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1.
Laryngoscope ; 134(3): 1457-1463, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37589298

RESUMEN

OBJECTIVE: Determine whether combination therapy with ganciclovir (GCV) and a Quercetin-P188 solution improves hearing outcomes in a murine cytomegalovirus (CMV) model. METHODS: BALB/c mice were infected with murine CMV on postnatal day 3 (p3). Quercetin was solubilized in saline using P188 (QP188). Treatment groups received either GCV, QP188, GCV and QP188, or P188 delivery vehicle BID at 12-hour intervals via intraperitoneal injection. All treatment groups were treated for 14 days starting at p3. Uninfected controls were treated with the combined regimen, saline or P188 delivery vehicle. Auditory thresholds were assessed using distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) testing at 4, 6, and 8 weeks of age. Temporal bones from separate CMV-infected groups were harvested at p10, and viral load was determined by quantitative polymerase chain reaction. RESULTS: CMV-infected mice receiving combination therapy GCV+QP188 demonstrated statistically significant lower ABR (p < 0.001) and DPOAE thresholds (p < 0.001) compared with mice treated with GCV monotherapy, QP188 monotherapy, and P188 delivery vehicle at 4, 6, and 8 weeks of age. GCV+QP188 combination therapy, GCV monotherapy, and QP188 monotherapy resulted in a nonsignificant reduction in mean viral titers compared to P188 monotherapy (p = 0.08). CONCLUSION: Combining GCV with the excipients quercetin and P188 effectively ameliorated CMV-induced sensorineural hearing loss in a murine model. This result may be partially explained by a reduction in viral titers in mouse temporal bones that correlate with in vitro studies demonstrating additive antiviral effect in cell culture. LEVEL OF EVIDENCE: NA Laryngoscope, 134:1457-1463, 2024.


Asunto(s)
Infecciones por Citomegalovirus , Sordera , Pérdida Auditiva , Animales , Ratones , Ganciclovir/farmacología , Ganciclovir/uso terapéutico , Citomegalovirus , Quercetina/farmacología , Quercetina/uso terapéutico , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/tratamiento farmacológico , Pérdida Auditiva/tratamiento farmacológico , Antivirales/farmacología , Antivirales/uso terapéutico
2.
Laryngoscope ; 134(1): 433-438, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37421238

RESUMEN

OBJECTIVE: Compare hearing outcomes utilizing standard, prolonged and delayed ganciclovir (GCV) therapy in a murine model of cytomegalovirus (CMV). METHODS: BALB/c mice were inoculated with mouse cytomegalovirus (mCMV) or saline via intracerebral injection on postnatal day 3 (p3). Intraperitoneal GCV or saline was administered at 12 h intervals for the duration of the standard (p3-p17), delayed (p30-p44), or prolonged treatment windows (p3-p31). Auditory thresholds were assessed using distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) testing at 4, 6, and 8 weeks of age. Blood and tissue samples were harvested from mice on p17 and p37 one hour after GCV administration, and their concentrations were assessed via liquid chromatography-mass spectrometry. RESULTS: A delayed course of GCV improved ABR but not DPOAE thresholds in mCMV-infected mice. A prolonged course of GCV did not provide better hearing thresholds than those administered standard treatment. The average GCV concentration in all 17-day-old mice tissue was significantly higher than those in older 37-day-old mice. CONCLUSION: Delayed GCV treatment provided a hearing benefit on ABR over untreated mCMV infected mice. Prolonged CGV administration showed no benefit compared to a shorter duration GCV treatment. GCV drug concentrations both systemically and in the cochlea are much lower in older mice. These results have potential implications for the clinical management of cCMV infected children. LEVEL OF EVIDENCE: NA Laryngoscope, 134:433-438, 2024.


