Efficacy and safety of intrathecal pemetrexed for TKI-failed leptomeningeal metastases from EGFR+ NSCLC: an expanded, single-arm, phase II clinical trial

BACKGROUND

This study aimed to evaluate the efficacy and safety of intrathecal pemetrexed (IP) for treating patients with leptomeningeal metastases (LM) from non-small-cell lung cancer (NSCLC) who progressed from epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment in an expanded, prospective, single-arm, phase II clinical study (ChiCTR1800016615).

PATIENTS AND METHODS

Patients with confirmed NSCLC-LM who progressed from TKI received IP (50 mg, day 1/day 5 for 1 week, then every 3 weeks for four cycles, and then once monthly) until disease progression or intolerance. Objectives were to assess overall survival (OS), response rate, and safety. Measurable lesions were assessed by investigator according to RECIST version 1.1. LM were assessed according to the Response Assessment in Neuro-Oncology (RANO) criteria.

RESULTS

The study included 132 patients; 68% were female and median age was 52 years (31-74 years). The median OS was 12 months (95% confidence interval 10.4-13.6 months), RANO-assessed response rate was 80.3% (106/132), and the most common adverse event was myelosuppression (n = 42; 31.8%), which reversed after symptomatic treatment. The results of subgroup analysis showed that absence of brain parenchymal metastasis, good Eastern Cooperative Oncology Group score, good response to IP treatment, negative cytology after treatment, and patients without neck/back pain/difficult defecation had longer survival. Gender, age, previous intrathecal methotrexate/cytarabine, and whole-brain radiotherapy had no significant influence on OS.

CONCLUSIONS

This study further showed that IP is an effective and safe treatment method for the EGFR-TKI-failed NSCLC-LM, and should be recommended for these patients in clinical practice and guidelines.

The Risk and Clinical Implications of Antibiotic-Associated Acute Kidney Injury: A Review of the Clinical Data for Agents with Signals from the Food and Drug Administration’s Adverse Event Reporting System (FAERS) Database

Antibiotic-associated acute kidney injury (AA-AKI) is quite common, especially among hospitalized patients; however, little is known about risk factors or mechanisms of why AA-AKI occurs. In this review, the authors have reviewed all available literature prior to 1 June 2022, with a large number of AKI reports. Information regarding risk factors of AA-AKI, mechanisms behind AA-AKI, and treatment/management principles to decrease AA-AKI risk were collected and reviewed. Patients treated in the inpatient setting are at increased risk of AA-AKI due to common risk factors: hypovolemia, concomitant use of other nephrotoxic medications, and exacerbation of comorbid conditions. Clinicians should attempt to correct risk factors for AA-AKI, choose antibiotic therapies with decreased association of AA-AKI to protect their high-risk patients, and narrow, when clinically possible, the use of antibiotics which have decreased incidence of AKI. To treat AKI, it is still recommended to discontinue all offending nephrotoxic agents and to renally adjust all medications according to package insert recommendations to decrease patient harm.

From Start to Finish: Examining factors associated with higher likelihood of publication among abstracts presented at an international infectious diseases scientific meeting

Background

The landscape of infectious diseases research by interprofessional teams continues to change in both scope and engagement. Limited information exists regarding publication metrics and factors associated with publication of abstracts presented at professional infectious diseases meetings.

Methods

This was a retrospective, observational study evaluating abstracts presented at IDWeek in 2017 and 2018. The primary endpoint was the proportion of abstracts that were subsequently published in peer-reviewed journals. Factors associated with publication were evaluated and a description of publication metrics was reported.

Results

Of the 887 abstracts analyzed from the IDWeek meetings, 236 (26.6%) were published. Significantly more abstracts were published if they were presented as a platform presentation versus poster presentation (35% vs. 21%, p < 0.001). Inclusion of a PhD author significantly increased the likelihood of publication (p = 0.0014). Prospective studies, greater number of authors, and greater number of study subjects were more common among published abstracts. Median time to publication was 10.9 months and the majority were published in infectious diseases journals with an overall average impact factor of 7.7 across all journals.

Conclusion

Abstracts from IDWeek presented as oral platforms and those including a PhD author were more likely to be published. Large, diverse authorship teams were common among published abstracts. The high quality of resulting manuscripts is evident by the destination journals and their respective impact factors. These data may be used to inform and motivate clinicians and trainees engaging in infectious diseases related research.

Retrospective Cohort Evaluating the Comparative Effectiveness of Ceftaroline and Daptomycin as First-Line Therapies for Inpatient Treatment of Diabetic Foot Infection in the United States Veterans Health Care System

BACKGROUND

Both ceftaroline and daptomycin are possible therapeutic options for diabetic foot infection (DFI) and both are active against methicillin-resistant Staphylococcus aureus (MRSA) infection; however, no previous studies have evaluated their effectiveness head-to-head.

OBJECTIVE

This study compared hospital readmission and mortality proportions among patients receiving ceftaroline fosamil or daptomycin for DFI.

PATIENTS AND METHODS

This was a retrospective cohort, comparative effectiveness study of adults (aged ≥ 18 years) admitted to United States Veterans Health Care System hospitals with a diagnosis code for DFI between 1 October 2010 and 30 September 2014 with an electronic order for ceftaroline or daptomycin as first-line therapy within 14 days of admission. Baseline characteristics were compared using Chi-square, Fisher's exact, and Wilcoxon rank-sum tests. Hospital readmission and patient mortality proportions were compared through multivariable logistic regression models with Hispanic ethnicity, prior hospitalization, dyslipidemia, and Charlson comorbidity score as covariates.

RESULTS

In total, 223 patients were included (ceftaroline, n = 71; daptomycin n = 152). At baseline, ceftaroline patients were more likely to be Hispanic (18 vs. 6%, p < 0.01) and have been hospitalized in the past 90 days (34 vs. 19%, p = 0.02). Unadjusted 90-day hospital readmission proportions for ceftaroline versus daptomycin were 34 vs. 49%, and unadjusted 90-day mortality proportions were 1% vs. 8%. In multivariable models, ceftaroline patients were less likely to experience 90-day hospital readmission (odds ratio [OR] 0.46, 95% confidence interval [CI] 0.25-0.85) and 90-day mortality (OR 0.14, 95% CI 0.01-0.77).

CONCLUSIONS

In this population, ceftaroline was associated with lower 90-day hospital readmission and 90-day mortality compared with daptomycin when used as first-line therapy for DFI.

Comparative Safety Signal Assessment of Hospitalization Associated With the Use of Atypical Antipsychotics

Background

Persons with symptoms of psychosis receiving treatment with atypical antipsychotics (AAPs) can experience serious adverse events (AEs) requiring admission to the hospital. The comparative likelihood of AE-related hospitalization following the use of all AAPs has not been fully characterized. Therefore, we evaluated the safety signals of hospitalizations associated with the use of AAPs.

Methods

We conducted a cross-sectional analysis using the FDA Adverse Event Reporting System (FAERS) database (from January 1, 2004, to December 31, 2021) to examine disproportionality in reporting hospitalizations suspected to be associated with 12 AAPs (aripiprazole, asenapine, brexpiprazole, clozapine, iloperidone, lurasidone, olanzapine, paliperidone, and pimavanserin, quetiapine, risperidone, and ziprasidone). Hospitalization in the FAERs database is an outcome that is recorded as a result of an AE occurring at any drug dose. We estimated reporting odds ratios (RORs) by comparing the odds of hospitalization occurring with a particular AAP to the odds of its occurrence with other drugs. In addition, we considered the presence of a significant safety signal when the lower limit of the 95% confidence interval (CI) of the ROR is >1.

