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Introduction: In France March 14, 2020 a national lockdown was imposed in France for 55 days to prevent the spread of COVID-19 and all schools were closed. This study aimed to investigate the effects of home confinement as a result of  lockdown on the activity (physical activity and sedentary behaviors), and their determinants, on French children (6-10 years) and adolescents (11-17 years)., Methods: The National Observatory for Physical Activity and Sedentary behaviors launched an online survey from April 1 st , to May 6 th , 2020 using popular social networks and websites. It compared the level of physical activity (PA), sitting and screen time before and during the lockdown and identified the impact of the initial PA (active vs. inactive), sedentary (high vs. low) profiles of the participants and their housing conditions., Results: 6,491 children were included in this study. Initially active children and adolescents decreased their PA more than those initially inactive (p>0.001), while those who met the sitting time recommendations increased more their sitting time during lockdown (p<0.001). The same applied to screen time (p<0.001). Living in an urban environment was associated with a decrease in PA (p<0.001), an increase in sitting time (p<0.001) and children's screen time (p=0.002) during lockdown., Conclusion: This study showed the deleterious effects of confinement caused by lockdown on physical activity and sedentary behaviors. Housing conditions were associated with lifestyle behaviors over this period of lockdown. Future public health policies should consider these results., Competing Interests: 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., (© 2021 Elsevier GmbH. All rights reserved.)

CLC-2 is a voltage-gated chloride channel that is widely expressed in mammalian tissues. In the central nervous system, CLC-2 appears in neurons and glia. Studies to define how this channel contributes to normal and pathophysiological function in the central nervous system raise questions that remain unresolved, in part due to the absence of precise pharmacological tools for modulating CLC-2 activity. Herein, we describe the development and optimization of AK-42, a specific small-molecule inhibitor of CLC-2 with nanomolar potency (IC 50 = 17 ± 1 nM). AK-42 displays unprecedented selectivity (>1,000-fold) over CLC-1, the closest CLC-2 homolog, and exhibits no off-target engagement against a panel of 61 common channels, receptors, and transporters expressed in brain tissue. Computational docking, validated by mutagenesis and kinetic studies, indicates that AK-42 binds to an extracellular vestibule above the channel pore. In electrophysiological recordings of mouse CA1 hippocampal pyramidal neurons, AK-42 acutely and reversibly inhibits CLC-2 currents; no effect on current is observed on brain slices taken from CLC-2 knockout mice. These results establish AK-42 as a powerful tool for investigating CLC-2 neurophysiology., Competing Interests: Competing interest statement: A.K.K., J.D.B., and M.M. have filed for a patent “Compositions and Methods to Modulate Chloride Ion Channel Activity,” USSN 16/449,021 from the U.S. Patent & Trademark Office, January 16, 2020.

Background and Purpose: In patients with spinal muscular atrophy (SMA), functional disease scores are frequently used to evaluate the course of the disease and the efficacy of treatment. The aim of the present study was to propose minimal clinically important difference (MCID) values for motor scores in order to estimate the degree of change within a functional score that can be considered clinically meaningful., Methods: To estimate the MCID, distribution-based approaches were used. For each assessment [Revised Upper Limb Module (RULM), Hammersmith Functional Motor Scale Expanded (HFMSE) and 6-min walk test (6MWT)] and subgroup (SMA type 2, SMA type 3, ambulatory and non-ambulatory), the following MCID values based on a cohort of 51 adults with SMA were calculated: standard error of measurement (SEm), one-half of standard deviation (1/2 SD) and one-third of standard deviation (1/3 SD) of patients' baseline scores., Results: For the overall cohort, the SEm, 1/2 SD and 1/3 SD MCID values were 2.9, 6.4 and 4.3 for the RULM and 4.3, 10.6 and 7.0 for the HFMSE, respectively. Subgroup analysis led to generally lower standard deviations and consecutively lower MCID values due to the significantly different motor functions of the groups. The respective MCID values for the 6MWT were 55.5 m, 71.1 m and 47.8 m., Conclusions: Our data provide MCID values for functional motor scores commonly used in adults with SMA in order to distinguish statistical effects from 'real' changes. A complementary systematic consensus process could help to further adjust the MCID values we propose., (© 2020 European Academy of Neurology.)

Background: In our modern society, physical activity (PA) is decreasing and sedentary time (ST) is increasing, especially for children from disadvantaged neighborhoods. School-based interventions to promote PA and decrease ST are therefore required among this population in order to change children's lifestyle habits. Moreover, attentional capacities and academic achievement can be enhanced by chronic PA during childhood. The relationships between these variables have been poorly studied with this population., Objective: The objective of this study is to present the rationale and methods for a randomized controlled trial among 6-10-year-old children with low socioeconomic status that will (1) evaluate the effectiveness of a school-based intervention designed to promote PA and reduce ST and (2) study the relationships between PA, ST, motor skills, attentional capacities, and academic achievement., Methods: A randomized controlled trial was conducted in 2 eligible primary schools. During academic year 2016-2017, 1 school was randomly assigned as the experiment one and the other was assigned as the control one. Five assessments times were used: baseline (T1 [November 2016] to T2 [June 2017]), follow-up (T3 [November 2017] to T4 [June 2018]), and final assessment (T5 [June 2019]). The school-based intervention included various components on different levels of the socioecological model: (1) curriculum-based program for children; (2) sensitization workshops and newsletters for parents; (3) training workshops for teachers; (4) environmental adaptation of playgrounds and reorganization of recess time; (5) time adaptation of lunch breaks; and (6) collaboration with political groups. PA, ST, motor skills, and attentional capacities were evaluated and academic achievement was recorded., Results: The presented intervention and its different assessments have been successfully implemented. In order to achieve the 2 objectives of this randomized controlled trial, data analyses are about to be completed., Conclusions: The implementation of this randomized controlled trial can help to determine effective strategies to promote PA in the context of increasing prevalence of physical inactivity among children with sedentary lifestyle which will be useful for researchers, stakeholders, and public policy makers., Trial Registration: ClinicalTrials.gov NCT03983447; https://clinicaltrials.gov/ct2/show/NCT03983447., International Registered Report Identifier (irrid): RR1-10.2196/17815., (©Caroline Maite Marie Bernal, Lena Lhuisset, Nicolas Fabre, Julien Bois. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 23.09.2020.)

