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Background: Globally, over 16 million children were exposed to HIV during pregnancy but remain HIV-free at birth and throughout childhood by 2022. Children born HIV-free (CBHF) have higher morbidity and mortality and poorer neurodevelopment in early life compared to children who are HIV-unexposed (CHU), but long-term outcomes remain uncertain. We characterised school-age growth, cognitive and physical function in CBHF and CHU previously enrolled in the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in rural Zimbabwe., Methods and Findings: The SHINE trial enrolled pregnant women between 2012 and 2015 across 2 rural Zimbabwean districts. Co-primary outcomes were height-for-age Z-score and haemoglobin at age 18 months (clinicaltrials.gov NCT01824940). Children were re-enrolled if they were aged 7 years, resident in Shurugwi district, and had known pregnancy HIV-exposure status. From 5,280 pregnant women originally enrolled, 376 CBHF and 2016 CHU reached the trial endpoint at 18 months in Shurugwi; of these, 264 CBHF and 990 CHU were evaluated at age 7 years using the School-Age Health, Activity, Resilience, Anthropometry and Neurocognitive (SAHARAN) toolbox. Cognitive function was evaluated using the Kaufman Assessment Battery for Children (KABC-II), with additional tools measuring executive function, literacy, numeracy, fine motor skills, and socioemotional function. Physical function was assessed using standing broad jump and handgrip for strength, and the shuttle-run test for cardiovascular fitness. Growth was assessed by anthropometry. Body composition was assessed by bioimpedance analysis and skinfold thicknesses. A caregiver questionnaire measured demographics, socioeconomic status, nurturing, child discipline, food, and water insecurity. We prespecified the primary comparisons and used generalised estimating equations with an exchangeable working correlation structure to account for clustering. Adjusted models used covariates from the trial (study arm, study nurse, exact child age, sex, calendar month measured, and ambient temperature). They also included covariates derived from directed acyclic graphs, with separate models adjusted for contemporary variables (socioeconomic status, household food insecurity, religion, social support, gender norms, caregiver depression, age, caregiver education, adversity score, and number of children's books) and early-life variables (length-for-age-Z-score) at 18 months, birthweight, maternal baseline depression, household diet, maternal schooling and haemoglobin, socioeconomic status, facility birth, and gender norms. We applied a Bonferroni correction for the 27 comparisons (0.05/27) with threshold of p < 0.00185 as significant. We found strong evidence that cognitive function was lower in CBHF compared to CHU across multiple domains. The KABC-II mental processing index was 45.2 (standard deviation (SD) 10.5) in CBHF and 48.3 (11.3) in CHU (mean difference 3.3 points [95% confidence interval (95% CI) 2.0, 4.5]; p < 0.001). The school achievement test score was 39.0 (SD 26.0) in CBHF and 45.7 (27.8) in CHU (mean difference 7.3 points [95% CI 3.6, 10.9]; p < 0.001); differences remained significant in adjusted analyses. Executive function was reduced but not significantly in adjusted analyses. We found no consistent evidence of differences in growth or physical function outcomes. The main limitation of our study was the restriction to one of two previous study districts, with possible survivor and selection bias., Conclusions: In this study, we found that CBHF had reductions in cognitive function compared to CHU at 7 years of age across multiple domains. Further research is needed to define the biological and psychosocial mechanisms underlying these differences to inform future interventions that help CBHF thrive across the life-course., Trial Registration: ClinicalTrials.gov The SHINE follow-up study was registered with the Pan-African Clinical Trials Registry (PACTR202201828512110). The original SHINE trial was registered at NCT https://clinicaltrials.gov/study/NCT01824940., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Piper et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Low birthweight (LBW) is when an infant is born too soon or too small, and it affects one in seven infants in low- and middle-income countries. LBW has a significant impact on short-term morbidity and mortality, and it impairs long-term health and human capital. Antenatal microbial and inflammatory exposure may contribute to LBW., Methods: Ovid-Medline, Embase and Cochrane databases were searched for English-language articles evaluating inflammatory, microbial or infective causes of LBW, small-for-gestational age, intra-uterine growth restriction or prematurity. Inclusion criteria were human studies including published data; conference abstracts and grey literature were excluded. A narrative synthesis of the literature was conducted., Results: Local infections may drive the underlying causes of LBW: for example, vaginitis and placental infection are associated with a greater risk of prematurity. Distal infection and inflammatory pathways are also associated with LBW, with an association between periodontitis and preterm delivery and environmental enteric dysfunction and reduced intra-uterine growth. Systemic maternal infections such as malaria and HIV are associated with LBW, even when infants are exposed to HIV but not infected. This latter association may be driven by chronic inflammation, co-infections and socio-economic confounders. Antimicrobial prophylaxis against other bacteria in pregnancy has shown minimal impact in most trials, though positive effects on birthweight have been found in some settings with a high infectious disease burden., Conclusion: Maternal inflammatory and infective processes underlie LBW, and provide treatable pathways for interventions. However, an improved understanding of the mechanisms and pathways underlying LBW is needed, given the impact of LBW on life-course.

