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PURPOSE: Investigate risk factors for short term reactivation of retinopathy of prematurity (ROP) after intravitreal ranibizumab (IVR) therapy and determine safety and efficacy of repeat injections. METHODS: Retrospective chart review study of patients screened for ROP as inpatients between 2013-2023 who received IVR within the UCLA healthcare system. Primary outcomes were rates and timing of short term ROP reactivation, defined as repeat worsening of ROP to stage 2 or 3 before 52 weeks postmenstrual age (PMA), as well as risk factors for reactivation. Other outcomes included adverse events and rates of reactivation after a second intravitreal injection. RESULTS: 82 eyes of 43 patients received primary IVR 0.25mg/0.025cc for type 1 ROP. 13 patients (22 eyes) (30.2% of patients, 26.8% of eyes) developed short term reactivation an average of 7.2±1.7 weeks after treatment. Increased reactivation risk was associated with zone I disease (OR 6.23, 95% CI 1.35-28.7, p=0.019), lower PMA at 1st injection (OR 1.64, 95% CI 1.19-2.26; p=0.003), and lower gestational age at birth (OR 1.80, 95% CI 1.04-3.13, p=0.037). Of the 13 patients that received repeat injections, 5 required laser treatment for a second reactivation (11.6% of patients receiving IVR). No eyes developed retinal vascular occlusion, endophthalmitis or cataract. CONCLUSION: Repeat injections may be required after primary IVR for aggressive ROP. Repeat IVR treatment for ROP is effective and poses few ophthalmic adverse events, though additional reactivation remains a risk.
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PURPOSE: To report eight cases of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) or persistent placoid maculopathy (PPM) initially masquerading as age-related macular degeneration (AMD) in elderly individuals. METHODS: APMPPE or PPM eyes in patients above age 55 years with macular RPE disruption including drusenoid lesions on macular examination and/or with multimodal imaging were included. At least one method of multimodal imaging including fluorescein angiography (FA), indocyanine green angiography (ICGA), optical coherence tomography (OCT) and OCT angiography (OCTA) was performed in all eyes for diagnosis and to monitor for macular neovascularization (MNV). RESULTS: Eight elderly male patients presented with vision loss and were all initially diagnosed with non-neovascular or neovascular AMD. With the aid of multimodal retinal imaging, a final diagnosis of either APMPPE or PPM was rendered. With FA and ICGA, choroidal hypoperfusion was detected in all but one eye. With OCT, the angular sign of Henle fiber layer hyperreflectivity (ASHH) was identified in >50% of eyes. With OCTA, inner choroidal flow deficits were detected in all eyes. MNV requiring anti-VEGF injection therapy complicated 3 of 8 cases. CONCLUSIONS: Both APMPPE and PPM may develop in elderly individuals and may masquerade as AMD on presentation. Multimodal imaging including FA, ICGA, and OCTA are important diagnostic modalities to assess for inner choroidal hypoperfusion to arrive at an accurate diagnosis, and to detect MNV which frequently complicates APMPPE and PPM. In these patients, serial anti-VEGF intravitreal injections are essential in treating MNV and in preventing significant vision loss.
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BACKGROUND: Chronic back and knee pain impairs health-ârelated quality of life (HRQoL) and patient enablement can improve HRQoL. AIM: To determine whether enablement was a moderator of the effect of chronic back and knee pain on HRQoL. DESIGN AND SETTING: A cross-sectional study of Chinese patients with chronic back and knee problems in public primary care clinics in Hong Kong. METHOD: Each participant completed the Chinese Patient Enablement Instrument-2 (PEI-2), the Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Pain Rating Scale (PRS). Multivariable regression examined the effects of PRS score and PEI-2 score on WOMAC total score. A moderation regression model and simple slope analysis were used to evaluate whether the interaction between enablement (PEI-2) and pain (PRS) had a significant effect on HRQoL (WOMAC). RESULTS: Valid patient-reported outcome data from 1306 participants were analysed. PRS score was associated with WOMAC total score (ß = 0.326, P<0.001), whereas PEI-2 score was associated inversely with WOMAC total score (ß = -0.260, P<0.001) and PRS score. The effect of the interaction between PRS and PEI-2 (PRS × PEI-2) scores on WOMAC total score was significant (ß = -0.191, P<0.001) suggesting PEI-2 was a moderator. Simple slope analyses showed that the relationship between PRS and WOMAC was stronger for participants with a low level of PEI-2 (gradient 3.056) than for those with a high level of PEI-2 (gradient 1.746). CONCLUSION: Patient enablement moderated the impact of pain on HRQoL. A higher level of enablement can lessen impairment in HRQoL associated with chronic back and knee pain.
