The pituitary glycoprotein hormones, luteinizing hormone and follicle-stimulating hormone (FSH), act through their cognate receptors to initiate a series of coordinated physiological events that results in germ cell maturation. Given the importance of FSH in regulating folliculogenesis and fertility, the development of FSH mimetics has been sought to treat infertility. Currently, purified and recombinant human FSH are the only FSH receptor (FSH-R) agonists available for infertility treatment. By screening unbiased combinatorial chemistry libraries, using a cAMP-responsive luciferase reporter assay, we discovered thiazolidinone agonists (EC50's = 20 μm) of the human FSH-R. Subsequent analog library screening and parallel synthesis optimization resulted in the identification of a potent agonist (EC50 = 2 nm) with full efficacy compared with FSH that was FSH-R-selective and -dependent. The compound mediated progesterone production in Y1 cells transfected with the human FSH-R (EC50 = 980 nm) and estradiol production from primary rat ovarian granulosa cells (EC50 = 10.5 nm). This and related compounds did not compete with FSH for binding to the FSH-R. Use of human FSH/thyroid-stimulating hormone (TSH) receptor chimeras suggested a novel mechanism for receptor activation through a binding site independent of the natural hormone binding site. This study is the first report of a high affinity small molecule agonist that activates a glycoprotein hormone receptor through an allosteric mechanism. The small molecule FSH receptor agonists described here could lead to an oral alternative to the current parenteral FSH treatments used clinically to induce ovarian stimulation for both in vivo and in vitro fertilization therapy.

The design, synthesis, characterization, and screening of a large, encoded thiazolidinone library are described. Three sets of 35 building blocks were combined by encoded split-pool synthesis to give a library containing more than 42 000 members. Building block selection was based in part on a novel small molecule follicle stimulating hormone receptor agonist hit and in part for diversity. HPLC/MS techniques were applied at the single-bead level to build confidence in the reliability of library construction. Application of two distinct screening strategies resulted in the identification of compounds with significantly improved potency over the initial hit. This work demonstrates the versatility of encoded libraries for preparing a large number of analogues of a given hit while simultaneously generating a large collection of compounds for screening against other targets.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Pharmaceutical research and imaging science are becoming increasingly intertwined. Positron emission tomography (PET) is a molecular imaging technique with particularly broad application in drug discovery and development. At the same time, modern techniques of drug discovery are helping accelerate the development of new PET probes. This article describes the relationship between the two fields, with particular consideration of practical and strategic limitations to full utilization of available technology.

A novel synthetic stratetegy for compounds labeled with the positron-emitting isotope carbon-11 is described. The use of precursors attached to a solid support via safety-catch linkers allows selective release of radiolabeled material, leaving unreacted precursor attached to the support. Two different linkers demonstrate the application to the preparation of radiolabeled N-alkyl tertiary amines and N-alkylsulfonamides. This technique is expected to lead to more widespread use of positron emission tomography for the in vivo analysis of compound behavior.

Optimized methods for utilizing and analyzing dialkylamine tags in encoded combinatorial chemistry are reported. A previously described LC/fluorescence method has been shortened from over 1 h to 6 min. A novel ion exchange LC/MS method for decoding has been developed which is both fast and rugged. The use of quantitative encoding schemes is described. These new techniques have allowed a simplified, automated sample preparation scheme, and over 300 encoded bead samples can be read in a day.

A sensitive lawn-based format has been developed to screen bead-tethered combinatorial chemical libraries for antimicrobial activity. This method has been validated with beads linked to penicillin V via a photocleavable chemical linker in several analyses including a spike-and-recover experiment. The lawn-based screen sensitivity was modified to detect antibacterial compounds of modest potency, and a demonstration experiment with a naive combinatorial library of over 46,000 individual triazines was evaluated for antibacterial activity. Numerous hits were identified, and both active and inactive compounds were resynthesized and confirmed in traditional broth assays. This demonstration experiment suggests that novel antimicrobial compounds can be easily identified from very large combinatorial libraries of small, nonpeptidic compounds.

