A beta lots in aqueous stock solutions for several days before use induced a time-dependent conformational transition from random coil to beta-sheet and increased A beta toxicity in three different toxicity assays. Furthermore, the secondary structure of preincubated A beta was dependent upon peptide concentration and pH, so that beta-sheet structures were attenuated when peptide solutions were diluted or buffered at neutral and basic pH. Our data could explain some of the variable toxic activity that has been associated with A beta in the past and provide additional support for the hypothesis that A beta can have a causal role in the molecular neuropathology of Alzheimer's disease.

407 citations


Journal ArticleDOI
TL;DR: CYP3A4, CYP3A5, and fetal microsomes containing CYP 3A7 catalyze 1'- and 4-hydroxymidazolam with the ratio of these metabolites indicative of the CYP1A form with a 2-fold greater rate than a reconstituted system with CYP2A4.

396 citations


Journal ArticleDOI
TL;DR: CYP3A4 and CYP3A5 are present throughout the human digestive tract and that differences in the expression of these enzymes may account for inter-organ Differences in the metabolism of CYP 3A substrates.
Abstract: CYP3A4, a major Phase I xenobiotic metabolizing enzyme present in liver, is also present in human small bowel epithelium where it appears to catalyse significant 'first pass' metabolism of some drugs. To determine whether CYP3A4 or the related enzymes CYP3A3, CYP3A5, and CYP3A7 are present in other regions of the digestive tract, we used CYP3A-specific antibodies to examine histological sections and epithelial microsomes obtained from a human organ donor. CYP3A-related proteins were detected in epithelia throughout the digestive tract and in gastric parietal cells, in pericentral hepatocytes, and in ductular cells of the pancreas. Immunoblot analysis suggested that the major CYP3A protein present in liver, jejunum, colon, and pancreas was CYP3A4 or CYP3A3, whereas CYP3A5 was the major protein present in stomach. Both CYP3A4 and CYP3A5 mRNA were detectable in all regions of the digestive tract using the polymerase chain reaction (PCR); however, only CYP3A4 could be detected by Northern blot analysis. CYP3A7 mRNA was consistently detected only in the liver by PCR and CYP3A3 mRNA was not detected in any of the tissues. We conclude that CYP3A4 and CYP3A5 are present throughout the human digestive tract and that differences in the expression of these enzymes may account for inter-organ differences in the metabolism of CYP3A substrates.

387 citations


Journal ArticleDOI
TL;DR: The pradimicins show the ability to bind mannan and thus exert an antifungal effect, and their unique action may provide a better understanding of mannan as a target.
Abstract: The discovery of antifungal agents that possess selective toxicity against the eukaryotic fungal cell remains an important scientific challenge. The growing medical need for safe and effective antifungal agents stems from the rapidly increasing population of immunocompromise d patients. Although the treat­ ment of fungal infections is progressing steadily, currently available agents act on targets that are also found in mammalian cells. Ideally, a selectively toxic

Journal ArticleDOI
TL;DR: This review seeks to summarize the current state of knowledge regarding the obesity, stimulation of somatic growth, and enhancement of tumor formation caused by the Avy mutation, and to interpret these pleiotropic effects in terms of the normal function of the agouti protein.
Abstract: The viable yellow A(vy) mutation results in a mottled yellow mouse that is obese, slightly larger than its nonyellow sibs, and more susceptible to tumor formation in those tissues sensitized by the strain genome. The mutation exhibits variable expressivity resulting in a continuum of coat color phenotypes, from clear yellow to pseudoagouti. The mouse agouti protein is a paracrine signaling molecule that induces hair follicle melanocytes to switch from the synthesis of black pigment to yellow pigment. Molecular cloning studies indicate that the obesity and growth effects of the A(vy) mutation result from ectopic expression of the normal agouti gene product. This review seeks to summarize the current state of knowledge regarding the obesity, stimulation of somatic growth, and enhancement of tumor formation caused by the A(vy) mutation, and to interpret these pleiotropic effects in terms of the normal function of the agouti protein.

Journal ArticleDOI
TL;DR: Using polymerase chain reaction amplification of reverse‐transcribed RNA isolated from adult rat satellite cells, a temporal sequence of gene activation is demonstrated, distinct from that previously observed in embryonic somitic cells.
Abstract: The satellite cell is responsible for growth and repair of postnatal skeletal muscle. We investigated the expression of the myogenic regulatory gene (MRG) family in these cells in the stages from quiescence to fusion. Using polymerase chain reaction amplification of reverse-transcribed RNA (RT-PCR) isolated from adult rat satellite cells, we demonstrated a temporal sequence of gene activation, which is distinct from that previously observed in embryonic somitic cells. No MRG expression was detected in predominantly quiescent cells. MyoD is activated by 12 h in cell culture, prior to the first evidence of proliferation. MRF4 and myf-5 appear by 48 h and may be associated with the first division cycle. Myogenin is not detectable until 72 h after satellite cell recovery from the muscle fiber, coincidental with the first evidence of differentiation. © 1994 wiley-Liss, Inc.


