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Importance: Many studies that found improved quality of life (QOL) after radiotherapy of bone metastases have small sample sizes and do not use specific questionnaires. How soon after radiotherapy one can expect an improvement in QOL is unknown., Objective: To investigate QOL at days 10 and 42 after radiotherapy with a bone metastases-specific QOL tool., Design, Setting, and Participants: In this secondary analysis of the NCIC Clinical Trials Group Symptom Control Trial SC.23, a double-blind randomized clinical trial that investigated dexamethasone for the prophylaxis of pain flare after radiotherapy, patients were accrued from 23 Canadian centers from May 30, 2011, to December 11, 2014, and were followed up for 42 days after treatment. Participants referred for radiotherapy for bone metastases were required to have a pain score at the site(s) of treatment of at least 2 (range, 0-10)., Interventions: Patients were treated with a single 8-Gy radiotherapy dose for 1 or 2 bone metastases., Main Outcomes and Measures: Patients reported their worst pain score and analgesic intake at baseline and days 10 and 42 after treatment. Pain response was assessed with International Bone Metastases Consensus Endpoint Definitions. Self-reported QOL was completed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Bone Metastases Module (QLQ-BM22) and the European Organisation for Research and Treatment of Cancer Quality of Life Core 15 Palliative (QLQ-C15-PAL) at the same time points., Results: A total of 298 patients were accrued (median age, 68.8 [range, 32-94] years at day 10 and 68.0 [range, 34-90] years at day 42). A total of 122 patients (40.9%) responded to radiotherapy at day 10 and 116 patients (38.9%) at day 42. At day 10, compared with nonresponders, patients with a pain response had a greater reduction in pain (mean reduction, 17.0 vs 1.8; P = .002) and pain characteristics (mean reduction, 12.8 vs 1.1; P = .002), as well as greater improvements in functional interference (mean increase, 11.6 vs 3.6; P = .01) and psychosocial aspects (mean increase, 1.2 points in responders vs mean decrease of 2.2 points in nonresponders, P = .04). Comparing changes in QOL from baseline to day 42, responders had significantly greater improvements in the physical (mean increase, 6.2 vs -9.0; P < .001), emotional (mean increase, 12.3 vs -5.5; P < .001), and global domains (mean increase, 10.3 vs -4.5; P < .001) of the QLQ-C15-PAL compared with nonresponders., Conclusions and Relevance: Forty percent of patients experienced pain reduction and better QOL at day 10 after radiotherapy with further improvements in QOL at day 42 in responders. A single 8-Gy radiotherapy dose for bone metastases should be offered to all patients, even those with poor survival., Trial Registration: clinicaltrials.gov Identifier: NCT01248585.

Purpose: Previous studies have determined optimal cut points (CPs) for the classification of pain severity as mild, moderate, or severe using only the Brief Pain Inventory (BPI) or the BPI in conjunction with a quality of life (QOL) tool. The purpose of our study was to determine the optimal CPs based on correlation with only QOL outcomes., Methods: We conducted an analysis of 298 patients treated with radiation therapy for painful bone metastases on a phase III randomized trial. Prior to treatment, patients provided their worst pain score on a scale of 0 (no pain) to 10 (worst possible pain), as well as completed the European Organization of Cancer Research and Treatment (EORTC) QOL Questionnaire Bone Metastases module (QLQ-BM22) and the EORTC QOL Questionnaire Core-15 Palliative (QLQ-C15-PAL). Optimal CPs were determined to be those that yielded the largest F ratio for the between category effect on each subscale of the QLQ-BM22 and QLQ-C15-PAL using the multivariate analysis of variance (MANOVA)., Results: The two largest F ratios for Wilk's λ, Pillai's Trace, and Hotelling's Trace were for CPs 5,6 and 5,7. Combining both, the optimal CPs to differentiate between mild, moderate, and severe pain were 5 and 7. Pain scores of 1-5, 6, and 7-10 were classified as mild, moderate, and severe, respectively. Patients with severe pain experienced greater functional interference and poorer QOL when compared to those with mild pain., Conclusion: Our results suggest that, based on the impact of pain on QOL measures, pain scores should be classified as follows: 1-5 as mild pain, 6 as moderate pain, and 7-10 as severe pain. Optimal CPs vary depending on the type of outcome measurement used.

