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Introduction Many people with type 1 diabetes (T1DM) continue to run high HbA1c levels with an associated elevated risk of cardiovascular events and increased mortality. We describe here how adjunctive prescription of an SGLT2 inhibitor has improved the glycaemic control of several people with T1DM, where the new technology has been intensively deployed. Methods We report outcomes of six adults with T1DM who have been given dapagliflozin in East Cheshire, UK. Initiation was with education/support from the diabetes specialist nurses. All had an HbA1c of 70 mmol/mol (8.6%) or more before this was initiated. All had been monitoring glycemia with a FreeStyle Libre monitor for at least 6 months prior to this. Results The age range was 30-68 years. The mean duration of T1DM was 23.3 ± 5.5 years. All were on a basal-bolus regime. Over a 6 month period, HbA1c fell from 78.5 mmol/mol (9.3%) to 55 mmol/mol (7.2%). The greatest reduction in HbA1c was 57 mmol/mol (7.4%). Analysis of the FreeStyle Libre blood glucose records showed that the proportion of blood glucose readings on target (4-10 mmol/L) increased from 33.1 to 65.2% with the addition of dapagliflozin(P = 0.007). The proportion of blood glucose readings above target (>10 mmol/L) decreased from 68.0 to 26.4%, 6 months after initiation of dapagliflozin (P = 0.005). There was no increase in symptomatic hypoglycemia. Conclusion Dapagliflozin as adjunctive therapy to basal-bolus regime insulin in individuals with T1DM was well tolerated and improved glycemic control with no increase in hypoglycemia. We provide further evidence of the value of this intervention.

INTRODUCTION: The COVID-19 vaccination programme is under way worldwide. Anecdotal evidence is increasing that some people with Type 1 Diabetes Mellitus (T1DM) experience temporary instability of blood glucose (BG) levels post-vaccination which normally settles within 2-3 days. We report an analysis of BG profiles of 20 individuals before/after vaccination. METHODS: We examined the BG profile of 20 consecutive adults (18 years of age or more) with T1DM using the FreeStyle® Libre flash glucose monitor in the period immediately before and after COVID-19 vaccination. The primary outcome measure was percentage (%) BG readings in the designated target range 3.9-10mmmol/L as reported on the LibreView portal for 7 days prior to the vaccination (week -1) and the 7 days after the vaccination (week +1). RESULTS: There was a significant decrease in the %BG on target following the COVID-vaccination for the 7 days following vaccination (mean 45.2% ±se 4.2%) vs pre-COVID-19 vaccination (mean 52.6% ±se 4.5%). This was mirrored by an increase in the proportion of readings in other BG categories 10.1-13.9%/ ≥14%. There was no significant change in BG variability in the 7days post COVID-19 vaccination. This change in BG proportion on target in the week following vaccination was most pronounced for people taking Metformin/Dapagliflozin+basal bolus insulin (-23%) vs no oral hypoglycaemic agents (-4%), and median age

Coxiella burnetii is an obligate intracellular pathogen that causes the zoonotic disease Q fever in humans, which can occur in either an acute or a chronic form with serious complications. The bacterium has a wide host range, including unicellular organisms, invertebrates, birds and mammals, with livestock representing the most significant reservoir for human infections. Cell culture models have been used to decipher the intracellular lifestyle of C. burnetii, and several infection models, including invertebrates, rodents and non-human primates, are being used to investigate host-pathogen interactions and to identify bacterial virulence factors and vaccine candidates. However, none of the models replicate all aspects of human disease. Furthermore, it is becoming evident that C. burnetii isolates belonging to different lineages exhibit differences in their virulence in these models. Here, we compare the advantages and disadvantages of commonly used infection models and summarize currently available data for lineage-specific virulence.

Introduction: Chest radiographs form an important aid to COVID-19 diagnosis, however their utility is limited by the reviewers ability to accurately assess for its radiological features, This study seeks to assess for any difference in reporting between radiologists and clinicians. Methods: 135 admission chest radiographs of patients without a known COVID-19 diagnosis were gathered opportunistically. Radiologist reports, reviewing clinicians and clinicians with no knowledge of the patient categorised radiographs as having either “no covid signs” (category 0), “indeterminate covid signs” (cat. 1) or “classic/probable covid signs” (cat. 2). Cohen’s Kappa was used to evaluate the inter-reporter reliability between these groups. Results: Radiologists identified 69% as cat. 0, 29% as cat. 1, 5% as cat. 2. Reviewing clinicians agreed with 73% of these reports achieving a Kappa of 0.43 (95% CI 0.32 - 0.54). Consultants performed best with a kappa of 0.77 (0.56-0.98). Clinicians without knowledge of the patient agreed with 54% of reports, Kappa 0.17 (-0.16 -0.50). Conclusion: There is a significant discrepancy between radiologist and non-radiologist reporting of chest radiographs in COVID-19 supporting the use of rapid radiologist reporting of chest radiographs to aid with diagnosis. Advances in Knowledge: This is the first paper to our knowledge to assess the difference in reporting of COVID-19 between radiologists and reviewing clinicians, indicating that radiologist reporting of chest x-rays has a measurable advantage in detecting COVID-19 signs, compared to clinician reports alone.

Introduction Many people with type 1 diabetes continue to run high HbA1c levels with associated elevated risk of cardiovascular events and increased mortality. We describe here how use of the FreeStyle Libre flash monitor has improved the glycaemic control of many people with type 1 diabetes where the new technology has been intensively deployed. Methods We report the outcomes of 92 consecutive adults (18 years of age or more) with type 1 diabetes who have begun using the FreeStyle Libre flash glucose monitor in East Cheshire, UK. Initiation was with education and support from one of the diabetes specialist nurses. An HbA1c of 60 mmol/mol (7.6%) was taken as the threshold for suboptimal glycaemic control. Results The mean cohort age was 43 years for men and 39 years for women (overall range 17-83 years). In 92 consecutive users, HbA1c decreased by an average of 10.7 mmol/mol (0.98%) after 3 months, and by 16.1 mmol/mol (1.47%) after 6 months. There was also a narrowing of the distribution of HbA1c, with many fewer people running high HbA1c ≥80 mmol/mol (9.5%). After the 6-month follow-up, two 2/92 users did not wish to continue with the monitoring. Conclusion Flash glucose monitoring has great potential for the management of type 1 diabetes in the adult population and improving metabolic control/quality of life for people across the world. The technology provides significantly more data than the intermittent results obtained by traditional subcutaneous blood glucose monitoring, which may not capture intervals of extreme variability or nocturnal events.

