Publications by authors named "Markham P"

Mycoplasma gallisepticum causes chronic respiratory disease in poultry. A novel vaccine, Vaxsafe MG304 (the ts-304 strain), has greater protective efficacy in chickens than the Vaxsafe MG (strain ts-11) vaccine when delivered by eye drop at 3 weeks of age. Applying this vaccine in the hatchery to 1-day-old birds, using mass administration methods, would improve animal welfare and reduce labour costs associated with handling individual birds.

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Background: The utility of early metabolic response assessment to guide selection of the systemic component of definitive chemoradiotherapy (dCRT) for oesophageal cancer is uncertain.

Methods: In this multi-centre, randomised, open-label, phase II substudy of the radiotherapy dose-escalation SCOPE2 trial we evaluated the role of F-Fluorodeoxyglucose positron emission tomography (PET) at day 14 of cycle 1 of three-weekly induction cis/cap (cisplatin (60 mg/m)/capecitabine (625 mg/m days 1-21)) in patients with oesophageal squamous cell carcinoma (OSCC) or adenocarcinoma (OAC). Non-responders, who had a less than 35% reduction in maximum standardised uptake value (SUV) from pre-treatment baseline, were randomly assigned to continue cis/cap or switch to car/pac (carboplatin AUC 5/paclitaxel 175 mg/m) for a further induction cycle, then concurrently with radiotherapy over 25 fractions.

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Prophylactic use of antimicrobials after administration of live vaccines is a common practice in the poultry industry, but the impact of this on the efficacy and duration of protection induced by the vaccines is unknown. The effect of treatment with tylosin on the efficacy of vaccination with the live attenuated M. gallisepticum strain, Vaxsafe MG ts-304, was examined.

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This study quantified the distribution of nerves and adjacent anatomies surrounding human common hepatic artery (CHA) as guidance for catheter based denervation. CHA collected from cadaveric human donors (n = 20) were histologically evaluated and periarterial dimensions and distributions of nerves, lymph nodes, pancreas and blood vessels quantified by digital morphometry. Nerve abundance decreased significantly with distance from the aortic ostium (P < 0.

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MalF has been shown to be required for virulence in the important avian pathogen To characterize the function of MalF, predicted to be part of a putative ABC transporter, we compared metabolite profiles of a mutant with a transposon inserted in (MalF-deficient ST mutant 04-1; Δ) with those of wild-type bacteria using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Of the substrates likely to be transported by an ABC transport system, glycerol was detected at significantly lower abundance in the Δ mutant, compared to the wild type. Stable isotope labeling using [U-C]glycerol and reverse transcription-quantitative PCR analysis indicated that MalF was responsible for the import of glycerol into and that, in the absence of MalF, the transcription of , which encodes a second transporter, GtsA, was upregulated, potentially to increase the import of glycerol-3-phosphate into the cell to compensate for the loss of MalF.

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causes serious infections in ruminants, leading to huge economic losses. Lipoproteins are key components of the mycoplasma membrane and are believed to function in nutrient acquisition, adherence, enzymatic interactions with the host, and induction of the host's immune response to infection. Many genes of have not been assigned functions, in part because of their low sequence similarity with other bacteria, making it difficult to extrapolate gene functions.

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Mycoplasma gallisepticum (MG) is an important pathogen of poultry worldwide, causing chronic respiratory disease in chickens and turkeys. MG ts-304 is a GapA positive clone recovered from Vaxsafe MG (strain ts-11) that has been shown to be safe in chickens when delivered by the eye drop route to 3-week-old specific-pathogen-free chickens and to confer protection against challenge at 4 weeks after vaccination, as measured by tracheal mucosal thickness and air sac lesion scores. In this study, specific pathogen-free chickens (SPF) were vaccinated with a single dose of the MG ts-304 vaccine (10 colour changing units) at 3 weeks of age and experimentally challenged by aerosol with the virulent M.

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Respiratory infections caused by Actinobacillus pleuropneumoniae have a large impact on commercial pig farms globally. As current vaccines have limited efficacy, animal care and air hygiene are critical for disease control. Here we used a Coriolis μ cyclonic air sampler and an A.

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Paclitaxel coated balloon catheters (PCB) were developed as a polymer-free non-implantable alternative to drug eluting stents, delivering similar drug payloads in a matter of minutes. While PCB have shown efficacy in treating peripheral arterial disease in certain patient groups, restenosis rates remain high and there is no class effect. To help further optimize these devices, we developed a scanning electron microscopy (SEM) imaging technique and computational modeling approach that provide insights into the coating micromorphology dependence of in vivo drug transfer and retention.

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Vaxsafe MG (strain ts-11) is a live attenuated vaccine against the important poultry pathogen Mycoplasma gallisepticum that has been used globally to improve poultry health. However, the majority of the bacterial cells in Vaxsafe MG do not express the GapA cytadhesin, reducing their capacity to colonise the respiratory tract. Vaxsafe MG (strain ts-304) is a GapA positive clone recovered from Vaxsafe MG (strain ts-11) that has been shown to be safe and efficacious in turkeys, and preliminary studies have suggested that Vaxsafe MG (strain ts-304) may have greater efficacy in chickens than Vaxsafe MG (ts-11).

