Pharmacological inhibition of CLK2 activates YAP by promoting alternative splicing of AMOTL2

Yes-associated protein (YAP), the downstream effector of the evolutionarily conserved Hippo pathway, promotes cellular proliferation and coordinates certain regenerative responses in mammals. Small molecule activators of YAP may, therefore, display therapeutic utility in treating disease states involving insufficient proliferative repair. From a high-throughput chemical screen of the comprehensive drug repurposing library ReFRAME, here we report the identification of SM04690, a clinical stage inhibitor of CLK2, as a potent activator of YAP-driven transcriptional activity in cells. CLK2 inhibition promotes alternative splicing of the Hippo pathway protein AMOTL2, producing an exon-skipped gene product that can no longer associate with membrane-bound proteins, resulting in decreased phosphorylation and membrane localization of YAP. This study reveals a novel mechanism by which pharmacological perturbation of alternative splicing inactivates the Hippo pathway and promotes YAP-dependent cellular growth.

Links Between Childhood Abuse, Insidious Trauma, and Methamphetamine Use Across the Lifespan Among Gay, Bisexual, and Other Men Who Have Sex with Men: A Qualitative Analysis

Developmental and lifespan examinations of methamphetamine use among gay, bisexual, and other men who have sex with men (GBM) remain limited. We used a feminist trauma framework to examine potential links between childhood trauma, trauma-related stressors, and methamphetamine use among GBM. From June 2018 to October 2018, semi-structured interviews (N = 33) were conducted with GBM across British Columbia. Interviews focused on sexual experiences, support services, and methamphetamine use. Using thematic analysis, two overarching trauma-related themes were identified: developmental and insidious trauma and coping with trauma-related stressors. GBM's methamphetamine use co-occurred with childhood experiences of family- and peer-perpetrated heterosexism, childhood sexual abuse, and intersecting forms of oppression/marginalization. These experiences manifested as internalized shame, interpersonal anxiety, and low self-esteem. In adulthood, participants reported difficulty managing emotions, low self-confidence, and loneliness. GBM reported using methamphetamine to manage negative emotions, life stressors, and overcome barriers to interpersonal connection. Findings indicate a need for trauma-informed interventions that address underlying issues and help GBM cultivate supportive relationships.

A covalent inhibitor of the YAP-TEAD transcriptional complex identified by high-throughput screening

Yes-associated protein (YAP), the master transcriptional effector downstream of the Hippo pathway, regulates essential cell growth and regenerative processes in animals. However, the activation of YAP observed in cancers drives cellular proliferation, metastasis, chemoresistance, and immune suppression, making it of key interest in developing precision therapeutics for oncology. As such, pharmacological inhibition of YAP by targeting its essential co-regulators, TEA domain transcription factors (TEADs) would likely promote tumor clearance in sensitive tumor types. From a fluorescence polarization-based high throughput screen of over 800 000 diverse small molecules, here we report the identification of a pyrazolopyrimidine-based scaffold that inhibits association of YAP and TEADs. Medicinal chemistry-based optimization identified mCMY020, a potent, covalent inhibitor of TEAD transcriptional activity that occupies a conserved, central palmitoylation site on TEADs.

Pharmacological inhibition of CLK2 activates YAP by promoting alternative splicing of AMOTL2

Yes-associated protein (YAP), the downstream effector of the evolutionarily conserved Hippo pathway, promotes cellular proliferation and coordinates certain regenerative responses in mammals. Small molecule activators of YAP may therefore display therapeutic utility in treating disease states involving insufficient proliferative repair. From a high-throughput chemical screen of the comprehensive drug repurposing library ReFRAME, here we report the identification of SM04690, a clinical stage inhibitor of CLK2, as a potent activator of YAP driven transcriptional activity in cells. CLK2 inhibition promotes alternative splicing of the Hippo pathway protein AMOTL2, producing an exon-skipped gene product that can no longer associate with membrane-bound proteins, resulting in decreased phosphorylation and membrane localization of YAP. This study reveals a novel mechanism by which pharmacological perturbation of alternative splicing inactivates the Hippo pathway and promotes YAP dependent cellular growth.

Multidrug-Resistant Shigella sonnei Bacteremia among Persons Experiencing Homelessness, Vancouver, British Columbia, Canada

Increased invasive bloodstream infections caused by multidrug resistant Shigella sonnei were noted in Vancouver, British Columbia, Canada, during 2021-2023. Whole-genome sequencing revealed clonal transmission of genotype 3.6.1.1.2 (CipR.MSM5) among persons experiencing homelessness. Improvements in identifying Shigella species, expanding treatment options for multidrug resistant infections, and developing public health partnerships are needed.

High throughput screening for drugs that inhibit 3C-like protease in SARS-CoV-2

The SARS coronavirus 2 (SARS-CoV-2) pandemic remains a major problem in many parts of the world and infection rates remain at extremely high levels. This high prevalence drives the continued emergence of new variants, and possibly ones that are more vaccine-resistant and that can drive infections even in highly vaccinated populations. The high rate of variant evolution makes clear the need for new therapeutics that can be clinically applied to minimize or eliminate the effects of COVID-19. With a hurdle of 10 years, on average, for first in class small molecule therapeutics to achieve FDA approval, the fastest way to identify therapeutics is by drug repurposing. To this end, we developed a high throughput cell-based screen that incorporates the essential viral 3C-like protease and its peptide cleavage site into a luciferase complementation assay to evaluate the efficacy of known drugs encompassing approximately 15,000 clinical-stage or FDA-approved small molecules. Confirmed inhibitors were also tested to determine their cytotoxic properties. Medicinal chemistry efforts to optimize the hits identified Tranilast as a potential lead. Here, we report the rapid screening and identification of potentially relevant drugs that exhibit selective inhibition of the SARS-CoV-2 viral 3C-like protease.