The authors describe an approach for quality control of a combinatorial library produced by encoded spit-pool synthesis. After the synthesis, they randomly select individual beads and cleave off the product. The authors used capillary high performance liquid chromatography (HPLC) with both UV-absorbance and electrospray mass spectrometry (MS) detection to identify the product from a single bead. After anlyzing the product with HPLC-MS, they cleaved the dialkylamine tags used to record the synthesis steps from the bead and decoded them by HPLC with fluorescence detection. The authors also compared the observed and expected products products to evaluate the quality of the library

We compared the beta 1-selective adrenoceptor antagonists bisoprolol and atenolol in a double-blind, randomized crossover study. After 4 weeks placebo phase, 59 patients with essential hypertension received either 10 mg bisoprolol or 50 mg atenolol once daily for 8 weeks, increased if necessary (target BP < or = 150/90 mmHg) to 20 and 100 mg, respectively, after 4 weeks. After a second placebo phase, crossover occurred to the alternative drug. We measured resting systolic and diastolic blood pressures and heart rate at 24 h post-dose baseline and after 4 and 8 weeks treatment. Both drugs significantly lowered systolic and diastolic blood pressures and heart rate at 8 weeks compared to baseline (all p < 0.05). Bisoprolol reduced heart rate significantly more than atenolol (p < 0.01), but systolic and diastolic blood pressure changes were not different between the two drugs. There was no difference in patient acceptability of the drugs as assessed by visual analogue scale. Despite theoretical and circumstantial evidence to suggest superiority of bisoprolol over atenolol, no significant difference between the two was found except for greater heart rate reduction with bisoprolol.

Xamoterol is a novel partial agonist of β1 adrenoceptors that reduces myocardial ischaemia and improves ventricular function in patients with mild to moderate heart failure. In a double blind, randomised, placebo controlled study, the effects of xamoterol given in a dose of 200 mg twice daily were studied in 51 consecutive patients with acute myocardial infarction, including 17 receiving diuretics for left ventricular failure. Treatment was started on the third day of admission and continued for 7 days. Blood pressure was recorded at 0900 daily, and 24 hour ambulatory electrocardiogram monitoring was commenced at this time on days 1 (pre-treatment), 4, 6 and 9 of admission. Additional drug therapy was recorded daily throughout the study. One patient died prior to randomisation and three were withdrawn (1 placebo, 2 xamoterol) with ventricular arrhythmias and/or disturbances of conduction. Compared to placebo, xamoterol had no effect on the rate of ventricular premature beats or ventricular tachycardia. Xamoterol increased nocturnal heart rate (0000–0600 hrs 79 ± 2; placebo 72 ± beats/min; P<0.03) but did not change blood pressure. Three patients receiving xamoterol, and 7 on placebo, required new (after randomisation) antianginal therapy. One patient treated with placebo developed new heart failure. These results show that xamoterol can be administered safely to selected patients following myocardial infarction, including those treated for mild heart failure.

This study reports the effects of the new β1 adrenoceptor partial agonist, xamoterol, on neuroendocrine activity after acute myocardial infarction (AMI). Fifty-one consecutive patients with AMI were randomized to treatment with xamoterol, 200 mg twice a day, or placebo; patients were also stratified as to whether or not diuretic therapy was given for left ventricular dysfunction. Noradrenalin, plasma renin activity (PRA), and atrial natriuretic factor (ANF) were measured over a 10-day period. Noradrenalin concentrations are higher (p < 0.05) in patients treated with diuretics at the time of admission and fell over the subsequent 10 days (p < 0.01). Treatment with xamoterol did not affect this noradrenalin response to myocardial infarction. PRA was also significantly higher in the patients treated with diuretics, and there was a nonsignificant trend for xamoterol to blunt the PRA response in these patients. There was no difference in ANF levels between those patients who were treated with diuretics and those who were not; xamoterol did not affect ANF. Thus xamoterol does not further elevate noradrenalin levels as do conventional beta blockers, and it does not activate the renin-angiotensin system as do potent nonselective beta agonists. Furthermore, xamoterol does not increase ANF levels, probably because it is not negatively inotropic. We conclude that xamoterol does not cause deleterious neuroendocrine changes in patients with AMI even in those treated for heart failure.

The efficacy of pharmacotherapy for smoking cessation is well documented. However, due to relapse rates and side effects, hypnotherapy is gaining attention as an alternative treatment option. The aim of this one-center randomized study was to compare the efficacy of hypnotherapy alone, as well as hypnotherapy with nicotine replacement therapy (NRT), to conventional NRT in patients hospitalized with a cardiac or pulmonary illness.We evaluated self-reported and biochemically verified 7-day prevalence smoking abstinence rates at 12 and 26 weeks post-hospitalization. Patients (n = 164) were randomized into one of three counseling-based treatment groups: NRT for 30 days (NRT; n = 41), a 90-min hypnotherapy session (H; n = 39), and NRT with hypnotherapy (HNRT; n = 37). Treatment groups were compared to a “self-quit” group of 35 patients who refused intervention.Hypnotherapy patients were more likely than NRT patients to be nonsmokers at 12 weeks (43.9% vs. 28.2%; p = 0.14) and 26 weeks after hospitalization (36.6% vs. 18.0%; p = 0.06). Smoking abstinence rates in the HNRT group were similar to the H group. There was no difference in smoking abstinence rates at 26 weeks between “self quit” and participants in any of the treatment groups. In multivariable regression analysis adjusting for diagnosis and demographic characteristics, H and HNRT were over three times more likely than NRT participants to abstain at 26-weeks post-discharge (RR = 3.6; p = 0.03 and RR = 3.2; p = 0.04, respectively).Hypnotherapy is more effective than NRT in improving smoking abstinence in patients hospitalized for a smoking-related illness, and could be an asset to post-discharge smoking cessation programs.