Journal ArticleDOI
TL;DR: The physiological role of the serotonin transporter on serotonin neuronal membranes apparently is to inactivate serotonin that has been released into the synaptic cleft, and serotonin neurons decrease their firing and release of serotonin to limit the magnitude of the increase in extracellular serotonin concentration.

Journal ArticleDOI
TL;DR: Fluoxetine was associated with a statistically significant reduction in OCD severity, including time engaged in obsessional and/or compulsive behaviors, and greater efficacy at 60 mg/d was observed.
Abstract: Objectives: To determine the effectiveness of fluoxetine hydrochloride at fixed doses of 20 mg/d, 40 mg/d, and 60 mg/d in patients with obsessive-compulsive disorder (OCD) and to evaluate its safety. Methods: Fixed-dose fluoxetine hydrochloride (20 mg/d, 40 mg/d, 60 mg/d) was compared with placebo in two randomized, double-blind, parallel, 13-week trials of identical design in 355 outpatients with OCD aged 15 to 70 years ( DSM-III-R criteria; 1 year's duration or longer; depression secondary if present). Results: Fluoxetine (all doses) was significantly ( P ±001) superior to placebo on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) total score (mean baseline-to-end—point decrease, 4.6,5.5, and 6.5 vs 0.9, respectively, studies pooled) and other efficacy measures ( P ±01). A trend suggesting greater efficacy at 60 mg/d was observed. Most patients (79.2%) completed the study. Eight adverse events were statistically significantly more frequent with fluoxetine and one, with placebo. For some events, incidence tended to increase with increasing dosage; however, few patients discontinued treatment for any single event. Conclusion: Fluoxetine was associated with a statistically significant reduction in OCD severity, including time engaged in obsessional and/or compulsive behaviors. Adverse events infrequently led to study discontinuation.

Patent
01 Apr 1994
TL;DR: A hand-held dual liquid medication injector (100, 400) having dual, bi-directional dosage metering mechanisms (252, 253, 410) for permitting a variable dosage amount for each cartridge (104, 106) of liquid medication as mentioned in this paper.
Abstract: A hand-held dual liquid medication injector (100, 400) having dual, bi-directional dosage metering mechanisms (252, 253, 410) for permitting a variable dosage amount for each cartridge (104, 106) of liquid medication. The medications are mixed within a manifold (122) having a valved mixing chamber (14) and are injected via a single cannula (121). The mixing chamber is valved (136) such that backflow of mixed or unmixed medications into the cartridges is prevented. An injection mechanism (116, 254, 412), independent of the metering mechanism, loads and injects the liquid medication. In one embodiment, transverse movement of the injection mechanism (116) during injection is translated into horizontal movement by the plunger mechanism. In another embodiment, a power-assisted plunger mechanism (412) accomplishes injection.

Journal ArticleDOI
03 Jun 1994-Science
TL;DR: Multi-wavelength anomalous diffraction (MAD) has been used to determine the structure of the regulatory enzyme of de novo synthesis of purine nucleotides, glutamine 5-phosphoribosyl-1-pyrophosphate (PRPP) amidotransferase, from Bacillus subtilis.
Abstract: Multi-wavelength anomalous diffraction (MAD) has been used to determine the structure of the regulatory enzyme of de novo synthesis of purine nucleotides, glutamine 5-phosphoribosyl-1-pyrophosphate (PRPP) amidotransferase, from Bacillus subtilis. This allosteric enzyme, a 200-kilodalton tetramer, is subject to end product regulation by purine nucleotides. The metalloenzyme from B. subtilis is a paradigm for the higher eukaryotic enzymes, which have been refractory to isolation in stable form. The two folding domains of the polypeptide are correlated with functional domains for glutamine binding and for transfer of ammonia to the substrate PRPP. Eight molecules of the feedback inhibitor adenosine monophosphate (AMP) are bound to the tetrameric enzyme in two types of binding sites: the PRPP catalytic site of each subunit and an unusual regulatory site that is immediately adjacent to each active site but is between subunits. An oxygen-sensitive [4Fe-4S] cluster in each subunit is proposed to regulate protein turnover in vivo and is distant from the catalytic site. Oxygen sensitivity of the cluster is diminished by AMP, which blocks a channel through the protein to the cluster. The structure is representative of both glutamine amidotransferases and phosphoribosyltransferases.