Identification of potent small molecule inhibitors of SARS-CoV-2 entry

The severe acute respiratory syndrome coronavirus 2 responsible for COVID-19 remains a persistent threat to mankind, especially for the immunocompromised and elderly for which the vaccine may have limited effectiveness. Entry of SARS-CoV-2 requires a high affinity interaction of the viral spike protein with the cellular receptor angiotensin-converting enzyme 2. Novel mutations on the spike protein correlate with the high transmissibility of new variants of SARS-CoV-2, highlighting the need for small molecule inhibitors of virus entry into target cells. We report the identification of such inhibitors through a robust high-throughput screen testing 15,000 small molecules from unique libraries. Several leads were validated in a suite of mechanistic assays, including whole cell SARS-CoV-2 infectivity assays. The main lead compound, calpeptin, was further characterized using SARS-CoV-1 and the novel SARS-CoV-2 variant entry assays, SARS-CoV-2 protease assays and molecular docking. This study reveals calpeptin as a potent and specific inhibitor of SARS-CoV-2 and some variants.

Bispecific repurposed medicines targeting the viral and immunological arms of COVID-19

Effective agents to treat coronavirus infection are urgently required, not only to treat COVID-19, but to prepare for future outbreaks. Repurposed anti-virals such as remdesivir and human anti-inflammatories such as barcitinib have received emergency approval but their overall benefits remain unclear. Vaccines are the most promising prospect for COVID-19, but will need to be redeveloped for any future coronavirus outbreak. Protecting against future outbreaks requires the identification of targets that are conserved between coronavirus strains and amenable to drug discovery. Two such targets are the main protease (Mpro) and the papain-like protease (PLpro) which are essential for the coronavirus replication cycle. We describe the discovery of two non-antiviral therapeutic agents, the caspase-1 inhibitor SDZ 224015 and Tarloxotinib that target Mpro and PLpro, respectively. These were identified through extensive experimental screens of the drug repurposing ReFRAME library of 12,000 therapeutic agents. The caspase-1 inhibitor SDZ 224015, was found to be a potent irreversible inhibitor of Mpro (IC50 30 nM) while Tarloxotinib, a clinical stage epidermal growth factor receptor inhibitor, is a sub micromolar inhibitor of PLpro (IC50 300 nM, Ki 200 nM) and is the first reported PLpro inhibitor with drug-like properties. SDZ 224015 and Tarloxotinib have both undergone safety evaluation in humans and hence are candidates for COVID-19 clinical evaluation.

Immunological and virological response to initial antiretroviral therapy among older people living with HIV in the Canadian Observational Cohort (CANOC)

OBJECTIVES

The aim of this study was to assess the adequacy of immunological recovery and virological suppression in response to antiretroviral therapy (ART) in the growing population of older people living with HIV (PLWH), as treatment regimens become more effective and tolerable.

METHODS

An interprovincial Canadian cohort of treatment-naïve PLWH who initiated ART after 1 January 2000 was used and age assessed in decades. Longitudinal absolute CD4 count response to treatment was modelled using generalized estimating equations. Cumulative incidence functions and proportional hazards models with a competing risk of death were used to estimate time to: (1) CD4 ≥ 200 cells/µL, (2) CD4 ≥ 500 cells/µL, (3) virological suppression (≤ 50 copies/mL), and (4) virological failure (> 200 copies/mL).

RESULTS

In all, 12 489 individuals starting ART between 2000 and 2016 with one or more post-treatment CD4 count or viral load were included in the analysis. Age > 60 years was associated with lower absolute CD4 recovery (adjusted β = -31 cells/µL) compared with age ≤ 30 years when pre-treatment CD4 count and other covariates were accounted for. Older age groups were less likely to achieve a CD4 ≥ 500 cells/µL, with the greatest effect in the > 60 group [adjusted hazard ratio (aHR) = 0.69, 95% confidence interval (CI): 0.57-0.84 vs. age ≤ 30). Older age groups were more likely to achieve viral suppression (age > 60, aHR = 1.20, 95% CI: 1.05-1.37) and less likely to have virological failure (age > 60, aHR = 0.46, 95% CI: 0.3-0.71) compared with those aged ≤ 30 years.

CONCLUSIONS

Older adults have robust virological responses to ART; however, individuals over the age 60 are more likely to experience blunted CD4 recovery.

The impact of cancer-related diarrhea on changes in cancer therapy patterns

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Background: We studied the impact that cancer related diarrhea (CRD) has on cancer therapy and treatment patterns, including persistence, discontinuation, adherence, and switching of chemotherapy and targeted therapies in patients with and without CRD. Methods: We performed a longitudinal observational study among adult ( > 18 yrs) patients with CRD identified by diagnosis codes or pharmacy claims compared to matched (1:1) non-CRD patients using claims data derived from the IQVIA PharMetrics Plus database. Index date was defined as the date of the first cancer claim, and we re-indexed patients based on CRD claims. Each patient had a 6-month pre-index period and a minimum 3-month follow-up post-index period. To adjust for selection bias and baseline differences, we directly matched the CRD patients to non-CRD patients. Treatment patterns were evaluated and stratified for the first cancer therapy with or without CRD (chemotherapy vs targeted therapy vs both targeted and chemotherapy). Discontinuation was defined as a 30-day gap for chemotherapy and a 14-day gap for targeted therapies from index therapy; switching was a new chemotherapy or targeted therapy prescription within 30 days following discontinuation of index therapy. We computed adherence as the proportion of days covered over the 12-month post-index period and persistence as mean number of days on index therapy. A Cox proportional hazards model was used to estimate the difference in risk of discontinuation of index therapy between CRD and non-CRD cohorts. Results: We evaluated a total of 104,135 matched pairs of CRD and non-CRD adult patients with solid or hematologic cancer; each group further grouped by those receiving either chemotherapy (n = 47,220), targeted therapy (n = 2,427), or both treatments (n = 5,313). Patients with CRD discontinued the index therapy more frequently than non-CRD patients for chemotherapy (81.5% vs 62.3%), targeted therapy (69.2% vs 64.3%) or both (96.0% vs 85.5%) (p < 0.0001). Also, the overall percentage of discontinuation (82.4% vs. 64.6%) was significantly higher among patients with CRD. The mean time to discontinuation (59.6±54.1 vs. 68.3±76.6 days) was significantly lower (p < 0.0001) in patients with CRD. The mean time to switch (72.0±48.6 vs. 96.9±84.0 days), mean persistence (95.1±98.1 vs. 154.3±142.7 days), and mean adherence (25.5%±37.2 vs. 47.9±41%) were significantly lower (all p < 0.0001) among patients with CRD compared to non-CRD. The percentage of patients requiring a dose titration for their index cancer therapy was significantly higher (21.8%) for the CRD cohort versus 8.5% for non-CRD patients (p < 0.0001). Conclusions: Patients with CRD were 40% (adjusted) more likely to discontinue the index therapy than patients without CRD. The persistence of index cancer therapy and time to switch were also lower for patients with CRD. Strategies to control CRD and continue cancer therapy are urgently needed.

