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The ATPase subunit of DNA gyrase B is an attractive antibacterial target due to high conservation across bacteria and the essential role it plays in DNA replication. A novel class of pyrazolopyridone inhibitors was discovered by optimizing a fragment screening hit scaffold using structure guided design. These inhibitors show potent Gram-positive antibacterial activity and low resistance incidence against clinically important pathogens.

The emergence and spread of multidrug resistant bacteria are widely believed to endanger human health. New drug targets and lead compounds exempt from cross-resistance with existing drugs are urgently needed. We report on the discovery of azaindole ureas as a novel class of bacterial gyrase B inhibitors and detail the story of their evolution from a de novo design hit based on structure-based drug design. These inhibitors show potent minimum inhibitory concentrations against fluoroquinolone resistant MRSA and other Gram-positive bacteria.

Antibacterials with a novel mechanism of action offer a great opportunity to combat widespread antimicrobial resistance. Bacterial DNA Gyrase is a clinically validated target. Through physiochemical property optimization of a pyrazolopyridone hit, a novel class of GyrB inhibitors were discovered. Guided by structure-based drug design, indazole derivatives with excellent enzymatic and antibacterial activity as well as great animal efficacy were discovered.

Objective: To investigate the psychometric and structural properties of the Five Facets Mindfulness Questionnaire (FFMQ) among meditators, to develop a short form, and to examine associations of mindfulness with mental health and the mechanisms of mindfulness., Methods: Two independent samples were used, a German (n = 891) and a Spanish (n = 393) meditator sample, practicing various meditation styles. Structural and psychometric properties of the FFMQ were investigated with multigroup confirmatory factor analysis and exploratory structural equation modeling. Associations with mental health and mechanisms of mindfulness were examined with path analysis., Results: The derived short form broadly matched a previous item selection in samples of non-meditators. Self-regulated Attention and Orientation to Experience governed the facets of mindfulness on a higher-order level. Higher-order factors of mindfulness and meditation experience were negatively associated with symptoms of depression and anxiety, and perceived stress. Decentering and nonattachment were the most salient mechanisms of mindfulness. Aspects of emotion regulation, bodily awareness, and nonattachment explained the effects of mindfulness on depression and anxiety., Conclusions: A two-component conceptualization for the FFMQ, and for the study of mindfulness as a psychological construct, is recommended for future research. Mechanisms of mindfulness need to be examined in intervention studies.

Atomic mutagenesis has emerged as a powerful tool to unravel specific interactions in complex RNA molecules. An early extensive study of analogs of the exogenous guanosine nucleophile in group I intron self-splicing by Bass and Cech demonstrated structure-function relationships analogous to those seen for protein ligands and provided strong evidence for a well-formed substrate binding site made of RNA. Subsequent functional and structural studies have confirmed these interacting sites and extended our understanding of them, with one notable exception. Whereas 7-methyl guanosine did not affect reactivity in the original study, a subsequent study revealed a deleterious effect of the seemingly more conservative 7-deaza substitution. Here we investigate this paradox, studying these and other analogs with the more thoroughly characterized ribozyme derived from the Tetrahymena group I intron. We found that the 7-deaza substitution lowers binding by ~20-fold, relative to the cognate exogenous guanosine nucleophile, whereas binding and reaction with 7-methyl and 8-aza-7-deaza substitutions have no effect. These and additional results suggest that there is no functionally important contact between the N7 atom of the exogenous guanosine and the ribozyme. Rather, they are consistent with indirect effects introduced by the N7 substitution on stacking interactions and/or solvation that are important for binding. The set of analogs used herein should be valuable in deciphering nucleic acid interactions and how they change through reaction cycles for other RNAs and RNA/protein complexes.

Studies have shown the detection of emerging contaminants (ECs), of which pharmaceuticals are a subset, in surface waters across the United States. The objective of this study was to develop methods, and apply them, to evaluate the potential for food chain transfer when EC-containing waters are used for crop irrigation. Greenhouse experiments were performed in which select food crops were irrigated with water spiked with three antibiotics. Field experiments, at two different sites, were conducted. Select crops were irrigated with wastewater effluent known to contain ECs, EC-free well water, and Colorado River water containing trace-level ECs. The results of the greenhouse studies show the potential for uptake of one or more of the antibiotics evaluated, albeit at very low levels. In those food crops watered with wastewater effluent, only an industrial flavoring agent, N,N'-dimethylphenethylamine (DMPEA), was consistently found. None of the evaluated contaminants were found in crops irrigated with Colorado River water.

