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1.
Cell ; 185(17): 3263-3277.e15, 2022 08 18.
Article in English | MEDLINE | ID: mdl-35931082

ABSTRACT

Live bacterial therapeutics (LBTs) could reverse diseases by engrafting in the gut and providing persistent beneficial functions in the host. However, attempts to functionally manipulate the gut microbiome of conventionally raised (CR) hosts have been unsuccessful because engineered microbial organisms (i.e., chassis) have difficulty in colonizing the hostile luminal environment. In this proof-of-concept study, we use native bacteria as chassis for transgene delivery to impact CR host physiology. Native Escherichia coli bacteria isolated from the stool cultures of CR mice were modified to express functional genes. The reintroduction of these strains induces perpetual engraftment in the intestine. In addition, engineered native E. coli can induce functional changes that affect physiology of and reverse pathology in CR hosts months after administration. Thus, using native bacteria as chassis to "knock in" specific functions allows mechanistic studies of specific microbial activities in the microbiome of CR hosts and enables LBT with curative intent.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Animals , Bacteria/genetics , Escherichia coli/genetics , Gastrointestinal Microbiome/physiology , Mice , Transgenes
2.
Cell ; 161(7): 1668-80, 2015 Jun 18.
Article in English | MEDLINE | ID: mdl-26091042

ABSTRACT

Lipids play central roles in physiology and disease, where their structural, metabolic, and signaling functions often arise from interactions with proteins. Here, we describe a set of lipid-based chemical proteomic probes and their global interaction map in mammalian cells. These interactions involve hundreds of proteins from diverse functional classes and frequently occur at sites of drug action. We determine the target profiles for several drugs across the lipid-interaction proteome, revealing that its ligandable content extends far beyond traditionally defined categories of druggable proteins. In further support of this finding, we describe a selective ligand for the lipid-binding protein nucleobindin-1 (NUCB1) and show that this compound perturbs the hydrolytic and oxidative metabolism of endocannabinoids in cells. The described chemical proteomic platform thus provides an integrated path to both discover and pharmacologically characterize a wide range of proteins that participate in lipid pathways in cells.


Subject(s)
Lipid Metabolism , Proteins/analysis , Proteins/metabolism , Animals , Calcium-Binding Proteins/analysis , Cell Line, Tumor , DNA-Binding Proteins/analysis , Drug Evaluation, Preclinical , Eicosanoids/metabolism , Endocannabinoids/metabolism , HEK293 Cells , Humans , Lipid Metabolism/drug effects , Mice , Nerve Tissue Proteins/analysis , Nucleobindins , Proteome/analysis , Proteome/metabolism , Small Molecule Libraries/pharmacology
3.
Plant Cell ; 34(11): 4600-4622, 2022 10 27.
Article in English | MEDLINE | ID: mdl-35929080

ABSTRACT

Hemicellulose polysaccharides influence assembly and properties of the plant primary cell wall (PCW), perhaps by interacting with cellulose to affect the deposition and bundling of cellulose fibrils. However, the functional differences between plant cell wall hemicelluloses such as glucomannan, xylan, and xyloglucan (XyG) remain unclear. As the most abundant hemicellulose, XyG is considered important in eudicot PCWs, but plants devoid of XyG show relatively mild phenotypes. We report here that a patterned ß-galactoglucomannan (ß-GGM) is widespread in eudicot PCWs and shows remarkable similarities to XyG. The sugar linkages forming the backbone and side chains of ß-GGM are analogous to those that make up XyG, and moreover, these linkages are formed by glycosyltransferases from the same CAZy families. Solid-state nuclear magnetic resonance indicated that ß-GGM shows low mobility in the cell wall, consistent with interaction with cellulose. Although Arabidopsis ß-GGM synthesis mutants show no obvious growth defects, genetic crosses between ß-GGM and XyG mutants produce exacerbated phenotypes compared with XyG mutants. These findings demonstrate a related role of these two similar but distinct classes of hemicelluloses in PCWs. This work opens avenues to study the roles of ß-GGM and XyG in PCWs.


