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1.
Mucosal Immunol ; 12(4): 930-944, 2019 07.
Article in English | MEDLINE | ID: mdl-31105269

ABSTRACT

Gut microbial translocation contributes to alcoholic hepatitis. Using a mouse model of alcoholic hepatitis, we investigated the effects of chronic alcohol plus binge and found increased abundance of Paneth cells and IL-17A in the proximal small intestine (PSI). Alcohol increased IL-17A production and pro-apoptotic signaling evidenced by Bax, Bim, caspase-3, and caspase-8 increases via endoplasmic reticulum (ER) stress indicated by C/EBP homologous protein (CHOP) upregulation; this was prevented by the ER stress inhibitor, 4-PBA, in isolated crypts in vitro and in vivo. Mechanistically, IL-17 augmented alcohol-induced ER stress in isolated crypts. In vivo IL-17A blocking antibody administration in alcohol-treated mice attenuated ER stress-mediated apoptosis and IL-18 induction and prevented alcohol-induced impairment of tight junctions in the PSI and LPS translocation to the liver. Acute-on-chronic alcohol resulted in inflammasome activation, caspase-1 cleavage, and IL-18 production in the PSI. In vivo treatment with antibiotics or 4-PBA prevented CHOP upregulation and inflammasome activation. Our data suggest that alcohol upregulates innate immune mechanisms by increasing Paneth cell numbers and IL-17A release contributing to apoptosis amplification, inflammasome activation, and gut leakiness in the PSI. Binge alcohol-induced Paneth cell expansion, ER stress, and inflammasome activation in the PSI are modulated by the gut microbiome.


Subject(s)
Apoptosis , Endoplasmic Reticulum Stress , Inflammasomes/metabolism , Interleukin-17/biosynthesis , Interleukin-18/metabolism , Intestine, Small/metabolism , Paneth Cells/metabolism , Alcohol Drinking , Animals , Apoptosis/drug effects , Biopsy , Caspases/metabolism , Cell Degranulation , Endoplasmic Reticulum Stress/drug effects , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Mice , Paneth Cells/drug effects , Signal Transduction , Transcription Factor CHOP/metabolism
2.
J Clin Microbiol ; 54(8): 2201-3, 2016 08.
Article in English | MEDLINE | ID: mdl-27307453

ABSTRACT

The detection of Mycoplasma genitalium was evaluated on 1,080 urine samples by the use of a Panther instrument. Overall sensitivity, specificity, positive predictive values, and negative predictive values were 100%, 99.4%, 93.6%, and 100%, respectively. Detection of M. genitalium by the use of the Panther transcription-mediated amplification assay offers a simple, accurate, and sensitive platform for diagnostic laboratories.


Subject(s)
Mycoplasma Infections/diagnosis , Mycoplasma genitalium/isolation & purification , Nucleic Acid Amplification Techniques/methods , Urine/microbiology , Female , Humans , Male , Mycoplasma genitalium/genetics , Predictive Value of Tests , Pregnancy , Sensitivity and Specificity , Transcription, Genetic , Urethritis/etiology , Urethritis/microbiology
4.
MAbs ; 7(5): 829-37, 2015.
Article in English | MEDLINE | ID: mdl-26230385

ABSTRACT

QBP359 is an IgG1 human monoclonal antibody that binds with high affinity to human CCL21, a chemokine hypothesized to play a role in inflammatory disease conditions through activation of resident CCR7-expressing fibroblasts/myofibroblasts. The pharmacokinetics (PK) and pharmacodynamics (PD) of QBP359 in non-human primates were characterized through an integrated approach, combining PK, PD, immunogenicity, immunohistochemistry (IHC) and tissue profiling data from single- and multiple-dose experiments in cynomolgus monkeys. When compared with regular immunoglobulin typical kinetics, faster drug clearance was observed in serum following intravenous administration of 10 mg/kg and 50 mg/kg of QBP359. We have shown by means of PK/PD modeling that clearance of mAb-ligand complex is the most likely explanation for the rapid clearance of QBP359 in cynomolgus monkey. IHC and liquid chromatography mass spectrometry data suggested a high turnover and synthesis rate of CCL21 in tissues. Although lymphoid tissue was expected to accumulate drug due to the high levels of CCL21 present, bioavailability following subcutaneous administration in monkeys was 52%. In human disease states, where CCL21 expression is believed to be expressed at 10-fold higher concentrations compared with cynomolgus monkeys, the PK/PD model of QBP359 and its binding to CCL21 suggested that very large doses requiring frequent administration of mAb would be required to maintain suppression of CCL21 in the clinical setting. This highlights the difficulty in targeting soluble proteins with high synthesis rates.


Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacokinetics , Chemokine CCL21/antagonists & inhibitors , Immunoglobulin G/immunology , Immunoglobulin G/pharmacology , Animals , Antibody Affinity , Chromatography, Liquid , Humans , Immunohistochemistry , Macaca fascicularis , Mass Spectrometry
6.
Clin Exp Allergy ; 44(11): 1371-85, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25200415

ABSTRACT

BACKGROUND: Using a monoclonal antibody with greater affinity for IgE than omalizumab, we examined whether more complete suppression of IgE provided greater pharmacodynamic effects, including suppression of skin prick responses to allergen. OBJECTIVE: To explore the pharmacokinetics, pharmacodynamics and safety of QGE031 (ligelizumab), a novel high-affinity humanized monoclonal IgG1κ anti-IgE. METHODS: Preclinical assessments and two randomized, placebo-controlled, double-blind clinical trials were conducted in atopic subjects. The first trial administered single doses of QGE031 (0.1-10 mg/kg) or placebo intravenously, while the second trial administered two to four doses of QGE031 (0.2- 4 mg/kg) or placebo subcutaneously at 2-week intervals. Both trials included an open-label omalizumab arm. RESULTS: Sixty of 73 (82%) and 96 of 110 (87%) subjects completed the intravenous and subcutaneous studies, respectively. Exposure to QGE031 and its half-life depended on the QGE031 dose and serum IgE level. QGE031 had a biexponential pharmacokinetic profile after intravenous administration and a terminal half-life of approximately 20 days. QGE031 demonstrated dose- and time-dependent suppression of free IgE, basophil FcεRI and basophil surface IgE superior in extent (free IgE and surface IgE) and duration to omalizumab. At Day 85, 6 weeks after the last dose, skin prick wheal responses to allergen were suppressed by > 95% and 41% in subjects treated subcutaneously with QGE031 (2 mg/kg) or omalizumab, respectively (P < 0.001). Urticaria was observed in QGE031- and placebo-treated subjects and was accompanied by systemic symptoms in one subject treated with 10 mg/kg intravenous QGE031. There were no serious adverse events. CONCLUSION AND CLINICAL RELEVANCE: These first clinical data for QGE031, a high-affinity IgG1κ anti-IgE, demonstrate that increased suppression of free IgE compared with omalizumab translated to superior pharmacodynamic effects in atopic subjects, including those with high IgE levels. QGE031 may therefore benefit patients unable to receive, or suboptimally treated with, omalizumab.


Subject(s)
Anti-Allergic Agents/pharmacology , Anti-Allergic Agents/therapeutic use , Antibodies, Anti-Idiotypic/pharmacology , Antibodies, Anti-Idiotypic/therapeutic use , Hypersensitivity, Immediate/drug therapy , Hypersensitivity, Immediate/immunology , Immunoglobulin E/immunology , Adolescent , Adult , Antibodies, Monoclonal, Humanized , Antibody Affinity/immunology , Drug Evaluation, Preclinical , Female , Humans , Hypersensitivity, Immediate/diagnosis , Immunoglobulin E/blood , Male , Middle Aged , Skin Tests , Treatment Outcome , Young Adult
7.
CPT Pharmacometrics Syst Pharmacol ; 3: e116, 2014 May 28.
Article in English | MEDLINE | ID: mdl-24872204

ABSTRACT

Population or other pharmacometric models are a useful means to describe, succinctly, the relationships between drug administration, exposure (concentration), and downstream changes in pharmacodynamic (PD) biomarkers and clinical endpoints, including the mixed effects of patient factors and random interpatient variation (fixed and random effects). However, showing a set of covariate equations to a drug development team is perhaps not the best way to get a message across. Visualization of the consequences of the knowledge encapsulated within the model is the key component. Yet in many instances, it can take hours, perhaps days, to collect ideas from teams, write scripts, and run simulations before presenting the results-by which time they have moved on. How much better, then, to seize the moment and work interactively to decide on a course of action, guided by the model. We exemplify here the visualization of pharmacometric models using the Berkeley Madonna software with a particular focus on interactive sessions. The examples are provided as Supplementary Material.

