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3.
Domest Anim Endocrinol ; 84-85: 106806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37392553

RESUMO

Recent research has suggested that different cattle breed types may respond differently to anabolic implant protocols of varying intensity. Therefore, the purpose of this research was to compare anabolic implant protocols in feedlot steers of 2 different breed types. Sixty steers were stratified by weight and breed in a 2 × 3 factorial design examining 2 different breeds: Angus (AN; n=38) or Santa Gertrudis influenced (SG; n=22), and 3 implant strategies: no implant (CON; n=20), a moderate intensity implant protocol (d0 implant: Revalor-G, d56 implant: Revalor-IS, d112 implant: Revalor-S; MI; n=20), or a high intensity implant protocol (d0 implant: Revalor-IS, d56 implant: Revalor-S, d112 implant: Revalor-200; HI; n=20). Steers were randomly placed into pens equipped with GrowSafe bunks to collect dry matter intake and feeding behavior. All animals were fed the same diet. Weight, chute score, exit velocity, serum, rectal temperature, hip height and 12th rib fat thickness were collected approximately every 28 d over a 196 d period. Serum urea nitrogen (SUN) was evaluated as well. Total average daily gain was increased (P < 0.0001) in both the HI and MI steers compared to the CON steers by 29.4% and 26%, respectively. A treatment × breed interaction was observed (P < 0.0001) for hip height, with AN-CON steers being shorter (P < 0.0007) than AN-HI, SG-CON, SG-MI, and SG-HI steers. A breed × treatment interaction was observed (P < 0.004) for chute score and rectal temperature, with SG-HI and SG-MI steers having increased chute scores (P < 0.001) when compared to AN-HI, AN-MI, AN-CON, and SG-CON throughout the course of the trial. Additionally, SG-HI and SG-MI steers had an increased rectal temperature (P < 0.004) compared to AN-HI, AN-MI, AN-CON, and SG-CON steers. A breed effect was observed (P = 0.002) for SUN with AN steers having increased (P = 0.002) SUN concentration compared to SG sired steers, in addition to a treatment effect (P < 0.0001), with CON steers having a higher (P < 0.0001) SUN concentration than MI and HI steers, regardless of breed. The MI implant protocol increased net return per head, on average, by $97.28, regardless of breed, while the HI implant protocol increased net return by only $80.84. Taken together, despite the cattle breed types responding differently to the different anabolic implant protocols at times, a moderate intensity anabolic implant protocol was optimal in this experiment for steers raised in a temperate climate.


Assuntos
Dieta , Temperamento , Animais , Bovinos/genética , Ração Animal/análise , Nitrogênio da Ureia Sanguínea , Composição Corporal , Dieta/veterinária , Comportamento Alimentar
4.
Emerg Microbes Infect ; 12(1): 2154617, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36458572

RESUMO

ABSTRACTMutations in the SARS-CoV-2 genome may negatively impact a diagnostic test, have no effect, or turn into an opportunity for rapid molecular screening of variants. Using an in-house Emergency Use Authorized RT-qPCR-based COVID-19 diagnostic assay, we combined sequence surveillance of viral variants and computed PCR efficiencies for mismatched templates. We found no significant mismatches for the N, E, and S set of assay primers until the Omicron variant emerged in late November 2021. We found a single mismatch between the Omicron sequence and one of our assay's primers caused a > 4 cycle delay during amplification without impacting overall assay performance.Starting in December 2021, clinical specimens received for COVID-19 diagnostic testing that generated a Cq delay greater than 4 cycles were sequenced and confirmed as Omicron. Clinical samples without a Cq delay were largely confirmed as the Delta variant. The primer-template mismatch was then used as a rapid surrogate marker for Omicron. Primers that correctly identified Omicron were designed and tested, which prepared us for the emergence of future variants with novel mismatches to our diagnostic assay's primers. Our experience demonstrates the importance of monitoring sequences, the need for predicting the impact of mismatches, their value as a surrogate marker, and the relevance of adapting one's molecular diagnostic test for evolving pathogens.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Teste para COVID-19 , Saúde Pública , SARS-CoV-2/genética
5.
Domest Anim Endocrinol ; 82: 106773, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36375404

