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1.
Proc Natl Acad Sci U S A ; 120(49): e2305763120, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38015845

RESUMEN

Marine dissolved organic nitrogen (DON) is one of the planet's largest reservoirs of fixed N, which persists even in the N-limited oligotrophic surface ocean. The vast majority of the ocean's total DON reservoir is refractory (RDON), primarily composed of low molecular weight (LMW) compounds in the subsurface and deep sea. However, the composition of this major N pool, as well as the reasons for its accumulation and persistence, are not understood. Past characterization of the analytically more tractable, but quantitatively minor, high molecular weight (HMW) DON fraction revealed a functionally simple amide-dominated composition. While extensive work in the past two decades has revealed enormous complexity and structural diversity in LMW dissolved organic carbon, no efforts have specifically targeted LMW nitrogenous molecules. Here, we report the first coupled isotopic and solid-state NMR structural analysis of LMW DON isolated throughout the water column in two ocean basins. Together these results provide a first view into the composition, potential sources, and cycling of this dominant portion of marine DON. Our data indicate that RDON is dominated by 15N-depleted heterocyclic-N structures, entirely distinct from previously characterized HMW material. This fundamentally new view of marine DON composition suggests an important structural control for RDON accumulation and persistence in the ocean. The mechanisms of production, cycling, and removal of these heterocyclic-N-containing compounds now represents a central challenge in our understanding of the ocean's DON reservoir.

2.
J Neurosci ; 42(32): 6186-6194, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35794014

RESUMEN

Midbrain dopamine neurons play central physiological roles in voluntary movement, reward learning, and motivated behavior. Inhibitory signaling at somatodendritic dopamine D2 receptor (D2R) synapses modulates excitability of dopamine neurons. The neuropeptide neurotensin is expressed by many inputs to the midbrain and induces LTD of D2R synaptic currents (LTDDA); however, the source of neurotensin that is responsible for LTDDA is not known. Here we show, in brain slices from male and female mice, that LTDDA is driven by neurotensin released by dopamine neurons themselves. Optogenetic stimulation of dopamine neurons was sufficient to induce LTDDA in the substantia nigra, but not the VTA, and was dependent on neurotensin receptor signaling, postsynaptic calcium, and vacuolar-type H+-ATPase activity in the postsynaptic cell. These findings reveal a novel form of signaling between dopamine neurons involving release of the peptide neurotensin, which may act as a feedforward mechanism to increase dopamine neuron excitability.SIGNIFICANCE STATEMENT Dopamine neurons in the midbrain play a critical role in reward learning and the initiation of movement. Aberrant dopamine neuron function is implicated in a range of diseases and disorders, including Parkinson's disease, schizophrenia, obesity, and substance use disorders. D2 receptor-mediated PSCs are produced by a rare form of dendrodendritic synaptic transmission between dopamine neurons. These D2 receptor-mediated PSCs undergo LTD following application of the neuropeptide neurotensin. Here we show that release of neurotensin by dopamine neurons themselves is sufficient to induce LTD of dopamine transmission in the substantia nigra. Neurotensin signaling therefore mediates a second form of interdopamine neuron communication and may provide a mechanism by which dopamine neurons maintain excitability when nigral dopamine is elevated.


Asunto(s)
Neuronas Dopaminérgicas , Neurotensina/metabolismo , Sustancia Negra/metabolismo , Animales , Dopamina , Neuronas Dopaminérgicas/metabolismo , Femenino , Masculino , Ratones , Neuropéptidos/metabolismo
3.
Small ; 19(6): e2205487, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36470595