Advances in genome assembly and phasing provide an opportunity to investigate the diploid architecture of the human genome and reveal the full range of structural variation across population groups. Here we report the de novo assembly and haplotype phasing of the Korean individual AK1 (ref. 1) using single-molecule real-time sequencing, next-generation mapping, microfluidics-based linked reads, and bacterial artificial chromosome (BAC) sequencing approaches. Single-molecule sequencing coupled with next-generation mapping generated a highly contiguous assembly, with a contig N50 size of 17.9 Mb and a scaffold N50 size of 44.8 Mb, resolving 8 chromosomal arms into single scaffolds. The de novo assembly, along with local assemblies and spanning long reads, closes 105 and extends into 72 out of 190 euchromatic gaps in the reference genome, adding 1.03 Mb of previously intractable sequence. High concordance between the assembly and paired-end sequences from 62,758 BAC clones provides strong support for the robustness of the assembly. We identify 18,210 structural variants by direct comparison of the assembly with the human reference, identifying thousands of breakpoints that, to our knowledge, have not been reported before. Many of the insertions are reflected in the transcriptome and are shared across the Asian population. We performed haplotype phasing of the assembly with short reads, long reads and linked reads from whole-genome sequencing and with short reads from 31,719 BAC clones, thereby achieving phased blocks with an N50 size of 11.6 Mb. Haplotigs assembled from single-molecule real-time reads assigned to haplotypes on phased blocks covered 89% of genes. The haplotigs accurately characterized the hypervariable major histocompatability complex region as well as demonstrating allele configuration in clinically relevant genes such as CYP2D6. This work presents the most contiguous diploid human genome assembly so far, with extensive investigation of unreported and Asian-specific structural variants, and high-quality haplotyping of clinically relevant alleles for precision medicine.

Purpose: Validated tools for evaluating quality of life (QOL) in patients with bone metastases include the EORTC QLQ-BM22 and QLQ-C15-PAL modules. A statistically significant difference in metric scores may not be clinically significant. To aid in their interpretation, we performed analyses to determine the minimal clinically important differences (MCID) for these QOL instruments., Methods: Both anchor-based and distribution-based methods were used to determine the MCID among patients with bone metastases enrolled in a randomized phase III trial. For the anchor-based approach, overall QOL as measured by the QLQ-C15-PAL module was used as the anchor and only the subscales with moderate or better correlation were used for subsequent MCID analysis. In the anchor-based approach, patients were classified as improved, stable or deteriorated by the change in the overall QOL score from baseline to follow-up after 42 days. The MCID and confidence interval was then calculated for all subscales. In the distribution-based approach, the MCID was expressed as a proportion of the standard deviation and standard error measurement from the subscale score distribution., Results: A total of 204 patients completed the questionnaires at baseline and follow-up. Only the dyspnea and insomnia subscales did not have at least moderate correlation with the overall QOL anchor. Using the anchor-based approach, 10/11 subscales had an MCID score significantly different than 0 for improvement and 3/11 subscales had a significant MCID score for deterioration. The magnitude of MCID scores was higher for improvement in comparison with deterioration. For improvement, the anchor-based approach showed good agreement with the distribution-based approach when using 0.5 SD as the MCID. However, there was greater lack of agreement between these approaches for deterioration., Conclusion: We present the MCID scores for the EORTC QLQ-BM22 and QLQ-C15-PAL QOL instruments. The results of this study can guide clinicians in the interpretation of these instruments., Clinical Trials Registry: NCT01248585.

