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1.
Proc Natl Acad Sci U S A ; 121(24): e2320215121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38830103

RESUMO

The Kuiper Belt object (KBO) Arrokoth, the farthest object in the Solar System ever visited by a spacecraft, possesses a distinctive reddish surface and is characterized by pronounced spectroscopic features associated with methanol. However, the fundamental processes by which methanol ices are converted into reddish, complex organic molecules on Arrokoth's surface have remained elusive. Here, we combine laboratory simulation experiments with a spectroscopic characterization of methanol ices exposed to proxies of galactic cosmic rays (GCRs). Our findings reveal that the surface exposure of methanol ices at 40 K can replicate the color slopes of Arrokoth. Sugars and their derivatives (acids, alcohols) with up to six carbon atoms, including glucose and ribose-fundamental building block of RNA-were ubiquitously identified. In addition, polycyclic aromatic hydrocarbons (PAHs) with up to six ring units (13C22H12) were also observed. These sugars and their derivatives along with PAHs connected by unsaturated linkers represent key molecules rationalizing the reddish appearance of Arrokoth. The formation of abundant sugar-related molecules dubs Arrokoth as a sugar world and provides a plausible abiotic preparation route for a key class of biorelevant molecules on the surface of KBOs prior to their delivery to prebiotic Earth.

2.
Lancet ; 403(10433): 1279-1289, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38492578

RESUMO

BACKGROUND: Individuals with rare kidney diseases account for 5-10% of people with chronic kidney disease, but constitute more than 25% of patients receiving kidney replacement therapy. The National Registry of Rare Kidney Diseases (RaDaR) gathers longitudinal data from patients with these conditions, which we used to study disease progression and outcomes of death and kidney failure. METHODS: People aged 0-96 years living with 28 types of rare kidney diseases were recruited from 108 UK renal care facilities. The primary outcomes were cumulative incidence of mortality and kidney failure in individuals with rare kidney diseases, which were calculated and compared with that of unselected patients with chronic kidney disease. Cumulative incidence and Kaplan-Meier survival estimates were calculated for the following outcomes: median age at kidney failure; median age at death; time from start of dialysis to death; and time from diagnosis to estimated glomerular filtration rate (eGFR) thresholds, allowing calculation of time from last eGFR of 75 mL/min per 1·73 m2 or more to first eGFR of less than 30 mL/min per 1·73 m2 (the therapeutic trial window). FINDINGS: Between Jan 18, 2010, and July 25, 2022, 27 285 participants were recruited to RaDaR. Median follow-up time from diagnosis was 9·6 years (IQR 5·9-16·7). RaDaR participants had significantly higher 5-year cumulative incidence of kidney failure than 2·81 million UK patients with all-cause chronic kidney disease (28% vs 1%; p<0·0001), but better survival rates (standardised mortality ratio 0·42 [95% CI 0·32-0·52]; p<0·0001). Median age at kidney failure, median age at death, time from start of dialysis to death, time from diagnosis to eGFR thresholds, and therapeutic trial window all varied substantially between rare diseases. INTERPRETATION: Patients with rare kidney diseases differ from the general population of individuals with chronic kidney disease: they have higher 5-year rates of kidney failure but higher survival than other patients with chronic kidney disease stages 3-5, and so are over-represented in the cohort of patients requiring kidney replacement therapy. Addressing unmet therapeutic need for patients with rare kidney diseases could have a large beneficial effect on long-term kidney replacement therapy demand. FUNDING: RaDaR is funded by the Medical Research Council, Kidney Research UK, Kidney Care UK, and the Polycystic Kidney Disease Charity.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Insuficiência Renal , Humanos , Taxa de Filtração Glomerular , Rim , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Falência Renal Crônica/etiologia , Radar , Doenças Raras , Sistema de Registros , Insuficiência Renal/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/complicações , Reino Unido/epidemiologia , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
3.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969838