Subject(s)
Arabidopsis , Xylans , Arabidopsis/genetics , Cell Wall/chemistry , Cellulose
4.
Annu Rev Biochem ; 78: 743-68, 2009.
Article in English | MEDLINE | ID: mdl-19231986

ABSTRACT

The sphingosine 1-phosphate (S1P) receptor signaling system is a productive model system. A hydrophobic zwitterionic lysophospholipid ligand with difficult physical properties interacts with five high-affinity G protein-coupled receptors to generate multiple downstream signals. These signals modulate homeostasis and pathology on a steep agonist concentration-response curve. Ligand presence is essential for vascular development and endothelial integrity, while acute increases in ligand concentrations result in cardiac death. Understanding this integrated biochemical system has exemplified the impact of both genetics and chemistry. Developing specific tools with defined biochemical properties for the reversible modulation of signals in real time has been essential to complement insights gained from genetic approaches that may be irreversible and compensated. Despite its knife-edge between life and death, this system, based in part on receptor subtype-selectivity and in part on differential attenuation of deleterious signals, now appears to be on the cusp of meaningful therapy for multiple sclerosis.


Subject(s)
Receptors, Lysosphingolipid/metabolism , Signal Transduction , Animals , Cardiovascular System/embryology , Cardiovascular System/metabolism , Humans , Lymphoid Tissue/embryology , Lymphoid Tissue/metabolism , Multiple Sclerosis/metabolism , Receptors, Lysosphingolipid/chemistry , Receptors, Lysosphingolipid/genetics
5.
Eur J Neurosci ; 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39210746

ABSTRACT

Exposure to infectious or non-infectious immune activation during early development is a serious risk factor for long-term behavioural dysfunctions. Mouse models of maternal immune activation (MIA) have increasingly been used to address neuronal and behavioural dysfunctions in response to prenatal infections. One commonly employed MIA model involves administering poly(I:C) (polyriboinosinic-polyribocytdilic acid), a synthetic analogue of double-stranded RNA, during gestation, which robustly induces an acute viral-like inflammatory response. Using electroencephalography (EEG) and infrared (IR) activity recordings, we explored alterations in sleep/wake, circadian and locomotor activity patterns on the adult male offspring of poly(I:C)-treated mothers. Our findings demonstrate that these offspring displayed reduced home cage activity during the (subjective) night under both light/dark or constant darkness conditions. In line with this finding, these mice exhibited an increase in non-rapid eye movement (NREM) sleep duration as well as an increase in sleep spindles density. Following sleep deprivation, poly(I:C)-exposed offspring extended NREM sleep duration and prolonged NREM sleep bouts during the dark phase as compared with non-exposed mice. Additionally, these mice exhibited a significant alteration in NREM sleep EEG spectral power under heightened sleep pressure. Together, our study highlights the lasting effects of infection and/or immune activation during pregnancy on circadian activity and sleep/wake patterns in the offspring.

6.
Eur J Neurosci ; 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39032002

ABSTRACT

Sleep/wake cycles intricately shape physiological activities including cognitive brain functions, yet the precise molecular orchestrators of sleep remain elusive. Notably, the clinical impact of benzodiazepine drugs underscores the pivotal role of GABAergic neurotransmission in sleep regulation. However, the specific contributions of distinct GABAA receptor subtypes and their principal scaffolding protein, gephyrin, in sleep dynamics remain unclear. The evolving role of synaptic phospho-proteome alterations at excitatory and inhibitory synapses suggests a potential avenue for modulating gephyrin and, consequently, GABAARs for sleep through on-demand kinase recruitment. Our study unveils the distinctive roles of two prevalent GABAA receptor subtypes, α1- and α2-GABAARs, in influencing sleep duration and electrical sleep activity. Notably, the absence of α1-GABAARs emerges as central in sleep regulation, manifesting significant alterations in both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep during dark or active phases, accompanied by altered electroencephalogram (EEG) patterns across various frequencies. Gephyrin proteomics analysis reveals sleep/wake-dependent interactions with a repertoire of known and novel kinases. Crucially, we identify the regulation of gephyrin interaction with ERK1/2, and phosphorylations at serines 268 and 270 are dictated by sleep/wake cycles. Employing AAV-eGFP-gephyrin or its phospho-null variant (S268A/S270A), we disrupt sleep either globally or locally to demonstrate gephyrin phosphorylation as a sleep regulator. In summary, our findings support the local cortical sleep hypothesis and we unveil a molecular mechanism operating at GABAergic synapses, providing critical insights into the intricate regulation of sleep.