8.
Ecol Appl ; 23(3): 537-45, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23734484

ABSTRACT

In a 10-year study, we assessed the influence of five carbon (C) treatments on the labile C and nitrogen (N) pools of historically N-enriched plots on the Shortgrass Steppe Long Term Ecological Research site located in northeastern Colorado. For eight years, we applied sawdust, sugar, industrial lignin, sawdust + sugar, and lignin + sugar to plots that had received N and water additions in the early 1970s. Previous work showed that past water and N additions altered plant species composition and enhanced rates of nutrient cycling; these effects were still apparent 25 years later. We hypothesized that labile C amendments would stimulate microbial activity and suppress rates of N mineralization, whereas complex forms of carbon (sawdust and lignin) could enhance humification and lead to longer-term reductions in N availability. Results indicated that, of the five carbon treatments, sugar, sawdust, and sawdust + sugar suppressed N availability, with sawdust + sugar being the most effective treatment to reduce N availability. The year after treatments stopped, N availability remained less in the sawdust + sugar treatment plots than in the high-N control plots. Three years after treatments ended, reductions in N availability were smaller (40-60%). Our results suggest that highly labile forms of carbon generate strong short-term N sinks, but these effects dissipate within one year of application, and that more recalcitrant forms reduce N longer. Sawdust + sugar was the most effective treatment to decrease exotic species canopy cover and increase native species density over the long term. Labile carbon had neither short- nor long-term effects on exotic species. Even though the organic amendments did not contribute to recovery of the dominant native species Bouteloua gracilis, they were effective in increasing another native species, Carex eleocharis. These results indicate that organic amendments may be a useful tool for restoring some native species in the shortgrass steppe, though not all.


Subject(s)
Carbon/pharmacology , Ecosystem , Nitrogen/chemistry , Plants/drug effects , Colorado , Nitrogen/metabolism , Plants/classification , Species Specificity , Time Factors
9.
Br J Dermatol ; 169(4): 869-79, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23662922

ABSTRACT

BACKGROUND: Multiphoton microscopy (MPM) is a novel imaging technology that has recently become applicable for diagnostic purposes. The use of (near) infrared light in MPM allows for deep tissue imaging. In addition, this modality exploits the autofluorescent nature of extracellular matrix fibres within the skin. OBJECTIVES: To quantitate the structure and abundance of elastic fibres in human dermis in three dimensions utilizing autofluorescent signals generated by MPM for the objective examination of elastin-related skin disorders. METHODS: Cross-sections of skin samples from elastin-related disorders were analysed by MPM and correlated to histopathology. In situ visualization of elastic fibres by MPM was conducted by en face imaging of ex vivo skin samples through the intact epidermis. Image analysis software was used to quantify elastic fibres in three dimensions. RESULTS: Based on the MPM-detected elastin-specific autofluorescence, we developed the Dermal Elastin Morphology Index (DEMI), calculated as the ratio of elastic fibre surface area and volume. This enabled objective three-dimensional quantification of elastic fibres. Quantitative scoring of sun-damaged skin using DEMI correlated with qualitative histopathological grading of the severity of solar elastosis. Furthermore, this approach was applied to changes in elastic fibre architecture in other disorders, such as pseudoxanthoma elasticum (PXE), PXE-like syndrome, elastofibroma, focal dermal elastosis, anetoderma, mid-dermal elastolysis and striae distensae. We imaged elastic fibres in intact ex vivo skin imaged en face through the epidermis, indicating that this approach could be used in vivo. CONCLUSIONS: MPM has the potential for noninvasive in vivo visualization of elastic fibres in the dermis with near histological resolution. DEMI allows objective assessment of elastic fibres to support diagnosis and monitoring of disease progress or therapy of elastin-related skin disorders.


Subject(s)
Elastin/metabolism , Skin Diseases/pathology , Adult , Aged , Aged, 80 and over , Humans , Imaging, Three-Dimensional , Microscopy, Fluorescence, Multiphoton , Middle Aged , Pseudoxanthoma Elasticum/pathology
10.
Article in English | MEDLINE | ID: mdl-23835885