Results

A total of 204,287 cases of hospitalizations were reported to the FDA for individuals treated with AAPs. There were significant safety signals of hospitalization associated with using clozapine (ROR, 2.88; 95% CI, 2.84-2.92), olanzapine (ROR, 2.61; 95% CI, 2.57-2.64), quetiapine (ROR, 1.87; 95% CI, 1.85-1.89), risperidone (ROR, 1.41; 95% CI, 1.39-1.43), aripiprazole (ROR, 1.34; 95% CI, 1.32-1.35), and ziprasidone (ROR, 1.14; 95% CI, 1.10-1.18). However, no hospitalization-related safety signals were observed with the use of paliperidone, pimavanserin, iloperidone, asenapine, lurasidone, and brexpiprazole. The ROR estimates were numerically higher among older adults than younger adults.

Conclusions

This cross-sectional assessment of data from FAERs (2004-2021) suggested that users of clozapine, olanzapine, quetiapine, risperidone, aripiprazole, and ziprasidone were more likely to report being hospitalized than users of other AAPs. Given that the FAERs database only contains spontaneous reports of AEs experienced by persons exposed to a drug but without information on exposed persons who did not have an event, a cohort study comparing hospitalizations among new users of individual AAPs against each other is needed to delineate these safety signals further.

In vitro activity of non-antibiotic drugs against Staphylococcus aureus clinical strains

OBJECTIVES

We hypothesised that one or more of the non-antibiotic candidates selected for this study would demonstrate antibiotic activity against Staphylococcus aureus.

METHODS

We determined minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) for non-antibiotic drugs (amlodipine, azelastine, ebselen and sertraline) against five clinical S. aureus isolates and one quality control strain using the Microplate Alamar Blue Assay (MABA). Our research group selected clinical isolates obtained from nasal and wound swab cultures of patients with skin and soft-tissue infections who were seen at primary care clinics in the South Texas Ambulatory Research Network (STARNet).

RESULTS

Three of the non-antibiotic drugs had identical MICs for all isolates: amlodipine, 64 μg/mL; azelastine, 200 μg/mL; and sertraline, 20 μg/mL. MICs for ebselen were 0.25 μg/mL (SA-29213, A1019 and J1019), 0.5 μg/mL (A32 and B60) and 1 μg/mL (B72). MBCs for amlodipine, azelastine and sertraline were within one dilution of their MICs, indicating bactericidal activity for all test isolates. Ebselen MBCs were one to two dilutions higher in most isolates, also indicating bactericidal activity for all test isolates.

CONCLUSION

In summary, all four non-antibiotics demonstrated in vitro activity to varying degrees against S. aureus clinical isolates. Ebselen was the most potent of the four non-antibiotics tested.

Delirium Associations with Antibiotics: A Pharmacovigilance Study of the FDA Adverse Event Reporting System (FAERS)

Background

Ertapenem, cefepime, imipenem, ofloxacin, ceftazidime, clarithromycin, cefaclor, levofloxacin, linezolid, moxifloxacin, azithromycin, piperacillin–tazobactam, trimethoprim–sulfamethoxazole, metronidazole, ciprofloxacin, and cefuroxime are known to be associated with delirium. Other antibiotics may also lead to delirium, but no study has systemically compared delirium associations for many available antibiotics.

Objective

The objective of this study was to evaluate the association between delirium and antibiotics using the FDA Adverse Event Reporting System (FAERS).

Methods

FAERS reports from January 1, 2004 to December 31, 2018 were included in the study. Reporting odds ratios (RORs) and corresponding 95% confidence intervals (95% CI) for the association between antibiotics and delirium were calculated. An association was considered to be statistically significant when the lower limit of the 95% CI was greater than 1.0.

Results

A total of 10,015,622 reports (including 16,982 delirium reports) were considered, after inclusion criteria were applied. Statistically significant delirium RORs (95% CI) for antibiotics were: ertapenem 21.07 (16.38–27.10), cefepime 9.8 (6.37–15.09), imipenem 9.68 (6.75–13.89), ofloxacin 7.73 (4.00–14.92), ceftazidime 6.09 (2.73–13.62), clarithromycin 5.34 (4.37–6.53), cefaclor 5.32 (1.71–16.58), ampicillin–sulbactam 4.49 (2.13–9.45), levofloxacin 4.47 (3.88–5.16), linezolid 4.33 (3.28–5.72), moxifloxacin 3.51 (2.81–4.38), azithromycin 2.76 (2.09–3.64), piperacillin–tazobactam 2.41 (1.47–3.93), trimethoprim–sulfamethoxazole 2.36 (1.61–3.47), metronidazole 1.85 (1.31–2.60), ciprofloxacin 1.83 (1.44–2.33), and cefuroxime 1.81 (1.03–3.20).

Conclusion

This study found statistically significant increased risk of reporting delirium with ertapenem, cefepime, imipenem, ofloxacin, ceftazidime, clarithromycin, cefaclor, ampicillin–sulbactam, levofloxacin, linezolid, moxifloxacin, azithromycin, piperacillin–tazobactam, trimethoprim–sulfamethoxazole, metronidazole, ciprofloxacin, and cefuroxime.

Brief Overview of Approaches and Challenges in New Antibiotic Development: A Focus On Drug Repurposing

Drug repurposing, or identifying new uses for existing drugs, has emerged as an alternative to traditional drug discovery processes involving de novo synthesis. Drugs that are currently approved or under development for non-antibiotic indications may possess antibiotic properties, and therefore may have repurposing potential, either alone or in combination with an antibiotic. They might also serve as "antibiotic adjuvants" to enhance the activity of certain antibiotics.

MiR-130a regulating the biological function of colon cancer by targeting inhibition of PTEN

OBJECTIVE

To investigate the expression of miR-130a in human colon cancer patients and its specific mechanism of regulating the biological function of colon cancer cells.

PATIENTS AND METHODS

Cancer tissues, paracancerous tissues, and serum samples of 40 colon cancer patients who underwent surgery in The Second Affiliated Hospital of Qiqihar Medical University from May 2018 to March 2019 were collected, and 40 healthy volunteers who received physical examination in The Second Affiliated Hospital of Qiqihar Medical University were collected. Real Time-quantitative Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of miR-130a. Human colon cancer cell was divided into miR-130a mimic group, miR-130a inhibitor group, mimic NC (negative control), and inhibitor NC group. QRT-PCR was used to detect the expression of miR-130a, and MTT assay, colony formation assay, cell scratch assay, transwell assay were performed to detect cell viability, proliferation, migration, and invasion ability.

RESULTS

Compared with adjacent tissues, the expression of miR-130a was significantly increased in colon cancer tissues (p=0.0125); the expression of miR-130a in transfected miR-130a mimic group was higher than that in NC group, but the expression in transfected miR-130a inhibitor group was significantly lower than that in NC group; overexpression of miR-130a significantly increased cell viability, proliferation, migration, and invasion of colon cancer cells, while knockdown of miR-130a significantly inhibited colon cancer cell biological activity; target prediction, qRT-PCR, and Western blot assays showed that miR-130a participated in the development and progression of colon cancer by targeting inhibition of PTEN expression.

CONCLUSIONS

The expression of miR-130a in serum and cancer tissues of colon cancer patients is significantly increased, and it can regulate the biological function of colon cancer cells by inhibiting the expression of target gene PTEN. Knockdown of miR-130a may be used as a new clinical treatment for colon cancer.