Background: Neurodevelopment assessment tools for low-resource settings are urgently needed. However, most available tools were developed in high-income settings and may lack cross-cultural validity., Methods: We piloted and adapted two subtests within the planning domain of the Kaufman Assessment Battery for Children-2nd edition (KABC-II) for use in rural Zimbabwean children aged 7years. After initial assessments of face validity, we created 4 substitutions for the story completion subtest and 7 additions for the pattern reasoning subtest through a co-design process with fieldworkers and child development experts. To assess how successful the changes were, T-tests adjusting for unequal variances were used to compare scores between the original and adapted versions of the same subtest. ANOVA and pairwise analysis was performed to compare the performance of KABC-II subtests across domains. Intraclass correlation coefficient was calculated to explore the variability between domains., Results: Initial test scores on the planning domain were significantly lower than the other three domains of learning, sequential memory and simultaneous reasoning (P<0.001) in 50 children (mean age 7.6(SD 0.2) years). Modified subtests were administered to another 20 children (mean age 7.6(SD 0.2) years), who showed story completion scores that were 0.7 marks higher (95% CI 0.0, 1.4; P=0.05) and pattern reasoning scores 1.8 marks higher (95% CI 0.5, 3.2; P=0.01). Overall, the planning domain mean score increased from 8.1 (SD 2.9) to 10.6 (SD 3.4). The intra class correlation coefficient between all four KABC-II domains was initially 0.43 (95% CI 0.13, 0.64) and after modification was 0.69 (95% CI 0.37, 0.87), suggesting an increase in the construct validity., Conclusions: The KABC-II planning domain was successfully adapted to improve cross-cultural validity. Construct validity was enhanced, based on increased inter-correlations among scales. The process of co-design to modify tests for new settings may be beneficial for other commonly used neurodevelopmental tools., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Piper JD et al.)

HIV and severe wasting are associated with post-discharge mortality and hospital readmission among children with complicated severe acute malnutrition (SAM); however, the reasons remain unclear. We assessed body composition at hospital discharge, stratified by HIV and oedema status, in a cohort of children with complicated SAM in three hospitals in Zambia and Zimbabwe. We measured skinfold thicknesses and bioelectrical impedance analysis (BIA) to investigate whether fat and lean mass were independent predictors of time to death or readmission. Cox proportional hazards models were used to estimate the association between death/readmission and discharge body composition. Mixed effects models were fitted to compare longitudinal changes in body composition over 1 year. At discharge, 284 and 546 children had complete BIA and skinfold measurements, respectively. Low discharge lean and peripheral fat mass were independently associated with death/hospital readmission. Each unit Z -score increase in impedance index and triceps skinfolds was associated with 48 % (adjusted hazard ratio 0·52, 95 % CI (0·30, 0·90)) and 17 % (adjusted hazard ratio 0·83, 95 % CI (0·71, 0·96)) lower hazard of death/readmission, respectively. HIV-positive v . HIV-negative children had lower gains in sum of skinfolds (mean difference -1·49, 95 % CI (-2·01, -0·97)) and impedance index Z -scores (-0·13, 95 % CI (-0·24, -0·01)) over 52 weeks. Children with non-oedematous v . oedematous SAM had lower mean changes in the sum of skinfolds (-1·47, 95 % CI (-1·97, -0·97)) and impedance index Z -scores (-0·23, 95 % CI (-0·36, -0·09)). Risk stratification to identify children at risk for mortality or readmission, and interventions to increase lean and peripheral fat mass, should be considered in the post-discharge care of these children.