Subject(s)
Osteoarthritis, Knee , Quality of Life , Humans , Cross-Sectional Studies , Osteoarthritis, Knee/complications , Pain , Primary Health CareABSTRACT
In this paper we describe the analysis, planning, design, development, implementation and evaluation of a new online Graduate Certificate in Genomic Counselling and Variant Interpretation (GCGCVI) at The University of British Columbia (UBC). Genetic counselling is now a prerequisite for diagnostic genomic testing in many countries, demanding that genetic counselling practitioners have up-to-the-moment genomic counselling skills and knowledge. Current practitioners reported a desire for more training in this rapidly developing field: our international survey revealed substantial interest in online continuing education addressing themes such as testing and clinical bioinformatics, applied variant interpretation, evidence-based genomic counselling, and other emerging genomic topics. However, our market analysis found no post-graduate program globally that offered such training. To fill this gap, our oversight team of genetic counsellors and geneticists therefore guided development of curriculum and materials, and online learning specialists developed rigorous interactive asynchronous online graduate courses through collaboration with subject matter experts, following best practices in online learning design. Since launch in September 2020, we have gathered learner feedback using surveys and focus groups, and we have used learning analytics to understand how learners engaged with each other and with course materials. Together, these have helped us understand learner behaviour and guide the continuous process of design improvement to support the learning goals of this audience of professional learners. Our courses have been reviewed and approved by the UBC Faculty of Medicine, UBC Senate, and the Province of British Columbia Ministries of Advanced Education and Health, and assessed by the National Society of Genetic Counselors (NSGC, USA) and the Canadian Association of Genetic Counsellors (CAGC) to enable learners to receive North American continuing education credits. To date, 151 individuals from 18 countries have succeeded in one or more course and 43 have completed the entire certificate.
Subject(s)
Curriculum , Learning , Humans , Genomics , British Columbia , CounselingABSTRACT
PURPOSE: To determine the effect of resident- vs attending-led surgeries on patient outcomes in ophthalmic surgery. DESIGN: Systematic review and meta-analysis. METHODS: Two independent authors searched PubMed, EMBASE, and Cochrane Library from inception to March 2022. Categorical data from studies were pooled to report odds ratio (OR) and 95% CIs. Continuous data were analyzed to yield standardized mean difference (SMD) and 95% CIs. Propensity-matched studies were analyzed separately. Study quality was assessed using the Newcastle-Ottawa Scale. RESULTS: Twenty-four studies were included in this meta-analysis. Seventeen of the 20 outcomes had no significant differences between the 2 cohorts. Notably, many critical cataract surgery-related outcomes showed no significant differences, including posterior capsular tear, lens fragment retainment, and retinal detachment. Among propensity-scored studies, the resident-led surgeries had longer operative duration (SMD 0.81, 95% CI 0.29, 1.33; 3 studies [260 patients], I2 = 74%) and had an increased risk of an unplanned return to the operating room (OR 2.58, 95% CI 1.31, 5.06; 4 studies [342 patients], I2 = 0%). Among 2 non-propensity-scored, resident-led surgeries had increased incidence of choroidal detachment or choroidal effusion (OR 2.28, 95% 1.02, 5.09; 2 studies [401 patients], I2 = 19%). No significant difference was found for ocular hypotony. Significant heterogeneity existed among propensity-scored studies. CONCLUSIONS: Resident-led surgeries appear overall safe, effective, and comparable to attending-led surgeries with respect to commonly encountered perioperative complications. Specific differences in outcomes exhibit significant heterogeneity and small sample sizes, and may be of unclear or equivocal clinical significance.