Outcomes in chronic lymphocytic leukemia patients on novel agents in the US Veterans Health Administration System

The US veteran population has a high proportion of chronic lymphocytic leukemia (CLL) risk factors. Using the Veterans Health Administration (VHA) population, we conducted a retrospective chart review of 1205 CLL patients who initiated treatment with a novel oral agent. For 1L ibrutinib, 33% (n = 107) discontinued therapy during the study, of which 64% discontinued due to adverse events (AEs). For relapsed/refractory (R/R) ibrutinib, 35% (n = 262) discontinued therapy, of which 63% discontinued due to AEs. For R/R venetoclax, 31% (n = 27) discontinued therapy, of which 41% were due to AEs. For idelalisib, 84% (n = 41) discontinued therapy, of which 54% were due to AEs. This real-world study suggests that AEs play an important role in dose reductions and discontinuations; however, physician inexperience in using these drugs when they were first introduced could be part of what is leading to these negative outcomes.

Adverse event clusters present at dose-reduction in CLL patients on ibrutinib in the U.S. Veterans Health Administration

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Background: Previously, we reported that adverse events (AEs) were the top reason for dose reductions in VHA patients on novel agents. Some AEs might be problematic but might not directly lead to dose reduction; however, these concomitant AEs should not be overlooked. This study describes AE clusters that occurred with the primary AE that led to dose reduction in VHA CLL patients receiving ibrutinib. Methods: This is a retrospective chart review study of CLL patients treated with ibrutinib in the VHA from October 2013 to March 2018. Variables included the presence of dose reduction, the reasons for dose reduction, primary AEs leading to dose reduction, and concomitant AEs present at the time of dose reduction. Descriptive statistics were used to summarize AE clusters. Results: Out of 1069 CLL patients on ibrutinib, 285 patients experienced dose reduction due to AEs and were included in this analysis. The most common AEs leading to dose reduction were: musculoskeletal (11%), bleeding (11%), fatigue (10%), infection (9%), atrial fibrillation (8%), diarrhea (8%), and rash (8%). Fatigue was the leading concomitant AE present at dose reduction among patients who were dose reduced due to musculoskeletal (18%), infection (12%), diarrhea (18%), and rash (25%). Fatigue was also the second-leading or third leading concomitant AE among those who were dose reduced due to atrial fibrillation (13%) or bleeding (10%). Musculoskeletal was the leading or second-leading concomitant AE present at dose reduction among those who were dose reduced due to fatigue (17%), infection (12%), or diarrhea (14%). Bleeding was the leading concomitant AE among those who were dose reduced due to atrial fibrillation (17%) and vice versa. Conclusions: This study provides evidence that fatigue and musculoskeletal AEs are problematic in CLL patients on ibrutinib in the VHA. These were not only among the most common primary AEs but also the leading concomitant AEs present at dose reduction. Although not directly leading to dose reduction, these ‘nuisance’ AEs can greatly affect quality of life among CLL patients and warrant more attention from clinicians. A better understanding of all AEs present at dose reduction may help clinicians better manage patients on novel agents. These data also highlight the unmet need for novel agents with a ‘cleaner’ safety profile.

The shift in therapies for the treatment of chronic lymphocytic leukemia (CLL) patients in the US Veterans Health Administration (VHA) from 2013-2018

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Background: The first novel agent for use in CLL was approved in 2014; however, the extent of novel agent uptake in the VHA is largely unknown. Objective: This study described the pharmacoepidemiology of three novel agents (ibrutinib, idelalisib, venetoclax), and traditional chemotherapies/chemoimmunotherapies (CT/CIT) in the VHA. Methods: This was a retrospective study of 26,879 adults with CLL in the VHA from 10/01/2013 to 5/31/2018. All were followed for at least 6 months. Data were extracted from the VHA electronic health record. Patients came from all 18 Veterans Integrated Service Networks, spanning all 50 states and US territories. Descriptive statistics were used to summarize baseline characteristics, CLL treatments, next therapies, and secondary complications. Results: A total of 3670 patients received at least one of 12 CLL therapies of interest. Patients had a median age of 69 years (47% were 65+ and 26% were 75+), a median age-adjusted Charlson comorbidity score of 6, and 6% had a history of exposure to Agent Orange. Ibrutinib accounted for 89% of the novel agent use. Ibrutinib use across all lines of therapy (LOTs) increased sevenfold over the study period (Table). Venetoclax (42%) and idelalisib (30%) were the most common therapies for the next LOT after ibrutinib. Across all LOTs, traditional CT/CIT use declined steadily over the study period. However, in fiscal year (FY) 2018, there were still 17% of patients receiving CT/CIT. Ibrutinib was the most common therapy for the next LOT in these patients (43–74%). Incidence of diffuse large B cell lymphoma post-index was 2–6 times higher in patients on CT/CIT than those on ibrutinib. Other secondary complications were similar between ibrutinib and CT/CIT. Conclusions: To our knowledge, this is the largest study looking at CLL treatment patterns among VHA patients in the real world. There has been a major shift in the treatment of CLL, with fast adoption of novel agents in the VHA from 2013 to 2018. The impact of this shift on healthcare resource use and cost burden in the VHA will need to be examined. [Table: see text]

Hypoglycemia Associated with Antibiotics Alone and in Combination with Sulfonylureas and Meglitinides: An Epidemiologic Surveillance Study of the FDA Adverse Event Reporting System (FAERS)

INTRODUCTION

Fluoroquinolones, clarithromycin, linezolid, tigecycline, cefditoren, doxycycline, and trimethoprim-sulfamethoxazole are known to be associated with hypoglycemia, but few studies have considered concomitant glucose-lowering medications.

OBJECTIVE

The objective of this study was to evaluate the association between hypoglycemia and antibiotics using the US Food and Drug Administration Adverse Event Reporting System (FAERS), while accounting for concomitant glucose-lowering medications including sulfonylureas and meglitinides.

METHODS

FAERS reports from 1 January 2004 to 31 December 2017 were included in the study. Reporting odds ratios (RORs) and corresponding 95% confidence intervals (CIs) for the association between antibiotics and hypoglycemia were calculated. An association was considered to be statistically significant when the lower limit of the 95% CI was > 1.0.

RESULTS

A total of 2,334,959 reports (including 18,466 hypoglycemia reports) were considered, after inclusion criteria were applied. Statistically significant hypoglycemia RORs (95% CI) for antibiotics were: cefditoren 14.03 (8.93-22.03), tigecycline 3.32 (1.95-5.65), clarithromycin 2.41 (1.89-3.08), ertapenem 2.07 (1.14-3.75), moxifloxacin 2.06 (1.59-2.65), levofloxacin 1.66 (1.37-2.01), and linezolid 1.54 (1.07-2.20). After adjusting for concomitant sulfonylureas and meglitinides, the following antibiotics were still significantly associated with hypoglycemia: cefditoren 14.25 (9.08-22.39), tigecycline 3.34 (1.96-5.68), ertapenem 1.93 (1.03-3.60), and clarithromycin 1.56 (1.15-2.11).

CONCLUSION

In many patients, antibiotics, including fluoroquinolones, are associated with hypoglycemia when they are also taking sulfonylureas or meglitinides. Cefditoren, tigecycline, ertapenem, and clarithromycin are associated with hypoglycemia even if not taken with sulfonylureas or meglitinides. The association between ertapenem and hypoglycemia has not been previously reported.

1977. Comparing Acute Kidney Injury Risk among Antibiotic Classes: A Study of the FDA Adverse Event Reporting System (FAERS)

Background

A recent article published in 2018 studied the FDA Adverse Event Reporting System (FAERS) and listed the most common medications associated with acute kidney injury (AKI) based on number of AKI reports. In regards to antibiotics, the study only ranked vancomycin, fluoroquinolones, penicillin combinations, and trimethoprim–sulfamethoxazole as having a significant association with AKI. The objective of this study was to evaluate those and additional antibiotic classes using FAERS, and to compare their risk associated with this adverse drug event.