Background : There is a need for follow-up of early-life stunting intervention trials into childhood to determine their long-term impact. A holistic school-age assessment of health, growth, physical and cognitive function will help to comprehensively characterise the sustained effects of early-life interventions. Methods: The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in rural Zimbabwe assessed the effects of improved infant and young child feeding (IYCF) and/or improved water, sanitation and hygiene (WASH) on stunting and anaemia at 18 months. Among children enrolled to SHINE, 1,275 have been followed up at 7-8 years of age (1,000 children who have not been exposed to HIV, 268 exposed to HIV antenatally who remain HIV negative and 7 HIV positive children). Children were assessed using the School-Age Health, Activity, Resilience, Anthropometry and Neurocognitive (SAHARAN) toolbox, to measure their growth, body composition, cognitive and physical function. In parallel, a caregiver questionnaire assessed household demographics, socioeconomic status, adversity, nurturing, caregiver support, food and water insecurity. A monthly morbidity questionnaire is currently being administered by community health workers to evaluate school-age rates of infection and healthcare-seeking. The impact of the SHINE IYCF and WASH interventions, the early-life 'exposome', maternal HIV, and contemporary exposures on each school-age outcome will be assessed. We will also undertake an exploratory factor analysis to generate new, simpler metrics for assessment of cognition (COG-SAHARAN), growth (GROW-SAHARAN) and combined growth, cognitive and physical function (SUB-SAHARAN). The SUB-SAHARAN toolbox will be used to conduct annual assessments within the SHINE cohort from ages 8-12 years. Ethics and dissemination: Approval was obtained from Medical Research Council of Zimbabwe (08/02/21) and registered with Pan-African Clinical Trials Registry (PACTR202201828512110, 24/01/22). Primary caregivers provided written informed consent and children written assent. Findings will be disseminated through community sensitisation, peer-reviewed journals and stakeholders including the Zimbabwean Ministry of Health and Child Care., Competing Interests: No competing interests were disclosed., (Copyright: © 2023 Piper JD et al.)

Introduction: We developed the School-Age Health, Activity, Resilience, Anthropometry and Neurocognitive (SAHARAN) toolbox to address the shortage of school-age assessment tools that combine growth, physical and cognitive function. Here we present i) development, acceptability and feasibility of the SAHARAN toolbox; ii) characteristics of a pilot cohort; and iii) associations between the domains measured in the cohort., Methods: Growth was measured with anthropometry, knee-heel length and skinfold thicknesses. Bioimpedance analysis measured lean mass index and phase angle. Cognition was assessed using the mental processing index, derived from the Kaufman Assessment Battery for Children version 2, a fine motor finger-tapping task, and School Achievement Test (SAT). Physical function combined grip strength, broad jump and the 20m shuttle-run test to produce a total physical score. A caregiver questionnaire was performed in parallel., Results: The SAHARAN toolbox was feasible to implement in rural Zimbabwe, and highly acceptable to children and caregivers following some minor modifications. Eighty children with mean (SD) age 7.6 (0.2) years had mean height-for-age (HAZ) and weight-for-age Z-scores (WAZ) of -0.63 (0.81) and -0.55 (0.85), respectively. Lean mass index and total skinfold thicknesses were related to WAZ and BMI Z-score, but not to HAZ. Total physical score was associated with unit rises in HAZ (1.29, 95% CI 0.75, 1.82, p<0.001), and lean mass index (0.50, 95% CI 0.16, 0.83, p = 0.004), but not skinfold thicknesses. The SAT was associated with unit increases in the mental processing index and child socioemotional score. The caregiver questionnaire identified high levels of adversity and food insecurity., Conclusions: The SAHARAN toolbox provided a feasible and acceptable holistic assessment of child growth and function in mid-childhood. We found clear associations between growth, height-adjusted lean mass and physical function, but not cognitive function. The SAHARAN toolbox could be deployed to characterise school-age growth, development and function elsewhere in sub-Saharan Africa., Competing Interests: The authors have declared that no competing interests exist, (Copyright: © 2023 Piper et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Interest in measuring cognition in children in low-resourced settings has increased in recent years, but options for cognitive assessments are limited. Researchers are faced with challenges when using existing assessments in these settings, such as trained workforce shortages, less relevant testing stimuli, limitations of proprietary assessments, and inadequate parental knowledge of cognitive milestones. Tablet-based direct child assessments are emerging as a practical solution to these challenges, but evidence of their validity and utility in cross-cultural settings is limited. In this overview, we introduce key concepts of this field while exploring the current landscape of tablet-based assessments for low-resourced settings. We also make recommendations for future directions of this relatively novel field. We conclude that tablet-based assessments are an emerging and promising method of assessing cognition in young children. Further awareness and dissemination of validated tablet-based assessments may increase capacity for child development research and clinical practice in low-resourced settings., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: MSM led the adaptation of the NIH Toolbox tests in Dholou and Swahili languages. She was not paid or compensated for this specific work in any formal or consultancy role. DM supported the development and validation of DEEP among preschool children in rural India and was a part of the consortium that developed and validated START. SB co-led the development and validation of DEEP and was also a part of the consortium that developed and validated START. JP has piloted the Plus-EF in rural Zimbabwe. MJG received funding from the Medical Research Council and National Institutes of Health for research which is utilising DEEP in Malawi as well as by Wellcome Trust and Autism Speaks. MJG also has some consultancy funding from the World Health Organisation for support of work on the Global Scales of Early Development (GSED). AK has no COI at this time., (Copyright: © 2023 McHenry et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