Characterizing unplanned resource utilization associated with cancer-related diarrhea

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Background: In clinical oncology practice, diarrhea is a very common and severe side effect of cancer treatments including from radiotherapy, chemotherapy, and targeted therapies. Cancer-related diarrhea (CRD) leads to increased healthcare resource consumption due to unscheduled outpatient visits, and , increased hospital stays requiring intensive supportive care measures. We evaluated CRD patients receiving chemotherapy, targeted therapy, or both, requiring emergency department (ED), physician office visits, hospitalizations, and length of stay (LOS) compared to a matched cohort of non-CRD patients. Methods: We performed a longitudinal study among adult patients ( > 18 yrs) with CRD identified by diagnosis codes or pharmacy claims compared to matched non-CRD patients using claims data derived from the IQVIA PharMetrics Plus database. Index date was the first cancer claim date and patients were re-indexed based on their CRD claim. Each patient had a 6-month pre-index period, a minimum 3-month post-index period and had ≥12 months of continuous enrollment following the CRD index date. To adjust for selection bias and baseline differences, we matched CRD patients to non-CRD patients (1:1) by age, gender, geography and payer type. Patients were stratified by cancer therapy type (chemotherapy, targeted therapy or both treatments). We reported proportion of patients with hospitalizations, average length of stay (LOS), and ED visits. A generalized estimating equation model with log link and binomial distribution adjusted for type of cancer, therapy, and Charlson Comorbidity Index (CCI) was built to estimate the difference in occurrence of hospitalization between CRD and non-CRD cohorts. Results: We evaluated a total of 104,135 matched pairs of CRD and non-CRD adult patients with solid or hematologic cancer with 12-month continuous enrollment. The proportion of patients with ED visits (36.2% vs 18.9%, p < 0.0001) and hospitalizations (29.6% vs 12.8%, p < 0.0001) were significantly higher among CRD versus non-CRD cohort. When compared to non-CRD patients, CRD patients were more likely to be hospitalized (adjusted OR 2.28. 95% CI of 2.23-2.33). Mean CRD-specific office/hospital visits were significantly higher in the CRD cohort compared to the non-CRD cohort over the 12-month post-index period and patients had more CRD-specific visits to ED (7.5% vs 1.8%); physician’s offices (14.7% vs 3.8%); laboratory testing (11.6% vs 3.2%) and outpatient ancillary services (10.9% vs 2.6%) (all p < 0.0001). Mean hospital LOS among patients with CRD was higher than non-CRD patients (6.6±8.9 vs 5.8±10.5 days, p < 0.0001). Conclusions: Patients with CRD used significantly more resources, including outpatient services, ED visits, and hospitalizations. Effective prevention of CRD remains an unmet strategy to reduce the overall cost of cancer care.

Healthcare utilization and costs associated with cancer-related diarrhea

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Background: Diarrhea is a common toxicity of cancer treatments, including radiotherapy, chemotherapy, and/or targeted therapies. Cancer-related diarrhea (CRD) leads to increased healthcare utilization and cost. This study evaluated the all-cause and CRD-specific healthcare utilization and cost of patients with CRD compared to a matched non-CRD cohort. Methods: We conducted a longitudinal observational study among adult patients ( > 18 years) with CRD using diagnosis codes or pharmacy claims compared to matched non-CRD patients using claims data from the IQVIA PharMetrics Plus database (October 2015 to March 2020). The index date was the date of the first cancer claim, and we re-indexed patients based on their CRD claim. Each patient had a 6-month pre-index period and a minimum 3-month post-index period. Patients were also required to have ≥12 months of continuous enrollment following the CRD index date. We directly matched patients 1:1 from the CRD cohort to the non-CRD cohort to adjust for selection bias and baseline differences. Our aim was to compare all-cause healthcare costs over a fixed 12-month post-index period, converting all costs to 2020 USD using the Consumer Price Index's medical component. We analyzed healthcare utilization for CRD-treated, CRD-inadequately treated, and CRD-untreated sub-cohorts (per Buono et al., J Econ 2017). Secondary endpoints included healthcare cost (proportion of patients, per-patient mean and median) and healthcare utilization (prescription fills and visits to the emergency department [ED], physician office, lab/pathology and outpatient ancillary services). We built one generalized estimating equation model with log link and gamma distribution adjusted for type of cancer, therapy and Charlson Comorbidity Index (CCI) to estimate the difference in total healthcare cost between CRD and non-CRD cohorts. Results: We evaluated a total of 104,135 matched pairs of CRD and non-CRD adult patients with solid or hematologic cancer receiving either targeted or chemotherapy, with 12-month continuous enrollment. Patients with CRD incurred significantly higher mean ($104,880 vs $39,664, p < 0.0001) and median ($59,969 vs $8,914, p < 0.0001) all-cause healthcare cost compared to patients without CRD over the 12-month post-index period. Inadequately treated CRD patients had the mean highest cost ($129,531) vs adequately CRD-treated ($107,050) or untreated CRD patients ($56,350) (all p < 0.0001). Mean pharmacy cost for CRD and non-CRD patients were ($35,190 vs $15,883); visits to the ED ($1,107 vs $431), physician office ($3,457 vs $2,058), lab/pathology ($4,074 vs $1,404), and outpatient ancillary services ($15,805 vs $4,940) (all p-values < 0.0001). Conclusions: Our findings show that patients with CRD had nearly 2.9 times higher all-cause total cost than patients without CRD after adjusting for covariates. Prevention of CRD may result in a significant reduction in cancer-treatment cost.