Low levels (ng/g) of musk ketone (MK), used as a fragrance additive in the formulation of personal care products, are frequently detected in the water and other environment. Thus, aquatic organisms can be continuously exposed to MK. In this study, kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite, bound to cysteine-hemoglobin (Hb) in rainbow trout, formed by enzymatic nitro-reduction of MK have been demonstrated. Trout were exposed to a single exposure of 0.010, 0.030, 0.10, and 0.30 mg MK/g fish. Twenty-seven Hb samples were collected from exposed- and control fish subsequent to exposure intervals of 1 d (24 h), 3 d (72 h), and 7 d (168 h). Basic hydrolysis released bound AMK metabolite was extracted into n-hexane and then concentrated and analyzed by gas chromatography (GC) electron capture negative ion chemical ionization (NICI) mass spectrometry (MS) using selected ion monitoring (SIM). The presence of the AMK metabolite in Hb extracts was confirmed by agreement of similar mass spectral features and retention time with a standard. In the dose-response study, maximum adduct formation was obtained at the 0.10 mg/g dose with an average AMK metabolite concentration of 2.2 ng/g. For kinetics, the highest concentration of the AMK metabolite was found to be 32.0 ng/g at 0.030 mg/g dose in 3-d sample. Further elimination of the metabolite showed kinetics with a half-life estimated to be 2 d, assuming first-order kinetics. The metabolite was not detected in the control samples, non-hydrolyzed Hb, and reagent blank extracts. The detection limit for AMK in the Hb was approximately 0.30 ng/g, based on a signal to noise ratio of 3 (S/N = 3).

A positive family history of coronary heart disease alone confers an increased risk, which may be affected by untreated hypercholesterolemia. Dietary counseling is a first-line treatment approach. To determine whether nurse counseling can provide additional benefits over usual physician efforts to lower dietary fat in high-risk persons, 117 apparently healthy adult siblings of persons with premature coronary heart disease were counseled by a registered nurse using adapted national guidelines. Reductions in total fat, saturated fat, and cholesterol were significantly greater in the nurse group compared to those in the usual care group. Total fat intake decreased by 14 g in the nurse group, compared with an increase of 5 g in the usual care group (p=0.0001). Assignment to the nurse group was also a significant predictor of a greater reduction in the percentage of total fat calories (p=0.008). The authors conclude that a registered nurse may serve as a complement to usual care in efforts to lower dietary fat and cholesterol in high-risk families. (c)2001 CHF, Inc.

Objective: The authors tested the impact on cardiovascular risk profiles of African American women ages 40 years and older after one year of participation in one of three church-based nutrition and physical activity strategies: a standard behavioral group intervention, the standard intervention supplemented with spiritual strategies, or self-help strategies., Methods: Women were screened at baseline and after one year of participation. The authors analyzed intention-to-treat within group and between groups using a generalized estimating equations adjustment for intra-church clustering. Because spiritual strategies were added to the standard intervention by participants themselves, the results from both active groups were similar and, thus, combined for comparisons with the self-help group., Results: A total of 529 women from 16 churches enrolled. Intervention participants exhibited significant improvements in body weight (-1.1 lbs), waist circumference (-0.66 inches), systolic blood pressure (-1.6 mmHg), dietary energy (-117 kcal), dietary total fat (-8 g), and sodium intake (-145 mg). The self-help group did not. In the active intervention group, women in the top decile for weight loss at one year had even larger, clinically meaningful changes in risk outcomes (-19.8 lbs)., Conclusions: Intervention participants achieved clinically important improvements in cardiovascular disease risk profiles one year after program initiation, which did not occur in the self-help group. Church-based interventions can significantly benefit the cardiovascular health of African American women.

Objective: To examine the comparative accuracy of telephone and in-person 24-hour dietary recall methods., Subjects: One hundred eighty-five African-American females, aged 40 years and older, recruited from Sunday church services in Baltimore City, Md., Methods: Participants were trained to estimate portion size with plastic food models and a 2-dimensional food recall booklet. Dietary intake was then assessed with 2 in-person 24-hour dietary recalls and 1 telephone 24-hour dietary recall, all using a computer-assisted, multiple pass approach. Results from the 2 in-person recalls were averaged and compared with the results from the telephone recall., Statistical Analyses: Cross-tabulation, paired t test, Pearson's correlation, chance-corrected agreement, and stepwise linear regression analyses were performed., Results: There were no significant differences between the telephone and in-person methods for any nutrient. Agreement between methods was moderate for all major dietary components, with corrected correlations between methods ranging from 0.26 to 0.97 (P<.001), and kappas ranging from 0.155 to 0.372 (P<.01). Levels of low-energy reporting were high (88% telephone, 91% in-person), though there were no significant differences between methods., Conclusions: The telephone 24-hour dietary recall method appears to be comparable to the standard in-person method among older African-American women. Portion-size training in person may make subsequent telephone dietary recalls acceptable in this population.