RESUMO

The majority of beef cattle in the United States often receive at least one anabolic implant resulting in improved growth, feed efficiency, and environmental and economic sustainability. However, the physiological and molecular mechanisms through which anabolic implants increase skeletal muscle growth of beef cattle remain elusive. The objective of this study was to identify transcriptional changes occurring in skeletal muscle of steers receiving anabolic implants containing different steroid hormones. Forty-eight steers were stratified by weight into 1 of 4 (n = 12/treatment) implant treatment groups: (1) estradiol (ImpE2; 25.7 mg E2; Compudose, Elanco Animal Health, Greenfield, IN), (2) trenbolone acetate (ImpTBA; 200 mg TBA; Finaplix-H, Merck Animal Health, Madison, NJ), (3) combination (ImpETBA; 120 mg TBA + 24 mg E2; Revalor-S, Merck Animal Health), or (4) no implant (CON). Skeletal muscle biopsies were taken from the longissimus 2 and 10 d post-implantation. The mRNA abundance of 94 genes associated with skeletal muscle growth was examined. At 10 d post-implantation, steers receiving ImpETBA had greater (P = 0.02) myoblast differentiation factor 1 transcript abundance than CON. Citrate synthase abundance was increased (P = 0.04) in ImpETBA steers compared to CON steers. In ImpE2 steers 10 d post-implantation, muscle RING finger protein 1 decreased (P = 0.05) compared to CON steers, and forkhead box protein O4 decreased (P = 0.05) in ImpETBA steers compared to CON steers. Interleukin-6 abundance tended to be increased (P = 0.09) in ImpE2 steers compared to both ImpETBA and CON steers. Furthermore, interleukin-10 mRNA abundance tended to be increased (P = 0.06) in ImpTBA steers compared to ImpETBA steers. Leptin receptor abundance was reduced (P = 0.01) in both ImpE2 and ImpTBA steers when compared to CON steers. Abundance of phosphodiesterase 4B was increased (P = 0.04) in ImpTBA steers compared to CON steers 2 d post-implantation. Taken together, the results of this research demonstrate that estradiol increases skeletal muscle growth via pathways related to nutrient partitioning and mitochondria function, while trenbolone acetate improves steer skeletal muscle growth via pathways related to muscle growth.


Assuntos
Doenças dos Bovinos , Acetato de Trembolona , Animais , Bovinos , RNA Mensageiro/genética , Acetato de Trembolona/farmacologia , Inflamação/veterinária , Músculo Esquelético , Estradiol
6.
J Synchrotron Radiat ; 28(Pt 3): 688-706, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949979

RESUMO

The high-precision X-ray diffraction setup for work with diamond anvil cells (DACs) in interaction chamber 2 (IC2) of the High Energy Density instrument of the European X-ray Free-Electron Laser is described. This includes beamline optics, sample positioning and detector systems located in the multipurpose vacuum chamber. Concepts for pump-probe X-ray diffraction experiments in the DAC are described and their implementation demonstrated during the First User Community Assisted Commissioning experiment. X-ray heating and diffraction of Bi under pressure, obtained using 20 fs X-ray pulses at 17.8 keV and 2.2 MHz repetition, is illustrated through splitting of diffraction peaks, and interpreted employing finite element modeling of the sample chamber in the DAC.

8.
QJM ; 114(9): 648-653, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33471128

RESUMO

BACKGROUND: Cocooning or shielding, i.e. staying at home and reducing face-to-face interaction with other people, was an important part of the response to the COVID-19 pandemic for older people. However, concerns exist regarding the long-term adverse effects cocooning may have on their physical and mental health. AIM: To examine health trajectories and healthcare utilization while cocooning in a cohort of community-dwelling people aged ≥70 years. DESIGN: Survey of 150 patients (55% female, mean age 80 years and mean Clinical Frailty Scale Score 4.8) attending ambulatory medical services in a large urban university hospital. METHODS: The survey covered four broad themes: access to healthcare services, mental health, physical health and attitudes to COVID-19 restrictions. Survey data were presented descriptively. RESULTS: Almost 40% (59/150) reported that their mental health was 'worse' or 'much worse' while cocooning, while over 40% (63/150) reported a decline in their physical health. Almost 70% (104/150) reported exercising less frequently or not exercising at all. Over 57% (86/150) of participants reported loneliness with 1 in 8 (19/150) reporting that they were lonely 'very often'. Half of participants (75/150) reported a decline in their quality of life. Over 60% (91/150) agreed with government advice for those ≥70 years but over 40% (61/150) reported that they disliked the term 'cocooning'. CONCLUSIONS: Given the likelihood of further restrictions in coming months, clear policies and advice for older people around strategies to maintain social engagement, manage loneliness and continue physical activity and access timely medical care and rehabilitation services should be a priority.