Purpose: Quality of life (QOL) can be compromised in patients with bone metastases, and validated QOL instruments are required to accurately measure QOL outcomes in this population. This study investigated the validity, reliability and responsiveness of the EORTC QLQ-BM22 module with the EORTC QLQ-C15-PAL instrument in bone metastases., Methods: The studied patients underwent palliative radiotherapy to bone metastases in the randomized NCIC CTG SC 23 trial. Multi-trait scaling analysis was performed to determine convergent and divergent validity among scales. Pearson coefficients were calculated to determine the correlation between items of the two instruments. The clinical validity and responsiveness of the QLQ-BM22 was tested by known group comparisons of different performance status and response to radiotherapy., Results: 204 patients completed both questionnaires at baseline and 42day follow-up. On multi-trait scaling analysis, there was mixed evidence of construct validity (explained by the questionnaire format and population characteristics). There was little correlation between most QLQ-BM22 and QLQ-C15-PAL items (except for conceptually related scales) validating their complementary nature. There were statistically significant differences in all QLQ-BM22 scale scores in groups with KPS<80 vs. KPS⩾80 and three out of four QLQ-BM22 scale scores in "responders" vs. "non-responders" to radiotherapy. In patients who responded to radiotherapy, there were statistically significant differences in all QLQ-BM22 scale scores between baseline and follow-up., Conclusion: This study further validates the use of the QLQ-BM22 as a robust and sensitive instrument to assess QOL in patients with bone metastases treated with palliative radiotherapy., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Pain flare occurs after palliative radiotherapy, and dexamethasone has shown potential for prevention of such flare. We aimed to compare the efficacy of dexamethasone with that of placebo in terms of reduction of incidence of pain flare., Methods: In this double-blind, randomised, placebo-controlled phase 3 trial, patients from 23 Canadian centres were randomly allocated (1:1) with a web-based system and minimisation algorithm to receive either two 4 mg dexamethasone tablets or two placebo tablets taken orally at least 1 h before the start of radiation treatment (a single 8 Gy dose to bone metastases; day 0) and then every day for 4 days after radiotherapy (days 1-4). Patients were eligible if they had a non-haematological malignancy and bone metastasis (or metastases) corresponding to the clinically painful area or areas. Patients reported their worst pain scores and opioid analgesic intake before treatment and daily for 10 days after radiation treatment. They completed the European Organisation for Research and Treatment of Cancer (EORTC) quality of life QLQ-C15-PAL, the bone metastases module (EORTC QLQ-BM22), and the Dexamethasone Symptom Questionnaire at baseline, and at days 10 and 42 after radiation treatment. Pain flare was defined as at least a two-point increase on a scale of 0-10 in the worst pain score with no decrease in analgesic intake, or a 25% or greater increase in analgesic intake with no decrease in the worst pain score from days 0-10, followed by a return to baseline levels or below. Primary analysis of incidence of pain flare was by intention-to-treat (patients with missing primary data were classified as having pain flare). This study is registered with ClinicalTrials.gov, number NCT01248585, and is completed., Findings: Between May 30, 2011, and Dec 11, 2014, 298 patients were enrolled. 39 (26%) of 148 patients randomly allocated to the dexamethasone group and 53 (35%) of 150 patients in the placebo group had a pain flare (difference 8·9%, lower 95% confidence bound 0·0, one-sided p=0·05). Two grade 3 and one grade 4 biochemical hyperglycaemic events occurred in the dexamethasone group (without known clinical effects) compared with none in the placebo group. The most common adverse events were bone pain (61 [41%] of 147 vs 68 [48%] of 143), fatigue (58 [39%] of 147 vs 49 [34%] of 143), constipation (47 [32%] of 147 vs 37 [26%] of 143), and nausea (34 [23%] of 147 vs 34 [24%] of 143), most of which were mild grade 1 or 2., Interpretation: Dexamethasone reduces radiation-induced pain flare in the treatment of painful bone metastases., Funding: The NCIC CTG's programmatic grant from the Canadian Cancer Society Research Institute., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

