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1.
J Am Chem Soc ; 146(13): 8915-8927, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38517290

RESUMEN

A barrier to understanding the factors driving catalysis in the oxygen evolution reaction (OER) is understanding multiple overlapping redox transitions in the OER catalysts. The complexity of these transitions obscure the relationship between the coverage of adsorbates and OER kinetics, leading to an experimental challenge in measuring activity descriptors, such as binding energies, as well as adsorbate interactions, which may destabilize intermediates and modulate their binding energies. Herein, we utilize a newly designed optical spectroelectrochemistry system to measure these phenomena in order to contrast the behavior of two electrocatalysts, cobalt oxyhydroxide (CoOOH) and cobalt-iron hexacyanoferrate (cobalt-iron Prussian blue, CoFe-PB). Three distinct optical spectra are observed in each catalyst, corresponding to three separate redox transitions, the last of which we show to be active for the OER using time-resolved spectroscopy and electrochemical mass spectroscopy. By combining predictions from density functional theory with parameters obtained from electroadsorption isotherms, we demonstrate that a destabilization of catalytic intermediates occurs with increasing coverage. In CoOOH, a strong (∼0.34 eV/monolayer) destabilization of a strongly bound catalytic intermediate is observed, leading to a potential offset between the accumulation of the intermediate and measurable O2 evolution. We contrast these data to CoFe-PB, where catalytic intermediate generation and O2 evolution onset coincide due to weaker binding and destabilization (∼0.19 eV/monolayer). By considering a correlation between activation energy and binding strength, we suggest that such adsorbate driven destabilization may account for a significant fraction of the observed OER catalytic activity in both materials. Finally, we disentangle the effects of adsorbate interactions on state coverages and kinetics to show how adsorbate interactions determine the observed Tafel slopes. Crucially, the case of CoFe-PB shows that, even where interactions are weaker, adsorption remains non-Nernstian, which strongly influences the observed Tafel slope.

2.
Vet Anaesth Analg ; 51(1): 35-43, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38016893

RESUMEN

OBJECTIVE: Novel locoregional techniques use dye studies to confirm successful nerve targeting. The goal was to objectively quantify and compare nerve staining characteristics of dye mixtures commonly reported in the literature using image analysis software. STUDY DESIGN: Prospective, randomized cadaveric study. METHODS: Thirty-six brachial plexus nerves from unpreserved pig cadavers were randomized into three groups of 12: FD (1:10 mixture of blue food dye and bupivacaine 0.5%), MB (methylene blue 1%) and TM (0.1:10 mixture of blue tissue marker and lidocaine 2%). Nerves were immersed in dye for 1, 15, 30 or 60 minutes (n = 3 each). Images of nerves before immersion (baseline) and at each time point with epineurium intact (superficial staining) and after longitudinal bisection (deep staining) were processed using image analysis software. Color saturation values were divided into quartiles (dark, medium-dark, medium-light or light). Percentage of stained nerve area in each quartile was calculated and compared using two-way anova. RESULTS: Superficially, at minute 1, dark saturation covered 40% of nerve area in FD versus 19% in MB (p = 0.04) and 0% in TM (p < 0.0001). In bisected nerves, dark and medium-dark saturations occurred only in FD; medium-light saturation comprised anywhere from 4% to 22.5% over time in FD versus <1% at any time in MB (p = 1.000; p = 0.343; p = 0.383; p = 0.262). Deep staining was not found in TM at any point. CONCLUSION AND CLINICAL RELEVANCE: Food dye rapidly stains superficial and deep nerve layers. Based on these characteristics, investigators can choose the appropriate dye for their study.


Asunto(s)
Plexo Braquial , Bloqueo Nervioso , Enfermedades de los Porcinos , Animales , Porcinos , Bloqueo Nervioso/veterinaria , Bloqueo Nervioso/métodos , Azul de Metileno , Estudios Prospectivos , Plexo Braquial/anatomía & histología , Coloración y Etiquetado/veterinaria , Cadáver , Ultrasonografía Intervencional/métodos , Ultrasonografía Intervencional/veterinaria
3.
Vet Anaesth Analg ; 50(6): 492-497, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37805279