The development of an electrochemically driven, ruthenium-catalyzed C-H hydroxylation reaction of amine-derived substrates bearing tertiary C-H bonds is described. The reaction is performed under constant current electrolysis in a divided cell to afford alcohol products in yields comparable to those of our previously reported process, which requires the use of stoichiometric H 5 IO 6 for catalytic turnover. With aqueous acid as solvent, the cathodic electrode reaction simply involves the reduction of protons to evolve hydrogen gas. The optimized protocol offers a convenient, efficient, and atom-economical method for sp 3 -C-H bond oxidation.

The voltage-gated sodium channel isoform Na V 1.7 is highly expressed in dorsal root ganglion neurons and is obligatory for nociceptive signal transmission. Genetic gain-of-function and loss-of-function Na V 1.7 mutations have been identified in select individuals, and are associated with episodic extreme pain disorders and insensitivity to pain, respectively. These findings implicate Na V 1.7 as a key pharmacotherapeutic target for the treatment of pain. While several small molecules targeting Na V 1.7 have been advanced to clinical development, no Na V 1.7-selective compound has shown convincing efficacy in clinical pain applications. Here we describe the discovery and characterization of ST-2262, a Na V 1.7 inhibitor that blocks the extracellular vestibule of the channel with an IC 50 of 72 nM and greater than 200-fold selectivity over off-target sodium channel isoforms, Na V 1.1-1.6 and Na V 1.8. In contrast to other Na V 1.7 inhibitors that preferentially inhibit the inactivated state of the channel, ST-2262 is equipotent in a protocol that favors the resting state of the channel, a protocol that favors the inactivated state, and a high frequency protocol. In a non-human primate study, animals treated with ST-2262 exhibited reduced sensitivity to noxious heat. These findings establish the extracellular vestibule of the sodium channel as a viable receptor site for the design of selective ligands targeting Na V 1.7.

The preparation of substituted azetidines and larger ring, nitrogen-containing saturated heterocycles is enabled through efficient and selective intermolecular sp 3 -C-H amination of alkyl bromide derivatives. A range of substrates are demonstrated to undergo C-H amination and subsequent sulfamate alkylation in good to excellent yield. N -Phenoxysulfonyl-protected products can be unmasked under neutral or mild basic conditions to yield the corresponding cyclic secondary amines. The preparative convenience of this protocol is demonstrated through gram-scale and telescoped multistep procedures. Application of this technology is highlighted in a nine-step total synthesis of an unusual azetidine-containing natural product, penaresidin B.

Voltage-gated sodium ion channels (Na V s) are integral to both neuronal and muscular signaling and are a primary target for a number of proteinaceous and small molecule toxins. Included among these neurotoxins is veratridine (VTD), a C-nor-D homosteroidal alkaloid from the seeds of members of the Veratrum genus. VTD binds to Na V within the pore region, causing a hyperpolarizing shift in the activation threshold in addition to reducing peak current. We have characterized the activity of VTD against heterologously expressed rat Na V 1.4 and have demonstrated that VTD acts on the channel as either an agonist or antagonist depending on the nature of the electrophysiological stimulation protocol. Structure-activity studies with VTD and VTD derivatives against Na V mutants show that the functional duality of VTD can be decoupled. These findings suggest that the dichotomous activity of VTD may derive from two distinct, use-dependent binding orientations of the toxin.

Introduction: The medical literature contains five cases of exanthema with sebaceous tropism induced by consumption of kava-kava extract filed under the name of sebotropic drug reaction. Herein we report a new case following consumption of bee pollen., Patients and Methods: A 37-year-old man consulted for erythemato-papular and fixed plaques of the face, upper trunk and shoulders present for 3 days. Standard blood tests were normal except for neutrophil leukocytosis at 9.8 G/l and eosinophilia at 1.4 G/l. Cutaneous biopsy of a facial plaque revealed folliculocentric lesions with necrosis of sebocytes in the sebaceous gland, associated with an eosinophil-rich infiltrate. The patient had begun consuming bee-pollen granules 3 weeks before the onset of symptoms. The rash regressed within 3 weeks of cessation of pollen consumption. Patch tests (ICDRG battery, propolis 1% Vaseline dilution and bee pollen provided by the patient, both pure and in a 30% dilution in Vaseline) were negative at 48 and 72h., Discussion: The clinical-pathological correlation was consistent with a diagnosis of sebotropic drug reaction induced by the consumption of bee pollen. The diagnosis was based on papular exanthema of the seborrheic zones occurring 2 to 3 weeks after initial intake of the offending substance, with histological evidence of inflammatory necrosis of the sebaceous glands., Conclusion: We report what is to our knowledge the first case of sebotropic drug reaction following ingestion of bee pollen., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Background: Infarct-artery (IRA) microvascular obstruction (MVO) is associated with diastolic dysfunction (DD) in STEMI patients. However, association between nonIRA MVO and DD in STEMI patients remains unknown. We hypothesized that revascularized STEMI patients with IRA and nonIRA MVO (IRA + nonIRA+), compared to those without nonIRA MVO (IRA + nonIRA-), have worse DD at presentation and long-term follow-up., Methods: 87 IRA-revascularized STEMI patients had cardiac magnetic resonance imaging (MRI) [to evaluate MVO] and TTE (to evaluate diastolic function) within 1 week of presentation. Diastolic function was re-assessed by TTE at 3.97 ± 3.24 years. Baseline and follow-up DD prevalence and grade were studied in IRA + nonIRA + vs. IRA + nonIRA- MVO patients., Results: 54 (62%) patients were IRA + nonIRA+ and 33 (38%) IRA + nonIRA-at baseline. IRA + nonIRA + patients had higher DD frequency at baseline (40.7 vs. 6.1%, p = 0.006) and follow-up (50.0 vs. 13.0%, p = 0.05). Only IRA + nonIRA + patients had increase in mitral medial E/e' (20.0%, p = 0.043) and trend towards increase in mitral E/A (31.1%, p = 0.063) at follow-up. IRA + nonIRA + patients had greater left atrial volume index increase (23.7%, p = 0.032 vs. 15.5%, p = 0.029) and smaller prolongation in deceleration time (15.4%, p = 0.018 vs. 18.7%, p = 0.044) at follow-up compared to IRA + nonIRA-. Grade 1 DD increased (60.9-73.9%) and combined grades 2/3 decreased (30.4-13.0%) at follow-up in IRA + nonIRA-patients. In contrast, grade 1 DD decreased (77.8-61.1%) and combined grades 2/3 increased (8.3-22.2%) at follow-up in IRA + nonIRA + patients., Conclusion: Concurrent IRA and nonIRA MVO in revascularized STEMI patients is associated with higher DD prevalence and worse DD grade on long-term follow-up., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Purpose: The aim of this study was to analyze the effect of epoch length on intensity classification during continuous and intermittent activities., Methods: Ten active students exercised under controlled conditions on a treadmill for four 5-min bouts by combining two effort intensities (running and walking) and two physical activity (PA) patterns (continuous or intermittent). The testing session was designed to generate a known level of moderate to vigorous PA (MVPA) for each condition. These PA levels were used as criterion measures to compare with the accelerometer measures. Data obtained from the accelerometer were reintegrated into 1-sec, 10-sec, 30-sec and 60-sec epochs. Equivalence testing was used to examine measurement agreements between MVPA values obtained with the different epochs and the reference values. Mean absolute percent errors (MAPE) were also calculated to provide an indicator of overall measurement error., Results: During the intermittent conditions, only the value obtained with the 1-sec epoch was significantly equivalent to the reference value. With longer epochs the difference increased for both intermittent conditions but in an opposite way: with longer epochs, MVPA decreased during walking but increased during running. Regarding the measurement accuracy, the pattern of variations according to the epoch length selected during the intermittent conditions was identical between walking and running: MAPE increased with the increase in epoch length. MAPE remained low only for the 1-sec epoch (7.6% and 2.7% for walking and running, respectively), increased at 31.3% and 34% for the 10-sec epoch and until near 100% with the 30- and 60-sec epoch lengths., Conclusion: This study highlighted the misclassification of exercise intensity based on accelerometer measurement and described for the first time the extent and the direction of this misclassification. Moreover, we can confirm that the shorter epochs are more accurate to measure the real exercise intensity during intermittent PA whatever the intensity., Competing Interests: The authors have declared that no competing interests exist.