Methods

FAERS reports from January 1, 2015 to December 31, 2017 were included in the study. The Medical Dictionary for Regulatory Activities (MedDRA) was used to identify AKI cases. Reporting Odds Ratios (RORs) and corresponding 95% confidence intervals (95% CI) for the association between antibiotics and AKI were calculated. An association was considered statistically significant when the lower limit of the 95% CI was greater than 1.0.

Results

A total of 2,042,801 reports (including 20,138 acute kidney injury reports) were considered, after inclusion criteria were applied. Colistin had the greatest proportion of AKI reports, representing 25% of all colistin reports. Acute kidney injury RORs (95% CI) for antibiotics were (in descending order): colistin 33.10 (21.24–51.56), aminoglycosides 17.41 (14.49–20.90), vancomycin 15.28 (13.82–16.90), trimethoprim-sulfamethoxazole 13.72 (11.94–15.76), penicillin combinations 7.95 (7.09–8.91), clindamycin 6.46 (5.18–8.04), cephalosporins 6.07 (5.23–7.05), daptomycin 6.07 (4.61–7.99), macrolides 3.60 (3.04–4.26), linezolid 3.48 (2.54–4.77), carbapenems 3.31 (2.58–4.25), metronidazole 2.55 (1.94–3.36), tetracyclines 1.73 (1.26–2.36), and fluoroquinolones 1.71 (1.49–1.97).

Conclusion

This study found 17 classes of antibiotics and combinations that were significantly associated with AKI compared with four antibiotics that were mentioned in a recently published article looking at drug-associated AKI. While this study confirmed previous literature of certain antibiotics associated with increased risk of AKI, it also compared antibiotics within classes and provided additional insight regarding which antibiotics had the highest associated risk of an AKI.

Disclosures

All authors: No reported disclosures.

2296. Hypoglycemia Risk with Antibiotics: An Epidemiologic Surveillance Study of the FDA Adverse Event Reporting System (FAERS)

Background

In July of 2018, the FDA published a drug safety warning for the potential risk of developing hypoglycemia with fluoroquinolones. Some studies have evaluated the potential risk of developing hypoglycemia with linezolid and tigecycline. A few case reports have also been published that report hypoglycemia from cefditoren, doxycycline, and trimethoprim-sulfamethoxazole use. Since data comparing various antibiotics and the risk of developing hypoglycemia is limited, the objective of this study was to evaluate the association between hypoglycemia and antibiotics using the FDA Adverse Event Reporting Systems (FAERS).

Methods

FAERS reports from January 1, 2004 to December 31, 2017 were included in the study. The Medical Dictionary for Regulatory Activities (MedDRA) was used to identify cases of hypoglycemia. Reporting odds ratios (RORs) and corresponding 95% confidence intervals (95% CI) for the association between antibiotics and hypoglycemia were calculated. An association was considered to be statistically significant when the lower limit of the 95% CI was greater than 1.0.

Results

A total of 2,334,959 reports (including 18,466 hypoglycemia reports) were considered, after inclusion criteria were applied. Cefditoren had the greatest proportion of hypoglycemia reports, representing 10% of all cefditoren reports. Statistically significant hypoglycemia RORs (95% CI) for antibiotics were: cefditoren 14.03 (8.93–22.03), tigecycline 3.32 (1.95–5.65), clarithromycin 2.41 (1.89–3.08), ertapenem 2.07 (1.14–3.75), moxifloxacin 2.06 (1.59–2.65), levofloxacin 1.66 (1.37–2.01), linezolid 1.54 (1.07–2.20).

Conclusion

Cefditoren, tigecycline, clarithromycin, ertapenem, moxifloxacin, levofloxacin, and linezolid were all significantly associated with hypoglycemia. The ertapenem association had not been reported in prior literature. Levofloxacin and moxifloxacin were the only fluoroquinolones significantly associated with hypoglycemia, even though the FDA drug safety warning was issued for all fluoroquinolones. Doxycycline and trimethoprim-sulfamethoxazole were not significantly associated with hypoglycemia, even though case reports have reported hypoglycemia with doxycycline and trimethoprim-sulfamethoxazole.

Disclosures

All authors: No reported disclosures.

Comparative-effectiveness of ceftaroline and daptomycin as first-line MRSA therapy for patients with sepsis admitted to hospitals in the United States Veterans Health Care System

Objectives: This study compared hospital readmission and mortality for patients with sepsis who received ceftaroline or daptomycin as first-line MRSA therapy.Methods: This retrospective comparative-effectiveness study included adults ≥18 years old hospitalized in the United States Veterans Health Care System with sepsis between 10/1/2010-9/30/2014, who received ceftaroline or daptomycin within 14 days of hospital admission as the first antibiotic effective against methicillin resistant Staphylococcus aureus (MRSA). Patients with pneumonia, and those who received both study drugs, were excluded. Baseline characteristics were compared using Chi-square, Fischer's exact, Student's t, and Wilcoxon Rank Sum tests. Patient outcomes were compared with multivariable logistic regression models.Results: 409 patients were included (ceftaroline = 67, daptomycin = 342). Ceftaroline patients were older, less likely to be Black, more likely to have diabetes with complications, and had higher Charlson comorbidity scores. Median (interquartile range) time from admission to drug initiation was 1 (0-1) day for ceftaroline and 1 (1-3) day for daptomycin (p = 0.01). Unadjusted hospital readmission rates for ceftaroline and daptomycin, respectively, were: 30-day (25%/37%, p = 0.06), 60-day (27%/44%, p = 0.008), and 90-day (28%/46%, p = 0.01). Unadjusted mortality rates were: in-hospital (7%/12%, p = 0.4), 30-day (3%/9%, p = 0.1), 60-day (6%/12%, p = 0.2), and 90-day (7%/15%, p = 0.1). In multivariable models with all divergent baseline characteristics included as covariates, patients treated with ceftaroline were less likely to experience (OR, 95% CI): 30/60/90-day hospital readmission (0.54, 0.29-0.98; 0.42, 0.23-0.76; 0.42, 0.23-0.75) and 30/60/90-day mortality (0.23, 0.04-0.82; 0.34, 0.10-0.93; 0.34, 0.11-0.86).Conclusion: In patients with sepsis, ceftaroline was associated with fewer hospital readmissions and lower mortality as compared to daptomycin. Prospective investigations in larger, more generalized cohorts are needed to examine outcomes with specific MRSA therapies.

Antipseudomonal monotherapy or combination therapy for older adults with community-onset pneumonia and multidrug-resistant risk factors: a retrospective cohort study

BACKGROUND

Infectious Diseases Society of America guidelines recommend empiric antipseudomonal combination therapy when Pseudomonas is suspected. However, combination antipseudomonal therapy is controversial. This study compares all-cause 30-day mortality in older patients who received antipseudomonal monotherapy (PMT) or antipseudomonal combination therapy (PCT) for the treatment of community-onset pneumonia.

METHODS

This population-based, retrospective cohort study used data from over 150 Veterans Health Administration hospitals. Patients were classified as being at low, medium, or high risk of drug-resistant pathogens. In total, 31,027 patients were assigned to PCT or PMT treatment arms based on antibiotics received in the first 48 hours of hospital admission.

RESULTS

The unadjusted 30-day mortality difference between PCT and PMT was most pronounced in the low-risk group (18% vs 8%), followed by the medium-risk group (24% vs 18%) and then the high-risk group (39% vs 33%). PCT was associated with higher 30-day mortality than PMT overall (adjusted odds ratio [aOR], 1.54; 95% confidence interval [CI], 1.43-1.66) in all 3 risk groups: low (aOR, 1.69; 95% CI, 1.50-1.89), medium (aOR, 1.30; 95% CI, 1.14-1.48), and high (aOR, 1.21; 95% CI, 1.04-1.40).