RESUMEN

Metal boride nanostructures have shown significant promise for hydrogen storage applications. However, the synthesis of nanoscale metal boride particles is challenging because of their high surface energy, strong inter- and intraplanar bonding, and difficult-to-control surface termination. Here, it is demonstrated that mechanochemical exfoliation of magnesium diboride in zirconia produces 3-4 nm ultrathin MgB2 nanosheets (multilayers) in high yield. High-pressure hydrogenation of these multilayers at 70 MPa and 330 °C followed by dehydrogenation at 390 °C reveals a hydrogen capacity of 5.1 wt%, which is ≈50 times larger than the capacity of bulk MgB2 under the same conditions. This enhancement is attributed to the creation of defective sites by ball-milling and incomplete Mg surface coverage in MgB2 multilayers, which disrupts the stable boron-boron ring structure. The density functional theory calculations indicate that the balance of Mg on the MgB2 nanosheet surface changes as the material hydrogenates, as it is energetically favorable to trade a small number of Mg vacancies in Mg(BH4 )2 for greater Mg coverage on the MgB2 surface. The exfoliation and creation of ultrathin layers is a promising new direction for 2D metal boride/borohydride research with the potential to achieve high-capacity reversible hydrogen storage at more moderate pressures and temperatures.

4.
Phys Rev Lett ; 130(22): 222501, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37327448

RESUMEN

The ß-delayed proton decay of ^{13}O has previously been studied, but the direct observation of ß-delayed 3αp decay has not been reported. Rare 3αp events from the decay of excited states in ^{13}N^{⋆} provide a sensitive probe of cluster configurations in ^{13}N. To measure the low-energy products following ß-delayed 3αp decay, the Texas Active Target (TexAT) time projection chamber was employed using the one-at-a-time ß-delayed charged-particle spectroscopy technique at the Cyclotron Institute, Texas A&M University. A total of 1.9×10^{5} ^{13}O implantations were made inside the TexAT time projection chamber. A total of 149 3αp events were observed, yielding a ß-delayed 3αp branching ratio of 0.078(6)%. Four previously unknown α-decaying excited states were observed in ^{13}N at 11.3, 12.4, 13.1, and 13.7 MeV decaying via the 3α+p channel.


Asunto(s)
Protones , Humanos , Análisis Espectral
5.
Inorg Chem ; 62(16): 6242-6254, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-36580490

RESUMEN

Deciphering the solution chemistry and speciation of actinides is inherently difficult due to radioactivity, rarity, and cost constraints, especially for transplutonium elements. In this context, the development of new chelating platforms for actinides and associated spectroscopic techniques is particularly important. In this study, we investigate a relatively overlooked class of chelators for actinide binding, namely, polyoxometalates (POMs). We provide the first NMR measurements on americium-POM and curium-POM complexes, using one-dimensional (1D) 31P NMR, variable-temperature NMR, and spin-lattice relaxation time (T1) experiments. The proposed POM-NMR approach allows for the study of trivalent f-elements even when only microgram amounts are available and in phosphate-containing solutions where f-elements are typically insoluble. The solution-state speciation of trivalent americium, curium, plus multiple lanthanide ions (La3+, Nd3+, Sm3+, Eu3+, Yb3+, and Lu3+), in the presence of the model POM ligand PW11O397- was elucidated and revealed the concurrent formation of two stable complexes, [MIII(PW11O39)(H2O)x]4- and [MIII(PW11O39)2]11-. Interconversion reaction constants, reaction enthalpies, and reaction entropies were derived from the NMR data. The NMR results also provide experimental evidence of the weakly paramagnetic nature of the Am3+ and Cm3+ ions in solution. Furthermore, the study reveals a previously unnoticed periodicity break along the f-element series with the reversal of T1 relaxation times of the 1:1 and 1:2 complexes and the preferential formation of the long T1 species for the early lanthanides versus the short T1 species for the late lanthanides, americium, and curium. Given the broad variety of POM ligands that exist, with many of them containing NMR-active nuclei, the combined POM-NMR approach reported here opens a new avenue to investigate difficult-to-study elements such as heavy actinides and other radionuclides.