Voltage-gated sodium ion channel subtype 1.7 (Na V 1.7) is a high interest target for the discovery of non-opioid analgesics. Compelling evidence from human genetic data, particularly the finding that persons lacking functional Na V 1.7 are insensitive to pain, has spurred considerable effort to develop selective inhibitors of this Na + ion channel target as analgesic medicines. Recent clinical setbacks and disappointing performance of preclinical compounds in animal pain models, however, have led to skepticism around the potential of selective Na V 1.7 inhibitors as human therapeutics. In this Perspective, we discuss the attributes and limitations of recently disclosed investigational drugs targeting Na V 1.7 and review evidence that, by better understanding the requirements for selectivity and target engagement, the opportunity to deliver effective analgesic medicines targeting Na V 1.7 endures.

Dinoflagelates and cyanobacteria produce saxitoxin (STX), a lethal bis-guanidinium neurotoxin causing paralytic shellfish poisoning. A number of metazoans have soluble STX-binding proteins that may prevent STX intoxication. However, their STX molecular recognition mechanisms remain unknown. Here, we present structures of saxiphilin (Sxph), a bullfrog high-affinity STX-binding protein, alone and bound to STX. The structures reveal a novel high-affinity STX-binding site built from a "proto-pocket" on a transferrin scaffold that also bears thyroglobulin domain protease inhibitor repeats. Comparison of Sxph and voltage-gated sodium channel STX-binding sites reveals a convergent toxin recognition strategy comprising a largely rigid binding site where acidic side chains and a cation-π interaction engage STX. These studies reveal molecular rules for STX recognition, outline how a toxin-binding site can be built on a naïve scaffold, and open a path to developing protein sensors for environmental STX monitoring and new biologics for STX intoxication mitigation.

The bis-guanidinium toxins are a collection of natural products that display nanomolar potency against select isoforms of eukaryotic voltage-gated Na + ion channels. We describe a synthetic strategy that enables access to four of these poisons, namely 11-saxitoxinethanoic acid, C13-acetoxy saxitoxin, decarbamoyl saxitoxin, and saxitoxin. Highlights of this work include an unusual Mislow-Evans rearrangement and a late-stage Stille ketene acetal coupling. The IC 50 value of 11-saxitoxinethanoic acid was measured against rat Na V 1.4, and found to be 17.0 nm, similar to those of the sulfated toxins gonyautoxin II and III., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: The diagnostic yield of combined cardiopulmonary exercise testing (CPET) and myocardial perfusion imaging (MPI) in patients referred for stress testing has received limited study., Methods: We evaluated consecutive patients who underwent combined CPET-MPI at a single tertiary referral center between 2011 and 2015. An abnormal CPET was defined as any of the following: reduced oxygen consumption, cardiac output impairment, or pulmonary impairment. Normal MPI was defined as the absence of resting or stress perfusion defect. The primary study outcome was change in clinical decision-making after CPET-MPI including management of pulmonary disease, management of deconditioning, heart failure management, and referral for cardiac catheterization. Outcomes of patients with normal and abnormal MPI were presented based on the specific CPET abnormality., Results: 415 patients were included in the study. Of the 269 patients that had normal MPI, 206 (77%) had abnormal CPET. Patients with abnormal CPET and normal MPI, compared with patients that had normal CPET and normal MPI, were more frequently diagnosed with pulmonary disease (11.7% vs 3.2%, P = .04) and deconditioning (33.5% vs 17.4%, P = .01). Of the 146 patients that had abnormal MPI, 128 (88%) had abnormal CPET. Patients with abnormal CPET and abnormal MPI, compared with patients that had normal CPET and abnormal MPI, did not statistically differ with regard to the study outcome., Conclusion: An abnormal CPET, if the MPI was normal, prompted further evaluation and led to management of pulmonary disease and deconditioning.