CONCLUSIONS

Older adults who received combination antipseudomonal therapy for community-onset pneumonia fared worse than those who received monotherapy. Empiric combination antipseudomonal therapy should not be routinely offered to all patients suspected of having pseudomonal pneumonia.

Clostridium difficile Infection Risk with Important Antibiotic Classes: An Analysis of the FDA Adverse Event Reporting System

Introduction: Antibiotic use is an important risk factor for Clostridium difficile infection (CDI). Prior meta-analyses have identified antibiotics and antibiotic classes that pose the greatest risk for CDI; however, CDI epidemiology is constantly changing and contemporary analyses are needed. Objectives: The objective of this study was to evaluate the association between CDI and important antibiotic classes in recent years using the FDA Adverse Event Report System (FAERS). Methods: FAERS reports from January 1, 2015 to December 31, 2017 were analyzed. The Medical Dictionary for Regulatory Activities (MedDRA) was used to identify CDI cases. We computed the Reporting Odds Ratios (RORs) and corresponding 95% confidence intervals (95%CI) for the association between antibiotics and CDI. An association was considered statistically significant when the lower limit of the 95%CI was greater than 1. Results: A total of 2,042,801 reports (including 5,187 CDI reports) were considered, after inclusion criteria were applied. Lincosamides (e.g., clindamycin) had the greatest proportion of CDI reports, representing 10.4% of all lincosamide reports. CDI RORs (95%CI) for the antibiotic classes were (in descending order): lincosamides 46.95 (39.49-55.82), monobactams 29.97 (14.60-61.54), penicillin combinations 20.05 (17.39-23.12), carbapenems 19.16 (15.52-23.67), cephalosporins/ monobactams/carbapenems 17.28 (14.95-19.97), cephalosporins 15.33 (12.60-18.65), tetracyclines 7.54 (5.42-10.50), macrolides 5.80 (4.48-7.51), fluoroquinolones 4.94 (4.20-5.81), and trimethoprim-sulfonamides 3.32 (2.03-5.43). Conclusion: All antibiotic classes included in the study were significantly associated with CDI. Lincosamides (e.g., clindamycin) had the highest CDI ROR among the antibiotics evaluated in this study.

Comparison of Quetiapine Abuse and Misuse Reports to the FDA Adverse Event Reporting System With Other Second-Generation Antipsychotics

BACKGROUND

Second-generation antipsychotics (SGAs) are assumed to have little abuse potential. However, reports of quetiapine abuse have emerged as prescribing has increased in recent years. The US Food and Drug Administration's (FDA) Adverse Event Reporting System (FAERS) provides postmarketing information regarding adverse drug events (ADEs). This is the first study to analyze quetiapine abuse-related ADEs reported to FAERS to determine whether a disproportionate rate of such events have been reported when compared with other commonly used SGAs.

METHODS

A cross-sectional analysis of FAERS data from January 1, 2015, to December 31, 2017, was performed. The total number of all-cause and abuse-related ADEs reported to FAERS regarding quetiapine, olanzapine, aripiprazole, and risperidone were identified, along with demographic and mortality data. The proportional reporting ratio (PRR) was calculated to assess disproportionate reporting of abuse-related adverse drug reactions between quetiapine and each of three alternative SGA medications.

RESULTS

Abuse-related ADEs represented 11% (3144/27 962) of total ADEs reported for quetiapine, 8% for olanzapine (1548/19 228), 5% (1380/29 699) for aripiprazole, and 3% (1168/45 518) for risperidone. The PRRs (95% confidence interval) for quetiapine versus olanzapine, aripiprazole, and risperidone were 1.40 (1.32-1.48), 2.42 (2.28-2.57), and 4.38 (4.10-4.68), respectively, indicating that abuse-related events were significantly more likely to be reported with quetiapine than each comparator drug. In addition, more deaths were reported among the abuse-related events regarding quetiapine (673) than olanzapine (200), aripiprazole (88), and risperidone (143).

CONCLUSION

This study corroborates recent evidence indicating that quetiapine might possess a significantly higher abuse potential than other commonly used SGAs. Although prospective studies are needed to better understand the abuse potential of quetiapine, increased vigilance in monitoring for signs of substance abuse might be warranted when prescribing quetiapine.

Torsades de pointes and QT prolongation Associations with Antibiotics: A Pharmacovigilance Study of the FDA Adverse Event Reporting System

Introduction: Macrolides, linezolid, imipenem-cilastatin, fluoroquinolones, penicillin combinations, and ceftriaxone are known to be associated with Torsades de pointes/QT prolongation (TdP/QTP). Other antibiotics may also lead to TdP/QTP, but no study has systemically compared TdP/QTP associations for many available antibiotics. Objectives: The objective of this study was to evaluate the association between TdP/QTP and many available antibiotics using the FDA Adverse Event Report System (FAERS). Methods: FAERS reports from January 1, 2015 to December 31, 2017 were analyzed. The Medical Dictionary for Regulatory Activities (MedDRA) was used to identify TdP/QTP cases. We calculated the Reporting Odds Ratios (RORs) and corresponding 95% confidence intervals (95%CI) for the association between antibiotics and TdP/QTP. An association was considered to be statistically significant when the lower limit of the 95%CI was greater than 1.0. Results: A total of 2,042,801 reports (including 3,960 TdP/QTP reports) were considered, after inclusion criteria were applied. Macrolides had the greatest proportion of TdP/QTP reports. Of the 4,092 reports associated with macrolides, 108 reports (2.6%) were associated with TdP/QTP. Significant TdP/QTP RORs (95%CI) for the antibiotics were (in descending order): macrolides 14.32 (11.80-17.38), linezolid 12.41 (8.52-18.08), amikacin 11.80 (5.57-24.97), imipenem-cilastatin 6.61 (3.13-13.94), fluoroquinolones 5.68 (4.78-6.76), penicillin combinations 3.42 (2.35-4.96), and ceftriaxone 2.55 (1.41-4.62). Conclusion: This study confirms prior evidence for TdP/QTP associations with macrolides, linezolid, imipenem-cilastatin, fluoroquinolones, penicillin combinations, and ceftriaxone. This study also identifies a new association between amikacin and TdP/QTP.

Rhabdomyolysis Associations with Antibiotics: A Pharmacovigilance Study of the FDA Adverse Event Reporting System (FAERS)

Introduction: Daptomycin, macrolides, trimethoprim-sulfamethoxazole, linezolid, fluoroquinolones, and cefdinir are known to be associated with rhabdomyolysis. Other antibiotics may also lead to rhabdomyolysis, but no study has systemically compared rhabdomyolysis associations for many available antibiotics. Objectives: The objective of this study was to evaluate the association between rhabdomyolysis and many available antibiotics using the FDA Adverse Event Report System (FAERS). Methods: FAERS reports from January 1, 2004 to December 31, 2017 were included in the study. The Medical Dictionary for Regulatory Activities (MedDRA) was used to identify rhabdomyolysis cases. Reporting Odds Ratios (RORs) and corresponding 95% confidence intervals (95%CI) for the association between antibiotics and rhabdomyolysis were calculated. An association was considered statistically significant when the lower limit of the 95%CI was greater than 1.0. Results: A total of 2,334,959 reports (including 7,685 rhabdomyolysis reports) were considered, after inclusion criteria were applied. Daptomycin had the greatest proportion of rhabdomyolysis reports, representing 5.5% of all daptomycin reports. Statistically significant rhabdomyolysis RORs (95% CI) for antibiotics were (in descending order): daptomycin 17.94 (14.08-22.85), cefditoren 8.61 (3.54-20.94), cefaclor 7.16 (2.28-22.49), erythromycin 5.93 (3.17-11.10), norfloxacin 4.50 (1.44-14.07), clarithromycin 3.95 (2.77-5.64), meropenem 3.19 (1.51-6.72), azithromycin 2.94 (1.96-4.39), cefdinir 2.84 (1.06-7.62), piperacillin-tazobactam 2.61 (1.48-4.61), trimethoprim-sulfamethoxazole 2.53 (1.52-4.21), linezolid 2.49 (1.47-4.21), ciprofloxacin 2.10 (1.51-2.92). Conclusions: This study confirms prior evidence for rhabdomyolysis associations with daptomycin, macrolides, trimethoprim-sulfamethoxazole, linezolid, fluoroquinolones, and cefdinir. This study also identifies previously unknown rhabdomyolysis associations with meropenem, cefditoren, cefaclor, and piperacillin-tazobactam.