RESUMEN

OBJECTIVE: To compare the effects of intramuscular premedication with a novel nonanalgesic [alfaxalone-midazolam-acepromazine (AMA)] and an analgesic [ketamine-midazolam-detomidine (KMD)] protocol on sedation end points and propofol requirements for induction of anesthesia in swine. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of 27 Yorkshire cross gilts weighing approximately 30 kg. METHODS: Two sedation protocols, AMA and KMD, were compared. Time from intramuscular injection to ataxia, recumbency and nonresponsiveness to tactile stimulation was recorded. The propofol dose requirement for induction of general anesthesia and tracheal intubation, and any adverse events (paddling, twitching), were recorded. Data were tested for normality using a Shapiro-Wilk test. Propofol requirements were compared using a Student's t test. Times from injection to sedation end points were compared using a Mood's test, and significance was confirmed using a Kaplan-Meier curve with Wilcoxon test survival analysis. RESULTS: Sedation end points were reached significantly faster with KMD than with AMA. Nonresponsiveness occurred in 5 (0-16) and 9.5 (5-36) minutes for KMD and AMA, respectively (p = 0.011). No significant difference (p = 0.437) was found between propofol doses used in either group (KMD; 64.38 ± 5.98 mg, AMA; 72.00 ± 7.57 mg). More adverse events were noted with AMA (11/16 pigs) than with KMD (1/11 pigs). CONCLUSIONS AND CLINICAL RELEVANCE: In pigs, AMA can be used as a reliable sedation protocol. Frequency of adverse events and time to reach sedation end points between AMA and KMD differed, but the dose of propofol needed to induce general anesthesia was not significantly different.


Asunto(s)
Analgesia , Ketamina , Propofol , Porcinos , Animales , Femenino , Midazolam , Anestésicos Intravenosos , Estudios Prospectivos , Anestesia General/veterinaria , Analgesia/veterinaria , Hipnóticos y Sedantes
4.
Angew Chem Int Ed Engl ; 62(45): e202312645, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37723118

RESUMEN

CO2 hydrogenation to methanol has the potential to serve as a sustainable route to a wide variety of hydrocarbons, fuels and plastics in the quest for net zero. Synergistic Pd/In2 O3 (Palldium on Indium Oxide) catalysts show high CO2 conversion and methanol selectivity, enhancing methanol yield. The identity of the optimal active site for this reaction is unclear, either as a Pd-In alloy, proximate metals, or distinct sites. In this work, we demonstrate that metal-efficient Pd/In2 O3 species dispersed on Al2 O3 can match the performance of pure Pd/In2 O3 systems. Further, we follow the evolution of both Pd and In sites, and surface species, under operando reaction conditions using X-ray Absorption Spectroscpy (XAS) and infrared (IR) spectroscopy. In doing so, we can determine both the nature of the active sites and the influence on the catalytic mechanism.

5.
Am J Obstet Gynecol ; 226(2): 187-204.e15, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34384776

RESUMEN

OBJECTIVE: We conducted a systematic review and meta-analysis to comprehensively compare cardiometabolic and reproductive health risk between Hispanic and White women with polycystic ovary syndrome in the United States in response to the call by the international guideline for polycystic ovary syndrome to delineate health disparities. DATA SOURCES: Databases of MEDLINE, Web of Science, and Scopus were initially searched through October 25, 2020, and confirmed on February 1, 2021. STUDY ELIGIBILITY CRITERIA: Observational studies comparing glucoregulatory, lipid profile, anthropometric, blood pressure, androgen, ovarian morphology, oligoanovulation, and infertility status between Hispanic and White women with polycystic ovary syndrome were included. The primary outcome was metabolic syndrome risk. Furthermore, major cardiovascular events (stroke, coronary heart disease, and heart failure) and mortality rate (cardiovascular death and total mortality) data were evaluated. Studies on adolescents (<2 years after menarche), pregnant, or menopausal-aged women (>50 years) were excluded. METHODS: Data were pooled by random-effects models and expressed as mean differences and 95% confidence intervals. Risk of bias was assessed by the Newcastle-Ottawa Scale. RESULTS: A total of 11 studies (n=2267; 589 Hispanic and 1678 White women) were eligible. All studies, including both White and Hispanic women, had high-quality assessment (Newcastle-Ottawa Scale score of ≥8). Hispanic women exhibited comparable metabolic syndrome prevalence (7% [95% confidence interval, -1 to 14]; P=.06; I2=0%); however, Hispanic women exhibited higher modified Ferriman-Gallwey score (0.60 [95% confidence interval, -0.01 to 1.21]; P=.05; I2=0%), fasting insulin (5.48 µIU/mL [95% confidence interval, 3.11-7.85]; P≤.01; I2=40.0%), and homeostatic model assessment of insulin resistance (1.20 [95% confidence interval, 0.50-1.89]; P≤.01; I2=43.0%) than White women. The 2 groups had comparable glucose, lipid profile, waist circumference, blood pressure, and androgen status (all P≥.08). Findings about group differences in certain reproductive outcomes (ie, ovarian dysmorphology and infertility) were contradictory and described only narratively as inclusion in the meta-analyses was not possible. No study reported on cardiovascular events or mortality. CONCLUSION: Hispanic women with polycystic ovary syndrome exhibited greater impairments in glucoregulatory status than White women. Disparities in reproductive risks could not be concluded. The degree to which glucoregulatory aberrations translate into patient-pressing diseases (diabetes mellitus and infertility) remains a major roadblock given the paucity of available evidence. Our observations have supported the consideration of these disparities in the diagnostic, monitoring, and management practices for polycystic ovary syndrome and reinforced the need to elucidate mechanisms that account for the observed disparities to foster equity in polycystic ovary syndrome care.