Asunto(s)
Infecciones por Citomegalovirus , Muromegalovirus , Humanos , Niño , Animales , Ratones , Anciano , Ganciclovir/uso terapéutico , Infecciones por Citomegalovirus/tratamiento farmacológico , Citomegalovirus , Emisiones Otoacústicas Espontáneas , Ratones Endogámicos BALB C , Antivirales/uso terapéutico
3.
Am J Otolaryngol ; 45(1): 104024, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37647777

RESUMEN

OBJECTIVE: To evaluate the efficacy of tympanomastoidectomy versus parenteral antibiotic therapy for otorrhea as a result of chronic suppurative otitis media (CSOM) without cholesteatoma in the pediatric population. METHODS: A retrospective review of 221 patients treated for otorrhea at a tertiary academic pediatric hospital was performed to evaluate the impact of tympanomastoidectomy versus parenteral antibiotic therapy on resolution of otorrhea. Inclusion criteria were age 0-18 years, prior treatment with otic and/or oral antibiotic, prior history of tympanostomy tube placement for recurrent otitis media, history of otorrhea, treatment with tympanomastoidectomy or parenteral antibiotic therapy, and follow-up of at least 1 month after intervention. Time to resolution was compared between the two modalities adjusting for age, bilateral ear disease status, and comorbidities using a Cox proportional hazard model. RESULTS: Eighty-three ears from 58 children met the inclusion criteria. Ears that initially underwent tympanomastoidectomy had a significantly shorter time to resolution of symptoms (median time to resolution) 9 months (95 % confidence interval CI: 6.2-14.8) vs. 48.5 months (95 % lower CI 9.4, p = 0.006). On multivariate analysis, however, only bilateral ear disease status was independently associated with time to resolution of symptoms (hazard ratio 0.4, 95 % CI 0.2-0.9, p = 0.03). There was no statistically significant difference in the rate of treatment-related complications when comparing tympanomastoidectomy to parenteral antibiotic therapy (p = 0.37). CONCLUSION: When adjusting for age, bilateral ear disease status, and comorbidities, there does not appear to be a significant difference in time to resolution of symptoms when comparing parenteral antibiotic therapy to tympanomastoidectomy. An informed discussion regarding risks and benefits of each approach should be employed when deciding on the next step in management for patients with CSOM who have failed more conservative therapies.


Asunto(s)
Otitis Media Supurativa , Otitis Media , Niño , Humanos , Recién Nacido , Lactante , Preescolar , Adolescente , Antibacterianos/uso terapéutico , Ventilación del Oído Medio/efectos adversos , Otitis Media Supurativa/complicaciones , Otitis Media Supurativa/tratamiento farmacológico , Otitis Media Supurativa/cirugía , Otitis Media/complicaciones , Quimioterapia Combinada , Resultado del Tratamiento
4.
Inorg Chem ; 62(24): 9589-9601, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37285469

RESUMEN

Resonant two-photon ionization experiments have been conducted to probe the bond dissociation energy (BDE) of the lanthanide-carbon bond, allowing the BDEs of CeC, PrC, NdC, LuC, and Tm-C2 to be measured to high precision. Values of D0(CeC) = 4.893(3) eV, D0(PrC) = 4.052(3) eV, D0(NdC) = 3.596(3) eV, D0(LuC) = 3.685(4) eV, and D0(Tm-C2) = 4.797(6) eV are obtained. Additionally, the adiabatic ionization energy of LuC was measured, giving IE(LuC) = 7.05(3) eV. The electronic structure of these species, along with the previously measured LaC, has been further investigated using quantum chemical calculations. Despite LaC, CeC, PrC, and NdC having ground electronic configurations that differ only in the number of 4f electrons present and have virtually identical bond orders, bond lengths, fundamental stretching frequencies, and metallic oxidation states, a peculiar 1.30 eV range in bond dissociation energies exists for these molecules. A natural bond orbital analysis shows that the metal atoms in these molecules have a natural charge of +1 with a 5d2 4fn 6s0 configuration while the carbon atom has a natural charge of -1 and a 2p3 configuration. The diabatic bond dissociation energies, calculated with respect to the lowest energy level of this separated ion configuration, show a greatly reduced energy range of 0.32 eV, with the diabatic BDE decreasing as the amount of 4f character in the σ-bond increases. Thus, the wide range of measured BDEs for these molecules is a consequence of the variation in atomic promotion energies at the separated ion limit. TmC2 has a smaller BDE than the other LnC2 molecules, due to the tiny amount of 5d participation in the valence molecular orbitals.