Bevantolol is a novel β 1-selective beta-adrenoceptor antagonist. The Study Group evaluated its therapeutic utility (100-300 mg bid) compared with pro pranolol (80-240 mg bid) in 266 patients with mild to moderate essential hyper tension (WHO Grades I and II, sitting diastolic blood pressure (DBP) ≥ 95 mmHg). There was no difference in their antihypertensive efficacy over six months, 77% being controlled (DBP ≤ 90 mmHg) on bevantolol and 81 % on propranolol. Hydrochlorothiazide 25-50 mg bid added later improved BP con trol in those incompletely controlled on bevantolol monotherapy. Both β- adrenoceptor antagonists also reduced intraocular pressure. Bevantolol caused significantly fewer adverse effects than propranolol with many fewer with drawals during long-term therapy. This unique clinical pharmacologic profile of bevantolol enhances its therapeutic usefulness and may relate to alpha-adreno ceptor antagonist activity, as well as to its β1-selectivity.

This report describes the relationship between the intensity of early inflammation after acute myocardial infarction and the later thickness of the left ventricular (LV) scar. Histologic sections of hearts from methylprednisolone-treated (MP), cobra venom factor-treated (CVF), and untreated control rats that had been subjected to either 2 or 21 days of coronary artery occlusion were studied. In the rats examined at 2 days (n=20 for MP, n=16 for CVF, and n=20 for controls), a semiquantitative inflammation score (1–4) was attributed to each infarct. Mononuclear (MN) cells were counted in 4 oil-immersion fields per section and polymorphonuclear (PMN) cells in 9 oil-immersion fields per section. In the rats examined at 21 days (n=22 for MP, n=22 for CVF, and n=26 for controls), the thickness of the LV scar was measured every 1.6 mm along its circumference. Inflammation scores at 2 days were 3.5±.6 for controls, 1.5±.5 for MP, and 2.9±.8 for CVF (p<.05 among groups). The MN cells counted were 73±7 for controls, 47±5 for MP, and 61±9 for CVF (p<.05 among groups). There was no difference in PMN infiltrate among groups. Scar thickness at 21 days were .9±.1 mm for controls, .7±.1 mm for MP, and .9±.1 mm for CVF (MP compared to CVF and controls, p<.01).

This report describes early and later structural changes that occur in infarcted and noninfarcted ventricular myocardium after coronary arterial ligation in the rat. Histologic analysis was conducted of hearts subjected to 2 days (n = 22) and 21 days (n = 22) of coronary arterial occlusion, or to a sham operation (n = 22). Lengths, circumferences and areas of the left ventricle, of infarcted myocardium and of noninfarcted myocardium were obtained by videoplanimetry. Although the left ventricular (LV) endocardial circumference was similarly increased at 2 days (19 ± 3 mm, mean ± standard deviation) and 21 days (20 ± 3 mm) compared with shams (13 ± 3 mm, p <0.01), LV epicardial circumference was similar in all 3 groups (30 ± 2, 31 ± 2 and 31 ± 2 mm, respectively). The area enclosed by the endocardial circumference was significantly (p <0.01) increased at 2 days (20 ± 6 mm2) and 21 days (22 ± 6 mm2) compared with shams (7 ± 4 mm2); however, the area enclosed by the epicardial circumference was similar at 2 days, 21 days and in shams (70 ± 9, 72 ± 9 and 73 ± 10 mm2, respectively). The total LV tissue area was similar at 2 and 21 days, but was less than that in shams (p <0.01). Between 2 and 21 days, 3 measures of infarcted myocardium significantly decreased: its segments of endocardial and epicardial circumference, its circumference and its area. Between 2 and 21 days, 4 measures of noninfarcted myocardium significantly increased: septal length, LV free wall length, right ventricular length and area. Therefore, early (within 2 days) structural changes after acute myocardial infarction consist of LV tissue loss, presumably along the infarcted subendocardium, concomitant with LV cavity dilation; later (between 2 and 21 days) changes consist of contraction of infarcted tissue with compensatory expansion (hypertrophy) of noninfarcted tissue.