Subject(s)
Cataract Extraction , Postoperative Complications , Humans , Postoperative Complications/epidemiology , Cataract Extraction/adverse effectsABSTRACT
BACKGROUND: Information on HRQOL can enhance patient diagnosis and management but it is rarely available in routine clinical practice. This mixed-method study evaluated the feasibility and acceptability of the electronic EQ-5D-5L measurement of HRQOL in patients with chronic musculoskeletal problems in primary care. METHODS: In three primary care clinics, 665 patients with musculoskeletal problems completed the electronic EQ-5D-5L and Visual Analogue Scale (e-EQ-5D-5L/VAS), and a questionnaire on socio-demographics, perceived ease of use (PEOU), and perceived usefulness (PU) at baseline and two follow-ups. Patient completion and response rates, and time to complete the e-EQ-5D-5L/VAS were measured. During the same consultations, 49 doctors reviewed the e-EQ-5D-5L/VAS reports and completed a clinician questionnaire on PEOU, PU, and time spent to address each report. Individual interviews along with focus group discussions were conducted on patients, doctors, and research assistants for further exploration. RESULTS: Mean completion time reduced from baseline to first and second follow-up (120.66, 83.99, and 105.22 s, respectively). Completion and response rates were high at each follow-up visit (> 99.8% and > 91.11%, respectively). Doctors needed less than 2 min to read the report but felt the time required to address the report was a significant barrier. Some patients had difficulties using e-platforms, in understanding or answering questions; but, PEOU improved with time (p < 0.001). Most patients found the e-platforms useful (> 85.3%). Clinicians agreed a great majority of the reports were easy to use (76.0-85.1%) and useful (69.2-72.0%), particularly aiding with a holistic view of the patient's musculoskeletal problem. CONCLUSION: The e-EQ-5D-5L/VAS is a feasible and acceptable measurement of HRQOL of patients with chronic musculoskeletal problems in routine primary care in Hong Kong which can assist real-time management decisions. TRIAL REGISTRATION: NCT03609762.
Subject(s)
Electronics , Quality of Life , Feasibility Studies , Hong Kong , Humans , Primary Health Care , Psychometrics/methodsABSTRACT
This study quantitatively examines whether health literacy can reduce belief in COVID-19 misinformation and conspiracy theories. Conducting path and cluster analyses on survey data collected from 1,488 adults in Japan in 2021, we found that while health literacy reduces people's belief about COVID-19 and vaccination misinformation, it has no direct effect on their belief in COVID-19 conspiracy theories. That said, the results also highlighted the importance of health literacy. It is found that even though high health literacy does not guarantee a low degree of conspiracy beliefs, low health literacy is associated with high susceptibility to both misinformation and conspiracy theories. Moreover, people who relied more on social media than mass media for COVID-19 news and reported on having been more severely affected by the pandemic were found to be more likely to have lower health literacy and higher belief in misinformation and conspiracy theories. Based on the findings, we discussed ways to enhance health literacy research and promotion in Japan.
Subject(s)
COVID-19 , Health Literacy , Adult , COVID-19/epidemiology , Humans , Infodemic , Japan/epidemiology , SARS-CoV-2ABSTRACT
The Food and Drug Administration has licensed, approved, and expanded guidelines for dozens of vaccines since 2010. Although advancements in biotechnology have made vaccines more effective and safer, none are completely free from adverse effects. Many vaccines have been implicated in causing ocular adverse events based on the temporal association of exposure and putative complication. Determination of causality is difficult. We provide an overview of vaccine side effects and also examine the English literature and the Vaccine Adverse Events Reporting System (VAERS) from 2010 through 2020 for vaccine-implicated ocular adverse events. While reactions of eyelids and conjunctiva are commonly reported, the most frequently implicated serious adverse events are optic neuritis and various patterns of intraocular inflammation. Live attenuated vaccines have the potential to cause ocular infection from vaccine-strain organisms, particularly in those immunosuppressed. While postmarketing registries for suspect vaccination adverse events, such as VAERS, are unable to determine causal associations, they are a mainstay in signaling suspected trends that require investigation. The majority of probable and possible serious ocular adverse effects are distinctly uncommon.