Protease inhibitors are very effective in treating patients infected with HIV. However, many drugs in this class penetrate poorly into the central nervous system (CNS) and may permit this site to be a sanctuary from which resistant virus can emerge. Previous studies have shown that the protease inhibitor saquinavir (SQV) interacts with the multidrug transport system, P-glycoprotein (P-gp), expressed in epithelial cells in the gut mucosa and at the blood-brain barrier, and thus might affect both the oral absorption and the penetration of SQV into the CNS. To determine whether SQV is a substrate for P-gp, its uptake was determined in cancer cells, which do (Dx5) and do not (MES-SA) express P-gp. The distribution of SQV between brain tissue and plasma was also investigated in rats and in normal and P-gp-deficient mdr1a(-/-) mice. The distribution ratio of SQV in plasma:brain:cerebrospinal fluid was approximately 100:10:0.2 in rats. The accumulation of SQV was enhanced in MES-SA cells (P-gp-negative) versus Dx5 cells (P-gp-positive). Bolus i.v. injection of [(14)C]SQV (2 and 5 mg/kg) into mdr1a(-/-) and normal mice (n = 3 or 4) resulted in 3-fold higher radioactivity in brains from mdr1a(-/-) mice. Similarly, oral administration of [(14)C]SQV (500 mg/kg) resulted in a 5-fold increase in systemic exposure and a 10-fold increase in brain levels in mdr1a(-/-) mice. These data demonstrate that saquinavir is a substrate for P-gp and that this transport system may play a role in limiting oral absorption and CNS exposure to this protease inhibitor.

Background: The Pl(A2) polymorphism of GPIIIa has been associated with unstable coronary syndromes in some studies, but the association has remained debated. None of the previous studies have focused on families at high risk. Risk factors tend to cluster within kindreds with high prevalence of premature coronary heart disease (CHD). Therefore, a heightened prevalence of the Pl(A2) polymorphism among siblings of patients with CHD would support the hypothesis that Pl(A2) is linked, directly or indirectly, to CHD., Objectives: To measure the prevalence of the Pl(A2) polymorphism among siblings of patients with CHD before the age of 60 years and to seek an association between the Pl(A2) polymorphism and established atherosclerotic and thrombogenic risk factors., Methods: From January 1994 to April 1996, we genotyped 116 asymptomatic siblings (60 Caucasians, 56 Afro-Caribbeans) of patients with CHD manifestations before the age of 60 years for the Pl(A) polymorphism (also called HPA-1). A control cohort was used for comparison, consisting of individuals that were matched for race and geographic area but were free of CHD (n = 268, 168 Caucasians and 100 Afro-Caribbeans). In addition, we have characterized the sibling cohort for other atherogenic and thrombogenic risk factors., Results: The prevalence of Pl(A2)-positive individuals (Pl(A2)[+], Pl(A1/A2) heterozygotes plus Pl(A2/A2) homozygotes) in the sibling cohort was high: 41.4%. When analyzed separately, the prevalence of Pl(A2)(+) siblings was 53.3% among Caucasians and 28.6% among Afro-Caribbeans. There was no association between Pl(A2) and other established atherogenic or thrombogenic risk factors. Interestingly, the clustering of other risk factors was lesser among Pl(A2)(+) siblings than their Pl(A1) counterparts., Conclusions: This study supports the hypothesis that the prevalence of Pl(A2)(+) individuals is high in kindreds with premature CHD. Hence, like the established risk factors that tend to cluster in families with premature CHD and contribute strongly to the accelerated atherosclerotic process affecting these individuals, the Pl(A2) polymorphism of GPIIIa may represent an inherited risk that promotes the thromboembolic complications of CHD. That these asymptomatic Pl(A2)(+) siblings had overall less established risk factors than their Pl(A1) counterparts might represent an explanation for why they remained asymptomatic despite their Pl(A2) positivity.

After their assembly in the nucleolus, ribosomal subunits are exported from the nucleus to the cytoplasm. After export, the 20S rRNA in the small ribosomal subunit is cleaved to yield 18S rRNA and the small 5' ITS1 fragment. The 5' ITS1 RNA is normally degraded by the cytoplasmic Xrn1 exonuclease, but in strains lacking XRN1, the 5' ITS1 fragment accumulates in the cytoplasm. Using the cytoplasmic localization of the 5' ITS1 fragment as an indicator for the export of the small ribosomal subunit, we have identified genes that are required for ribosome export. Ribosome export is dependent on the Ran-GTPase as mutations in Ran or its regulators caused 5' ITS1 to accumulate in the nucleoplasm. Mutations in the genes encoding the nucleoporin Nup82 and in the NES exporter Xpo1/Crm1 also caused the nucleoplasmic accumulation of 5' ITS1. Mutants in a subset of nucleoporins and in the nuclear transport factors Srp1, Kap95, Pse1, Cse1, and Mtr10 accumulate the 5' ITS1 in the nucleolus and affect ribosome assembly. In contrast, we did not detect nuclear accumulation of 5' ITS1 in 28 yeast strains that have mutations in other genes affecting nuclear trafficking.