6.
Inorg Chem ; 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37851526

RESUMEN

Gallium trichloride (GaCl3) was used as a solvent for the oxidative dissolution of the lanthanide (Ln) metals cerium (Ce) and holmium (Ho). Reactions were performed at temperatures above 100 °C in sealed vessels to maintain the liquid phase for GaCl3 during the oxidizing reactions. The best results were obtained from reactions using 8 equiv of GaCl3 to metal where the inorganic complexes [Ga][Ln(GaCl4)4] [Ln = Ce (1), Ho (2)] could be isolated. Recrystallization of 1 and 2 employing fluorobenzene (C6H5F) produced [Ga(η6-C6H5F)2][Ln(GaCl4)4] [Ln = Ce (3), Ho (4)] where reversible η6 coordination of C6H5F to [Ga]+ was observed. All complexes were characterized through elemental analysis (F and Cl), IR and UV-vis-near-IR spectroscopies, and both solution and solid-state NMR techniques.

7.
Occup Environ Med ; 79(7): 486-493, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35027440

RESUMEN

OBJECTIVES: To investigate the rates of return to work and workability among working-age people following total hip arthroplasty (THA). METHODS: Participants from the Geneva Arthroplasty Registry and the Clinical Outcomes for Arthroplasty Study aged 18-64 years when they had primary THA and with at least 5 years' follow-up were mailed a questionnaire 2017-2019. Information was collected about preoperative and post-THA employment along with exposure to physically demanding activities at work or in leisure. Patterns of change of job were explored. Survival analyses using Cox proportional hazard models were created to explore risk factors for having to stop work because of difficulties with the replaced hip. RESULTS: In total, 825 returned a questionnaire (response 58%), 392 (48%) men, mean age 58 years, median follow-up 7.5 years post-THA. The majority (93%) of those who worked preoperatively returned to work, mostly in the same sector but higher rates of non-return (36%-41%) were seen among process, plant and machine operatives and workers in elementary occupations. 7% reported subsequently leaving work because of their replaced hip and the risk of this was strongly associated with: standing >4 hours/day (HR 3.81, 95% CI 1.62 to 8.96); kneeling/squatting (HR 3.32, 95% CI 1.46 to 7.55) and/or carrying/lifting ≥10 kg (HR 5.43, 95% CI 2.29 to 12.88). CONCLUSIONS: It may be more difficult to return to some (particularly physically demanding) jobs post-THA than others. Rehabilitation may need to be targeted to these types of workers or it may be that redeployment or job change counselling are required.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Artroplastia de Reemplazo de Cadera/rehabilitación , Artroplastia de Reemplazo de Rodilla/rehabilitación , Empleo , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ocupaciones
8.
Addict Biol ; 27(2): e13120, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34825430

RESUMEN

Dopamine neurons in the substantia nigra (SN) and ventral tegmental area (VTA) play a central role in the reinforcing properties of abused drugs including methamphetamine and cocaine. Chronic effects of psychostimulants in the SN/VTA also involve non-dopaminergic transmitters, including glutamate and the stress-related peptide corticotropin-releasing factor (CRF). In the SN/VTA, astrocytes express a variety of membrane-bound neurotransmitter receptors and transporters that influence neurotransmission. CRF receptor type 2 (CRF2) activity in the VTA is important for stress-induced relapse and drug-seeking behaviour, but the localization of its effects is incompletely understood. Here, we first identified CRF2 transcript in astrocytes of the SN/VTA using RNA-Seq in Aldh1l1;NuTRAP mice and confirmed it using in situ hybridization (RNAscope) in wild-type mice. We then used immunofluorescence to quantify the astrocytic marker protein S100ß, glial-specific glutamate/aspartate transporter GLAST, and CRF2 in the SN/VTA following 12 days of treatment (i.p.) with methamphetamine (3 mg/kg), cocaine (10 mg/kg), or saline. We observed a significant decrease in GLAST immunofluorescence in brains of psychostimulant treated mice compared with saline controls. In addition, we observed increased labelling of CRF2 in drug treated groups, a decrease in the number of S100ß positive cells, and an increase of co-staining of CRF2 with both S100ß and tyrosine hydroxylase (dopamine neurons). Our results suggest a significant interaction between CRF2, GLAST, and astrocytes in the midbrain that emerges with repeated exposure to psychostimulants. These findings provide rationale for future investigation of astrocyte-based strategies for altering cellular and circuit function in response to stress and drug exposure.