7.
Eur J Neurosci ; 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39205434

ABSTRACT

While it is generally known that metabolic disorders and circadian dysfunction are intertwined, how the two systems affect each other is not well understood, nor are the genetic factors that might exacerbate this pathological interaction. Blood chemistry is profoundly changed in metabolic disorders, and we have previously shown that serum factors change cellular clock properties. To investigate if circulating factors altered in metabolic disorders have circadian modifying effects, and whether these effects are of genetic origin, we measured circadian rhythms in U2OS cell in the presence of serum collected from diabetic, obese or control subjects. We observed that circadian period lengthening in U2OS cells was associated with serum chemistry that is characteristic of insulin resistance. Characterizing the genetic variants that altered circadian period length by genome-wide association analysis, we found that one of the top variants mapped to the E3 ubiquitin ligase MARCH1 involved in insulin sensitivity. Confirming our data, the serum circadian modifying variants were also enriched in type 2 diabetes and chronotype variants identified in the UK Biobank cohort. Finally, to identify serum factors that might be involved in period lengthening, we performed detailed metabolomics and found that the circadian modifying variants are particularly associated with branched chain amino acids, whose levels are known to correlate with diabetes and insulin resistance. Overall, our multi-omics data showed comprehensively that systemic factors serve as a path through which metabolic disorders influence circadian system, and these can be examined in human populations directly by simple cellular assays in common cultured cells.

8.
Br J Surg ; 111(3)2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38488204

ABSTRACT

BACKGROUND: Numerous surgical approaches exist for the treatment of pilonidal disease. Current literature on treatment is of poor quality, limiting the ability to define optimal intervention. The aim of this study was to provide real-world data on current surgical practice and report patient and risk-adjusted outcomes, informing future trial design. METHODS: This UK-wide multicentre prospective cohort study, including patients (aged over 16 years) who had definitive treatment for symptomatic pilonidal disease, was conducted between May 2019 and March 2022. Patient and disease characteristics, and intervention details were analysed. Data on patient-reported outcomes, including pain, complications, treatment failure, wound issues, and quality of life, were gathered at various time points up to 6 months after surgery. Strategies were implemented to adjust for risk influencing different treatment choices and outcomes. RESULTS: Of the 667 participants consenting, 574 (86.1%) were followed up to the study end. Twelve interventions were observed. Broadly, 59.5% underwent major excisional surgery and 40.5% minimally invasive surgery. Complications occurred in 45.1% of the cohort. Those who had minimally invasive procedures had better quality of life and, after risk adjustment, less pain (score on day 1: mean difference 1.58, 95% c.i. 1.14 to 2.01), fewer complications (difference 17.5 (95% c.i. 9.1 to 25.9)%), more rapid return to normal activities (mean difference 25.9 (18.4 to 33.4) days) but a rate of higher treatment failure (difference 9.6 (95% c.i. 17.3 to 1.9)%). At study end, 25% reported an unhealed wound and 10% had not returned to normal activities. CONCLUSION: The burden after surgery for pilonidal disease is high and treatment failure is common. Minimally invasive techniques may improve outcomes at the expense of a 10% higher risk of treatment failure.


Subject(s)
Pilonidal Sinus , Humans , Aged , Treatment Outcome , Prospective Studies , Pilonidal Sinus/surgery , Quality of Life , Neoplasm Recurrence, Local , Pain , Recurrence
9.
AIDS Behav ; 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39225889

