Hydrogen-Deuterium Exchange Epitope Mapping of Glycosylated Epitopes Enabled by Online Immobilized Glycosidase.

Hydrogen-deuterium exchange coupled with mass spectrometry (HDX-MS) is widely used for monoclonal antibody (mAb) epitope mapping, which aids in the development of therapeutic mAbs and vaccines, as well as enables the understanding of viral immune evasion. Numerous mAbs are known to recognize N-glycosylated epitopes and to bind in close proximity to an N-glycan site; however, glycosylated protein sites are typically obscured from HDX detection as a result of the inherent heterogeneity of glycans. To overcome this limitation, we covalently immobilized the glycosidase PNGase Dj on a solid resin and incorporated it into an online HDX-MS workflow for post-HDX deglycosylation. The resin-immobilized PNGase Dj exhibited robust tolerance to various buffer conditions and was employed in a column format that can be readily adapted into a typical HDX-MS platform. Using this system, we were able to obtain full sequence coverage of the SARS-CoV-2 receptor-binding domain (RBD) and map the glycosylated epitope of the glycan-binding mAb S309 to the RBD.

An indirect comparison of the efficacy and safety of desvenlafaxine and venlafaxine using placebo as the common comparator.

BACKGROUND: This meta-analysis compared the efficacy and safety of desvenlafaxine and venlafaxine at the Australian approved doses. METHODS: A systematic literature search was conducted to identify all placebo-controlled studies of desvenlafaxine and venlafaxine in the treatment of major depression. The pivotal outcome measure used to assess comparative efficacy was the mean change in Hamilton Rating Scale for Depression-17 score from baseline. Tolerability and safety were compared by an evaluation of reported adverse events. Standard and Bayesian methods were used to conduct the indirect comparisons. Findings Using a mixed model repeated measures analysis, the pooled weighted mean difference for the mean change in Hamilton Rating Scale for Depression-17 score from baseline was -2.81 (-3.72, -1.91; p < 0.001) for desvenlafaxine and -2.61 (-3.17, -2.05; p < 0.001) for venlafaxine. An indirect Bayesian analysis adjusted for baseline Hamilton Rating Scale for Depression-17 score showed no significant difference between the two treatments (weighted mean difference -0.27; -1.17, 0.65). A standard indirect comparison of any adverse events showed no significant difference between desvenlafaxine and venlafaxine (relative risk 1.01; 0.96, 1.06; p = 0.70 and risk difference -0.01; -0.05, 0.03; p = 0.59). Standard indirect comparisons of both nausea and drop-outs identified potential differences between treatments, with the risk difference analyses suggesting a trend in favor of desvenlafaxine (nausea: relative risk 0.97; 0.77, 1.22; p = 0.80/RD -0.07; -0.12, -0.01; p = 0.02; and drop-outs due to adverse events: RR 0.86; 0.58, 1.29; p = 0.48/RD -0.04; -0.08, 0.00; p = 0.06). CONCLUSIONS: Based on the results of this meta-analysis, desvenlafaxine was shown to be non-inferior to venlafaxine in terms of efficacy, and has an advantage in terms of less nausea.

Treatment-completion rates with olanzapine long-acting injection versus risperidone long-acting injection in a 12-month, open-label treatment of schizophrenia: indirect, exploratory comparisons.