2172. Assessment of Cefepime Neurotoxicity in the FDA Adverse Reporting System

Background

Methods

Results

Conclusion

Disclosures

1881. Empiric Pseudomonal Monotherapy vs. Combination Therapy for Community-Onset Pneumonia in Older Adults

Background

Patients with pseudomonal pneumonia have a poor prognosis; therefore, IDSA guidelines recommend empiric antipseudomonal combination therapy when Pseudomonas is suspected, at least until treatment can be adjusted based on susceptibilities. However, combination antipseudomonal therapy is controversial. This study compared all-cause 30-day mortality in older patients who received antipseudomonal monotherapy (PMT) or antipseudomonal combination therapy (PCT) for the treatment of community-onset pneumonia.

Methods

This population-based cohort study used data from over 150 Veteran Health Administration hospitals. Patients were classified as low, medium, or high risk of drug-resistant pathogens according to a published rule. Patients were assigned to PCT or PMT groups based on antibiotics received in the first 48 hours of hospital admission. Separate multivariable logistic regression models were constructed to determine whether the choice of PCT or PMT was associated with 30-day mortality, after accounting for divergent baseline characteristics. Adjusted odds ratios (aORs) and 95% confidence intervals (95% CI) were calculated for the overall, low, medium, and high-risk groups.

Results

Of the 31,027 patients who met study criteria, 23% received PCT and 77% received PMT. Patients belonged to low (59%), medium (24%), and high (18%) risk groups. 30-day mortality was 18% overall, and increased among the groups: low (13%), medium (21%), and high (36%). Patient age (median of 78 years), race (>80% white), and sex (>98% male) were similar for patients receiving PCT and PMT. The unadjusted mortality difference between PCT and PMT was most pronounced in the low-risk group (18% vs. 8%, 10% absolute risk difference), followed by the medium (24% vs. 18%, 6% difference) and high (39% vs. 33%, 6% difference) risk groups. PCT was associated with higher 30-day mortality than PMT overall (aOR, 1.54; 95% CI, 1.43–1.66), and in all three groups: low (aOR, 1.69; 95% CI, 1.50–1.89), medium (aOR, 1.30; 95% CI, 1.14–1.48), and high (aOR, 1.21; 95% CI, 1.04–1.40).

Conclusion

Older adults who received empiric combination antipseudomonal therapy for community-onset pneumonia fared worse than those who received monotherapy. Empiric combination antipseudomonal therapy should not be routinely offered to all patients suspected of having pseudomonal pneumonia.

Disclosures

All authors: No reported disclosures.

Ubiquitin Receptor RPN13 Mediates the Inhibitory Interaction of Diphenyldihaloketones CLEFMA and EF24 With the 26S Proteasome

The proteasome is a validated target in drug discovery for diseases associated with unusual proteasomal activity. Here we report that two diphenyldihaloketones, CLEFMA and EF24, inhibit the peptidase activity of the 26S proteasome. The objective of this study was to investigate interaction of these compounds with the proteasome and identify a putative target within the protein components of the 26S proteasome. We employed standard fluorogenic peptide-based proteasome activity assay for trypsin-like, chymotrypsin-like, and caspase-like activities of human purified 26S proteasome in cell-free conditions. GFPu-1 and HUVEC cells were used as proteasome reporter cells. Direct binding studies used purified 19S, 20S, 26S, and recombinant RPN13-Pru for interaction with biotinylated analogs of CLEFMA and EF24. The reaction mixtures were subjected to horizontal gel electrophoresis, streptavidin-blotting, pull-down assays, and immunoblotting. The identity of the interacting protein was determined by 2D gel electrophoresis and LC-MS/MS. Drug affinity responsive target stability technique was utilized to examine if CLEFMA binding confers protection to RPN13 against thermolysin-catalyzed proteolysis. We found that trypsin-and chymotrypsin-like activities of the 26S proteasome were reduced significantly by both compounds. The compounds also reduced the proteolytic activity in GFPu-1 and HUVEC cells, resulting in accumulation of ubiquitinated proteins without affecting the autophagy process. From direct binding assays a 43 kDa protein in the 26S proteasome was found to be the interacting partner. This protein was identified by tandem mass spectroscopy as regulatory particle subunit 13 (RPN13), a ubiquitin receptor in the 19S regulatory particle. Furthermore, binding of CLEFMA to RPN13 did not protect latter from thermolysin-mediated proteolysis. Together, this study showed diphenyldihaloketones as potential proteasome inhibitors for treatment of diseases with perturbed proteasome function. The results also unraveled RPN13 as a unique target of CLEFMA and EF24. As a result, these compounds inhibit both trypsin-like and chymotrypsin-like proteasome activities.

Induction of gut proteasome activity in hemorrhagic shock and its recovery by treatment with diphenyldihaloketones CLEFMA and EF24

Multiorgan failure in hemorrhagic shock is triggered by gut barrier dysfunction and consequent systemic infiltration of proinflammatory factors. Our previous study has shown that diphenyldihaloketone drugs 4-[3,5-bis[(2-chlorophenyl)methylene]-4-oxo-1-piperidinyl]-4-oxo-2-butenoic acid (CLEFMA) and 3,5-bis[(2-fluorophenyl)methylene]-4-piperidinone (EF24) restore gut barrier dysfunction and reduce systemic inflammatory response in hemorrhagic shock. We investigated the effect of hemorrhagic shock on proteasome activity of intestinal epithelium and how CLEFMA and EF24 treatments modulate proteasome function in hemorrhagic shock. CLEFMA or EF24 (0.4 mg/kg) were given 1 h after withdrawing 50% of blood from Sprague-Dawley rats; no other resuscitation was provided. After another 5 h of compensation, small gut was collected to process tissue for proteasome activity, immunoblotting, and mRNA levels of genes responsible for unfolded-protein response (XBP1, ATF4, glucose-regulated protein of 78/95 kDa, and growth arrest and DNA damage inducible genes 153/34), polyubiquitin B and C, and immunoproteasome subunits β type-8 and -10 and proteasome activator subunit 1. We found that hemorrhagic shock induced proteasome activity in gut tissue and reduced the amounts of ubiquitinated proteins displayed on antiubiquitin immunoblots. However, simultaneous induction of unfolded-protein response or immunoproteasome genes was not observed. CLEFMA and EF24 treatments abolished the hemorrhagic shock-induced increase in proteasome activity. Further investigations revealed that the induction of proteasome in hemorrhagic shock is associated with disassembly of 26S proteasome; CLEFMA and EF24 prevented this disassembly. Consistent with these data, CLEFMA and EF24 reduced hemorrhagic shock-induced degradation of 20S substrate ornithine decarboxylase in gut tissue. These results suggest that activated proteasome plays an important role in ischemic gut pathophysiology, and it can be a druggable target in shock-induced gut dysfunction. NEW & NOTEWORTHY Ischemic injury to the gut is a trigger for the systemic inflammatory response and multiple organ failure in trauma and hemorrhagic shock. We show for the first time that hemorrhagic shock induces the gut proteasome activity by engendering 26S proteasome disassembly. Diphenyldihaloketones 4-[3,5-bis[(2-chlorophenyl)methylene]-4-oxo-1-piperidinyl]-4-oxo-2-butenoic acid and 3,5-bis[(2-fluorophenyl)methylene]-4-piperidinone treatment prevented the 26S disassembly. Understanding the role of proteasome in shock-associated gut injury will assist in the development of therapeutic means to address it.