ABSTRACT

We sought to investigate the association between hazardous alcohol use and gaps in care for people living with HIV over a long-term follow-up period. Adults who had participated in our previously published Phase I study of hazardous alcohol use at HIV programs in Kenya and Uganda were eligible at their 42 to 48 month follow-up visit. Those who re-enrolled were followed for an additional ~ 12 months. Hazardous alcohol use behavior was measured using the Alcohol Use Disorders Identification Test (AUDIT) tool. Deidentified clinical data were used to assess gaps in care (defined as failure to return to clinic within 60 days after a missed visit). The proportion of patients experiencing a gap in care at a specific time point was based on a nonparametric moment-based estimator. A semiparametric Cox proportional hazard model was used to determine the association between hazardous alcohol use at enrollment in Phase I (AUDIT score ≥ 8) and gaps in care. Of the 731 study-eligible participants from Phase I, 5.5% had died, 10.1% were lost to follow-up, 39.5% transferred, 7.5% declined/not approached, and 37.3% were enrolled. Phase II participants were older, had less hazardous drinking and had a lower WHO clinical stage than those not re-enrolled. Hazardous drinking in the re-enrolled was associated with a Hazard Ratio (HR) of 1.88 [p-value = 0.016] for a gap in care. Thus, hazardous alcohol use at baseline was associated with an increased risk of experiencing a gap in care and presents an early target for intervention.


RESUMEN: Buscamos investigar la asociación entre el uso riesgoso de alcohol y retención en programas de VIH a largo plazo. Todo adulto que participó en nuestro estudio previamente publicado sobre el uso riesgoso de alcohol en programas de VIH en Kenia y Uganda era elegible a los 42 a 48 meses de seguimiento. Los adultos reinscritos en la fueron seguidos por ~ 12 meses adicionales. Usamos el "Alcohol Use Disorders Identification Test" (AUDIT) para medir uso de alcohol. Usamos datos clínicos anonimizados para evaluar interrupciones en cuidado (definido como falta de regresar a clínica 60 días después de faltar a una cita). Basamos la proporción de pacientes con una interrupción en cuidado clínico en un estimador momentáneo y no-paramétrico. Determinamos la asociación entre el uso riesgoso de alcohol al inicio de la primera fase (puntuación AUDIT ≥8) con retención en servicios clínicos usando un modelo de riesgo Cox semiparamétrico. De los 731 participantes elegibles, 5.5% habían muerto, 10.1% fueron perdidos a seguimiento clínico, 39.5% se transfirieron a otro programa, 7.5% declinaron participación o no fueron reclutados y 37.3% fueron reinscritos en la segunda fase. Los participantes reinscritos eran mayores, tenían menos uso riesgoso de alcohol y tenían VIH menos avanzado. El uso peligroso del alcohol se vio asociado con el riesgo de tener una interrupción en cuidado clínico [Proporción de Riesgo (Hazard Ratio, HR) PR=1.88, valor-p = 0.016]. Por lo tanto, el uso peligroso del alcohol incrementa el riesgo de perder seguimiento clínico y presenta una oportunidad para intervención.

10.
J Phys Chem A ; 128(10): 1793-1816, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38427685

ABSTRACT

The Δδ regression approach of Blade et al. [ J. Phys. Chem. A 2020, 124(43), 8959-8977] for accurately discriminating between solid forms using a combination of experimental solution- and solid-state NMR data with density functional theory (DFT) calculation is here extended to molecules with multiple conformational degrees of freedom, using furosemide polymorphs as an exemplar. As before, the differences in measured 1H and 13C chemical shifts between solution-state NMR and solid-state magic-angle spinning (MAS) NMR (Δδexperimental) are compared to those determined by gauge-including projector augmented wave (GIPAW) calculations (Δδcalculated) by regression analysis and a t-test, allowing the correct furosemide polymorph to be precisely identified. Monte Carlo random sampling is used to calculate solution-state NMR chemical shifts, reducing computation times by avoiding the need to systematically sample the multidimensional conformational landscape that furosemide occupies in solution. The solvent conditions should be chosen to match the molecule's charge state between the solution and solid states. The Δδ regression approach indicates whether or not correlations between Δδexperimental and Δδcalculated are statistically significant; the approach is differently sensitive to the popular root mean squared error (RMSE) method, being shown to exhibit a much greater dynamic range. An alternative method for estimating solution-state NMR chemical shifts by approximating the measured solution-state dynamic 3D behavior with an ensemble of 54 furosemide crystal structures (polymorphs and cocrystals) from the Cambridge Structural Database (CSD) was also successful in this case, suggesting new avenues for this method that may overcome its current dependency on the prior determination of solution dynamic 3D structures.