RpBphP2 and RpBphP3, two tandem bacteriophytochromes from the photosynthetic bacterium Rhodopseudomonas palustris, share high sequence identity but exhibit distinct photoconversion behavior. Unlike the canonical RpBphP2, RpBphP3 photoconverts to an unusual near-red-absorbing (Pnr) state; both are required for synthesis of light-harvesting complexes under low-light conditions. Here we report the crystal structures of the photosensory core modules of RpBphP2 and RpBphP3. Despite different quaternary structures, RpBphP2 and RpBphP3 adopt nearly identical tertiary structures. The RpBphP3 structure reveals tongue-and-groove interactions at the interface between the GAF and PHY domains. A single mutation in the PRxSF motif at the GAF-PHY interface abolishes light-induced formation of the Pnr state in RpBphP3, possibly due to altered structural rigidity of the chromophore-binding pocket. Structural comparisons suggest that long-range signaling involves structural rearrangement of the helical spine at the dimer interface. These structures, together with mutational studies, provide insights into photoconversion and the long-range signaling mechanism in phytochromes., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Rats fed gestational diets high in multivitamin or folate produce offspring of altered phenotypes. We hypothesized that female rat offspring born to dams fed a gestational diet high in folic acid (HFol) have compromised bone health and that feeding the offspring the same HFol diet attenuates these effects. Pregnant rats were fed diets with either recommended folic acid (RFol) or 10-fold higher folic acid (HFol) amounts. Female offspring were weaned to either the RFol or HFol diet for 17 weeks. HFol maternal diet resulted in lower offspring body weights (6%, P = 0.03) and, after adjusting for body weight and femoral length, smaller femoral area (2%, P = 0.03), compared to control diet. After adjustments, HFol pup diet resulted in lower mineral content (7%, P = 0.01) and density (4%, P = 0.002) of lumbar vertebra 4 without differences in strength. An interaction between folate content of the dam and pup diets revealed that a mismatch resulted in lower femoral peak load strength (P = 0.01) and stiffness (P = 0.002). However, the match in folate content failed to prevent lower weight gain. In conclusion, HFol diets fed to rat dams and their offspring affect area and strength of femurs and mineral quantity but not strength of lumbar vertebrae in the offspring.

The study aims to describe overall gestational weight gain among Canadian women and to assess demographic, socio-economic, maternal, and pregnancy-related characteristics of gestational weight gain including uncovering the predictors above or below the range recommended by Health Canada. This study proceeds as a secondary data analysis of the Maternity Experiences Survey targeting women aged ≥15 years who had singleton live births in the Canadian provinces and territories in 2005/2006. The outcome variable considered was gestational weight gain within and outside the recommended guidelines. Various factors including demographic, socio-economic, maternal, and pregnancy-related characteristics were considered using multivariate statistical techniques. Bootstrapping was performed to account for the complex sampling design. One-third of women gained within the recommended guideline (32.6%), 18.7% gained below, and 48.7% gained above the recommended guideline. More than half of overweight (67.6%) or obese women (60.0%) gained above the guideline, and women with lower socio-economic status were more likely to gain above the recommended range. Conversely, being an immigrant, multiparous, and having health problems during pregnancy were associated with less weight gain during pregnancy as well as higher odds of gaining insufficient weight to meet the minimal weight gain guideline. In Canada, almost half of the women gain above the recommended guideline for weight gain in pregnancy. The findings may be useful to design interventions that target those at risk of gaining outside of the recommended guidelines and to reduce outcomes associated with inadequate or excessive gestational weight gain.