YAP-dependent proliferation by a small molecule targeting annexin A2

The transcriptional coactivator Yes-associated protein 1 (YAP) orchestrates a proproliferative transcriptional program that controls the fate of somatic stem cells and the regenerative responses of certain tissues. As such, agents that activate YAP may hold therapeutic potential in disease states exacerbated by insufficient proliferative repair. Here we report the discovery of a small molecule, termed PY-60, which robustly activates YAP transcriptional activity in vitro and promotes YAP-dependent expansion of epidermal keratinocytes in mouse following topical drug administration. Chemical proteomics revealed the relevant target of PY-60 to be annexin A2 (ANXA2), a protein that directly associates with YAP at the cell membrane in response to increased cell density. PY-60 treatment liberates ANXA2 from the membrane, ultimately promoting a phosphatase-bound, nonphosphorylated and transcriptionally active form of YAP. This work reveals ANXA2 as a previously undescribed, druggable component of the Hippo pathway and suggests a mechanistic rationale to promote regenerative repair in disease.

High-Throughput Screening for Drugs That Inhibit Papain-Like Protease in SARS-CoV-2

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in late 2019 has triggered an ongoing global pandemic whereby infection may result in a lethal severe pneumonia-like disease designated as coronavirus disease 2019 (COVID-19). To date, millions of confirmed cases and hundreds of thousands of deaths have been reported worldwide, and there are currently no medical countermeasures available to prevent or treat the disease. The purported development of a vaccine could require at least 1–4 years, while the typical timeline from hit finding to drug registration of an antiviral is >10 years. Thus, repositioning of known drugs can significantly accelerate the development and deployment of therapies for COVID-19. To identify therapeutics that can be repurposed as SARS-CoV-2 antivirals, we developed and initiated a high-throughput cell-based screen that incorporates the essential viral papain-like protease (PLpro) and its peptide cleavage site into a luciferase complementation assay to evaluate the efficacy of known drugs encompassing approximately 15,000 clinical-stage or US Food and Drug Administration (FDA)-approved small molecules. Confirmed inhibitors were also tested to determine their cytotoxic properties. Here, we report the identification of four clinically relevant drugs that exhibit selective inhibition of the SARS-CoV-2 viral PLpro.

Small-Molecule Stimulators of NRF1 Transcriptional Activity

The transcription factor nuclear factor erythroid 2-related factor 1 (NRF1) maintains proteostasis and promotes cellular resilience by stimulating the transcription of proteasomal subunits and a host of protective enzymes. Although NRF1 activation would likely be beneficial in a number of disease states, information regarding its ligandability and upstream regulation are lacking. Herein we report a high-throughput chemical screen that identified selective stimulators of NRF1-driven transcription, including unannotated inhibitors of the ubiquitin proteasome system (UPS) as well as two non-UPS-targeted compounds that synergistically activate NRF1 in the context of submaximal UPS inhibition. This work introduces a suite of tool molecules to study the NRF1 transcriptional response and to uncover the druggable components governing NRF1 activity in cells.

Continuous synthesis of Zn2Al–CO3layered double hydroxides: a comparison of bench, pilot and industrial scale syntheses

Zn₂Al–CO₃was produced continuously at bench (g h⁻¹), pilot (100s g h⁻¹) and industrial scale (10s kg h⁻¹).

Obesity surgery and risk of cancer

BACKGROUND

Obesity increases the risk of several types of cancer. Whether bariatric surgery influences the risk of obesity-related cancer is not clear. This study aimed to uncover the risk of hormone-related (breast, endometrial and prostate), colorectal and oesophageal cancers following obesity surgery.

METHODS

This national population-based cohort study used data from the Hospital Episode Statistics database in England collected between 1997 and 2012. Propensity matching on sex, age, co-morbidity and duration of follow-up was used to compare cancer risk among obese individuals undergoing bariatric surgery (gastric bypass, gastric banding or sleeve gastrectomy) and obese individuals not undergoing such surgery. Conditional logistic regression provided odds ratios (ORs) with 95 per cent confidence intervals.

RESULTS

In the study period, from a cohort of 716 960 patients diagnosed with obesity, 8794 patients who underwent bariatric surgery were matched exactly with 8794 obese patients who did not have surgery. Compared with the no-surgery group, patients who had bariatric surgery exhibited a decreased risk of hormone-related cancers (OR 0·23, 95 per cent c.i. 0·18 to 0·30). This decrease was consistent for breast (OR 0·25, 0·19 to 0·33), endometrium (OR 0·21, 0·13 to 0·35) and prostate (OR 0·37, 0·17 to 0·76) cancer. Gastric bypass resulted in the largest risk reduction for hormone-related cancers (OR 0·16, 0·11 to 0·24). Gastric bypass, but not gastric banding or sleeve gastrectomy, was associated with an increased risk of colorectal cancer (OR 2·63, 1·17 to 5·95). Longer follow-up after bariatric surgery strengthened these diverging associations.

CONCLUSION

Bariatric surgery is associated with decreased risk of hormone-related cancers, whereas gastric bypass might increase the risk of colorectal cancer.

Targeted Disruption of Myc-Max Oncoprotein Complex by a Small Molecule

Myc plays important roles in cell cycle progression, cell growth, and stem cell self-renewal. Although dysregulation of Myc expression is a hallmark of human cancers, there is no Myc targeted therapy yet. Here, we report sAJM589, a novel small molecule Myc inhibitor, identified from a PCA-based high-throughput screen. sAJM589 potently disrupts the Myc-Max heterodimer in a dose dependent manner with an IC₅₀ of 1.8 ± 0.03 μM. sAJM589 preferentially inhibits transcription of Myc target genes in a Burkitt lymphoma cell model, P493-6. Genome-wide transcriptome analysis showed that sAJM589 treatment and Myc depletion induced similar gene expression profiles. Consistently, sAJM589 suppressed cellular proliferation in diverse Myc-dependent cancer cell lines and anchorage independent growth of Raji cells. Disruption of the Myc-Max interaction by sAJM589 reduced Myc protein levels, possibly by promoting ubiquitination and degradation of Myc. Collectively, these results suggest that sAJM589 may be a basis for the development of potential inhibitors of Myc-dependent cell growth.