Learning from other people's fear: amygdala-based social reference learning in social anxiety disorder

BACKGROUND

Social anxiety disorder involves fear of social objects or situations. Social referencing may play an important role in the acquisition of this fear and could be a key determinant in future biomarkers and treatment pathways. However, the neural underpinnings mediating such learning in social anxiety are unknown. Using event-related functional magnetic resonance imaging, we examined social reference learning in social anxiety disorder. Specifically, would patients with the disorder show increased amygdala activity during social reference learning, and further, following social reference learning, show particularly increased response to objects associated with other people's negative reactions?

METHOD

A total of 32 unmedicated patients with social anxiety disorder and 22 age-, intelligence quotient- and gender-matched healthy individuals responded to objects that had become associated with others' fearful, angry, happy or neutral reactions.

RESULTS

During the social reference learning phase, a significant group × social context interaction revealed that, relative to the comparison group, the social anxiety group showed a significantly greater response in the amygdala, as well as rostral, dorsomedial and lateral frontal and parietal cortices during the social, relative to non-social, referencing trials. In addition, during the object test phase, relative to the comparison group, the social anxiety group showed increased bilateral amygdala activation to objects associated with others' fearful reactions, and a trend towards decreased amygdala activation to objects associated with others' happy and neutral reactions.

CONCLUSIONS

These results suggest perturbed observational learning in social anxiety disorder. In addition, they further implicate the amygdala and dorsomedial prefrontal cortex in the disorder, and underscore their importance in future biomarker developments.

Implementation hurdles of an interactive, integrated, point-of-care computerised decision support system for hospital antibiotic prescription

Antimicrobial stewardship is used to combat antimicrobial resistance. In Singapore, a tertiary hospital has integrated a computerised decision support system, called Antibiotic Resistance Utilisation and Surveillance-Control (ARUSC), into the electronic inpatient prescribing system. ARUSC is launched either by the physician to seek guidance for an infectious disease condition or via auto-trigger when restricted antibiotics are prescribed. This paper describes the implementation of ARUSC over three phases from 1 May 2011 to 30 April 2013, compared factors between ARUSC launches via auto-trigger and for guidance, examined factors associated with acceptance of ARUSC recommendations, and assessed user acceptability. During the study period, a monthly average of 9072 antibiotic prescriptions was made, of which 2370 (26.1%) involved ARUSC launches. Launches via auto-trigger comprised 48.1% of ARUSC launches. In phase 1, 23% of ARUSC launches were completed. This rose to 38% in phase 2, then 87% in phase 3, as escapes from the ARUSC programme were sequentially disabled. Amongst completed launches for guidance, 89% of ARUSC recommendations were accepted versus 40% amongst completed launches via auto-trigger. Amongst ARUSC launches for guidance, being from a medical department [adjusted odds ratio (aOR)=1.20, 95% confidence interval (CI) 1.04-1.37] and ARUSC launch during on-call (aOR=1.81, 95% CI 1.61-2.05) were independently associated with acceptance of ARUSC recommendations. Junior physicians found ARUSC useful. Senior physicians found ARUSC reliable but admitted to having preferences for antibiotics that may conflict with ARUSC. Hospital-wide implementation of ARUSC encountered hurdles from physicians. With modifications, the completion rate improved.

Ubiquitin-Proteasome System in Neurodegenerative Disorders

Cellular proteostasis is a highly dynamic process and is primarily carried out by the degradation tools of ubiquitin-proteasome system (UPS). Abnormalities in UPS function result in the accumulation of damaged or misfolded proteins which can form intra- and extracellular aggregated proteinaceous deposits leading to cellular dysfunction and/or death. Deposition of abnormal protein aggregates and the cellular inability to clear them have been implicated in the pathogenesis of a number of neurodegenerative disorders such as Alzheimer's and Parkinson's. Contrary to the upregulation of proteasome function in oncogenesis and the use of proteasome inhibition as a therapeutic strategy, activation of proteasome function would serve therapeutic objectives of treatment of neurodegenerative diseases. This review describes the current understanding of the role of the proteasome in neurodegenerative disorders and potential utility of proteasomal modulation therein.

Mouse embryonic stem cells have underdeveloped antiviral mechanisms that can be exploited for the development of mRNA-mediated gene expression strategy

We have recently reported that mouse embryonic stem cells (mESCs) are deficient in expressing type I interferons (IFN) when exposed to viral infection and double-stranded RNA. In this study, we extended our investigation and demonstrated that single-stranded RNA and protein-encoding mRNA can induce strong IFN expression and cytotoxicity in fibroblasts and epithelial cells, but none of the effects associated with these antiviral responses were observed in mESCs. Our results provided additional data to support the conclusion that mESCs are intrinsically deficient in antiviral responses. While our findings represent a novel feature of mESCs that in itself is important for understanding innate immunity development, we exploited this property to develop a novel mRNA-mediated gene expression cell model. Direct introduction of synthetic mRNA to express desired genes has been shown as an effective alternative to DNA/viral vector-based gene expression. However, a major biological challenge is that a synthetic mRNA is detected as a viral RNA analog by the host cell, resulting in a series of adverse effects associated with antiviral responses. We demonstrate that the lack of antiviral responses in mESCs effectively avoids this problem. mESCs can tolerate repeated transfection and effectively express proteins from their synthetic mRNA with expected biological functions, as demonstrated by the expression of green fluorescent protein and the transcription factor Etv2. Therefore, mRNA-based gene expression could be developed into a novel ESC differentiation strategy that avoids safety concerns associated with viral/DNA-based vectors in regenerative medicine.

Guanidine-Containing Methacrylamide (Co)polymers via aRAFT: Toward a Cell Penetrating Peptide Mimic()

We report the synthesis and controlled radical homo- and block copolymerization of 3-guanidinopropyl methacrylamide (GPMA) utilizing aqueous reversible addition-fragmentation chain transfer (aRAFT) polymerization. The resulting homopolymer and block copolymer with N-(2-hydroxypropyl) methacrylamide (HPMA) were prepared to mimic the behavior of cell penetrating peptides (CPPs) and poly(arginine) (> 6 units) which have been shown to cross cell membranes. The homopolymerization mediated by 4-cyano-4-(ethylsulfanylthiocarbonylsulfanyl)pentanoic acid (CEP) in aqueous buffer exhibited pseudo-first-order kinetics and linear growth of molecular weight with conversion. Retention of the "living" thiocarbonylthio ω-end-group was demonstrated through successful chain extension of the GPMA macroCTA yielding GPMA(37)-b-GPMA(61) (M(w)/M(n) =1.05). Block copolymers of GPMA with the non-immunogenic, biocompatible HPMA were synthesized yielding HPMA(271)-b-GPMA(13) (M(w)/M(n) = 1.15). Notably, intracellular uptake was confirmed by fluorescence microscopy, confocal laser scanning microscopy, and flow cytometry experiments after 2.5 h incubation with KB cells at 4 °C and at 37 °C utilizing FITC-labeled, GPMA-containing copolymers. The observed facility of cellular uptake and the structural control afforded by aRAFT polymerization suggest significant potential for these synthetic (co)polymers as drug delivery vehicles in targeted therapies.