Subject(s)
Adverse Drug Reaction Reporting Systems , Drug-Related Side Effects and Adverse Reactions , Humans , United States , Vaccination/adverse effectsABSTRACT
The purpose of this project was to develop and implement an interprofessional informatics curriculum. We developed a digital health serious game at the centre of this curriculum where the focus was a team-based approach to learning technologies used in the healthcare setting. The overall satisfaction scores were moderately high after the game. Serious games can be engaging for health sciences students.
Subject(s)
Curriculum , Learning , Delivery of Health Care , Humans , Informatics , StudentsABSTRACT
Bacterial adhesion and the succeeding biofilm formation onto surfaces are responsible for implant- and device-associated infections. Bifunctional coatings integrating both nonfouling components and antimicrobial peptides (AMPs) are a promising approach to develop potent antibiofilm coatings. However, the current approaches and chemistry for such coatings are time-consuming and dependent on substrates and involve a multistep process. Also, the information is limited on the influence of the coating structure or its components on the antibiofilm activity of such AMP-based coatings. Here, we report a new strategy to rapidly assemble a stable, potent, and substrate-independent AMP-based antibiofilm coating in a nonfouling background. The coating structure allowed for the screening of AMPs in a relevant nonfouling background to identify optimal peptide combinations that work in cooperation to generate potent antibiofilm activity. The structure of the coating was changed by altering the organization of the hydrophilic polymer chains within the coatings. The coatings were thoroughly characterized using various surface analytical techniques and correlated with the efficiency to prevent biofilm formation against diverse bacteria. The coating method that allowed the conjugation of AMPs without altering the steric protection ability of hydrophilic polymer structure results in a bifunctional surface coating with excellent antibiofilm activity. In contrast, the conjugation of AMPs directly to the hydrophilic polymer chains resulted in a surface with poor antibiofilm activity and increased adhesion of bacteria. Using this coating approach, we further established a new screening method and identified a set of potent surface-tethered AMPs with high activity. The success of this new peptide screening and coating method is demonstrated using a clinically relevant mouse infection model to prevent catheter-associated urinary tract infection (CAUTI).
Subject(s)
Anti-Bacterial Agents/pharmacology , Antimicrobial Cationic Peptides/pharmacology , Biofouling/prevention & control , Coated Materials, Biocompatible/pharmacology , Immobilized Proteins/pharmacology , Acrylamides/chemistry , Animals , Anti-Bacterial Agents/chemical synthesis , Antimicrobial Cationic Peptides/chemical synthesis , Catheters/microbiology , Coated Materials, Biocompatible/chemical synthesis , Humans , Immobilized Proteins/chemical synthesis , Indoles/chemistry , Male , Mice, Inbred BALB C , Polymers/chemistry , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Staphylococcus saprophyticus/drug effects , Staphylococcus saprophyticus/physiology , Urinary Tract Infections/prevention & controlABSTRACT
BACKGROUND: Maintenance intravenous fluids (IVFs) are commonly used in the hospital setting. Hypotonic IVFs are commonly used in pediatrics despite concerns about high incidence of hyponatremia. We aimed to increase isotonic maintenance IVF use in children admitted from the emergency department (ED) from a baseline of 20% in 2018 to >80% by December 2019. METHODS: We included patients aged 28 days to 18 years receiving maintenance IVFs (rate >10 mL/hour) at the time of admission. Patients with active chronic medical problems were excluded. Interventions included institutional discussions on isotonic IVF based on literature review, education on isotonic IVF use per the American Academy of Pediatrics guideline (isotonic IVF use with appropriate potassium chloride and dextrose), electronic medical record changes to encourage isotonic IVF use, and group practice review with individual physician audit and feedback. Balancing measures were the frequency of serum electrolyte checks within 24 hours of ED admission and occurrence of hypernatremia. Data were analyzed by using statistical process control charts. RESULTS: Isotonic maintenance IVF use improved, with special cause observed twice; the 80% goal was met and sustained. No difference was noted in serum electrolyte checks within 24 hours of admission (P > .05). There was no increase in occurrence of hypernatremia among patients who received isotonic IVF compared with those who received hypotonic IVF (P > .05). CONCLUSIONS: The application of improvement methods resulted in improved isotonic IVF use in ED patients admitted to the inpatient setting. Institutional readiness for change at the time of the American Academy of Pediatrics guideline release and hardwiring of preferred fluids via electronic medical record changes were critical to success.