RESUMO

Geminal diols-organic molecules carrying two hydroxyl groups at the same carbon atom-have been recognized as key reactive intermediates by the physical (organic) chemistry and atmospheric science communities as fundamental transients in the aerosol cycle and in the atmospheric ozonolysis reaction sequence. Anticipating short lifetimes and their tendency to fragment to water plus the aldehyde or ketone, free geminal diols represent one of the most elusive classes of organic reactive intermediates. Here, we afford an exceptional glance into the preparation of the previously elusive methanediol [CH2(OH)2] transient-the simplest geminal diol-via energetic processing of low-temperature methanol-oxygen ices. Methanediol was identified in the gas phase upon sublimation via isomer-selective photoionization reflectron time-of-flight mass spectrometry combined with isotopic substitution studies. Electronic structure calculations reveal that methanediol is formed via excited state dynamics through insertion of electronically excited atomic oxygen into a carbon-hydrogen bond of the methyl group of methanol followed by stabilization in the icy matrix. The first preparation and detection of methanediol demonstrates its gas-phase stability as supported by a significant barrier hindering unimolecular decomposition to formaldehyde and water. These findings advance our perception of the fundamental chemistry and chemical bonding of geminal diols and signify their role as an efficient sink of aldehydes and ketones in atmospheric environments eventually coupling the atmospheric chemistry of geminal diols and Criegee intermediates.

4.
Proc Natl Acad Sci U S A ; 119(43): e2210617119, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36252022

RESUMO

Carbonate mud represents one of the most important geochemical archives for reconstructing ancient climatic, environmental, and evolutionary change from the rock record. Mud also represents a major sink in the global carbon cycle. Yet, there remains no consensus about how and where carbonate mud is formed. Here, we present stable isotope and trace-element data from carbonate constituents in the Bahamas, including ooids, corals, foraminifera, and algae. We use geochemical fingerprinting to demonstrate that carbonate mud cannot be sourced from the abrasion and mixture of any combination of these macroscopic grains. Instead, an inverse Bayesian mixing model requires the presence of an additional aragonite source. We posit that this source represents a direct seawater precipitate. We use geological and geochemical data to show that "whitings" are unlikely to be the dominant source of this precipitate and, instead, present a model for mud precipitation on the bank margins that can explain the geographical distribution, clumped-isotope thermometry, and stable isotope signature of carbonate mud. Next, we address the enigma of why mud and ooids are so abundant in the Bahamas, yet so rare in the rest of the world: Mediterranean outflow feeds the Bahamas with the most alkaline waters in the modern ocean (>99.7th-percentile). Such high alkalinity appears to be a prerequisite for the nonskeletal carbonate factory because, when Mediterranean outflow was reduced in the Miocene, Bahamian carbonate export ceased for 3-million-years. Finally, we show how shutting off and turning on the shallow carbonate factory can send ripples through the global climate system.


Assuntos
Carbonatos , Sedimentos Geológicos , Teorema de Bayes , Carbonato de Cálcio , Carbonatos/análise , Água do Mar
5.
J Am Chem Soc ; 146(17): 12174-12184, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629886

RESUMO

Orthocarboxylic acids─organic molecules carrying three hydroxyl groups at the same carbon atom─have been distinguished as vital reactive intermediates by the atmospheric science and physical (organic) chemistry communities as transients in the atmospheric aerosol cycle. Predicted short lifetimes and their tendency to dehydrate to a carboxylic acid, free orthocarboxylic acids, signify one of the most elusive classes of organic reactive intermediates, with even the simplest representative methanetriol (CH(OH)3)─historically known as orthoformic acid─not previously been detected experimentally. Here, we report the first synthesis of the previously elusive methanetriol molecule in low-temperature mixed methanol (CH3OH) and molecular oxygen (O2) ices subjected to energetic irradiation. Supported by electronic structure calculations, methanetriol was identified in the gas phase upon sublimation via isomer-selective photoionization reflectron time-of-flight mass spectrometry combined with isotopic substitution studies and the detection of photoionization fragments. The first synthesis and detection of methanetriol (CH(OH)3) reveals its gas-phase stability as supported by a significant barrier hindering unimolecular decomposition. These findings progress our fundamental understanding of the chemistry and chemical bonding of methanetriol, hydroxyperoxymethane (CH3OOOH), and hydroxyperoxymethanol (CH2(OH)OOH), which are all prototype molecules in the oxidation chemistry of the atmosphere.