5.
Otolaryngol Head Neck Surg ; 169(6): 1491-1498, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37313962

RESUMEN

OBJECTIVE: To determine whether hamster and human tissues generate similar amounts of aerosolized particles using common otolaryngology surgical techniques. STUDY DESIGN: Quantitative experimental research. STUDY SETTING: University research laboratory. METHODS: Drilling, electrocautery, and coblation were performed on human and hamster tissues. Particle size and concentration were measured during the surgical procedures using a scanning mobility particle sizer and an aerosol particle sizer (SMPS-APS) and GRIMM aerosol particle spectrometer. RESULTS: SMPS-APS and GRIMM measurements detected at least 2-fold increases in aerosol concentrations compared to baseline during all procedures. Procedures performed on human and hamster tissues produced similar trends and order of magnitude of aerosol concentrations. Generally, hamster tissues produced higher aerosol concentrations compared to human tissues, and some of these differences were statistically significant. Mean particle sizes for all procedures were small (<200 nm), although statistically significant differences in particle size were identified between human and hamster tissues during coblation and drilling. CONCLUSION: Aerosol-generating procedures performed on human and hamster tissue produce similar trends in aerosol particle concentrations and sizes, although we observed some differences between the 2 tissue types. Further studies should be performed to understand the clinical significance of these differences.


Asunto(s)
Nariz , Otolaringología , Animales , Humanos , Tamaño de la Partícula , Aerosoles
6.
Otolaryngol Head Neck Surg ; 169(3): 679-686, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36884018

RESUMEN

OBJECTIVE: Determine the detection rate from an expanded targeted early cytomegalovirus (CMV) testing program implemented from a large healthcare system (Intermountain Healthcare, IHC). STUDY DESIGN: Retrospective review. SETTING: Tertiary medical center. METHODS: An electronic system was modified to include indications for testing whenever a provider placed an order for CMV testing. A retrospective analysis of this database was performed. RESULTS: From March 1, 2021 to August 31, 2022, there were 3450 (8.8%) patients who underwent CMV testing out of 39,245 total live births within the IHC system. Since the formal implementation of this program in 2019, annual CMV testing has increased almost 10-fold: 2668 CMV tests were performed in 2021 compared to 289 CMV tests in 2015. The most frequent indication for congenital CMV (cCMV) testing was small for gestational age (SGA) (68.2%), followed by macrocephaly (13.5%), an abnormal hearing test (5.0%), and microcephaly (4.4%). Fourteen cCMV-infected infants were diagnosed all of them meeting the criteria for symptomatic cCMV. The most common indication resulting in a positive diagnosis was those who presented with SGA (n = 10 patients). The positivity rate would result in a prevalence of 35.7 symptomatic cCMV cases diagnosed per 100,000 live births, numbers comparable to those expected for universal cCMV screening. CONCLUSION: An expanded targeted early cCMV testing program may improve detection rates of symptomatic cCMV cases and should be considered as a feasible alternative approach to universal or hearing-targeted early CMV testing.


Asunto(s)
Infecciones por Citomegalovirus , Pérdida Auditiva Sensorineural , Enfermedades del Recién Nacido , Recién Nacido , Lactante , Humanos , Citomegalovirus , Estudios Retrospectivos , Tamizaje Neonatal/métodos , Infecciones por Citomegalovirus/diagnóstico , Pérdida Auditiva Sensorineural/diagnóstico
7.
J Am Chem Soc ; 144(17): 7557-7561, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35439416

RESUMEN

The bond dissociation energies of early transition metal diborides (M-B2, M = Sc, Ti, V, Y, Mo) have been measured by observation of the sharp onset of predissociation in a highly congested spectrum. Density functional and CCSD(T) ab initio calculations, extrapolated to the complete basis set limit, have been used to examine the electronic structure of these species. The computations demonstrate the formation of bonding orbitals between the metal d orbitals and the 1πu bonding orbitals of B2, leading to the transfer of metallic electron density into the bonding 1πu orbitals, strengthening both the M-B and B-B bonds in the molecule. This runs counter to most metal-ligand π interactions, where electron density is generally transferred into π antibonding orbitals of the ligand.