Asunto(s)
Sistema de Transporte de Aminoácidos X-AG/metabolismo , Cocaína , Hormona Liberadora de Corticotropina/metabolismo , Metanfetamina , Área Tegmental Ventral , Animales , Astrocitos/metabolismo , Cocaína/farmacología , Metanfetamina/farmacología , Ratones , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/metabolismo
9.
BMC Public Health ; 22(1): 116, 2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-35039031

RESUMEN

BACKGROUND: Lower birth rates and increasing longevity have resulted in ageing populations in European countries. These demographic changes place challenges on pension provision as numbers of those who are economically inactive and retired increase relative to those in paid work. Therefore, governments need workers to postpone retirement and work to older ages. Whilst health and wealth are important in retirement decision-making, considerably less is known about the effects of workplace factors. The aim of this study was to explore the views of recent UK retirees about the role that work-related factors played in their decision to retire. METHODS: This qualitative study was nested within the Health and Employment After Fifty (HEAF) cohort. People who had retired 3-6 years previously (not for health reasons) were purposively sampled to obtain the views of men and women from a range of socio-economic backgrounds and jobs. Semi-structured interviews were carried out by telephone using a pre-defined topic guide. Interviews were audio-recorded, transcribed and analysed thematically. RESULTS: Seventeen interviews were conducted. Thematic analysis showed that retirement decisions were complex and multi-factorial but that work-related factors contributed to decision-making in two main ways. First, some work factors pushed participants towards retirement. These were perceptions that: workplace change had affected the way they were valued or increased pressure on them; work demands, including commuting, had intruded excessively on personal time, effects that were exacerbated by modern technology; work was draining, isolating or under-appreciated; and /or that work was causing physical strain or discomfort relative to their perception of their capacity. In contrast, work factors could also cause participants to pull back towards work, particularly: autonomy; supportive work colleagues; a sense of being appreciated; and perceived job flexibility. CONCLUSIONS: Recent retirees explained that their decision to retire was multi-factorial but work-related factors contributed importantly. Potentially, employers could: review workers' perceptions about their work; their capacity in relation to job demands; increase flexibility; and facilitate a supportive work community to encourage longer working lives.


Asunto(s)
Empleo , Jubilación , Femenino , Humanos , Masculino , Ocupaciones , Pensiones , Reino Unido
10.
Occup Med (Lond) ; 72(2): 132-141, 2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-34927206

RESUMEN

BACKGROUND: UK Biobank (UKB) is a large prospective cohort capturing numerous health outcomes, but limited occupational information (job title, self-reported manual work and occupational walking/standing). AIMS: To create and evaluate validity of a linkage between UKB and a job exposure matrix for physical work exposures based on the US Occupational Information Network (O*NET) database. METHODS: Job titles and UK Standard Occupational Classification (SOC) codes were collected during UKB baseline assessment visits. Using existing crosswalks, UK SOC codes were mapped to US SOC codes allowing linkage to O*NET variables capturing numerous dimensions of physical work. Job titles with the highest O*NET scores were assessed to evaluate face validity. Spearman's correlation coefficients were calculated to compare O*NET scores to self-reported UKB measures. RESULTS: Among 324 114 participants reporting job titles, 323 936 were linked to O*NET. Expected relationships between scores and self-reported measures were observed. For static strength (0-7 scale), the median O*NET score was 1.0 (e.g. audiologists), with a highest score of 4.88 for stone masons and a positive correlation with self-reported heavy manual work (Spearman's coefficient = 0.50). For time spent standing (1-5 scale), the median O*NET score was 2.72 with a highest score of 5 for cooks and a positive correlation with self-reported occupational walking/standing (Spearman's coefficient = 0.56). CONCLUSIONS: While most jobs were not physically demanding, a wide range of physical work values were assigned to a diverse set of jobs. This novel linkage of a job exposure matrix to UKB provides a potentially valuable tool for understanding relationships between occupational exposures and disease.