6.
Environ Geochem Health ; 46(7): 244, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851657

RESUMO

HIGHLIGHTS: Microplastics (MPs) and microrubbers (MRs) determined in lichens and mosses around Shiraz. In lichens, MPs mainly thin fibres up to 1 MP g-1; MRs were < 0.1 MP g-1. In mosses, abundances were similar but with a greater fraction of larger, non-fibrous particles. Larger MPs and MRs decreased in abundance with distance and elevation from Shiraz. Around Shiraz, the common moss, Grimmia critina, would be the most suitable biomonitor. Lichens and mosses have been employed as biomonitors of atmospheric particulate pollutants, like metals and industrial solids, for many decades. Here, we evaluated the potential of nine species of crustose and foliose lichens and a widely distributed moss (Grimmia critina) to act as biomonitors of airborne microplastics (MPs) and microrubbers (MRs). About 200 lichens and 40 mosses were sampled across different altitudinal transects in the vicinity of Shiraz City, southwest Iran, and MPs and MRs were quantified and characterised after sample peroxidation. In most species of lichen, MP and MR abundance overall was < 1 g-1 and < 0.1 g-1, respectively, and the majority of plastics were fibres of < 10 µm in diameter and < 1000 µm in length. Respective weight normalised abundances of MPs and MRs were similar in G. critina, but there were greater proportions of both larger (> 1000 µm) and non-fibrous particles among the MPs. In both lichens and moss, there was a greater number of larger MPs and MRs at locations closest to and at the same elevation as Shiraz than at more distant and elevated locations, suggesting an inverse relationship between particle size and distance travelled. Among the lichens, members of the genus Acarospora, with their areolated form, appeared to act as the most suitable biomonitors for MPs and MRs. Overall, however, the wide distribution of the moss, G. crinita, and its ability to intercept and accumulate a broader range of sizes and shapes of MPs and MRs make this species a better choice, at least in the type of environment studied.


Assuntos
Poluentes Atmosféricos , Briófitas , Líquens , Microplásticos , Líquens/química , Irã (Geográfico) , Microplásticos/análise , Poluentes Atmosféricos/análise , Briófitas/química , Monitoramento Ambiental/métodos , Monitoramento Biológico/métodos , Tamanho da Partícula
7.
J Infect Dis ; 227(2): 183-192, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36214840

RESUMO

We document that 3 human-infectious trematodes and their introduced first intermediate host snail (Melanoides tuberculata) are widespread throughout southern California. We surveyed 41 fishing localities, 19 of which harbored snails infected with zoonotic trematodes. Two of the parasites, Haplorchis pumilio and Centrocestus formosanus, are fishborne intestinal trematodes recognized as being important human pathogens in other areas of the world; the third, Philophthalmus gralli, can infect the human eye. An additional 5 species detected infecting M. tuberculata are likely of little direct threat to people; however, they may be recently introduced to the Americas, highlighting the risk that additional pathogenic trematodes transmitted by the snail in its native range could be introduced to the United States. The current, possible human-infection risk in California clarifies the need to consider the introduced snail and its parasites from a public health perspective anywhere in the United States the snail has been introduced.


We report that 3 human-infecting trematodes and their introduced intermediate host snail are widespread in southern California freshwater fishing localities. Eating undercooked or underfrozen fish is the way people get infected by 2 of the parasite species, which are recognized as important human pathogens in other areas of the world. We also found 5 non­human-infectious trematodes carried by the snail that may be cointroduced, highlighting the possibility that other dangerous pathogens transmitted by the snail where it is native could arrive later or already be present in the United States. The common presence of the human-infecting fishborne trematodes at fishing localities, the widespread popularity of eating uncooked fish (eg, as sashimi, sushi, poke, or ceviche), and the potential for additional human-infecting trematodes to also be introduced, all justify consideration of the introduced snail and its parasites from a public health perspective in California and other areas in the United States where the parasites or the host snail have already been reported.


Assuntos
Parasitos , Trematódeos , Infecções por Trematódeos , Animais , Humanos , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia , Caramujos/parasitologia , California/epidemiologia
8.
Trends Biochem Sci ; 44(4): 365-379, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30651181

RESUMO

Toxins are substances produced from biological sources (e.g., animal, plants, microorganisms) that have deleterious effects on a living organism. Despite the obvious health concerns of being exposed to toxins, they are having substantial positive impacts in a number of industrial sectors. Several toxin-derived products are approved for clinical, veterinary, or agrochemical uses. This review sets out the case for toxins as 'friends' that are providing the basis of novel medicines, insecticides, and even nucleic acid sequencing technologies. We also discuss emerging toxins ('foes') that are becoming increasingly prevalent in a range of contexts through climate change and the globalisation of food supply chains and that ultimately pose a risk to health.