Non-Linear Optical Polymers for Active Optical Devices

Second order non-linear optical (NLO) polymers have been the focus of intense research effort in recent years [1]. This effort is justified by the potential value of these materials in a range of attractive optical signal processing applications with lower device costs and enhanced device performance.

Virus-triggered ubiquitination of TRAF3/6 by cIAP1/2 is essential for induction of interferon-beta (IFN-beta) and cellular antiviral response

Viral infection causes activation of transcription factors NF-kappaB and IRF3, which collaborate to induce type I interferons (IFNs) and cellular antiviral response. Here we show that knockdown of the E3 ubiquitin ligases cIAP1 and cIAP2 markedly inhibited virus-triggered activation of IRF3 and NF-kappaB as well as IFN-beta induction. Knockdown of cIAP1 and cIAP2 also inhibited cytoplasmic dsRNA-triggered cellular antiviral response. Endogenous coimmunoprecipitation experiments indicated that viral infection caused recruitment of cIAP1 and cIAP2 to TRAF3, TRAF6, and VISA. Furthermore, we demonstrated that cIAP1- and cIAP2-mediated virus-triggered ubiquitination of TRAF3 and TRAF6. These findings suggest that virus-triggered ubiquitination of TRAF3 and TRAF6 by cIAP1 and cIAP2 is essential for type I IFN induction and cellular antiviral response.

Effect of a tight necktie on intraocular pressure

AIM

To evaluate the effect of a tight necktie on intraocular pressure (IOP) measurement using Goldmann applanation tonometry.

METHODS

40 eyes of 20 normal subjects and 20 open angle glaucoma patients (all male) were enrolled. IOP was measured with an open shirt collar, 3 minutes after placing a tight necktie, and 3 minutes after loosening it. All measurements were made by the same examiner.

RESULTS

Mean IOP in normal subjects increased by 2.6 (SD 3.9) mm Hg (p=0.008, paired t test; range -3 to +14 mm Hg) and in glaucoma patients by 1.0 (1.8) mm Hg (p=0.02, paired t test; range -2 to +4.5 mm Hg). In normal subjects, IOP in 12 eyes was increased by >/=2 mm Hg and in seven eyes by >/=4 mm Hg. In glaucoma patients, IOP in six eyes was increased by >/=2 mm Hg and in two eyes by >/=4 mm Hg.

CONCLUSION

A tight necktie increases IOP in both normal subjects and glaucoma patients and could affect the diagnosis and management of glaucoma.

Umbilical threonine uptake during maternal threonine infusion in sheep

OBJECTIVE

The infusion into the maternal circulation of amino acid solutions failed to increase umbilical threonine (THR) uptake above normal even when THR was present in the infusate at a relatively high concentration. The purpose of the present study was to determine whether umbilical THR uptake can be increased by infusing a THR solution that does not contain any other amino acids.

STUDY DESIGN

Five pregnant sheep (130+/-1.0 days after conception) were infused for 2h with a threonine solution (4.4+/-0.2 micromol.kg(-1).min(-1)). Plasma amino acids, glucose and lactate, hematocrit, blood O(2) content in maternal arterial, uterine venous, umbilical arterial and venous blood were measured. Uterine and umbilical blood flows were measured before and during the infusion and were used to calculate uterine and umbilical uptakes. Maternal and foetal plasma insulin and glucagon concentrations were also measured.

RESULTS

The THR infusion increased maternal plasma THR (904 vs 236 microM, P< 0.001), foetal plasma THR (539 vs 334 microM, P< 0.01), and both uterine (20.4 vs 4.7 micromol.min(-1).kg(-1)(fetalweight), P< 0.05) and umbilical (8.6 vs 3.8 micromol.min(-1).kg(-1)(fetalweight), P< 0.001) THR uptakes. The uterine-umbilical THR uptake difference increased significantly (11.8 vs 0.9 micromol.min(-1).kg(-1)(fetalweight), P< 0.05). There were significant (P< 0.001) decreases in the foetal arterial plasma concentrations of tyrosine and the branched chain amino acids, as well as in isoleucine umbilical uptake (P< 0.05). There was a significant increase in maternal plasma glucagon (P< 0.01).

CONCLUSION

A maternal THR infusion that causes a 3.8-fold increase in maternal plasma THR concentration above normal, with no significant increase in the concentration of other amino acids, leads to a 2.3-fold increase in umbilical THR uptake. This contrasts with the absence of a significant increase in umbilical THR uptake when THR was infused as part of an amino acid mixture in previous studies. The evidence supports the hypothesis that, in vivo, THR flux from placenta to foetus is mediated by a saturable, rate limiting transport system which is subject to inhibition by other neutral amino acids.

Effects of branched-chain amino acids on placental amino acid transfer and insulin and glucagon release in the ovine fetus

OBJECTIVE

Competition for placental amino acid transporters can affect the fetal supply of amino acids. Specifically, the branched-chain amino acids-isoleucine, leucine, and valine-may inhibit the transfer of other amino acids. This study was undertaken to determine the effect of branched-chain amino acids on the umbilical uptake of amino acids.

STUDY DESIGN

Six late-gestation ewes were infused sequentially for 2 hours with 3 different mixtures of amino acids: (1) one that was comparable to commercial parenteral nutrition preparations, (2) the same solution without branched-chain amino acids, and (3) branched-chain amino acids alone. Maternal and fetal blood samples were collected simultaneously for the determination of uterine and umbilical uptake values of amino acids, and for concentrations of arterial insulin, glucagon, glucose, and lactate before (control) and during (experimental) infusion.

RESULTS

Umbilical uptake of branched-chain amino acids increased significantly when they were present in the infusates. The fetal uptake of several other amino acids could be increased by increasing their maternal concentrations. Inhibition of umbilical uptake by branched-chain amino acids could be shown for threonine and methionine. The infusion of branched-chain amino acids alone did not affect maternal and fetal insulin or glucagon concentrations.

CONCLUSIONS

In late-gestation sheep, an increase in maternal plasma concentration of branched-chain amino acids led to increased branched-chain amino acid umbilical uptake, but branched-chain amino acids can also inhibit the transport of some amino acids to the fetus. Changes in fetal plasma concentration and uptake of branched-chain amino acid appear to have no significant effect on fetal insulin or glucagon.

Broussochalcone A, a potent antioxidant and effective suppressor of inducible nitric oxide synthase in lipopolysaccharide-activated macrophages

The antioxidant properties of broussochalcone A (BCA) and its effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated macrophages were investigated in this study. BCA, isolated from Broussonetia papyrifera Vent., inhibited iron-induced lipid peroxidation in rat brain homogenate in a concentration-dependent manner with an IC(50) of 0.63 +/- 0.03 microM. It was as potent as butylated hydroxytoluene, a common antioxidant used for food preservation. In a diphenyl-2-picrylhydrazyl assay system, the radical-scavenging activity of BCA seemed to be more potent than that of alpha-tocopherol, its IC(0.200) being 7.6 +/- 0.8 microM. BCA could directly scavenge superoxide anion and hydroxyl radicals. These results indicated that BCA was a powerful antioxidant with versatile free radical-scavenging activity. On the other hand, we found that BCA suppressed NO production concentration-dependently, with an IC(50) of 11.3 microM in LPS-activated macrophages. This effect was not the consequence of a direct inhibitory action on the enzyme activity of inducible NO synthase (iNOS). Our results indicated that BCA exerts potent inhibitory effects on NO production, apparently mediated by its suppression of IkappaBalpha phosphorylation, IkappaBalpha degradation, nuclear factor-kappa B activation, and iNOS expression. Therefore, we conclude that the antioxidant activities of BCA and its inhibition of IkappaBalpha degradation and iNOS protein expression may have therapeutic potential, given that excessive free radicals and NO production have been associated with various inflammatory diseases.