Ex Vivo Cell-Based Screening Platform for Modulators of Hepatosteatosis

Nonalcoholic fatty liver disease (NAFLD) is the result of the ectopic accumulation of lipids in hepatic cells and is the early stage of liver diseases including fibrosis, cirrhosis, and hepatocellular carcinoma. While some mechanisms of aberrant lipid storage are understood, unbiased phenotypic drug screening holds the potential to identify new therapeutic small molecule mechanisms that reverse lipid accumulation in hepatic cells and prevent disease progression. Immortalized hepatocyte cell lines are often used as in vitro models of hepatocyte function, including in the study of lipid accumulation. However, mechanisms and therapeutic agents studied in these systems suffer from poor translation to primary cells and animal models of disease. Herein, we report an ex vivo high-throughput screening platform using primary mouse hepatocytes with a physiologically relevant lipid-laden phenotype isolated from mice that are administered a choline-methionine deficient diet. This screening platform using primary diseased hepatocytes may help to overcome a major hurdle in liver disease drug discovery and could lead to the development of new therapeutics for hepatosteatosis.

A tale of two countries: all-cause mortality among people living with HIV and receiving combination antiretroviral therapy in the UK and Canada

Objectives

We sought to compare all‐cause mortality of people living with HIV and accessing care in Canada and the UK.

Methods

Individuals from the Canadian Observational Cohort (CANOC) collaboration and UK Collaborative HIV Cohort (UK CHIC) study who were aged ≥ 18 years, had initiated antiretroviral therapy (ART) for the first time between 2000 and 2012 and who had acquired HIV through sexual transmission were included in the analysis. Cox regression was used to investigate the difference in mortality risk between the two cohort collaborations, accounting for loss to follow‐up as a competing risk.

Results

A total of 19 960 participants were included in the analysis (CANOC, 4137; UK CHIC, 15 823). CANOC participants were more likely to be older [median age 39 years (interquartile range (IQR): 33, 46 years) vs. 36 years (IQR: 31, 43 years) for UK CHIC participants], to be male (86 vs. 73%, respectively), and to report men who have sex with men (MSM) sexual transmission risk (72 vs. 56%, respectively) (all P < 0.001). Overall, 762 deaths occurred during 98 798 person‐years (PY) of follow‐up, giving a crude mortality rate of 7.7 per 1000 PY [95% confidence interval (CI): 7.1, 8.3 per 1000 PY]. The crude mortality rates were 8.6 (95% CI: 7.4, 10.0) and 7.5 (95% CI: 6.9, 8.1) per 1000 PY among CANOC and UK CHIC study participants, respectively. No statistically significant difference in mortality risk was observed between the cohort collaborations in Cox regression accounting for loss to follow‐up as a competing risk (adjusted hazard ratio 0.86; 95% CI: 0.72–1.03).

Conclusions

Despite differences in national HIV care provision and treatment guidelines, mortality risk did not differ between CANOC and UK CHIC study participants who acquired HIV through sexual transmission.

Awareness and use of nonoccupational post-exposure prophylaxis among men who have sex with men in Vancouver, Canada

OBJECTIVES

Nonoccupational post-exposure prophylaxis (nPEP) is a strategy to reduce the risk of HIV infection in those with high-risk exposure. This study characterized nPEP awareness among gay, bisexual and other men who have sex with men (MSM) in Metro Vancouver, British Columbia, Canada after a pilot nPEP programme established in 2012.

METHODS

Momentum Health Study participants were MSM aged ≥16 years recruited via respondent-driven sampling (RDS) who completed a computer-assisted self-interview. Stratifying patients by HIV status, we used multivariable logistic regression with backward selection to identify factors associated with nPEP awareness. All analyses were RDS-adjusted.

RESULTS

A total of 51.9% (112 of 173) of HIV-positive and 48.5% (272 of 500) of HIV-negative participants had heard of nPEP. Only 3% (five of 106) of HIV-negative participants who reported recent high-risk sex used nPEP. Generally, nPEP awareness was higher for participants who engaged in sexual activities with increased HIV transmission potential. Factors associated with greater awareness among HIV-negative participants included recent alcohol use, higher communal sexual altruism, previous sexually transmitted infection diagnosis, and greater perceived condom use self-efficacy. Other factors associated with greater awareness among HIV-negative participants included white race/ethnicity, gay sexual identity, more formal education, lower personal sexual altruism, and Vancouver residence. Greater nPEP awareness among HIV-positive participants was associated with greater perceived agency to ask sexual partners' HIV status and more frequently reporting doing so, a higher number of lifetime receptive sex partners, and greater access to condoms.

CONCLUSIONS

Following implementation of an nPEP pilot programme, nPEP awareness among HIV-negative MSM was 51% and use was 3%. These data support the need to expand access to and actively promote nPEP services.

The 'Expanded HIV care in opioid substitution treatment' (EHOST) cluster-randomized, stepped-wedge trial: A study protocol

The public health response to HIV/AIDS has turned its focus onto optimizing health care system delivery to maximize case identification, access and sustained engagement in antiretroviral treatment (ART). Opioid Agonist Treatment (OAT) provides a critical opportunity for HIV testing and linkage to ART. The EHOST study is a cluster-randomized, stepped-wedge trial to evaluate a prescriber-focused intervention to increase HIV testing rates, and optimize ART engagement and retention outcomes among individuals engaged in OAT. The study will encompass all drug treatment clinics currently admitting patients for the treatment of opioid use disorder across the province of British Columbia, encompassing an estimated 90% of the OAT caseload. The trial will be executed over a 24-month period, with groups of clinics receiving the intervention in 6-month intervals. Evaluation of the proposed intervention's effectiveness will focus on three primary outcomes: (i) the HIV testing rate among those not known to be HIV positive; (ii) the rate of ART initiation among those not on ART; and (iii) the rate of ART continuation among those on ART. A difference-in-differences analytical framework will be applied to estimate the intervention's effect. This approach will assess site-specific changes in primary outcomes across clusters while adjusting for potential residual heterogeneity in patient case mix, volume, and quality of care across clinics. Statistical analysis of outcomes will be conducted entirely with linked population-level administrative health datasets. Facilitated by established collaborations between key stakeholders across the province, the EHOST intervention promises to optimize HIV testing and care within a marginalized and hard-to-reach population.

