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HIV-1 (human immunodeficiency virus-1) has been causing severe pandemics by attacking the immune system of its host. Left untreated, it can lead to AIDS (acquired immunodeficiency syndrome), where death is inevitable due to opportunistic diseases. Therefore, discovering new antiviral drugs against HIV-1 is crucial. This study aimed to explore a novel machine learning approach to classify compounds that inhibit HIV-1 integrase and screen the dataset of repurposing compounds. The present study had two main stages: selecting the best type of fingerprint or molecular descriptor using the Wilcoxon signed-rank test and building a computational model based on machine learning. In the first stage, we calculated 16 different types of fingerprint or molecular descriptors from the dataset and used each of them as input features for 10 machine-learning models, which were evaluated through cross-validation. Then, a meta-analysis was performed with the Wilcoxon signed-rank test to select the optimal fingerprint or molecular descriptor types. In the second stage, we constructed a model based on the optimal fingerprint or molecular descriptor type. This data followed the machine learning procedure, including data preprocessing, outlier handling, normalization, feature selection, model selection, external validation, and model optimization. In the end, an XGBoost model and RDK7 fingerprint were identified as the most suitable. The model achieved promising results, with an average precision of 0.928 ± 0.027 and an F1-score of 0.848 ± 0.041 in cross-validation. The model achieved an average precision of 0.921 and an F1-score of 0.889 in external validation. Molecular docking was performed and validated by redocking for docking power and retrospective control for screening power, with the AUC metrics being 0.876 and the threshold being identified at -9.71 kcal mol -1 . Finally, 44 compounds from DrugBank repurposing data were selected from the QSAR model, then three candidates were identified as potential compounds from molecular docking, and PSI-697 was detected as the most promising molecule, with in vitro experiment being not performed (docking score: -17.14 kcal mol -1 , HIV integrase inhibitory probability: 69.81%)., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

In this study, we establish an efficient enzymatic approach for producing novel inotodiyl-oleates (IOs) from pure inotodiol and oleic acid to improve the properties of inotodiol. For the esterification between inotodiol and oleic acid, CALA and n-hexane were the optimal biocatalyst and solvents for forming IOs with 80.17% conversion yield. These IOs comprised two distinct monoesters, the C3 or C22 ester forms of inotodiol. Intriguingly, no diesters were detected. The IOs had a melting point of 53.48 °C, much lower than that of inotodiol (192.06 °C). The in vitro digestion rate of IOs (25-28%) was significantly (p < 0.05) lower than that of cholesteryl-oleate (60%). Additionally, IOs exhibited much lower in vivo absorption than inotodiol when orally administered using different formulations (p < 0.05). The results indicated that IOs were resistant to enzymatic digestion in the small intestine, which could be advantageous in targeting the large intestine for disease treatments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Flow cytometry (FC) incorporating the T-cell receptor β constant chain-1 (TRBC1) has been recently proposed as a new standard in T-cell clonality assessment. While early studies demonstrated high sensitivity in samples with conspicuous tumour burden, performance in real-world samples, including those with low tumour burden and correlation with molecular methods has been limited. We evaluated TRBC1-FC performance and correlated the results with high-throughput TRB sequencing and a targeted next-generation sequencing gene panel. Our cohort consisted of 90 evaluable samples from 57 patients. TRBC1-FC confirmed T-cell clonality in 37 out of 38 samples (97%) that were involved in a mature T-cell neoplasm (MTCN). T-cell clonality was also identified in nine samples from patients lacking a current or prior diagnosis of MTCN, consistent with the emerging entity T-cell clonality of uncertain significance. TRBC-FC was polyclonal in all samples and negative for disease involvement by standard pathology assessment. However, correlation with TRB sequencing in 17 of these samples identified two cases that harboured the known clonal sequence from index testing, indicating the presence of measurable residual disease not otherwise detected. Our study provides real-world correlative validation of TRBC1-FC, highlighting the strengths and limitations pertinent to its increasing implementation by general diagnostic laboratories., (© 2023 British Society for Haematology and John Wiley & Sons Ltd.)

Acid-sulfate soils and overuse of chemical fertilizers have been obstacles to sustainable agriculture. The variation of fertilization due to poor soil fertility has remarkably affected the yield gap and the quality of the environment, so an optimal fertilizing rate should be formulated. Therefore, this study aimed at (i) detecting obstacles in soil characteristics reducing pineapple yield between farms and (ii) assessing the effects of NPKCaMg fertilizers on soil fertility, uptakes, and pineapple yield. The on-farm experiment was carried out according to site-specific nutrient management (SSNM) arranging in acid-sulfate soil for pineapple, including (i) no fertilizers used; (ii) NPKCaMg: fully fertilizing with nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg); (ii) PKCaMg: fertilizing without N; (iii) NKCaMg: fertilizing without P; (iv) NPCaMg: fertilizing without K; (v) NPKMg: fertilizing without Ca; (vi) NPKCa: fertilizing without Mg; and (vii) FFP: farmers' fertilizing practice. The result of the principal component analysis revealed that the soil had low availability of N, P, and K nutrients. Available P concentration was negatively correlated with concentrations of Al 3+ , Fe 2+ , and total Mn, whose correlation coefficients were -0.34 to -0.59, -0.52 to -0.74, and -0.63 to -0.70, respectively. Fertilizing NPKCaMg obtained the highest result in the uptakes of N, P, K, Ca, and Mg, which were 289.1-327.4, 25.4-29.3, 137.4-166.0, 41.9-48.9, and 39.8-43.1 kg ha -1 , respectively. Fertilizing by SSNM has increased pineapple yield by 22.9 %-44.9 % compared to the FFP. This fertilizer formula should be transferred to the local farmers in order not only to enhance productivity, but also to limit the damage of chemical fertilizers on the environment. Moreover, this formula should be tested globally in other places that share similar soil characteristics., Competing Interests: Nguyen Quoc Khuong reports financial support was provided by Hau Giang Department of Science and Technology. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Aims: Immune checkpoint inhibitors targeting PD-L1 are crucial in cancer research for preventing cancer cells from evading the immune system. Materials & methods: This study developed a screening model combining ANN, molecular similarity, and GNINA 1.0 docking to target PD-L1. A database of 2044 substances was compiled from patents. Results: For molecular similarity, the AVALON emerged as the most effective fingerprint, demonstrating an AUC-ROC of 0.963. The ANN model outperformed the Random Forest and Support Vector Classifier in cross-validation and external validation, achieving an average precision of 0.851 and an F1 score of 0.790. GNINA 1.0 was validated through redocking and retrospective control, achieving an AUC of 0.975. Conclusions: From 15235 DrugBank compounds, 22 candidates were shortlisted. Among which (3 S )-1-(4-acetylphenyl)-5-oxopyrrolidine-3-carboxylic acid emerged as the most promising.