Light is a fundamental signal that regulates important physiological processes such as development and circadian rhythm in living organisms. Phytochromes form a major family of photoreceptors responsible for red light perception in plants, fungi and bacteria. They undergo reversible photoconversion between red-absorbing (Pr) and far-red-absorbing (Pfr) states, thereby ultimately converting a light signal into a distinct biological signal that mediates subsequent cellular responses. Several structures of microbial phytochromes have been determined in their dark-adapted Pr or Pfr states. However, the structural nature of initial photochemical events has not been characterized by crystallography. Here we report the crystal structures of three intermediates in the photoreaction of Pseudomonas aeruginosa bacteriophytochrome (PaBphP). We used cryotrapping crystallography to capture intermediates, and followed structural changes by scanning the temperature at which the photoreaction proceeded. Light-induced conformational changes in PaBphP originate in ring D of the biliverdin (BV) chromophore, and E-to-Z isomerization about the C(15) = C(16) double bond between rings C and D is the initial photochemical event. As the chromophore relaxes, the twist of the C(15) methine bridge about its two dihedral angles is reversed. Structural changes extend further to rings B and A, and to the surrounding protein regions. These data indicate that absorption of a photon by the Pfr state of PaBphP converts a light signal into a structural signal via twisting and untwisting of the methine bridges in the linear tetrapyrrole within the confined protein cavity., (© 2011 Macmillan Publishers Limited. All rights reserved)

This paper presents 35 years of history of operative vaginal delivery at the Port Moresby General Hospital (PMGH). From the early 1970s when Dr. G.C. Bird was appointed as Head of Obstetrics at PMGH, vacuum extraction has been the preferred method of assisted vaginal delivery. In the early 1970s, Dr Bird began to experiment with more effective configurations of the then standard metal Malmstrom vacuum extraction cup: the Bird anterior cup was introduced in 1973 and the posterior cup in 1974. These modifications to the vacuum extractor cup allowed for more effective placement of the cup on the flexion point on the fetal head thereby facilitating more successful vacuum-assisted delivery. Between 1977 and 2010 there were a total of 11,458 vacuum extractions (average rate 3.9%) performed, with an average failure rate of 2.5%. During the same period there were 565 vaginal forceps deliveries (rate 0.2%), 11,550 caesarean sections (rate 3.9%) and 182 symphysiotomies (all for failed vacuum extraction procedures) performed. Over the period trends that are noted include a slowly rising caesarean section rate from 2% in the 1970s to nearly 5% in the current decade. Over the same period the assisted vaginal delivery rate has dropped from 10-15% in the 1970s to 3-4% since 2000. The combined fresh stillbirth and early neonatal mortality rate for infants > or = 1.5 kg and > or = 2.5 kg for the period was 11.3/1000 and 9.5/1000 respectively, and compares to a combined fresh stillbirth and early neonatal mortality rate of 8.7/1000 for assisted vaginal delivery.

Global asthma control levels are suboptimal. The influence of regular exercise on asthma control is unclear. We assessed the effects of a 12-week supervised exercise intervention followed by 12 weeks of self-administered exercise on adults with partially controlled asthma (n = 21) and matched controls (n = 15). Assessments were conducted at baseline and week 12 for both the exercise and control group, and again at week 24 for the exercise group. There was a significant treatment effect on asthma control in the exercise group, as measured by the Asthma Control Questionnaire (ACQ), from baseline to week 12, compared with the control group. A clinically significant improvement (0.5 increase in ACQ score) was observed for asthma quality of life and ACQ in the exercise group from baseline to week 12. There was a significant improvement in aerobic fitness from baseline to week 24 in the exercise group. In conclusion, a 12-week supervised exercise intervention led to improvements in asthma control and quality of life in partially controlled asthmatics motivated to exercise. These improvements were maintained, while aerobic fitness and perceived asthma control significantly improved over an additional 12 weeks of self-administered exercise. These findings indicate that a structured exercise intervention can improve asthma control.

Phytochromes are red-light photoreceptors that regulate light responses in plants, fungi, and bacteria by means of reversible photoconversion between red (Pr) and far-red (Pfr) light-absorbing states. Here, we report the crystal structure of the Q188L mutant of Pseudomonas aeruginosa bacteriophytochrome (PaBphP) photosensory core module, which exhibits altered photoconversion behavior and different crystal packing from wild type. We observe two distinct chromophore conformations in the Q188L crystal structure that we identify with the Pfr and Pr states. The Pr/Pfr compositions, varying from crystal to crystal, seem to correlate with light conditions under which the Q188L crystals are cryoprotected. We also compare all known Pr and Pfr structures. Using site-directed mutagenesis, we identify residues that are involved in stabilizing the 15Ea (Pfr) and 15Za (Pr) configurations of the biliverdin chromophore. Specifically, Ser-261 appears to be essential to form a stable Pr state in PaBphP, possibly by means of its interaction with the propionate group of ring C. We propose a "flip-and-rotate" model that summarizes the major conformational differences between the Pr and Pfr states of the chromophore and its binding pocket.