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The survival, replication, and virulence of mycoplasmas depend on their ability to capture and import host-derived nutrients using poorly characterized membrane proteins. Previous studies on the important bovine pathogen demonstrated that the amino-terminal end of an immunogenic 226-kDa (P226) protein, encoded by (the full-length product of which has a predicted molecular weight of 303 kDa), had lipase activity. The predicted sequence of MilA contains glycosaminoglycan binding motifs, as well as multiple copies of a domain of unknown function (DUF445) that is also found in apolipoproteins.

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This study sought to evaluate perisplenic artery nerve distribution and the feasibility of splenic artery denervation (SDN). The NEXION radiofrequency catheter was used to perform SDN in healthy and inflammatory arthritis pigs. Splenic artery anatomy, nerve distribution, and splenic norepinephrine (NEPI) levels were evaluated before and after SDN.

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Radiofrequency renal denervation is under investigation for treatment of hypertension with variable success. We developed preclinical models to examine the dependence of ablation biomarkers on renal denervation treatment parameters and anatomic variables. One hundred twenty-nine porcine renal arteries were denervated with an irrigated radiofrequency catheter with multiple helically arrayed electrodes.

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Mycoplasma bovis is an economically important pathogen of the cattle industry worldwide, and there is an urgent need for a more effective vaccine to control the diseases caused by this organism. Although the M. bovis genome sequence is available, very few gene functions of M.

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Avian pathogenic Escherichia coli (APEC) cause widespread economic losses in poultry production and are potential zoonotic pathogens. Genome sequences of 95 APEC from commercial poultry operations in four Australian states that carried the class 1 integrase gene intI1, a proxy for multiple drug resistance (MDR), were characterized. Sequence types ST117 (22/95), ST350 (10/95), ST429 and ST57 (each 9/95), ST95 (8/95) and ST973 (7/95) dominated, while 24 STs were represented by one or two strains.

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Mycoplasma gallisepticum is an economically important pathogen of commercial poultry. An improved understanding of M. gallisepticum pathogenesis is required to develop better control methods.

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Background: Inexpensive and convenient diagnostic tests for use in clinical work and for the surveillance of infection with Mycoplasma bovis are in demand. The objective of this longitudinal field study was to gain knowledge about the dynamics of antibodies against M. bovis in sera from naturally exposed calves with and without different clinical signs, measured by two different ELISA tests.

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Mycoplasma gallisepticum (MG) is an important pathogen of poultry worldwide that causes chronic respiratory disease (CRD) in chickens and infectious sinusitis in turkeys. Vaxsafe MG (strain ts-11) is a live attenuated temperature sensitive vaccine that has been proven to be effective in controlling CRD in chickens, but it is not efficacious in turkeys. The gapA gene, which encodes a mature cytadhesin protein with a molecular weight of approximately 105 kDa, is not expressed in strain ts-11 because a 20 base pair reiterated sequence introduces a frame shift and causes premature truncation of the translated peptide.

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The temperature-sensitive (ts+) Mycoplasma synoviae vaccine strain MS-H harbors a non-synonymous mutation which results in Glycine to Arginine substitution at position 123 in the highly conserved glycine-rich motif of Obg-fold in the GTP-binding protein Obg. In-silico analysis of the wild-type and mutant Obgs of M. synoviae has indicated that this amino acid substitution affects structure of the protein, potentially leading to abrogation of Obg function in vivo.

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is associated with several clinical syndromes of cattle. Currently, limited information is available on the sensitivity () and specificity () of serological assays used for the detection of -specific antibodies. Consequently, it is difficult to critically evaluate the outcomes of studies that use these assays.

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Background: Innovations in drug eluting stent designs make it increasingly important to develop models for differentiating performance through spatial definition of drug, receptor binding and cell state.

Methods: Two designs of sirolimus analog eluting stents were implanted into porcine coronary arteries for 28, 60 or 90 days (n = 9/time point), durable coating (Xience) and deployable absorbable coating (MiStent). Explanted arteries were evaluated for drug content (n = 3/time point) by LC-MS/MS and for drug and target protein (mTOR) distributions by immunofluorescence (IF, n = 6/time point).

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Sex-related differences have been noted in cardiovascular anatomy, pathophysiology, and treatment responses, yet we continued to drive evaluation of vascular device development in animal models without consideration of animal sex. We aimed to understand sex-related differences in the vascular responses to stent implantation by analyzing the pooled data of endovascular interventions in 164 Yucatan mini-swine (87 female, 77 male). Bare metal stents (BMS) or drug-eluting stents (DES) were implanted in 212 coronary arteries (63 single BMS implantation, 68 single DES implantation, 33 overlapped BMS implantation, and 48 overlapped DES implantation).

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Mycoplasmas are bacterial pathogens of a range of animals, including humans, and are a common cause of respiratory disease. However, the host genetic factors that affect resistance to infection or regulate the resulting pulmonary inflammation are not well defined. We and others have previously demonstrated that nonobese diabetic (NOD) mice can be used to investigate disease loci that affect bacterial infection and autoimmune diabetes.

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Mycoplasma bovis is an important pathogen of cattle, causing pneumonia, arthritis and otitis media in young calves, and mastitis in lactating cows, resulting in increased morbidity and, in some instances, mortality. The objective of this study was to evaluate the survival of a M. bovis isolate following nebulisation and to establish whether respiratory disease similar to that seen in the field could be induced in calves by exposing them to an aerosolised culture of M.

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