11.
Colorectal Dis ; 2024 Apr 21.
Article in English | MEDLINE | ID: mdl-38644667

ABSTRACT

AIM: Research in pilonidal disease faces several challenges, one of which is consistent and useful disease classification. The International Pilonidal Society (IPS) proposed a four-part classification in 2017. The aim of this work was to assess the validity and reliability of this tool using data from the PITSTOP cohort study. METHOD: Face validity was assessed by mapping the items/domains in the IPS tool against tools identified through a systematic review. Key concepts were defined as those appearing in more than two-thirds of published tools. Concurrent and predictive validity were assessed by comparing key patient-reported outcome measures between groups at baseline and at clinic visit. The outcomes of interest were health utility, Cardiff Wound Impact Questionnaire (CWIQ) and pain score between groups. Significance was set at p = 0.05 a priori. Interrater reliability was assessed using images captured during the PITSTOP cohort. Ninety images were assessed by six raters (two experts, two general surgeons and two trainees), and classified into IPS type. Interrater reliability was assessed using the unweighted kappa and unweighted Gwet's AC1 statistics. RESULTS: For face validity items represented in the IPS were common to other classification systems. Concurrent and predictive validity assessment showed differences in health utility and pain between groups at baseline, and for some treatment groups at follow-up. Assessors agreed the same classification in 38% of participants [chance-corrected kappa 0.52 (95% CI 0.42-0.61), Gwet's AC1 0.63 (95% CI 0.56-0.69)]. CONCLUSION: The IPS classification demonstrates key aspects of reliability and validity that would support its implementation.

12.
Colorectal Dis ; 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38671581

ABSTRACT

AIM: Pilonidal sinus disease is a common condition treated by colorectal surgeons. There is a lack of literature in the field to guide optimal management of this condition. As part of the PITSTOP study, we aimed to identify policy and research priorities to provide direction to the field. METHOD: Patients and surgeons were invited to participate. A 'So what, now what' exercise was conducted, informed by data from PITSTOP. This generated statements for research and practice priorities. A three-round online Delphi study was conducted, ranking statements based on policy and research separately. Statements were rated 1 (not important) to 9 (important). Statements that were rated 7-9 by more than 70% of participants were entered into the consensus meeting. Personalized voting feedback was shown between rounds. A face-to-face meeting was held to discuss statements, and participants were asked to rank statements using a weighted choice vote. RESULTS: Twenty-two people participated in the focus group, generating 14 research and 19 policy statements. Statements were voted on by 56 participants in round 1, 53 in round 2 and 51 in round 3. A total of 15 policy statements and 19 research statements were discussed in the consensus round. Key policy statements addressed treatment strategies and intensity, surgeon training opportunities, need for classification and the impact of treatment on return to work. Research recommendations included design of future trials, methodology considerations and research questions. CONCLUSION: This study has identified research and policy priorities in pilonidal sinus disease which are relevant to patients and clinicians. These should inform practice and future research.

13.
BMC Health Serv Res ; 24(1): 687, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816829

ABSTRACT

INTRODUCTION: Rates of substance use are high among youth involved in the legal system (YILS); however, YILS are less likely to initiate and complete substance use treatment compared to their non legally-involved peers. There are multiple steps involved in connecting youth to needed services, from screening and referral within the juvenile legal system to treatment initiation and completion within the behavioral health system. Understanding potential gaps in the care continuum requires data and decision-making from these two systems. The current study reports on the development of data dashboards that integrate these systems' data to help guide decisions to improve substance use screening and treatment for YILS, focusing on end-user feedback regarding dashboard utility. METHODS: Three focus groups were conducted with n = 21 end-users from juvenile legal systems and community mental health centers in front-line positions and in decision-making roles across 8 counties to gather feedback on an early version of the data dashboards; dashboards were then modified based on feedback. RESULTS: Qualitative analysis revealed topics related to (1) important aesthetic features of the dashboard, (2) user features such as filtering options and benchmarking to compare local data with other counties, and (3) the centrality of consistent terminology for data dashboard elements. Results also revealed the use of dashboards to facilitate collaboration between legal and behavioral health systems. CONCLUSIONS: Feedback from end-users highlight important design elements and dashboard utility as well as the challenges of working with cross-system and cross-jurisdiction data.