Journal ArticleDOI
TL;DR: The continual reassessment method for phase I cancer trials provides improved estimation of the maximum tolerated dose, and fewer patients receive ineffective dose levels compared to the traditionally used design, and the CRM with modification outperforms the traditional method in a simulation study.
Abstract: The continual reassessment method (1) (CRM) for phase I cancer trials provides improved estimation of the maximum tolerated dose (MTD), and fewer patients receive ineffective dose levels compared to the traditionally used design. However, the CRM has not gained acceptance in practice owing to concerns with administering dose levels that are too toxic. In this article, several conservative modifications of the CRM are introduced. The result is a procedure that improves estimation of the MTD and decreases the use of ineffective doses, without significantly increasing the use of toxic dose levels. The CRM with modification outperforms the traditional method in a simulation study.

Journal ArticleDOI
TL;DR: Primary care physicians may benefit from screening tools and consultations by mental health specialists to assist in recognition and diagnosis of anxiety symptoms and disorders alone and mixed with depression.
Abstract: Background: Untreated anxiety may be particularly difficult for primary care physicians to recognize and diagnose because there are no reliable demographic or medical profiles for patients with this condition and because these patients present with a high rate of comorbid psychological conditions that complicate selection of treatment. Method: A prospective assessment of untreated anxiety symptoms and disorders among primary care patients. Results: Approximately 10% of eligible patients screened in clinic waiting rooms of a mixed-model health maintenance organization reported elevated symptoms and/or disorders of anxiety that were unrecognized and untreated. These patients with untreated anxiety reported significantly worse functioning on both physical and emotional measures than "not anxious" comparison patients; in fact these patients reported reduced functioning levels within ranges that would be expected for patients with chronic physical diseases, such as diabetes and congestive heart failure. The most severe reductions in functioning were reported by untreated patients whose anxiety was mixed with depression symptoms or disorders. Conclusion: Primary care physicians may benefit from screening tools and consultations by mental health specialists to assist in recognition and diagnosis of anxiety symptoms and disorders alone and mixed with depression.

Journal ArticleDOI
15 Apr 1994-Science
TL;DR: A monoclonal antibody that blocked uptake of cephalexin was used to identify and clone a gene that encodes an approximately 92-kilodalton membrane protein that was associated with the acquisition of peptide transport activity by transport-deficient cells.
Abstract: The first step in oral absorption of many medically important peptide-based drugs is mediated by an intestinal proton-dependent peptide transporter. This transporter facilitates the oral absorption of beta-lactam antibiotics and angiotensin-converting enzyme inhibitors from the intestine into enterocytes lining the luminal wall. A monoclonal antibody that blocked uptake of cephalexin was used to identify and clone a gene that encodes an approximately 92-kilodalton membrane protein that was associated with the acquisition of peptide transport activity by transport-deficient cells. The amino acid sequence deduced from the complementary DNA sequence of the cloned gene indicated that this transport-associated protein shares several conserved structural elements with the cadherin superfamily of calcium-dependent, cell-cell adhesion proteins.

Patent
14 Dec 1994
TL;DR: In this paper, a bis-indolemaleimide macrocycle derivatives of the formula were provided for inhibiting protein Kinase C in mammals. And the authors further provided the preparation, pharmaceutical formulations and the methods of use for inhibited protein kinase C.
Abstract: This invention provides novel bis-indolemaleimide macrocycle derivatives of the formula: ##STR1## The invention further provides the preparation, pharmaceutical formulations and the methods of use for inhibiting Protein Kinase C in mammals.

Journal ArticleDOI
TL;DR: It is hypothesized that the functional innervation of postmigratory granule neurons during cerebellar development may prevent further elimination of these neurons by blocking their programmed death.

Journal Article
TL;DR: Fluoxetine was well tolerated and appeared to be safe therapy for the treatment of obesity with efficacy demonstrated for 28 weeks, and two sites demonstrated greater efficacy than the study as a whole.
Abstract: Fluoxetine hydrochloride (Lovan, Eli Lilly and Company, Indianapolis, Indiana, USA), a specific serotonin uptake inhibitor, was compared with placebo in 458 obese outpatients in a 52-week double-blind randomized ten-site trial to study its effect on weight reduction. Patients in the fluoxetine and placebo groups were predominantly Caucasian (81% and 85%, respectively) and female (81% and 79%, respectively), with a mean body mass index (BMI) of 36.2 and 35.8 kg/m2, respectively, and a mean age of 43 years (both groups). Fluoxetine therapy (60 mg/day) resulted in statistically significantly (P 40 kg/m2) attained and maintained a greater weight loss than patients with lower baseline BMIs (< 40 kg/m2). Two sites demonstrated greater efficacy than the study as a whole. The use of nutrition counselling at one site and behaviour modification at the other, or other site-to-site differences, may account for the improved efficacy. Fluoxetine was well tolerated and appeared to be safe therapy for the treatment of obesity with efficacy demonstrated for 28 weeks.