BACKGROUND: Little is known about the comparative effectiveness of atypical antipsychotics in long-acting injection formulation. Due to the absence of head-to-head studies comparing olanzapine long-acting injection and risperidone long-acting injection, this study was intended to make exploratory, indirect, cross-study comparisons between the long-acting formulations of these two atypical antipsychotics in their effectiveness in treating patients with schizophrenia. METHODS: Indirect, cross-study comparisons between olanzapine long-acting injection and risperidone long-acting injection used 12-month treatment-completion rates, because discontinuation of an antipsychotic for any cause is a recognized proxy measure of the medication's effectiveness in treating schizophrenia. Following a systematic review of the literature, two indirect comparisons were conducted using open-label, single-cohort studies in which subjects were stabilized on an antipsychotic medication before depot initiation. The first analysis compared olanzapine long-acting injection (one study) with pooled data from nine identified risperidone long-acting injection studies. The second analysis was a "sensitivity analysis," using only the most similar studies, one for olanzapine long-acting injection and one for risperidone long-acting injection, which shared near-identical study designs and involved study cohorts with near-identical patient characteristics. Pearson Chi-square tests assessed group differences on treatment-completion rates. RESULTS: Comparison of olanzapine long-acting injection data (931 patients) with the pooled data from the nine risperidone long-acting injection studies (3950 patients) provided almost identical 12-month treatment-completion rates (72.7% versus 72.4%; P = 0.87). When the two most similar studies were compared, the 12-month completion rate for olanzapine long-acting injection was significantly higher than for risperidone long-acting injection (81.3% versus 47.0%; P < 0.001). However, any conclusions drawn from this comparison may be limited by differences in the studies' geographic catchment areas. CONCLUSION: Using treatment-completion rates as a proxy measure of medication effectiveness, olanzapine long-acting injection did not differ significantly from risperidone long-acting injection when including all eligible studies. However, the findings of this exploratory analysis should be interpreted with caution, considering the methodological limitations of these indirect, cross-study comparisons.

The epidemiology and cost of surgical site infections in Korea: a systematic review.

PURPOSE: To conduct a systematic literature review of the epidemiological and economic burden of surgical site infection (SSI) in Korea. METHODS: A search of the EMBASE, Medline and KoreaMed databases for English and Korean language publications was conducted. Searches for epidemiological and economic studies were conducted separately and limited to 1995 to 2010 to ensure the pertinence of the data. RESULTS: Twenty-six studies were included. The overall incidence of SSI in Korea was 2.0 to 9.7%. The National Nosocomial Infections Surveillance risk index was positively correlated with the risk of developing an SSI. Specific risk factors for SSI, identified through multivariate analyses included; diabetes, antibiotic prophylaxis and wound classification. SSIs were associated with increased hospitalisation cost, with each episode of SSI estimated to cost about an additional ₩2,000,000. A substantial portion of the increased cost was attributed to hospital room costs and the need for additional medication. Studies also found that post-operative stays for patients with SSIs were 5 to 20 days longer, while two studies reported that following cardiac surgery, patients with SSIs spent an additional 5 to 11 days in the intensive care unit, compared to patients without SSIs. CONCLUSION: Data from the included studies demonstrate that SSI represents a significant clinical and economic burden in Korea. Consequently, the identification of high-risk patient populations and the development of strategies aimed at reducing SSI may lead to cost-savings for the healthcare system.

Impact of membrane fusion and proteolysis on SpoIIQ dynamics and interaction with SpoIIIAH.

The onset of engulfment-dependent gene expression during Bacillus subtilis sporulation requires the forespore membrane protein SpoIIQ, which recruits mother cell proteins involved in late gene expression to the outer forespore membrane. Engulfment activates the late forespore transcription factor sigmaG, which produces high levels of the secreted SpoIVB protease that is required for activation of the late mother cell transcription factor sigmaK. Engulfment also triggers the proteolytic cleavage of SpoIIQ, an event that depends on the SpoIVB protease but not on sigmaG activity. To determine if SpoIVB directly cleaves SpoIIQ and to determine if this event participates in the onset of late gene expression, we purified SpoIVB, SpoIIQ, and SpoIVFA (another SpoIVB substrate). SpoIVB directly cleaved SpoIIQ at the same site in vitro and in vivo and cleaved SpoIVFA in at least three different locations. SpoIIQ cleavage depends on membrane fusion, but not on sigmaG activity, suggesting that the ability of SpoIVB to cleave substrates is regulated by membrane fusion. We isolated SpoIVB-resistant SpoIIQ proteins by random mutagenesis of codons at the cleavage site and demonstrated that SpoIIQ processing is dispensable for spore formation and for activation of late forespore and mother cell gene expression. Fluorescence recovery after photobleaching analysis demonstrated that membrane fusion releases SpoIIQ from an immobile complex, an event that could allow SpoIVB to cleave SpoIIQ. We propose that this membrane fusion-dependent reorganization in the complex, rather than SpoIIQ proteolysis itself, is necessary for the onset of late transcription.