Objectives: To determine if heart disease risk factors differentially affect lipoprotein(a) concentration by race, we assessed the association of lipoprotein(a) with heart disease risk factors in healthy Caucasians and African Americans with family histories of premature heart disease., Methods: Participants (403 Caucasian and 148 African American), all less than 60 years old and free of heart disease, were recruited through a brother or sister diagnosed with coronary heart disease before age 60. Risk factor information was elicited through an interview and medical examination., Results: As expected, lipoprotein(a) was significantly higher among African Americans than among Caucasians. Mean lipoprotein(a) concentrations were positively associated with smoking status and age, and negatively associated with hypertension in African Americans. Smokers had lipoprotein(a) levels 38% higher than nonsmokers. Conversely, lipoprotein(a) concentrations were unrelated to heart disease risk factors among Caucasians., Conclusion: While this study confirms that lipoprotein(a) concentration is independent of CHD risk factors in Caucasians, lipoprotein(a) appears to be related to several CHD risk factors in African Americans at high risk for premature heart disease. Given the high levels of lipoprotein(a) in people of African descent and lipoprotein(a)'s link to cardiovascular diseases, more research is needed to understand the relationship of lipoprotein(a) to heart disease risk factors and the subsequent disease in African-American populations.

The purpose of this study was to describe the scope of fatty food preferences of urban African American women and to examine factors associated with the selection of high fat foods. A volunteer sample of urban African American women church-goers were invited for dietary and risk factor screening at health fairs held following Sunday services. A standardized instrument, the Fat Intake Scale (FIS), was administered primarily by dietitians to estimate dietary fat intake and usual food choices. A sum score of 25 or more is thought to be associated with higher fat and cholesterol intake. As a validation of the FIS, a 24-hour recall was administered to a subsample. Sociodemographics, smoking status and comorbidity were assessed by self-report. Body weight, height, and total blood serum cholesterol were assessed using standardized measurement techniques. In the 521 participating women, 61% were classified as obese based on national reference norms for body mass index (BMI). More than 81% had an FIS of 25 or greater. On multiple logistic regression analysis, significant predictors of a higher fat diet (FIS > or = 25) included age greater than 45 years, obesity, and the absence of comorbidity. These findings suggest that there are independent predictors of selection of a diet high in fat. This has implications for planning and targeting community-based nutrition interventions for African American women who exhibit among the highest rates of obesity in the U.S. and who suffer an excess burden of obesity-related diseases.

Among persons with a family history of premature coronary heart disease (CHD), siblings bear an excess risk of CHD that is as high as 12 times that of the general population. Aggressive, new, national guidelines for CHD risk reduction have focused on high-risk families, yet little is known about actual remediable risk factors in siblings of persons with premature CHD. To determine the magnitude of the problem relative to the general population, we screened 846 unaffected siblings (ages 30 to 59 years) of persons with documented CHD before age 60 years and compared their risk factor values with population reference norms obtained in the Third National Health and Nutrition Examination Survey (NHANES III) and the National Health Interview Survey (NHIS). Mean levels of low-density lipoprotein cholesterol were 0.52 mmol/L (20 mg/dl) higher in siblings; the prevalence of low-density lipoprotein cholesterol > or =4.14 mmol/L (160 mg/dl) was nearly twice that of race, sex, and age-specific values from NHANES III. Levels of high-density lipoprotein cholesterol <0.91 mmol/L (35 mg/dl) were similar between siblings and NHANES III (11% and 12%, respectively). Only 4% of all siblings had triglyceride levels > or =4.52 mmol/L (400 mg/dl). Hypertension prevalence was twice as high among siblings as among the NHANES III. Current smoking was 33.9% in white siblings and 25.5% in the NHIS, whereas smoking in African-Americans was similar to that in the NHIS (31.1% vs 29.2%). A mere 13% to 29% of siblings were without any major remediable risk factors. The overwhelming need for risk factor modification in this easily identifiable high-risk population supports aggressive national guidelines and demonstrates the lack of adequate treatment of apparently healthy siblings of persons with premature CHD.

Of four systems available from the literature, based on cyclodextrins, dioctylsulfosuccinate, bile salts, and molecular micelles consisting of oligomers of undecylenic acid, the most successful separation system in our hands is based on the molecular micelles, oligomers of sodium undecylenic acid (OSUA). We have employed organic additives of acetonitrile, acetone, and tetrahydrofuran in achieving separations of polyaromatic hydrocarbons (PNAs) using molecular micelles. Generally, successful separations are achieved with 20-40% composition as the organic additive in an 8 mM borate buffer. We separated 16 PNAs with 20% tetrahydrofuran in a system of 8 mM borate and 0.125 g/10 mL (ca. 6.25 mM) of OSUA. Typical extracts of environmental samples contain additional analytes besides the typical 16 target compounds. Among these are the nitrogen-containing aromatics that can act as cations under conditions of low pH and additional compounds that can act as anions under basic conditions in free-zone electrophoresis. These additional classes of analytes are separated by capillary zone electrophoresis/laser-induced fluorescence detection using a frequency-doubled laser operated at 257 nm.

