Effect of Repeated Exposure to Sevoflurane on Electroencephalographic Alpha Oscillation in Pediatric Patients Undergoing Radiation Therapy: A Prospective Observational Study

BACKGROUND

Pharmacological tolerance is defined as a decrease in the effect of a drug over time, or the need to increase the dose to achieve the same effect. It has not been established whether repeated exposure to sevoflurane induces tolerance in children.

METHODS

We conducted an observational study in children younger than 6 years of age scheduled for multiple radiotherapy sessions with sevoflurane anesthesia. To evaluate the development of sevoflurane tolerance, we analyzed changes in electroencephalographic spectral power at induction, across sessions. We fitted individual and group-level linear regression models to evaluate the correlation between the outcomes and sessions. In addition, a linear mixed-effect model was used to evaluate the association between radiotherapy sessions and outcomes.

RESULTS

Eighteen children were included and the median number of radiotherapy sessions per child was 28 (interquartile range: 10 to 33). There was no correlation between induction time and radiotherapy sessions. At the group level, the linear mixed-effect model showed, in a subgroup of patients, that alpha relative power and spectral edge frequency 95 were inversely correlated with the number of anesthesia sessions. Nonetheless, this subgroup did not differ from the other subjects in terms of age, sex, or the total number of radiotherapy sessions.

CONCLUSIONS

Our results suggest that children undergoing repeated anesthesia exposure for radiotherapy do not develop tolerance to sevoflurane. However, we found that a group of patients exhibited a reduction in the alpha relative power as a function of anesthetic exposure. These results may have implications that justify further studies.

Percutaneous Balloon Compression for the Treatment of Trigeminal Neuralgia: A Review of 10 Years of Clinical Experience

BACKGROUND

Trigeminal neuralgia (TN) is defined as a spontaneous painful sensation in the trigeminal nerve territory. The pain intensity of TN is classified into different grades of suffering that affect a patient's quality of life. Percutaneous balloon compression of the ganglion is a neurosurgical option that is easy, reproducible, and can reduce the morbidity of TN.

METHODS

We retrospectively analyzed all patients treated with trigeminal nerve percutaneous balloon compression at the Clinical Hospital of the University of Chile between January 2012 and May 2022. Data collected from electronic records included demographic information, medical and surgical history, type of anesthesia and drugs used during surgery, balloon inflation time, surgery time, operative room time, intraoperative events, postoperative complications, duration of hospitalization, and duration of follow-up.  Results: We identified 63 patients who met our inclusion criteria. The median patient age was 62 years (interquartile range [IQR] 57-69 years). Sixty-five percent of the patients were female. The simultaneous involvement of the second and third branches of the trigeminal nerve was the most frequent symptom. Before surgery, the patients experienced an average of 6.6 years of pain (IQR 2-10 years). Right neuralgia was the most frequent laterality type (69%). Forty percent of the patients had a previous surgical procedure for neuralgia, with treatment failure being the most frequent surgical indication (63%). According to the procedure, the mean balloon insufflation volume was 0.89±0.12 mL with a median compression time of 2.5 min (IQR 2.1-4.0 min). No hemorrhagic complications were observed. Furthermore, during follow-up, there were no surgical complications among any of the patients; however, 6.4% of patients required a second intervention. The pain-free period was two years in 60% of patients and five years in 23% of patients.

CONCLUSIONS

TN is a painful condition. Although there are multiple surgical approaches, we believe that percutaneous balloon compression is an excellent alternative treatment option that offers high effectiveness, low morbidity, and low hospital stay.

Electroencephalography spectral edge frequency and suppression rate-guided sedation in patients with COVID-19: A randomized controlled trial

Background

Sedation in coronavirus disease 2019 (COVID-19) patients has been identified as a major challenge. We aimed to investigate whether the use of a multiparameter electroencephalogram (EEG) protocol to guide sedation in COVID-19 patients would increase the 30-day mechanical ventilation-free days (VFD).

Methods

We conducted a double-blind randomized clinical trial. We included patients with severe pneumonia due to COVID-19 who required mechanical ventilation (MV) and deep sedation. We randomized to the control (n = 25) or multiparameter group (n = 25). Sedation in the intervention group was administered following the standard institutional protocols together with a flow chart designed to reduce the propofol administration dose if the EEG suppression rate was over 2% or the spectral edge frequency 95 (SEF95) was below 10 Hz. We performed an intention-to-treat analysis to evaluate our primary outcome (30-day VFD).

Results

There was no difference in VFD at day 30 (median: 11 [IQR 0–20] days in the control group vs. 0 [IQR 0–21] days in the BIS multiparameter group, p = 0.87). Among secondary outcomes, we documented a 17% reduction in the total adjusted propofol administered during the first 5 days of the protocol [median: 2.3 (IQR 1.9–2.8) mg/k/h in the control group vs. 1.9(IQR 1.5–2.2) mg/k/h in the MP group, p = 0.005]. This was accompanied by a higher average BIS value in the intervention group throughout the treatment period.

Conclusion

A sedation protocol guided by multivariate EEG-derived parameters did not increase the 30-day VFD. However, the intervention led to a reduction in total propofol administration.

Pricing in Nonconvex Markets: How to Price Electricity in the Presence of Demand Response

Climate change and the transition to renewable energy sources have had a significant impact on wholesale electricity markets. This has led to renewed interest in the design of electricity markets and pricing rules for spot markets. It is well known that theoretical ideals such as Walrasian equilibria cannot be obtained because of the nonconvex nature of the market-clearing problem. Instead, current pricing rules compute linear and anonymous price signals, yet at these prices, market participants often make a loss. Such losses are compensated by individual side payments that distort the price signal and have thus come under scrutiny by regulators. In this article, the authors examine this issue in greater detail. In markets with price-sensitive or flexible demand—which becomes increasingly important with growing levels of renewables—there can be no linear pricing rule that avoids make-whole payments under the welfare-maximizing allocation. Motivated by this observation, the authors introduce a pricing rule that minimizes make-whole payments and compare it against alternative pricing schemes. Numerical experiments indicate how the novel pricing rule can substantially reduce make-whole payments without significant impact on the overall market price. The findings provide input for the ongoing policy debate on make-whole payments in wholesale electricity markets.