We have recently disclosed [(dtbpy) 2 RuCl 2 ] as an effective precatalyst for chemoselective C-H hydroxylation of C(sp 3 )-H bonds and have noted a marked disparity in reaction performance between 4,4'-di- tert-butyl-2,2'-bipyridine (dtbpy)- and 2,2'-bipyridine (bpy)-derived complexes. A desire to understand the origin of this difference and to further advance this catalytic method has motivated the comprehensive mechanistic investigation described herein. Details of this reaction have been unveiled through evaluation of ligand structure-activity relationships, electrochemical and kinetic studies, and pressurized sample infusion high-resolution mass spectrometry (PSI-MS). Salient findings from this investigation include the identification of more than one active oxidant and three disparate mechanisms for catalyst decomposition/arrest. Catalyst efficiency, as measured by turnover number, has a strong inverse correlation with the rate and extent of ligand dissociation, which is dependent on the identity of bipyridyl 4,4'-substituent groups. Dissociated bipyridyl ligand is oxidized to mono- and bis- N-oxide species under the reaction conditions, the former of which is found to act as a potent catalyst poison, yielding a catalytically inactive tris-ligated [Ru(dtbpy) 2 (dtbpy N-oxide)] 2+ complex. Insights gained through this work highlight the power of PSI-MS for studies of complex reaction processes and are guiding ongoing efforts to develop high-performance, next-generation catalyst systems for C-H hydroxylation.

Background: Coronary microvascular obstruction (MVO) in infarct-related artery (IRA) territory has been associated with worse cardiovascular outcomes in patients presenting with ST-segment elevation myocardial infarction. However, the prognostic value of non-IRA MVO in this patient population remains unknown., Methods and Results: One hundred ninety nine patients presenting to our institution with STEMI were enrolled. All patients underwent primary percutaneous coronary intervention per institutional STEMI protocol followed by a cardiac MRI within 1 week of presentation and the IRA and non-IRA MVO segments were determined. All cause death, recurrent myocardial infarction, hospitalization for heart failure, and ventricular tachycardia were counted as major adverse cardiovascular events (MACE). Patients with non-IRA MVO had lower composite MACE free survival at 6 months (HR 2.15, 95% CI, 1.06-4.35; p = 0.029) compared to those without non-IRA MVO. In a sub-analysis of patients with multi vessel disease (MVD), patients with non-IRA MVO also had lower composite MACE-free survival at 6 months as compared to those without non-IRA MVO (HR 2.47, 95% CI, 1.02-5.97; p = 0.037). Non-IRA MVO continued to be predictive of MACE in a cox proportional hazards model adjusting for additional prognostic factors using inverse probability weighting (p = 0.007). Non-IRA MVO was more prevalent in patients with LAD culprit vessel STEMI rather than those with RCA or Circumflex culprit vessels (p < 0.001)., Conclusions: Patients presenting with STEMI and non-IRA MVO have significantly lower MACE free survival at 6 months as compared to those without non-IRA MVO., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The remarkable degree of synthetic selectivity found in Nature is exemplified by the biosynthesis of paralytic shellfish toxins such as saxitoxin. The polycyclic core shared by saxitoxin and its relatives is assembled and subsequently elaborated through the installation of hydroxyl groups with exquisite precision that is not possible to replicate with traditional synthetic methods. Here, we report the identification of the enzymes that carry out a subset of C-H functionalizations involved in paralytic shellfish toxin biosynthesis. We have shown that three Rieske oxygenases mediate hydroxylation reactions with perfect site- and stereoselectivity. Specifically, the Rieske oxygenase SxtT is responsible for selective hydroxylation of a tricyclic precursor to the famous natural product saxitoxin, and a second Rieske oxygenase, GxtA, selectively hydroxylates saxitoxin to access the oxidation pattern present in gonyautoxin natural products. Unexpectedly, a third Rieske oxygenase, SxtH, does not hydroxylate tricyclic intermediates, but rather a linear substrate prior to tricycle formation, rewriting the biosynthetic route to paralytic shellfish toxins. Characterization of SxtT, SxtH, and GxtA is the first demonstration of enzymes carrying out C-H hydroxylation reactions in paralytic shellfish toxin biosynthesis. Additionally, the reactions of these oxygenases with a suite of saxitoxin-related molecules are reported, highlighting the substrate promiscuity of these catalysts and the potential for their application in the synthesis of natural and unnatural saxitoxin congeners.

A strategy enabled by C-H and alkene amination technologies for synthesizing the aminocyclitol natural product, pactamycin, is disclosed. This work features two disparate approaches for assembling the five-membered ring core of the target, the first of which utilizes acyl anion catalysis and a second involving β-ketoester aerobic hydroxylation. Installation of the C3-N bond, one of three contiguous nitrogen centers, is made possible through Rh-catalyzed allylic C-H amination of a sulfamate ester. Subsequent efforts are presented to introduce the C1,C2 cis-diamino moiety en route to pactamycin, including carbamate-mediated alkene aziridination. In the course of these studies, assembly of the core of C2- epi-pactamycate, which bears the carbon skeleton and all of the requisite nitrogen and oxygen functional groups found in the natural product, has been achieved.

Aims: Bedaquiline is an important novel drug for treatment of multidrug-resistant tuberculosis, but no paediatric formulation is yet available. This work aimed to explore the possibility of using the existing tablet formulation in children by evaluating the relative bioavailability, short-term safety, acceptability and palatability of suspended bedaquiline tablets compared to whole tablets., Methods: A randomized, open-label, two-period cross-over study was conducted in 24 healthy adult volunteers. Rich pharmacokinetic sampling over 48 h was conducted at two occasions 14 days apart in each participant after administration of 400 mg bedaquiline (whole or suspended in water). The pharmacokinetic data were analysed with nonlinear mixed-effects modelling. A questionnaire was used to assess palatability and acceptability., Results: There was no statistically significant difference in the bioavailability of the suspended bedaquiline tables compared to whole. The nonparametric 95% confidence interval of the relative bioavailability of suspended bedaquiline tablets was 94-108% of that of whole bedaquiline tablets; hence, the predefined bioequivalence criteria were fulfilled. There were no Grade 3 or 4 or serious treatment emergent adverse events recorded in the study and no apparent differences between whole tablets and suspension regarding taste, texture or smell., Conclusions: The bioavailability of bedaquiline tablets suspended in water was the same as for tablets swallowed whole and the suspension was well tolerated. This suggests that the currently available bedaquiline formulation could be used to treat multidrug-resistant tuberculosis in children, to bridge the gap between when paediatric dosing regimens have been established and when a paediatric dispersible formulation is routinely available., (© 2018 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

