Publications by authors named "Robyn Richardson"

Background: To improve β-lactam delabeling outcomes, we need to understand current practice and the evidence base regarding its outcomes, safety, and impact.

Objectives: We sought to assess the existing published evidence reporting on the effectiveness of penicillin allergy testing and delabeling.

Methods: We conducted a systematic review of studies reporting β-lactam delabeling practices and outcomes after testing, including β-lactam use and patient understanding of the delabeling result.

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Background: Anaphylaxis is a severe, potentially fatal, systemic allergic reaction. Understanding predictors of recurrent and severe anaphylaxis in adults, and identifying gaps in ongoing anaphylaxis care, is needed to minimise its impact.

Aims: To evaluate the risk factors in adults with severe and recurrent anaphylaxis presentations and to evaluate the management of patients in regard to the recommended cascade of care.

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Background: Historical penicillin allergy is commonly reported, but the lack of standardized allergy clinic practices may diminish the ability to delabel beta-lactam allergy appropriately.

Objective: We sought to improve beta-lactam allergy testing and patient understanding of their antibiotic allergy status by standardizing testing and communication practices between 7 adult and pediatric hospital centers.

Methods: Phase 1 prospectively described the beta-lactam allergy testing practices at each center.

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c-Met is a well-characterized oncogene that is associated with poor prognosis in many solid tumor types. While responses to c-Met inhibitors have been observed in clinical trials, activity appears to be limited to those with MET gene amplifications or mutations. We developed a c-Met targeted antibody-drug conjugate (ADC) with preclinical activity in the absence of MET gene amplification or mutation, and activity even in the context of moderate protein expression.

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: Integrase strand transfer inhibitor-based antiretroviral therapy can cause weight gain. It is unknown if this is a class effect, with limited data regarding raltegravir. In 37 virologically suppressed adults (36 men, mean age 49 years) who switched from tenofovir disoproxil fumarate to raltegravir 400 mg twice daily, mean weight changes from baseline at weeks 24, 48 and 96 were not significant (maximum 0.

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Unlabelled: Background A substantial minority of patients living with HIV refuse or cease antiretroviral therapy (ART), have virological failure (VF) or develop an AIDS-defining condition (ADC) or serious non-AIDS event (SNAE). It is not understood which socioeconomic and psychosocial factors may be associated with these poor outcomes.

Methods: Thirty-nine patients with poor HIV treatment outcomes, defined as those who refused or ceased ART, had VF or were hospitalised with an ADC or SNAE (cases), were compared with 120 controls on suppressive ART.

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Zoledronic acid (ZOL) 5 mg annually was more effective than tenofovir disoproxil fumarate (TDF) switching at increasing bone mineral density (BMD) over 24 months in HIV-infected, osteopenic adults. To determine whether the effects of ZOL would persist without further infusions, we compared changes in left hip and spine BMD over 36 months in participants randomized to ZOL 5 mg at baseline and month 12 (and to continue TDF) or to switch TDF (without receiving ZOL). We also compared changes in the plasma bone turnover markers (BTMs) C-terminal telopeptide of type 1 collagen (CTX; bone resorption), and procollagen type 1 N propeptide (P1NP; bone formation) and determined whether CTX and P1NP changes at month 3 predicted BMD changes at month 36.

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Background: We updated a prior systematic review of initial antiretroviral therapy (ART) efficacy through week 144.

Materials And Methods: Studies (1994 to July 2017) were drawn from PubMed, ClinicalTrials.gov, Cochrane Library, and major conferences; design, eligibility, patient, and ART data were abstracted.

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Objective: To compare the effects of switching tenofovir disoproxil fumarate (TDF) or treatment with an intravenous bisphosphonate on bone mineral density (BMD) in HIV-positive adults with low bone mass.

Design: Two-year, randomized, open-label study at 10 sites in Australia and Spain.

Participants: Of 112 adults on TDF-based antiretroviral therapy (ART) screened, 87 with low BMD (T-score < -1.

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Despite the success of current biological therapeutics for rheumatoid arthritis, these therapies, targeting individual cytokines or pathways, produce beneficial responses in only about half of patients. Therefore, better therapeutics are needed. IL-6 and IL-17A are proinflammatory cytokines in many autoimmune and inflammatory diseases, and several therapeutics have been developed to specifically inhibit them.

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Objectives: Completion rates for HIV postexposure prophylaxis (PEP) are often low. We investigated the adherence and safety of dolutegravir (DTG; 50 mg daily) with tenofovir disoproxil fumarate-emtricitabine (TDF-FTC; 300/200 mg, respectively) as three-drug PEP in gay and bisexual men.

Design: Open-label, single-arm study at three sexual health clinics and two emergency departments in Australia.