Asunto(s)
Síndrome Metabólico/epidemiología , Síndrome del Ovario Poliquístico/epidemiología , Presión Sanguínea/fisiología , Femenino , Hispánicos o Latinos , Humanos , Síndrome Metabólico/fisiopatología , Síndrome del Ovario Poliquístico/fisiopatología , Prevalencia , Riesgo , Estados Unidos , Población Blanca
6.
Vet Surg ; : O33-O42, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34985136

RESUMEN

OBJECTIVE: To determine the rate of full-length publication for the 2004-2019 Veterinary Endoscopy Society (VES) annual meeting abstracts and to identify abstract and author characteristics as predictors of publication. STUDY DESIGN: Observational bibliographical study. SAMPLE POPULATION: Three hundred and eighty-nine abstracts. METHODS: Abstracts from 2004-2019 Veterinary Endoscopy Society (VES) proceedings and matching full-length publications retrieved from bibliographic databases were systematically reviewed. Variables assessed included species, specimen type (cadaver, live animal, etc.), subdiscipline (orthopedics, internal medicine, etc.), institution, country of origin, study design, level of evidence (LoE), time to publication, number of authors, their credentials, and gender. Logistic regression, Fisher's exact tests and t-tests were used to assess the bivariate relationship between publication and characteristics of the authors and publications. RESULTS: The overall publication rate for presented abstracts published as full-length articles in peer-reviewed journals was 26%. Median time from abstract presentation to full-length article publication was 430 days. Factors associated with full-length article publication were identified: affiliated institution (P = .01), species studied (P = .04), subdiscipline focus (P = .01), level of evidence (P = .01), number of authors (P = .01), and first author's gender (P = .03). CONCLUSION: Veterinary Endoscopy Society abstracts were commonly categorized into a lower LoE. Abstracts from academic institutions regarding canine patients and soft tissue surgery topics were more likely to be published. Abstracts citing female first authors or with more than 1 author had higher odds of publication. CLINICAL SIGNIFICANCE: Data reported provide authors with predictors for publication and identify topics for research opportunities. Veterinary specialty societies may utilize this information when evaluating abstracts.

7.
Vet Anaesth Analg ; 49(1): 95-103, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34893433

RESUMEN

OBJECTIVE: Several factors affect the quality of recovery from general anesthesia in horses. These can increase the likelihood of injury. Body and limb position during recovery may correlate with successful standing. The objective of this study was to identify the prevalence of and the factors associated with successful standing at the first attempt in horses undergoing general anesthesia. STUDY DESIGN: Retrospective study. METHODS: Video of recovery and anesthetic records from 221 equine patients were reviewed by six veterinary students. Cases with poor video quality or incomplete anesthetic records were excluded. Demographic variables, type of procedure, perioperative drugs administered, assistance during recovery and body and limb positions during the first attempt to stand were recorded. Association between putative variables (including specific descriptors for body and limb position) and success for standing were analyzed using backward logistic regression; significance was set at 0.05. A decision tree for a successful attempt was created to predict the outcome of a recovery attempt based on these variables. RESULTS: Extension of the carpal joints, head and neck alignment with the thoracic limbs, greater time in lateral recumbency, coordination during sternal recumbency, longer time to first attempt to stand and pelvic limb position were associated with successful standing at the first attempt. The association between extension of the carpal joints with wide base positioning of the pelvic limbs provided the best success rate for standing, whereas the association of flexed carpal joints and head and neck orientation different from the thoracic limbs resulted in a worse success rate. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that certain limb and body positions displayed by horses during recovery may be associated with the likelihood of successful standing at the first attempt. These variables may be useful for assessing recovery quality in future research.


Asunto(s)
Periodo de Recuperación de la Anestesia , Anestesia General , Anestesia General/veterinaria , Animales , Miembro Anterior , Caballos , Prevalencia , Estudios Retrospectivos
8.
Am J Obstet Gynecol ; 224(5): 428-444.e8, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33316275