For children with acute malnutrition, ready-to-use therapeutic foods (RUTF) are lifesaving treatments. In 2012, detailed testing detected Enterobacteriaceae including Cronobacter species at low levels in RUTF from all UNICEF-approved producers. Cronobacter in milk feeds has previously been associated with severe neonatal infections. Thus, given the susceptibility of severely malnourished children to invasive bacterial infections, concerns arose about the potential for Cronobacter infections from RUTF. This led to widespread production and supply problems in emergency feeding programmes. The KEMRI/Wellcome Trust Research Programme has conducted systematic surveillance for invasive bacterial infections among children admitted to Kilifi County Hospital, Kenya since 1998. 65,426 paediatric blood and cerebrospinal fluid cultures from 52,733 admissions resulted in 3953 with growth of a pathogenic organism. From the 60 Enterobacter and Cronobacter isolates, possible Cronobacter species were initially selected from their original API-20E biochemical profile, which was repeated and then confirmed using ID-32E. Only two isolates were consistent with Cronobacter species, neither case had received RUTF. Serious infection due to Cronobacter species does not have a significant burden in this population. This has important implications for the continued supply, manufacture and monitoring of emergency feeds for malnourished children.

Sodium benzoate and potassium sorbate are extremely useful agents for food and beverage preservation, yet concerns remain over their complete safety. Benzoate can react with the ascorbic acid in drinks to produce the carcinogen benzene. A few children develop allergy to this additive while, as a competitive inhibitor of D-amino acid oxidase, benzoate can also influence neurotransmission and cognitive functioning. Model organism and cell culture studies have raised some issues. Benzoate has been found to exert teratogenic and neurotoxic effects on zebrafish embryos. In addition, benzoate and sorbate are reported to cause chromosome aberrations in cultured human lymphocytes; also to be potently mutagenic toward the mitochondrial DNA in aerobic yeast cells. Whether the substantial human consumption of these compounds could significantly increase levels of such damages in man is still unclear. There is no firm evidence that it is a risk factor in type 2 diabetes. The clinical administration of sodium benzoate is of proven benefit for many patients with urea cycle disorders, while recent studies indicate it may also be advantageous in the treatment of multiple sclerosis, schizophrenia, early-stage Alzheimer's disease and Parkinson's disease. Nevertheless, exposure to high amounts of this agent should be approached with caution, especially since it has the potential to generate a shortage of glycine which, in turn, can negatively influence brain neurochemistry. We discuss here how a small fraction of the population might be rendered-either through their genes or a chronic medical condition-particularly susceptible to any adverse effects of sodium benzoate., (© 2017 Institute of Food Technologists®.)