Opioid use and risk of liver fibrosis in HIV/hepatitis C virus-coinfected patients in Canada

OBJECTIVES

Opioid use and opioid-related mortality have increased dramatically since the 1990s in North America. The effect of opioids on the liver is incompletely understood. Some studies have suggested that opioids cause liver damage and others have failed to show any harm. HIV/hepatitis C virus (HCV)-coinfected persons may be particularly vulnerable to factors increasing liver fibrosis. We aimed to describe opioid use in an HIV/HCV-coinfected population in Canada and to estimate the association between opioid use and liver fibrosis.

METHODS

We conducted a cross-sectional descriptive analysis of the Canadian Co-infection Cohort Study data to characterize opioid use. We then conducted a longitudinal analysis to assess the average change in aspartate aminotransferase-to-platelet ratio index (APRI) score associated with opioid use using a generalized estimating equation with linear regression. We assessed the progression to significant liver fibrosis (APRI ≥ 1.5) associated with opioid use with pooled logistic regression.

RESULTS

In the 6 months preceding cohort entry, 32% of the participants had received an opioid prescription, 28% had used opioids illicitly and 18% had both received a prescription and used opioids illicitly. Neither prescribed nor illicit opioid use was associated with a change in the median APRI score [exp(β) 0.99 (95% confidence interval (CI) 0.82, 1.12) and exp(β) 0.95 (95% CI 0.81, 1.10), respectively] or with faster progression to liver fibrosis [hazard odds ratio (HOR) 1.20 (95% CI 0.73, 1.67) and HOR 1.09 (95% CI 0.63, 1.55), respectively].

CONCLUSIONS

Although opioids were commonly used both legally and illegally in our cohort, we were unable to demonstrate a negative impact on liver fibrosis progression.

Rational design of CXCR4 specific antibodies with elongated CDRs

The bovine antibody (BLV1H12) which has an ultralong heavy chain complementarity determining region 3 (CDRH3) provides a novel scaffold for antibody engineering. By substituting the extended CDRH3 of BLV1H12 with modified CXCR4 binding peptides that adopt a β-hairpin conformation, we generated antibodies specifically targeting the ligand binding pocket of CXCR4 receptor. These engineered antibodies selectively bind to CXCR4 expressing cells with binding affinities in the low nanomolar range. In addition, they inhibit SDF-1-dependent signal transduction and cell migration in a transwell assay. Finally, we also demonstrate that a similar strategy can be applied to other CDRs and show that a CDRH2-peptide fusion binds CXCR4 with a K(d) of 0.9 nM. This work illustrates the versatility of scaffold-based antibody engineering and could greatly expand the antibody functional repertoire in the future.

HIV and hepatitis C virus coinfection in Canada: challenges and opportunities for reducing preventable morbidity and mortality

OBJECTIVES

Hepatitis C virus (HCV) has emerged as an important health problem in the era of effective HIV treatment. However, very few data exist on the health status and disease burden of HIV/HCV-coinfected Canadians.

METHODS

HIV/HCV-coinfected patients were enrolled prospectively in a multicentre cohort from 16 centres across Canada between 2003 and 2010 and followed every 6 months. We determined rates of a first liver fibrosis or endstage liver disease (ESLD) event and all-cause mortality since cohort enrolment and calculated standardized mortality ratios compared with the general Canadian population.

RESULTS

A total of 955 participants were enrolled in the study and followed for a median of 1.4 (interquartile range 0.5-2.3) years. Most were male (73%) with a median age of 44.5 years; 13% self-identified as aboriginal. There were high levels of current injecting drug and alcohol use and poverty. Observed event rates [per 100 person-years; 95% confidence interval (CI)] were: significant fibrosis (10.21; 8.49, 12.19), ESLD (3.16; 2.32, 4.20) and death (3.72; 2.86, 4.77). The overall standardized mortality ratio was 17.08 (95% CI 12.83, 21.34); 12.80 (95% CI 9.10, 16.50) for male patients and 28.74 (95% CI 14.66, 42.83) for female patients. The primary causes of death were ESLD (29%) and overdose (24%).

CONCLUSIONS

We observed excessive morbidity and mortality in this HIV/HCV-coinfected population in care. Over 50% of observed deaths may have been preventable. Interventions aimed at improving social circumstances, reducing harm from drug and alcohol use and increasing the delivery of HCV treatment in particular will be necessary to reduce adverse health outcomes among HIV/HCV-coinfected persons.

507. TGFβ REGULATES ENDOMETRIOSIS-LIKE LESION DEVELOPMENT IN MICE INDEPENDENTLY OF THE RUNX-2/OPN PATHWAY

TGFβ is likely to significantly influence endometriotic lesion development, as TGFβ KO/SCID mice with no host-derived TGFβ activity have smaller human ectopic endometrial lesions than control mice. TGFβ potentially acts via RUNX2, a transcription factor that directly upregulates OPN transcription in osteoblasts, as we have identified RUNX-2 and OPN gene expression at high levels in nude mouse endometriosis-like lesions, in human endometrial stomal cell cultures and in the stroma of endometriotic tissues. We hypothesised that inhibition of RUNX-2 would suppress OPN production and result in reduction of endometriotic lesion formation and size. As P38/MAPK inhibitors suppress TGF-β mediated RUNX-2 transcription, we utilised the nude mouse model to test whether the P38/MAPK inhibitor FR167653 would suppress OPN production in endometriotic tissues resulting in smaller lesions.FR167653 (30 mg/kg twice a day) or placebo was administered for either 10 or 14 days to nude mice (16 in each group) implanted with human endometrial tissue xenografts from 4 different women. The size and weight of the lesions were measured and immunohistochemical analysis of OPN, αSMA (myofibroblasts) and F4/80 (macrophages) was carried out. There was no difference in size or weight of the lesions, and there was no overt difference in any of the staining parameters explored. The inhibition of p38/MAPK did not alter the size of the nude mouse lesions nor OPN staining within these lesions despite being administered at a maximal therapeutic dose. This suggests that TGFβ regulation of endometriotic lesion development is mediated by an alternate molecular pathway.