RESUMEN

OBJECTIVE: We conducted a systematic review and meta-analysis to summarize and quantitatively pool evidence on cardiometabolic health disparities between Black and White women with polycystic ovary syndrome in the United States in response to the call for further delineation of these disparities in the international evidence-based guideline for the assessment and management of polycystic ovary syndrome. DATA SOURCES: Databases of MEDLINE, Web of Science, and Scopus were searched initially through March 05, 2020, and confirmed on September 11, 2020. STUDY ELIGIBILITY CRITERIA: Observational studies documenting cardiometabolic risk profile (glucoregulatory, lipid profile, anthropometric, and blood pressure status) in Black and White women with polycystic ovary syndrome were included. Studies on children (<17 years old) and pregnant or menopausal-aged women (>50 years) were excluded. The primary outcome was fasting glucose. Furthermore, data on major cardiovascular events (stroke, coronary heart disease, heart failure) and mortality rate (cardiovascular death, total mortality) were evaluated. METHODS: Data were pooled by random-effects models and expressed as mean differences and 95% confidence intervals. Studies were weighted based on the inverse of the variance. Heterogeneity was evaluated by Cochran Q and I2 statistics. Study methodologic quality was assessed by the Newcastle-Ottawa scale. RESULTS: A total of 11 studies (N=2851 [652 Black and 2199 White]) evaluated cardiometabolic risk profile and all had high quality (Newcastle-Ottawa scale score of ≥8). No studies reported on cardiovascular events and mortality rate. Black women had comparable fasting glucose (-0.61 [-1.69 to 2.92] mg/dL; I2=62.5%), yet exhibited increased fasting insulin (6.76 [4.97-8.56] µIU/mL; I2=59.0%); homeostatic model assessment of insulin resistance (1.47 [0.86-2.08]; I2=83.2%); systolic blood pressure (3.32 [0.34-6.30] mm Hg; I2=52.0%); and decreased triglyceride (-32.56 [-54.69 to -10.42] mg/dL; I2=68.0%) compared with White women (all, P≤.03). Groups exhibited comparable total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and diastolic blood pressure (all, P≥.06). CONCLUSIONS: Black women with polycystic ovary syndrome have a greater tendency for an adverse cardiometabolic risk profile (increased insulin, homeostatic model assessment of insulin resistance, and systolic blood pressure) despite lower triglycerides than White women. Our observations support the consideration of these disparities for diagnostic, monitoring, and management practices in Black women and for future guideline recommendations. Given the heterogeneity among studies, future research should address the relative contributions of biologic, environmental, socioeconomic, and healthcare factors to the observed disparities. Furthermore, longitudinal research is required to address patient-pressing complications, including cardiovascular events and mortality rate in Black women with polycystic ovary syndrome as a high-risk yet understudied population.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Factores de Riesgo Cardiometabólico , Enfermedades Cardiovasculares/epidemiología , Disparidades en el Estado de Salud , Síndrome del Ovario Poliquístico/epidemiología , Población Blanca/estadística & datos numéricos , Glucemia/metabolismo , Presión Sanguínea , Enfermedades Cardiovasculares/mortalidad , Ayuno , Femenino , Humanos , Insulina/sangre , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/fisiopatología , Triglicéridos/sangre , Estados Unidos/epidemiología
9.
Phytopathology ; 111(11): 1972-1982, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33829855

RESUMEN

Hop powdery mildew, caused by the ascomycete fungus Podosphaera macularis, is a consistent threat to sustainable hop production. The pathogen utilizes two reproductive strategies for overwintering and perennation: (i) asexual vegetative hyphae on dormant buds that emerge the following season as infected shoots; and (ii) sexual ascocarps (chasmothecia), which are discharged during spring rain events. We demonstrate that P. macularis chasmothecia, in the absence of any asexual P. macularis growth forms, are a viable overwintering source capable of causing early season infection two to three orders of magnitude greater than that reported for perennation via asexual growth. Two epidemiological models were defined that describe (i) temperature-driven maturation of P. macularis chasmothecia; and (ii) ascosporic discharge in response to duration of leaf wetness and prevailing temperatures. P. macularis ascospores were confirmed to be infectious at temperatures ranging from 5 to 20°C. The organism's chasmothecia were also found to adhere tightly to the host tissue on which they formed, suggesting that these structures likely overwinter wherever hop tissue senesces within a hop yard. These observations suggest that existing early season disease management practices are especially crucial to controlling hop powdery mildew in the presence of P. macularis chasmothecia. Furthermore, these insights provide a baseline for the validation of weather-driven models describing maturation and release of P. macularis ascospores, models that can eventually be incorporated into hop disease management programs.


Asunto(s)
Ascomicetos , Humulus , Enfermedades de las Plantas/microbiología , Ascomicetos/patogenicidad , Humulus/microbiología
10.
Vet Anaesth Analg ; 48(2): 223-229, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33536139