Importance: Although the current rate of SARS-CoV-2 infections has decreased significantly, COVID-19 still ranks very high as a cause of death worldwide. As of October 2023, the weekly mortality rate is still at 600 deaths in the United States alone, which surpasses even the worst mortality rates recorded for influenza. Thus, the long-term outlook of COVID-19 is still a serious concern outlining the need for the next-generation vaccine. This study found that a prime/pull coronavirus vaccine strategy increased the frequency of functional SARS-CoV-2-specific CD4 + and CD8 + memory T cells in the lungs of SARS-CoV-2-infected triple transgenic HLA-DR*0101/HLA-A*0201/hACE2 mouse model, thereby resulting in low viral titer and reduced COVID-19-like symptoms., Competing Interests: L.B.M. has an equity interest in TechImmune, LLC, a company that may potentially benefit from the research results and serves on the company's Scientific Advisory Board. L.B.M.'s relationship with TechImmune, LLC has been reviewed and approved by the University of California, Irvine, in accordance with its conflict-of-interest policies.

UBTF tandem duplications are recurrent in adult and paediatric acute myeloid leukaemia and have been reported to be associated with a poor prognosis. Co-mutations in WT1 and FLT3 are common while morphological dysplasia is frequent. The role of UBTF-TDs in leukemogenesis is yet to be elucidated; however they have been proposed as early initiating events, making them attractive for assessment of MRD and a potential therapeutic target. We present two cases where the UBTF- TD was observed in remission and discuss the implications of these findings in the clinicobiological understanding of this emerging entity., Competing Interests: The authors have no conflict of interest to disclose., (© 2023 The Authors. eJHaem published by British Society for Haematology and John Wiley & Sons Ltd.)

Undetectable measurable residual disease (MRD) is associated with favourable clinical outcomes in chronic lymphocytic leukaemia (CLL). While assessment is commonly performed using multiparameter flow cytometry (MFC), this approach is associated with limitations including user bias and expertise that may not be widely available. Implementation of unsupervised clustering algorithms in the laboratory can address these limitations and have not been previously reported in a systematic quantitative manner. We developed a computational pipeline to assess CLL MRD using FlowSOM. In the training step, a self-organising map was generated with nodes representing the full breadth of normal immature and mature B cells along with disease immunophenotypes. This map was used to detect MRD in multiple validation cohorts containing a total of 456 samples. This included an evaluation of atypical CLL cases and samples collected from two different laboratories. Computational MRD showed high correlation with expert analysis (Pearson's r > 0.99 for typical CLL). Binary classification of typical CLL samples as either MRD positive or negative demonstrated high concordance (>98%). Interestingly, computational MRD detected disease in a small number of atypical CLL cases in which MRD was not detected by expert analysis. These results demonstrate the feasibility and value of automated MFC analysis in a diagnostic laboratory., (© 2023 British Society for Haematology and John Wiley & Sons Ltd.)

Background: Due to interconnected structural determinants including low maternal health knowledge, economic marginalization, and remoteness from low-capacity health centers, ethnic minority women in remote areas of Vietnam face severe maternal, newborn, and child health (MNCH) inequities. As ethnic minorities represent 15% of the Vietnamese population, these disparities are significant. mMOM-a pilot mobile health (mHealth) intervention using SMS text messaging to improve MNCH outcomes among ethnic minority women in northern Vietnam-was implemented from 2013-2016 with promising results. Despite mMOM's findings, exacerbated MNCH inequities, and digital health becoming more salient amid COVID-19, mHealth has not yet been scaled to address MNCH among ethnic minority women in Vietnam., Objective: We describe the protocol for adapting, expanding, and exponentially scaling the mMOM intervention qualitatively through adding COVID-19-related MNCH guidance and novel technological components (mobile app and artificial intelligence chatbots) and quantitatively through broadening the geographical area to reach exponentially more participants, within the evolving COVID-19 context., Methods: dMOM will be conducted in 4 phases. (1) Drawing on a review of international literature and government guidelines on MNCH amid COVID-19, mMOM project components will be updated to respond to COVID-19 and expanded to include a mobile app and artificial intelligence chatbots to more deeply engage participants. (2) Using an intersectionality lens and participatory action research approach, a scoping study and rapid ethnographic fieldwork will explore ethnic minority women's unmet MNCH needs; acceptability and accessibility of digital health; technical capacity of commune health centers; gendered power dynamics and cultural, geographical, and social determinants impacting health outcomes; and multilevel impacts of COVID-19. Findings will be applied to further refine the intervention. (3) dMOM will be implemented and incrementally scaled across 71 project communes. (4) dMOM will be evaluated to assess whether SMS text messaging or mobile app delivery engenders better MNCH outcomes among ethnic minority women. The documentation of lessons learned and dMOM models will be shared with Vietnam's Ministry of Health for adoption and further scaling up., Results: The dMOM study was funded by the International Development Research Centre (IDRC) in November 2021, cofacilitated by the Ministry of Health, and is being coimplemented by provincial health departments in 2 mountainous provinces. Phase 1 was initiated in May 2022, and phase 2 is planned to begin in December 2022. The study is expected to be complete in June 2025., Conclusions: dMOM research outcomes will generate important empirical evidence on the effectiveness of leveraging digital health to address intractable MNCH inequities among ethnic minority women in low-resource settings in Vietnam and provide critical information on the processes of adapting mHealth interventions to respond to COVID-19 and future pandemics. Finally, dMOM activities, models, and findings will inform a national intervention led by the Ministry of Health., International Registered Report Identifier (irrid): PRR1-10.2196/44720., (©Bronwyn McBride, John O'Neil, Phuong Chi Nguyen, Dang Thuy Linh, Hue Thi Trinh, Nguyen C Vu, Liem T Nguyen. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 24.04.2023.)