Asunto(s)
Bancos de Muestras Biológicas , Exposición Profesional , Humanos , Exposición Profesional/efectos adversos , Ocupaciones , Estudios Prospectivos , Reino Unido/epidemiología
11.
Environ Sci Technol ; 55(3): 1626-1636, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33471994

RESUMEN

Uranium contamination of soils and groundwater in the United States represents a significant health risk and will require multiple remediation approaches. Microbial phosphatase activity coupled to the addition of an organic P source has recently been studied as a remediation strategy that provides an extended release of inorganic P (Pi) into U-contaminated sites, resulting in the precipitation of meta-autunite minerals. Previous laboratory- and field-based biomineralization studies have investigated environments with relatively high U concentrations (>20 µM). However, most contaminated sites have much lower U concentrations (<2 µM). The Environmental Protection Agency (EPA) limit for U in drinking water is 0.126 µM. Reaching this regulatory limit becomes challenging as U concentrations approach autunite solubility. We studied the precipitation of U(VI)-phosphate minerals by an environmental isolate of Caulobacter sp. (strain OR37) from an Oak Ridge, Tennessee, U-contaminated site. Abiotic U(VI) solubility experiments reveal that U(VI)-phosphate minerals do not form in the presence of excess Pi (500 µM) when U(VI) concentrations are <1 µM and pH is <5. When OR37 cells are reacted under the same conditions with Pi or glycerol-2-phosphate, U(VI)-phosphate mineral formation was observed, along with the formation of intracellular polyphosphate granules. These results show that bacteria provide supersaturated microenvironments needed for U(VI)-phosphate mineralization while hydrolyzing organic P sources. This provides a pathway to lower U concentrations to below EPA limits for drinking water.


Asunto(s)
Caulobacter , Uranio , Biomineralización , Concentración de Iones de Hidrógeno , Fosfatos , Tennessee , Uranio/análisis
12.
Occup Environ Med ; 78(1): 36-42, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32917741

RESUMEN

OBJECTIVES: Health and job satisfaction are key independent determinants of ability to work to older ages. We investigated the interaction of these two important factors on health-related job loss (HRJL) over 2 years of follow-up comparing male and female older workers. METHODS: A population sample of adults aged 50-64 years, recruited from 24 English general practices in the Health and Employment After Fifty (HEAF) study, completed questionnaires at baseline with follow-ups at 12 and 24 months. Multiple-record Cox proportional hazards models were performed to explore the main effects of, and potential interactions between, job satisfaction and self-rated health (SRH) as predictors of time to first HRJL. RESULTS: Of the initial 8134 participants, 5143 were ever in work in the study period. Among men, 5.7% and 14.3% reported job dissatisfaction (those in good and poor SRH, respectively), while among women these percentages were 4.6 and 12.9. HRJL was reported by 106 men and 176 women. Men in good health dissatisfied with their job had a sixfold (HR=6.4; 95% CI 3.3 to 12.4) increased risk of HRJL compared with men satisfied with their job (significant multiplicative interaction). Women dissatisfied with their job were more likely to have an HRJL within 2 years of follow-up irrespective of their SRH. CONCLUSIONS: SRH and job dissatisfaction have important individual effects on the risk of stopping work for health among older workers. These findings point to the importance of job satisfaction in reducing health-related exit from paid work among older workers.


Asunto(s)
Empleo/estadística & datos numéricos , Estado de Salud , Satisfacción en el Trabajo , Envejecimiento , Inglaterra , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios
13.
Vascular ; 29(4): 567-573, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33054678