RESUMEN

OBJECTIVE: To collect data about the current practice of recovering horses from general anesthesia and recovery personnel safety. STUDY DESIGN: Online survey. METHODS: An online questionnaire, including questions on general demographic data, recovery drugs, modality and characteristics of equine recovery and morbidity and mortality, was designed and distributed via e-mail to equine practitioners worldwide. RESULTS: Practitioners from 22 countries completed 373 questionnaires; 53% of the participants were board-certified equine surgeons, and the remainder were board-certified anesthesiologists (18%), large animal residents (8%), general practitioners (7%), large animal interns (6%), anesthesia residents (4.5%) and veterinary technicians (1.6%). Respondents were employed by academia (58%) or private practice (42%). Of the respondents employed at a university, 93% had a board-certified anesthesiologist on staff compared with 7% of respondents employed at a private practice. Most of the respondents assist horses during recovery, with 23% assisting every recovery and 44% assisting recovery in the majority of cases. Reasons for choosing to assist horses during recovery were: orthopedic procedures (57%), neurological deficits (49%), bad health (47%), history of poor recovery (44%), foals (42%), draft breeds (30%), magnetic resonance imaging (17%) and computed tomography (16%). Unacceptable recoveries were reported by 77% of participants. Commonly reported complications during recovery with any method were: orthopedic injury (66%), myopathy (54%), skin abrasion (53%) and airway obstruction (37%). The incidences of unacceptable quality of recovery (p = 0.09) or personnel injury (p = 0.56) were not different between assisted and nonassisted recoveries; however, more equine fatalities were reported for assisted recoveries (p < 0.006). Practitioners in academia reported more unacceptable recoveries (p < 0.0007) and personnel injuries (p < 0.002) compared with those in private practice. CONCLUSIONS: The method of recovery differs among hospitals. Recovery personnel injuries associated with assisting horses during recovery are an important and previously unreported finding.


Asunto(s)
Anestesia General , Enfermedades de los Caballos , Periodo de Recuperación de la Anestesia , Anestesia General/veterinaria , Animales , Caballos , Encuestas y Cuestionarios
11.
Vet Ophthalmol ; 23(4): 674-681, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32369267

RESUMEN

OBJECTIVE: To determine the efficacy of a single treatment of topical and subconjunctival 0.1% preservative-free morphine sulfate (PFMS) in providing analgesia following phacoemulsification in dogs. ANIMALS STUDIED: Ten diabetic and ten non-diabetic client-owned dogs treated with bilateral phacoemulsification. PROCEDURES: A prospective, randomized, masked, negative-controlled clinical trial was performed. All dogs received topical (0.2 mL) and subconjunctival (0.1 mL) 0.1% PFMS in one eye following phacoemulsification. The other eye received an equal volume and mode of administration of balanced salt solution (BSS). Ophthalmic examination, blinking rates, tearing, conjunctival hyperemia, aqueous flare, and central corneal esthesiometry (CCE) were evaluated in all eyes 1 day prior to surgery and at 4, 24, and 48 hours after surgery. Complete physical examination, ocular ultrasound, electroretinogram, hemogram, and serum biochemistry panel were performed in all dogs prior to phacoemulsification. All dogs received the standard of care treatment before and after surgery, including uniform anesthetic protocol. RESULTS: Baseline ophthalmic exams were unremarkable, except for the presence of cataracts, in all dogs. The mean CCE (±SD) at 4 hours post-operatively was 1.76 ± 1.27 g/mm2 and 1.85 ± 1.5 g/mm2 for the negative control and PFMS groups, respectively. There were no statistical differences in blepharospasm, conjunctival hyperemia, tearing, aqueous flare, blinking rates, CCE, or intraocular pressure (IOP) between the treatment groups for any of the time points for the non-diabetic and diabetic dogs, or for all dogs combined (P > .05). CONCLUSIONS: Topical and subconjunctival 0.1% PFMS did not affect the evaluated parameters after phacoemulsification in the study dogs at the timepoints assessed.


Asunto(s)
Analgésicos/uso terapéutico , Enfermedades de los Perros/cirugía , Perros/fisiología , Morfina/uso terapéutico , Soluciones Oftálmicas/uso terapéutico , Dolor Postoperatorio/veterinaria , Facoemulsificación/veterinaria , Administración Tópica , Analgésicos/administración & dosificación , Animales , Femenino , Masculino , Morfina/administración & dosificación , Soluciones Oftálmicas/administración & dosificación , Dolor Postoperatorio/prevención & control , Proyectos Piloto , Estudios Prospectivos , Resultado del Tratamiento
12.
Vet Ophthalmol ; 22(5): 623-632, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30775837