Inotodiol, an oxysterol found only in Chaga mushroom, has received attention from the pharmaceutical industry due to its strong antioxidant and anti-allergic activities. However, the production of inotodiol is still challenging, and its fundamental properties have yet to be investigated. This study aims to develop an efficient method to produce high-purity inotodiol from Chaga mushroom. Then, pure inotodiol was used to assess its physicochemical properties and biological activities. By optimizing the solvent used for extraction and purification, a new method to produce inotodiol was developed with high purity (>97%) and purification yield (33.6%). Inotodiol exhibited a melting point (192.06 °C) much higher than lanosterol and cholesterol. However, the solubility of inotodiol in organic solvents was notably lower than those of the other two sterols. The difference in the hydroxyl group at C-22 of inotodiol has shown the distinctive physicochemical properties of inotodiol compared with cholesterol and lanosterol. Based on those findings, a nonionic surfactant-based delivery system for inotodiol was developed to improve its bioavailability. The inotodiol microemulsion prepared with 1-2% Tween-80 exhibited homogenous droplets with an acceptable diameter (354 to 217 nm) and encapsulation efficiency (85.6-86.9%). The pharmacokinetic analysis of inotodiol microemulsion in oral administration of 4.5 mg/kg exhibited AUC 0-24h = 341.81 (ng·h/mL), and C max = 88.05 (ng/mL). Notably, when the dose increased from 4.5 to 8.0 mg/kg, the bioavailability of inotodiol decreased from 41.32% to 33.28%. In a mouse model of sepsis, the serum level of interleukin-6 significantly decreased, and the rectal temperature of mice was recovered in the inotodiol emulsion group, indicating that inotodiol microemulsion is an effective oral delivery method. These results could provide valuable information for applying inotodiol in functional food, cosmetic, and pharmaceutical industries.

The role of upfront non-myeloablative allogeneic stem cell transplantation (NMA alloSCT) in high-risk multiple myeloma (HR-MM) is unclear. We evaluated outcomes of NMA alloSCT following autologous stem cell transplant (ASCT) compared with ASCT alone for newly diagnosed HR-MM. Two-year progression-free survival was improved in the ASCT-NMA alloSCT group (44% vs 16%; P = 0.035), with a trend for improved overall survival (P = 0.118). These results suggest that ASCT-NMA alloSCT can be considered as upfront therapy in HR-MM., (© 2022 The Authors. Internal Medicine Journal published by John Wiley & Sons Australia, Ltd on behalf of Royal Australasian College of Physicians.)

The one-step synthesis of glycogen-type polysaccharides from maltooctaose (G8) was accomplished based on the new findings of the catalytic mechanism of glycogen branching enzymes (GBEs) from Vibrio vulnificus, Deinococcus geothermalis, and Escherichia coli. GBEs from D. geothermalis and E. coli used maltononaose and maltotridecaose as the minimum, respectively, while V. vulnificus GBE (VvGBE) catalyzed the surprisingly small substrate, G8, into polysaccharides. Intriguingly, all three GBEs catalyzed α-1,4-transglycosylation at the early reaction stage of transglycosylation. VvGBE successfully converted the smallest substrate (G8) into two highly branched polysaccharides (HBP), in which the big polysaccharide (1.49 × 10 5  Da) exhibited structural properties similar to glycogen. Both HBPs had similar side chain distribution with a very short average degree of polymerization compared with mussel glycogen. As a molecular biology reagent, these nucleotide-free HBPs significantly increased the mRNA extraction efficiency of mammalian cells. Our results provide a new approach to the synthesis of novel polysaccharides., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This paper compiles the data associated with a research article published in STOTEN [1]. The data set represents figures, tables, and images illustrating the temporal and spatial distribution of land use and flood dynamics from 2000 to 2020 in the Vietnamese Mekong Delta (VMD). The MODIS imageries were freely accessed online via the NASA website [2] and processed to land use and flood maps based on the algorithms by Sakamoto et al. [3,4]. The MODIS products show a high validation with statistical data and radar satellites [1]. The datasets of flood map and land use, therefore, are available to scientists, engineers, and policy-makers in agricultural management associated with flood management in the VMD. They could be used for policy settings, household livelihood assessment as well as other economic analyses for the VMD region due to the change of land use and flooding dynamics., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article., (© 2022 The Authors. Published by Elsevier Inc.)