CLC proteins are a ubiquitously expressed family of chloride-selective ion channels and transporters. A dearth of pharmacological tools for modulating CLC gating and ion conduction limits investigations aimed at understanding CLC structure/function and physiology. Herein, we describe the design, synthesis, and evaluation of a collection of N -arylated benzimidazole derivatives (BIMs), one of which (BIM1) shows unparalleled (>20-fold) selectivity for CLC-Ka over CLC-Kb, the two most closely related human CLC homologs. Computational docking to a CLC-Ka homology model has identified a BIM1 binding site on the extracellular face of the protein near the chloride permeation pathway in a region previously identified as a binding site for other less selective inhibitors. Results from site-directed mutagenesis experiments are consistent with predictions of this docking model. The residue at position 68 is 1 of only ∼20 extracellular residues that differ between CLC-Ka and CLC-Kb. Mutation of this residue in CLC-Ka and CLC-Kb (N68D and D68N, respectively) reverses the preference of BIM1 for CLC-Ka over CLC-Kb, thus showing the critical role of residue 68 in establishing BIM1 selectivity. Molecular docking studies together with results from structure-activity relationship studies with 19 BIM derivatives give insight into the increased selectivity of BIM1 compared with other inhibitors and identify strategies for further developing this class of compounds., Competing Interests: The authors declare no conflict of interest.

A general and operationally convenient method for intermolecular amination of C(sp 3 )-H bonds is described. This technology allows for efficient functionalization of complex molecules, including numerous pharmaceutical targets. The combination of pivalonitrile as a solvent, Al 2 O 3 as an additive, and phenyl sulfamate as a nitrogen source affords differential reaction performance and substrate scope. Mechanistic data strongly implicate a pathway for catalyst decomposition that initiates with solvent oxidation, thus providing rationale for the marked influence of pivalonitrile on this reaction process., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The desire for maximally efficient transformations in complex molecule synthesis has contributed to a surge of interest in C-H functionalization methods development in recent years. In contrast to the steady stream of methodological reports, however, there are noticeably fewer studies comparing the efficacies of different C-H functionalization protocols on a single structurally intricate substrate. Recognizing the importance of heteroatom incorporation in complex molecule synthesis, this report discloses a comparative examination of diverse strategies for C-O, C-N, and C-X bond formation through late-stage C-H oxidation of the tricyclic cyanthiwigin natural product core. Methods for allylic C-H acetoxylation, tertiary C-H hydroxylation, tertiary C-H amination, tertiary C-H azidation, and secondary C-H halogenation are explored. These efforts highlight the robustness and selectivities of many well-established protocols for C-H oxidation when applied to a complex molecular framework, and the findings are relevant to chemists aiming to employ such strategies in the context of chemical synthesis.

A method for converting sp 3 C-H to C-Br bonds using an N -methyl sulfamate directing group is described. The reaction employs Rh 2 (oct) 4 and a mixture of NaBr and NaOCl and is performed in aqueous solution open to air. For all sulfamates examined, oxidation occurs with high selectivity at the γ-carbon, affording a uniquely predictable method for C-H bond halogenation. Results from a series of mechanistic experiments suggest that substrate oxidation likely proceeds by a radical chain process. Initial formation of an N -halogenated sulfamate followed by Rh-mediated homolysis generates an N-centered radical, which serves as the active oxidant.

The homodinuclear ruthenium(II) complex [{Ru(l-N 4 Me 2 )} 2 (μ-tape)](PF 6 ) 4 {[1](PF 6 ) 4 } (l-N 4 Me 2 =N,N'-dimethyl-2,11-diaza[3.3](2,6)-pyridinophane, tape=1,6,7,12-tetraazaperylene) can store one or two electrons in the energetically low-lying π* orbital of the bridging ligand tape. The corresponding singly and doubly reduced complexes [{Ru(l-N 4 Me 2 )} 2 (μ-tape .- )](PF 6 ) 3 {[2](PF 6 ) 3 } and [{Ru(l-N 4 Me 2 )} 2 (μ-tape 2- )](PF 6 ) 2 {[3](PF 6 ) 2 }, respectively, were electrochemically generated, successfully isolated and fully characterized by single-crystal X-ray crystallography, spectroscopic methods and magnetic susceptibility measurements. The singly reduced complex [2](PF 6 ) 3 contains the π-radical tape .- and the doubly reduced [3](PF 6 ) 2 the diamagnetic dianion tape 2- as bridging ligand, respectively. Nucleophilic aromatic substitution at the bridging tape in [1] 4+ by two sulfite units gave the complex [{Ru(l-N 4 Me 2 )} 2 {μ-tape-(SO 3 ) 2 }] 2+ ([4] 2+ ). Complex dication [4] 2+ was exploited as a redox mediator between an anaerobic homogenous reaction solution of an enzyme system (sulfite/sulfite oxidase) and the electrode via participation of the low-energy π*-orbital of the disulfonato-substituted bridging ligand tape-(SO 3 ) 2 2- (E red1 =-0.1 V versus Ag/AgCl/1 m KCl in water)., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

G 0 W 0 calculations for predicting vertical ionization potentials (IPs) and electron affinities of molecules and clusters are known to show a significant dependence on the density functional theory (DFT) starting point. A number of nonempirical procedures to find an optimal starting point have been proposed, typically based on tuning the amount of HF exchange in the underlying hybrid functional specifically for the system at hand. For the case of π-conjugated molecular chains, these approaches lead to a significantly different amount of HF exchange for different oligomer sizes. In this study, we analyze if and how strongly this size dependence affects the ability of nonempirical tuning approaches to predict accurate IPs for π-conjugated molecular chains of increasing chain length. To this end, we employ three different nonempirical tuning procedures for the G 0 W 0 starting point to calculate the IP of polyene oligomers up to 22 repeat units and compare the results to highly accurate coupled-cluster calculations. We find that, despite its size dependence, using an IP-tuned hybrid functional as a starting point for G 0 W 0 yields excellent agreement with the reference data for all chain lengths.

We recently reported that carboxylic acids can be oxidized to lactone products by potassium persulfate and catalytic copper acetate. Here, we unravel the mechanism for this C-H functionalization reaction using desorption electrospray ionization, online electrospray ionization, and tandem mass spectrometry. Our findings suggest that electron transfer from a transient benzylic radical intermediate reduces Cu(ii) to Cu(i), which is then re-oxidized to Cu(ii) in the catalytic cycle. The resulting benzylic carbocation is trapped by the pendant carboxylate group to give the lactone product. Formation of the putative benzylic carbocation is supported by Hammett analysis. The proposed mechanism for this copper-catalyzed oxidative cyclization process differs from earlier reports of analogous reactions, which posit a substrate carboxylate radical as the reactive oxidant.