RESUMEN

OBJECTIVE: To describe and to establish normative data for the feline optic nerve and peripapillary retina using SD-OCT (Spectralis® HRA+OCT2). METHODS: Slit-lamp biomicroscopy and rebound tonometry were performed in seven male-intact (0.65 ± 0.02 years;4.34 ± 0.33 kg) and seven female-spayed (0.74 ± 0.03 years; 3.13 ± 0.28 kg) cats. All eyes were pharmacologically dilated with 1% tropicamide prior to indirect ophthalmoscopy examination. Animals were then placed under general anesthesia. Optic nerve and peripapillary retinal morphology was evaluated using SD-OCT device by infrared imaging and volumetric scans (circle and radial). Optic disc area, optic cup depth, peripapillary retinal thickness (RT), and retinal nerve fiber layer thickness (RNFLT) were measured. The RNFLT:RT ratio was calculated in the superior, nasal, temporal, and inferior peripapillary region. RESULTS: Intraocular pressure in all cats was 20.68 ± 4.87 mm Hg (mean ± SD). Mean RT and RNFL were thickest in the superior retina (264.7 ± 13.95 µm and 70.22 ± 11.78 µm, respectively) (P < 0.0001). Inferior RT was significantly thinner than nasal and temporal retina (P = 0.0013 and P = 0.0010, respectively). The RNFLT:RT was significantly higher in the superior retina (0.27 ± 0.04) (P < 0.0001). Optic disc area OU was 1.39 ± 0.26 mm2 . Optic cup depth OU was 168.36 ± 67.74 µm. All parameters tested were not affected by gender, intraocular pressure, body weight, or tested eye. Most eyes had a Bergmeister papilla that was only visible on OCT. Some animals had a recessed area over the center of the ONH meniscus. CONCLUSION: Normative peripapillary ONH OCT data have been introduced. A Bergmeister papillae is commonly seen in young cats on OCT examination. OCT is a helpful tool to evaluate the retina in cats.


Asunto(s)
Gatos/anatomía & histología , Nervio Óptico/diagnóstico por imagen , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/veterinaria , Animales , Femenino , Masculino , Disco Óptico/diagnóstico por imagen , Valores de Referencia
13.
J Synchrotron Radiat ; 25(Pt 4): 953-959, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29979155

RESUMEN

Although remote access to beamline synchrotron facilities is now a common operation mode at macromolecular crystallography beamlines thanks to substantial efforts in automated processes for sample preparation and handling, experiment planning and analysis, this is still not the case for XAFS beamlines. Here the experience and developments undertaken at LNLS and Diamond in automation are described, in an attempt to tackle the specific challenges posed by the high variability in experimental conditions and configurations that XAFS measurements require.

14.
J Synchrotron Radiat ; 25(Pt 4): 998-1009, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29979161

RESUMEN

This manuscript presents the current status and technical details of the Spectroscopy Village at Diamond Light Source. The Village is formed of four beamlines: I18, B18, I20-Scanning and I20-EDE. The village provides the UK community with local access to a hard X-ray microprobe, a quick-scanning multi-purpose XAS beamline, a high-intensity beamline for X-ray absorption spectroscopy of dilute samples and X-ray emission spectroscopy, and an energy-dispersive extended X-ray absorption fine-structure beamline. The optics of B18, I20-scanning and I20-EDE are detailed; moreover, recent developments on the four beamlines, including new detector hardware and changes in acquisition software, are described.

15.
Mutagenesis ; 33(3): 231-239, 2018 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-30239864

RESUMEN

Accurate quantification of DNA double strand breaks (DSB) in testicular germ cells is difficult because of cellular heterogeneity and the presence of endogenous γH2AX. Here, we used confocal microscopy to quantify DNA damage and repair kinetics following γ-irradiation (0.5-4 Gy) in three major mouse male germ cell stages, early and late pachytene spermatocytes and round spermatids (RSs), following a defined post irradiation time course. Dose-response curves showing linear best fit validated γH2AX focus as a rapid biodosimetric tool in these substages in response to whole body in vivo exposure. Stage specific foci yield/dose and repair kinetics demonstrated differential radiosensitivity and repair efficiency: early pachytenes (EP) repaired most rapidly and completely followed by late pachytene (LP) and RSs. Repair kinetics for all three stages followed 'exponential decay' in response to each radiation dose. In pachytenes immediate colocalisation of γH2AX and 53BP1, which participates in non-homologous end-joining repair pathway, was followed by dissociation from the major focal area of γH2AX by 4 h demonstrating ongoing DSB repair. These results confirm the differential radiosensitivity and repair kinetics of DSBs in male germ cells at different stages. Taken together, our results provide a simple and accurate method for assessing DNA damage and repair kinetics during spermatogenesis.