Introduction: Phenytoin has complex pharmacokinetics. The intravenous loading dose of phenytoin for children in status epilepticus has recently been increased from 18 to 20 mg/kg. There are no data on the clinical effectiveness and safety of this new dose., Methods: The use of intravenous loading doses of phenytoin was audited over 27 months to evaluate the pharmacokinetic, clinical and toxic effects of the new dose in clinical practice. Serum phenytoin concentrations were compared with dose (weight-adjusted) and time., Results: Serum phenytoin concentrations were measured on 48 occasions from 41 children (39 retrospective and 9 prospective), of which 24 were within 60-180 (median 105) minutes following completion of infusion of the loading dose. Use of estimated weights meant patients received between 15.5 and 27.5 mg/kg (78% to 138% expected dose). Supra-therapeutic serum concentrations >20 µg/mL were present in 5/24 (20.1%) (after doses based on actual weight in three and estimated weight in two patients). Three adverse effects consistent with phenytoin toxicity were noted in children with supra-therapeutic concentrations. Two errors in dose prescriptions were found., Conclusions: The majority of serum phenytoin concentrations were in the therapeutic range. Estimating weight in children for the 20 mg/kg intravenous loading dose of phenytoin is often clinically necessary but inaccurate, resulting in up to 138% of the expected and recommended dose in this cohort., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Environmental magnetic proxies provide a rapid means of assessing the degree of industrial heavy metal pollution in soils and sediments. To test the efficiency of magnetic methods for detecting contaminates from a Fe-smelting plant in Loudi City, Hunan Province (China) we investigated river sediments from Lianshui River. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these sediments. Anthropogenic heavy metals coexist with coarse-grained magnetic spherules. It can be demonstrated that the Pollution Load Index of industrial heavy metals (Fe, V, Cr, Mo, Zn, Pb, Cd, Cu) and the logarithm of saturation isothermal remanent magnetization, a proxy for magnetic concentration, are significantly correlated. The distribution heavy metal pollution in the Lianshui River is controlled by surface water transport and deposition. Our findings demonstrate that magnetic methods have a useful and practical application for detecting and mapping pollution in and around modern industrial cities., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Platinum(II) complexes of the form [PtL(n)Cl](+) are reported, containing the N--N--N-coordinating ligands 2,6-di(8-quinolyl)pyridine (L(1)), 2,6-di(8-quinolyl)-4-methoxypyridine (L(2)), or 2,6-di(7-aza-indolyl)-pyridine (L(3)). Metathesis of the chloride co-ligand in [PtL(1)Cl](+) can be accomplished under mild conditions, as exemplified by the formation of the complexes [PtL(1)OMe](+) and [PtL(1)(C[triple bond]C-tfp)](+), in which L(1) remains bound as a terdentate ligand {HC[triple bond]C-tfp = 3,5-bis(trifluoromethyl)-phenylacetylene}. An N--C--N-coordinated, cyclometalated analogue of [PtL(1)Cl](+) has also been prepared, namely, PtL(4)Cl where HL(4) is 1,3-di(8-quinolyl)benzene. The common feature among the six new complexes described here is that they contain 6-membered chelate rings, rather than the usual 5-membered rings that form when more common N--N--N ligands, such as 2,2':6',2''-terpyridine (tpy), bind to Pt(II). All the quinolyl-based complexes are phosphorescent in solution at room temperature, with quantum yields up to 4%. This contrasts with the well-established lack of emission from [Pt(tpy)Cl](+) under these conditions. Density functional theory calculations suggest that the improvement may stem, at least in part, from the relief of ring strain associated with the larger chelate ring size, leading to a more optimal bite angle at the metal, close to 180 degrees , and hence to a stronger ligand field. Consideration of the luminescence parameters, including data at 77 K, together with absorption and electrochemical data and the results of TD-DFT calculations, suggests that the lowest-lying singlet states have metal-to-ligand charge-transfer (MLCT) character, but that the triplet state from which emission occurs has more predominant ligand-centered character. The azaindolyl complex [PtL(3)Cl](+) is not emissive at room temperature, apparently owing to a particularly small radiative rate constant. The cyclometalated complex PtL(4)Cl emits at lower energy than [PtL(1)Cl](+) but, in this case, the luminescence quantum yield is inferior to related complexes with 5-membered chelate rings.