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.

Methicillin-resistant Staphylococcus aureus infection of percutaneous endoscopic gastrostomy sites

BACKGROUND

Antibiotic prophylaxis for percutaneous endoscopic gastrostomy insertion remains controversial. The bacteriology of peristomal infection following percutaneous endoscopic gastrostomy insertion has been poorly studied, leading to uncertainty regarding the optimum choice of antibiotic for prophylaxis.

AIM

To investigate the bacteriology of peristomal infection following percutaneous endoscopic gastrostomy insertion and to determine the contribution of methicillin-resistant Staphylococcus aureus.

METHODS

Nasal and pharyngeal swabs were taken from a consecutive series of patients prior to percutaneous endoscopic gastrostomy insertion over a 6-month period. Bacterial colonization and infection at the peristomal site were prospectively evaluated at days 2/3 and 7 post-insertion.

RESULTS

Thirty-one patients underwent percutaneous endoscopic gastrostomy insertion (mean age, 68 years; cerebrovascular disease, 52%). Naso-pharyngeal colonization by methicillin-resistant Staphylococcus aureus (35%) invariably led to peristomal colonization following percutaneous endoscopic gastrostomy insertion. Peristomal infection occurred in eight (26%) cases (seven (88%) methicillin-resistant Staphylococcus aureus- positive). Peristomal infection was significantly more likely to occur in patients with naso-pharyngeal methicillin-resistant Staphylococcus aureus colonization (odds ratio, 10.8; 95% confidence interval, 1.6-70.9).

CONCLUSIONS

Naso-pharyngeal methicillin-resistant Staphylococcus aureus colonization invariably predicts peristomal methicillin-resistant Staphylococcus aureus colonization following percutaneous endoscopic gastrostomy insertion, and is associated with an increased peristomal infection rate. Currently recommended antibiotic prophylaxis regimens may be inappropriate in institutions with significant methicillin-resistant Staphylococcus aureus colonization rates.

Struggling with paradoxes: the process of spiritual development in women with cancer

PURPOSE/OBJECTIVES

To examine the process of spiritual development in women diagnosed with cancer within five years of initial treatment.

DESIGN

Exploratory, qualitative.

SETTING

Outpatients in the mid-central and southwestern United States.

SAMPLE

10 Caucasian women, ages 45-70, who completed initial treatment, were not undergoing treatment for recurrence, and were within five years of diagnosis for breast or ovarian cancer or non-Hodgkin's lymphoma.

METHODS

Data collected during two semistructured interviews, coded and analyzed using grounded theory techniques. Frame of reference--symbolic interactionism.

MAIN RESEARCH VARIABLES

Developmental processes of spirituality; responses to diagnosis, treatment, and survival of cancer.

FINDINGS

Diagnosis of cancer threatened the meaning of the women's lives, resulting in a sense of disintegration. This problem was resolved through the basic social psychological process of Struggling With Paradoxes, a three-phase process of Deciphering the Meaning of Cancer for Me, Recognizing Human Limitations, and Learning to Live with Uncertainty. In phase I, the paradoxes focused on the possibility of death, distress, vulnerability, and maintaining connection. In phase II, the paradoxes involved confronting death, asking difficult questions, and letting go of ultimate control of their lives. In phase III, the paradoxes centered on uncertainty, redefining meaning, and identifying spiritual growth. Reintegration occurred over time, although when threatened by the possibility of recurrence, disintegration resurfaced for a time.

CONCLUSIONS

Findings emphasize not only the importance of spirituality, but also that spiritual experience is individualized and developmental in nature. Spiritual growth occurs over time following the diagnosis of cancer and is not necessarily related to age.

IMPLICATIONS FOR NURSING PRACTICE

Spiritual concerns may be painful for patients to address; spiritual caregiving requires an acknowledgment of need by the woman with cancer and a caring, sensitive caregiver. Nurses should be aware of the phases of spiritual development so that interventions can be designed to address individual needs that may vary over time.

Elevated plasma neopterin levels in Alzheimer disease

We assessed plasma neopterin level as a marker of inflammation in Alzheimer disease (AD). Plasma neopterin levels were higher in 51 patients with AD (9.3 +/- 5.9 ng/mL) than in 38 age-matched control subjects (6.3 +/- 2.6 ng/ml, p = 0.002). There was no correlation between neopterin levels and Mini-Mental State Examination score or duration of disease; there was a weak association between neopterin level and age (r = 0.26, p = 0.02). Although measurement of plasma neopterin levels is not useful for diagnosis, this assay may provide guidance for the development of anti-inflammatory treatment strategies for AD.

Comparison of therapy detection times between implantable cardioverter defibrillators with standard dual- and single-chamber pacing

Previous implantable cardioverter defibrillators (ICDs) required patients in need of dual-chamber (DDD) pacing for improved hemodynamic status to undergo implantation of separate devices to treat bradycardia and/or ventricular arrhythmias. An investigation was conducted to verify the performance of a new ICD that combines both therapies.Sixty-nine patients at 17 European and Canadian centers were implanted with VENTAK AV models 1810/1815, ICD's that includes DDD pacing and algorithms designed to differentiate between atrial and ventricular arrhythmias. 36 of the cohort were compared to 32 patients tested at six centers with an external test device (VENTAK MINI). In both cohorts detection times were calculated for ventricular fibrillation (VF) induced at implant. The mean detection times (DT) from the VENTAK AV device were compared to the DT from the VENTAK MINI device. Patient characteristics of the VENTAK AV and the VENTAK MINI control groups were similar. Mean VF detection time (+/-SD) with the VENTAK AV device was 2.21 +/- 0.54 seconds, as compared with 1.87 +/- 0.62 seconds with the VENTAK MINI (p < 0.01), indicating that the difference in means did not exceed one second. The VENTAK AV system function did not demonstrate interaction with the pacemaker function, as indicated by the clinical significance with the detection times of the study device. The difference in detection times between cohorts did not statistically exceed one second. Appropriate detection of the new ICD was not compromised by the addition of the dual-chamber pacing therapy.