Background: Siblings of individuals with premature coronary heart disease have a high prevalence of low-density lipoprotein cholesterol (LDL-C) levels requiring treatment., Objective: To evaluate management strategies for high LDL-C levels in apparently healthy 30- to 59-year-old siblings of individuals with documented coronary heart disease prior to age 60 years., Methods: In a 2-year trial of care provided by either a nurse trained in lipid management (NURS) or enhanced primary care (EPC), in which physicians received recommendations based on national guidelines, 156 siblings with LDL-C levels of 4.14 mmol/L (160 mg/dL) were randomized by family. The LDL-C goal levels below 3.36 mmol/L (130 mg/dL) were compared between and within intervention groups. Multiple logistic regression analyses were applied to predict 2-year achievement of the goal., Results: The NURS group achieved a significantly greater percentage of goal LDL-C levels than the EPC group (26% vs 10%; P=.008). The NURS LDL-C levels decreased an average of 0.91 mmol/L (35 mg/dL) while EPC levels decreased by 0.52 mmol/L (24 mg/dL) (P=.09). In the final multivariate model, siblings taking lipid-lowering drug treatment were 6.02 times more likely (95% confidence interval, 2.24-16.18) than those not receiving pharmacotherapy to achieve LDL-C goals; nurse management (P=.09) was marginally significant. Pharmacotherapy was instituted in 45.2% of NURS and 16.7% of EPC siblings (P=.001)., Conclusions: High LDL-C levels in siblings were more effectively treated by a trained nurse, probably related to greater adherence to the application of national guidelines. Nonetheless, the majority of siblings with high LDL-C levels did not meet goal levels 2 years after an index case coronary heart disease event.

To determine the extent to which the Fifth Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC-V) guidelines were implemented in high-risk families with premature coronary heart disease, we examined the prevalence of hypertension and associated coronary risk factors in asymptomatic siblings of persons with documented premature coronary disease (<60 years of age). A total of 859 apparently healthy siblings (51% male, 19% African American) were screened for coronary risk factors. Siblings were classified as normotensive or hypertensive (BP > or = 140/90 and/or current antihypertensive pharmacotherapy). The prevalence of hypertension, awareness, treatment, and control among siblings was compared with published national estimates from the third National Health and Nutrition Examination Survey. The prevalence of hypertension in siblings was 44%. Among all hypertensives, only 60% were aware of being hypertensive, 45% were being treated, and 16% were under control. A high prevalence of other coronary risk factors was found among hypertensive siblings: 72% were hypercholesterolemic; 61% were obese; 29% were current smokers; 82% were consuming >30% of calories from fat; and only 14% were participating in vigorous physical activity three or more times per week. Comparisons with the national reference population revealed siblings to have a significantly higher prevalence of hypertension, along with significantly lower levels of awareness, treatment, and control. These findings demonstrate the intersection of multiple risk factors among hypertensive siblings and emphasize the need for more aggressive screening and treatment in this easily identifiable high-risk population.

1. Urinary bladder smooth muscle is enriched with muscarinic receptors, the majority of which are of the M2 subtype whereas the remaining minority belong to the M3 subtype. The objective of the present study was to assess the functional role of M2 and M3 receptors in the urinary bladder of rat in vitro and in vivo by use of key discriminatory antagonists. 2. In the isolated bladder of rat, (+)-cis-dioxolane produced concentration-dependent contractions (pEC50 = 6.3) which were unaffected by tetrodotoxin (0.1 microM). These contractions were antagonized by muscarinic antagonists with the following rank order of affinity (pA2) estimates: atropine (9.1) > 4-diphenyl acetoxy-methyl piperidine methiodide (4-DAMP) (8.9) > darifenacin (8.5) > para fluoro hexahydrosiladifenidol (p-F-HHSiD) (7.4) > pirenzepine (6.8) > methoctramine (5.9). These pA2 estimates correlated most favourably (r = 0.99, P < 0.001) with the binding affinity (pKi) estimates of these compounds at human recombinant muscarinic m3 receptors expressed in Chinese hamster ovary cells, suggesting that the receptor mediating the direct contractile responses to (+)-cis-dioxolane equates with the pharmacologically defined M3 receptor. 3. As M2 receptors in smooth muscle are negatively coupled to adenylyl cyclase, we sought to determine whether a functional role of M2 receptors could be unmasked under conditions of elevated adenylyl cyclase activity (i.e., isoprenaline-induced relaxation of KCl pre-contracted tissues). Muscarinic M3 receptors were preferentially alkylated by exposing tissues to 4-DAMP mustard (40 nM, 1 h) in the presence of methoctramine (0.3 microM) to protect M2 receptors. Under these conditions, (+)-cis-dioxolane produced concentration-dependent reversal (re-contraction) of isoprenaline-induced relaxation (pEC50 = 5.8) but had marginal effects on pinacidil-induced, adenosine 3':5'-cyclic monophosphate (cyclic AMP)-independent, relaxation. The re-contractions were antagonized by methoctramine and darifenacin, yielding pA2 estimates of 6.8 and 7.6, respectively. These values are intermediate between those expected for these compounds at M2 and M3 receptors and were consistent with the involvement of both of these subtypes. 4. In urethane-anaesthetized rats, the cholinergic component (approximately 55%) of volume-induced bladder contractions was inhibited by muscarinic antagonists with the following rank order of potency (ID35%inh, nmol kg-1, i.v.): 4-DAMP (8.1) > atropine (20.7) > methoctramine (119.9) > darifenacin (283.3) > pirenzepine (369.1) > p-F-HHSiD (1053.8). These potency estimates correlated most favourably (r = 0.89, P = 0.04) with the pKi estimates of these compounds at human recombinant muscarinic m2 receptors. This is consistent with a major contribution of M2 receptors in the generation of volume-induced bladder contractions, although the modest potency of darifenacin does not exclude a role of M3 receptors. Pretreatment with propranolol (1 mg kg-1, i.v.) increased the ID35%inh of methoctramine significantly from 95.9 to 404.5 nmol kg-1 but had no significant effects on the inhibitory responses to darifenacin. These data suggest an obligatory role of beta-adrenoceptors in M2 receptor-mediated bladder contractions in vivo. 5. The findings of the present study suggest that both M2 and M3 receptors can cause contraction of the rat bladder in vitro and may also mediate reflex bladder contractions in vivo. It is proposed that muscarinic M3 receptor activation primarily causes direct contraction of the detrusor whereas M2 receptor activation can contract the bladder indirectly by reversing sympathetically (i.e. beta-adrenoceptor)-mediated relaxation. This dual mechanism may allow the parasympathetic nervous system, which is activated during voiding, to cause more efficient and complete emptying of the bladder.