Asunto(s)
Elementos de Transición , Ligandos , Metales/química , Elementos de Transición/química
8.
Am J Infect Control ; 50(6): 602-607, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35301061

RESUMEN

OBJECTIVE: To understand whether perioperative SARS-CoV-2 infection increases risk of pulmonary complications in children. METHODS: A retrospective cohort study of children who underwent surgery with perioperative SARS-CoV-2 infection at a children's hospital from March 1, 2020, to June 30, 2021. Uninfected, age-matched control patients who underwent the same procedure as infected patients over the past ten years were included in the study in a 3:1 ratio to infected patients. Primary outcomes were 7- and 30-day mortality. Secondary outcomes were development of pulmonary complications, readmission, length of hospital or ICU stay, and oxygen administration in post-anesthesia care unit (PACU). RESULTS: Our study included 73 patients who underwent surgery with perioperative diagnosis of SARS-CoV-2, and 218 control patient undergoing similar procedures. One total mortality event was observed within 7 days in an uninfected control patient, and none occurred in infected patients. Perioperative SARS-CoV-2 infection was associated with increased risk for pulmonary complications in univariate analysis. Infection was not associated with any of our other secondary outcomes. Symptomatic SARS-CoV-2 infection and timing of diagnosis was not associated with development of pulmonary complications among infected patients. CONCLUSIONS: Children with perioperative SARS-CoV-2 infection may be at increased risk for development of pulmonary complications. Larger studies should be performed to confirm our results.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Prueba de COVID-19 , Niño , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
9.
Hear Res ; 417: 108454, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35131579

RESUMEN

Congenital cytomegalovirus (CMV) infection is a significant cause of neonatal hearing loss. However, at the cochlear level, the anatomical lesions and pathophysiological mechanisms that underlie hearing loss are still not clearly understood. In murine models of CMV infection, we have observed early damage to the capillary networks in stria vascularis, as well as hearing loss manifested in ABR threshold elevations. Our experimental hypothesis is that strial damage causes a reduced endocochlear potential (EP) resulting in impaired haircell activation and consequent hearing loss. We have studied strial damage, EP, and ABR threshold elevations in two mouse models (BALB/c and C57BL6 strains) infected with murine CMV. Neonatal (P3) pups were inoculated with murine CMV (2µl of 200pfu) by intra cerebral injection. Control mice were saline injected. At 6 weeks, ABR thresholds to tonal stimuli at 8, 16 and 32 kHz were determined for each ear. At 8 weeks a sub-group of treated and control animals was prepared for study of cochlear capillary networks using scanning electron microscopy of corrosion cast specimens. In a second group, at 8 weeks, EP measurements from both cochleas were made. We report that in both mouse strains, CMV infection caused capillary loss in the stria vascularis, initially at the cochlear apex, and extending to lower cochlear turns in some subjects. After CMV infection, in both BALB/c and C57BL6 mice, reduced EPs and ABR threshold elevations were observed, and there was a within-animal correlation between loss of EP and ABR threshold elevations across the sound frequencies tested. These results suggest that CMV induced damage to stria vascularis results in EP reduction that is correlated with ABR threshold elevations. Extrapolating to the human condition, we suggest that strial damage and its physiological consequences may contribute to the initial hearing loss in congenital CMV infection. The early involvement of cochlear capillary damage may encourage a focus on therapeutic interventions that can prevent vascular damage, or subsequently promote vascular healing or angiogenesis.


Asunto(s)
Infecciones por Citomegalovirus , Sordera , Pérdida Auditiva , Animales , Cóclea , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/patología , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Estría Vascular/patología
10.
Cells ; 10(12)2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34944105

RESUMEN

Emerging evidence indicates that perinatal infection and inflammation can influence the developing immune system and may ultimately affect long-term health and disease outcomes in offspring by perturbing tissue and immune homeostasis. We posit that perinatal inflammation influences immune outcomes in offspring by perturbing (1) the development and function of fetal-derived immune cells that regulate tissue development and homeostasis, and (2) the establishment and function of developing hematopoietic stem cells (HSCs) that continually generate immune cells across the lifespan. To disentangle the complexities of these interlinked systems, we propose the cochlea as an ideal model tissue to investigate how perinatal infection affects immune, tissue, and stem cell development. The cochlea contains complex tissue architecture and a rich immune milieu that is established during early life. A wide range of congenital infections cause cochlea dysfunction and sensorineural hearing loss (SNHL), likely attributable to early life inflammation. Furthermore, we show that both immune cells and bone marrow hematopoietic progenitors can be simultaneously analyzed within neonatal cochlear samples. Future work investigating the pathogenesis of SNHL in the context of congenital infection will therefore provide critical information on how perinatal inflammation drives disease susceptibility in offspring.