Asunto(s)
Reparación del ADN/efectos de la radiación , Histonas/genética , Espermatocitos/efectos de la radiación , Proteína 1 de Unión al Supresor Tumoral P53/genética , Animales , Roturas del ADN de Doble Cadena/efectos de la radiación , Daño del ADN/genética , Daño del ADN/efectos de la radiación , Reparación del ADN por Unión de Extremidades/genética , Reparación del ADN/genética , Rayos gamma/efectos adversos , Cinética , Masculino , Ratones , Fase Paquiteno/genética , Fase Paquiteno/efectos de la radiación , Dosis de Radiación , Radiometría , Espermátides/crecimiento & desarrollo , Espermátides/efectos de la radiación , Espermatocitos/crecimiento & desarrollo
16.
J Public Health (Oxf) ; 39(4): 863-873, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28069993

RESUMEN

Background: Understanding health beliefs and how they influence willingness will enable the development of targeted curricula that maximize public engagement in Alzheimer's disease (AD) risk reduction behaviors. Methods: Literature on behavioral theory and community input was used to develop and validate a health beliefs survey about AD risk reduction among 428 community-dwelling adults. Principal component analysis was performed to assess internal consistency. Linear regression was performed to identify key predictors of Willingness to engage in AD risk reduction behaviors. Results: The measure as well as the individual scales (Benefits, Barriers, Severity, Susceptibility and Social Norm) were found to be internally consistent. Overall, as Benefits and Barriers scores increased, Willingness scores also increased. Those without prior AD experience or family history had lower willingness scores. Finally, we observed an interaction between age and norms, suggesting that social factors related to AD prevention may differentially affect people of different ages. Conclusions: The Alzheimer Prevention Beliefs Measure provides assessment of several health belief factors related to AD prevention. Age, Family History, Logistical Barriers and total Benefits are significant determinants of willingness to engage in AD risk reduction behaviors, such as seeing a doctor or making a lifestyle change.


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Enfermedad de Alzheimer/psicología , Conocimientos, Actitudes y Práctica en Salud , Medición de Riesgo/métodos , Medición de Riesgo/normas , Encuestas y Cuestionarios/normas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Investigación Participativa Basada en la Comunidad , Etnicidad , Femenino , Conductas Relacionadas con la Salud , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Conducta de Reducción del Riesgo , Autoinforme/normas , Adulto Joven
17.
Appl Geochem ; 54: 27-42, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26109747

RESUMEN

Highly reactive nano-scale biogenic magnetite (BnM), synthesized by the Fe(III)-reducing bacterium Geobacter sulfurreducens, was tested for the potential to remediate alkaline Cr(VI) contaminated waters associated with chromite ore processing residue (COPR). The performance of this biomaterial, targeting aqueous Cr(VI) removal, was compared to a synthetic alternative, nano-scale zero valent iron (nZVI). Samples of highly contaminated alkaline groundwater and COPR solid waste were obtained from a contaminated site in Glasgow, UK. During batch reactivity tests, Cr(VI) removal from groundwater was inhibited by ∼25% (BnM) and ∼50% (nZVI) when compared to the treatment of less chemically complex model pH 12 Cr(VI) solutions. In both the model Cr(VI) solutions and contaminated groundwater experiments the surface of the nanoparticles became passivated, preventing complete coupling of their available electrons to Cr(VI) reduction. To investigate this process, the surfaces of the reacted samples were analyzed by TEM-EDX, XAS and XPS, confirming Cr(VI) reduction to the less soluble Cr(III) on the nanoparticle surface. In groundwater reacted samples the presence of Ca, Si and S was also noted on the surface of the nanoparticles, and is likely responsible for earlier onset of passivation. Treatment of the solid COPR material in contact with water, by addition of increasing weight % of the nanoparticles, resulted in a decrease in aqueous Cr(VI) concentrations to below detection limits, via the addition of ⩾5% w/w BnM or ⩾1% w/w nZVI. XANES analysis of the Cr K edge, showed that the % Cr(VI) in the COPR dropped from 26% to a minimum of 4-7% by the addition of 5% w/w BnM or 2% w/w nZVI, with higher additions unable to reduce the remaining Cr(VI). The treated materials exhibited minimal re-mobilization of soluble Cr(VI) by re-equilibration with atmospheric oxygen, with the bulk of the Cr remaining in the solid fraction. Both nanoparticles exhibited a considerable capacity for the remediation of COPR related Cr(VI) contamination, with the synthetic nZVI demonstrating greater reactivity than the BnM. However, the biosynthesized BnM was also capable of significant Cr(VI) reduction and demonstrated a greater efficiency for the coupling of its electrons towards Cr(VI) reduction than the nZVI.