Subject(s)
Emergency Service, Hospital/organization & administration , Emergency Service, Hospital/standards , Fluid Therapy/methods , Isotonic Solutions/administration & dosage , Adolescent , Child , Child, Preschool , Electronic Health Records , Fluid Therapy/adverse effects , Guideline Adherence , Humans , Hyponatremia/prevention & control , Infant , Infant, Newborn , Infusions, Intravenous , Isotonic Solutions/adverse effects , Medical Staff, Hospital/education , Patient Care Team , Practice Guidelines as Topic , Quality Improvement , Tertiary Care Centers/organization & administration , Tertiary Care Centers/standards , United StatesABSTRACT
Catheter-associated urinary tract infections (CAUTIs) are one of the most commonly occurring hospital-acquired infections. Current coating strategies to prevent catheter-associated biofilm formation are limited by their poor long-term efficiency and limited applicability to diverse materials. Here, the authors report a highly effective non-fouling coating with long-term biofilm prevention activity and is applicable to diverse catheters. The thin coating is lubricous, stable, highly uniform, and shows broad spectrum prevention of biofilm formation of nine different bacterial strains and prevents the migration of bacteria on catheter surface. The coating method is adapted to human-sized catheters (both intraluminal and extraluminal) and demonstrates long-term biofilm prevention activity over 30 days in challenging conditions. The coated catheters are tested in a mouse CAUTI model and demonstrate high efficiency in preventing bacterial colonization of both Gram-positive and Gram-negative bacteria. Furthermore, the coated human-sized Foley catheters are evaluated in a porcine CAUTI model and show consistent efficiency in reducing biofilm formation by Escherichia coli (E. coli) over 95%. The simplicity of the coating method, the ability to apply this coating on diverse materials, and the high efficiency in preventing bacterial adhesion increase the potential of this method for the development of next generation infection resistant medical devices.
Subject(s)
Catheter-Related Infections , Animals , Anti-Bacterial Agents , Biofilms , Catheter-Related Infections/prevention & control , Escherichia coli , Gram-Negative Bacteria , Gram-Positive Bacteria , Mice , Swine , Urinary CathetersABSTRACT
The naturally occurring host defense peptide (HDP), aurein 2.2, secreted by the amphibian Litoria aurea, acts as a moderate antibacterial, affecting Gram positive bacteria such as Staphylococcus aureus by forming selective ion pores. In a quest to find more active analogues of aurein 2.2, peptides 73 and 77 were discovered. These peptides were rich in arginine and tryptophan and found to have MICs of 4 µg/mL. Here we examined what impact the increased charge from +2 to +3 and a slight increase in hydrophobic moment relative to aurein 2.2 had on the mechanism of action of these two analogues. Using a time-kill assay, both peptides 73 and 77 were found to kill bacteria more effectively than the parent peptide. Using solution CD and NMR, the peptides were found to not adopt a continuous α-helical structure, i.e. the analogues were not helical from residue 1-13 like the parent peptide. Results obtained from oriented CD (OCD), DiSC35 and pyranine assays and a gel retardation experiment showed that the peptides did not function by membrane perturbation and further showed that peptide 73 and 77 did not interact with DNA. Overall, the data were consistent with these peptides acting as cell penetrating peptides with intracellular targets, which did not appear to be DNA.