Asunto(s)
Cóclea/patología , Hematopoyesis , Sistema Inmunológico/crecimiento & desarrollo , Inflamación/patología , Animales , Feto/inmunología , Pérdida Auditiva Sensorineural/inmunología , Humanos
11.
Orphanet J Rare Dis ; 16(1): 357, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34376220

RESUMEN

Ehlers-Danlos Syndrome (EDS) are a heterogeneous group of genetic connective tissue disorders, and typically manifests as weak joints that subluxate/dislocate, stretchy and/or fragile skin, organ/systems dysfunction, and significant widespread pain. Historically, this syndrome has been poorly understood and often overlooked. As a result, people living with EDS had difficulty obtaining an accurate diagnosis and appropriate treatment, leading to untold personal suffering as well as ineffective health care utilization. The GoodHope EDS clinic addresses systemic gaps in the diagnosis and treatment of EDS. This paper describes a leap forward-from lack of awareness, diagnosis, and treatment-to expert care that is tailored to meet the specific needs of patients with EDS. The GoodHope EDS clinic consists of experts from various medical specialties who work together to provide comprehensive care that addresses the multi-systemic nature of the syndrome. In addition, EDS-specific self-management programs have been developed that draw on exercise science, rehabilitation, and health psychology to improve physical and psychosocial wellbeing and overall quality of life. Embedded into the program are research initiatives to shed light on the clinical presentation, underlying mechanisms of pathophysiology, and syndrome management. We also lead regular educational activities for community health care providers to increase awareness and competence in the interprofessional management of EDS beyond our doors and throughout the province and country.


Asunto(s)
Enfermedades del Tejido Conjuntivo , Síndrome de Ehlers-Danlos , Inestabilidad de la Articulación , Tejido Conectivo , Enfermedades del Tejido Conjuntivo/diagnóstico , Síndrome de Ehlers-Danlos/diagnóstico , Hospitales Generales , Humanos , Calidad de Vida
12.
Nat Protoc ; 16(6): 2765-2787, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33953393

RESUMEN

Early prediction of patient outcomes is important for targeting preventive care. This protocol describes a practical workflow for developing deep-learning risk models that can predict various clinical and operational outcomes from structured electronic health record (EHR) data. The protocol comprises five main stages: formal problem definition, data pre-processing, architecture selection, calibration and uncertainty, and generalizability evaluation. We have applied the workflow to four endpoints (acute kidney injury, mortality, length of stay and 30-day hospital readmission). The workflow can enable continuous (e.g., triggered every 6 h) and static (e.g., triggered at 24 h after admission) predictions. We also provide an open-source codebase that illustrates some key principles in EHR modeling. This protocol can be used by interdisciplinary teams with programming and clinical expertise to build deep-learning prediction models with alternate data sources and prediction tasks.


Asunto(s)
Aprendizaje Profundo , Registros Electrónicos de Salud , Proyectos de Investigación , Medición de Riesgo/métodos , Humanos , Programas Informáticos , Flujo de Trabajo
13.
J Phys Chem A ; 125(20): 4420-4434, 2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34003640

RESUMEN

The predissociation thresholds of the early transition metal boride diatomics (MB, M = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta, W) have been measured using resonant two-photon ionization (R2PI) spectroscopy, allowing for a precise assignment of the bond dissociation energy (BDE). No previous experimental measurements of the BDE exist in the literature for these species. Owing to the high density of electronic states arising from the ground and low-lying separated atom limits in these open d-subshell species, a congested spectrum of vibronic transitions is observed as the energy of the ground separated atom limit is approached. Nonadiabatic and spin-orbit interactions among these states, however, provide a pathway for rapid predissociation as soon as the ground separated atom limit is reached, leading to a sharp decrease in signal to background levels when this limit is reached. Accordingly, the BDEs of the early transition metal borides have been assigned as D0(ScB) 1.72(6) eV, D0(TiB) 1.956(16) eV, D0(VB) 2.150(16) eV, D0(YB) 2.057(3) eV, D0(ZrB) 2.573(5) eV, D0(NbB) 2.989(12) eV, D0(LaB) 2.086(18) eV, D0(HfB) 2.593(3) eV, D0(TaB) 2.700(3) eV, and D0(WB) 2.730(4) eV. Additional insight into the chemical bonding and electronic structures of these species has been achieved by quantum chemical calculations.