POS1199 IS PSORIATIC ARTHRITIS A RISK FACTOR FOR SEVERE COVID -19 INFECTION? DATA FROM THE ARGENTINIAN REGISTRY SAR-COVID

Background

Comorbidities, particularly cardio-metabolic disorders, are highly prevalent in patients with psoriatic arthritis (PsA) and they were associated with an increased risk of atherosclerotic cardiovascular disease, which have been associated with higher morbidity and mortality. Whether PsA enhances the risk of SARS-CoV-2 infection or affects the disease outcome remains to be ascertained.

Objectives

To describe the sociodemographic, clinical and treatment characteristics of patients with PsA with confirmed SARS-CoV-2 infection from the SAR-COVID registry and to identify the variables associated with poor COVID-19 outcomes, comparing them with those with rheumatoid arthritis (RA).

Methods

Cross-sectional observational study including patients ≥18 years old, with diagnosis of PsA (CASPAR criteria) and RA (ACR / EULAR 2010 criteria), who had confirmed SARS-CoV-2 infection (RT-PCR or serology) from the SAR-COVID registry. Recruitment period was between August 13, 2020 and July 31, 2021. Sociodemographic variables, comorbidities, and treatments were analyzed. To assess the severity of the infection, the ordinal scale of the National Institute of Allergy and Infectious Diseases (NIAID)1 was used, and it was considered that a patient met the primary outcome, if they presented criteria of categories 5 or higher on the severity scale. For this analysis, Chi2 test, Fisher’s test, Student’s test or Wilcoxon test, and binomial logistic regression using NIAID>=5 as dependent variable were performed.

Results

A total of 129 PsA patients and 808 with RA were included. Clinical characteristics are shown in Table 1. Regarding PsA treatment, 12.4% of PsA were receiving IL-17 inhibitors, 5.4% IL12-23 inhibitors, one patient apremilast and one abatacept. The frequency of NIAID≥5 was comparable between groups (PsA 19.5% vs RA 20.1%; p=0.976). (Figure 1).

Table 1.

Characteristics of patients with PsA and RA who presented COVID-19 in the SAR-COVID registry.

Psoriatic arthritis (n=129)Rheumatoid arthritis (n=808)P valueTotal (n=937)Age (years), mean (SD)51.7 (12.7)53.1 (12.9)0.23952.9 (12.9)Female72 (55.8)684 (84.7)<0.001756 (80.7)Comorbidities65 (50.4)355 (43.9)0.203420 (44.8) Obesity (BMI ≥30)19 (15.2)102 (13.4)0.692121 (13.7) Morbid obesity (BMI ≥40)1 (0.8)10 (1.3)111 (1.25) Hypertension35 (28.5)205 (26.8)0.783240 (27.0) Diabetes16 (13.0)67 (8.8)0.18883 (9.39) Dyslipidemia24 (19.5)102 (13.5)0.106126 (14.4) Cardiovascular or cerebrovascular disease5 (11.4)32 (3.9)0.03337 (4.2)Two or more comorbidities55 (42.6)219 (27.1)<0.001274 (29.2)Current smoking4 (3.6)60 (8.4)0.7964 (7.7)High disease activity0 (0)29 (3.8)0.02729 (3.23)Glucocorticoids treatment5 (20.0)95 (60.1)<0.001100 (54.6)Conventional DMARDs47 (36.4)443 (54.8)<0.001490 (52.3)Biologic DMARDs60 (46.5)193 (23.9)<0.001253 (27.0)JAK inhibitors4 (3.10)72 (8.9)0.03876 (8.1)Full recovery of COVID-19105 (84.0)644 (81.7)0.127749 (82.0)COVID-19 complications16 (12.5)68 (8.7)0.22784 (9.2)Death due to COVID-191 (0.8)34 (4.3)0.07435 (3.8)

Notes=values n (%) unless otherwise indicated; BMI: Body Mass Index; DMARDs: disease-modifying antirheumatic drugs; JAK inhibitors: Janus kinase inhibitors.

PsA patients with NIAID≥5 in comparison with NIAID<5 were older (58.6±11.4 vs 50±12.5; p=0.002), had more frequently hypertension (52.2% vs 23%; p=0.011) and dyslipidemia (39.1% vs 15%; p=0.017). In the multivariate analysis, age (OR 1.06; 95% CI 1.02–1.11) was associated with a worse outcome of the COVID-19 (NIAID≥5) in patients with PsA, while those who received methotrexate (OR 0.34; 95% CI 0.11–0.92) and biological DMARDs (OR 0.28; 95% CI 0.09–0.78) had a better outcome.

Conclusion

Although PsA patients have a higher frequency of cardiovascular and metabolic comorbidities than those with RA, the COVID-19 severity was similar. Most of the patients had mild SARS-CoV-2 infection and a low death rate.

References

[1]Beigel JH, et al. Remdesivir for the Treatment of Covid-19 - Final Report. N Engl J Med. 2020 Nov 5;383(19):1813-1826.

Disclosure of Interests

None declared

POS1200 DIFFERENCES BETWEEN THE FIRST AND THE SECOND WAVE OF SARS-COV-2 INFECTION IN PATIENTS WITH IMMUNE-MEDIATED INFLAMMATORY DISEASES IN ARGENTINA: DATA FROM THE SAR-COVID REGISTRY

Background

In Argentina we have witnessed two COVID 19 waves between 2020 and 2021. The first wave occurred during the spring of 2020 and it was related to the wild type of the virus, the second occurred during the fall/winter of 2021 when the gamma variant showed a clear predominance. During the first wave, patient with rheumatic diseases showed a higher frequency of hospitalization and mortality (4% vs 0.26%) when compared to the general population1; at that time, however, vaccination was not yet available.

Objectives

To compare sociodemographic and disease characteristics, course and outcomes of SARS-CoV-2 infection in patients with immune-mediated/autoinflammatory diseases (IMADs) during the first and second waves in Argentina.