Subject(s)
Antimicrobial Cationic Peptides/chemistry , Amphibian Proteins/chemistry , Amphibians , Animals , Antimicrobial Cationic Peptides/pharmacology , Cell-Penetrating Peptides/chemistry , Drug Discovery , Gram-Positive Bacteria/drug effects , Protein Conformation , Structure-Activity RelationshipABSTRACT
PURPOSE: To determine factors predictive of anatomic, visual, and financial outcomes after traditional and nontraditional primary pneumatic retinopexy (PR) for rhegmatogenous retinal detachment (RD). DESIGN: Retrospective interventional case series and cost comparison. METHODS: Participants: Total of 178 eyes (156 patients) with PR-repaired primary RD by a single surgeon at a clinical practice from January 2001 to December 2013 and followed for ≥1 year. The cohort had 2 subgroups: traditional (TPR) and nontraditional (NTPR) PR. MAIN OUTCOME MEASURES: Characteristics associated with best-corrected visual acuity (BCVA) and anatomic outcomes. Cost analysis and potential cost savings comparing PR to scleral buckle and vitrectomy. RESULTS: One hundred thirty-one of 178 eyes (73.5%) were successfully treated at 1 year (postoperative year 1): 72.8% (75/103) in TPR and 74.6% (56/75) in NTPR. Macula-off detachment (-0.44 logMAR, P < .001) and clock hours of RD (-0.84 logMAR, P < .001) correlated with improved BCVA; pseudophakia (0.26 logMAR, P = .002) and inferior retinal tears (0.62 logMAR, P = .009) correlated with worsening BCVA. Pseudophakia (-0.15, P = .03), inferior quadrant RD (-0.27, P < .001), and proliferative vitreoretinopathy (-0.68, P < .001) correlated with anatomic failure. Total average cost for TPR and NTPR was $1248.37 ± $882.11 and $1471.91 ± $942.84, respectively (P = .10). PR had a potential cost savings of 62% and 60.8% when compared to scleral buckle and vitrectomy, respectively. CONCLUSIONS: PR results in successful anatomic and visual outcomes in both TPR and NTPR repair of primary RD. Preoperative pseudophakia is associated with worse visual outcomes and less anatomic success. The cost of primary PR and subsequent procedures to achieve final anatomic success was not significantly different between TPR and NTPR, and supports the possible cost-effectiveness of expanded indications for PR.
Subject(s)
Cryotherapy/economics , Health Care Costs , Laser Therapy/economics , Retinal Detachment/economics , Retinal Detachment/surgery , Visual Acuity/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Cost-Benefit Analysis , Cryotherapy/methods , Endotamponade , Female , Humans , Laser Therapy/methods , Male , Middle Aged , Retinal Detachment/physiopathology , Retrospective Studies , Scleral Buckling/economics , Sulfur Hexafluoride/administration & dosage , Treatment Outcome , Vitrectomy/economicsABSTRACT
Antimicrobial peptides have been the focus of considerable research; however, issues associated with toxicity and aggregation have the potential to limit clinical applications. Here, a derivative of a truncated version of aurein 2.2 (aurein 2.2Δ3), namely peptide 73, was investigated, along with its d-amino acid counterpart (D-73) and a retro-inverso version (RI-73). A version that incorporated a cysteine residue to the C-terminus (73c) was also generated, as this form is required to covalently attach antimicrobial peptides to polymers (e.g., polyethylene glycol (PEG) or hyperbranched polyglycerol (HPG)). The antimicrobial activity of the 73-derived peptides was enhanced 2- to 8-fold, and all the derivatives eradicated preformed Staphylococcus aureus biofilms. Formulation of the peptides with compatible polyethylene glycol (PEG)-modified phospholipid micelles alleviated toxicity toward human cells and reduced aggregation. When evaluated in vivo, the unformulated d-enantiomers aggregated when injected under the skin of mice, but micelle encapsulated peptides were well absorbed. Pegylated micelle formulated peptides were investigated for their potential as therapeutic agents for treating high-density infections in a murine cutaneous abscess model. Formulated peptide 73 reduced abscess size by 36% and bacterial loads by 2.2-fold compared to the parent peptide aurein 2.2Δ3. Micelle encapsulated peptides 73c and D-73 exhibited superior activity, further reducing abscess sizes by 85% and 63% and lowering bacterial loads by 510- and 9-fold compared to peptide 73.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/chemistry , Antimicrobial Cationic Peptides/administration & dosage , Antimicrobial Cationic Peptides/chemistry , Methicillin-Resistant Staphylococcus aureus/drug effects , Staphylococcal Skin Infections/drug therapy , Animals , Drug Compounding , Female , Humans , Methicillin-Resistant Staphylococcus aureus/physiology , Mice , Micelles , Microbial Sensitivity Tests , Phospholipids/chemistry , Polyethylene Glycols/chemistry , Staphylococcal Skin Infections/microbiologyABSTRACT