14.
Otolaryngol Head Neck Surg ; 164(3): 547-555, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32928037

RESUMEN

OBJECTIVES: To determine whether common otolaryngology procedures generate viable aerosolized virus through a murine cytomegalovirus (mCMV) model for infection. STUDY DESIGN: mCMV model of infection. SETTING: University of Utah laboratory. METHODS: Three-day-old BALB/c mice were inoculated with mCMV or saline. Five days later, each mouse underwent drilling, microdebrider, coblation, and electrocautery procedures. Particle size distribution and PM2.5 (particulate matter <2.5 µm) concentration were determined with a scanning mobility particle sizer and an aerosol particle sizer in the range of 15 nm to 32 µm. Aerosolized samples from these procedures were collected with an Aerosol Devices BioSpot sampler for viral titer based on polymerase chain reaction and for viable virus through viral culture. RESULTS: As compared with the background aerosol concentrations, coblation and electrocautery showed statistically significant increases in airborne aerosols (Tukey-adjusted P value <.040), while microdebrider and drilling at 30,000 rpm did not (.870 < Tukey-adjusted P value < .930). We identified viral DNA in samples from coblation and drilling procedures, although we did not identify viable viruses in aerosol samples from any of the 4 procedures. CONCLUSION: Coblation and electrocautery procedures generate >100-fold increases in aerosol concentrations over background; only coblation and drilling produce aerosolized viral DNA. The high concentration of aerosols from coblation and electrocautery suggests the need for appropriate safeguards against particle exposure to health care workers. The presence of viral DNA from drilling and coblation procedures warrants the need for appropriate protection against droplet and aerosol exposure.


Asunto(s)
Microbiología del Aire , COVID-19 , Muromegalovirus/aislamiento & purificación , Procedimientos Quirúrgicos Otorrinolaringológicos , Aerosoles , Animales , Ratones , Ratones Endogámicos BALB C
15.
J Chem Phys ; 153(7): 074303, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32828096

RESUMEN

Through the use of resonant two-photon ionization spectroscopy, sharp predissociation thresholds have been identified in the spectra of CrO, MoO, RuO, and RhO. Similar thresholds have previously been used to measure the bond dissociation energies (BDEs) of many molecules that have a high density of vibronic states at the ground separated atom limit. A high density of states allows precise measurement of the BDE by facilitating prompt dissociation to ground state atoms when the BDE is exceeded. However, the number of states required for prompt predissociation at the thermochemical threshold is not well defined and undoubtedly varies from molecule to molecule. The ground separated atom limit generates 315 states for RuO, 252 states for RhO, and 63 states for CrO and MoO. Although comparatively few states derive from this limit for CrO and MoO, the observation of sharp predissociation thresholds for all four molecules nevertheless allows BDEs to be assigned as 4.863(3) eV (RuO), 4.121(3) eV (RhO), 4.649(5) eV (CrO), and 5.414(19) eV (MoO). Thermochemical cycles are used to derive the enthalpies of formation of the gaseous metal oxides and to obtain IE(RuO) = 8.41(5) eV, IE(RhO) = 8.56(6) eV, D0(Ru-O-) = 4.24(2) eV, D0(Cr-O-) = 4.409(8) eV, and D0(Mo-O-) = 5.243(20) eV. The mechanisms leading to prompt predissociation at threshold in the cases of CrO and MoO are discussed. Also presented is a discussion of the bonding trends for the transition metal oxides, which are compared to the previously measured transition metal sulfides.