Background: Improving treatment outcomes for multidrug-resistant tuberculosis (MDR-TB) is a leading priority for global TB control. This retrospective cohort study evaluated the factors associated with treatment success among patients treated for MDR-TB in two provinces in Vietnam., Methods: Treatment outcomes were evaluated for adult patients treated in Hanoi and Thanh Hoa provinces between 2014 and 2016. The primary outcome was the proportion of patients with treatment success, defined as cure or treatment completion. Logistic regression analysis was used to evaluate the relationship between patient clinical and microbiological characteristics and treatment success., Results: Treatment outcomes were reported in 612 of 662 patients; of these, 401 (65.5)% were successfully treated. The odds of treatment success were lower for male patients (aOR 0.56, 95% CI 0.34-0.90), for people living with HIV (aOR 0.44, 95% CI 0.20-1.00), and for patients treated for extensive antibiotic resistance (pre-XDR-/XDT-TB) (aOR 0.53, 95% CI 0.29-0.97), compared with others. Patients who achieved culture conversion in the first 4 months of treatment had increased odds (aOR 2.93, 95% CI 1.33-6.45) of treatment success. In addition, loss to follow-up was less common among patients covered by social health insurance compared to those who paid for treatment out-of-pocket (aOR 0.55, 95% CI 0.32-0.95)., Conclusions: Among patients with MDR-TB, males, people living with HIV, and those with more extensive antibiotic resistance at diagnosis are at greatest risk of an unsuccessful treatment outcome. Efforts to optimise the management of co-morbidities (such as HIV), ensure rapid bacteriological conversion, and provide financial support for patients promise to improve treatment outcomes., (© 2022. The Author(s).)

The benefits of non-myeloablative stem cell transplant in older patients with acute myeloid leukaemia are unclear. We compare the long-term outcomes of this regimen in those aged 55-65 years in first remission with a chemotherapy only cohort that achieved durable morphologic remission. Five-year overall survival was similar (32% vs 33%, P = 0.90), as was relapse-free survival (23% vs 20%, P = 0.37). There was a trend for decreased relapse that was balanced against increased non-relapse mortality with transplantation., (© 2021 Royal Australasian College of Physicians.)

Central pontine myelinolysis (CPM) is commonly associated with osmotic stress and rapid correction of hyponatraemia. It has rarely been reported in conjunction with malignancies. We report a case where CPM was not only associated with a new diagnosis of diffuse large B-cell lymphoma but was also a key presenting feature., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

This study presents a simple, efficient, accurate method for nonlinear time-history earthquake analysis of spatial steel frames. The proposed new fiber plastic hinge method simulating only one element for each member captures the time-history dynamic behavior of steel frames as accurately as sophisticated plastic zone methods. Stability functions and the geometric stiffness matrix are employed for predicting the second-order effects that aim to minimize computational time and computer resources. Residual stresses are considered through two fiber plastic hinges by assigning initial stress values. A numerical integration procedure using Newmark integration combined with the Newton-Raphson balanced iteration algorithm is developed to find a solution to nonlinear dynamic equilibrium equations of the structural system. Shear deformation effects are also considered in the dynamic analysis. The proposed software, named Direct Advanced Analysis and Design (DAAD), is proved to be accurate and reliable as compared with the analysis results generated by expensive commercial Finite Element Analysis (FEA) software packages. The proposed DAAD program can be improved for performance-based direct design and analysis., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

A novel maltoheptaose-palmitate ester (G7-PA) was synthesized and investigated for emulsion properties. First of all, the optimal conditions for lipase-catalyzed G7-PA synthesis, which were 0.2 of the G7/PA molar ratio, 33.5 U of immobilized CALB per 1 g of PA in 10% DMSO, were determined by response surface methodology. G7-PA was compared with the commercial sucrose-PA (S-PA) in terms of emulsion-forming ability and stability at extreme conditions. At the 0.1% surfactant concentration, G7-PA emulsion exhibited a droplet distribution similar to the 0.2% surfactant condition, while S-PA emulsion was quickly destabilized. G7-PA showed better emulsifying properties than the S-PA at the acidic condition (pH 3). Flocculation and phase separation was observed at the S-PA emulsion, but the G7-PA emulsion was stable for 7-day. In thermostability tests, G7-PA and S-PA both were stable up to the boiling temperature. Conclusively, G7-PA exhibits excellent properties as a biosurfactant in O/W emulsion compared with S-PA., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Submassive pulmonary embolism (PE) lies on a spectrum of disease severity between standard and high-risk disease. By definition, patients with submassive PE have a worse outcome than the majority of those with standard-risk PE, who are hemodynamically stable and lack imaging or laboratory features of cardiac dysfunction. Systemic thrombolytic therapy has been proven to reduce mortality in patients with high-risk disease; however, its use in submassive PE has not demonstrated a clear benefit, with haemodynamic improvements being offset by excess bleeding. Furthermore, meta-analyses have been confusing, with conflicting results on overall survival and net gain. As such, significant interest remains in optimising thrombolysis, with recent efforts in catheter-based delivery as well as upcoming studies on reduced systemic dosing. Recently, long-term cardiorespiratory limitations following submassive PE have been described, termed post-PE syndrome. Studies on the ability of thrombolytic therapy to prevent this condition also present conflicting evidence. In this review, we aim to clarify the current evidence with respect to submassive PE management, and also to highlight shortcomings in current definitions and prognostic factors. Additionally, we discuss novel therapies currently in preclinical and early clinical trials that may improve outcomes in patients with submassive PE.