Background: Increased blood cholesterol, specifically high low-density lipoprotein cholesterol, increases risk for coronary heart disease (CHD). Persons with a positive family history of premature CHD also are at markedly increased risk., Objective: To examine the prevalence of hypercholesterolemia based on the second report of the National Cholesterol Educational Program Adult Treatment Panel (ATP II) guidelines in the asymptomatic healthy siblings of people with premature CHD., Methods: A total of 668 asymptomatic healthy siblings (354 men and 314 women) underwent screening for risk factors for CHD. Siblings were categorized into treatment categories for primary prevention defined by ATP II. The percentage who were candidates for intervention were compared with the published national estimates for those without CHD from the third National Health and Nutrition Examination Survey (NHANES III)., Results: Based on ATP II guidelines, 65% of the asymptomatic adult siblings required fasting lipoprotein analysis compared with 33% of adults without CHD in the national reference population. Of the siblings who met the criteria for fasting lipoprotein analysis, most (56%) were candidates for dietary therapy, more than twice the proportion of adults from NHANES III. The percentage of the siblings who qualified for drug intervention and dietary therapy was 3 times greater than the national sample, 33% vs 11%, respectively. Assuming a 10% hypothetical reduction in low-density lipoprotein cholesterol levels as the result of dietary modification, the proportion of the sibling sample who were possible candidates for drug therapy was 20%, still 4 times that predicted for the national sample., Conclusions: These results underscore the need for aggressive detection and treatment of hypercholesterolemia in this easily identifiable high-risk population of siblings of people with premature CHD.

Background: Exercise testing, even when combined with radionuclide perfusion imaging, does not accurately predict future clinical coronary heart disease (CHD) in low-risk asymptomatic populations. We hypothesized that these tests would perform better in a higher-risk population with a high prevalence of occult CHD. Siblings of persons with premature CHD represent such a group in whom it would be advantageous to identify affected individuals before the occurrence of clinically manifest CHD., Methods and Results: Exercise thallium scintigraphy was performed in 264 asymptomatic individuals less than 60 years of age who had a sibling with documented CHD before age 60. Despite an average age of only 46 years at the time of screening, 19 of 264 siblings developed clinical CHD (sudden death in 1, myocardial infarction in 10, coronary revascularization in 8) over a mean of 6.2 years (range, 1 to 9 years) of follow-up. Abnormal thallium scans were observed in 29% of men and 9% of women, while abnormal exercise ECGs occurred in 12% and 5% respectively. Of men >/= 45 years of age, 45% had an abnormal exercise ECG, thallium scan, or both. In contrast, only 3% of women < 45 years of age had an abnormal test result. Although abnormal exercise ECGs and thallium scans were both predictive of future clinical CHD, the thallium scan was associated with a higher relative risk. After adjustment for age, sex, and exercise ECG results, the relative risk of developing clinical CHD was 4.7 for an abnormal scan. Siblings with a concordant abnormal exercise ECG and thallium scan had a relative risk of 14.5. These siblings were all men > 45 years of age at the time of screening and had a strikingly high incidence of CHD (6 of 12, 50%)., Conclusions: Exercise thallium scintigraphy appears to be useful in the risk assessment of asymptomatic siblings of patients with premature CHD, particularly in male siblings who are 45 years of age or older.