Staphylococcus pseudintermedius is an important member of the skin microbial community in animals and can cause opportunistic infections in both pets and their owners. The high incidence of antimicrobial resistance in S. pseudintermedius highlights that this opportunistic zoonotic pathogen can cause infections which require prolonged and intensive treatment to resolve. Manuka honey has proven efficacy against many bacterial pathogens and is an accepted topical treatment for infections in both veterinary and clinical practice, and so it is a particularly appropriate antimicrobial for use with zoonotic pathogens such as S. pseudintermedius. Here, we demonstrate that not only is manuka honey highly potent against novel multidrug-resistant S. pseudintermedius isolates, it also acts synergistically with clinically relevant antibiotics. In addition, manuka honey modulates S. pseudintermedius virulence activity, even at subinhibitory concentrations. In a clinical setting, these attributes may assist in controlling infection, allowing a more rapid resolution and reducing antibiotic use., Staphylococcus pseudintermedius causes opportunistic infections in dogs. It also has significant zoonotic potential, with the emergence of multidrug resistance leading to difficulty treating both animal and human infections. Manuka honey has previously been reported to inhibit many bacterial pathogens, including methicillin-resistant Staphylococcus aureus, and is successfully utilized in both clinical and veterinary practice. Here, we evaluated the ability of manuka honey to inhibit strains of S. pseudintermedius grown alone and in combination with antibiotics, as well as its capacity to modulate virulence within multiple S. pseudintermedius isolates. All 18 of the genetically diverse S. pseudintermedius strains sequenced and tested were inhibited by ≤12% (wt/vol) medical-grade manuka honey, although tolerance to five clinically relevant antibiotics was observed. The susceptibility of the isolates to four of these antibiotics was significantly increased (P ≤ 0.05) when combined with sublethal concentrations of honey, although sensitivity to oxacillin was decreased. Virulence factor (DNase, protease, and hemolysin) activity was also significantly reduced (P ≤ 0.05) in over half of isolates when cultured with sublethal concentrations of honey (13, 9, and 10 isolates, respectively). These findings highlight the potential for manuka honey to be utilized against S. pseudintermedius infections. IMPORTANCE Staphylococcus pseudintermedius is an important member of the skin microbial community in animals and can cause opportunistic infections in both pets and their owners. The high incidence of antimicrobial resistance in S. pseudintermedius highlights that this opportunistic zoonotic pathogen can cause infections which require prolonged and intensive treatment to resolve. Manuka honey has proven efficacy against many bacterial pathogens and is an accepted topical treatment for infections in both veterinary and clinical practice, and so it is a particularly appropriate antimicrobial for use with zoonotic pathogens such as S. pseudintermedius. Here, we demonstrate that not only is manuka honey highly potent against novel multidrug-resistant S. pseudintermedius isolates, it also acts synergistically with clinically relevant antibiotics. In addition, manuka honey modulates S. pseudintermedius virulence activity, even at subinhibitory concentrations. In a clinical setting, these attributes may assist in controlling infection, allowing a more rapid resolution and reducing antibiotic use.

AIM To quantify the real-world clinical and cost impact of computed tomography (CT) coronary angiography (CTCA)-derived fractional flow reserve (FFRCT) in the National Health Service (NHS). MATERIALS AND METHODS Consecutive clinical CTCA examinations from September to December 2018 with ≥1 stenosis of ≥25% underwent FFRCT analysis. The Heart Team reviewed clinical data and CTCA findings, blinded to FFRCT values, and documented hypothetical consensus management. FFRCT results were then unblinded and hypothetical consensus management re-recorded. Diagnostic waiting times for management pathways were estimated. A per-patient cost analysis for diagnostic certainty regarding coronary artery disease (CAD) management was performed using 2014–2020 NHS tariffs for pre- and post-FFRCT pathways. RESULTS Two hundred and fifty-one CTCAs were performed during the study period. Fifty-seven percent (145/251) had no CAD or stenosis CONCLUSIONS In the real-world NHS setting, FFRCT-guided management has the potential to rationalise patient management, accelerate diagnostic pathways, and depending on the stenosis severity modelled, may be cost-effective.

The electrochemical sensing of new psychoactive substance(s) (NPSs), synthetic cathinone derivatives also termed "legal highs", are explored with the use of metallic modified screen-printed electrochemical sensors (SPES). It is found that no significant electrochemical enhancement is evident with the use of either in situ bismuth or mercury film modified SPES compared to the bare underlying electrode substrate. In fact, the direct electrochemical reduction of the cathinone derivatives mephedrone (4-methylmethcathinone; 4-MMC) and 4'-methyl-N-ethylcathinone (4-methylethcathinone; 4-MEC) is found to be possible for the first time, without heavy metal catalysis, giving rise to useful voltammetric electroanalytical signatures in model aqueous buffer solutions. This novel electroanalytical methodology is validated toward the determination of cathinone derivatives (4-MMC and 4-MEC) in three seized street samples that are independently analyzed with high-performance liquid chromatography (HPLC) wherein excellent agreement between the two analytical protocols is found. Such an approach provides a validated laboratory tool for the quantification of synthetic cathinone derivatives and holds potential for the basis of a portable analytical sensor for the determination of synthetic cathinone derivatives in seized street samples.

Hydrogels are an important class of biomaterials for cell encapsulation and delivery, providing a physical barrier or "immuno-isolation" between the host tissue and encapsulated cells. The semi-permeable gel protects the encapsulated cells from host immune cells and/or antibody recognition while allowing facile diffusion of nutrients. However, a previously un-addressed problem is that highly permissive hydrogels cannot exclude the infiltration of soluble immune-mediators, such as pro-inflammatory cytokines that are highly expressed in wounded environments in vivo. When encountered with pro-inflammatory cytokines, encapsulated cells fail to perform their desired functions. Here, we report the synthesis, characterization, and application of peptide-functionalized, cytokine-antagonizing poly(ethylene glycol) (PEG) hydrogels capable of sequestering the pro-inflammatory cytokine, tumor necrosis factor alpha (TNFalpha). Results demonstrate that the survival, function, and differentiation of encapsulated cells (e.g., rat adrenal pheochromocytoma cells--PC12s, mouse pancreatic islets, and human mesenchymal stem cells or hMSCs) are significantly hindered in un-modified PEG hydrogels under in vitro TNFalpha treatments. In contrast, cells encapsulated in TNFalpha-antagonizing hydrogels are un-affected by the infiltrated TNFalpha. This study demonstrates the importance of controlling the availability of pro-inflammatory cytokines in highly permissive hydrogels.

The degradation of polymers under ultraviolet (UV) irradiation has been a great concern for biomaterial and agricultural applications. The major objective of this research was to study the effect of UV irradiation on the representative bulk and surface properties of poly (L-lactide) (PLA) films. Two UV sources with different spectral outputs and intensities were chosen so that one of them could be used for surface modification and the other could be used for UV sterilization of the PLA films. The results established that the molecular weight of PLA decreased significantly during irradiation from the photografting lamp under atmospheric conditions. Irradiation through a Pyrex container was shown to minimize polymer degradation during UV exposure from the photografting lamp. The PLA films UV-irradiated under the sterilization lamp for 12 h revealed a similar reduction in the molecular weight and no change in the surface hydrophilicity. However, significantly less photodegradation was observed under the sterilization lamp when the samples were held in a Pyrex container. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

Recent work has reported the first electroanalytical detection of pindolol using reduced graphene oxide (RGO) modified glassy carbon electrodes [S. Smarzewska and W. Ciesielski, Anal. Methods, 2014, 6, 5038] where it was reported that the use of RGO provided significant improvements in the electroanalytical signal in comparison to a bare (unmodified) glassy carbon electrode. We demonstrate, for the first time, that the electroanalytical quantification of pindolol is actually possible using bare (unmodified) screen-printed graphite electrodes (SPEs). This paper addresses the electroanalytical determination of pindolol utilising RGO modified SPEs. Surprisingly, it is found that bare (unmodified) SPEs provide superior electrochemical signatures over that of RGO modified SPEs. Consequently the electroanalytical sensing of pindolol is explored at bare unmodified SPEs where a linear range between 0.1 μM–10.0 μM is found to be possible whilst offering a limit of detection (3σ) corresponding to 0.097 μM. This provides a convenient yet analytically sensitive method for sensing pindolol. The optimised electroanalytical protocol using the unmodified SPEs, which requires no pre-treatment (electrode polishing) or electrode modification step (such as with the use of RGO), was then further applied to the determination of pindolol in urine samples. This work demonstrates that the use of RGO modified SPEs have no significant benefits when compared to the bare (unmodified) alternative and that the RGO free electrode surface can provide electro-analytically useful performances. Financial support for this research was supplied by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).