Biofilms are multicellular communities of bacteria that can adhere to virtually any surface. Bacterial biofilms are clinically relevant, as they are responsible for up to two-thirds of hospital acquired infections and contribute to chronic infections. Troublingly, the bacteria within a biofilm are adaptively resistant to antibiotic treatment and it can take up to 1000 times more antibiotic to kill cells within a biofilm when compared to planktonic bacterial cells. Identifying and optimizing compounds that specifically target bacteria growing in biofilms is required to address this growing concern and the reported antibiofilm activity of natural and synthetic host defence peptides has garnered significant interest. However, a standardized assay to assess the activity of antibiofilm agents has not been established. In the present work, we describe two simple assays that can assess the inhibitory and eradication capacities of peptides towards biofilms that are formed by both Gram-positive and negative bacteria. These assays are suitable for high-throughput workflows in 96-well microplates and they use crystal violet staining to quantify adhered biofilm biomass as well as tetrazolium chloride dye to evaluate the metabolic activity of the biofilms. The effect of media composition on the readouts of these biofilm detection methods was assessed against two strains of Pseudomonas aeruginosa (PAO1 and PA14), as well as a methicillin resistant strain of Staphylococcus aureus. Our results demonstrate that media composition dramatically alters the staining patterns that were obtained with these dye-based methods, highlighting the importance of establishing appropriate biofilm growth conditions for each bacterial species to be evaluated. Confocal microscopy imaging of P. aeruginosa biofilms grown in flow cells revealed that this is likely due to altered biofilm architecture under specific growth conditions. The antibiofilm activity of several antibiotics and synthetic peptides were then evaluated under both inhibition and eradication conditions to illustrate the type of data that can be obtained using this experimental setup.
Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Defensins/pharmacology , Microbial Sensitivity Tests/methods , Microbial Sensitivity Tests/standards , Oligopeptides/pharmacology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Staphylococcus aureus/drug effects , Staphylococcus aureus/physiologyABSTRACT
This study evaluated the short-term effects of tofacitinib treatment on peripheral blood leukocyte phenotype and function, and the reversibility of any such effects following treatment withdrawal in healthy volunteers. Cytomegalovirus (CMV)-seropositive subjects received oral tofacitinib 10â¯mg twice daily for 4â¯weeks and were followed for 4â¯weeks after drug withdrawal. There were slight increases in total lymphocyte and total T-cell counts during tofacitinib treatment, and B-cell counts increased by up to 26%. There were no significant changes in granulocyte or monocyte counts, or granulocyte function. Naïve and central memory T-cell counts increased during treatment, while all subsets of activated T cells were decreased by up to 69%. T-cell subsets other than effector memory cluster of differentiation (CD)4+, activated naïve CD4+ and effector CD8+ T-cell counts and B-cell counts, normalized 4â¯weeks after withdrawal. Following ex vivo activation, measures of CMV-specific T-cell responses, and antigen non-specific T-cell-mediated cytotoxicity and interferon (IFN)-γ production, decreased slightly. These T-cell functional changes were most pronounced at Day 15, partially normalized while still on tofacitinib and returned to baseline after drug withdrawal. Total natural killer (NK)-cell counts decreased by 33%, returning towards baseline after drug withdrawal. NK-cell function decreased during tofacitinib treatment, but without a consistent time course across measured parameters. However, markers of NK-cell-mediated cytotoxicity, antibody-dependent cellular cytotoxicity and IFN-γ production were decreased up to 42% 1â¯month after drug withdrawal. CMV DNA was not detectable in whole blood, and there were no cases of herpes zoster reactivation. No new safety concerns arose. In conclusion, the effect of short-term tofacitinib treatment on leukocyte composition and function in healthy CMV+ volunteers is modest and largely reversible 4â¯weeks after withdrawal.