The physiological role of neuropeptide Y (NPY), peptide YY (PYY) and their receptors (Y1 and Y2) has been difficult to elucidate mainly due to the lack of selective and high-affinity antagonists. Recently, Burroughs Wellcome disclosed a series of cyclic peptides, including the compound 1229U91, which were reported to be selective NPY receptor antagonists (PCT Publication No. WO 94/00486). The objective of this study was to evaluate the pharmacological properties of 1229U91. In radioligand binding studies, 1229U91 displaced specifically bound [125I]PYY from SK-N-MC cells (Y1 receptors) and SK-N-BE(2) cells (Y2 receptors) yielding pKi +/- S.E.M. estimates of 10.9 +/- 0.2 and 7.9 +/- 0.2, respectively. In the isolated perfused kidney of rat (Y1 receptor assay), NPY (10-1000 ng, bolus injection) evoked concentration-dependent increases in perfusion pressure (EC50 = 54.5 ng). In this assay, 1229U91 (1, 10 and 100 nM) produced concentration-dependent dextral displacement of the concentration-effect curve to NPY. The antagonism was surmountable at 1 nM 1229U91 (apparent pA2 estimate +/- S.E.M. = 9.3 +/- 0.4). At concentrations of 10 and 100 nM, 1229U91 produced significant depression of the maximum response to NPY (36 and 67%, respectively). In the vas deferens of rat (Y2 receptor assay), 1229U91 (3 microM) had no effect on NPY-induced inhibition of electrically evoked twitch response. In pithed rats, 1229U91 (0.3, 1 and 3 micrograms/kg/min i.v.) produced dose-dependent dextral displacement of the pressor dose-response curve to NPY yielding dose-ratio estimates of 2.4, 25.4 and 57.5, respectively. 1229U91 (3 micrograms/kg/min i.v.) had no effect on the pressor responses to norepinephrine or angiotensin II.(ABSTRACT TRUNCATED AT 250 WORDS)

Purpose: To determine the effect of a self-selected meal on concentrations of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in a screening setting and to determine the effect of using nonfasting values to classify individuals according to National Cholesterol Education Program guidelines., Subjects and Methods: Study subjects were 115 employees who had previously participated in worksite total cholesterol screening, selected by stratified random sampling for sex and total cholesterol levels. Total cholesterol, triglycerides, HDL-C, and estimated LDL-C were determined before subjects ate a self-selected breakfast and 3 and 5 hours after eating it., Results: LDL-C values determined 3 and 5 hours following breakfast were approximately 7% and 2.5% lower, respectively, than fasting values. Use of 3-hour and 5-hour LDL-C determinations to classify individuals with elevated fasting levels (> or = 3.36 mmol/L) resulted in false-negative rates of 20% and 14%, respectively. Three- and 5-hour HDL-C values were approximately 4% and 1.5% lower, respectively, than fasting levels. Use of 3-hour HDL-C values to classify individuals with low fasting levels (< 0.91 mmol/L) resulted in no false-negatives, whereas 1 of 7 individuals with low fasting HDL-C was misclassified when 5-hour values were used., Conclusions: These results support the 1993 National Cholesterol Education Program guidelines that LDL-C levels should be determined only in fasting persons, and that nonfasting HDL-C values may be acceptable for screening purposes.

It is well documented that certain substituted benzamides, such as cisapride, and benzimidazolones, such as BIMU 8, enhance gastric emptying in rats. As these compounds possess 5-HT3 antagonistic and 5-HT4 agonistic properties, the precise mechanisms (5-HT3 or 5-HT4) underlying their gastroprokinetic effects is still unclear. In the present study, we used SC 49518 (a benzamide and selective 5-HT4 receptor agonist) and two selective 5-HT4 receptor antagonists (RS 23597-190 and SB 204070) to elucidate the role of 5-HT4 receptors in gastroprokinesis. SC 49518 (1-316 micrograms/kg; ip) produced significant and dose-dependent stimulation of gastric emptying in rats (ED50 = 2.3 micrograms/kg; ip). SC 49518 also produced dose-dependent inhibition of bradycardia induced by 2-methyl 5-HT (von Bezold-Jarisch reflex) but with a 156 fold lower potency (ID50 = 0.36 mg/kg; ip). The gastroprokinetic effects of SC 49518 (3-316 micrograms/kg; ip) were significantly antagonized by the selective 5-HT4 receptor antagonist RS 23597-190 (0.1 mg/kg/min; iv). SB 204070 (0.003-1 mg/kg; ip), another selective 5-HT4 receptor antagonist, produced dose-dependent inhibition of the gastroprokinetic effects of SC 49518 (10 micrograms/kg; ip), the inhibition attaining statistical significance at the dose of 0.1 mg/kg; ip. RS 23597-190 had no effects on gastric emptying per se whereas SB 204070 significantly increased gastric emptying by itself at 1 mg/kg; ip but not at 0.1 mg/kg; ip. These findings show, for the first time, that SC 49518, a selective 5-HT4 receptor agonist, produces potent stimulation of gastric emptying in rats via a mechanism involving activation of 5-HT4 receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