Subject(s)
Focus Groups , Qualitative Research , Substance-Related Disorders , Humans , Adolescent , Substance-Related Disorders/therapy , Male , Female , Juvenile Delinquency/legislation & jurisprudence , Continuity of Patient Care
14.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Article in English | MEDLINE | ID: mdl-34341119

ABSTRACT

Decades of air quality improvements have substantially reduced the motor vehicle emissions of volatile organic compounds (VOCs). Today, volatile chemical products (VCPs) are responsible for half of the petrochemical VOCs emitted in major urban areas. We show that VCP emissions are ubiquitous in US and European cities and scale with population density. We report significant VCP emissions for New York City (NYC), including a monoterpene flux of 14.7 to 24.4 kg ⋅ d-1 ⋅ km-2 from fragranced VCPs and other anthropogenic sources, which is comparable to that of a summertime forest. Photochemical modeling of an extreme heat event, with ozone well in excess of US standards, illustrates the significant impact of VCPs on air quality. In the most populated regions of NYC, ozone was sensitive to anthropogenic VOCs (AVOCs), even in the presence of biogenic sources. Within this VOC-sensitive regime, AVOCs contributed upwards of ∼20 ppb to maximum 8-h average ozone. VCPs accounted for more than 50% of this total AVOC contribution. Emissions from fragranced VCPs, including personal care and cleaning products, account for at least 50% of the ozone attributed to VCPs. We show that model simulations of ozone depend foremost on the magnitude of VCP emissions and that the addition of oxygenated VCP chemistry impacts simulations of key atmospheric oxidation products. NYC is a case study for developed megacities, and the impacts of VCPs on local ozone are likely similar for other major urban regions across North America or Europe.


Subject(s)
Air Pollutants/analysis , Ozone , Volatile Organic Compounds/analysis , Air Pollutants/chemistry , Air Pollution , Cities , Environmental Monitoring/methods , Europe , Humans , Models, Theoretical , Monoterpenes/analysis , New York City , Nitrogen Oxides/analysis , Nitrogen Oxides/chemistry , Odorants/analysis , Population Density , Vehicle Emissions/analysis , Volatile Organic Compounds/chemistry
15.
Proc Natl Acad Sci U S A ; 118(52)2021 12 28.
Article in English | MEDLINE | ID: mdl-34930838

ABSTRACT

Ozone is the third most important anthropogenic greenhouse gas after carbon dioxide and methane but has a larger uncertainty in its radiative forcing, in part because of uncertainty in the source characteristics of ozone precursors, nitrogen oxides, and volatile organic carbon that directly affect ozone formation chemistry. Tropospheric ozone also negatively affects human and ecosystem health. Biomass burning (BB) and urban emissions are significant but uncertain sources of ozone precursors. Here, we report global-scale, in situ airborne measurements of ozone and precursor source tracers from the NASA Atmospheric Tomography mission. Measurements from the remote troposphere showed that tropospheric ozone is regularly enhanced above background in polluted air masses in all regions of the globe. Ozone enhancements in air with high BB and urban emission tracers (2.1 to 23.8 ppbv [parts per billion by volume]) were generally similar to those in BB-influenced air (2.2 to 21.0 ppbv) but larger than those in urban-influenced air (-7.7 to 6.9 ppbv). Ozone attributed to BB was 2 to 10 times higher than that from urban sources in the Southern Hemisphere and the tropical Atlantic and roughly equal to that from urban sources in the Northern Hemisphere and the tropical Pacific. Three independent global chemical transport models systematically underpredict the observed influence of BB on tropospheric ozone. Potential reasons include uncertainties in modeled BB injection heights and emission inventories, export efficiency of BB emissions to the free troposphere, and chemical mechanisms of ozone production in smoke. Accurately accounting for intermittent but large and widespread BB emissions is required to understand the global tropospheric ozone burden.