Methods

SAR-COVID is a national, multicenter, longitudinal and observational registry, in which patients ≥18 years of age, with a diagnosis of a rheumatic disease who had confirmed SARS-CoV-2 infection (RT-PCR or positive serology) were consecutively included since August 2020. For the purpose of this report, only patients with IMADs who had SARS-CoV-2 infection during the first wave (defined as cases occurred between March 2020 and March 2021) and the second wave (cases occurred between April and August 2021) were examined. Sociodemographic characteristics, disease diagnosis and activity, comorbidities, immunosuppressive treatment and COVID 19 clinical characteristics, complications and outcomes: hospitalization, intensive care unit (ICU) admission, use of mechanical ventilation and death were compared among groups. Descriptive statistical analysis was performed. Variables were compared with Chi squared test and Student T test or Mann Whitney test. Multivariable logistic regression models with forward and backward selection method, using hospitalization, ICU admission and death as dependent variables were carried out.

Results

A total of 1777 patients were included, 1342 from the first wave and 435 of the second one. Patients had a mean (SD) age of 50.7 (14.2) years and 81% were female. Both groups of patients were similar in terms of socio-demographic features, disease diagnosis, disease activity, the use of glucocorticoids ≥ 10 mg/day and the immunosuppressive drugs (Table 1 below). Patients infected during the first wave have higher frequency of comorbidities (49% vs 41%; p= 0.004). Hospitalizations due to COVID 19 (31% vs 20%; p <0.001) and ICU admissions (9% vs 5%; p= 0.009) were higher during the first wave. No differences in the use of mechanical ventilation (16% vs 16%; p= 0.97) nor in the mortality rate (5% vs 4%; p= 0.41) were observed. In the multivariable analysis, after adjusting for demographics, clinical features and immunosuppressive treatment, patients infected during the second wave were 40% less likely to be hospitalized (OR= 0.6, IC95% 0.4-0.8) and to be admitted to the ICU (OR= 0.6, IC95% 0.3-0.9).

Table 1.Variable (% or Mean – SD)First wave(n=1342)Second wave(n=435)p ValueFemale gender81800.7Age (years)51.0 (14.5)50.0 (13.3)0.2Disease diagnosis Rheumatoid arthritis46461 Ankylosing spondylitis10110.8 Systemic lupus erythematosus171850.9 Systemic Scleroderma551 Sjögren´s syndrome650.7 Inflammatory myopathies330.5 Vasculitis430.4Disease activity High430.5Use of immune modulatorsDMARDcs53560.2DMARDts460.1DMARDb82821Use of glucocorticoids ≥10 mg12120.9Comorbidities49410.004

Conclusion

The impact of COVID 19 in Argentina, in terms of mortality in patients with IMADs was still higher compared to the general population during the second wave. However, the frequency of hospitalizations and ICU admissions was lower. These findings could be explained by the introduction of the SARS COV 2 vaccination and, probably, by the cumulative knowledge and management improvement of this infection among physicians.

References

[1]Isnardi CA et al. Epidemiology and outcomes of patients with rheumatic diseases and SARS-COV-2 infection: data from the argentinean SAR-COVID Registry. Ann Rheum Dis, 2021, suppl 1, 887.

Disclosure of Interests

None declared

Relationship Between Endothelial and Angiogenesis Biomarkers Envisage Mortality in a Prospective Cohort of COVID-19 Patients Requiring Respiratory Support

Purpose

Endothelial damage and angiogenesis are fundamental elements of neovascularisation and fibrosis observed in patients with coronavirus disease 2019 (COVID-19). Here, we aimed to evaluate whether early endothelial and angiogenic biomarkers detection predicts mortality and major cardiovascular events in patients with COVID-19 requiring respiratory support.

Methods

Changes in serum syndecan-1, thrombomodulin, and angiogenic factor concentrations were analysed during the first 24 h and 10 days after COVID-19 hospitalisation in patients with high-flow nasal oxygen or mechanical ventilation. Also, we performed an exploratory evaluation of the endothelial migration process induced by COVID-19 in the patients' serum using an endothelial cell culture model.

Results

In 43 patients, mean syndecan-1 concentration was 40.96 ± 106.9 ng/mL with a 33.9% increase (49.96 ± 58.1 ng/mL) at day 10. Both increases were significant compared to healthy controls (Kruskal–Wallis p < 0.0001). We observed an increase in thrombomodulin, Angiopoietin-2, human vascular endothelial growth factor (VEGF), and human hepatocyte growth factor (HGF) concentrations during the first 24 h, with a decrease in human tissue inhibitor of metalloproteinases-2 (TIMP-2) that remained after 10 days. An increase in human Interleukin-8 (IL-8) on the 10th day accompanied by high HGF was also noted. The incidence of myocardial injury and pulmonary thromboembolism was 55.8 and 20%, respectively. The incidence of in-hospital deaths was 16.3%. Biomarkers showed differences in severity of COVID-19. Syndecan-1, human platelet-derived growth factor (PDGF), VEGF, and Ang-2 predicted mortality. A multiple logistic regression model with TIMP-2 and PDGF had positive and negative predictive powers of 80.9 and 70%, respectively, for mortality. None of the biomarkers predicted myocardial injury or pulmonary thromboembolism. A proteome profiler array found changes in concentration in a large number of biomarkers of angiogenesis and chemoattractants. Finally, the serum samples from COVID-19 patients increased cell migration compared to that from healthy individuals.

Conclusion

We observed that early endothelial and angiogenic biomarkers predicted mortality in patients with COVID-19. Chemoattractants from patients with COVID-19 increase the migration of endothelial cells. Trials are needed for confirmation, as this poses a therapeutic target for SARS-CoV-2.

POS1186 EFFECT OF SOCIO-ECONOMIC STATUS AND EDUCATIONAL LEVEL ON COVID-19 OUTCOMES IN PATIENTS WITH RHEUMATIC DISEASES FROM ARGENTINA: DATA FROM THE SAR-COVID REGISTRY

Background:

SARS-CoV-2 infection can present with a broad clinical spectrum, from asymptomatic to lethal. Different risk factors have been recognized. Socio-economic status and educational level may affect access to the healthcare system and therefore COVID-19 infection outcome.