Assuntos
Toxinas Biológicas/efeitos adversos , Toxinas Biológicas/uso terapêutico , Animais , Humanos , Toxinas Biológicas/química
9.
J Am Chem Soc ; 145(28): 15443-15455, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37405391

RESUMO

Molecular beam experiments together with electronic structure calculations provide the first evidence of a complex network of elementary gas-phase reactions culminating in the bottom-up preparation of the 24π aromatic coronene (C24H12) molecule─a representative peri-fused polycyclic aromatic hydrocarbon (PAH) central to the complex chemistry of combustion systems and circumstellar envelopes of carbon stars. The gas-phase synthesis of coronene proceeds via aryl radical-mediated ring annulations through benzo[e]pyrene (C20H12) and benzo[ghi]perylene (C22H12) involving armchair-, zigzag-, and arm-zig-edged aromatic intermediates, highlighting the chemical diversity of molecular mass growth processes to polycyclic aromatic hydrocarbons. The isomer-selective identification of five- to six-ringed aromatics culminating with the detection of coronene is accomplished through photoionization and is based upon photoionization efficiency curves along with photoion mass-selected threshold photoelectron spectra, providing a versatile concept of molecular mass growth processes via aromatic and resonantly stabilized free radical intermediates to two-dimensional carbonaceous nanostructures.

10.
Clin Exp Allergy ; 53(9): 930-940, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37437951

RESUMO

BACKGROUND: Indoor dust (ID) is a source of peanut proteins and immunostimulatory adjuvants (e.g. LPS) that can promote airway sensitization to peanut. We aimed to determine whether a single airway exposure to peanut plus adjuvant is sufficient to prevent oral tolerance. METHODS: To determine the effect of a single priming event, C57BL/6J mice were exposed once to peanut plus adjuvant through the airway, followed by either airway or low-dose oral exposure to peanut, and assessed for peanut allergy. Oral tolerance was investigated by feeding high-dose peanut followed by airway sensitization. To determine whether a single priming could prevent oral tolerance, the high-dose peanut regimen was applied after a single airway exposure to peanut plus adjuvant. Peanut-specific IgE and IgG1 were quantified, and mice were challenged to peanut to assess allergy. Peanut-specific CD4+ memory T cells (CD4+ TCRß+ CD44hi CD154+ ) were quantified in mediastinal lymph nodes following airway priming. RESULTS: Mice co-exposed to peanut with LPS or ID through the airway were primed to develop peanut allergy after subsequent low-dose oral or airway exposures to peanut. Oral tolerance was induced in mice fed high-dose peanut prior to airway sensitization. In contrast, mice fed high-dose peanut following a single airway exposure to peanut plus adjuvant led to allergy. Peanut-specific CD4+ memory T cells were detected as early as 7 days after the single airway priming with peanut plus adjuvant, however, delaying peanut feeding even 1 day following priming led to allergy, whereas peanut feeding the same day as priming led to tolerance. CONCLUSIONS: A single airway exposure to peanut plus adjuvant is sufficient to prime the immune system to develop allergy following subsequent high-dose oral exposure. These results highlight the importance of introducing peanut as early as possible to prevent sensitization through a non-oral priming event.


Assuntos
Arachis , Hipersensibilidade a Amendoim , Camundongos , Animais , Citocinas/metabolismo , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Adjuvantes Imunológicos , Poeira , Tolerância Imunológica , Alérgenos
11.
Chemphyschem ; 24(4): e202200660, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36283955

RESUMO

We report the formation of the cyclic methylphosphonic acid trimer [c-(CH3 PO2 )3 ] through condensation reactions during thermal processing of low-temperature methylphosphonic acid samples exploiting photoionization reflectron time-of-flight mass spectrometry (PI-ReTOF-MS) along with electronic structure calculations. Cyclic methylphosphonic acid trimers are formed in the solid state and detected together with its protonated species in the gas phase upon single photon ionization. Our studies provide an understanding of the preparation of phosphorus-bearing potentially prebiotic molecules and the fundamental knowledge of low-temperature phosphorus chemistry in extraterrestrial environments.