Subject(s)
Air Pollutants , Air Pollution , Biomass , Ozone , Air Pollutants/analysis , Air Pollutants/chemistry , Atmosphere , Ecosystem , Fires , Ozone/analysis , Ozone/chemistry
16.
Chemphyschem ; 24(3): e202200558, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36195553

ABSTRACT

Crystallographic disorder, whether static or dynamic, can be detrimental to the physical and chemical stability, ease of crystallization and dissolution rate of an active pharmaceutical ingredient. Disorder can result in a loss of manufacturing control leading to batch-to-batch variability and can lengthen the process of structural characterization. The range of NMR active nuclei makes solid-state NMR a unique technique for gaining nucleus-specific information about crystallographic disorder. Here, we explore the use of high-field 35 Cl solid-state NMR at 23.5 T to characterize both static and dynamic crystallographic disorder: specifically, dynamic disorder occurring in duloxetine hydrochloride (1), static disorder in promethazine hydrochloride (2), and trifluoperazine dihydrochloride (3). In all structures, the presence of crystallographic disorder was confirmed by 13 C cross-polarization magic-angle spinning (CPMAS) NMR and supported by GIPAW-DFT calculations, and in the case of 3, 1 H solid-state NMR provided additional confirmation. Applying 35 Cl solid-state NMR to these compounds, we show that higher magnetic fields are beneficial for resolving the crystallographic disorder in 1 and 3, while broad spectral features were observed in 2 even at higher fields. Combining the data obtained from 1 H, 13 C, and 35 Cl NMR, we show that 3 exhibits a unique case of disorder involving the + N-H hydrogen positions of the piperazinium ring, driving the chloride anions to occupy three distinct sites.


Subject(s)
Chlorides , Magnetic Resonance Imaging , Humans , Magnetic Resonance Spectroscopy/methods , Pharmaceutical Preparations
17.
Environ Sci Technol ; 2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36607321

ABSTRACT

Increasing trends in biomass burning emissions significantly impact air quality in North America. Enhanced mixing ratios of ozone (O3) in urban areas during smoke-impacted periods occur through transport of O3 produced within the smoke or through mixing of pyrogenic volatile organic compounds (PVOCs) with urban nitrogen oxides (NOx = NO + NO2) to enhance local O3 production. Here, we analyze a set of detailed chemical measurements, including carbon monoxide (CO), NOx, and speciated volatile organic compounds (VOCs), to evaluate the effects of smoke transported from relatively local and long-range fires on O3 measured at a site in Boulder, Colorado, during summer 2020. Relative to the smoke-free period, CO, background O3, OH reactivity, and total VOCs increased during both the local and long-range smoke periods, but NOx mixing ratios remained approximately constant. These observations are consistent with transport of PVOCs (comprised primarily of oxygenates) but not NOx with the smoke and with the influence of O3 produced within the smoke upwind of the urban area. Box-model calculations show that local O3 production during all three periods was in the NOx-sensitive regime. Consequently, this locally produced O3 was similar in all three periods and was relatively insensitive to the increase in PVOCs. However, calculated NOx sensitivities show that PVOCs substantially increase O3 production in the transition and NOx-saturated (VOC-sensitive) regimes. These results suggest that (1) O3 produced during smoke transport is the main driver for O3 increases in NOx-sensitive urban areas and (2) smoke may cause an additional increase in local O3 production in NOx-saturated (VOC-sensitive) urban areas. Additional detailed VOC and NOx measurements in smoke impacted urban areas are necessary to broadly quantify the effects of wildfire smoke on urban O3 and develop effective mitigation strategies.