In this study, maltoheptaose (G7)-based sugar esters were synthesized from maltoheptaose and fatty acids (C10-C16) using a commercial lipase. With the exception of dimethyl sulfoxide (DMSO; 76.4%, w/v), G7 showed only limited solubility in organic solvents. Among the fatty acids, palmitic acid (PA) was the best substrate for G7-based ester formation. G7-PA ester was successfully synthesized as the monoester structure exclusively in 10% DMSO of t-butanol with a 22% conversion yield. NMR and enzymatic analyses of the purified monoester product revealed that the ester bond in the G7 was located at C-6 of the glucose at the reducing end. The G7-PA monoester showed the melting temperature at 56.3 °C that was 6.5 °C lower than that of the free PA and exhibited a different endothermic pattern from the free G7. The G7-PA monoester exhibited excellent emulsifier potential with more even droplet size distribution compared with the commercial sucrose esters for an oil-in-water emulsion system., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

With the high number of patients infected by tuberculosis and the sharp increase of drug-resistant tuberculosis cases, developing new drugs to fight this disease has become increasingly urgent. In this context, analogs of the naturally occurring enolphosphates Cyclipostins and Cyclophostin (CyC analogs) offer new therapeutic opportunities. The CyC analogs display potent activity both in vitro and in infected macrophages against several pathogenic mycobacteria including Mycobacterium tuberculosis and Mycobacterium abscessus. Interestingly, these CyC inhibitors target several enzymes with active-site serine or cysteine residues that play key roles in mycobacterial lipid and cell wall metabolism. Among them, TesA, a putative thioesterase involved in the synthesis of phthiocerol dimycocerosates (PDIMs) and phenolic glycolipids (PGLs), has been identified. These two lipids (PDIM and PGL) are non-covalently bound to the outer cell wall in several human pathogenic mycobacteria and are important virulence factors. Herein, we used biochemical and structural approaches to validate TesA as an effective pharmacological target of the CyC analogs. We confirmed both thioesterase and esterase activities of TesA, and showed that the most active inhibitor CyC 17 binds covalently to the catalytic Ser104 residue leading to a total loss of enzyme activity. These data were supported by the X-ray structure, obtained at a 2.6-Å resolution, of a complex in which CyC 17 is bound to TesA. Our study provides evidence that CyC 17 inhibits the activity of TesA, thus paving the way to a new strategy for impairing the PDIM and PGL biosynthesis, potentially decreasing the virulence of associated mycobacterial species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A set of 19 oxadiazolone (OX) derivatives have been investigated for their antimycobacterial activity against two pathogenic slow-growing mycobacteria, Mycobacterium marinum and Mycobacterium bovis BCG, and the avirulent Mycobacterium tuberculosis (M. tb) mc 2 6230. The encouraging minimal inhibitory concentrations (MIC) values obtained prompted us to test them against virulent M. tb H37Rv growth either in broth medium or inside macrophages. The OX compounds displayed a diversity of action and were found to act either on extracellular M. tb growth only with moderated MIC 50 , or both intracellularly on infected macrophages as well as extracellularly on bacterial growth. Of interest, all OX derivatives exhibited very low toxicity towards host macrophages. Among the six potential OXs identified, HPOX, a selective inhibitor of extracellular M. tb growth, was selected and further used in a competitive labelling/enrichment assay against the activity-based probe Desthiobiotin-FP, in order to identify its putative target(s). This approach, combined with mass spectrometry, identified 18 potential candidates, all being serine or cysteine enzymes involved in M. tb lipid metabolism and/or in cell wall biosynthesis. Among them, Ag85A, CaeA, TesA, KasA and MetA have been reported as essential for in vitro growth of M. tb and/or its survival and persistence inside macrophages. Overall, our findings support the assumption that OX derivatives may represent a novel class of multi-target inhibitors leading to the arrest of M. tb growth through a cumulative inhibition of a large number of Ser- and Cys-containing enzymes involved in various important physiological processes., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The progression of mycobacterial diseases requires the development of new therapeutics. This study evaluated the efficacy and selectivity of a panel of Cyclophostin and Cyclipostins analogues (CyCs) against various bacteria and mycobacteria. The activity 26 CyCs was first assayed by the agar plate method. Compounds exhibiting 50-100% growth inhibition were then selected to determine their minimum inhibitory concentrations (MICs) by the resazurin microtiter assay (REMA). The best drug candidate was further tested against clinical mycobacterial isolates and bacteria responsible for nosocomial infections, including 6 Gram-negative bacteria, 5 Gram-positive bacteria, 29 rapid-growing mycobacteria belonging to the Mycobacterium chelonae-abscessus clade and 3 slow-growing mycobacteria (Mycobacterium marinum, Mycobacterium bovis BCG and Mycobacterium tuberculosis). Among the 26 CyCs tested, 10 were active and their inhibitory activity was exclusively restricted to mycobacteria. The best candidate (CyC 17 ) was further tested against 26 clinical strains and showed high selectivity for mycobacteria, with MICs (<2-40 µg/mL) comparable with those of most classical antimicrobials used to treat M. abscessus infections. Together, these results support the fact that such CyCs represent a new family of potent and selective inhibitors against mycobacteria. This is of particular interest for future chemotherapeutic developments against mycobacterial-associated infections, especially against M. abscessus, the most drug-resistant mycobacterial species., (Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.)