RESUMEN

OBJECTIVES: Paclitaxel-eluting stents have demonstrated improved patency over balloon angioplasty and bare metal stenting for endovascular interventions in the femoral-popliteal segment. Recently, concerns have arisen regarding the safety of paclitaxel use and its association with mortality. This study aims to examine real-world, long-term mortality, and patency of patients treated with the Zilver PTX drug-eluting stent. METHODS: Patients treated with the PTX stent after FDA approval between 2013 and 2015 were identified from an institutional database. Demographic, procedural, and device information was collected and initial- and lifetime-exposure dose of paclitaxel was calculated. The primary outcome was all-cause mortality and its association with paclitaxel exposure. Long-term patency was also evaluated. RESULTS: Seventy-nine procedures involving PTX placement were performed on 64 individual patients during the study period, with 15 (23.4%) having bilateral procedures. Average age was 70 years, and 71.9% were male. Forty-five patients (70.3%) were claudicants, and 19 (29.7%) had chronic, limb-threatening ischemia. An average of 2.3 PTX stents, totaling 203 mm in length, were placed per procedure. Paclitaxel exposure was 1.87 mg/procedure initially (range 0.38-4.03 mg), and average lifetime exposure was 4.65 mg/patient (range 0.38-27.91 mg). Average follow-up was 59.6 months. Kaplan-Meier estimated survival was 96.9%, 81.2% and 71.7% at one , three, and five years. On multivariate analysis, no specific factors were associated with overall morality including initial paclitaxel dose (HR 0.99, 95% CI 0.99-1.00) and lifetime paclitaxel exposure (HR 0.98, 95% CI 0.89-1.08). Kaplan-Meier primary patency was 76.2%, 60.1%, and 29.3% at one, two, and five years, respectively. Secondary patency was 92.2%, 85.4%, and 75.2% at the same intervals. CONCLUSIONS: At a mean follow-up of five years, exposure to higher doses of paclitaxel from Zilver PTX does not appear to be associated with increased mortality compared to lower doses in real-world patients. Long-term patency rates confirm the efficacy of Zilver PTX, and further investigation may be warranted before abandoning paclitaxel use altogether.


Asunto(s)
Fármacos Cardiovasculares/administración & dosificación , Stents Liberadores de Fármacos , Procedimientos Endovasculares/instrumentación , Arteria Femoral , Paclitaxel/administración & dosificación , Enfermedad Arterial Periférica/terapia , Arteria Poplítea , Anciano , Anciano de 80 o más Años , Fármacos Cardiovasculares/efectos adversos , Bases de Datos Factuales , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Paclitaxel/efectos adversos , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/mortalidad , Enfermedad Arterial Periférica/fisiopatología , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/fisiopatología , Supervivencia sin Progresión , Diseño de Prótesis , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Grado de Desobstrucción Vascular
14.
Angew Chem Int Ed Engl ; 60(49): 25815-25824, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34459093

RESUMEN

The highly unfavorable thermodynamics of direct aluminum hydrogenation can be overcome by stabilizing alane within a nanoporous bipyridine-functionalized covalent triazine framework (AlH3 @CTF-bipyridine). This material and the counterpart AlH3 @CTF-biphenyl rapidly desorb H2 between 95 and 154 °C, with desorption complete at 250 °C. Sieverts measurements, 27 Al MAS NMR and 27 Al{1 H} REDOR experiments, and computational spectroscopy reveal that AlH3 @CTF-bipyridine dehydrogenation is reversible at 60 °C under 700 bar hydrogen, >10 times lower pressure than that required to hydrogenate bulk aluminum. DFT calculations and EPR measurements support an unconventional mechanism whereby strong AlH3 binding to bipyridine results in single-electron transfer to form AlH2 (AlH3 )n clusters. The resulting size-dependent charge redistribution alters the dehydrogenation/rehydrogenation thermochemistry, suggesting a novel strategy to enable reversibility in high-capacity metal hydrides.