12.
Curr Allergy Asthma Rep ; 23(8): 427-433, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37227666

RESUMO

PURPOSE OF REVIEW: Many factors have been reported to contribute to the development of food allergy. Here, we summarize the role of environmental exposure to foods as a major risk factor for developing food allergy. RECENT FINDINGS: Peanut proteins are detectable and biologically active in household environments, where infants spend a majority of their time, providing an environmental source of allergen exposure. Recent evidence from clinical studies and mouse models suggests both the airway and skin are routes of exposure that lead to peanut sensitization. Environmental exposure to peanut has been clearly associated with the development of peanut allergy, although other factors such as genetic predisposition, microbial exposures, and timing of oral feeding of allergens also likely contribute. Future studies should more comprehensively assess the contributions of each of these factors for a variety of food allergens to provide more clear targets for prevention of food allergy.


Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Amendoim , Humanos , Animais , Camundongos , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/etiologia , Hipersensibilidade Alimentar/prevenção & controle , Alimentos , Fatores de Risco , Hipersensibilidade a Amendoim/etiologia , Hipersensibilidade a Amendoim/prevenção & controle , Exposição Ambiental/efeitos adversos , Arachis/efeitos adversos
13.
Phys Chem Chem Phys ; 25(2): 936-953, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36285574

RESUMO

We unravel, for the very first time, the formation pathways of hydroxyacetone (CH3COCH2OH), methyl acetate (CH3COOCH3), and 3-hydroxypropanal (HCOCH2CH2OH), as well as their enol tautomers within mixed ices of methanol (CH3OH) and acetaldehyde (CH3CHO) analogous to interstellar ices in the ISM exposed to ionizing radiation at ultralow temperatures of 5 K. Exploiting photoionization reflectron time-of-flight mass spectrometry (PI-ReToF-MS) and isotopically labeled ices, the reaction products were selectively photoionized allowing for isomer discrimination during the temperature-programmed desorption phase. Based on the distinct mass-to-charge ratios and ionization energies of the identified species, we reveal the formation pathways of hydroxyacetone (CH3COCH2OH), methyl acetate (CH3COOCH3), and 3-hydroxypropanal (HCOCH2CH2OH) via radical-radical recombination reactions and of their enol tautomers (prop-1-ene-1,2-diol (CH3C(OH)CHOH), prop-2-ene-1,2-diol (CH2C(OH)CH2OH), 1-methoxyethen-1-ol (CH3OC(OH)CH2) and prop-1-ene-1,3-diol (HOCH2CHCHOH)) via keto-enol tautomerization. To the best of our knowledge, 1-methoxyethen-1-ol (CH3OC(OH)CH2) and prop-1-ene-1,3-diol (HOCH2CHCHOH) are experimentally identified for the first time. Our findings help to constrain the formation mechanism of hydroxyacetone and methyl acetate detected within star-forming regions and suggest that the hitherto astronomically unobserved isomer 3-hydroxypropanal and its enol tautomers represent promising candidates for future astronomical searches. These enol tautomers may contribute to the molecular synthesis of biologically relevant molecules in deep space due to their nucleophilic character and high reactivity.


Assuntos
Acetatos , Acetona , Isomerismo
14.
Br J Anaesth ; 131(4): 632-633, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37718091

RESUMO

The subjective experiences of sedation or anaesthesia are underexplored. A recent study by Valli and colleagues (Br J Anaesth 2023; 131: 348-59) found similar frequency and content of recalled experiences after both non-rapid eye movement sleep and target-controlled infusions of propofol or dexmedetomidine titrated to verbal unresponsiveness. The authors find that the phenomenological similarities between consciousness during sleep and sedation mirror their physiological similarities. Intriguingly, in this small sample, conscious experience did not show a dose-dependent response suggesting other factors are important in determining the propensity for consciousness under sedation.


Assuntos
Anestesia , Anestesiologia , Humanos , Estado de Consciência , Sono , Sedação Consciente
15.
J Phys Chem A ; 127(37): 7707-7717, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37682229

RESUMO

FOX-7 (1,1-diamino-2,2-dinitroethylene) was photolyzed with 202 nm photons to probe reaction energies, leading to the decomposition of this energetic material and to compare results from irradiations using lower-energy 532 and 355 nm photons as well as higher-energy electrons. The photolysis occurred at 5 K to suppress thermal reactions, and the solid samples were monitored using Fourier transform infrared spectroscopy (FTIR), which observed carbon dioxide (CO2), carbon monoxide (CO), cyanide (CN-), and cyanate (OCN-) after irradiation. During warming to 300 K, subliming products were detected using electron-impact quadrupole mass spectrometry (EI-QMS) and photoionization time-of-flight mass spectrometry (PI-ReTOF-MS). Five products were observed in QMS: water (H2O), carbon monoxide (CO), nitric oxide (NO), carbon dioxide (CO2), and cyanogen (NCCN). The ReTOF-MS results showed overlap with electron irradiation products but also included three intermediates for the oxidation of ammonia and nitric oxide: hydroxylamine (NH2OH), nitrosamine (NH2NO), and the largest product at 76 amu with the proposed assignment of hydroxyurea (NH2C(O)NHOH). These results highlight the role of reactive oxygen intermediates and nitro-to-nitrite isomerization as key early reactions that lead to a diverse array of decomposition products.