An increasing prevalence of cases of drug-resistant tuberculosis requires the development of more efficacious chemotherapies. We previously reported the discovery of a new class of cyclipostins and cyclophostin (CyC) analogs exhibiting potent activity against Mycobacterium tuberculosis both in vitro and in infected macrophages. Competitive labeling/enrichment assays combined with MS have identified several serine or cysteine enzymes in lipid and cell wall metabolism as putative targets of these CyC compounds. These targets included members of the antigen 85 (Ag85) complex ( i.e. Ag85A, Ag85B, and Ag85C), responsible for biosynthesis of trehalose dimycolate and mycolylation of arabinogalactan. Herein, we used biochemical and structural approaches to validate the Ag85 complex as a pharmacological target of the CyC analogs. We found that CyC 7β , CyC 8β , and CyC 17 bind covalently to the catalytic Ser 124 residue in Ag85C; inhibit mycolyltransferase activity ( i.e. the transfer of a fatty acid molecule onto trehalose); and reduce triacylglycerol synthase activity, a property previously attributed to Ag85A. Supporting these results, an X-ray structure of Ag85C in complex with CyC 8β disclosed that this inhibitor occupies Ag85C's substrate-binding pocket. Importantly, metabolic labeling of M. tuberculosis cultures revealed that the CyC compounds impair both trehalose dimycolate synthesis and mycolylation of arabinogalactan. Overall, our study provides compelling evidence that CyC analogs can inhibit the activity of the Ag85 complex in vitro and in mycobacteria, opening the door to a new strategy for inhibiting Ag85. The high-resolution crystal structure obtained will further guide the rational optimization of new CyC scaffolds with greater specificity and potency against M. tuberculosis ., (© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.)

A new class of Cyclophostin and Cyclipostins (CyC) analogs have been investigated against Mycobacterium tuberculosis H37Rv (M. tb) grown either in broth medium or inside macrophages. Our compounds displayed a diversity of action by acting either on extracellular M. tb bacterial growth only, or both intracellularly on infected macrophages as well as extracellularly on bacterial growth with very low toxicity towards host macrophages. Among the eight potential CyCs identified, CyC 17 exhibited the best extracellular antitubercular activity (MIC 50  = 500 nM). This compound was selected and further used in a competitive labelling/enrichment assay against the activity-based probe Desthiobiotin-FP in order to identify its putative target(s). This approach, combined with mass spectrometry, identified 23 potential candidates, most of them being serine or cysteine enzymes involved in M. tb lipid metabolism and/or in cell wall biosynthesis. Among them, Ag85A, CaeA and HsaD, have previously been reported as essential for in vitro growth of M. tb and/or survival and persistence in macrophages. Overall, our findings support the assumption that CyC 17 may thus represent a novel class of multi-target inhibitor leading to the arrest of M. tb growth through a cumulative inhibition of a large number of Ser- and Cys-containing enzymes participating in important physiological processes.

The development of neutralizing anti-factor VIII (FVIII) antibodies complicates the treatment of many hemophilia A patients. The C-terminal C2 domain is a particularly antigenic FVIII region. A crystal structure of recombinant FVIII-C2 bound to an Fab fragment of the patient-derived monoclonal antibody BO2C11, which recognizes an immunodominant inhibitor epitope on FVIII and blocks its ability to bind von Willebrand factor (VWF) and phospholipids, revealed that 15 amino acids in FVIII contact this antibody. Forty-three recombinant FVIII-C2 proteins, each with a surface-exposed side chain mutated to alanine or another residue, were generated, and surface plasmon resonance studies were carried out to evaluate effects of these substitutions on BO2C11/FVIII-C2 binding affinity. Thermodynamic analysis of experiments carried out at three temperatures indicated that one beta hairpin turn at the antigen-antibody interface (FVIII-F2196, N2198, M2199 and F2200) plus two non-contiguous arginines (FVIII-R2215 and R2220), contributed appreciably to the affinity. B-domain-deleted (BDD) FVIII-F2196A, FVIII-F2196K and FVIII-M2199A were generated and characterized. Their pro-coagulant activities and binding to VWF were similar to those of WT-BDD-FVIII, and FVIII-F2196K avoided neutralization by BO2C11 and murine inhibitory mAb 1B5. This study suggests specific sites for amino acid substitutions to rationally design FVIII variants capable of evading immunodominant neutralizing anti-FVIII antibodies.

Neutralizing anti-factor VIII (FVIII) antibodies that develop in patients with hemophilia A and in murine hemophilia A models, clinically termed "inhibitors," bind to several distinct surfaces on the FVIII-C2 domain. To map these epitopes at high resolution, 60 recombinant FVIII-C2 proteins were generated, each having a single surface-exposed residue mutated to alanine or a conservative substitution. The binding kinetics of these muteins to 11 monoclonal, inhibitory anti-FVIII-C2 antibodies were evaluated by surface plasmon resonance and the results compared with those obtained for wild-type FVIII-C2. Clusters of residues with significantly altered binding kinetics identified "functional" B-cell epitopes, defined as those residues contributing appreciable antigen-antibody avidity. These antibodies were previously shown to neutralize FVIII activity by interfering with proteolytic activation of FVIII by thrombin or factor Xa, or with its binding to phospholipid surfaces, von Willebrand factor, or other components of the intrinsic tenase complex. Fine mapping of epitopes by surface plasmon resonance also indicated surfaces through which FVIII interacts with proteins and phospholipids as it participates in coagulation. Mutations that significantly altered the dissociation times/half-lives identified functionally important interactions within antigen-antibody interfaces and suggested specific sequence modifications to generate novel, less antigenic FVIII proteins with possible therapeutic potential for treatment of inhibitor patients.

Described is an engineered metal-binding protein, MBPPhen2, which forms porous crystalline frameworks that feature coordinatively unsaturated Zn- and Ni-centers.

