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The objective was to determine the effects of maternal nutrient restriction during gestation on serum microRNA (miRNA) abundance in cattle. Primiparous Angus-cross cows (n=22) were fed either control (CON; to gain 1 Kg/week) or nutrient restricted (NR; 0.55% NEm) diets based on National Research Council requirements. On day 30 of gestation, cows were blocked by body condition and randomly assigned to one of three diets: CON (n=8) days 30-190; NR (n=7) days 30-110 followed by CON days 110-190 (NR/C); or CON (n=7) days 30-110 followed by NR days 110-190 (C/NR). At 190 days of gestation, maternal serum was collected for RNA isolation and analyzed using a miRNA microarray of known Bos taurus sequences. Data were normalized using LOWESS and analyzed via ANOVA. At 190 days of gestation, 16 miRNAs exhibited differential abundance (P<0.05) between treatments. Cows that underwent NR, irrespective of when the insult occurred, had downregulated bta-miR-126-3p compared to CON cows. Bta-miR-16b was downregulated and three miRNAs upregulated in NR/C compared to C/NR and CON cows. Additionally, seven miRNAs were downregulated and four miRNAs upregulated in C/NR compared to NR/C and CON cows. Comparison of NR/C and C/NR cows revealed three differentially abundant (P<0.04) miRNAs (bta-miR-2487_L-2R-3_1ss15CT, bta-miR-215, and bta-miR-760-5p). Top KEGG pathway enrichment of target genes included: pathways in cancer, PI3K-Akt signaling, focal adhesion, Ras signaling, proteoglycans in cancer, and MAPK signaling. In summary, maternal nutrient restriction altered serum miRNA abundance profiles irrespective of the time at which the nutritional insult was induced.
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Doenças dos Bovinos , MicroRNAs , Neoplasias , Feminino , Bovinos , Gravidez , Animais , MicroRNAs/genética , Fosfatidilinositol 3-Quinases , Dieta/veterinária , Nutrientes , Neoplasias/veterináriaRESUMO
BACKGROUND: Equine glandular gastric disease (EGGD) is a common condition of the horse. Misoprostol is reported to be superior to oral omeprazole and sucralfate for treatment. Long-acting intramuscular injectable omeprazole (LAIOMEP) is a novel treatment shown to be effective in a small population. OBJECTIVES: This study aimed to determine LAIOMEP efficacy compared to misoprostol and oral omeprazole and identify characteristics that predict treatment outcome. METHODS: All horses that underwent gastroscopy between 2012 and 2019 were reviewed. Lesions were characterised by 4 blinded observers, all of whom are diplomates in equine internal medicine, using established descriptors from the ECEIM consensus statement and subjective severity. Treatment outcome was ranked as worsened, improved or healed. Consensus lesion type, lesion severity and treatment choice were compared to outcome and data screened using univariate analysis (chi-squared) to determine whether each predicted outcome. Lesion types where univariate analysis predicted a trend (p<0.2) were included in a multiple-regression analysis to identify predictors of outcome irrespective of treatment. RESULTS: Only severity significantly predicted final outcome (p = 0.025) with severe lesions being more likely to improve. Treatment choice did not significantly predict outcome. Overall healing rate was 29% (24 horses), and 43% (44 horses) improved. Treatment healing rates were 23% (10), 12% (7) and 27% (7) for LAIOMEP, misoprostol and oral omeprazole, respectively, with improvement in 69% (14), 76% (21) and 61% (9). 64% of the latter group received sucralfate. Worsening occurred in 7% (6). Treatment length varied with a median of 4 weeks (range 4-20 weeks). CONCLUSIONS: This study showed poorer therapy outcome compared to previous studies. The only initial lesion descriptor to predict outcome was severity and treatment choice did not affect outcome.