Assuntos
COVID-19 , Pandemias , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Saúde Mental , Qualidade de Vida , SARS-CoV-2
9.
QJM ; 114(1): 32-38, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32866245

RESUMO

BACKGROUND: Up to half of patients presenting with falls, syncope or dizziness are admitted to hospital. Many are discharged without a clear diagnosis for their index episode, however, and therefore a relatively high risk of readmission. AIM: To examine the impact of ED-FASS (Emergency Department Falls and Syncope Service) a dedicated specialist service embedded within an ED, seeing patients of all ages with falls, syncope and dizziness. DESIGN: Pre- and post-cohort study. METHODS: Admission rates, length of stay (LOS) and readmission at 3 months were examined for all patients presenting with a fall, syncope or dizziness from April to July 2018 (pre-ED-FASS) inclusive and compared to April to July 2019 inclusive (post-ED-FASS). RESULTS: There was a significantly lower admission rate for patients presenting in 2019 compared to 2018 [27% (453/1676) vs. 34% (548/1620); X2 = 18.0; P < 0.001], with a 20% reduction in admissions. The mean LOS for patients admitted in 2018 was 20.7 [95% confidence interval (CI) 17.4-24.0] days compared to 18.2 (95% CI 14.6-21.9) days in 2019 (t = 0.98; P = 0.3294). This accounts for 11 344 bed days in the 2018 study period, and 8299 bed days used after ED-FASS. There was also a significant reduction in readmission rates within 3 months of index presentation, from 21% (109/1620) to 16% (68/1676) (X2 = 4.68; P = 0.030). CONCLUSION: This study highlights the significant potential benefits of embedding dedicated multidisciplinary services at the hospital front door in terms of early specialist assessment and directing appropriate patients to effective ambulatory care pathways.


Assuntos
Acidentes por Quedas , Tontura , Readmissão do Paciente , Estudos de Coortes , Serviço Hospitalar de Emergência , Humanos , Tempo de Internação , Estudos Retrospectivos , Síncope
10.
APL Photonics ; 6(5)2021.
Artigo em Inglês | MEDLINE | ID: mdl-37621960

RESUMO

We developed superconducting nanowire single-photon detectors based on tungsten silicide, which show saturated internal detection efficiency up to a wavelength of 10 µm. These detectors are promising for applications in the mid-infrared requiring sub-nanosecond timing, ultra-high gain stability, low dark counts, and high efficiency, such as chemical sensing, LIDAR, dark matter searches, and exoplanet spectroscopy.

12.
QJM ; 113(3): 155-161, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30825309

RESUMO

Midlife Type II diabetes mellitus (T2DM) is an important yet often unrecognized risk factor for the later development of dementia. We conducted a systematic review to assess the efficacy of non-pharmacological interventions (namely diet, exercise and cognitive training) for T2DM on cognition. A search strategy was constructed and applied to four databases: EMBASE, Medline, CINAHL and Web of Science. Peer-reviewed journal articles in English were considered assessing the effect of exercise, dietary or cognitive training/stimulation-based interventions (or any combination of these) in patients with T2DM on cognition. Results were dual-screened and extracted by two independent reviewers. Of 4820 results, 3782 remained after de-duplication. Forty full-texts were screened and two studies were included in the final review. The first assessed the impact of a 10-year intensive lifestyle intervention on T2DM-related complications (Look-AHEAD study) and the second was a post hoc analysis of T2DM patients from a trial of a physical activity intervention in older non-demented adult with functional limitations (LIFE study). Whilst the Look-AHEAD study found no impact on diagnosis of mild cognitive impairment or dementia, the LIFE study demonstrated beneficial effects on global cognitive function and delayed memory specifically in older adults with T2DM. There is insufficient evidence to fully assess the effect of non-pharmacological interventions on cognition in T2DM. Well-constructed trials must be designed to specifically assess the effect of non-pharmacological and multi-domain interventions for cognition in patients with T2DM in midlife. All trials examining interventions in T2DM should consider cognition as at least a secondary outcome.


Assuntos
Disfunção Cognitiva/terapia , Diabetes Mellitus Tipo 2/terapia , Cognição , Disfunção Cognitiva/etiologia , Dieta , Exercício Físico , Humanos , Estilo de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Diabet Med ; 37(8): 1299-1307, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31770459