16.
J Phys Chem A ; 127(15): 3390-3401, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37027514

RESUMO

Solid FOX-7 (1,1-diamino-2,2-dinitroethylene), an energetic material of interest due to its high stability and low shock/thermal sensitivity, was exposed to energetic electrons at 5 K to explore the fundamental mechanisms leading to decomposition products and provide a better understanding of the reaction pathways involved. As a result of the radiation exposure, infrared spectroscopy revealed carbon dioxide (CO2) and carbon monoxide (CO) trapped in the FOX-7 matrix, while these compounds along with water (H2O), nitrogen monoxide (NO), and cyanogen (C2N2) were detected exploiting quadrupole mass spectrometry both during irradiation and during the warming phase from 5 to 300 K. Photoionization reflectron time-of-flight mass spectrometry detected small molecules such as ammonia (NH3), nitrogen monoxide (NO), and nitrogen dioxide (NO2) as well as more complex molecules up to 96 amu. Potential reaction pathways are presented and assignments are discussed. Among the reaction mechanisms, the importance of an initial nitro-to-nitrite isomerization is highlighted by the observed decomposition products.

17.
J Public Health (Oxf) ; 45(3): 654-662, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37147914

RESUMO

BACKGROUND: Exposure to poor air quality is one of the most significant environmental public health challenges. In the UK, local authorities (LAs) are responsible for monitoring and managing air quality. This article explores the need and mechanisms for cross-departmental working in LAs to make decisions about air quality issues. METHODS: Semi-structured qualitative interviews with public health, environmental health and transport staff from LAs within the Southwest of UK. Interviews were conducted between April and August 2021 and analysed using a thematic approach. RESULTS: In sum, 24 staff from 7 LAs participated. Local authority staff in public health, environmental health and transport teams recognized that managing air quality was a cross-departmental issue. To enable effective integrated working staff described four successful mechanisms: (i) policy commitments and political support; (ii) dedicated air quality steering groups; (iii) existing governance and oversight groups; and (iv) networking and relationships. CONCLUSIONS: This study has identified mechanisms that LA staff have found support cross-departmental and integrated working on air quality issues. These are mechanisms that have helped environmental health staff work towards achieving compliance with pollution limits, and that have helped public health staff get air quality considerations recognized as a wider health issue.


Assuntos
Poluição do Ar , Humanos , Inglaterra , Pesquisa Qualitativa , Poluição do Ar/prevenção & controle , Saúde Ambiental , Saúde Pública
18.
Mar Drugs ; 21(4)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37103383

RESUMO

Tropical epibenthic dinoflagellate communities produce a plethora of bioactive secondary metabolites, including the toxins ciguatoxins (CTXs) and potentially gambierones, that can contaminate fishes, leading to ciguatera poisoning (CP) when consumed by humans. Many studies have assessed the cellular toxicity of causative dinoflagellate species to better understand the dynamics of CP outbreaks. However, few studies have explored extracellular toxin pools which may also enter the food web, including through alternative and unanticipated routes of exposure. Additionally, the extracellular exhibition of toxins would suggest an ecological function and may prove important to the ecology of the CP-associated dinoflagellate species. In this study, semi-purified extracts obtained from the media of a Coolia palmyrensis strain (DISL57) isolated from the U.S. Virgin Islands were assessed for bioactivity via a sodium channel specific mouse neuroblastoma cell viability assay and associated metabolites evaluated by targeted and non-targeted liquid chromatography tandem and high-resolution mass spectrometry. We found that extracts of C. palmyrensis media exhibit both veratrine enhancing bioactivity and non-specific bioactivity. LC-HR-MS analysis of the same extract fractions identified gambierone and multiple undescribed peaks with mass spectral characteristics suggestive of structural similarities to polyether compounds. These findings implicate C. palmyrensis as a potential contributor to CP and highlight extracellular toxin pools as a potentially significant source of toxins that may enter the food web through multiple exposure pathways.