Phase III interlaboratory study of FETAX. Part 3. FETAX validation using 12 compounds with and without an exogenous metabolic activation system

FETAX (Frog Embryo Teratogenesis Assay-Xenopus) is a 96-h whole-embryo developmental toxicity screening assay that can be used in ecotoxicology and in detecting mammalian developmental toxicants when an in vitro metabolic activation system is employed. A standardized American Society for Testing and Materials (ASTM) guide for the conduct of FETAX has been published, along with a companion atlas that helps in embryo staging and in identifying malformations. As part of the ASTM process, an interlaboratory validation study was undertaken to evaluate the repeatability and reliability of FETAX and to evaluate the potential teratogenic hazard of 12 compounds. Three different laboratories participated in the study. All three participating laboratories had extensive experience with the assay. FETAX intralaboratory and interlaboratory variability, as judged by coefficients of variation, were very low. Potential teratogenic hazard was evaluated using two major criteria from FETAX experiments employing metabolic activation systems (MAS). These were the teratogenic index TI (TI = 96-h lc(50)/96-h ec(50) (malformation)) and the minimum concentration that inhibits growth (MCIG). A compound was considered teratogenic by this criterion when the MCIG was significantly different from controls at concentrations below the 30% level of the MAS 96-h lc(50). Based on the results of this and other studies, a decision table was constructed in order to evaluate additional studies. Severity of malformations caused, especially near the MAS 96-h ec(50) (malformation), were also evaluated. Four compounds were non-teratogenic but two compounds were clearly teratogenic. The remaining six compounds were ranked as equivocal teratogens. The results were discussed in light of the difficulty of producing an adequate decision table. FETAX proved to yield repeatable and reliable data as long as care was taken during range-finding and technicians were adequately trained. The MAS was essential in using FETAX to predict developmental hazard in mammals, and still requires further development.

Older road users. Issues for general practitioners

BACKGROUND

As our population ages it is anticipated that a greater number of older drivers will be on the roads. This raises the possibility of an increased number of road crashes. Predictors of increased risk of road accidents need to be identified in order for appropriate advice to be given on how to reduce the road risk.

OBJECTIVE

This article aims to provide insights about the problems posed by older drivers together with practical guidance for general practitioners.

DISCUSSION

Advice from medical practitioners is often heeded by older patients in relation to their ability to drive. Using resources such as Assessing Fitness to Drive will aid the GP in making an informed decision in relation to this.

Protection against aspirin-induced human gastric mucosal injury by bosentan, a new endothelin-1 receptor antagonist

BACKGROUND

Gastric ulceration induced by aspirin and by non-steroidal anti-inflammatory drugs (NSAIDs) is a major clinical problem. The mechanism of injury is unclear. There is evidence that NSAID-induced injury may cause endothelin activation. Endothelin-induced vasoconstriction has been shown to be capable of causing gastric ulceration.

AIM

To investigate whether acute gastroduodenal injury induced in humans by aspirin can be prevented by the endothelin-1 antagonist, bosentan.

METHODS

Eighteen healthy volunteers each received 5 x 900 mg aspirin every 12 h on three separate occasions (with either placebo, bosentan 700 mg or misoprostol 400 mg). Treatment order was randomized by Latin square design. Subjects were endoscoped and erosions counted before and 90 min after the first and last dose of aspirin. Plasma concentrations of bosentan were measured up to 5 h post-dose.

RESULTS

There was a significant reduction in the mean number of erosions in the aspirin plus bosentan and aspirin plus misoprostol groups after the first dose of aspirin, compared with controls (aspirin plus placebo) (P<0.05). This was not sustained after the fifth dose of aspirin in the aspirin plus placebo and aspirin plus bosentan groups, but was still present in the aspirin plus misoprostol group. The mean plasma concentration of bosentan measured 3.5 h post-dose fell from 4510 (95% CI: 2791-6230) ng/mL after the 1st dose to 2508 (95% CI: 1733-3283) ng/mL after the 5th dose (P = 0.02).

CONCLUSION

Endothelin receptor antagonism by bosentan can protect the gastric mucosa against aspirin damage. After five doses, bosentan levels fell, possibly because of enzyme induction, and protection was no longer evident. Further investigation is needed to assess whether higher doses would be effective.

The receptor recycling pathway contains two distinct populations of early endosomes with different sorting functions

Receptor recycling involves two endosome populations, peripheral early endosomes and perinuclear recycling endosomes. In polarized epithelial cells, either or both populations must be able to sort apical from basolateral proteins, returning each to its appropriate plasma membrane domain. However, neither the roles of early versus recycling endosomes in polarity nor their relationship to each other has been quantitatively evaluated. Using a combined morphological, biochemical, and kinetic approach, we found these two endosome populations to represent physically and functionally distinct compartments. Early and recycling endosomes were resolved on Optiprep gradients and shown to be differentially associated with rab4, rab11, and transferrin receptor; rab4 was enriched on early endosomes and at least partially depleted from recycling endosomes, with the opposite being true for rab11 and transferrin receptor. The two populations were also pharmacologically distinct, with AlF4 selectively blocking export of transferrin receptor from recycling endosomes to the basolateral plasma membrane. We applied these observations to a detailed kinetic analysis of transferrin and dimeric IgA recycling and transcytosis. The data from these experiments permitted the construction of a testable, mathematical model which enabled a dissection of the roles of early and recycling endosomes in polarized receptor transport. Contrary to expectations, the majority (>65%) of recycling to the basolateral surface is likely to occur from early endosomes, but with relatively little sorting of apical from basolateral proteins. Instead, more complete segregation of basolateral receptors from receptors intended for transcytosis occurred upon delivery to recycling endosomes.