Phytochromes are red-light photoreceptors that regulate light responses in plants, fungi, and bacteria via reversible photoconversion between red (Pr) and far-red (Pfr) light-absorbing states. Here we report the crystal structure at 2.9 A resolution of a bacteriophytochrome from Pseudomonas aeruginosa with an intact, fully photoactive photosensory core domain in its dark-adapted Pfr state. This structure reveals how unusual interdomain interactions, including a knot and an "arm" structure near the chromophore site, bring together the PAS (Per-ARNT-Sim), GAF (cGMP phosphodiesterase/adenyl cyclase/FhlA), and PHY (phytochrome) domains to achieve Pr/Pfr photoconversion. The PAS, GAF, and PHY domains have topologic elements in common and may have a single evolutionary origin. We identify key interactions that stabilize the chromophore in the Pfr state and provide structural and mutational evidence to support the essential role of the PHY domain in efficient Pr/Pfr photoconversion. We also identify a pair of conserved residues that may undergo concerted conformational changes during photoconversion. Modeling of the full-length bacteriophytochrome structure, including its output histidine kinase domain, suggests how local structural changes originating in the photosensory domain modulate interactions between long, cross-domain signaling helices at the dimer interface and are transmitted to the spatially distant effector domain, thereby regulating its histidine kinase activity.

A general preparation method of the all-(E)-polyprenols 12 has been developed from readily available geranyl sulfone by the chain-extension process utilizing the C5 unit 5 and the chain-termination process utilizing the C5 unit 10 together with the chemoselective reductive desulfonylation. The polyprenols 12 were converted to compounds 3 containing two consecutive prenyl sulfone moieties at the tail end, which underwent the controlled electrophilic cyclization only at the carbon-carbon double bonds that were remote from the flat and rigid benzenesulfonyl groups.

Bacteriophytochromes RpBphP2 and RpBphP3 from the photosynthetic bacterium Rhodopseudomonas palustris work in tandem to modulate synthesis of the light-harvesting complex LH4 in response to light. Although RpBphP2 and RpBphP3 share the same domain structure with 52% sequence identity, they demonstrate distinct photoconversion behaviors. RpBphP2 exhibits the "classical" phytochrome behavior of reversible photoconversion between red (Pr) and far-red (Pfr) light-absorbing states, whereas RpBphP3 exhibits novel photoconversion between Pr and a near-red (Pnr) light-absorbing states. We have determined the crystal structure at 2.2-A resolution of the chromophore binding domains of RpBphP3, covalently bound with chromophore biliverdin IXalpha. By combining structural and sequence analyses with site-directed mutagenesis, we identify key residues that directly modulate the photochemical properties of RpBphP3 and RpBphP2. Remarkably, we identify a region spanning residues 207-212 in RpBphP3, in which a single mutation, L207Y, causes this unusual bacteriophytochrome to revert to the classical phenotype that undergoes reversible photoconversion between the Pr and Pfr states. The reverse mutation, Y193L, in the corresponding region in RpBphP2 significantly diminishes the formation of the Pfr state. We propose that residues 207-212 and the spatially adjacent conserved residues, Asp-216 and Tyr-272, interact with the chromophore and form part of the interface between the chromophore binding domains and the PHY domain that modulates photoconversion.