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The proteasome, a validated cellular target for cancer, is central for maintaining cellular homeostasis, while fatty acid synthase (FAS), a novel target for numerous cancers, is responsible for palmitic acid biosynthesis. Perturbation of either enzymatic machine results in decreased proliferation and ultimately cellular apoptosis. Based on structural similarities, we hypothesized that hybrid molecules of belactosin C, a known proteasome inhibitor, and orlistat, a known inhibitor of the thioesterase domain of FAS, could inhibit both enzymes.

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Background: Completion rates for human immunodeficiency virus (HIV) postexposure prophylaxis (PEP) are low. We investigated the adherence and safety of coformulated emtricitabine (FTC), rilpivirine (RPV), and tenofovir disoproxil fumarate (TDF) as a 3-drug, single-tablet regimen for PEP in men who have sex with men (MSM).

Methods: In an open-label, single-arm study at 2 public sexual health clinics and 2 hospital emergency departments in urban Australia, 100 HIV-uninfected MSM requiring 3-drug PEP received single-tablet FTC-RPV-TDF once daily for 28 days.

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3-dimensional (3D) culture models have the potential to bridge the gap between monolayer cell culture and in vivo studies. To benefit anti-cancer drug discovery from 3D models, new techniques are needed that enable their use in high-throughput (HT) screening amenable formats. We have established miniaturized 3D culture methods robust enough for automated HT screens.

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Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is potentially a very important therapeutic as it shows selectivity for inducing apoptosis in cancer cells whilst normal cells are refractory. TRAIL binding to its cognate receptors, Death Receptors-4 and -5, leads to recruitment of caspase-8 and classical activation of downstream effector caspases, leading to apoptosis. As with many drugs however, TRAIL's usefulness is limited by resistance, either innate or acquired.

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Abacavir's effect on cardiovascular function has not been studied prospectively. We measured augmentation index (a measure of arterial stiffness) in 20 men who switched from abacavir to tenofovir. After 4 weeks, mean augmentation index reduced from 22% by 4% (P = 0.

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Objective: Protease inhibitor therapy is associated with an increased risk of myocardial infarction. Half this risk appears attributable to fasting dyslipidemia, but half remains unexplained. We compared the fasting and postprandial effects of low-dose ritonavir and raltegravir on cardiovascular and metabolic risk factors.

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Fatty acid synthase (FAS) is necessary for growth and survival of tumor cells and is a promising drug target for oncology. Here, we report on the syntheses and activity of novel inhibitors of the thioesterase domain of FAS. Using the structure of orlistat as a starting point, which contains a beta-lactone as the central pharmacophore, 28 novel congeners were synthesized and examined.

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Beta-lactam derivatives of orlistat were prepared and their inhibitory activities toward the thioesterase domain of fatty acid synthase (FAS-TE) were evaluated using a recombinant form of the enzyme. While in general these derivatives showed lower potency compared to beta-lactones, a reasonably potent, lead compound (-)-9 (IC(50)=8.6microM) was discovered that suggests that this class of compounds should be evaluated further.

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Fatty acid synthase (FAS) is up-regulated in a wide range of cancers and has been recently identified as a potential therapeutic target. Indeed, previous research has shown that inhibition of FAS with active site-modifying agents can block tumor cell proliferation, elicit tumor cell death, and prevent tumor growth in animal models. Here, we use a high-throughput fluorogenic screen and identify a novel pharmacophore, 5-(furan-2-ylmethylene) pyrimidine-2,4,6-trione, which inhibits the thioesterase domain of FAS.

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Concise syntheses of orlistat (Xenical), a two-carbon transposed orlistat derivative, and valilactone are described that employ the tandem Mukaiyama aldol-lactonization (TMAL) process as a key step. This process allows facile modification of the alpha-side chain. Versatile strategies for modifying the delta-side chain are described, involving cuprate addition and olefin metathesis.

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The recent finding that the FDA-approved antiobesity agent orlistat (tetrahydrolipstatin, Xenical) is a potent inhibitor of the thioesterase domain of fatty acid synthase (FAS) led us to develop a concise and practical asymmetric route to pseudosymmetric 3,4-dialkyl-cis-beta-lactones. The well-documented up-regulation of FAS in cancer cells makes this enzyme complex an interesting therapeutic target for cancer. The described route to 3,4-dialkyl-beta-lactones is based on a two-step process involving Calter's catalytic, asymmetric ketene dimerization of acid chlorides followed by a facial-selective hydrogenation leading to cis-substituted-beta-lactones.

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[reaction: see text] Lysophospholipase D (lysoPLD), also known as autotaxin (ATX), is an important source of the potent mitogen lysophosphatidic acid (LPA). Two fluorogenic substrate analogues for lysoPLD were synthesized in nine steps from (S)-PMB-glycerol. The substrates (FS-2 and FS-3) show significant increases in fluorescence when treated with recombinant ATX and have potential applications in screening for this emerging drug target.

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