15.
Ann Vasc Surg ; 62: 45-50.e2, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31201974

RESUMEN

BACKGROUND: The rates of thromboembolic complications such as deep vein thrombosis (DVT) after venous ablation procedures for symptomatic superficial venous insufficiency are controversial. We sought to describe the risk factors for and incidence of DVT after radiofrequency ablation (RFA) and laser ablation (LA). METHODS: We queried the Truven Health Marketscan Database from 2007-16 for patients who underwent RFA or LA and had a follow-up duplex ultrasound within 30 days of the ablation procedure. The primary outcome was DVT at 7 and 30 days identified by International Classification of Diseases-9 and International Classification of Diseases-10 codes. Multivariable regression was used to evaluate the patient and procedural variables associated with a DVT at 30 days, expressed as odds ratios (ORs) with a 95% confidence interval (95% CI). Patients and procedures with a previous DVT diagnosis were excluded. RESULTS: A total of 256,999 patients underwent 433,286 ablation procedures: 192,195 (44.4%) RFA and 241,091 LA. Of these, 8,203 (1.9%) had a newly diagnosed DVT within 7 days and 13,347 (3.1%) within 30 days of the procedure. The incidence of DVT decreased over the study period. LA (2.8%) demonstrated a lower incidence of DVT at 30 days compared with RFA (3.4%), P < 0.001. On multivariable regression, LA (OR, 0.82; 95% CI 0.80-0.85) was again associated with a decreased risk for 30-day DVT, as was female gender (OR, 0.74; 95% CI, 0.71-0.77), and sclerotherapy performed on the same day (OR, 0.91; 95% CI, 0.85-0.98). A diagnosis of peripheral artery disease (OR, 1.23; 95% CI, 1.16-1.31) and concomitant stab phlebectomy (OR, 1.43; 95% CI, 1.37-1.49) was associated with an increased risk of DVT within 30 days. CONCLUSIONS: The incidence of newly diagnosed DVT within 30 days of an ablation procedure was 3.2%. The risk for DVT decreased in recent years, and LA was associated with an 18% decreased risk compared with RFA.


Asunto(s)
Terapia por Láser/efectos adversos , Extremidad Inferior/irrigación sanguínea , Enfermedad Arterial Periférica/cirugía , Ablación por Radiofrecuencia/efectos adversos , Trombosis de la Vena/etiología , Adulto , Bases de Datos Factuales , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/epidemiología , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología , Trombosis de la Vena/diagnóstico por imagen
16.
Eur J Public Health ; 30(4): 799-806, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32494804

RESUMEN

BACKGROUND: To investigate the prevalence of caregiving and its relationship with work, health and socio-economic circumstances in the Health and Employment After Fifty (HEAF) study. METHODS: The HEAF study comprises 8134 men and women aged 50-64 years recruited from 24 general practices. Socio-demographic, lifestyle and health characteristics and hours per week giving personal care were elicited by postal questionnaire. Objective clinical information about diagnoses/medications was retrieved from health records. Work-related and health risk factors for intense caring responsibilities (≥20 h/week vs. no hours) were explored using logistic regression with adjustment for age and social class. RESULTS: In all, 644 (17%) men and 1153 (26%) women reported caring responsibilities, of whom 93 and 199 were intense caregivers, who were more likely to be socio-economically disadvantaged; less likely to be working and, if combining caring with working (41 men and 90 women), more likely to be part-time/working shifts, than non-carers. Men caring ≥20 h/week were more likely to have COPD and to report musculoskeletal pain, poor/fair self-rated health, depression and sleep problems. Among working women, caring ≥20 h/week was associated with these same health outcomes and also with a doctor-diagnosed mental health problem or musculoskeletal pain in the previous year. CONCLUSIONS: Caregiving is common and unequal in the HEAF cohort, with more high-intensity informal care provided by those with greater levels of socio-economic deprivation, which could affect their employment and health. Caregivers need support to lead long, healthy lives, rather than becoming care needers themselves. Employers and governments need to take caregiving into account and support it actively.


Asunto(s)
Empleo , Mujeres Trabajadoras , Cuidadores , Inglaterra/epidemiología , Femenino , Humanos , Masculino , Clase Social
17.
J Helminthol ; 94: e119, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31959277