AZD-5847 is a new oxazolidinone derivative under development for the treatment of tuberculosis (TB). Here we describe the population pharmacokinetics (PK) of AZD-5847 in patients with tuberculosis based on a recently completed phase II study. The study included 60 patients with drug-susceptible TB. Patients were randomized to four dosages (500 mg once daily, 1,200 mg once daily, 500 mg twice daily, and 800 mg twice daily). Patients were intensively sampled on days 1 and 14. AZD-5847 pharmacokinetics were best described with a two-compartment model with lag time ( T lag ) for absorption. AZD-5847 bioavailability was nonlinear and plateaued at 800 mg. We performed deterministic simulation to compare the PK/pharmacodynamics (PD) of AZD-5847, linezolid, and sutezolid. AZD-5847 PK/PD in terms of both area under the concentration-time curve for the free, unbound fraction ( f AUC)/MIC and time the free concentration was above the MIC ( f T>MIC) were less favorable than those for linezolid and sutezolid. This could help explain the poor bactericidal activity of AZD-5847 in the recent phase II study., (Copyright © 2017 American Society for Microbiology.)

Exposure of the toxin-producing dinoflagellate Alexandrium catenella (A. catenella) was previously demonstrated to cause apoptosis of hemocytes in the oyster species Crassostrea gigas. In this work, a coumarin-labeled saxitoxin appeared to spread throughout the cytoplasm of the hemocytes. PSTs, including saxitoxin, were also shown to be directly responsible for inducing apoptosis in hemocytes, a process dependent on caspase activation and independent of reactive oxygen species (ROS) production. A series of in vitro labelling and microscopy experiments revealed that STX and analogs there of induced nuclear condensation, phosphatidylserine exposure, membrane permeability, and DNA fragmentation of hemocytes. Unlike in vertebrates, gonyautoxin-5 (GTX5), which is present in high concentrations in A. catenella, was found to be more toxic than saxitoxin (STX) to oyster immune cells. Altogether, results show that PSTs produced by toxic dinoflagellates enter the cytoplasm and induce apoptosis of oyster immune cells through a caspase-dependent pathway. Because of the central role of hemocytes in mollusc immune defense, PST-induced death of hemocytes could negatively affect resistance of bivalve molluscs to microbial infection., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The identification, optimization, and evaluation of a new catalytic protocol for sp 3 C-H hydroxylation is described. Reactions are performed in aqueous acid using a bis(bipyridine)Ru catalyst to enable oxidation of substrates possessing basic amine functional groups. Tertiary and benzylic C-H hydroxylation is strongly favored over N-oxidation for numerous amine derivatives. With terpene-derived substrates, similar trends in reactivity toward tertiary and benzylic C-H bonds are observed. Hydroxylation of chiral tertiary centers is enantiospecific in spite of the ionizing strength of the reaction medium. Preliminary kinetics experiments show a marked difference in reactivity between isomeric cis- and trans-Ru catalysts suggesting that the catalyst is configurationally stable under the reaction conditions.

A method for converting C-H to C-O bonds through oxidative cyclization of carboxylic acids to generate lactone products is described. The reaction employs catalytic amounts of Cu(OAc) 2 and potassium persulfate as the terminal oxidant and is performed open to air in an aqueous acetic acid solvent system. Preliminary mechanistic studies suggest that substrate oxidation likely proceeds by sulfate radical anion and that the Cu catalyst has no influence on the product-determining step. These conclusions differ from related investigations that propose the intermediacy of a carboxylate radical.

The steroidal neurotoxin (-)-batrachotoxin functions as a potent agonist of voltage-gated sodium ion channels (Na V s). Here we report concise asymmetric syntheses of the natural (-) and non-natural (+) antipodes of batrachotoxin, as well both enantiomers of a C-20 benzoate-modified derivative. Electrophysiological characterization of these molecules against Na V subtypes establishes the non-natural toxin enantiomer as a reversible antagonist of channel function, markedly different in activity from (-)-batrachotoxin. Protein mutagenesis experiments implicate a shared binding side for the enantiomers in the inner pore cavity of Na V These findings motivate and enable subsequent studies aimed at revealing how small molecules that target the channel inner pore modulate Na V dynamics., (Copyright © 2016, American Association for the Advancement of Science.)

AZD5847 is an oxazolidinone antibiotic with in vitro activity against Mycobacterium tuberculosis The objective of this study was to evaluate the antimycobacterial activity, safety, and pharmacokinetics of AZD5847 in patients with pulmonary tuberculosis. Groups of 15 treatment-naive, sputum smear-positive adults with pulmonary tuberculosis were randomly assigned to receive AZD5847 at one of four doses (500 mg once daily, 500 mg twice daily, 1,200 mg once daily, and 800 mg twice daily) or daily standard chemotherapy. The primary efficacy endpoint was the mean daily rate of change in the log 10 number of CFU of M. tuberculosis per milliliter of sputum, expressed as the change in log 10 number of CFU per milliliter of sputum per day. The mean 14-day activity of the combination of isoniazid, rifampin, ethambutol, and pyrazinamide (-0.163 log 10 CFU/ml sputum/day; 95% confidence interval [CI], -0.193, -0.133 log 10 CFU/ml sputum/day) was consistent with that found in previous studies. AZD5847 at 500 mg twice daily significantly decreased the number of CFU on solid medium (-0.039; 95% CI, -0.069, -0.009; P = 0.0048). No bactericidal activity was detected at doses of AZD5847 of 500 mg once daily (mean early bactericidal activity [EBA], 0.02 [95% CI, -0.01, 0.05]), 1,200 mg once daily (mean EBA, 0.02 [95% CI, -0.01, 0.05]), and 800 mg twice daily (mean EBA, 0.02 [95% CI, -0.01, 0.05]). AZD5847 at doses of both 500 mg and 800 mg twice daily also showed an increase in the time to a positive culture in MGIT liquid culture medium. Two serious adverse events (grade 4 thrombocytopenia and grade 4 hyperbilirubinemia) occurred in patients receiving AZD5847 at higher doses. AZD5847 dosed twice daily kills tubercle bacilli in the sputum of patients with pulmonary tuberculosis and has modest early bactericidal activity. (This study has been registered at ClinicalTrials.gov under registration no. NCT01516203.)., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

A novel family of small molecule inhibitors of voltage-gated sodium channels (Na V s) based on the structure of batrachotoxin (BTX), a well-known channel agonist, is described. Protein mutagenesis and electrophysiology experiments reveal the binding site as the inner pore region of the channel, analogous to BTX, alkaloid toxins, and local anesthetics. Homology modeling of the eukaryotic channel based on recent crystallographic analyses of bacterial Na V s suggests a mechanism of action for ion conduction block.