18.
Environ Sci Technol ; 57(5): 1870-1881, 2023 02 07.
Article in English | MEDLINE | ID: mdl-36695819

ABSTRACT

We report aircraft observations of extreme levels of HCl and the dihalogens Cl2, Br2, and BrCl in an industrial plume near the Great Salt Lake, Utah. Complete depletion of O3 was observed concurrently with halogen enhancements as a direct result of photochemically produced halogen radicals. Observed fluxes for Cl2, HCl, and NOx agreed with facility-reported emissions inventories. Bromine emissions are not required to be reported in the inventory, but are estimated as 173 Mg year-1 Br2 and 949 Mg year-1 BrCl, representing a major uncounted oxidant source. A zero-dimensional photochemical box model reproduced the observed O3 depletions and demonstrated that bromine radical cycling was principally responsible for the rapid O3 depletion. Inclusion of observed halogen emissions in both the box model and a 3D chemical model showed significant increases in oxidants and particulate matter (PM2.5) in the populated regions of the Great Salt Lake Basin, where winter PM2.5 is among the most severe air quality issues in the U.S. The model shows regional PM2.5 increases of 10%-25% attributable to this single industrial halogen source, demonstrating the impact of underreported industrial bromine emissions on oxidation sources and air quality within a major urban area of the western U.S.


Subject(s)
Air Pollutants , Air Pollution , Ozone Depletion , Ozone , Air Pollutants/analysis , Halogens , Ozone/analysis , Bromine , Lakes , Air Pollution/analysis , Particulate Matter/analysis , Oxidants
19.
Colorectal Dis ; 25(10): 2010-2016, 2023 10.
Article in English | MEDLINE | ID: mdl-37583061

ABSTRACT

AIM: Pilonidal sinus is a common surgical condition which impacts a young and economically active population. There are limited data to guide treatment in this condition. The aim of this work was to assess current practice. METHOD: A survey was developed as part of the PITSTOP study. It included questions on volume of practice, treatment preferences and training. The survey was delivered to consultant surgeons with a UK practice through social media, specialty surgical societies and through PITSTOP sites. Descriptive statistics were reported. RESULTS: Of the 200 people who received a link to the questionnaire, 109 completed it (response rate 54.5%). Respondents treated a median of 15 patients per year, with 20% of these having recurrent disease. Estimates of recurrence were higher than reported in the literature and higher than in a survey 10 years ago. Nearly 50% of surgeons advocate nonsurgical treatment in some patients despite limited evidence. Two thirds practised interventions not favoured by guidelines, including excision and leave open and midline closure techniques. Invasive procedures tended to be favoured when minimally invasive procedures may be appropriate. Surgical training programmes were the key training setting for commonly offered procedures, with few other training opportunities reported. For some procedures, no formal training had been given. CONCLUSION: This survey highlights issues with quality in pilonidal surgery in the UK, with persistence of potentially outdated techniques, no consistent treatment escalation plan, a suggestion of under- or overtreatment of disease and a high perception of failure. This may relate to the current system of training and lack of evidence-based guidance.


Subject(s)
Pilonidal Sinus , Surgeons , Humans , Pilonidal Sinus/surgery , Neoplasm Recurrence, Local , Surveys and Questionnaires , United Kingdom , Recurrence , Treatment Outcome
20.
Colorectal Dis ; 2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36636796

ABSTRACT

BACKGROUND: A range of treatments are available for pilonidal sinus disease (PSD), each of which has a different risk/benefit profile. The aim of this study was to collect patient views on which interventions they would rather avoid and which outcomes they most value for PSD. METHOD: We conducted an online survey using the discrete choice experiment (DCE) method. DCE task involved participants choosing the best treatment option when presented with a set of competing hypothetical treatment profiles. Participants with symptomatic PSD, referred for elective surgery were recruited from 33 NHS trusts between 2020 and 2022. Collected DCE data were analysed using regression analyses. RESULTS: One hundred and eleven participants completed the survey. In the overall group, low risk of infection/persistence was the most important characteristic when making a treatment decision (attribute importance score of 70%), followed by treatments with shorter recovery time with an attribute importance score of 30%. The results demonstrated that patients are willing to accept trade-offs between treatment recovery time and risk of infection/persistence. Patients above 30 years old are willing to accept a higher chance of treatment failure in exchange for rapid treatment recovery (risk tolerance between 22.35 - 34.67 percentage points). Conversely, patients in the younger age groups, were risk averse, and were only willing to accept a small risk 1.51-2.15 in exchange for a treatment with faster recovery time. All patient groups appear to the reject the excision and leave open technique due to the need for protracted nursing care. CONCLUSION: This study highlights the need for shared decision making when it comes to surgery for PSD.

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