The ability to orient active proteins on surfaces is a critical aspect of many medical technologies. An important related challenge is characterizing protein orientation in these surface films. This study uses a combination of time-of-flight secondary ion mass spectrometry (ToF-SIMS), sum frequency generation (SFG) vibrational spectroscopy, and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy to characterize the orientation of surface-immobilized Protein G B1, a rigid 6 kDa domain that binds the Fc fragment of IgG. Two Protein G B1 variants with a single cysteine introduced at either end were immobilized via the cysteine thiol onto maleimide-oligo(ethylene glycol)-functionalized gold and bare gold substrates. X-ray photoelectron spectroscopy was used to measure the amount of immobilized protein, and ToF-SIMS was used to measure the amino acid composition of the exposed surface of the protein films and to confirm covalent attachment of protein thiol to the substrate maleimide groups. SFG and NEXAFS were used to characterize the ordering and orientation of peptide or side chain bonds. On both substrates and for both cysteine positions, ToF-SIMS data showed enrichment of mass peaks from amino acids located at the end of the protein opposite to the cysteine surface position as compared with nonspecifically immobilized protein, indicating end-on protein orientations. Orientation on the maleimide substrate was enhanced by increasing pH (7.0-9.5) and salt concentration (0-1.5 M NaCl). SFG spectral peaks characteristic of ordered α-helix and β-sheet elements were observed for both variants but not for cysteine-free wild type protein on the maleimide surface. The phase of the α-helix and β-sheet peaks indicated a predominantly upright orientation for both variants, consistent with an end-on protein binding configuration. Polarization dependence of the NEXAFS signal from the N 1s to π* transition of β-sheet peptide bonds also indicated protein ordering, with an estimated tilt angle of inner β-strands of 40-50° for both variants (one variant more tilted than the other), consistent with SFG results. The combined results demonstrate the power of using complementary techniques to probe protein orientation on surfaces.

We report here the construction of phenanthroline (Phen) and terpyridine (Terpy)-based hybrid coordination motifs (HCMs), which were installed on the surface of the four-helical bundle hemeprotein cytochrome cb(562). The resulting constructs, termed HPhen1, HPhen2, HPhen3, and HTerpy1, feature HCMs that are composed of a histidine ligand and a Phen or Terpy functionality located two helix turns away, yielding stable tri- or tetradentate coordination platforms. Our characterization of the tridentate HCMs indicates that they accommodate many divalent metal ions (Co(2+), Ni(2+), Cu(2+), Zn(2+)) with nanomolar to femtomolar affinities, lead to significant stabilization of the alpha-helical protein scaffold through metal-mediated cross-linking, assert tight control over protein dimerization, and provide stable and high-affinity binding sites for substitution-inert metal probes. Our analyses suggest that such tridentate HCMs may be used modularly on any alpha-helical protein surface in a sequence-independent fashion.

Protein homodimerization is the simplest form of oligomerization that is frequently utilized for the construction of functional biological assemblies and the regulation of cellular pathways. Despite its simplicity, dimerization still poses an enormous challenge for protein engineering and chemical manipulation, owing to the large molecular surfaces involved in this process. We report here the construction of a hybrid coordination motif--consisting of a natural (His) and a non-natural ligand (quinolate)--on the alpha-helical surface of cytochrome cb(562), which (a) simultaneously binds divalent metals with high affinity, (b) leads to a metal-induced increase in global protein stability, and importantly, (c) enables the formation of a discrete protein dimer, whose shape is dictated by the inner-sphere metal coordination geometry and closely approximates that of the DNA-binding domains of bZIP family transcription factors.

Bioactive polymers bearing sulfonate (styrene sodium sulfonate, NaSS) and carboxylate (methylacrylic acid, MA) groups were grafted onto Ti6Al4V alloy surfaces by a two-step procedure. The Ti alloy surfaces were first chemically oxidized in a piranha solution and then directly subjected to radical polymerization at 70 degrees C in the absence of oxygen. The grafted surfaces were characterized by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and the toluidine blue colorimetric method. Toluidine blue results showed 1-5microgcm(-2) of polymer was grafted onto the oxidized Ti surfaces. Grafting resulted in a decrease in the XPS Ti and O signals from the underlying Ti substrate and a corresponding increase in the XPS C and S signals from the polymer layer. The ToF-SIMS intensities of the S(-) and SO(-) ions correlated linearly with the XPS atomic percent S concentrations and the ToF-SIMS intensity of the TiO(3)H(2)(-) ion correlated linearly with the XPS atomic per cent Ti concentration. Thus, the ToF-SIMS S(-), SO(-) and TiO(3)H(2)(-) intensities can be used to quantify the composition and amount of grafted polymer. ToF-SIMS also detected ions that were more characteristic of the polymer molecular structure (C(6)H(4)SO(3)(-) and C(8)H(7)SO(3)(-) from NaSS, C(4)H(5)O(2)(-) from MA), but the intensity of these peaks depended on the polymer thickness and composition. An in vitro cell culture test was carried out with human osteoblast-like cells to assess the influence of the grafted polymers on cell response. Cell adhesion after 30min of incubation showed significant differences between the grafted and ungrafted surfaces. The NaSS grafted surfaces showed the highest degree of cell adhesion while the MA-NaSS grafted surfaces showed the lowest degree of cell adhesion. After 4 weeks in vivo in rabbit femoral bones, bone was observed to be in direct contact with all implants. The percentage of mineralized tissue around the implants was similar for NaSS grafted and non-grafted implants (59% and 57%). The MA-NaSS grafted implant exhibited a lower amount of mineralized tissue (47%).