Nicotinic acid (NA) is commonly used to treat dyslipidemia, but it elicits an adverse effect, termed flushing, which consists of cutaneous vasodilation with associated discomfort. An animal model of NA-induced flushing has been established in mice. As in humans, NA stimulated vasodilation in a dose-dependent manner, was associated with an increase of the vasodilatory prostaglandin (PG) D 2 in plasma and could be blocked by pretreatment with aspirin. Two PGD 2 receptors have been identified: PGD 2 receptor 1 (DP1, also called DP) and PGD 2 receptor 2 (DP2, sometimes termed CRTH2). DP2 does not mediate NA-induced vasodilation; the DP2-specific agonist DK-PGD 2 (13,14-dihydro-15-keto-PGD 2 ) did not induce cutaneous vasodilation, and DP2 −/− mice had a normal vasodilatory response to NA. By contrast, BW245C, a DP1-selective agonist, induced vasodilation in mice, and MK-0524, a DP1-selective antagonist, blocked both PGD 2 - and NA-induced vasodilation. NA-induced vasodilation was also studied in DP1 +/+ , DP1 +/− , and DP1 −/− mice; although NA-induced vasodilation depended almost completely on DP1 in female mice, it depended only partially on DP1 in male mice. The residual NA-induced vasodilation in male DP −/− mice was aspirin-sensitive. Thus, in the mouse, DP1 appears to be an important component involved in NA-induced vasodilation, but other cyclooxygenase-dependent mechanisms also may be involved. A clinical study in healthy men and women demonstrated that treatment with MK-0524 reduced the symptoms of flushing and the increase in skin perfusion after the administration of NA. These studies suggest that DP1 receptor antagonism may be an effective means to suppress NA-induced flushing in humans.

Hydrogels were formed by conjugate addition of polyethylene glycol (PEG) multiacrylates and dithiothreitol (DTT) for encapsulation and sustained release of protein drugs; human growth hormone (hGH) was considered as an example. Prior to encapsulation, the hGH was precipitated either by Zn2+ ions or by linear PEG, to protect the hGH from reaction with the gel precursors during gelation. Precipitation by Zn2+ ions yielded precipitates that dissolved slowly and delayed release from even highly permeable gels, whereas linear PEG yielded rapidly dissolving precipitates. To independently protect the protein and delay its release, linear PEG precipitation was adopted, and release control via modulation of the PEG gel mesh size was sought. By varying the molecular weight of the multiarm PEG acrylates, control over gel swelling and hGH release, from a few hours to a few months, could be obtained. Protein release from the swollen and degrading PEG-based gel networks was modeled as a diffusion process with a time-dependent diffusion coefficient, calculated from swelling measurements and theoretical mesh sizes. Release following zero-order kinetics was obtained by the counter influences of decreasing protein concentration and increasing protein diffusion coefficient over time.

A statistical-co-kinetic model has been developed to predict effects of hydrolytic or enzymatic degradation on the macroscopic properties of hydrogels formed through Michael-type addition reactions. Important parameters accounted for by the theoretical calculations are bond cleavage kinetics, microstructural network characteristics such as macromer functionality and crosslinking efficiency, and detailed analysis of degradation products. Previous work indicated the validity of this modeling approach for predicting swelling behavior of hydrolytically degradable gels during early stages of degradation and the quantitative dependence of gel degradation on kinetic and structural parameters. The theoretical methodology is extended in the current work to predict release of covalently bound proteins from the network via labile bonds. Release studies of a network-bound fluoroscopic probe allow validation of model degradation parameters and indicate that macromer functionalization and network crosslinking efficiency can be appropriately tailored to achieve desired swelling profiles and protein release rates over the lifetime of the degradable gel. The effects of these network parameters on the timing of gel dissolution and the protein release that occurs during this phase of degradation are also identified, highlighting the utility of the developed model as a comprehensive tool for optimizing degradable hydrogels as matrices for drug delivery and tissue regeneration.

Here we present a comprehensive molecular mapping of virus-induced autoimmune B cell responses obtained by serological identification of antigens by recombinant expression cloning analysis. Immunoscreening of cDNA expression libraries of various organs (lung, liver, and spleen) using sera from mice infected with cytopathic (vaccinia virus [VV]) or noncytopathic (lymphocytic choriomeningitis virus [LCMV]) viruses revealed a broad specificity of the elicited autoantibody response. Interestingly, the majority of the identified autoantigens have been previously described as autoantigens in humans. We found that induction of virus-induced autoantibodies of the immunoglobulin G class largely depends on the CD40–CD40L-mediated interaction between T and B cells. Furthermore, antibody titers against a number of autoantigens were comparable to the concomitantly induced antiviral antibody response. Comparison of serum reactivity against a selected panel of autoantigens after infection with VV, LCMV, or vesicular stomatitis virus showed that the different virus infections triggered distinct autoantibody responses, suggesting that virus infections may leave specific “autoantibody fingerprints” in the infected host.

Dendritic cells (DC) are potent immunostimulatory cells facilitating antigen transport to lymphoid tissues and providing efficient stimulation of T cells. A series of experimental studies in mice demonstrated that cytotoxic T lymphocytes (CTL) can be efficiently induced by adoptive transfer of antigen-presenting DC. However, the success of DC-based immunotherapeutic treatment of human cancer, for example, is still limited because the details of the regulation and kinetics of the DC-CTL interaction are not yet completely understood. Using a combination of experimental mouse studies, mathematical modeling, and nonlinear parameter estimation, we analyzed the population dynamics of DC-induced CTL responses. The model integrates a predator-prey-type interaction of DC and CTL with the non-linear compartmental dynamics of T cells. We found that T cell receptor avidity, the half-life of DC, and the rate of CTL-mediated DC-elimination are the major control parameters for optimal DC-induced CTL responses. For induction of high avidity CTL, the number of adoptively transferred DC was of minor importance once a minimal threshold of approximately 200 cells per spleen had been reached. Taken together, our study indicates that the availability of high avidity T cells in the recipient in combination with the optimal application regimen is of prime importance for successful DC-based immunotherapy.