We introduce a versatile method that allows local and repeatable delivery (or depletion) of any water-soluble reagent from a nanopipet in ionic solution to make localized controlled changes in reagent concentration at a surface. In this work, Na(+) or OH(-) ions were dosed from the pipet using pulsed voltage-driven delivery. Total internal reflection fluorescence from CoroNa Green dye in the bath for Na(+) ions or fluorescein in the bath for pH quantified the resulting changes in local surface concentration. These changes had a time response as short as 10 ms and a radius of 1-30 microm and depended on the diameter of the pipet used, the applied voltage, and the pipet-surface separation. After the pipet dosing was characterized in detail, two proof-of-concept experiments on single cells and single molecules were then performed. We demonstrated local control of the sodium-sensitive flagellar motor in single Escherichia coli chimera on the time scale of 1 s by dosing sodium and monitoring the rotation of a 1 microm diameter bead fixed to the flagellum. We also demonstrated triggered single-molecule unfolding by dosing acid from the pipet to locally melt individual molecules of duplex DNA, as observed using fluorescent resonance energy transfer.

Magnetic properties of atmospheric particulate matter collected by both natural and artificial dust receptors are increasingly being used as proxy parameters for environmental analyses. This study reports the first investigation of the relationship between smelting factory activity and the impact on the environment as recorded by the magnetic signature in Salix matsudana tree rings. Magnetic techniques including low-temperature experiments, successive acquisition of isothermal remanent magnetisation (IRM), hysteresis loops and measurements of saturated IRM (SIRM) indicated that magnetic particles were omnipresent in tree bark and trunk wood, and that these particles were predominantly magnetite with multidomain properties. The magnetic properties of tree trunk and branch cores sampled from different directions and heights implied that the acquisition of magnetic particles by a tree depends on both orientation and height. The differences of SIRM values of tree ring cores indicated that pollution source-facing tree trunk wood contained significantly more magnetic particles than other faces. The results indicated that magnetic particles are most likely to be intercepted and collected by tree bark and then enter into tree xylem tissues during the growing season to become finally enclosed into the tree ring by lignification. There was a significant correlation between time-dependent SIRM values of tree ring cores and the annual iron production of the smelting factory. From the dependence of magnetic properties with sampling direction and height, it is argued that magnetic particles in the xylem cannot move between tree rings. Accordingly, the SIRM of tree ring cores from the source-facing side can contribute to historic studies of atmospheric particulate matter produced by heavy metal smelting activities.

Objective: Oxidative stress contributes to the pathogenesis of many diseases, including atherosclerosis and sepsis. We have previously described a novel class of therapeutic compounds with antioxidant and antiinflammatory properties. However, at present, the intracellular targets of these compounds have not been identified. The purpose of this study was to elucidate the mechanism by which 2 structurally-related antioxidants (AGI-1067 and AGI-1095) inhibit LPS induction of tissue factor (TF) expression in human monocytic cells and endothelial cells., Methods and Results: We found that succinobucol (AGI-1067) and AGI-1095 inhibited LPS induction of TF expression in both monocytic cells and endothelial cells. These compounds also reduced LPS induction of nuclear AP-1 and expression of Egr-1 without affecting nuclear translocation of NF-kappaB. Importantly, these antioxidants inhibited LPS activation of the redox-sensitive kinase, apoptosis signal-regulating kinase-1 (ASK1) and the mitogen-activated protein kinases (MAPKs) p38, ERK1/2, and JNK1/2., Conclusions: AGI-1067 and AGI-1095 inhibit TF gene expression in both monocytic cells and endothelial cells through a mechanism that involves the inhibition of the redox-sensitive MAP3K, ASK1. These compounds selectively reduce the activation/induction of MAPK, AP-1, and Egr-1 without affecting NF-kappaB nuclear translocation.