Journal ArticleDOI
TL;DR: Data support the hypothesis of increased corticotropin releasing factor drive in the evening in depressed subjects and are in agreement with the longstanding observation of "early escape" from dexamethasone suppression between 4 and 11 PM in depressed patients.
Abstract: Objective: To determine whether depressed patients demonstrate hypothalamic-pituitary-adrenal (HPA) axis activation during the late afternoon and evening, a time when the HPA axis is usually quiescent in normal subjects. Methods: We administered metyrapone, an 11-βhydroxylase inhibitor of cortisol synthesis, to normal controls and depressed patients between 4 and 10 PM. Metyrapone blockade of cortisol secretion would amplify any HPA axis secretion. Results: In 10 normal control subjects, administration of metyrapone lowered plasma cortisol levels to a mean of 36 nmol/L. No rebound corticotropin or β-endorphin secretion was seen in these normal controls between 4 and 10PM, supporting the existence of a period of minimal endogenous corticotropin releasing factor drive. Compared with a group of placebo-treated depressed patients (n=10), metyrapone-treated depressed subjects (n=17) had significantly decreased plasma cortisol concentrations. However, in contrast to normal controls treated with metyrapone, metyrapone-treated depressed patients demonstrated rebound corticotroph secretion, particularly between 7:30 and 10PM( P =.036 for patients vs normal controls for β-endorphin secretion from 4:30 to 10PM). Conclusion: These data support the hypothesis of increased corticotropin releasing factor drive in the evening in depressed subjects and are in agreement with the longstanding observation of "early escape" from dexamethasone suppression between 4 and 11 PM in depressed patients.

Journal Article
TL;DR: Reverse transcription-polymerase chain reaction studies revealed human 5-HT2B receptor mRNA to be expressed in many tissues, including the central nervous system, and raises the possibility that the 5- HT2B receptors may be of significance in higher brain function.
Abstract: Clones encoding a portion of the human 5-hydroxytryptamine (5-HT)2B receptor gene were isolated from a human placental genomic library. Based on distribution studies of 5-HT2B receptor mRNA, human uterus cDNA libraries were constructed and screened, resulting in the isolation of several full-length cDNA clones. These clones harbored a common single open reading frame encoding a protein of 481 amino acids. The deduced amino acid sequence of the human 5-HT2B receptor displayed 91.5% identity within the transmembrane domains and 82% identity overall with the rat 5-HT2B receptor. The human 5-HT2B receptor stably expressed in AV12-664 cells demonstrated high affinity (Kd = 10.18 +/- 1.60 nM), saturable [3H]serotonin binding, similar to that previously described for the rat 5-HT2B receptor. The pharmacological profile of the human 5-HT2B receptor was virtually identical to that of the rat 5-HT2B receptor, with the exceptions of the 5-HT2A receptor antagonists ketanserin and spiperone. Both compounds exhibited higher affinity at the human 5-HT2B receptor (ketanserin, Ki = 376 +/- 58 nM; spiperone, Ki = 697 +/- 54 nM) than at the rat 5-HT2B receptor (ketanserin, Ki = 3559 +/- 175 nM; spiperone, Ki = 3278 +/- 92 nM). Functional coupling of the human 5-HT2B receptor was also demonstrated in AV12-664 cells, where 5-HT produced a dose-dependent increase in phosphatidylinositol hydrolysis (EC50 = 27 +/- 12 nM) analogous to that seen with the rat 5-HT2B receptor. Reverse transcription-polymerase chain reaction studies revealed human 5-HT2B receptor mRNA to be expressed in many tissues, including the central nervous system. The presence of 5-HT2B receptor mRNA in human brain and not in rat brain raises the possibility that the 5-HT2B receptor may be of significance in higher brain function.