Rationale Prostaglandin D 2 (PGD 2 ) is released from mast cells during the allergic response. Since PGD 2 has been shown to induce nasal congestion in humans, we investigated the distribution of hematopoietic Prostaglandin D synthase (PGDS) and the two PGD 2 receptors, DP and CRTH2 in human nasal mucosa from healthy subjects and subjects suffering from polyposis, a severe form of chronic rhinosinusitis. Methods DP mRNA expression was detected by in situ hybridization while PGDS, CRTH2 and various leukocyte markers expression was revealed by immunohistochemistry. Results In the normal mucosa, PGDS was only detected in few resident mast cells while CRTH2 was undetectable. In contrast, DP receptor mRNA was detected in epithelial goblet cells, serous glands and in the vasculature. In the nasal mucosa of subjects suffering from polyposis: 1) PGDS was detected in mast cells and other large infiltrating inflammatory cells, 2) both DP mRNA and CRTH2 were detected in eosinophils and 3) CRTH2 was detected on a subset of infiltrating T-cells. Although DP mRNA could not be detected in the T-cells invading the nasal mucosa, it was found to be expressed in the T-cells present in the lymph node and the thymus from normal individuals. Conclusions This study indicates that cells capable of producing PGD 2 are present in the nasal mucosa and that both PGD 2 receptors, DP and CRTH2, might play a role in inflammatory disease of the upper airways.

It has recently been demonstrated that 2-aminoacetophenone (2-AA) is a chemical indicator in exhaled air/breath of Pseudomonas aeruginosa infection associated with progressive life threatening decline of lung function in cystic fibrosis sufferers [Scott-Thomas et al., BMC Pulm. Med., 2010, 10, 56]. Currently the detection of 2-AA involves laboratory based instrumentation such as mass spectrometry and a hand-held point-of-care type breath device would be ideal in providing real-time results within seconds to accelerate patient care decision-making processes. To this end, we demonstrate proof-of-concept that the chemical marker 2-AA, indicative of Pseudomonas aeruginosa infection, can be measured using electrochemical based sensing strategies. A range of commercially available electrode substrates are explored demonstrating for the first time that 2-AA is electrochemically active within aqueous based solutions providing an (electro)analytical signal. Glassy carbon, boron-doped diamond and platinum electrodes have been explored towards the electrochemical oxidation of 2-AA. Electrode fouling is observed requiring pre-treatment in the form of mechanical polishing between voltammetric scans and measurements. To alleviate this, screen-printed graphite electrodes are shown to be a more viable option for implementation into breath sensing devices and overcome the fouling problem since due to their low cost and disposable nature, a new electrode can be used for each measurement. The analytical utility of the platinum, screen-printed and boron-doped diamond electrodes were found to correspond to 6.85, 7.66 and 4.86 mM respectively. The challenges associated with the electrochemical sensing of 2-AA in breath that need to be overcome are discussed. This generic approach where electrochemical based technology is used to provide measurements for chemical markers in exhaled air/breath for medical diagnostics termed electrochemical breathprints (ec-breathprints), has the potential to be developed into a hand-held point-of-care breath diagnostic tool for identifying Pseudomonas aeruginosa infection in exhaled air/breath.

Recently it has been shown that chemical markers in exhaled air/breath can provide a methodology for the detection of tuberculosis infection. These markers consist of methyl phenylacetate, methyl p-anisate, methyl nicotinate and o-phenylanisole (2-methoxybiphenyl). Current approaches utilise gas chromatography-mass spectrometry (GCMS) which are useful for centralised testing of breath samples. The World Health Organization (WHO) require a portable, non-invasive diagnostic tool for the screening of tuberculosis infection. In order to meet this, we demonstrate proof-of-concept for the analytical sensing of the identified chemical markers in aqueous solutions using electrochemical based technology. We demonstrate that screen-printed electrochemical sensors can be used as the basis of a diagnostic tool for the electrochemical breathprinting of chemical markers (methyl nicotinate and 2-methoxybiphenyl) useful for the screening of tuberculosis infection. It is hoped that further development will facilitate the potential for a portable, hand-held, non-invasive breath diagnostic tool to be realised.

Background: PGD 2 is the major prostanoid released by mast cells during an allergic response. Its role in the allergic response, however, remains unclear. Objective: Because the accumulation of eosinophils is a feature of allergic reactions, we investigated the role of PGD 2 in the modulation of eosinophil function. Methods: Circulating human eosinophils were isolated and challenged with PGD 2 . The effects of PGD 2 on various eosinophil functions were then analyzed. Results: PGD 2 binds with high affinity preferentially to 2 receptors, DP and chemoattractant receptor-homologous molecule expressed on T H 2 cells (CRTH2). We show that both DP and CRTH2 are detectable on circulating eosinophils. We demonstrate that PGD 2 (1-10 nmol/L) induces a rapid change in human eosinophil morphology and an increase in chemokinesis and promotes eosinophil degranulation. These effects are induced by the CRTH2-selective agonist 13-14-dihydro-15-keto-PGD 2 (DK-PGD 2 ) but not by the DP-selective agonist BW245C. These results suggest a role for CRTH2 in the modulation of eosinophil movement and in triggering the release of cytotoxic proteins. Finally, we demonstrate that BW245C, but not DK-PGD 2 , can delay the onset of apoptosis in cultured eosinophils, presumably through interaction with DP. Conclusion: These data support the hypothesis that PGD 2 controls eosinophil functions through 2 pharmacologically distinct receptors with independent functions. Blockade of PGD 2 -mediated effects on human eosinophils may reduce the damage caused by these cells during an allergic response, but inhibition of both receptors may be required. (J Allergy Clin Immunol 2001;108:982-8.)

The prostaglandin E 2 (PGE 2 ) EP 4 subtype is one of four prostanoid receptors that use PGE 2 as the preferred ligand. We have investigated the agonist-mediated regulation of EP 4 using a multifaceted approach. Short-term (30 min) agonist challenge of recombinant EP 4 expressed in human embryonic kidney 293 cells (EP 4 -HEK293 cells) with PGE 2 (1 μM) resulted in the desensitization of intracellular cyclic AMP (cAMP) accumulation and a reduction in cell surface [ 3 H]PGE 2 specific binding sites. These events correlated with sequestration of EP 4 , as visualized by immunofluorescence confocal microscopy and phosphorylation, as shown by [ 32 P]orthophosphate labeling of the receptor. Stimulation of protein kinase A activity in EP 4 -HEK293 cells (10 μM forskolin or 1 mM 8-bromo-cAMP) did not induce EP 4 desensitization, sequestration, or phosphorylation. In contrast, stimulation of protein kinase C activity (100 nM phorbol 12-myristate 13-acetate) attenuated PGE 2 -induced adenylyl cyclase activity and increased EP 4 phosphorylation, but did not induce sequestration or a reduction in [ 3 H]PGE 2 specific binding sites. EP 4 receptors containing a third intracellular loop deletion [EP 4 (del. 215–263)] or a carboxyl-terminal tail truncation [EP 4 (del. 355)] of EP 4 were used to demonstrate that the C-terminal tail governs sequestration as well as phosphorylation of the receptor.