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Doenças dos Cavalos , Misoprostol , Úlcera Gástrica , Cavalos , Animais , Úlcera Gástrica/veterinária , Estudos Retrospectivos , Sucralfato , Omeprazol/uso terapêutico , Doenças dos Cavalos/tratamento farmacológicoRESUMO
INTRODUCTION: Depression may influence treatment participation and outcomes of people with post-stroke aphasia, yet its prevalence and associated characteristics in aphasia are poorly understood. Using retrospective data from an overarching experimental study, we examined depressive symptoms and their relationship to demographic and language characteristics in people with chronic aphasia. As a secondary objective, we compared prevalence of depressive symptoms among the overarching study's included and excluded participants. METHODS: We examined retrospective data from 121 individuals with chronic aphasia including depression scale scores, demographic information (sex, age, time post onset of stroke, education, race/ethnicity, and Veteran status), and scores on assessments of general and modality-specific language impairments. RESULTS: Approximately 50% of participants reported symptoms indicative of depressive disorders: 23% indicative of major depression and 27% indicative of mild depression. Sex (males) and comparatively younger age emerged as statistically significant variables associated with depressive symptoms; naming ability was minimally associated with depressive symptoms. Time post onset of stroke, education level, race/ethnicity, Veteran status, and aphasia severity were not significantly associated with depressive symptoms. Depression-scale scores were significantly higher for individuals excluded from the overarching study compared to those who were included. CONCLUSIONS: The rate of depressive disorders in this sample was higher than rates of depression reported in the general stroke literature. Participant sex, age, and naming ability emerged as factors associated with depressive symptoms, though these links appear complex, especially given variable reports from prior research. Importantly, depressive symptoms do not appear to diminish over time for individuals with chronic aphasia. Given these results and the relatively limited documentation of depression in aphasia literature, depression remains a pressing concern for aphasia research and routine clinical care.
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Afasia , Transtornos do Desenvolvimento da Linguagem , Acidente Vascular Cerebral , Masculino , Humanos , Depressão/etiologia , Estudos Retrospectivos , Afasia/etiologia , Acidente Vascular Cerebral/complicações , PrevalênciaRESUMO
NADK2 encodes the mitochondrial form of nicotinamide adenine dinucleotide (NAD) kinase, which phosphorylates NAD. Rare recessive mutations in human NADK2 are associated with a syndromic neurological mitochondrial disease that includes metabolic changes, such as hyperlysinemia and 2,4 dienoyl CoA reductase (DECR) deficiency. However, the full pathophysiology resulting from NADK2 deficiency is not known. Here, we describe two chemically induced mouse mutations in Nadk2-S326L and S330P-which cause severe neuromuscular disease and shorten lifespan. The S330P allele was characterized in detail and shown to have marked denervation of neuromuscular junctions by 5 weeks of age and muscle atrophy by 11 weeks of age. Cerebellar Purkinje cells also showed progressive degeneration in this model. Transcriptome profiling on brain and muscle was performed at early and late disease stages. In addition, metabolomic profiling was performed on the brain, muscle, liver and spinal cord at the same ages and on plasma at 5 weeks. Combined transcriptomic and metabolomic analyses identified hyperlysinemia, DECR deficiency and generalized metabolic dysfunction in Nadk2 mutant mice, indicating relevance to the human disease. We compared findings from the Nadk model to equivalent RNA sequencing and metabolomic datasets from a mouse model of infantile neuroaxonal dystrophy, caused by recessive mutations in Pla2g6. This enabled us to identify disrupted biological processes that are common between these mouse models of neurological disease, as well as those processes that are gene-specific. These findings improve our understanding of the pathophysiology of neuromuscular diseases and describe mouse models that will be useful for future preclinical studies.