The objective of this study was to characterize the receptor(s) to 5-HT mediating 5-HTP-induced diarrhea in mice. The severity of diarrhea in mice was assessed using an arbitary scoring scale ranging from 0 (normal stools) to 3 (watery diarrhea). Administration of 5-HTP (1-30 mg/kg i.p.) produced a dose-dependent increase in diarrhea score (ED50, 1.47 mg/kg i.p.). 5-HTP (10 mg/kg i.p.)-induced diarrhea was unaffected by atropine (3 mg/kg i.p.) but was completely abolished by the aromatic L-amino acid decarboxylase inhibitor benserazide (10 mg/kg i.p.). Pretreatment (5 min before 5-HTP) with DAU 6285, a marginally selective 5-HT4 receptor antagonist, significantly inhibited 5-HTP-induced diarrhea (ID50, 0.58 mg/kg i.p.). Pretreatment (5 min before 5-HTP) with GR 113808 or SB 204070, two highly selective 5-HT4 antagonists, significantly inhibited 5-HTP-induced diarrhea with ID50 estimates of 0.31 and 0.003 mg/kg i.p., respectively. The maximal inhibition produced by DAU 6285, GR 113808 and SB 204070 was 63%, 68% and 36%, respectively. Neither GR 113808 (1 and 3 mg/kg i.p.) nor SB 204070 (0.1 and 1 mg/kg i.p.) had any effect on 16,16-dimethyl prostaglandin E2 (30 micrograms/kg i.p.)-induced diarrhea in mice. DAU 6285 significantly inhibited 16,16-dimethyl prostaglandin E2-induced diarrhea at the highest dose (3 mg/kg i.p.). Pretreatment (30 min before 5-HTP) with methysergide (0.1-3 mg/kg i.p.), metergoline (0.01-0.1 mg/kg i.p.), ketanserin (0.01-1 mg/kg i.p.), YM 060 (0.01-0.1 mg/kg i.p.) or ondansetron (0.01-3 mg/kg i.p.) had no significant effects on 5-HTP-induced diarrhea.(ABSTRACT TRUNCATED AT 250 WORDS)

Monkey CV-1 cells which had received 5 Gy 12 h before harvesting lysates from their cell cultures contained approximately three times as much DNA excision repair enzyme activity as unirradiated cells. The activity was determined in crude cell lysates by the release of intermediate mobility DNA fragments and fragments with 3'-phosphoryl ends from 5'-32P-end labelled irradiated 95 bp alpha DNA. Different 3'-termini endow the fragments with differing mobilities, signifying steps in the processing of radiation damaged DNA. Similar results were obtained when Krebs II mouse tumour cells growing in mice as ascites received 5 Gy 12 h before harvest. The enzyme activities from CV-1 cells and from Krebs II cells were partially purified as 60-70 kDa proteins on Superose 12 or Ultrogel AcA-54 columns. Divalent cations were not required for enzyme activity. A 23 nucleotide long defined duplex oligodeoxynucleotide substrate containing a single 8-oxodG residue was also very actively cleaved by the partially purified cell enzymes. 8-oxoguanine is a major product of ionizing radiation's action on DNA and was recognized by the enzymes described here. The mechanism by which radiation increased excision repair activity of cellular enzymes is not understood.

Objective: --To determine the effect of filtered-coffee consumption on plasma lipoprotein cholesterol levels in healthy men., Design: --Randomized controlled trial with an 8-week washout period followed by an 8-week intervention period during which men were randomly assigned to drink 720 mL/d of caffeinated coffee, 360 mL/d of caffeinated coffee, 720 mL/d of decaffeinated coffee, or no coffee., Setting: --Outpatient clinical research center in a university medical center., Participants: --One hundred healthy male volunteers., Outcome Measure: --Changes in plasma lipoprotein cholesterol levels during the intervention period., Results: --Men who consumed 720 mL of caffeinated coffee daily had mean increases in plasma levels of total cholesterol (0.24 mmol/L, P = .001), low-density lipoprotein cholesterol (0.17 mmol/L, P = .04), and high-density lipoprotein cholesterol (0.08 mmol/L, P = .03). No significant changes in these plasma lipoprotein levels occurred in the other groups. Compared with the group who drank no coffee the group who drank 720 mL/d of caffeinated coffee had increases in plasma levels of total cholesterol (0.25 mmol/L, P = .02), low-density lipoprotein cholesterol (0.15 mmol/L, P = .17), and high-density lipoprotein cholesterol (0.09 mmol/L, P = .12) after adjustment for changes in diet., Conclusion: --Consumption of 720 mL/d of filtered, caffeinated coffee leads to a statistically significant increase in the plasma level of total cholesterol, which appears to be due to increases of both low-density lipoprotein and high-density lipoprotein cholesterol levels.

The Ca-pump in rat intestinal basolateral membranes had been studied previously as vesicular ATP-dependent Ca-uptake. In the present studies, Ca-stimulated ATP hydrolysis (Ca-ATPase activity) was measured and found to differ from the Ca-pump in having higher activity and being insensitive to vanadate. Whereas the pump was specific for ATP, hydrolytic activity was found with ATP, GTP or ADP but not with AMP or p-nitro-phenyl-phosphate. In contrast to Ca-pump activity, Ca-ATPase activities were similar for different intestinal segments, for duodenal villus/crypt cell-fractions and for vitamin D-deficient animals. Thus, as usually measured, intestinal basolateral membrane Ca-ATPase activity is not equivalent to the Ca-pump.