Prostaglandin (PG) E(2) is a potent inducer of cortical and trabecular bone formation in humans and animals. Although the bone anabolic action of PGE(2) is well documented, the cellular and molecular mechanisms that mediate this effect remain unclear. This study was undertaken to examine the effect of pharmacological inactivation of the prostanoid receptor EP(4), one of the PGE(2) receptors, on PGE(2)-induced bone formation in vivo. We first determined the ability of EP(4)A, an EP(4)-selective ligand, to act as an antagonist. PGE(2) increases intracellular cAMP and suppresses apoptosis in the RP-1 periosteal cell line. Both effects were reversed by EP(4)A, suggesting that EP(4)A acts as an EP(4) antagonist in the cells at concentrations consistent with its in vitro binding to EP(4). We then examined the effect of EP(4) on bone formation induced by PGE(2) in young rats. Five- to 6-week-old rats were treated with PGE(2) (6 mg/kg/day) in the presence or absence of EP(4)A (10 mg/kg/day) for 12 days. We found that treatment with EP(4)A suppresses the increase in trabecular bone volume induced by PGE(2). This effect is accompanied by a suppression of bone formation indices: serum osteocalcin, extent of labeled surface, and extent of trabecular number, suggesting that the reduction in bone volume is due most likely to decreased bone formation. The pharmacological evidence presented here provides strong support for the hypothesis that the bone anabolic effect of PGE(2) in rats is mediated by the EP(4) receptor.

We report the successful introduction of student report focus groups (SFGS) as an element of our School of Pharmacy quality management programme. Student focus groups feature focused discussion, problem-solving and brainstorming, which allow students at each level of the Master of Pharmacy (MPharm) degree to contribute opinion, commentary, ideas and solutions to the School of Pharmacy (the School) and, in so doing, enhance their own and their colleagues’ education. Focus group outputs are formallyreported to the MPhann Course Board and the focus group facilitator closes the reporting loop by reporting Course Board decisions back to the SFG. The group facilitatormoderates meetings, and is a member of the teaching staff who has a pre-existingprofessional rela:tion.ship with the group. The School demonstrably benefits from inputs, while the group memttem benefit by gaining transferable skills. Group members also gain the opportunity to contribute to the School quality management and assessment process. Qualitative and quantitative evaluations are included which indicate that such groups provide a valuable contribution to the quality management programme of the School. The variety of ways in which the group membersand the whole student body benefit are described.

This study demonstrates the localization of the prostaglandin (PG)D2 receptor (DP) within the mucous-secreting globlet cells of the human colon by in situ hybridization, which suggests a role for DP in mucous secretion. Selective high affinity ligands were used, therefore, to evaluate DP regulation of mucous secretion in LS174T human colonic adenocarcinoma cells. The expression of hDP in LS174T cells was confirmed at the mRNA level by reverse transcriptase-polymerase chain reaction, and at the protein level by radioligand binding assays and signal transduction (cyclic AMP accumulation) assays. PGD2 and the highly selective DP-specific agonist L-644,698 ((4-(3-(3-(3-hydroxyoctyl)-4-oxo-2-thiazolidinyl) propyl) benzoic acid) (racemate)), but not PGE2 competed for [3H]-PGD2-specific binding to LS174T cell membranes (Ki values of 0.4 nM and 7 nM, respectively). The DP-specific agonists PGD2, PGJ2, BW245C (5-(6-carboxyhexyl)-1-(3-cyclohexyl-3-hydroxypropylhydantoin)), and L-644,698 showed similar potencies in stimulating cyclic AMP accumulation (EC50 values: 45–90 nM) and demonstrated the expected rank order of potency. PGE2 also elicited cyclic AMP production in this cell line (EC50 value: 162 nM). The activation of cyclic AMP production by PGD2 and L-644,698, but not PGE2, was inhibited by the selective DP antagonist BW A868C. Thus, PGD2 and L-644,698 act through hDP in LS174T cells. PGD2, L-644,698 and PGE2 (an established mucin secretagogue) potently stimulated mucin secretion in LS174T cells in a concentration-dependent manner (EC50

Demonstrating in vivo interaction of two important biomolecules and the relevance of the interaction to a biological process have been difficult issues in biomedical research. Here, we report the use of a homology modeling approach to establish the significance of protein interactions in governing the activation of programmed cell death in Caenorhabditis elegans. A protein interaction cascade has been postulated to mediate activation of cell death in nematodes, in which the BH3-domain-containing (Bcl-2 homology region 3) protein EGL-1 binds the cell-death inhibitor CED-9 and induces release of the death-activating protein CED-4 from inhibitory CED-4/CED-9 complexes. We show here that an unusual gain-of-function mutation in ced-9 (substitution of glycine 169 to glutamate) that results in potent inhibition of most nematode cell deaths impairs the binding of EGL-1 to CED-9 and EGL-1-induced release of CED-4 from CED-4/CED-9 complexes. Based on a modeled EGL-1/CED-9 complex structure, we generated second-site compensatory mutations in EGL-1 that partially restore the binding of EGL-1 to CED-9(G169E) and EGL-1-induced release of CED-4 from CED-4/CED-9(G169E) complexes. Importantly, these mutations also significantly suppress the death-protective activity of CED-9(G169E) in vivo . These results establish that direct physical interaction between EGL-1 and CED-9 is essential for the release of CED-4 and the activation of cell death. The structure-based design of second-site suppressors via homology modeling should be widely applicable for probing important molecular interactions that are implicated in fundamental biological processes.

The degradation behavior of highly swollen, chemically cross-linked hydrogels was characterized by monitoring changes in their mass loss, degree of swelling and compressive modulus. The hydrogels were used as model systems to investigate the hydrolytic degradation process in cross-linked networks. The trends of the three measured properties differ substantially from those seen for linear degradable systems; however, they can still be predicted accurately using hydrolysis kinetics and network structure. Experimental results show that the modulus decreases exponentially with time while the volumetric swelling ratios for these gels increase exponentially. The characteristic exponential time constants for these two functions, as well as the overall degradation timescale, are influenced greatly by the network structure. Thermodynamic relationships are used to explain these trends as well as relating the observed tradeoff between the two desirable properties of mechanical strength and water content.

1 We characterized the regulation of cyclooxygenase-2 (COX-2) at the mRNA, protein and mediator level in two rat models of acute inflammation, carrageenan-induced paw oedema and mechanical hyperalgesia. 2 Carrageenan was injected in the hind paw of rat at low (paw oedema) and high doses (hyperalgesia). COX-2 and prostaglandin E2 (PGE2) levels were measured by RT-PCR and immunological assays. We also determined the distribution of COX-2 by immunohistochemistry. 3 The injection of carrageenan produced a significant and parallel induction of both COX-2 and PGE2. This induction was significantly higher in hyperalgesia than in paw oedema. This was probably due to the 9 fold higher concentration of carrageenan used to provoke hyperalgesia. 4 Immunohistochemical examination showed COX-2 immunoreactivity in the epidermis, skeletal muscle and inflammatory cells of rats experiencing hyperalgesia. In paw oedema however, only the epidermis showed positive COX-2 immunoreactivity. 5 Pretreatment with indomethacin completely abolished the induction of COX-2 in paw oedema but not in hyperalgesia. 6 These results suggest that multiple mechanisms regulate COX-2 induction especially in the more severe model. In carrageenan-induced paw oedema, prostanoid production have been linked through the expression of the COX-2 gene which suggest the presence of a positive feedback loop mechanism.