Objectives:

The aim of this study was to assess the association between socio-demographic status and educational level and SARS-CoV-2 outcomes, such as hospitalization, ICU admission, need for mechanical ventilation and death, in Argentinean patients with rheumatic diseases from the SAR-COVID Registry.

Methods:

We performed a cross-sectional study of consecutive adult patients with rheumatic diseases and SARS-CoV-2 infection included in the multicentric Argentinean SAR-COVID Registry. The following variables were included: gender, ethnicity, age, health insurance, educational level (under or over 12 years of education), socio-economic level according to Graffar Scale in high, medium-high, medium, medium-low, low; underlying rheumatic disease, its duration and treatment at the time of infection.

SARS-CoV-2 infection outcomes were: hospitalization, admission to ICU, mechanical ventilation requirement and death.

Statistical analysis was performed using Chi2, Fisher, T-test, ANOVA.

Results:

Five hundred and twenty-five patients were included, 422 (80.4%) were female, with a mean age of 51.3 years (SD 15.2). Most of them were caucasians (48%) or mestizos (43%) and 96.8% lived in an urban environment. Almost half of the patients (47%) were categorized as middle-class, 24% middle-high or high class, 21% middle-low or low. 48.4% of the patients were employed. Regarding educational level, 54% had more than 12 years of education.

The most prevalent rheumatic disease was Rheumatoid Arthritis (40.4%), followed by Systemic Lupus Erythematosus (14.9%), Sjögren (5.5%) and Psoriatic Arthritis (5.5%). Treatments used at the time of SARS-CoV-2 infection were corticosteroids (19%), cs-DMARDs (49%), and b- and ts-DMARDs (16%).

Overall hospitalization frequency was 35%, median hospital stay was 10 days (IQR 10 days), 11.6% were admitted to the ICU, 10% required mechanical ventilation and the global mortality was 8%.

Notably, patients with less than 12 years of education required mechanical ventilation more frequently than the more educated ones (11.9% vs. 5.6%, p=0.026) and showed a higher mortality due to COVID-19 (9% vs. 2.8%, p=0.0004).

Patients categorized as upper social classes (middle-high and high) were admitted to the hospital on a more frequent basis (74.4% of cases), when compared with middle class (64.4%) and middle-low and low class (58%) (p=0.77). Median duration of hospitalization for the aforementioned groups was 12.5 (IQR 17.3), 10 (IQR 9) and 10.5 (IQR 9.3) days respectively (p=0.60).

Patients with health insurance were found to be hospitalized more frequently in comparison to those without insurance (42.4% vs. 33.7%, p=0.14), but showed similar admission rates to the ICU (11.8% vs. 12.8%; p=0.78), need for mechanical ventilation (10.7% vs. 8.7%; p=0.70) and mortality (7.1% vs. 6.5%; p=0.99).

Caucasian patients had fewer hospital admissions when compared against other ethnicities (mestizos mostly) (26.1% vs. 43.4%; p<0.0001), but showed no statistically significant difference in need for mechanical ventilation 10.3% vs. 9.9% (p=0.99) or mortality 8.7% vs. 5.1% (p=0.15).

Conclusion:

Patients with lower educational level needed twice the frequency of mechanical ventilation, and showed thrice the mortality than those with more than 12 years of education.

Albeit patients in upper social stratus and those with health insurance were admitted to the hospital in a more frequent manner, no statistically significant differences were found regarding the need for ICU, mechanical ventilation or mortality.

Caucasians were hospitalized less frequently than mestizos, but had no significant differences in the other measured outcomes.

Disclosure of Interests:

Laura Sorrentino Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Jonathan Rebak Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Federico Maldonado Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Vanessa Viviana Castro Coello Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Alejandro Brigante Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Adriana Hamaui Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Diana Dubinsky Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Roberto Baez Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Cecilia Pisoni Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Carla Gobbi Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Leandro Carlevaris Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Romina Tanten Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Adriana Karina Cogo Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Maria DeLaVega Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Rodolfo Perez Alamino Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Maria Alicia Lazaro Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Mariana Pera Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Susana Isabel Pineda Vidal Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Maria Elena Calvo Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Debora Guaglianone Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Carla G Alonso Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Mara Guinsburg Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Cinthya Retamozo Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Carolina Aeschlimann Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Rosana Quintana Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Karen Roberts Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Carolina Ayelen Isnardi Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data., Guillermo Pons Estel Grant/research support from: Unrestricted grants: Pfizer, Abbvie, Elea Phoenix. None of them have access to patient data.

Speech metrics, general disability, brain imaging and quality of life in multiple sclerosis

BACKGROUND AND PURPOSE

Objective measurement of speech has shown promising results to monitor disease state in multiple sclerosis. In this study, we characterize the relationship between disease severity and speech metrics through perceptual (listener based) and objective acoustic analysis. We further look at deviations of acoustic metrics in people with no perceivable dysarthria.

METHODS

Correlations and regression were calculated between speech measurements and disability scores, brain volume, lesion load and quality of life. Speech measurements were further compared between three subgroups of increasing overall neurological disability: mild (as rated by the Expanded Disability Status Scale ≤2.5), moderate (≥3 and ≤5.5) and severe (≥6).

RESULTS

Clinical speech impairment occurred majorly in people with severe disability. An experimental acoustic composite score differentiated mild from moderate (P < 0.001) and moderate from severe subgroups (P = 0.003), and correlated with overall neurological disability (r = 0.6, P < 0.001), quality of life (r = 0.5, P < 0.001), white matter volume (r = 0.3, P = 0.007) and lesion load (r = 0.3, P = 0.008). Acoustic metrics also correlated with disability scores in people with no perceivable dysarthria.

CONCLUSIONS

Acoustic analysis offers a valuable insight into the development of speech impairment in multiple sclerosis. These results highlight the potential of automated analysis of speech to assist in monitoring disease progression and treatment response.