ABSTRACT

Canakinumab, an anti-interleukin-1ß (IL-1ß) monoclonal antibody, is approved for cryopyrin-associated periodic syndromes and is under investigation for the management of other inflammatory disorders. In this study, population-based pharmacokinetic-pharmacodynamic models were developed to understand responses to canakinumab in patients with rheumatoid arthritis (RA). Total canakinumab and total IL-1ß concentrations were obtained from four clinical trials (n = 472). In contrast to traditional models, free IL-1ß concentrations were calculated and used to link canakinumab to changes in C-reactive protein (CRP) concentrations and American College of Rheumatology (ACR) scores of 20, 50, and 70% improvement. Temporal patterns of total canakinumab, total IL-1ß, CRP, and ACR scores were all well described. Simulations confirmed that 150 mg every 4 weeks improved ACR scores in patients with RA, but no additional benefit was provided by higher doses or more frequent administration. Integrating predicted endogenous free ligand concentrations with biomarkers and clinical outcomes could be extended to new therapies of anti-inflammatory diseases.CPT: Pharmacometrics & Systems Pharmacology (2012) 1, e5; doi:10.1038/psp.2012.6; advance online publication 26 September 2012.

12.
Vet Rec ; 169(14): 354-6, 2011 Oct 01.
Article in English | MEDLINE | ID: mdl-21965239
14.
Vet Rec ; 169(12): 302-3, 2011 Sep 17.
Article in English | MEDLINE | ID: mdl-21926138
16.
Clin Pharmacol Ther ; 87(4): 492-6, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20147897

ABSTRACT

Posology--the science of dose and regimen--is a critical part of drug development. It is concerned with ensuring that patients experience significant clinical benefit without intolerable adverse effects. It has become apparent, in the case of certain biologics, that one can directly quantitate occupancy or target capture and relate these to clinical responses. With mathematical models that integrate binding concepts with clinical effects, potential posologies can be quickly explored through simulation, thereby liberating research teams from the traditional constraints and simultaneously stimulating innovation.


Subject(s)
Biological Products/pharmacology , Drug Design , Models, Biological , Biological Products/administration & dosage , Biological Products/adverse effects , Clinical Trials as Topic/methods , Computer Simulation , Dose-Response Relationship, Drug , Humans
17.
Int J STD AIDS ; 21(1): 60-2, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20029066

ABSTRACT

The aim of this review was to evaluate an 'Email a Clinician' link on a medically reviewed sexual health website, which was established to allow general practitioners (GPs) to communicate remotely with sexual health clinic specialists. The website was developed in consultation with GPs and extensively promoted throughout the relevant professional primary health-care networks. Despite this, the email link appeared to fail in its objective of facilitating GP access to specialist sexual health physician opinion within five working days. An audit examining use of the email link was conducted for a one-year period, during which time 324 emails were received. Results showed that the bulk of the emails (93.2%) were spam, and only 6.8% were genuine enquiries. Of the 22 genuine emails, 21 (95%) originated from the general public and there were no enquiries from the GPs, who were the target audience of the website, resulting in removal of the email link from the site. Direct survey of local GPs to evaluate reasons for non-utilization of the link was not possible. However, discomfort with the technology, time added to existing workload, lack of direct perceived benefit and lack of immediate response have been cited as contributing factors that may limit widespread adoption of other telemedicine services. As a new generation of recently graduated GPs enters the Australian workforce, who might be expected to be skilled and comfortable with electronic medical communication, the option of a direct email link to a sexual health clinic, with a faster turnaround time, may be worth re-visiting in the future.


Subject(s)
Attitude of Health Personnel , Electronic Mail/statistics & numerical data , Internet/statistics & numerical data , Physicians, Family , Remote Consultation/methods , Sexually Transmitted Diseases/diagnosis , Australia , Humans , Quality Assurance, Health Care/standards , Quality Assurance, Health Care/statistics & numerical data
18.
Curr Pharm Biotechnol ; 9(6): 502-9, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19075688

ABSTRACT

Recent advances in combinatorial protein engineering have made it possible to develop antibody-based and non-Ig protein scaffolds that can potentially substitute for most whole antibody-associated properties. In theory, many different natural human protein backbones are suitable to be used as recombinant templates for engineering : antibody-derived scaffolds, carrier proteins that display a single binding interface, backbones that provide a rigid core structure suitable for grafting loops or protein scaffolds allowing the incorporation of variable loops in a favorable 3D configuration. In practice however, only a few have yielded the necessary properties to be translated into 'druggable Biologicals'. Amongst these properties, potential broad specificities towards any kind of target, ease of production, small size, good tolerability and low immunogenicity are essential and will be discussed in this review. Intellectual property is another key issue for the development of these protein scaffolds; although circumventing antibody-associated patents is often a major if not primary goal, clear advantages compared to whole antibodies must be presented to translate scaffold discovery into successful therapeutic drug candidates. In this review, a particular emphasis will be given to the most validated scaffolds that have reached the clinical development phase. Although the question of their immunogenicity is still open, preliminary clinical data do not point to any particular adverse immunogenic reactions although these are highly dependent on dosage, administration route and therapeutic indication. Finally, some of the emerging Biotechs developing protein scaffolds have been associated during the last two years with successful acquisitions by Big Pharmas and we will speak on the perspective positions of these proteins within the global Biologicals market.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Biomedical Research/trends , Clinical Trials as Topic/trends , Diagnostic Imaging/methods , Protein Engineering/trends , Contrast Media
19.
Xenobiotica ; 37(10-11): 1331-54, 2007.
Article in English | MEDLINE | ID: mdl-17968748