Structure-activity studies were performed on the alpha(1A)-adrenoceptor (AR) selective agonist N-[5-(1H-imidazol-4-yl)-5,6,7,8-tetrahydro-1-naphthalenyl]methanesulfonamide (4). Compounds were evaluated for binding activity at the alpha(1A), alpha(1b), alpha(1d), alpha(2a), and alpha(2B) subtypes. Functional activity in tissues containing the alpha(1A) (rabbit urethra), alpha(1B) (rat spleen), alpha(1D) (rat aorta), and alpha(2A) (rat prostatic vas deferens) was also evaluated. A dog in vivo model simultaneously measuring intraurethral pressure (IUP) and mean arterial pressure (MAP) was used to assess the uroselectivity of the compounds. Many of the compounds that were highly selective in vitro for the alpha(1A)-AR subtype were also more uroselective in vivo for increasing IUP over MAP than the nonselective alpha(1)-agonists phenylpropanolamine (PPA) (1) and ST-1059 (2, the active metabolite of midodrine), supporting the hypothesis that greater alpha(1A) selectivity would reduce cardiovascular side effects. However, the data also support a prominent role of the alpha(1A)-AR subtype in the control of MAP.

Glucocorticoids are potent anti-inflammatory and immunosuppressant agents. However, they also produce serious side effects that limit their usage. It has been proposed that anti-inflammatory properties of glucocorticoids are caused mostly by repression of activator protein 1- and nuclear factor kappabeta-stimulated synthesis of inflammatory mediators, whereas most of their adverse effects are associated with trans-activation of genes involved with metabolic processes. Our laboratories have sought to discover novel glucocorticoid receptor (GR) ligands that have high repression but low trans-activation activities. We describe here cellular properties of 2,5-dihydro-9-hydroxy-10-methoxy-2,2,4-trimethyl-5-(1-methylcyclohexen-3-y1)-1H-[1]benzopyrano[3,4-f]quinoline (A276575) and its four enantiomers. Similar to dexamethasone, A276575 exhibited high affinity for GR and potently repressed interleukin (IL) 1beta-stimulated IL-6 production in human skin fibroblasts, prostaglandin (PG) E(2) production in A549 human lung epithelial cells, and concanavalin A-induced monocyte proliferation. In contrast to dexamethasone, A276575 caused smaller induction of aromatase activity in human skin fibroblasts and antagonized dexamethasone-induced activation of an mouse mammary tumor virus-glucocorticoid-response element (GRE) reporter gene construct. Among the four enantiomers of A276575, the two (-)-enantiomers showed 10- to 30-fold higher affinities for GR than their respective (+)-enantiomers. Both (-)-Syn and (-)-Anti enantiomers of A276575 were potent inhibitors of IL-1beta-stimulated PGE2 production in A549 lung epithelial cells; unexpectedly, however, only the (-)-Anti enantiomer inhibited regulated on T-cell activation, normal T-cell expressed and secreted (RANTES) production in A549 cells. In summary, A276575 is a novel, nonsteroidal GR ligand that possesses high repression activities against inflammatory mediator production but has lower GRE trans-activation activities than traditional steroids. Differential repression of RANTES and PGE2 production in a cell by the two (-)-enantiomers of A276575 illustrates the complexity of repression by GR.

Calcium and aluminum phosphate binders are used to treat hyperphosphatemia which is responsible for the development of osteodystrophy commonly seen in patients with end-stage renal disease. The purpose of this study was to determine the phosphate binding capacities of several frequently used calcium and aluminum formulations. The effect of formulation types on phosphate binding was evaluated. Calcium and aluminum phosphate binders were administered to six healthy volunteers after phosphate load on separate study days. Total urine outflow was collected afterwards to determine the amount of phosphate recovered, which indicates the ability of the phosphate binder to reduce gastrointestinal phosphate absorption. The amounts of urinary phosphate recovered were different after administration of the phosphate binders. Calcium acetate resulted in the least amount of phosphate excreted. Calcium carbonate suspension, when compared with the tablet formulation, caused a smaller amount of phosphate excreted in the urine. Different phosphate binders formulations were found to have different phosphate binding capacities. Patients should therefore be closely monitored for efficacy after switching from one phosphate binder to another.