Effect of sevoflurane and propofol on tourniquet-induced endothelial damage: a pilot randomized controlled trial for knee-ligament surgery

BACKGROUND

The glycocalyx layer is a key structure in the endothelium. Tourniquet-induced ischemic periods are used during orthopedic surgery, and the reactive oxygen species generated after ischemia-reperfusion may mediate the shedding of the glycocalyx. Here, we describe the effects of tourniquet-induced ischemia-reperfusion and compare the effects of sevoflurane and propofol on the release of endothelial biomarkers after ischemia-reperfusion in knee-ligament surgery.

METHODS

This pilot, single-center, blinded, randomized, controlled trial included 16 healthy patients. After spinal anesthesia, hypnosis was achieved with sevoflurane or propofol according to randomization. During the perioperative period, five venous blood samples were collected for quantification of syndecan-1, heparan sulfate, and thrombomodulin from blood serum by using ELISA assays kits. Sample size calculation was performed to detect a 25% change in the mean concentration of syndecan-1 with an alpha of 0.05 and power of 80%.

RESULTS

For our primary outcome, a two-way ANOVA with post-hoc Bonferroni correction analysis showed no differences in syndecan-1 concentrations between the sevoflurane and propofol groups at any time point. In the sevoflurane group, we noted an increase in syndecan-1 concentrations 90 min after tourniquet release in the sevoflurane group from 34.6 ± 24.4 ng/mL to 47.9 ± 29.8 ng/mL (Wilcoxon test, p < 0.01) that was not observed in patients randomized to the propofol group. The two-way ANOVA showed no intergroup differences in heparan sulfate and thrombomodulin levels.

CONCLUSIONS

Superficial endothelial damage without alterations in the cell layer integrity was observed after tourniquet knee-ligament surgery. There was no elevation in serum endothelial biomarkers in the propofol group patients. Sevoflurane did not show the protective effect observed in in vitro and in vivo studies.

TRIAL REGISTRATION

The trial was registered in www.clinicaltrials.gov (ref: NCT03772054, Registered 11 December 2018).

Catéter de drenaje de líquido cefalorraquídeo: usos, técnica y complicaciones para el anestesiólogo

La instalación de un catéter de drenaje espinal es un procedimiento indicado principalmente en la reparación de aneurismas aórticos y en el escenario de neurocirugía. No siempre es un procedimiento fácil de realizar donde surgen dudas sobre indicación, técnica y eventuales complicaciones. En el siguiente artículo revisamos cada uno de estos temas.

Association between pre-operative serum lactate concentrate with tumour cell proliferative index in primary brain tumour

BACKGROUND

Elevated preoperative lactate levels have been reported in patients admitted for resection of brain tumors. As histologic type and tumor grade have also been linked to lactate concentration, we hypothesized that preoperative lactate concentration in patients with brain tumors may be associated with tumor proliferation. We describe the relationship between preoperative plasma lactate levels, and the cell proliferation marker Ki-67 in brain tumor surgery.

METHODS

In this cross-sectional study, records of patients who underwent craniotomy between June 2017 and February 2018 at our Hospital were reviewed to select glioma and meningioma cases in which lactate concentrations in plasma and degree of cell proliferation were registered. Bivariable and linear regression analyses were used to assess the association between lactate concentrations and the Ki-67 index.

RESULTS

Lactate concentrations in plasma and Ki-67 index were available in 55 patients. Meningioma cases had a mean concentration of 1.2 (0.1) mmol/L compared to diffuse astrocytic and oligodendroglial tumours cases with 1.7 (0.1) mmol/L (p<.01). Both variables had a low positive correlation in meningiomas (Spearman's r, 0.29; 95% CI, -0.10-0.61; p=.13) and a high correlation in gliomas (Spearman's r, 0.64; 95% CI, 0.33-0.82; p<.01). The pooled analysis showed a high correlation index (Spearman's r, 0.61; 95% CI, 0.40-0.76; p<.01). A linear regression model showed that the Ki-67 index explained 43% of the variation in lactate (p<.01).

CONCLUSIONS

Brain tumors with higher rates of cell proliferation have higher plasma lactate levels. In this scenario, lactate concentrations may not only reflect systemic perfusion.

Abnormal pulmonary function tests predict the development of radiation-induced pneumonitis in advanced non-small cell lung Cancer

BACKGROUND

Radiation pneumonitis (RP) is a frequent complication of concurrent chemoradiotherapy (CCRT) and is associated with severe symptoms that decrease quality of life and might result in pulmonary fibrosis or death. The aim of this study is to identify whether pulmonary function test (PFT) abnormalities may predict RP in non-small cell lung cancer (NSCLC) patients.

METHODS

A prospective multi-institutional study was conducted with locally advanced and oligometastatic NSCLC patients. All participants were evaluated at baseline, end of CCRT, week 6, 12, 24, and 48 post-CCRT. They completed forced spirometry with a bronchodilator, body plethysmography, impulse oscillometry, carbon monoxide diffusing capacity (DLCO), molar mass of CO2, six-minute walk test and exhaled fraction of nitric oxide (FeNO). Radiation pneumonitis was assessed with RTOG and CTCAE. The protocol was registered in www.clinicaltrials.gov (NCT01580579), registered April 19, 2012.

RESULTS

Fifty-two patients were enrolled; 37 completed one-year follow-up. RP ≥ Grade 2 was present in 11/37 (29%) for RTOG and 15/37 (40%) for CTCAE. Factors associated with RP were age over 60 years and hypofractionated dose. PFT abnormalities at baseline that correlated with the development of RP included lower forced expiratory volume in one second after bronchodilator (p = 0.02), DLCO (p = 0.02) and FeNO (p = 0.04). All PFT results decreased after CCRT and did not return to basal values at follow-up.

CONCLUSIONS

FEV1, DLCO and FeNO prior to CCRT predict the development of RP in NSCLC. This study suggests that all patients under CCRT should be assessed by PFT to identify high-risk patients for close follow-up and early treatment.