RESUMO

AIMS: Orthostatic hypotension is a recognized complication of diabetes, but studies examining prevalence in diabetes are limited. The aim of this study was to ascertain the prevalence of orthostatic hypotension and the pattern of orthostatic BP response in a cohort of people with diabetes aged ≥ 50 years, embedded within the Irish Longitudinal Study of Ageing. METHODS: Orthostatic hypotension was defined as a drop in systolic blood pressure (SBP) ≥ 20 mmHg or drop in diastolic blood pressure (DBP) ≥ 10 mmHg at 30 s after standing. Diabetes was defined by self-report but cross-checked against HbA1c and medication records. Multilevel mixed effects linear regression models were used to compare orthostatic BP in people with and without diabetes. RESULTS: Some 3222 people were included, 7% (213 of 3222) of whom had diabetes. Prevalence of orthostatic hypotension in the group with diabetes was 22% (46 of 213) vs. 13% in those without diabetes; χ2 = 12.43; P < 0.001. Multilevel models demonstrated prolonged recovery of DBP in people with diabetes, with only 41% (87 of 213) returning to baseline by 60 s. Logistic regression models demonstrated that diabetes was associated with a significantly increased likelihood of orthostatic hypotension (odds ratio 1.84, 95% confidence interval 1.30-2.59; P = 0.001) and this remained robust after controlling for covariates. CONCLUSION: Over one-fifth of older people with diabetes had orthostatic hypotension. Recovery of DBP is related to dynamic changes in total peripheral resistance and impairment of this baroreflex-mediated response may explain the higher prevalence in diabetes. Given the prognostic implications when co-existing with diabetes, orthostatic hypotension may represent a potentially modifiable risk factor for adverse outcomes in late-life diabetes.


Assuntos
Diabetes Mellitus/epidemiologia , Hipotensão Ortostática/epidemiologia , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Vida Independente , Irlanda/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade
14.
Phys Rev Lett ; 123(4): 045701, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31491279

RESUMO

We combined laser shock compression with in situ x-ray diffraction to probe the crystallographic state of gold (Au) on its principal shock Hugoniot. Au has long been recognized as an important calibration standard in diamond anvil cell experiments due to the stability of its face-centered cubic (fcc) structure to extremely high pressures (P >600 GPa at 300 K). This is in contrast to density functional theory and first principles calculations of the high-pressure phases of Au that predict a variety of fcc-like structures with different stacking arrangements at intermediate pressures. In this Letter, we probe high-pressure and high-temperature conditions on the shock Hugoniot and observe fcc Au at 169 GPa and the first evidence of body-centered cubic (bcc) Au at 223 GPa. Upon further compression, the bcc phase is observed in coexistence with liquid scattering as the Hugoniot crosses the Au melt curve before 322 GPa. The results suggest a triple point on the Au phase diagram that lies very close to the principal shock Hugoniot near ∼220 GPa.

15.
Phys Rev Lett ; 122(25): 255704, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31347883

RESUMO

Ultrafast x-ray diffraction at the LCLS x-ray free electron laser has been used to resolve the structural behavior of antimony under shock compression to 59 GPa. Antimony is seen to transform to the incommensurate, host-guest phase Sb-II at ∼11 GPa, which forms on nanosecond timescales with ordered guest-atom chains. The high-pressure bcc phase Sb-III is observed above ∼15 GPa, some 8 GPa lower than in static compression studies, and mixed Sb-III/liquid diffraction are obtained between 38 and 59 GPa. An additional phase which does not exist under static compression, Sb-I^{'}, is also observed between 8 and 12 GPa, beyond the normal stability field of Sb-I, and resembles Sb-I with a resolved Peierls distortion. The incommensurate Sb-II high-pressure phase can be recovered metastably on release to ambient pressure, where it is stable for more than 10 ns.

16.
Geophys Res Lett ; 46(3): 1348-1356, 2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-31007309

RESUMO

Recent experiments have demonstrated the existence of previously unknown iron oxides at high pressure and temperature including newly discovered pyrite-type FeO2 and FeO2Hx phases stable at deep terrestrial lower mantle pressures and temperatures. In the present study, we probed the iron oxidation state in high-pressure transformation products of Fe3+OOH goethite by in situ X-ray absorption spectroscopy in laser-heated diamond-anvil cell. At pressures and temperatures of ~91 GPa and 1,500-2,350 K, respectively, that is, in the previously reported stability field of FeO2Hx, a measured shift of -3.3 ± 0.1 eV of the Fe K-edge demonstrates that iron has turned from Fe3+ to Fe2+. We interpret this reductive valence change of iron by a concomitant oxidation of oxygen atoms from O2- to O-, in agreement with previous suggestions based on the structures of pyrite-type FeO2 and FeO2Hx phases. Such peculiar chemistry could drastically change our view of crystal chemistry in deep planetary interiors.