18.
Environ Sci Technol ; 48(20): 11853-62, 2014 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-25236360

RESUMEN

Technetium incorporation into magnetite and its behavior during subsequent oxidation has been investigated at high pH to determine the technetium retention mechanism(s) on formation and oxidative perturbation of magnetite in systems relevant to radioactive waste disposal. Ferrihydrite was exposed to Tc(VII)(aq) containing cement leachates (pH 10.5-13.1), and crystallization of magnetite was induced via addition of Fe(II)aq. A combination of X-ray diffraction (XRD), chemical extraction, and X-ray absorption spectroscopy (XAS) techniques provided direct evidence that Tc(VII) was reduced and incorporated into the magnetite structure. Subsequent air oxidation of the magnetite particles for up to 152 days resulted in only limited remobilization of the incorporated Tc(IV). Analysis of both X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) data indicated that the Tc(IV) was predominantly incorporated into the magnetite octahedral site in all systems studied. On reoxidation in air, the incorporated Tc(IV) was recalcitrant to oxidative dissolution with less than 40% remobilization to solution despite significant oxidation of the magnetite to maghemite/goethite: All solid associated Tc remained as Tc(IV). The results of this study provide the first direct evidence for significant Tc(IV) incorporation into the magnetite structure and confirm that magnetite incorporated Tc(IV) is recalcitrant to oxidative dissolution. Immobilization of Tc(VII) by reduction and incorporation into magnetite at high pH and with significant stability upon reoxidation has clear and important implications for limiting technetium migration under conditions where magnetite is formed including in geological disposal of radioactive wastes.


Asunto(s)
Óxido Ferrosoférrico/química , Tecnecio/química , Adsorción , Precipitación Química , Compuestos Férricos/química , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Soluciones , Tecnecio/aislamiento & purificación , Espectroscopía de Absorción de Rayos X , Difracción de Rayos X
19.
Comp Med ; 74(2): 49-54, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38378179

RESUMEN

Experimental maxillofacial surgery is commonly performed in pigs; however, locoregional anesthesia of this area has not been described. This study evaluated the feasibility of a novel maxillary nerve block approach. In part I, cadavers were used to determine anatomic landmarks and assess maxillary nerve dye staining by using 0.03 mL kg-1 of a 1:10 mixture of commercial food dye and 0.5% bupivacaine. In part II, 10 additional pig cadavers underwent bilateral ultrasound-guided maxillary nerve blocks by using trans-infraorbital canal needle placement. The maxillary nerve was harvested and scored based on degree of staining (0 and 1, absent or incomplete staining; 2, staining; >1 cm circumferentially). Intracranial and intraconal spread of dye was evaluated. A Kruskal-Wallis test was used to compare infraorbital canal length estimated either externally via landmarks, internally via ultrasound, or actually measured after dissection. In 18 of 20 (90%) injections, successful staining (score = 2) of maxillary nerves was obtained for a nerve length of 2.4 ± 0.3 cm. Two of 20 cases (10%) had inadequate staining (score <2). At dissection of these 2 cases, the needle tip was observed to have collided with an unerupted tooth (third molar). No intracranial or intraconal spread of dye was observed. We detected no statistical differences between the estimated external, estimated internal, or actual dissection methods for measurement of infraorbital canal length (P = 0.3). Ultrasound-guided trans-infraorbital maxillary nerve block in pigs is a feasible technique, warranting further work to evaluate its in vivo efficacy and safety.


Asunto(s)
Estudios de Factibilidad , Nervio Maxilar , Bloqueo Nervioso , Animales , Nervio Maxilar/anatomía & histología , Porcinos , Bloqueo Nervioso/métodos , Bloqueo Nervioso/veterinaria , Cadáver , Ultrasonografía Intervencional/métodos , Bupivacaína/administración & dosificación , Anestésicos Locales/administración & dosificación , Órbita/anatomía & histología , Órbita/diagnóstico por imagen
20.
Am J Vet Res ; 85(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38479106

RESUMEN

OBJECTIVE: To compare the quality of recovery in horses emerging from general anesthesia with or without the assistance of a novel device (recovery-enhancing device [RED]) designed to minimize high-energy falls. ANIMALS: 20 mixed-breed horses, between July 1, 2023, and January 24, 2024. METHODS: A computer-controlled belay system designed to slow the acceleration of a horse during a fall was evaluated in this study. Horses were randomly assigned to 1 of 2 treatment groups: RED (belay, assisted) or FREE (unassisted). An inertia-measuring unit was fitted to all horses and data were live streamed and recorded onto a computer for further analysis. Recoveries were scored using the composite grading scale (CGS; 0 to 100) by 3 independent observers. Two additional unitless recovery scores (RS and RS'), based on accelerometry values (high accelerations, less desirable), were calculated for each recovery. All the recovery scores were compared between the 2 treatment groups. RESULTS: Composite grading scale scores were 26 ± 10 and 46 ± 13 in the RED and FREE groups, respectively (P = .001). The RS was 120 ± 79 and 198 ± 34 for the RED and FREE treatment groups, respectively (P = .015). The RS' was 32 (7 to 50) and 46 (28 to 44) for the RED and FREE treatment groups, respectively (P = .038). CLINICAL RELEVANCE: The RED improves the recovery scores compared with unassisted recoveries. This device may lead to a potential reduction in the number and severity of injuries in horses and personnel involved during the recovery period.


Asunto(s)
Periodo de Recuperación de la Anestesia , Anestesia General , Animales , Caballos , Anestesia General/veterinaria , Anestesia General/instrumentación , Femenino , Masculino , Accidentes por Caídas/prevención & control
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