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Hiperlisinemias , Distrofias Neuroaxonais , Animais , Camundongos , Humanos , NAD/genética , Distrofias Neuroaxonais/genética , Distrofias Neuroaxonais/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas Mitocondriais/genética , Fosfolipases A2 do Grupo VI/genéticaRESUMO
The objective of this study was to determine effects of maternal nutrient restriction (NR) during early or mid-gestation on uterine composition and miRNA expression in cotyledons. Primiparous Angus-cross cows (n = 38) were synchronized and inseminated using male sexed semen, blocked by body condition score and body weight (BW), and assigned to treatments. Animals were fed either: control (CON; gain 1 kg/week) or NR (55% maintenance energy and crude protein requirements) based on BW. An initial set of animals were fed either NR (n = 8) or CON (n = 8) from day 30-110 of gestation. A second set of animals were fed CON (n = 8) d 30-190 (CON/CON); NR (n = 7) day 30-110 followed by CON day 110-190 (NR/CON); or CON (n = 7) day 30-110 followed by NR day 110-190 (CON/NR). Cows were harvested on day 110 or 190 of gestation to collect placental tissues. RNA was isolated from cotyledon samples (3 animals/group) prior to microarray analysis using known Bos taurus microRNA sequences. Relative microRNA abundance was analyzed via ANOVA. Maternal NR increased (P < 0.05) cotyledon weight and total placentome surface area irrespective of gestational day. At day 110 of gestation, 51 microRNAs were reduced while 91 microRNAs observed greater abundance (P < 0.05) in NR verses CON cotyledons. At day 190 of gestation, 40 microRNAs were reduced and 26 microRNAs were increased (P < 0.05) in both NR/CON and CON/NR verses CON cotyledons. Top KEGG pathway analysis included: axon guidance, endocytosis, neuroactive ligand receptor interaction, and MAPK signaling pathway. Early-gestation maternal NR altered microRNA abundance to a greater extent than mid-gestation NR.
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Fenômenos Fisiológicos da Nutrição Animal , MicroRNAs , Animais , Bovinos , Cotilédone , Dieta/veterinária , Fenômenos Fisiológicos da Nutrição Materna , MicroRNAs/genética , Nutrientes , Placenta , Placentação , GravidezRESUMO
Enhanced efficiency fertilisers (EEF) may reduce nitrogen (N) losses and improve uptake efficiency through synchronising N release with in-season plant requirements. We hypothesised that EEF formed via matrix encapsulation in biodegradable polymers will improve N use efficiency when compared to conventional urea fertiliser. This hypothesis was investigated for two biodegradable polymer matrices: polyhydroxyalkanoate (PHA), containing 11.6% urea (by mass), and polybutylene-adipate-co-terephthalate (PBAT), containing either 19.4 or 32.7% urea; and two contrasting soil types: sand and clay. Nitrogen availability and form was investigated under leaching conditions (water) with a growth accelerator pot experiment involving a horticultural crop and novel non-destructive three-dimensional scanning to measure in-season biomass development. The PBAT 32.7% formulation enabled greater above ground biomass production at both 50 and 100 kg N ha-1 equivalent application rates compared to conventional urea. For the sandy soil, plant scanning indicated that improved uptake performance with PBAT 32.7% was probably the result of greater N availability after 25 days than for conventional urea. Two of the encapsulated formulations (PHA and PBAT 19.4%) tended to decrease nitrogen leaching losses relative to urea (P < 0.05 for the red clay soil). However, decreased N leaching loss was accompanied by poorer N uptake performance, indicative of N being less available in these biopolymer formulations. A snapshot of nitrous oxide emissions collected during peak nitrate concentration (prior to planting and leaching) suggested that the biopolymers promoted N loss via gaseous emission relative to urea in the sandy soil (P < 0.05), and carbon dioxide emissions data suggested that biopolymer-carbon increased microbial activity (P < 0.1). Controlled testing of N release in water was a poor predictor of biomass production and leaching losses. The diverse behaviours of the tested formulations present the potential to optimise biopolymers and their N loadings by taking into account soil and environmental factors that influence the efficient delivery of N to target crops. The greater N uptake efficiency demonstrated for the PBAT 32.7% formulation confirms our hypothesis that matrix encapsulation can enable better synchronisation of N release with crop requirements and decrease leaching losses.