1. A human embryonic kidney cell line [HEK 293(EBNA)] stably expressing the human recombinant prostaglandin D2 (PGD2) receptor (hDP) has been characterized with respect to radioligand binding and signal transduction properties by use of prostanoids and prostanoid analogues. Radioligand binding studies included saturation analyses, the effects of nucleotide analogues, the initial rate of ligand-receptor association and equilibrium competition assays. In addition, adenosine 3':5'-cyclic monophosphate (cyclic AMP) generation in response to ligand challenge was also measured, as this is the predominant hDP signalling pathway. 2. L-644,698 ((4-(3-(3-(3-hydroxyoctyl)-4-oxo-2-thiazolidinyl) propyl) benzoic acid) (racemate)) was identified as a novel ligand having high affinity for hDP with an inhibitor constant (Ki) of 0.9 nM. This Ki value was comparable to the Ki values obtained in this study for ligands that have previously shown high affinity for DP: PGD2 (0.6 nM), ZK 110841 (0.3 nM), BW245C (0.4 nM), and BW A868C (2.3 nM). 3. L-644,698 was found to be a full agonist with an EC50 value of 0.5 nM in generating cyclic AMP following activation of hDP. L-644,698 is, therefore, comparable to those agonists with known efficacy at the DP receptor (EC50): PGD2 (0.5 nM), ZK 110841 (0.2 nM) and BW245C (0.3 nM). 4. L-644,698 displayed a high degree of selectivity for hDP when compared to the family of cloned human prostanoid receptors: EP1 (> 25,400 fold), EP2 (approximately 300 fold), EP3-III (approximately 4100 fold), EP4 (approximately 10000 fold), FP (> 25,400 fold), IP (> 25,400 fold) and TP (> 25,400 fold). L-644,698 is, therefore, one of the most selective DP agonists as yet described. 5. PGJ2 and delta12-PGJ2, two endogenous metabolites of PGD2, were also tested in this system and shown to be effective agonists with Ki and EC50 values in the nanomolar range for both compounds. In particular, PGJ2 was equipotent to known DP specific agonists with a Ki value of 0.9 nM and an EC50 value of 1.2 nM.

The structure-activity relationship of a series of styrylpyridine analogs of MK-0476 (montelukast, Singulair) is described. This work has led to the identification of a number of potent and orally active cysLT1 receptor (LTD4 receptor) antagonists including 2ab (L-733,321) as an optimized candidate.

We have characterized the rat prostanoid EP1, EP2, EP3alpha and EP4 receptor subtypes cloned from spleen, hepatocyte and/or kidney cDNA libraries. Comparison of the deduced amino acid sequences of the rat EP receptors with their respective homologues from mouse and human showed 91% to 98% and 82% to 89% identity, respectively. Radioreceptor binding assays and functional assays were performed on EP receptor expressing human embryonic kidney (HEK) 293 cells. The KD values obtained with prostaglandin E2 for the prostanoid receptor subtypes EP1, EP2, EP3alpha and EP4 were approximately 24, 5, 1 and 1 nM, respectively. The rank order of affinities for various prostanoids at the prostanoid receptor subtypes EP2, EP3alpha and EP4 receptor subtypes was prostaglandin E2 = prostaglandin E1iloprostprostaglandin F2alphaprostaglandin D2U46619. The rank order at the prostanoid EP1 receptor was essentially the same except that iloprost had the highest affinity of the prostanoids tested. Of the selective ligands, butaprost was selective for prostanoid EP2, MB28767 and sulprostone were selective for EP3alpha and enprostil displayed dual selectivity, interacting with both prostanoid receptor subtypes EP1 and EP3alpha. All four receptors coupled to their predominant signal transduction pathways in HEK 293 cells. Notably, using a novel aequorin luminescence assay to monitor prostanoid EP1 mediated increases in intracellular calcium, both iloprost and sulprostone were identified as partial agonists. Finally, by Northern blot analysis EP3 transcripts were most abundant in liver and kidney whereas prostanoid EP2 receptor mRNA was expressed in spleen, lung and testis and prostanoid EP1 receptor mRNA transcripts were predominantly expressed in the kidney. The rat prostanoid EP1 probes also detected additional and abundant transcripts present in all the tissues examined. These were found to be related to the expression of a novel protein kinase gene and not the prostanoid EP1 gene [Batshake, B., Sundelin, J., 1996. The mouse genes for the EP1 prostanoid receptor and the novel protein kinase overlap. Biochem. Biophys. Res. Commun. 227. 1329-1333].

Background Domestic violence and abuse (DVA), defined as threatening behavior or abuse by adults who are intimate partners or family members, is a key public health and clinical priority. The prevalence of DVA in the United Kingdom and worldwide is high, and its impact on physical and mental health is detrimental and persistent. There is currently little support within healthcare settings for women experiencing DVA. Psychological problems in particular may be difficult to manage outside specialist services, as conventional forms of therapy such as counseling that do not address the violence may be ineffective or even harmful. The aim of this study is to assess the overall effectiveness and cost-effectiveness of a novel psychological intervention tailored specifically for survivors of DVA and delivered by domestic violence advocates based in third-sector organizations. Methods and study design This study is an open, pragmatic, parallel group, individually randomized controlled trial. Women ages 16 years and older experiencing domestic violence are being enrolled and randomly allocated to receive usual DVA agency advocacy support (control) or usual DVA agency support plus psychological intervention (intervention). Those in the intervention group will receive eight specialist psychological advocacy (SPA) sessions weekly or fortnightly, with two follow-up sessions, 1 month and then 3 months later. This will be in addition to any advocacy support sessions each woman receives. Women in the control group will receive usual DVA agency support but no additional SPA sessions. The aim is to recruit 250 women to reach the target sample size. The primary outcomes are psychological well-being and depression severity at 1 yr from baseline, as measured by the Clinical Outcomes in Routine Evaluation–Outcome Measure (CORE-OM) and the Patient Health Questionnaire (PHQ-9), respectively. Secondary outcome measures include anxiety, posttraumatic stress, severity and frequency of abuse, quality of life and cost-effectiveness of the intervention. Data from a subsample of women in both groups will contribute to a nested qualitative study with repeat interviews during the year of follow-up. Discussion This study will contribute to the evidence base for management of the psychological needs of women experiencing DVA. The findings will have important implications for healthcare commissioners and providers, as well as third sector specialist DVA agencies providing services to this client group. Trial registration ISRCTN58561170

A new class of potent ligand for the human peripheral cannabinoid (hCB 2 ) receptor is described. Two indole analogs 13 and 17 exhibited nanomolar potencies (K i ) with good selectivity for the hCB 2 receptor over the human central cannabinoid (hCB 1 ) receptor.