An in situ generated catalyst system based on Mn(CF3SO3)2, picolinic acid, and peracetic acid converts an extensive scope of olefins to their epoxides at 0 °C in <5 min, with remarkable oxidant efficiency and no evidence of radical behavior. Competition experiments indicate an electrophilic active oxidant, proposed to be a high-valent Mn = O species. Ligand exploration suggests a general ligand sphere motif contributes to effective oxidation. The method is underscored by its simplicity and use of inexpensive reagents to quickly access high value-added products.

Improper function of voltage-gated sodium channels (NaVs), obligatory membrane proteins for bioelectrical signaling, has been linked to a number of human pathologies. Small-molecule agents that target NaVs hold considerable promise for treatment of chronic disease. Absent a comprehensive understanding of channel structure, the challenge of designing selective agents to modulate the activity of NaV subtypes is formidable. We have endeavored to gain insight into the 3D architecture of the outer vestibule of NaV through a systematic structure-activity relationship (SAR) study involving the bis-guanidinium toxin saxitoxin (STX), modified saxitoxins, and protein mutagenesis. Mutant cycle analysis has led to the identification of an acetylated variant of STX with unprecedented, low-nanomolar affinity for human NaV1.7 (hNaV1.7), a channel subtype that has been implicated in pain perception. A revised toxin-receptor binding model is presented, which is consistent with the large body of SAR data that we have obtained. This new model is expected to facilitate subsequent efforts to design isoform-selective NaV inhibitors.

The paralytic shellfish poisons are a collection of guanidine-containing natural products that are biosynthesized by prokaryote and eukaryote marine organisms. These compounds bind and inhibit isoforms of the mammalian voltage-gated Na(+) ion channel at concentrations ranging from 10(-11) to 10(-5) M. Here, we describe the de novo synthesis of three paralytic shellfish poisons, gonyautoxin 2, gonyautoxin 3, and 11,11-dihydroxysaxitoxin. Key steps include a diastereoselective Pictet-Spengler reaction and an intramolecular amination of an N-guanidyl pyrrole by a sulfonyl guanidine. The IC50's of GTX 2, GTX 3, and 11,11-dhSTX have been measured against rat NaV1.4, and are found to be 22 nM, 15 nM, and 2.2 μM, respectively.

We dissect the sources of error leading to inaccuracies in the description of the geometry and optical excitation energies of π-conjugated polymers. While the ground-state bond length alternation is shown to be badly reproduced by standard functionals, the recently adapted functionals PBEh* and ωPBE* as well as the double hybrid functional XYGJ-OS manage to replicate results obtained at the CCSD(T) level. By analysis of the bond length alternation in the excited state, a sensitive dependence of the exciton localization on the long-range behavior of the functional and the amount of Hartree-Fock exchange present is shown. Introducing thermal disorder through molecular dynamics simulations allows the consideration of a range of thermally accessible configurations of each oligomer, including trans to cis rotations, which break the conjugation of the backbone. Thermal disorder has a considerable effect when combined with functionals that overestimate the delocalization of the excitation, such as B3LYP. For functionals with a larger amount of exact exchange such as our PBEh* and ωPBE*, however, the effect is small, as excitations are often localized enough to fit between twists in the chain.

Purpose: To report on the incidence of vertebral fractures in patients treated with Intensity Modulated Radiotherapy (IMRT) for locally advanced non-small cell lung carcinoma (NSCLC) and to analyse the association with clinical and dosimetric parameters., Patients and Methods: Between 2007 and 2012, 524 patients treated with ⩾51 Gy were retrospectively analysed for the incidence of vertebral fractures (VF). Clinical parameters were assessed. In addition, a case control study in 50 patients was performed to study the association between the radiotherapy dose and fractured vertebrae., Results: Three hundred and thirty-six patients were eligible for analyses. Twenty-eight patients (8%) were observed with VF at a median follow up of 12 months. Age was significantly higher in the group with VF (p<0.01). After balancing age, the mean vertebrae dose was most significantly associated with fractures of the vertebrae (p<0.01)., Conclusion: VF was observed in 8% of the patients with locally advanced NSCLC. RT dose was associated with the occurrence of thoracic vertebral fractures., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Dirhodium-catalyzed C-H amination is hypothesized to proceed via Rh2-nitrene intermediates in either the Rh2(II,II) or Rh2(II,III) redox state. Herein, we report joint theoretical and experimental studies of the ground electronic state (GES), redox potentials, and C-H amination of [Rh2(II,III)(O2CCH3)4(L)n](+) (1&#95;L) (L = none, Cl(-), and H2O), [Rh2(esp)2](+) (2), and Rh2(espn)2Cl (3) (esp = α,α,α',α'-tetramethyl-1,3-benzenedipropanoate and espn = α,α,α',α'-tetramethyl-1,3-benzenedipropanamidate). CASSCF calculations on 1&#95;L yield a wave function with two closely weighted configurations, (δ*)(2)(π1*)(2)(π2*)(1) and (δ*)(2)(π1*)(1)(π2*)(2), consistent with reported EPR g values [Chem. Phys. Lett. 1986, 130, 20-23]. In contrast, EPR spectra of 2 show g values consistent with the DFT-computed (π*)(4)(δ*)(1) GES. EPR spectra and Cl K-edge XAS for 3 are consistent with a (π*)(4)(δ*)(1) GES, as supported by DFT. Nitrene intermediates 2N&#95;L and 3N&#95;L are also examined by DFT (the nitrene is an NSO3R species). DFT calculations suggest a doublet GES for 2N&#95;L and a quartet GES for 3N&#95;L. CASSCF calculations describe the GES of 2N as Rh2(II,II) with a coordinated nitrene radical cation, (π*)(4)(δ*)(2)(π(nitrene,1))(1)(π(nitrene,2))(0). Conversely, the GES of 3N is Rh2(II,III) with a coordinated triplet nitrene, (π*)(4)(δ*)(1)(π(nitrene,1))(1)(π(nitrene,2))(1). Quartet transition states ((4)TSs) are found to react via a stepwise radical mechanism, whereas (2)TSs are found to react via a concerted mechanism that is lower in energy compared to (4)TSs for both 2N&#95;L and 3N&#95;L. The experimental (determined by intramolecular competition) and (2)TS-calculated kinetic isotopic effect (KIE) shows a KIE ∼ 3 for both 2N and 3N, which is consistent with a concerted mechanism.