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Fertilizantes , Objetivos , Agricultura , Produtos Agrícolas , Fertilizantes/análise , Nitrogênio/análise , Polímeros , SoloRESUMO
INTRODUCTION: Kuwait has a shortage of radiologists, especially in mammography, resulting in increased workload and longer waiting times for women receiving imaging investigations. This study looked at how radiographers and radiologists perceived radiographers' role extension (RE) in mammography, and whether this could reduce radiologist workload, thereby improving patient service and waiting times. METHODS: A single case study design with 10 radiographers (mammographers) and 10 radiologists was undertaken across multiple sites: hospitals, screening clinics and specialist centres in Kuwait. Data included individual semi-structured interviews, documentary analysis and field notes. Perceptions were examined under a theoretical framework, Abbotts' System of Professions. RESULTS: Two main themes were identified, firstly in examining the current role of radiographers in mammography and areas of interest for extending role, this highlighted insufficient knowledge of the concept. The second focused on in-depth understanding of drivers and barriers to RE in mammography, both groups opposed radiographers performing extended tasks without radiologist supervision. CONCLUSION: Radiologists and radiographers' attitudes were influenced by concepts of professional identity and professional identity formation. Insufficient professional knowledge negatively affected the radiographers' readiness to undertake RE in mammography. Radiologists are reluctant to blur boundaries, enabling them to maintain and control jurisdiction of their own profession and that of radiographers, thereby, as discussed in Abbott's theory, limiting impact on workload or waiting times. IMPLICATIONS FOR PRACTICE: Whilst RE is limited, to improve workload and patient waiting times, setting up an educational programme for radiographers specialising in mammography would be an important step to extending the radiographers' role. The study highlighted a need to educate radiographers to undertake breast ultrasound and amend policy to introduce training programmes for radiographers. Radiographer rotation across the various radiographic modalities negatively affected radiographers' performance, placing well-trained radiographers permanently within the mammography department should improve experience and overall skills.
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Pessoal Técnico de Saúde , Radiologistas , Atitude , Feminino , Humanos , Kuweit , MamografiaRESUMO
We present a comparison of the photoionization dynamics of the 4d shell of XeF2 from threshold to 250 eV to those of the prototypical 4d shell of atomic Xe. The new experimental data include spin-orbit and ligand-field-resolved partial cross sections, photoelectron angular distributions, branching fractions, and lifetime widths for the 4d-hole states. The spin-orbit branching fractions and angular distributions are remarkably similar to the corresponding distributions from atomic Xe across a broad energy interval that includes both the intense shape resonance in the f continuum and a Cooper minimum in the same channel. The angular distributions and branching fractions are also in reasonably good agreement with our first-principles theoretical calculations on XeF2. Data are also presented on the lifetime widths of the substate-resolved 4d-hole states of XeF2. While the trends in the widths are similar to those in the earlier experimental and theoretical work, the linewidths are considerably smaller than in the previous measurements, which may require some reinterpretation of the decay mechanism. Finally, we present new data and an analysis of the Auger electron spectra for ionization above the 4d thresholds and resonant Auger spectra for several pre-edge features.
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Dominant mutations in ubiquitously expressed transfer RNA (tRNA) synthetase genes cause axonal peripheral neuropathy, accounting for at least six forms of Charcot-Marie-Tooth (CMT) disease. Genetic evidence in mouse and Drosophila models suggests a gain-of-function mechanism. In this study, we used in vivo, cell typespecific transcriptional and translational profiling to show that mutant tRNA synthetases activate the integrated stress response (ISR) through the sensor kinase GCN2 (general control nonderepressible 2). The chronic activation of the ISR contributed to the pathophysiology, and genetic deletion or pharmacological inhibition of Gcn2 alleviated the peripheral neuropathy. The activation of GCN2 suggests that the aberrant activity of the mutant tRNA synthetases is still related to translation and that inhibiting GCN2 or the ISR may represent a therapeutic strategy in CMT.