17.
J Synchrotron Radiat ; 26(Pt 1): 96-101, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30655473

RESUMO

Time-resolved X-ray diffraction measurements have been carried out on dynamically compressed Sn up to a maximum pressure of ∼13 GPa at the European Synchrotron Radiation Facility. The phase transition from ß-Sn to body-centered tetragonal (b.c.t.) Sn has been observed using synchrotron X-ray diffraction for the first time undergoing shock compression and release. Following maximum compression, the sample releases to lower pressures for several nanoseconds until the reverse transition occurs. The data are in good agreement with previous shock boundaries that indicate that the ß-Sn phase is stable ∼2 GPa higher than the static boundary upon compression and the b.c.t.-Sn phase is stable ∼1 GPa lower upon release. The transition to the high-pressure phase reveals a loss of texture in the X-ray diffraction data from the `quasi' single-crystal ß-Sn structure to a more powder-like Debye-Scherrer ring.

18.
Sci Rep ; 8(1): 16927, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30446720

RESUMO

Bismuth has long been a prototypical system for investigating phase transformations and melting at high pressure. Despite decades of experimental study, however, the lattice-level response of Bi to rapid (shock) compression and the relationship between structures occurring dynamically and those observed during slow (static) compression, are still not clearly understood. We have determined the structural response of shock-compressed Bi to 68 GPa using femtosecond X-ray diffraction, thereby revealing the phase transition sequence and equation-of-state in unprecedented detail for the first time. We show that shocked-Bi exhibits a marked departure from equilibrium behavior - the incommensurate Bi-III phase is not observed, but rather a new metastable phase, and the Bi-V phase is formed at significantly lower pressures compared to static compression studies. We also directly measure structural changes in a shocked liquid for the first time. These observations reveal new behaviour in the solid and liquid phases of a shocked material and give important insights into the validity of comparing static and dynamic datasets.

19.
J Laryngol Otol ; 132(11): 1000-1006, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30370884

RESUMO

OBJECTIVE: To identify the intracochlear electrode position in cochlear implant recipients and determine the correlation to speech perception for two peri-modiolar electrode arrays. METHODS: Post-operative cone-beam computed tomography images of 92 adult recipients of the 'CI512' electrode and 18 adult recipients of the 'CI532' electrode were analysed. Phonemes scores were recorded pre-implantation, and at 3 and 12 months post-implantation. RESULTS: All CI532 electrodes were wholly within scala tympani. Of the 79 CI512 electrodes intended to be in scala tympani, 58 (73 per cent) were in scala tympani, 14 (17 per cent) were translocated and 7 (9 per cent) were wholly in scala vestibuli. Thirteen CI512 electrodes were deliberately inserted into scala vestibuli. Speech perception scores for post-lingual recipients were higher in the scala tympani group (69.1 per cent) compared with the scala vestibuli (54.2 per cent) and translocation (50 per cent) groups (p < 0.05). Electrode location outside of scala tympani independently resulted in a 10.5 per cent decrease in phoneme scores. CONCLUSION: Cone-beam computed tomography was valuable for demonstrating electrode position. The rate of scala tympani insertion was higher in CI532 than in CI512 electrodes. Scala vestibuli insertion and translocation were associated with poorer speech perception outcomes.


Assuntos
Implante Coclear/instrumentação , Rampa do Tímpano/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Tomografia Computadorizada de Feixe Cônico , Eletrodos Implantados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Percepção da Fala
20.
J Am Soc Hypertens ; 12(8): 597-604.e1, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29937420

RESUMO

Orthostatic hypotension (OH) is often reported as a significant potential adverse effect of antidepressant use but the association between phasic blood pressure (BP) and antidepressants has not yet been investigated. This cross-sectional study compares continuously measured phasic BP and prevalence of OH in a cohort of antidepressant users ≥50 years compared with an age- and sex-matched cohort not taking antidepressants. OH was defined as a drop in systolic BP ≥ 20 mm Hg or in diastolic BP ≥ 10 mm Hg at 30 seconds after standing, measured using continuous beat-to-beat finometry. Multilevel time × group interactions revealed significantly greater systolic and diastolic BP drop in antidepressant users than nonusers at 30 seconds after stand. The prevalence of OH among antidepressant users was 31% (63/206), compared with 17% in nonusers (X2 = 9.7; P = .002). Unadjusted logistic regression models demonstrated that selective serotonin reuptake inhibitor use was associated with OH at an odds ratio of 2.11 (95% confidence interval: 1.25-3.57); P = .005, and this association was not attenuated when covariates including cardiac disease and depressive symptom burden were added. There was no statistically significant association between serotonin noradrenaline reuptake inhibitor or tricyclic antidepressant use and OH in unadjusted models although the study was not powered to detect changes within these subgroups. Older people taking antidepressants have a two-fold higher prevalence of OH than nonusers, highlighting the importance of screening the older antidepressant user for OH and dizziness and rationalizing medications to reduce the risk of falls within this vulnerable cohort.

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