16.
J Chem Phys ; 153(2): 024303, 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32668947

RESUMEN

The predissociation threshold of VO has been measured using resonant three-photon ionization (R3PI) spectroscopy. Given the high density of electronic states in the molecule, it is argued that the molecule dissociates rapidly as soon as the thermochemical bond dissociation energy (BDE) is exceeded, allowing the measured predissociation threshold to be assigned as the BDE. This is the first time a BDE has been measured using the R3PI method. The first photon is provided by an optical parametric oscillator (OPO) laser that promotes VO into a high-energy, discrete vibronic state. A tunable dye laser then excites the molecule further to a resonant state close to the dissociation limit where there is a quasi-continuum of states. A second photon from the same dye laser pulse ionizes the molecule, generating VO+ ions. The dye laser is then scanned to higher energies, and when the energy of one OPO photon plus one dye photon exceeds the BDE, the molecule dissociates before another dye photon can be absorbed to induce ionization. The combined photon energy at the sharp drop in the ion signal is assigned as the BDE. The experiment has been repeated using four different intermediate states, all yielding the same BDE, D0(VO) = 6.545(2) eV. Using thermochemical cycles, a revised value for the BDE of cationic VO is obtained, D0(V+-O) = 6.053(2) eV. The 0 K enthalpy of formation for VO(g) is also derived as ΔfH0K 0VO(g) = 128.6(1.0) kJ mol-1. Previous spectroscopic and thermochemical studies of VO are reviewed.

17.
Int J Pediatr Otorhinolaryngol ; 133: 110007, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32208178

RESUMEN

OBJECTIVE: To determine whether a community engagement approach can provide feedback for implementation of valuable measures to improve the outcome of a clinical trial. METHODS: Review of the results from a Community Engagement Studio (CE Studio) for the ValEAR trial: an NIH-funded, multi-institutional study designed to research the efficacy of valganciclovir in the treatment of congenital cytomegalovirus (cCMV)-induced hearing loss. Participants were given information about the trial then asked a series of questions to assess their input on the merits or weaknesses affecting their participation in the trial. RESULTS: Thirteen parents whose children have congenital CMV infection were recruited for the CE Studio. The overall theme from the responses was a desire to advance the field but a need to clearly understand the risks and benefits of participation. Many requested more educational resources, more printed materials, or greater access to researchers if questions arose. Many welcomed having patient stories and information displayed in a dedicated website or through social media. CONCLUSION: This community engagement approach provided useful feedback from families similar to those expected to be potential enrollees in the CMV ValEAR trial. In response to parental comments, two educational videos were created: one on the general topic of cCMV and the other specific to the CMV ValEAR trial. Researchers who wish to optimize their clinical trial's success should consider incorporating a CE Studio into their study design.


Asunto(s)
Participación del Paciente , Selección de Paciente , Antivirales/uso terapéutico , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/congénito , Infecciones por Citomegalovirus/tratamiento farmacológico , Retroalimentación , Femenino , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Pérdida Auditiva Sensorineural/virología , Humanos , Masculino , Estudios Multicéntricos como Asunto , Padres , Educación del Paciente como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Participación de los Interesados , Valganciclovir/uso terapéutico
18.
J Chem Phys ; 152(19): 194307, 2020 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-33687227

RESUMEN

The early transition metal diatomic sulfides, MS, M = Sc, Y, Ti, Zr, Hf, Nb, and Ta, have been investigated using resonant two-photon ionization spectroscopy in the vicinity of their bond dissociation energies (BDEs). Due to the high density of vibronic states in this energy range, the molecular spectra appear quasicontinuous, and when the excitation energy exceeds the ground separated atom limit, excited state decay by dissociation becomes possible. The dissociation process typically occurs so rapidly that the molecule falls apart before a second photon can be absorbed to ionize the species, leading to a sharp drop in ion signal, which is identified as the 0 K BDE. The observed predissociation thresholds yield BDEs of 4.852(10) eV (ScS), 5.391(3) eV (YS), 4.690(4) eV (TiS), 5.660(4) eV (ZrS), 5.780(20) eV (HfS), 5.572(3) eV (NbS), and 5.542(3) eV (TaS). Utilizing thermochemical cycles, the enthalpies of formation, ΔfH0K o(g), of 182.7(4.3) kJ mol-1 (ScS), 178.3(4.2) kJ mol-1 (YS), 293.1(16.7) kJ mol-1 (TiS), 337.3(8.4) kJ mol-1 (ZrS), 335.0(6.6) kJ mol-1 (HfS), 467.0(8.0) kJ mol-1 (NbS), and 521.5(2.1) kJ mol-1 (TaS) are obtained. Another thermochemical cycle has been used to combine the previously measured M+-S BDEs with the M-S BDEs and atomic ionization energies to obtain the MS ionization energies of 6.44(5) eV (ScS), 6.12(8) eV (YS), 6.78(7) eV (TiS), 6.60(10) eV (ZrS), and 6.88(9) eV (NbS). Using this same cycle, we obtain D0(Hf+-S) = 4.926(20) eV. The bonding trends of the early transition metal sulfides, along with the corresponding selenides, are discussed.