Aged blood factors decrease cellular responses associated with delayed gingival wound repair

Aging is a gradual biological process characterized by a decrease in cell and organism functions. Gingival wound healing is one of the impaired processes found in old rats. Here, we studied the in vivo wound healing process using a gingival repair rat model and an in vitro model using human gingival fibroblast for cellular responses associated to wound healing. To do that, we evaluated cell proliferation of both epithelial and connective tissue cells in gingival wounds and found decreased of Ki67 nuclear staining in old rats when compared to their young counterparts. We next evaluated cellular responses of primary gingival fibroblast obtained from young subjects in the presence human blood serum of individuals of different ages. Eighteen to sixty five years old masculine donors were classified into 3 groups: “young” from 18 to 22 years old, “middle-aged” from 30 to 48 years old and “aged” over 50 years old. Cell proliferation, measured through immunofluorescence for Ki67 and flow cytometry for DNA content, was decreased when middle-aged and aged serum was added to gingival fibroblast compared to young serum. Myofibroblastic differentiation, measured through alpha-smooth muscle actin (α-SMA), was stimulated with young but not middle-aged or aged serum both the protein levels and incorporation of α-SMA into actin stress fibers. High levels of PDGF, VEGF, IL-6R were detected in blood serum from young subjects when compared to middle-aged and aged donors. In addition, the pro-inflammatory cytokines MCP-1 and TNF were increased in the serum of aged donors. In old rat wound there is an increased of staining for TNF compared to young wound. Moreover, healthy gingiva (non injury) shows less staining compared to a wound site, suggesting a role in wound healing. Moreover, serum from middle-aged and aged donors was able to stimulate cellular senescence in young cells as determined by the expression of senescence associated beta-galactosidase and histone H2A.X phosphorylated at Ser139. Moreover, we detected an increased frequency of γ-H2A.X-positive cells in aged rat gingival tissues. The present study suggests that serum factors present in middle-aged and aged individuals may be responsible, at least in part, for the altered responses observed during wound healing in aging.

Malignant transformation of a tracheal chondroma: The second reported case and review of the literature

Tracheal tumors are rare, representing only 0.2% of the respiratory tract malignancies. Chondrosarcoma arising in the trachea was first described in 1959 by Jackson et al. and since then only 20 cases have been described. We report the second documented case of malignant transformation from an endotracheal chondroma, in a 75-year-old woman, and review the literature.

The diagnosis of pleural effusions

Pleural effusions arise from a variety of systemic, inflammatory, infectious and malignant conditions. Their precise etiological diagnosis depends on a combination of medical history, physical examination, imaging tests and pertinent pleural fluid analyses; including specific biomarkers (e.g., natriuretic peptides for heart failure, adenosine deaminase for tuberculosis, or mesothelin for mesothelioma). Invasive procedures, such as pleuroscopic biopsies, may be required for persistently symptomatic effusions which remain undiagnosed after the analysis of one or more pleural fluid samples. However, whenever parietal pleural nodularity or thickening exist, image-guided biopsies should first be attempted. This review addresses the current diagnostic approach to pleural effusions secondary to heart failure, pneumonia, cancer, tuberculosis and other less frequent conditions.

A Mayan founder mutation is a common cause of deafness in Guatemala

Over 5% of the world's population has varying degrees of hearing loss. Mutations in GJB2 are the most common cause of autosomal recessive non-syndromic hearing loss (ARNHL) in many populations. The frequency and type of mutations are influenced by ethnicity. Guatemala is a multi-ethnic country with four major populations: Maya, Ladino, Xinca, and Garifuna. To determine the mutation profile of GJB2 in a ARNHL population from Guatemala, we sequenced both exons of GJB2 in 133 unrelated families. A total of six pathogenic variants were detected. The most frequent pathogenic variant is c.131G>A (p.Trp44*) detected in 21 of 266 alleles. We show that c.131G>A is associated with a conserved haplotype in Guatemala suggesting a single founder. The majority of Mayan population lives in the west region of the country from where all c.131G>A carriers originated. Further analysis of genome-wide variation of individuals carrying the c.131G>A mutation compared with those of Native American, European, and African populations shows a close match with the Mayan population.

Early hyperglycemia: a risk factor for posttransplant diabetes mellitus among renal transplant recipients

To ascertain the frequency, epidemiology, and risk factors of posttransplant diabetes mellitus (PTDM), a retrospective analysis of all first renal transplantations, without personal history of diabetes (DM) and with a follow up >or=6 months, was performed. All patients received methylprednisolone (0.5-1 g IV) immediately prior to surgery, followed by immunosuppression including steroids, cyclosporine, and azathioprine most frequently. Early hyperglycemia was defined as values >126 mg/dL during the first week after transplantation and DM by 2 blood glucose levels of >126 mg/dL after the first month of follow-up. Included were 163 patients, namely, 57.6% males and 66% recipients of a deceased donor and 12% with a first-degree family history of DM. Mean age at transplantation was 39 years (range, 17-70 years) with a mean follow-up of 64 months. Among the 163 total subjects, some developed PTDM with frequencies of 7.5%, 13%, and 23% at 1, 5, and 10 years, respectively. Among patients with a first-degree family history of DM, 37% developed PTDM compared with 14% of those without it (odds ratio [OR] = 3.6; P < .05). Early hyperglycemia was observed in 55/92 patients, 15 of whom developed PTDM. Among patients with PTDM, the frequency of early hyperglycemia was 87% compared with 54% among those who did not develop this complication (OR = 5.4; P < .05). We confirmed a high frequency of PTDM, identifying risk factors such as a first-degree family history of DM and the development of early hyperglycemia, which should be taken into account to increase our diagnostic sensitivity and improve therapeutic individualization among renal transplant patients.