RESUMEN

Pseudoacanthocephalus goodmani n. sp. is described from faecal pellets collected from Sclerophrys gutturalis (Power, 1927), the guttural toad. The species is characterized by a suite of characters, including a proboscis armature of 14-18 longitudinal rows of 4-6 hooks with simple roots, lemnisci longer than the proboscis receptacle, equatorial testes, a cluster of elongated cement glands and eggs without polar prolongations of the middle membrane 72.6-85.8 long. The toad had been accidentally translocated from Mauritius to the UK in a tourist's luggage and survived a washing machine cycle. The guttural toad was introduced into Mauritius from South Africa in 1922 and the cane toad, Rhinella marina (Linneaus, 1758), from South America, between 1936 and 1938. It seems most likely, therefore, that P. goodmani was introduced, with the guttural toad, from South Africa. The cane toad is host to the similar species, Pseudoacanthocephalus lutzi, from the Americas, but P. lutzi has not been recorded from places where the cane toad has been introduced elsewhere. Clearly, the guttural toad is a hardy and adaptable species, although it seems unlikely that it could become established in Northern Europe. Nevertheless, any accidental translocation of hosts poses the potential risk of introducing unwanted pathogens into the environment and should be guarded against.


Asunto(s)
Acantocéfalos/clasificación , Bufonidae/parasitología , Acantocéfalos/aislamiento & purificación , Animales , Especies Introducidas , Mauricio
18.
Angew Chem Int Ed Engl ; 59(49): 22185-22193, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32818306

RESUMEN

Lithium phosphorus oxynitride (LiPON) is an amorphous solid-state lithium ion conductor displaying exemplary cyclability against lithium metal anodes. There is no definitive explanation for this stability due to the limited understanding of the structure of LiPON. Herein, we provide a structural model of RF-sputtered LiPON. Information about the short-range structure results from 1D and 2D solid-state NMR experiments. These results are compared with first principles chemical shielding calculations of Li-P-O/N crystals and ab initio molecular dynamics-generated amorphous LiPON models to unequivocally identify the glassy structure as primarily isolated phosphate monomers with N incorporated in both apical and as bridging sites in phosphate dimers. Structural results suggest LiPON's stability is a result of its glassy character. Free-standing LiPON films are produced that exhibit a high degree of flexibility, highlighting the unique mechanical properties of glassy materials.

19.
J Urol ; 202(3): 592-598, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31059668

RESUMEN

PURPOSE: Male lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH) is common in men and can have negative effects on quality of life (QoL). It is the hope that this Guideline becomes a reference for effective evidence-based surgical management of LUTS/BPH. MATERIALS AND METHODS: The evidence team searched Ovid MEDLINE, the Cochrane Library, and the Agency for Healthcare Research and Quality database to identify studies indexed between January 2007-September 2017. Following initial publication, this guideline was amended in 2019 and reflects relevant literature published through January 2019. When sufficient evidence existed, the body of evidence was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. In the absence of sufficient evidence, additional information is provided as Clinical Principles and Expert Opinions (table 1 in supplementary unabridged guideline, https://www.jurology.com). RESULTS: This Guideline provides evidence-based recommendations regarding management of LUTS/BPH utilizing surgery and minimally invasive surgical therapies (MIST). Additional statements are made regarding diagnostic and pre-operative tests. Clinical statements are made in comparison to what is generally accepted as the gold standard (i.e. transurethral resection of the prostate [TURP] monopolar and/or bipolar). This guideline is designed to be used in conjunction with the associated treatment algorithm (see figure).[Figure: see text]Conclusions:The prevalence and the severity of LUTS increases as men age and is an important diagnosis in the healthcare of patients and the welfare of society. This document will undergo updating as knowledge regarding treatments and future surgical options continues to expand.


Asunto(s)
Síntomas del Sistema Urinario Inferior/cirugía , Hiperplasia Prostática/complicaciones , Sociedades Médicas/normas , Procedimientos Quirúrgicos Urológicos Masculinos/normas , Urología/normas , Anciano , Medicina Basada en la Evidencia/métodos , Medicina Basada en la Evidencia/normas , Humanos , Síntomas del Sistema Urinario Inferior/diagnóstico , Síntomas del Sistema Urinario Inferior/etiología , Síntomas del Sistema Urinario Inferior/psicología , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios/métodos , Cuidados Preoperatorios/normas , Próstata/cirugía , Hiperplasia Prostática/cirugía , Calidad de Vida , Estados Unidos , Procedimientos Quirúrgicos Urológicos Masculinos/métodos , Urología/métodos
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