Subject(s)
Janus Kinase Inhibitors/pharmacology , Leukocytes/drug effects , Piperidines/pharmacology , Pyrimidines/pharmacology , Pyrroles/pharmacology , Adult , Aged , Arthritis, Rheumatoid/drug therapy , Female , Healthy Volunteers , Humans , Leukocytes/immunology , Lymphocyte Count , Male , Middle Aged , Phenotype , Piperidines/adverse effects , Pyrimidines/adverse effects , Pyrroles/adverse effects , T-Lymphocytes/drug effects , T-Lymphocytes/immunologyABSTRACT
OBJECTIVE: This phase II, randomised, double-blind, placebo-controlled clinical trial was designed to evaluate the efficacy and safety of PF-00547659, a fully human monoclonal antibody that binds to human mucosal addressin cell adhesion molecule (MAdCAM) to selectively reduce lymphocyte homing to the intestinal tract, in patients with moderate-to-severe Crohn's disease (CD). DESIGN: Eligible adults were aged 18-75 years, with active moderate-to-severe CD (Crohn's Disease Activity Index (CDAI) 220-450), a history of failure or intolerance to antitumour necrosis factor and/or immunosuppressive agents, high-sensitivity C reactive protein >3.0 mg/L and ulcers on colonoscopy. Patients were randomised to PF-00547659 22.5 mg, 75 mg or 225 mg or placebo. The primary endpoint was CDAI 70-point decrease from baseline (CDAI-70) at week 8 or 12. RESULTS: In all, 265 patients were eligible for study entry. Although CDAI-70 response was not significantly different with placebo versus PF-00547659 treatment at weeks 8 or 12, remission rate was greater in patients with higher baseline C reactive protein (>5 mg/L vs >18.8 mg/L, respectively). Soluble MAdCAM decreased significantly from baseline to week 2 in a dose-related manner and remained low during the study in PF-00547659-treated patients. Circulating ß7+ CD4+ central memory T-lymphocytes increased at weeks 8 and 12 with PF-00547659 treatment. No safety signal was seen. CONCLUSIONS: Clinical endpoint differences between PF-00547659 and placebo did not reach statistical significance in patients with moderate-to-severe CD. PF-00547659 was pharmacologically active, as shown by a sustained dose-related decrease in soluble MAdCAM and a dose-related increase in circulating ß7+ central memory T cells. TRIAL REGISTRATION NUMBER: NCT01276509; Results.
Subject(s)
Antibodies, Monoclonal, Humanized , Crohn Disease , Adult , Aged , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , C-Reactive Protein/analysis , Colonoscopy/methods , Crohn Disease/diagnosis , Crohn Disease/drug therapy , Crohn Disease/metabolism , Dose-Response Relationship, Drug , Double-Blind Method , Drug Monitoring/methods , Female , Gastrointestinal Agents/administration & dosage , Gastrointestinal Agents/adverse effects , Humans , Male , Middle Aged , Patient Acuity , Severity of Illness Index , Treatment OutcomeABSTRACT
BACKGROUND AND AIMS: Progressive multifocal leukoencephalopathy [PML], a brain infection associated with anti-integrin drugs that inhibit lymphocyte translocation from bloodstream to tissue, can be fatal. Decreased central nervous system [CNS] immune surveillance leading to this infection has been reported in patients with multiple sclerosis or Crohn's disease treated with anti-integrin antibody natalizumab. PF-00547659 is an investigational human monoclonal antibody for inflammatory bowel disease, targeted against α4ß7-mucosal addressin cell-adhesion molecule-1 [the integrin ligand selectively expressed in the gut]. We hypothesised that this selective agent would not affect central nervous system immune surveillance. METHODS: Cerebrospinal fluid from five healthy volunteers, and from 10 patients with Crohn's disease previously treated with immunosuppressants, was evaluated to assess the feasibility of the study. Subsequently, 39 patients with active Crohn's disease and previous immunosuppression were evaluated over 12 weeks of PF-00547659-induction therapy. We measured total lymphocytes, T cell subsets in cerebrospinal fluid, and circulating ß7+ memory cells. Disease activity was assessed using the Harvey-Bradshaw Index. RESULTS: Patients treated with PF-00547659 had no reduction of cerebrospinal fluid lymphocytes, T-lymphocyte subsets, or CD4:CD8 ratio, whereas circulating ß7+ memory cells increased significantly. A total of 28/35 [80%] patients had a clinical response and 27/34 [79%] had disease remission. Treatment-related adverse events, none serious, were reported in 23/49 [47%] patients. CONCLUSIONS: In patients with active Crohn's disease, natalizumab therapy increases the risk for PML, and the increased risk is thought to be associated with iatrogenic leukopenia within the CNS. PML under PF-00547659 may be a lesser concern, as this agent did not reduce lymphocytes or T cell subsets in the cerebrospinal fluid.