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Doença de Charcot-Marie-Tooth/metabolismo , Glicina-tRNA Ligase/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico , Tirosina-tRNA Ligase/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/fisiopatologia , Modelos Animais de Doenças , Feminino , Deleção de Genes , Genes Dominantes , Glicina-tRNA Ligase/genética , Masculino , Camundongos , Camundongos Mutantes , Neurônios Motores/fisiologia , Biossíntese de Proteínas , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Medula Espinal/fisiopatologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia , Transcriptoma , Tirosina-tRNA Ligase/genéticaRESUMO
Linearly polarized synchrotron radiation has been used to record polarization dependent valence shell photoelectron spectra of imidazole in the photon energy range 21-100 eV. These have allowed the photoelectron angular distributions, as characterized by the anisotropy parameter ß, and the electronic state intensity branching ratios to be determined. Complementing these experimental data, theoretical photoionization partial cross sections and ß-parameters have been calculated for the outer valence shell orbitals. The assignment of the structure appearing in the experimental photoelectron spectra has been guided by vertical ionization energies and spectral intensities calculated by various theoretical methods that incorporate electron correlation and orbital relaxation. Strong orbital relaxation effects have been found for the 15a', nitrogen lone-pair orbital. The calculations also predict that configuration mixing leads to the formation of several low-lying satellite states. The vibrational structure associated with ionization out of a particular orbital has been simulated within the Franck-Condon model using harmonic vibrational modes. The adiabatic approximation appears to be valid for the X 2Aâ³ state, with the ß-parameter for this state being independent of the level of vibrational excitation. However, for all the other outer valence ionic states, a disparity occurs between the observed and the simulated vibrational structure, and the measured ß-parameters are at variance with the behavior expected at the level of the Franck-Condon approximation. These inconsistencies suggest that the excited electronic states may be interacting vibronically such that the nuclear dynamics occur over coupled potential energy surfaces.
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Single-photon, photoelectron-photoion coincidence spectroscopy is used to record the mass-selected ion spectra and slow photoelectron spectra of C4H5 radicals produced by the abstraction of hydrogen atoms from three C4H6 precursors by fluorine atoms generated by a microwave discharge. Three different C4H5 isomers are identified, with the relative abundances depending on the nature of the precursor (1-butyne, 1,2-butadiene, and 1,3-butadiene). The results are compared with our previous work using 2-butyne as a precursor [Hrodmarsson, H. R. J. Phys. Chem. A 2019, 123, 1521-1528]. The slow photoelectron spectra provide new information on the three radical isomers that is in good agreement with previous experimental and theoretical results [Lang, M. J. Phys. Chem. A 2015, 119, 3995-4000; Hansen, N. J. Phys. Chem. A 2006, 110, 3670-3678]. The energy scans of the C4H5 photoionization signal are recorded with substantially better resolution and signal-to-noise ratio than those in earlier work, allowing the observation of autoionizing resonances based on excited states of the C4H5 cation. Photoelectron images recorded at several energies are also reported, providing insight into the decay processes of these excited states. Finally, in contrast to the earlier work using 2-butyne as a precursor, where H-atom abstraction was the only observed process, F- and H-atom additions to the present precursors are also observed through the detection of C4H6F, C4H5F, and C4H7.
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A dopamine type-2 receptor (DRD2) SNP, previously found to be correlated with serum prolactin (PRL) concentrations in cattle, was evaluated for impact on growth traits, serum prolactin concentration, and semen quality. Over a four-year period, yearling beef bulls were allowed diets containing or lacking ergot alkaloids (EA). Every 21 or 28 d semen was collected for semen motility and morphology assessment and blood samples were collected to measure serum PRL concentrations. In addition, body condition score and scrotal circumference were evaluated. Serum PRL concentrations were assessed using a radioimmunoassay. In the first year, all bulls were sacrificed at the end of a 126-day study. Testicles and epididymis were collected at the end of the study or 60 days after removal from treatment. Immunohistochemistry was performed on testis, epididymis, and sperm cells, incubated with or without a primary antibody for DRD2 and counterstained with DAPI. Isolation of DNA was performed on sperm pellets using DNAzol (Thermo Fisher Scientific, Waltham, MA, USA) methods. Polymerase chain reaction was performed to amplify the region of the DRD2 gene containing the SNP of interest. The products were subjected to restriction fragment length polymorphism analysis. Further, all samples were subjected to genotyping using a custom Taqman genotyping assay (Applied Biosystems, Foster city, CA, USA). The presence of DRD2 was detected in the testis, epididymis, and sperm cells. The DRD2 genotype was not associated with semen quality, serum PRL, or growth traits. Consumption of EA resulted in lesser PRL serum concentrations but had no effect on values for other variable examined.