ABSTRACT

The drug development process is divided into phases with decisions required on compound selection and promotion to each subsequent development phase. In preclinical drug development the main objective is to bring the compound into human trials and there is an inability of many preclinical information packages to predict clinical responses. Since clinical responses are functions of the dose, the human dose anticipation should be a key deliverable of any preclinical package of drug candidate. The human dose should be anticipated by integration of information from multiple sources, in vitro and in vivo, non-human and human, using a variety of methodologies and approaches. Prediction of human safe and active dose relies on the availability of validated animal models for effect. Although there are many exceptions to the rule, the paper defines a four-step approach for the anticipation of human dose for first-in-man trials: 1, characterization of non-human exposure-response relationships; 2, correction for interspecies differences; 3, diagnosing compound absorption, distribution, metabolism and excretion (ADME) properties and prediction of human pharmacokinetics; and 4, prediction of human dose-responses and dose selection for phase I protocols.


Subject(s)
Drug Design , Animals , Biological Transport, Active , Clinical Trials, Phase I as Topic/methods , Humans , In Vitro Techniques , Models, Biological , Pharmaceutical Preparations/administration & dosage , Xenobiotics/administration & dosage , Xenobiotics/pharmacokinetics , Xenobiotics/pharmacology
20.
Eur J Anaesthesiol ; 23(3): 197-201, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16430790

ABSTRACT

BACKGROUND AND OBJECTIVE: The glutamate-nitric oxide-cyclic guanosine monophosphate pathway has been identified as a potential target for anaesthetic agents. However, mice deficient in neuronal nitric oxide synthase have a similar susceptibility to volatile anaesthetic agents to wild-type mice and are not affected by non-isoform selective inhibitors. We hypothesized that the neuronal nitric oxide synthase selective inhibitor, 7-nitroindazole, would also reduce the propofol requirements in wild-type mice but would have no effect in neuronal nitric oxide synthase knockout mice. METHODS: We determined the time to loss of righting reflex, time to painful stimulus and time to regaining the righting reflex in neuronal nitric oxide synthase knockout and wild-type mice following the intraperitoneal injection of propofol in untreated, 7-nitroindazole and vehicle only treated animals (n = 6 per group). Propofol (200 mg kg(-1)) resulted in loss of righting reflex in the untreated and vehicle only groups but was lethal in 7-nitroindazole pre-treated mice, requiring a reduced dose of propofol (100 mg kg(-1)). RESULTS: 7-nitroindazole pre-treatment significantly reduced the loss of righting reflex (P < 0.001) in both wild-type and knockout mice when compared to untreated and vehicle only pre-treated animals, but had no effect on time to painful stimulus or regaining of the righting reflex. 7-nitroindazole reduced the propofol requirements in knockout mice to the same extent as in wild-type animals. CONCLUSIONS: Propofol exerts its anaesthetic effects at least partially via the glutamate-nitric oxide-cyclic guanosine monophosphate pathway. The neuronal nitric oxide synthase knockout mice are sensitive to neuronal nitric oxide synthase selective inhibition suggesting that compensatory pathways in neuronal nitric oxide synthase knockout mice exist.


Subject(s)
Anesthetics, Intravenous/pharmacology , Enzyme Inhibitors/pharmacology , Indazoles/pharmacology , Nitric Oxide Synthase Type I/antagonists & inhibitors , Nitric Oxide Synthase Type I/genetics , Propofol/pharmacology , Anesthetics, Intravenous/administration & dosage , Animals , DNA Primers , Drug Resistance/genetics , Mice , Mice, Knockout , Neomycin/pharmacology , Postural Balance/drug effects , Propofol/administration & dosage , Reflex/drug effects , Reverse Transcriptase Polymerase Chain Reaction
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