Structure-activity studies leading to the discovery of a new series of non-quinoline cysLT 1 receptor (LTD 4 receptor) antagonists are described. These studies demonstrated that the quinoline ring system of montelukast ( 5 ) may be replaced by an appropriately substituted thienopyridine system, yielding potent compounds. Two other molecular features of montelukast, the terminal phenyl ring substitution and the vinyl link, were also reevaluated. These studies led to the identification of 1 (L-740,515) , a compound with optimized in vitro and in vivo biological profiles.

A validated patient satisfaction survey for use with sexual health clinic attendees was used in 12 genitourinary (GU) medicine/sexual health clinics throughout the south-west region (UK). The questionnaire covers aspects of pre-appointment, performance of healthcare professionals, facilities and privacy, communication with respect, information on leaving and overall experience. Data from the 12 clinics are presented with mean performance scores and 95% confidence intervals (95% CI), as well as the experience of implementing the project across a region. There was a high level of satisfaction with overall quality of care: 86-100% rated the quality of care as either excellent or very good. Where clinics have performed below the 95% CI, it provides an opportunity to share good practice from the best performing clinics and to look at one's own processes and discuss as teams whether changes could be made that might improve outcomes. Other clinics might find it useful to use this questionnaire to look at their own performance and compare with these data. As medical re-validation for professional practice approaches, all doctors need to demonstrate that they have participated in collecting quality improvement data and implementing changes to service delivery; these data might provide a starting point.

Functional cDNA clones coding for three isoforms of the human prostaglandin E receptor EP3 subtype have been isolated from kidney and uterus cDNA libraries. The three isoforms, designated hEP3-I, hEP3-II and hEP3-III, have open reading frames corresponding to 390, 388 and 365 amino acids, respectively. They differ only in the length and amino acid composition of their carboxy-terminal regions, beginning at position 360. The human EP3 receptor has seven predicted transmembrane spanning domains and therefore belongs to the G-protein-coupled receptor family. The rank order of potency for prostaglandins and related analogs in competition for [3H]PGE2 specific binding to membranes prepared from transfected COS cells was comparable for all three isoforms, and as predicted for the EP3 receptor, with PGE2 = PGE1 >> PGF2 alpha = iloprost > PGD2 >> U46619. In addition, the EP3-selective agonist MB28767 was a potent competing ligand with an IC50 value of 0.3 nM, whereas the EP1-selective antagonist AH6909 gave IC50 values of 2-7 microM and the EP2-selective agonist butaprost was inactive. In summary, we have cloned three isoforms of the human EP3 receptor having comparable ligand binding properties.

A functional cDNA clone coding for the human prostaglandin E receptor EP1 subtype has been isolated from a human erythroleukemia cell cDNA library probed by low-stringency hybridization using a polymerase chain reaction fragment of the human thromboxane receptor. The human EP1 receptor is comprised of 402 amino acids with a predicted molecular mass of 41,858 and has the topography common to all G-protein-coupled receptors with seven predicted transmembrane spanning domains. Prostaglandin (PG) E2 challenge of Xenopus oocytes injected with EP1 cDNA resulted in an increase in intracellular Ca2+. In addition, the rank order of potency for prostaglandins in competition for [3H]PGE2 specific binding to membranes prepared from EP1 cDNA transfected COS cells was PGE2 > PGE1 > PGF2 alpha > PGD2. Furthermore, the EP1 receptor-selective antagonists AH 6809 and SC19220 were more potent than the EP2 receptor-selective agonist butaprost in these competition binding assays. In summary, therefore, we have cloned the human EP1 receptor subtype which is functionally coupled to an increase in intracellular Ca2+.

The human acute monocytic leukemia cell line THP-1 has been identified, by radioligand binding, as expressing the leukotriene D 4 receptor at a high level (4000 binding sites per cell), without the need for further cell differentiation. [ 3 H]Leukotriene D 4 -specific binding to THP-1 cell membranes was of high affinity ( K D = 0.47 nM) and saturable, enhanced by divalent cations but inhibited by both monovalent cations and non-hydrolyzable GTP analogs. The cysteinyl leukotrienes competed for [ 3 H]leukotriene D 4 -specific binding with the following rank order of potency: leukotriene D 4 ⪢ leukotriene E 4 〉 leukotriene C 4 In addition, leukotriene D 4 -receptor antagonists from two structural classes, the quinolines MK-571 and L-697,008, and the indole ICI 204,219, displayed nanomolar potency in [ 3 H]leukotriene D 4 competition assays. These data show that [ 3 H]leukotriene D 4 -specific binding to THP-1 cell membranes fulfils the criteria for binding to a leukotriene D 4 receptor regulated through interaction with a G protein. Several novel features of the THP-1 leukotriene D 4 receptor were investigated. Culture of THP-1 cells in the presence of tunicamycin, an inhibitor of N -glycosylation, resulted in a 6-fold decrease in the number of detectable [ 3 H]leukotriene D 4 -specific binding sites. Target-size analysis by radiation inactivation estimated a molecular mass of 65 kDa for the [ 3 H]leukotriene D 4 specific binding site(s) present in THP-1 cell membranes. Together, these results suggest that the human THP-1 cell leukotriene D 4 receptor is a glycosylated protein with a molecular mass of approx. 65 kDa within the membrane environment.

The leukotriene D4 receptor has been fully characterized by radioligand binding in membrane preparations from dimethyl sulphoxide-differentiated U937 cells, a human monocyte leukemia cell line, and, in parallel experiments, compared with leukotriene D4 receptor found in human lung and guinea-pig lung preparations. [3H]Leukotriene D4 specific binding in differentiated U937 cell membranes is of high affinity (KD = 0.35 nM), saturable (Bmax = 287 fmol/mg protein), with differentiation resulting in a 3–5-fold increase in the number of detectable binding sites. [3H]Leukotriene D4-specific binding in differentiated U937 cell membranes displays several features of G-protein-cupled receptors, being inhibited by GTP analogues and sodium ions, but increased by divalent cations. These characteristics are shared with [3H]leukotriene D4-specific binding in human and guinea-pig lung preparations. However, differences between these leukotriene D4 receptor types were observed. [3H]Leukotriene D4 equilibrium binding to differentiated U937 cell membranes could be dissociated to non-specific binding levels by 1000-fold excess of competing ligand, whereas binding to guinea-pig lung membranes was only partially dissociated under these conditions. In addition, differences in potency were demonstrated in competition studies with leukotriene E4 and leukotriene C4, although leukotriene D4 and the leukotriene D4-receptor antagonists MK-571 and ICI 204,219 were equipotent in competing for [3H]leukotriene D4-specific binding in all three membranes preparations. In conclusion, the leukotriene D4 receptor in differentiated U937 cell membranes resembles that in human lung, validating the use of this cell line as a suitable source of receptor in the development of potent specific antagonists.

Structure-activity studies leading to the discovery of a new series of non-quinoline cysLT 1 receptor (LTD 4 receptor) antagonists are described. These studies demonstrated that the quinoline ring system of montelukast ( 5 ) may be replaced by an appropriately substituted thienopyridine system, yielding potent compounds. Two other molecular features of montelukast, the terminal phenyl ring substitution and the vinyl link, were also reevaluated. These studies led to the identification of 1 (L-740,515) , a compound with optimized in vitro and in vivo biological profiles.