Journal Article
TL;DR: The present data are consistent with the interpretation that xanomeline is a novel muscarinic receptor agonist with functional selectivity for M1 mus carinic receptors both in vitro and in vivo.
Abstract: Xanomeline [3(3-hexyloxy-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1- methylpyridine] has been evaluated as a muscarinic receptor agonist. In vitro, xanomeline had high affinity for muscarinic receptors in brain homogenates, but had substantially less or no affinity for a number of other neurotransmitter receptors and uptake sites. In cells stably expressing genetic m1 receptors, xanomeline increased phospholipid hydrolysis in CHO, BHK and A9 L cells to 100, 72 and 55% of the nonselective agonist carbachol. In isolated tissues, xanomeline had high affinity for M1 receptors in the rabbit vas deferens (IC50 = 0.006 nM), low affinity for M2 receptors in guinea pig atria (EC50 = 3 microM), was a weak partial agonist in guinea pig ileum and was neither an agonist nor antagonist in guinea pig bladder. In vivo, xanomeline increased striatal levels of dopamine metabolites, presumably by acting at M1 heteroreceptors on dopamine neurons to increase dopamine release. In contrast, xanomeline had only a relatively small effect on acetylcholine levels in brain, indicating that it is devoid of actions at muscarinic autoreceptors. In the gastrointestinal tract, xanomeline inhibited small intestinal and colonic motility, but increased small intestinal transmural potential difference. In contrast to the nonselective muscarinic agonist oxotremorine, xanomeline did not produce salivation, tremor nor hypothermia; it did, however, increase heart rate. The present data are consistent with the interpretation that xanomeline is a novel muscarinic receptor agonist with functional selectivity for M1 muscarinic receptors both in vitro and in vivo.

Journal ArticleDOI
TL;DR: Basic knowledge of the role of specific mGluRs in CNS function and pathologies will further expand in the near future, providing the framework for the discovery of novel pharmacological approaches to modulate excitatory amino acid neuronal transmission.

Journal Article
TL;DR: Anxiety in major depression does not appear to affect response to an antidepressant, and antidepressant selection should be determined by an agent's overall risk:benefit ratio, not the presence or absence of anxiety.
Abstract: BACKGROUND: The presence or absence of anxiety has traditionally determined choice of an antidepressant ("activating" or "sedating"); however, there is little scientific support for the construct. We conducted a meta-analysis to determine whether comorbid anxiety affected efficacy or predisposed patients to specific adverse events. METHOD: Data were evaluated from 19 randomized, double-blind clinical trials comparing fluoxetine with placebo or a tricyclic antidepressant (TCA) or both in 3,183 patients with major depression (Cochran-Mantel-Haenszel, Mantel-Haenszel incidence difference, analysis of variance, and Pearson's chi-square methods). On the basis of the anxiety/somatization factor within the 21-item Hamilton Rating Scale for Depression (HAM-D21), patients were characterized as anxious (score > or = 7) or nonanxious (score < 7). RESULTS: Fluoxetine was significantly (p < or = .05) more effective than placebo in treating both anxious and nonanxious major depression (mean improvement in HAM-D21 total score, 11.0 versus 8.1 and 8.1 versus 5.5, respectively). Fluoxetine was also statistically significantly more effective than placebo in reducing the HAM-D21 anxiety/somatization factor score (anxious, all patients). The efficacy of fluoxetine and TCAs was comparable (all measures, all groups). Discontinuations for adverse events were statistically significantly higher with fluoxetine than placebo (anxious, 15.2% versus 3.8%; nonanxious, 13.2% versus 6.7%) and with TCAs than fluoxetine (anxious, 28.9% versus 15.5%; nonanxious, 34.1% versus 19.0%). Among events suggestive of "activation" or "sedation," incidence rates ranged from 0.0% to 32.9%; discontinuation rates were low (0.0% to 4.1%), except for somnolence with TCAs (9.4% to 13.2%). CONCLUSION: Anxiety in major depression does not appear to affect response to an antidepressant. Therefore, antidepressant selection should be determined by an agent's overall risk:benefit ratio, not the presence or absence of anxiety.

Journal ArticleDOI
TL;DR: The rationale, design, and analysis of a recently completed adaptive trial addressing the use of an adaptive allocation scheme, a delayed response, and a surrogate response and a frequentist randomization analysis are described.
Abstract: Adaptive clinical trials have attracted the attention of statisticians because they allow for information accrued early in the trial to influence the allocation of treatment of later enrolled patients, thus allowing those patients an increased likelihood of receiving the better treatment. Few adaptive clinical trials have been reported in the literature; the purpose of this article is to describe the rationale, design, and analysis of a recently completed adaptive trial. Simulations to address sample size issues are presented. A Bayesian and a frequentist randomization analysis are discussed. The randomization analysis addresses the use of an adaptive allocation scheme, a delayed response, and a surrogate response. In this trial, the differences between the Bayesian and randomization inference were small. Some suggestions for future implementation of adaptive clinical trials and future research areas are provided.