Usual interstitial pneumonia in rheumatoid arthritis-associated interstitial lung disease

Interstitial lung disease is a common manifestation of rheumatoid arthritis; however, little is known about factors that influence its prognosis. The aim of the present study was to determine whether or not the usual interstitial pneumonia pattern found on high-resolution computed tomography (HRCT) is of prognostic significance in rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Patients with RA-ILD were identified retrospectively (n = 82). The relationship of a definite usual interstitial pneumonia pattern on HRCT to survival was determined and compared to that in a cohort of patients with radiologically diagnosed idiopathic pulmonary fibrosis (n = 51). A definite usual interstitial pneumonia pattern was seen in 20 (24%) out of 82 patients with RA-ILD. These patients showed worse survival than those without this pattern (median survival 3.2 versus 6.6 yrs), and a similar survival to those with idiopathic pulmonary fibrosis. On multivariate analysis, a definite usual interstitial pneumonia pattern on HRCT was associated with worse survival (hazard ratio of 2.3). Analysis of specific HRCT features demonstrated that traction bronchiectasis and honeycomb fibrosis were associated with worse survival (hazard ratio of 2.6 and 2.1, respectively). Female sex (hazard ratio of 0.30) and a higher baseline diffusing capacity of the lung for carbon monoxide (hazard ratio of 0.96) were associated with better survival. A definite usual interstitial pneumonia pattern on HRCT has important prognostic implications in RA-ILD.

In vitro resistance study of rupintrivir, a novel inhibitor of human rhinovirus 3C protease

Rupintrivir (formerly AG7088) is an irreversible inhibitor of the human rhinovirus (HRV) 3C protease that has been demonstrated to have in vitro activity against all HRVs tested, consistent with its interaction with a strictly conserved subset of amino acids in the 3C protease. The potential for resistance was studied following in vitro serial passage of HRV serotypes 14, 2, 39, and Hanks in the presence of increasing rupintrivir concentrations. HRV variants with reduced susceptibilities to rupintrivir (sevenfold for HRV 14) or with no significant reductions in susceptibility but genotypic changes (HRV 2, 39, and Hanks) were initially isolated following 14 to 40 cumulative days in culture (three to six passages). Sequence analysis of the 3C protease identified one to three substitutions in diverse patterns but with common features (T129T/A, T131T/A, and T143P/S in HRV 14; N165T in HRV 2; N130N/K and L136L/F in HRV 39; T130A in HRV Hanks). Notably, three of the four HRV variants contained a substitution at residue 130 (residue 129 in HRV 14). Continued selection in the presence of escalating concentrations of rupintrivir (40 to 72 days) resulted in the accumulation of additional mutations (A121A/V and Y139Y/H in HRV 14, E3E/G and A103A/V in HRV 2, S105T in HRV 39), with only minimal further reductions in susceptibility (up to fivefold). The ability of specific substitutions to confer resistance was examined by susceptibility testing of HRV 14 variants constructed to contain 3C protease mutations. In summary, the slow accumulation of multiple amino acid substitutions with only minimal to moderate reductions in susceptibility highlight the advantages of 3C protease as an antiviral target.

Chemotherapy alternating gemcitabine and cisplatin concomitant with radiotherapy in locally advanced (LA) squamous cell carcinoma of the head and neck (SCCHN)

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Background: In the Pignon’s meta-analysis, the OS benefit was 8% with chemoradiation in LA SCCHN. Unfortunately it is still unclear what scheme is the best, cisplatin (CDDP) being the most widely used drug. Other drugs such as gemcitabine (GMZ) has promising results, although toxicity has been severe but tolerable. We have published an initial study using GMZ and radiotherapy (ann oncol. 2004;15:301). In the present study we wished to determine if a scheme in which GMZ is alternated with CDDP and concomitant radiotherapy reduced toxicity yet maintains our previously described therapeutic effectiveness. This is a preliminary report with a short follow-up period. Methods: Inclusion criteria: patients with SCCHN (EC: III, IVa and IVb ) or with recurring disease, and no sytemic metastases or patients rejection of surgery between 03/2003 and 09/2004. Chemotherapy scheme consisted of GMZ at 100 mg/m2 once a w, ws 1, 3, 5, 7 and CDDP at 50 mg/m2 once a w, ws 2, 4, y 6. Radiotherapy consisted of 2 Gy/day, for a total of 70 Gy during the 7 ws. Toxicity evaluation focused on mucositis, xerostomia, dysphagia y leukopenia. Results: 28 patients were treated. 7 (25%)/ stage III, 11 (39.3%) IVa, 10 (35.7%) IVb. The tumor sites distribution was as follows: 9 patients with oropharynx and larynx disease (32.1%), 6 patients with oral cavity disease (21.4%), 3 patients with paranasal sinus disease (10.7%), and 1 hypopharinx (3.5%). A CCR was observed in 21 patients (75%), a partial response was observed in 5 patients (17%). Organ preservation was achieved in 68% of the patients. Toxicity: mucositis Grade 3–4 was in 42% of patients, leucopenia grade III in 29%, dysphagia in 19% and xerostomia in 10%. 40%of the patients stopped treatment for one or two weeks due to toxicity without affecting the doses of both treatments. Conclusions: The scheme with alternating GMZ and CDDP concomitant with radiotherapy is safe and effective. We observed a lower incidence in mucositis and few systemic toxic effects. Our findings support further studies in which alternating chemotherapeutic schemes are utilized given that tumor response is increased without an increment in toxicity.

No significant financial relationships to disclose.

Phase II clinical trial preliminary report: Cetuximab, gemcitabine and simultaneous radiotherapy for locally advanced head and neck cancer: Preliminary report