The surface structure and DNA hybridization performance of thiolated single-strand DNA (HS-ssDNA) covalently attached to a maleimide-ethylene glycol disulfide (MEG) monolayer on gold have been investigated. Monolayer immobilization chemistry and surface coverage of reactive ssDNA probes were studied by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. Orientation of the ssDNA probes was determined by near-edge X-ray absorption fine structure (NEXAFS). Target DNA hybridization on the DNA-MEG probe surfaces was measured by surface plasmon resonance (SPR) to demonstrate the utility of these probe surfaces for detection of DNA targets from both purified target DNA samples and complex biological mixtures such as blood serum. Data from complementary techniques showed that immobilized ssDNA density is strongly dependent on the spotted bulk DNA concentration and buffer ionic strength. Variation of the immobilized ssDNA density had a profound influence on the DNA probe orientation at the surface and subsequent target hybridization efficiency. With increasing surface probe density, NEXAFS polarization dependence results (followed by monitoring the N 1s --> pi* transition) indicate that the immobilized ssDNA molecules reorient toward a more upright position on the MEG monolayer. SPR assays of DNA targets from buffer and serum showed that DNA hybridization efficiency increased with decreasing surface probe density. However, target detection in serum was better on the "high-density" probe surface than on the "high-efficiency" probe surface. The amounts of target detected for both ssDNA surfaces were several orders of magnitude poorer in serum than in purified DNA samples due to nonspecific serum protein adsorption onto the sensing surface.

In a previous placebo-controlled, randomized, double-blind, cross-over study performed in 6 healthy volunteers, we investigated the pharmacokinetics and pharmacodynamics of a single oral administration of two doses (5 and 20 mg) of the angiotensin-converting enzyme inhibitor (ACEI), lisinopril. The purpose of the present study was to investigate the relation between lisinopril plasma concentrations (C, ng/ml), and lisinopril-induced effects on plasma converting enzyme activity (PCEA, nmol/ml/min), brachial artery flow (BAF, ml/min), and brachial vascular resistance (BVR, mm Hg . s/ml). PCEA and BVR were expressed in percent changes from initial values and BAF was expressed in absolute values. Effects (E) were related to C by the Hill model: E = Emax . C gamma/CE50 gamma + C gamma). For PCEA, the model was fitted to the data of both doses simultaneously. Emax was fixed at -100%, and we obtained (mean +/- SD) CE50 = 1.4 +/- 0.6 ng/ml and gamma = 0.6 +/- 0.1. For BAF and BVR, the model was fitted to the data of the 20-mg dose for 5 subjects and to those of the 5-mg dose for 1 subject. We obtained Emax = 45 +/- 20 ml/min, CE50 = 24.0 +/- 12.4 ng/ml, and gamma = 3.2 +/- 1.3 for BAF, and Emax = -45 +/- 15%, CE50 = 22.0 +/- 10.2 ng/ml, and gamma = 3.1 +/- 1.1 for BVR. Therefore, the concentration-effect relations for BVR (or BAF) and PCEA display quite different shapes (CE50, gamma), which emphasizes the necessity of performing pharmacokinetic-pharmacodynamic (PK-PD) modeling on hemodynamic parameters to determine the optimal dosages of ACEIs.

We adapt a recent model from the Framingham study (Circulation 1991; 83: 356-362) to predict CHD in France for both sexes over a large age range. Calculations were based on data from the French PCV-METRA study. In France, the Paris Prospective Study model could predict CHD but only for men aged 43-53 years. Applied to men 43-53 years from the PCV-METRA, the Framingham model estimated a 5-year CHD risk (4%) lower than the risk reported in the Framingham sample, but significantly higher than the risk estimated by the French model (2%). Differences in estimated CHD risk between the Framingham and the PCV-METRA samples were explained for only 30% by adjustment on major CHD risk factors (mainly HDL-cholesterol and tobacco). Modifying the intercept in the Framingham model, agreement with estimated risk by the French model was improved from 29 to 80%. By an appropriate change of the intercept, the Framingham model might be used to estimate CHD risk in other populations.

Brachial and carotid artery diameters, blood velocities and blood flows were determined by a pulsed-Doppler flowmeter in 22 normotensive and 74 mild to moderate essential hypertensive subjects, aged 46 +/- 8 years. The product age x MAP/1000 (where MAP is mean arterial blood pressure), called 'arterial age' (expressed in years x mmHg/1000), was used to assess the progress of age and blood pressure. The moving-mean method was first used to explore the chronic hemodynamic changes in the two circulations with a progressive increase in arterial age. The method indicated that an arterial age of about 4-4.5 units a noticeable decrease in both brachial and carotid blood velocities occurred, and at an arterial age of about 5 units an important increase in brachial artery diameter occurred. In order to test these findings, the total sample (n = 96) was divided into three groups of equal size with low, median and high arterial ages. Brachial blood velocity decreased significantly in groups 2 (P less than 0.05) and 3 (P less than 0.05) compared with group 1, and carotid blood velocity decreased significantly from group 1 to group 2 (P less than 0.02) and from group 2 to group 3 (P less than 0.05). Brachial artery diameter did not change from group 1 to group 2, but increased significantly from group 2 to group 3 (P less than 0.05). Over the whole arterial age range, the carotid artery diameter remained identical.(ABSTRACT TRUNCATED AT 250 WORDS)

We studied the effect of the control of the hypothyroid state in humans on the pharmacokinetic parameters of cefazolin and gentamicin after a single intravenous injection. These two antibiotics were chosen because of their different patterns of binding to serum albumin (0% for gentamicin and 82% for cefazolin). In hypothyroidism, the behavior of cefazolin only was altered, with a decrease in the total body clearance, possibly due to reduced urinary excretion, and a decrease in the volume of distribution without a significant alteration of cefazolin binding to serum protein.