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Bovinos , Agonistas de Dopamina/farmacologia , Crescimento e Desenvolvimento , Polimorfismo de Nucleotídeo Único , Prolactina/sangue , Receptores de Dopamina D2/genética , Sêmen/efeitos dos fármacos , Animais , Constituição Corporal/genética , Bovinos/sangue , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Dopamina/sangue , Genótipo , Crescimento e Desenvolvimento/efeitos dos fármacos , Crescimento e Desenvolvimento/genética , Masculino , Sêmen/metabolismo , Sêmen/fisiologia , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides/efeitos dos fármacos , Motilidade dos Espermatozoides/genéticaRESUMO
The C 1s ionization spectrum of CH3I has been studied both experimentally and theoretically. Synchrotron radiation has been employed to record polarization dependent photoelectron spectra at a photon energy of 614 eV. These spectra encompass the main-line due to the C 1s single-hole state and the peaks associated with the shake-up satellites. Vertical ionization energies and relative photoelectron intensities have been computed using the fourth-order algebraic-diagrammatic construction approximation scheme for the one-particle Green's function and the 6-311++G** basis set. The theoretical spectrum derived from these calculations agrees qualitatively with the experimental results, thereby allowing the principal spectral features to be assigned. According to our calculations, two 2A1 shake-up states of the C 1s-1 σCI â σCI * type with singlet and triplet intermediate coupling of the electron spins (S' = 0, 1) play an important role in the spectrum and contribute significantly to the overall intensity. Both of these states are expected to have dissociative diabatic potential energy surfaces with respect to the C-I separation. Whereas the upper of these states perturbs the manifold of Rydberg states, the lower state forms a band which is characterized by a strongly increased width. Our results indicate that the lowest shake-up peak with significant spectral intensity is due to the pair (S' = 0, 1) of 2E (C 1s-1 I 5p â σCI *) states. We predict that these 2E states acquire photoelectron intensity due to spin-orbit interaction. Such interactions play an important role here due to the involvement of the I 5p orbitals.
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Mobile technology provides a unique opportunity to expand access to evidence-based interventions. The objective of this study was to provide an update regarding use of technology in people with serious mental illness (SMI). In 2017, 403 people in treatment for SMI were surveyed. Technology use was common: 65.8% used a smartphone, 53.6% used the Internet on a computer or tablet in the past 6 months, and over two thirds (67.9%) used social media. Rates of technology and Facebook use were similar to rates among low-income Americans. Approximately three quarters were willing to use a device to access interventions for stress, health and mental health. Younger adults were more likely to use most forms of technology and social media compared to older adults, but willingness to try technology-delivered interventions did not vary by age. This survey supports the rationale for ongoing development and testing of digital interventions for people with SMI.
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Computadores/estatística & dados numéricos , Transtornos Mentais , Smartphone/estatística & dados numéricos , Mídias Sociais/estatística & dados numéricos , Adulto , Idoso , Centros Comunitários de Saúde Mental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados UnidosRESUMO
The hydroxyl free radical, OH, is one of the most important radicals in atmospheric and interstellar chemistry, and its cation plays a role in the reactions leading to H2O formation. Knowledge of the photoionization efficiency of the OH radical is crucial to properly model the water photochemical cycle of atmospheres and astrophysical objects. Using a gas-phase radical source based on a single H-abstraction reaction combined with a photoelectron/photoion imaging coincidence spectrometer coupled with synchrotron radiation, we recorded the OH+ photoion yield over the 12.6-15 eV energy range, and we set it to an absolute cross section scale using an absolute point measurement performed at 13.8 eV: σOH ion=9.0±2.7 Mb. The resulting cross section values differ by approximately a factor 2 from the recent measurement of Dodson et al. [J. Chem. Phys. 148, 184302 (2018)] performed with a different radical source, which is somewhat greater than the combined uncertainties of the measurements. This finding underlines the need for further investigations of this cross section.