The factors that determine the thickness of transmural myocardial infarcts are unknown. Therefore, the relation between the size and thickness of transmural infarcts in 67 rats 21 days after occlusion of the left main coronary artery was studied. On examination of histologic sections, infarct size was determined by planimetry and expressed as a percentage of the left ventricular (LV) area, and thickness was expressed as a percentage of noninfarcted ventricular septal wall thickness. The circumferential length of the infarcted ventricle was measured in millimeters, as well as the circumferential length of the noninfarcted ventricular septum. Septal wall thickness was similar in rats with transmural infarcts and in sham-operated rats. No significant correlation was observed between infarct size and thickness (r = 0.10) or between circumferential length of the infarct and infarct thickness (r = 0.17). However, large (greater than or equal to 20% of the left ventricle, n = 37) and small (less than 20% of the left ventricle, n = 30) infarcts which were similarly thin (37 +/- 1% and 34 +/- 2% of septal wall thickness, respectively) affected LV topography differently. Large infarcts resulted in a 23% greater loss of myocardium (p less than 0.001), greater expansion of the LV cavity (18 +/- 9 mm2 compared with 14 +/- 1 mm2 in small infarcts, p less than 0.005), and lengthening of the septal wall (7.2 +/- 1.1 mm and 6.7 +/- 1.0 mm in large and small infarcts, respectively [p less than 0.05], and 6.3 +/- 0.1 mm in shams). Increase in cavity area and septal length in infarcted ventricles suggested a volume overload hypertrophy, which at 3 weeks was nonetheless inadequate to provide as much normal muscle as was present in sham-operated rats. In an additional 9 rats with subendocardial infarctions (involving less than 75% of the LV wall from endocardium to epicardium), the LV walls were thicker (94 +/- 5% of septal wall thickness, compared with 35 +/- 1% for transmural infarcts, p less than 0.001) and an inverse correlation was observed between infarct size and thickness. In conclusion, neither the size of a transmural infarct in rat nor the circumferential length of infarction determines the thickness of the infarct; however, infarct size does affect LV topography by increasing LV cavity area and the length of the noninfarcted septal wall. Subendocardial infarcts result in less myocardial thinning than do transmural infarcts.

Journal Article Identification and quantification of histochemical border zones during the evolution of myocardial infarction in the rat Get access MICHAEL C FISHBEIN, MICHAEL C FISHBEIN * From the departments of Pathology and Medicine, Peter Bent Brigham Hospital and the Harvard Medical School, Boston, Massachusetts 02115, and the Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California 90048 *Address for reprints: Michael C Fishbein, MD, Department of Pathology, Cedars-Sinai Medical Center, 8700 Beverly Boulevard Los Angeles, California 90048, USA. Search for other works by this author on: Oxford Academic PubMed Google Scholar CAROL A HARE, CAROL A HARE From the departments of Pathology and Medicine, Peter Bent Brigham Hospital and the Harvard Medical School, Boston, Massachusetts 02115, and the Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California 90048 Search for other works by this author on: Oxford Academic PubMed Google Scholar SALLY A GISSEN, SALLY A GISSEN From the departments of Pathology and Medicine, Peter Bent Brigham Hospital and the Harvard Medical School, Boston, Massachusetts 02115, and the Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California 90048 Search for other works by this author on: Oxford Academic PubMed Google Scholar JOEL SPADARO, JOEL SPADARO From the departments of Pathology and Medicine, Peter Bent Brigham Hospital and the Harvard Medical School, Boston, Massachusetts 02115, and the Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California 90048 Search for other works by this author on: Oxford Academic PubMed Google Scholar DEREK MACLEAN, DEREK MACLEAN From the departments of Pathology and Medicine, Peter Bent Brigham Hospital and the Harvard Medical School, Boston, Massachusetts 02115, and the Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California 90048 Search for other works by this author on: Oxford Academic PubMed Google Scholar PETER R MAROKO PETER R MAROKO From the departments of Pathology and Medicine, Peter Bent Brigham Hospital and the Harvard Medical School, Boston, Massachusetts 02115, and the Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, California 90048 Search for other works by this author on: Oxford Academic PubMed Google Scholar Cardiovascular Research, Volume 14, Issue 1, January 1980, Pages 41–49, https://doi.org/10.1093/cvr/14.1.41 Published: 01 January 1980