A comparative study is disclosed that seeks to highlight the current limitations and challenges that exist in the field of atom-transfer C-H oxidations. State-of-the-art methods are benchmarked in order to showcase clear differences and similarities. A novel Mn-mediated method for C-H oxidation is disclosed that serves as a rapid and simple method for aliphatic C-H hydroxylation. Finally, two methods that allow for C-H oxidation in the presence of pyridine-containing substrates are studied, something that is rare in the field but of great interest to the chemical community.

Aim: This study investigated the stages of change in physical activity in relation to psychological variables: self-efficacy, physical self-concept and barriers to physical activity, as well as gender. Furthermore, cluster profiles were created based on psychological variables to be compared with stages of change groups., Methods: Data were obtained from a representative sample of adolescents (N.=1618, 14.46±1.28 years) from Aragon region (Spain). The different strata were selected according to the geographical region, environment, type of school, age and gender, Results: Males (75.5%) and very active adolescents (96.9% participant boys and 93.5% participants girls) were more prevalent in the action and maintenance groups. We found significant differences in psychosocial variables by stages of change and gender, showing higher scores in active groups for physical self-concept (effects of gender and stages of change: F(1, 1618)=313.82 P<0.001, η²=0.230) and self-efficacy (F(1, 1618)=324.34 P<0.001, η²=0.236), and lower scores in passive groups for intrapersonal (F(1, 1618)=179.73 P<0.001, η²=0.146) and extrapersonal barriers (F(1, 1618)=189.42 P<0.001, η²=0.153). Psychological cluster profiles created with these variables showed significant relationships with stages of change groups (χ²(1)=162,76, P<0.001; Pearson R=0.359 P<0.001)., Conclusion: The findings of the research suggest the importance of the study, showing strong determinants of PA, physical self-concept, self-efficacy and perceived barriers, in relation to the intention to change behaviour, not only stage of change model variables. Furthermore, the study can be relevant to designing more effective health promotion programmes in the adolescent population.

Objectives: SQ109, an asymmetrical diamine, is a novel anti-TB drug candidate. This first study in patients was done to determine safety, tolerability, pharmacokinetics and bacteriological effect of different doses of SQ109 alone and in combination with rifampicin when administered over 14 days., Patients and Methods: Smear-positive pulmonary TB patients were randomized into six groups of 15 to receive once-daily oral treatment with 75, 150 or 300 mg of SQ109, rifampicin (10 mg/kg body weight), rifampicin plus 150 mg of SQ109, or rifampicin plus 300 mg of SQ109 for 14 days. Patients were hospitalized for supervised treatment, regular clinical, biochemical and electrocardiographic safety assessments, pharmacokinetic profiling and daily overnight sputum collection., Results: SQ109 was safe and generally well tolerated. Mild to moderate dose-dependent gastrointestinal complaints were the most frequent adverse events. No relevant QT prolongation was noted. Maximum SQ109 plasma concentrations were lower than MICs. Exposure to SQ109 (AUC0-24) increased by drug accumulation upon repeated administration in the SQ109 monotherapy groups. Co-administration of SQ109 150 mg with rifampicin resulted in decreasing SQ109 exposures from day 1 to day 14. A higher (300 mg) dose of SQ109 largely outweighed the evolving inductive effect of rifampicin. The daily fall in log cfu/mL of sputum (95% CI) was 0.093 (0.126-0.059) with rifampicin, 0.133 (0.166-0.100) with rifampicin plus 150 mg of SQ109 and 0.089 (0.121-0.057) with rifampicin plus 300 mg of SQ109. Treatments with SQ109 alone showed no significant activity., Conclusions: SQ109 alone or with rifampicin was safe over 14 days. Upon co-administration with rifampicin, 300 mg of SQ109 yielded a higher exposure than the 150 mg dose. SQ109 did not appear to be active alone or to enhance the activity of rifampicin during the 14 days of treatment., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Rationale: Rifampin at a dose of 10 mg/kg was introduced in 1971 based on pharmacokinetic, toxicity, and cost considerations. Available data in mice and humans showed that an increase in dose may shorten the duration of tuberculosis treatment., Objectives: To evaluate the safety and tolerability, the pharmacokinetics, and the extended early bactericidal activity of increasing doses of rifampin., Methods: Patients with drug-susceptible tuberculosis were enrolled into a control group of eight patients receiving the standard dose of 10 mg/kg rifampin, followed by consecutive experimental groups with 15 patients each receiving rifampin 20, 25, 30, and 35 mg/kg, respectively, for 14 days. In all patients isoniazid, pyrazinamide, and ethambutol were added in standard doses for the second 7 days of treatment. Safety, pharmacokinetics of rifampin, and fall in bacterial load were assessed., Measurements and Main Results: Grade 1 and 2 adverse events were equally distributed between the five dose groups; there were five grade 3 events of which one was a possibly related hepatotoxicity. Areas under the time-concentration curves and peak serum concentrations of rifampin showed a more than proportional increase with dose. The daily fall in bacterial load over 14 days was 0.176, 0.168, 0.167, 0.265, and 0.261 log10 colony-forming units/ml sputum in the 10, 20, 25, 30, and 35 mg/kg groups, respectively., Conclusions: Two weeks of rifampin up to 35 mg/kg was safe and well tolerated. There was a nonlinear increase in exposure to rifampin without an apparent ceiling effect and a greater estimated fall in bacterial load in the higher dosing groups. Clinical trial registered with www.clinicaltrials.gov (NCT 01392911).