We report the measurement of the surface conductivity of biological macromolecules by dielectrophoretic trapping at the tip of a glass nanopipet. We find that the threshold voltage for trapping is a function of salt concentration and can be directly linked to the effective conductivity of the biomolecule and its solvation shell. The surface conductivities obtained for 20-mer single-stranded DNA, 40-mer double-stranded DNA, and yellow fluorescent protein are 7.9+/-1.9 nS, 5.3+/-0.7 nS, and 21.5+/-1.6 nS, respectively.

A fluorescent nanosensor based on reporter dye molecules trapped in the tip of a nanopipette has been developed. This 100 nm sized nanosensor has been shown to be capable of measuring local pH and mapping sodium concentration with a temporal resolution of a few milliseconds.

We have studied a donor-acceptor fluorophore-labeled DNA switch where the acceptor is Alexa-647, a carbocyanine dye, in solution at the single molecule level to elucidate the fluorescence switching mechanism. The acceptor, which is in an initial high fluorescence trans state, undergoes a photoisomerization reaction resulting in two additional states during its sub-millisecond transit across the probe volume. These two states are assigned to a nonfluorescent triplet trans state that strongly quenches the donor emission and a singlet cis state that blocks the fluorescence resonance energy transfer (FRET) pathway and gives rise to donor-only fluorescence. The formation of these states is faster than the transit time, so that all three states are approximately equally populated under our experimental conditions. The acceptor dye can stick to the DNA in all these states, with the rate of unsticking determining the rate of isomerization into the other states. Measurement of the rate of change of the FRET signal therefore provides information about the fluorophore-DNA intramolecular dynamics. These results explain the large zero peak in the proximity ratio, often seen in single molecule FRET experiments, and suggest that photoinduced effects may be important in single molecule FRET experiments using carbocyanine dyes. They also suggest that for fast photoinduced switching the interactions of the acceptor dye with the DNA and other surfaces should be prevented.

We show that direct coupling of a dye-labelled DNA (acceptor) to a quantum dot (QD) donor significantly reduces the donor-acceptor distance and improves the FRET efficiency: a highly efficient FRET (approximately 88%) at a low acceptor-to-donor ratio of 2 has been achieved at the single-molecule level.

The pathogenesis of chronic inflammatory diseases, including rheumatoid arthritis, is regulated, at least in part, by modulation of oxidation-reduction (redox) homeostasis and the expression of redox-sensitive inflammatory genes including adhesion molecules, chemokines, and cytokines. AGIX-4207 [2-[4-[[1-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1-methylethyl]thio]-2,6-bis(1,1-dimethylethyl)phenoxy]acetic acid] is a novel, orally active, phenolic antioxidant and anti-inflammatory compound with antirheumatic properties. To elucidate its anti-inflammatory mechanisms, we evaluated AGIX-4207 for a variety of cellular, biochemical, and molecular properties. AGIX-4207 exhibited potent antioxidant activity toward lipid peroxides in vitro and displayed enhanced cellular uptake relative to a structurally related drug, probucol. This resulted in potent inhibition of cellular levels of reactive oxygen species in multiple cell types. AGIX-4207 selectively inhibited tumor necrosis factor (TNF)-alpha-inducible levels of the redox-sensitive genes, vascular cell adhesion molecule-1 and monocyte chemoattractant protein-1, with less inhibition of E-selectin, and no effect on intracellular adhesion molecule-1 expression in endothelial cells. In addition, AGIX-4207 inhibited cytokine-induced levels of monocyte chemoattractant protein-1, interleukin (IL)-6, and IL-8 from endothelial cells and human fibroblast-like synoviocytes as well as lipopolysaccharide-induced release of TNF-alpha, IL-1beta, and IL-6 from human peripheral blood mononuclear cells. AGIX-4207 did not inhibit TNF-alpha-induced nuclear translocation of nuclear factor of the kappa-enhancer in B cells (NF-kappaB), suggesting that the mechanism of action is independent of this redox-sensitive transcription factor. Taken together, these results provide a mechanistic framework for understanding the anti-inflammatory and antirheumatic activity of AGIX-4207 and provide further support for the view that inhibition of redox-sensitive inflammatory gene expression is an attractive approach for the treatment of chronic inflammatory diseases.