19.
Nature ; 572(7767): 116-119, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31367026

RESUMEN

The early prediction of deterioration could have an important role in supporting healthcare professionals, as an estimated 11% of deaths in hospital follow a failure to promptly recognize and treat deteriorating patients1. To achieve this goal requires predictions of patient risk that are continuously updated and accurate, and delivered at an individual level with sufficient context and enough time to act. Here we develop a deep learning approach for the continuous risk prediction of future deterioration in patients, building on recent work that models adverse events from electronic health records2-17 and using acute kidney injury-a common and potentially life-threatening condition18-as an exemplar. Our model was developed on a large, longitudinal dataset of electronic health records that cover diverse clinical environments, comprising 703,782 adult patients across 172 inpatient and 1,062 outpatient sites. Our model predicts 55.8% of all inpatient episodes of acute kidney injury, and 90.2% of all acute kidney injuries that required subsequent administration of dialysis, with a lead time of up to 48 h and a ratio of 2 false alerts for every true alert. In addition to predicting future acute kidney injury, our model provides confidence assessments and a list of the clinical features that are most salient to each prediction, alongside predicted future trajectories for clinically relevant blood tests9. Although the recognition and prompt treatment of acute kidney injury is known to be challenging, our approach may offer opportunities for identifying patients at risk within a time window that enables early treatment.


Asunto(s)
Lesión Renal Aguda/diagnóstico , Técnicas de Laboratorio Clínico/métodos , Lesión Renal Aguda/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Simulación por Computador , Conjuntos de Datos como Asunto , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Curva ROC , Medición de Riesgo , Incertidumbre , Adulto Joven
20.
J Am Heart Assoc ; 4(12)2015 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-26656858

RESUMEN

BACKGROUND: Acute kidney injury (AKI) occurs frequently after cardiac catheterization and percutaneous coronary intervention. Although a clinical risk model exists for percutaneous coronary intervention, no models exist for both procedures, nor do existing models account for risk factors prior to the index admission. We aimed to develop such a model for use in prospective automated surveillance programs in the Veterans Health Administration. METHODS AND RESULTS: We collected data on all patients undergoing cardiac catheterization or percutaneous coronary intervention in the Veterans Health Administration from January 01, 2009 to September 30, 2013, excluding patients with chronic dialysis, end-stage renal disease, renal transplant, and missing pre- and postprocedural creatinine measurement. We used 4 AKI definitions in model development and included risk factors from up to 1 year prior to the procedure and at presentation. We developed our prediction models for postprocedural AKI using the least absolute shrinkage and selection operator (LASSO) and internally validated using bootstrapping. We developed models using 115 633 angiogram procedures and externally validated using 27 905 procedures from a New England cohort. Models had cross-validated C-statistics of 0.74 (95% CI: 0.74-0.75) for AKI, 0.83 (95% CI: 0.82-0.84) for AKIN2, 0.74 (95% CI: 0.74-0.75) for contrast-induced nephropathy, and 0.89 (95% CI: 0.87-0.90) for dialysis. CONCLUSIONS: We developed a robust, externally validated clinical prediction model for AKI following cardiac catheterization or percutaneous coronary intervention to automatically identify high-risk patients before and immediately after a procedure in the Veterans Health Administration. Work is ongoing to incorporate these models into routine clinical practice.


Asunto(s)
Lesión Renal Aguda/etiología , Angiografía Coronaria/efectos adversos , Técnicas de Apoyo para la Decisión , United States Department of Veterans Affairs/estadística & datos numéricos , Anciano , Cateterismo Cardíaco/efectos adversos , Femenino , Humanos , Modelos Logísticos , Masculino , Intervención Coronaria Percutánea/efectos adversos , Reproducibilidad de los Resultados , Factores de Riesgo , Estados Unidos/epidemiología
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