15502

Background: Previous studies with cetuximab in SCCHN demonstrate to be clinically beneficial. In the present study we wished to evaluate the efficacy and safety of a chemotherapeutic scheme using gemcitabine, radiotherapy and cetuximab for SCCHN. Preliminary report of 20 of 40 enrolled patients into a phase II clinical trial. Methods: inclusion criteria; histological confirmation of epidermoid carcinoma, ages 18 to 70, K > 70%, normal renal, hepatic and haematologic functions, without previous treatment, surgically inoperable disease, or patients with operable disease that did not consent to surgery. All patients signed an informed consent form. Radiotherapy: 200 cGy/d/5/w until 70Gy were completed. Cetuximab: an initial dose of 400 mg/m2 one week prior to initiation of radiotherapy, followed by 250 mg/m2 weekly until completion of radiotherapy. Gemcitabine: 50 mg /m2 weeks 1–2, 4–5 and 7. Results: 20 patients were enrolled (16m/4f) from november of 2004 to november of 2005, (5 oral cavity, 5 oropharynx, 8 larynx, 1 hypopharynx and 1 paranasal sinus). Mean age 56 yrs (33–75). Tumor staging: 7/III, 8/IVa and 5/IVb. One female was excluded, 19 completed the study and were evaluated. GR 17/19 (89.5%), CR 13/17 (76.5%) and PR 4/17 (23.5%). 2/19 NR (10.5%). CR of the 1ary tumor 15/19 patients (78.9%); CR 6/11 patients with lymphatic disease at diagnosis (54.5%), PR 3/19 (27.3%). Toxicity: mucositis g/III-IV 8/19 patients; rash g/III 4 patients. 2/19 did not complete treatment with chemotherapy due to mucositis but did with radiotherapy. No relationship was found between clinical response and the severity of the rash. One patient developed leukopenia g/III. 4 patients developed disphagia g/II, one has not resolved after 8 month follow up. Xerostomia g/II was 7/19 patients. Dermatological toxicity resolved by the end of the treatment. Mean follow up: 6 months, 1 patient which did not respond died and 1 patient with a PR recurred. Conclusions: The scheme is safe and effective with tolerable toxicity. In our previously reported experience, the addition of cetuximab to gemcitabine and radiotherapy does not increment local toxicity, statistical validation of these findings require the completion of the 40 patient study.

No significant financial relationships to disclose.

[Helicobacter pylori detected in atheroma plaque]

INTRODUCTION

In general, infection and chronic inflammation have been implied as etiologic agents for atheroesclerosis and in particular coronary illness (CI). Several studies have correlated the infection of Helicobacter pylori with CI, especially with virulent strains (lineage Cag A).

OBJECTIVE

Demonstrate the immunohistochemical presence of H. Pylori in atheroscletotic plaques obtained from endarterectomy of different vascular regions.

MATERIAL AND METHODS

34 atherosclerotic plaques of different vascular areas were studied, (25 men and 9 women). The tissues were fixed with 10% neutral buffered-formalin and decalcifying in formic acid 5% was used when necessary. The tissue sections were included in paraffin, cut and colored with H&E and subjected to Immunohistochemistry (IHC) of H. Pylori. Briefly, tissues were deparaffinized and thermally treated with a citrate-based solution of antigenic retrieval (ImmunoDNA Retriever with Citrate, BIO SB, Santa Barbara, CA) using a water bath at 95 degrees C for 1 hour. The IHC was conducted using a high sensitivity Biotin-Streptavidin-HRP-DAB IHC system (ImmunoDetector HRP/DAB, BIO SB). The microscopic observation evaluated the presence of mononuclear inflammatory cells and the identification of the bacteria in the wall or the vascular lumen.

RESULTS

Of the 34 cases studied 14 were positive, where one could identify the bacillus in their different forms (41,17%) associated with chronic inflammation.

Conservation of amino acids in human rhinovirus 3C protease correlates with broad-spectrum antiviral activity of rupintrivir, a novel human rhinovirus 3C protease inhibitor

The picornavirus 3C protease is required for the majority of proteolytic cleavages that occur during the viral life cycle. Comparisons of published amino acid sequences from 6 human rhinoviruses (HRV) and 20 human enteroviruses (HEV) show considerable variability in the 3C protease-coding region but strict conservation of the catalytic triad residues. Rupintrivir (formerly AG7088) is an irreversible inhibitor of HRV 3C protease with potent in vitro activity against all HRV serotypes (48 of 48), HEV strains (4 of 4), and untyped HRV field isolates (46 of 46) tested. To better understand the relationship between in vitro antiviral activity and 3C protease-rupintrivir binding interactions, we performed nucleotide sequence analyses on an additional 21 HRV serotypes and 11 HRV clinical isolates. Antiviral activity was also determined for 23 HRV clinical isolates and four additional HEV strains. Sequence comparison of 3C proteases (n = 58) show that 13 and 11 of the 14 amino acids that are involved in side chain interactions with rupintrivir are strictly conserved among HRV and HEV, respectively. These sequence analyses are consistent with the comparable in vitro antiviral potencies of rupintrivir against all HRV serotypes, HRV isolates, and HEV strains tested (50% effective concentration range, 3 to 183 nM; n = 125). In summary, the conservation of critical amino acid residues in 3C protease and the observation of potent, broad-spectrum antipicornavirus activity of rupintrivir highlight the advantages of 3C protease as an antiviral target.

In vitro antiviral activity of AG7088, a potent inhibitor of human rhinovirus 3C protease

AG7088 is a potent, irreversible inhibitor of human rhinovirus (HRV) 3C protease (inactivation rate constant (k(obs)/[I]) = 1,470,000 +/- 440,000 M(-1) s(-1) for HRV 14) that was discovered by protein structure-based drug design methodologies. In H1-HeLa and MRC-5 cell protection assays, AG7088 inhibited the replication of all HRV serotypes (48 of 48) tested with a mean 50% effective concentration (EC(50)) of 0.023 microM (range, 0.003 to 0.081 microM) and a mean EC(90) of 0.082 microM (range, 0.018 to 0.261 microM) as well as that of related picornaviruses including coxsackieviruses A21 and B3, enterovirus 70, and echovirus 11. No significant reductions in the antiviral activity of AG7088 were observed when assays were performed in the presence of alpha(1)-acid glycoprotein or mucin, proteins present in nasal secretions. The 50% cytotoxic concentration of AG7088 was >1,000 microM, yielding a therapeutic index of >12,346 to >333,333. In a single-cycle, time-of-addition assay, AG7088 demonstrated antiviral activity when added up to 6 h after infection. In contrast, a compound targeting viral attachment and/or uncoating was effective only when added at the initiation of virus infection. Direct inhibition of 3C proteolytic activity in infected cells treated with AG7088 was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of radiolabeled proteins, which showed a dose-dependent accumulation of viral precursor polyproteins and reduction of processed protein products. The broad spectrum of antiviral activity of AG7088, combined with its efficacy even when added late in the virus life cycle, highlights the advantages of 3C protease as a target and suggests that AG7088 will be a promising clinical candidate.