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We present new high-resolution data on the photoionization of the 2-butyn-1-yl radical (CH3C≡C-â¢CH2) formed by H atom abstraction from 2-butyne by F atoms. The spectra were recorded from 7.7 to 11 eV by using double-imaging, photoelectron-photoion coincidence spectroscopy, which allows the unambiguous correlation of photoelectron data and the mass of the species. The photoionization spectrum shows significant resonant autoionizing structure converging to excited states of the C4H5+ cation, similar to what is observed in the closely related propargyl radical (HC≡C-â¢CH2). The threshold photoelectron spectrum, obtained with a resolution of 17 meV, is also reported. This spectrum is consistent with previous measurements of the first photoionization band but has been extended to higher energy to allow the observation of bands corresponding to excited electronic states of the ion. A refined value of the adiabatic ionization energy is extracted: IE(C4H5) = 7.93 ± 0.01 eV. A determination of the absolute photoionization cross section of the 2-butyn-1-yl radical at 9.7 eV is also reported: σion(C4H5) = 6.1 ± 1.8 Mb.
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BACKGROUND: There is no information directly comparing midazolam with guaifenesin when used in combination with an alpha-2 agonist and ketamine to maintain anaesthesia via i.v. infusion in horses. OBJECTIVES: To compare ketamine-medetomidine-guaifenesin with ketamine-medetomidine-midazolam for total intravenous anaesthesia (TIVA) in young horses anaesthetised for computerised tomography. STUDY DESIGN: Prospective, randomised, blinded, crossover trial. METHODS: Fourteen weanlings received medetomidine 7 µg/kg bwt i.v. and anaesthesia was induced with ketamine 2.2 mg/kg bwt i.v. On two separate occasions horses each received infusions of ketamine 3 mg/kg bwt/h, medetomidine 5 µg/kg bwt/h, guaifenesin 100 mg/kg bwt/h (KMG) or ketamine 3 mg/kg bwt/h, medetomidine 5 µg/kg bwt/h, midazolam 0.1 mg/kg bwt/h (KMM) for 50 min. Cardiorespiratory variables and anaesthetic depth were assessed every 5-10 min. Recovery times after the infusions ceased were recorded and recovery quality was assessed using a composite score system (CSS), simple descriptive scale (SDS) and visual analogue scale (VAS). Multivariable models were used to generate mean recovery scores for each treatment and each recovery score system and provide P-values comparing treatment groups. RESULTS: Anaesthesia was uneventful with no difference in additional anaesthetic requirements and little clinically relevant differences in cardiopulmonary variables between groups. All horses recovered without incident with no significant difference in recovery times. Quality of the anaesthetic recovery was significantly better for the KMM group compared with the KMG group using the CSS (P<0.001), SDS (P<0.001) and VAS (P<0.001). MAIN LIMITATIONS: No surgical stimulus was applied and study animals may not represent general horse population. CONCLUSION: Midazolam is a suitable alternative to guaifenesin when co-infused with ketamine and medetomidine for anaesthesia in young horses undergoing noninvasive procedures. Both infusions produce a clinically comparable quality of anaesthesia; however, recovery from anaesthesia is of a better quality following an infusion of ketamine-medetomidine-midazolam.