Assuntos
Ciguatera , Ciguatoxinas , Dinoflagellida , Toxinas Biológicas , Animais , Camundongos , Humanos , Dinoflagellida/química , Ciguatoxinas/toxicidade
19.
J Med Internet Res ; 25: e43496, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36811939

RESUMO

BACKGROUND: In 2022, NHS England announced plans to ensure that all adult primary care patients in England would have full online access to new data added to their general practitioner (GP) record. However, this plan has not yet been fully implemented. Since April 2020, the GP contract in England has already committed to offering patients full online record access on a prospective basis and on request. However, there has been limited research into UK GPs' experiences and opinions about this practice innovation. OBJECTIVE: This study aimed to explore the experiences and opinions of GPs in England about patients' access to their full web-based health record, including clinicians' free-text summaries of the consultation (so-called "open notes"). METHODS: In March 2022, using a convenience sample, we administered a web-based mixed methods survey of 400 GPs in the United Kingdom to explore their experiences and opinions about the impact on patients and GPs' practices to offer patients full online access to their health records. Participants were recruited using the clinician marketing service Doctors.net.uk from registered GPs currently working in England. We conducted a qualitative descriptive analysis of written responses ("comments") to 4 open-ended questions embedded in a web-based questionnaire. RESULTS: Of 400 GPs, 224 (56%) left comments that were classified into 4 major themes: increased strain on GP practices, the potential to harm patients, changes to documentation, and legal concerns. GPs believed that patient access would lead to extra work for them, reduced efficiency, and increased burnout. The participants also believed that access would increase patient anxiety and incur risks to patient safety. Experienced and perceived documentation changes included reduced candor and changes to record functionality. Anticipated legal concerns encompassed fears about increased litigation risks and lack of legal guidance to GPs about how to manage documentation that would be read by patients and potential third parties. CONCLUSIONS: This study provides timely information on the views of GPs in England regarding patient access to their web-based health records. Overwhelmingly, GPs were skeptical about the benefits of access both for patients and to their practices. These views are similar to those expressed by clinicians in other countries, including Nordic countries and the United States before patient access. The survey was limited by the convenience sample, and it is not possible to infer that our sample was representative of the opinions of GPs in England. More extensive, qualitative research is required to understand the perspectives of patients in England after experiencing access to their web-based records. Finally, further research is needed to explore objective measures of the impact of patient access to their records on health outcomes, clinician workload, and changes to documentation.


Assuntos
Clínicos Gerais , Adulto , Humanos , Estudos Prospectivos , Atitude do Pessoal de Saúde , Pesquisa Qualitativa , Inquéritos e Questionários , Atenção Primária à Saúde
20.
Environ Monit Assess ; 195(12): 1413, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37924359

RESUMO

Little information exists on the fate and impacts of boats constructed of fibreglass reinforced plastic (FRP) once they reach their end-of-life. In this study, the number of abandoned fishing boats constructed of FRP or constructed of plywood-wood and sheathed by FRP has been determined along the coast of Kerala, India, and chemical emissions have been estimated when boats are burned as a means of disposal. A total of 292 abandoned boats were observed across eight coastal transects constructed around selected landing centres, with abandonment ranging from 13 to 48 per km (average = 29 km-1). This results in the generation of 1420 kg of FRP debris (glass mat and epoxy resin) per km of coastline. A controlled combustion experiment, simulating open burning, revealed that 63% of original boat mass is emitted to the atmosphere, with the remainder forming a burnt residue. Total concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans emitted and remaining were found to be 2.6 ng Nm-3 and 249.6 µg kg-1, respectively, with respective calculated toxicity equivalence (TEQ) levels of 437.6 pg TEQ Nm-3 in air emissions and 26.6 µg TEQ kg-1 in the residue. These figures are equivalent to the total emission from FRP boat burning of about 17,000 µg TEQ t-1. Burning also generates significant quantities of potentially toxic metals, with resulting concentrations of Co, Cr and Cu close to or exceeding soil guideline values. The study calls for a greater awareness of the impacts arising from boat abandonment and burning amongst fishermen, and guidelines or regulatory protocols regarding safe and sustainable boat disposal or recycling.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Incineração , Navios , Caça , Monitoramento Ambiental , Dibenzofuranos Policlorados/análise
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