Gender has been shown to elicit differences in drug disposition and response to therapeutic agents. We measured the diuretic response to oral hydrochlorothiazide, oral and intravenous furosemide in 6 male and 6 female normal volunteers. After fasting overnight, each subject received single doses of the individual diuretics or no treatment on 4 separate days. Total urine output was collected over the next 24 hours for volume measurement and determination of sodium and potassium concentrations. There was no statistically significant difference found between male and female subjects with respect to urine flow rate, sodium, and potassium excretion rates among the treatments. However, when natriuretic response was adjusted for mg/kg of the intravenous furosemide dose received, male subjects had a higher peak sodium excretion rate than the female subjects. Results of this study reveal a gender-related difference on the natriuretic response to diuretics. Further studies are necessary to identify if this gender-related difference is caused by differences in drug metabolism, disposition, or intrinsic diuretic responsiveness at the site of action.

Diuretic drugs have been reported to alter the glomerular filtration rate and possibly the creatinine excretion by the kidneys. We evaluated the effects of single doses of diuretic drugs on creatinine clearance determination. Ten healthy volunteers were randomized to receive either oral hydrochlorothiazide, oral furosemide, intravenous furosemide, or no treatment in a cross-over fashion during four separate test days with 6-day washout periods. Urine and blood specimens were collected during 24 h after the treatments. Specimens were assayed for creatinine, and the creatinine clearance corresponding to the 4-, 6-, 12-, and 24-h urine collections were calculated. Analysis of variance did not show a statistically significant effect of the diuretic regimens on creatinine clearance over these periods. This study demonstrates that single doses of diuretic drugs do not have significant effect on creatinine clearance determination using urine collected during 4-24-h periods.

NG-Methyl-L-arginine (NMA), an inhibitor of nitric oxide synthesis by vascular endothelium, depresses cardiac function and causes systemic vasoconstriction in vivo. The mechanism of cardiac depression is unclear. Since cGMP inhibits one isoform of myocardial phosphodiesterase (PDE), we hypothesized that a decrease in cGMP might increase PDE activity and lower myocardial cAMP levels, resulting in decreased contractility. Experiments were conducted in isolated, paced, Langendorff-perfused (constant flow) rat hearts under control or isoproterenol-stimulated conditions. In non-stimulated hearts, a 15 min infusion of 30 microM NMA had no effect on cAMP content or on left ventricular dP/dt; however, myocardial cGMP content was decreased. Infusion of 0.01 microM isoproterenol caused dP/dt to increase and caused coronary resistance to fall; myocardial cAMP levels increased while cGMP remained unchanged by isoproterenol. In this stimulated condition, infusion of 30 microM NMA decreased dP/dt and myocardial cGMP and cAMP concentrations. NMA caused coronary resistance to increase to similar maximal values in isoproterenol-stimulated and non-stimulated hearts. Although coronary flow was kept constant during NMA administration, NMA depressed cardiac contractility in isoproterenol-stimulated hearts, but not in non-stimulated hearts, and the depressed contractility in isoproterenol-treated hearts was associated with a decrease in myocardial content of cGMP and cAMP. Therefore, these results are consistent with the hypothesis that NMA may decrease myocardial contractility by decreasing cGMP which leads to increased PDE activity and decreased cAMP.

Incubation of big endothelin-1 (bET-1) with protein derived from the detergent-extracted 100,000 g pellet prepared from human brain tissue resulted in the formation of endothelin-1 (ET-1) at a rate of 90 fmol mg-1 protein min-1. This formation was inhibited in a concentration-dependent manner by either phosphoramidon or EDTA, with half-maximal inhibitory concentrations of 2 and 20 microM, respectively. No conversion of big endothelin-3 (bET-3) to endothelin-3 (ET-3) was detected under the same conditions. These results show the presence in the human brain of a metalloprotease-like enzymatic activity which selectively converts bET-1 and ET-1. Together with earlier reports of mRNA for ET-1 this suggests the presence of the entire synthetic pathway for ET-1 in human brain.