A new class of potent ligand for the human peripheral cannabinoid (hCB 2 ) receptor is described. Two indole analogs 13 and 17 exhibited nanomolar potencies (K i ) with good selectivity for the hCB 2 receptor over the human central cannabinoid (hCB 1 ) receptor.

A new, potent, orally active leukotriene D 4 receptor antagonist has been discovered. The structure -activity relationship leading to L-695,499 is described.

Verlukast (MK-679) (3-(((3-(2-(7-chloro-2-quinolinyl)-(E)-ethenyl)phenyl)((3-(dimethylamino)-3-oxopropyl)thio)methyl)-thio)propionic acid) is a potent and selective inhibitor of [3H]leukotriene D4 binding in guinea-pig (IC50 = 3.1 ± 0.5 nM) and human (IC50 = 8.0 ± 3.0 nM) lung homogenates and dimethyl sulfoxide differentiated U937 cell membrane preparations (IC50 = 10.7 ± 1.6 nM) but is essentially inactive versus [3H]leukotriene C4 binding in guinea-pig lung homogenates (IC50 values of 19 and 33 μM). Functionally, when tested at 60 nM, it antagonized contractions of guinea-pig trachea (GPT) induced by leukotriene C4, leukotriene D4, and leukotriene E4 (respective −log KB values of 8.6, 8.8, and 8.9) and contractions of human trachea (HT) induced by leukotriene D4 (−log KB value 8.3 ± 0.2). In contrast, verlukast (20–200 nM) failed to antagonize contractions of GPT induced by leukotriene C4 in the presence of 45 mM L-serine borate. Intravenous (i.v.) and aerosol verlukast antagonized bronchoconstriction (BC) induced in anaesthetized guinea pigs by i.v. leukotriene D4 but did not block BC to arachidonic acid or histamine. Intraduodenal verlukast (0.25 mg/kg) antagonized leukotriene D4 (0.2 μg/kg) induced BC in guinea pigs. Oral and aerosol administration blocked leukotriene D4-induced BC in conscious squirrel monkeys. Orally administered compound also blocked ovalbumin-induced BC in conscious sensitized rats treated with methysergide (3 μg/kg). The pharmacological profile for verlukast is similar to that of the racemic compound, MK-571. Verlukast is currently in clinical development for the treatment of asthma and related diseases.Key words: verlukast, MK-679, leukotriene D4 antagonist, airway smooth muscle.

A [3H]leukotriene D4 radioreceptor binding assay has been established in rat lung and has been used to fully characterize the leukotriene D4 receptor in lung membranes from an inbred strain of rats displaying non-specific bronchial hyperreactivity. [3H]leukotriene D4 specific binding in this tissue is of high affinity (KD 0.12 nM), saturable (Bmax 42 fmol/mg protein), inhibited by both guanine nucleotide analogues and sodium ions and increased by divalent cations. In addition, Ki values show that agonists, but not antagonists, compete for [3H]leukotriene D4 binding in rat lung with the same potency as they compete for [3H]leukotriene D4 binding in guinea-pig lung, the classical tissue for leukotriene D4 receptor studies. Finally, [3H]leukotriene D4 binding in hyperreactive rat lung has been compared with [3H]leukotrien D4 binding in lung tissue from Fischer rats, which are a less responsive strain.

To gain insight into the role of prostanoids in human kidney function, we examined the distribution of cyclooxygenase (COX) 1 and COX-2 by immunofluorescence and immunohistochemistry in human kidneys from adults of various age groups. COX-1 was detected in the collecting ducts, thin loops of Henle and portions of the renal vasculature. COX-2 was detected in the renal vasculature, medullary interstitial cells, and the macula densa. In addition, COX-2 immunoreactivity was noted in afferent arteries and the macula densa of the renal cortex and was more evident in the kidneys of older adults.

Synenkephalin (SYN), the nonopioid amino-terminal portion of proenkephalin (PRO), is stable and well conserved in mammals and therefore a promising marker for PRO systems. We immunized rabbits with synthetic [Tyr63]SYN(63-70)-octapeptide, coupled by glutaraldehyde to bovine serum albumin. In radioimmunoassay (RIA) using antiserum no. 681, [Tyr63]SYN(63-70)-octapeptide as standard, and 125I-[Tyr63]SYN(63-70)-octapeptide as tracer, the IC50 was approximately 51 fmol/100-microliters sample at equilibrium or 12 fmol/100 microliters in disequilibrium, and the sensitivity was approximately 3 fmol/100 microliters. Cross-reactivity of the assay was 100% with [Cys63]SYN(63-70)-octapeptide and with bovine adrenal 8.6-kilodalton peptide digested with trypsin and carboxypeptidase B, but less than 0.1% with transforming growth factor-alpha, less than or equal to 2 x 10(-6) with Leu-Leu-Ala [SYN(68-70)-tripeptide], and much less than 10(-6) with all other peptides tested. Therefore in RIA this antiserum is specific for the free carboxyl terminus of SYN. Because the peptide detected after enzyme digestion is the complete SYN(63-70)-octapeptide, we refer to the RIA as an assay for SYN(63-70). Tissue extracts were made in 1 M acetic acid, dried, reconstituted in Tris-CaCl2, and digested sequentially with trypsin plus carboxypeptidase B. Extracts from bovine corpus striatum gave SYN(63-70) RIA dilution curves parallel to the standard curve both before and after digestion. Digestion increased the amount of immunoreactive SYN(63-70) in striatum by a factor of 1.5-2.0. The ratio of total immunoreactive [Met5]enkephalin to total immunoreactive SYN(63-70) (after sequential digestion) was approximately 6:1. At least 90% of the immunoreactive SYN(63-70) in extracts of bovine caudate nucleus eluted from Sephadex G-100 with an apparent molecular weight equal to that of bovine PRO(1-77). Using the new RIA we were able to detect and characterize SYN processing for the first time in extracts of whole rat brain, human globus pallidus, and human pheochromocytoma. Results in these tissues were similar to those in cattle, in that most stored SYN had been processed to a free carboxyl terminus. Since the C-terminal octapeptide of SYN is practically identical in all known mammalian PRO, antiserum no. 681 should be useful for detecting, measuring, and purifying SYN from various mammals, including human beings.

Laropiprant is a selective antagonist of the prostaglandin D(2) (PGD(2)) receptor subtype 1 (DP1). Three double-blind, randomized, placebo-controlled studies evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of single and multiple oral doses of laropiprant in healthy male volunteers. Single doses up to 900 mg and multiple doses up to 450 mg were generally well tolerated. Laropiprant exhibited dose-proportional pharmacokinetics. Oral absorption is rapid (T(max)=0.8-2.0 h) and the terminal half-life is approximately 12-18 h. The pharmacokinetics of laropiprant was not affected by food. Single doses of 6 mg and higher were effective in suppressing PGD(2)-induced cyclic AMP accumulation in platelets, demonstrating laropiprant target engagement with DP1. Laropiprant has detectable off-target antagonist effects at the thromboxane A(2) receptor but no clinically significant effect on collagen-induced platelet aggregation or bleeding times with multiple doses up to 200 mg.