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Anestésicos Intravenosos/farmacologia , Guaifenesina/farmacologia , Cavalos , Ketamina/farmacologia , Medetomidina/farmacologia , Midazolam/farmacologia , Anestesia Intravenosa/veterinária , Anestésicos Intravenosos/administração & dosagem , Animais , Estudos Cross-Over , Quimioterapia Combinada , Expectorantes/administração & dosagem , Expectorantes/farmacologia , Feminino , Guaifenesina/administração & dosagem , Hipnóticos e Sedativos/administração & dosagem , Ketamina/administração & dosagem , Masculino , Medetomidina/administração & dosagem , Midazolam/administração & dosagem , Distribuição Aleatória , Tomografia Computadorizada por Raios X/veterináriaRESUMO
The objective of this study was to evaluate semen quality and fertility in beef bulls grazing the ergot alkaloid (EA) producing tall fescue cultivar, Kentucky 31 (KY31), compared to a novel endophyte (NE) cultivar lacking EA. Two studies were conducted over a 3-year period. In studies 1 (nâ¯=â¯10; agesâ¯≥â¯24â¯mo) and 2 (nâ¯=â¯53 over two years; ages 12-16â¯mo), Angus (AN) bulls were stratified by body weight (BW), body condition score (BCS), and scrotal circumference (SC), and then allotted to graze either KY31 or NE for 56 days. Semen samples were collected, and BW, BCS, and SC were evaluated at the start of treatment (TRT) on day (d) 0 and every 28 days to the end of each study. In addition, blood samples were collected on d 0 and every 28 days for assessment of circulating prolactin (PRL) levels in study 2. On d 56, for both studies, semen from bulls (nâ¯=â¯2 per treatment in study 1 and nâ¯=â¯4 per treatment in study 2) with similar and acceptable quality were extended, kept at 19° C, and used for timed artificial insemination (TAI) of primi- and multiparous AN and AN- crossbred females. Pregnancy was evaluated at 35 and 90 days post-TAI via transrectal ultrasonography to determine pregnancy rates. Serum PRL concentrations showed a TRT by d effect (Pâ¯≤â¯0.05), with values for bulls grazing KY31 decreased on d 28 and d 56 of grazing compared to NE. In studies 1 and 2, bull BW and BCS were affected by d (Pâ¯≤â¯0.05), but not by TRT. No TRT or TRT by d effect on semen quality was observed in either study; however, d impacted both velocity and concentration in study 2 (Pâ¯≤â¯0.05). In study 1, TAI pregnancy rates at 35 days post-TAI were lower (Pâ¯≤â¯0.05) in the group inseminated with semen from bulls grazing KY31; however, in study 2, pregnancy rates did not differ due to treatment 35 post-TAI (Pâ¯>â¯0.05). Grazing KY31 negatively impacted serum PRL concentrations, supporting previous observations; however, consumption of KY31 had no effect on growth or semen quality of AN bulls ranging from 12 to ≥24â¯mo of age. Furthermore, fertility data is inconsistent between studies and requires further investigation.
Assuntos
Alcaloides de Claviceps/efeitos adversos , Fertilidade/efeitos dos fármacos , Análise do Sêmen/veterinária , Sêmen/efeitos dos fármacos , Envelhecimento , Ração Animal/análise , Animais , Bovinos , Alcaloides de Claviceps/metabolismo , Feminino , Festuca/metabolismo , Inseminação Artificial/veterinária , Masculino , Gravidez , Taxa de Gravidez , Prolactina/sangue , Escroto/anatomia & histologiaRESUMO
The single-photon, photoelectron-photoion coincidence spectrum of N2 has been recorded at high (â¼1.5 cm-1) resolution in the region between the N2+ X Σg2+, v+ = 0 and 1 ionization thresholds by using a double-imaging spectrometer and intense vacuum-ultraviolet light from the Synchrotron SOLEIL. This approach provides the relative photoionization cross section, the photoelectron energy distribution, and the photoelectron angular distribution as a function of photon energy. The region of interest contains autoionizing valence states, vibrationally autoionizing Rydberg states converging to vibrationally excited levels of the N2+ X Σg2+ ground state, and electronically autoionizing states converging to the N2+A2Π and B 2Σu+ states. The wavelength resolution is sufficient to resolve rotational structure in the autoionizing states, but the electron energy resolution is insufficient to resolve rotational structure in the photoion spectrum. A simplified approach based on multichannel quantum defect theory is used to predict the photoelectron angular distribution parameters, ß, and the results are in reasonably good agreement with experiment.