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1.
N Engl J Med ; 387(2): 148-159, 2022 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-35830641

RESUMEN

BACKGROUND: Neonatal hypoxic-ischemic encephalopathy is an important cause of death as well as long-term disability in survivors. Erythropoietin has been hypothesized to have neuroprotective effects in infants with hypoxic-ischemic encephalopathy, but its effects on neurodevelopmental outcomes when given in conjunction with therapeutic hypothermia are unknown. METHODS: In a multicenter, double-blind, randomized, placebo-controlled trial, we assigned 501 infants born at 36 weeks or more of gestation with moderate or severe hypoxic-ischemic encephalopathy to receive erythropoietin or placebo, in conjunction with standard therapeutic hypothermia. Erythropoietin (1000 U per kilogram of body weight) or saline placebo was administered intravenously within 26 hours after birth, as well as at 2, 3, 4, and 7 days of age. The primary outcome was death or neurodevelopmental impairment at 22 to 36 months of age. Neurodevelopmental impairment was defined as cerebral palsy, a Gross Motor Function Classification System level of at least 1 (on a scale of 0 [normal] to 5 [most impaired]), or a cognitive score of less than 90 (which corresponds to 0.67 SD below the mean, with higher scores indicating better performance) on the Bayley Scales of Infant and Toddler Development, third edition. RESULTS: Of 500 infants in the modified intention-to-treat analysis, 257 received erythropoietin and 243 received placebo. The incidence of death or neurodevelopmental impairment was 52.5% in the erythropoietin group and 49.5% in the placebo group (relative risk, 1.03; 95% confidence interval [CI], 0.86 to 1.24; P = 0.74). The mean number of serious adverse events per child was higher in the erythropoietin group than in the placebo group (0.86 vs. 0.67; relative risk, 1.26; 95% CI, 1.01 to 1.57). CONCLUSIONS: The administration of erythropoietin to newborns undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy did not result in a lower risk of death or neurodevelopmental impairment than placebo and was associated with a higher rate of serious adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT02811263.).


Asunto(s)
Eritropoyetina , Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Fármacos Neuroprotectores , Administración Intravenosa , Parálisis Cerebral/etiología , Método Doble Ciego , Eritropoyetina/administración & dosificación , Eritropoyetina/efectos adversos , Eritropoyetina/uso terapéutico , Humanos , Hipotermia Inducida/métodos , Hipoxia-Isquemia Encefálica/complicaciones , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/terapia , Lactante , Recién Nacido , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/efectos adversos , Fármacos Neuroprotectores/uso terapéutico
2.
J Am Chem Soc ; 146(22): 15219-15229, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38775440

RESUMEN

Unraveling the catalyst surface structure and behavior during reactions is essential for both mechanistic understanding and performance optimization. Here we report a phenomenon of facet-dependent surface restructuring intrinsic to ß-Ni(OH)2 catalysts during oxygen evolution reaction (OER), discovered by the correlative ex situ and operando characterization. The ex situ study after OER reveals ß-Ni(OH)2 restructuring at the edge facets to form nanoporous Ni1-xO, which is Ni deficient containing Ni3+ species. Operando liquid transmission electron microscopy (TEM) and Raman spectroscopy further identify the active role of the intermediate ß-NiOOH phase in both the OER catalysis and Ni1-xO formation, pinpointing the complete surface restructuring pathway. Such surface restructuring is shown to effectively increase the exposed active sites, accelerate Ni oxidation kinetics, and optimize *OH intermediate bonding energy toward fast OER kinetics, which leads to an extraordinary activity enhancement of ∼16-fold. Facilitated by such a self-activation process, the specially prepared ß-Ni(OH)2 with larger edge facets exhibits a 470-fold current enhancement than that of the benchmark IrO2, demonstrating a promising way to optimize metal-(oxy)hydroxide-based catalysts.

3.
J Pediatr ; 268: 113933, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38309524

RESUMEN

OBJECTIVE: To compare the short- and long-term outcomes of infants with hypoxic-ischemic encephalopathy (HIE) treated with whole-body therapeutic hypothermia (TH), monitored by esophageal vs rectal temperature. STUDY DESIGN: We conducted a secondary analysis of the multicenter High-Dose Erythropoietin for Asphyxia and Encephalopathy (HEAL) trial. All infants had moderate or severe HIE and were treated with whole-body TH. The primary outcome was death or neurodevelopmental impairment (NDI) at 22-36 months of age. Secondary outcomes included seizures, evidence of brain injury on magnetic resonance imaging, and complications of hypothermia. Logistic regression was used with adjustment for disease severity and site as clustering variable because cooling modality differed by site. RESULTS: Of the 500 infants who underwent TH, 294 (59%) and 206 (41%) had esophageal and rectal temperature monitoring, respectively. There were no differences in death or NDI, seizures, or evidence of injury on magnetic resonance imaging between the 2 groups. Infants treated with TH and rectal temperature monitoring had lower odds of overcooling (OR 0.52, 95% CI 0.34-0.80) and lower odds of hypotension (OR 0.57, 95% CI 0.39-0.84) compared with those with esophageal temperature monitoring. CONCLUSIONS: Although infants undergoing TH with esophageal monitoring were more likely to experience overcooling and hypotension, the rate of death or NDI was similar whether esophageal monitoring or rectal temperature monitoring was used. Further studies are needed to investigate whether esophageal temperature monitoring during TH is associated with an increased risk of overcooling and hypotension.


Asunto(s)
Temperatura Corporal , Esófago , Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Recto , Humanos , Hipotermia Inducida/métodos , Hipoxia-Isquemia Encefálica/terapia , Masculino , Femenino , Recién Nacido , Lactante , Esófago/diagnóstico por imagen , Resultado del Tratamiento , Monitoreo Fisiológico/métodos , Imagen por Resonancia Magnética , Preescolar
4.
J Pediatr ; 266: 113853, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38006967

RESUMEN

OBJECTIVE: To determine if time to reaching target temperature (TT) is associated with death or neurodevelopmental impairment (NDI) at 2 years of age in infants with hypoxic-ischemic encephalopathy (HIE). STUDY DESIGN: Newborn infants ≥36 weeks of gestation diagnosed with moderate or severe HIE and treated with therapeutic hypothermia were stratified based on time at which TT was reached, defined as early (ie, ≤4 hours of age) or late (>4 hours of age). Primary outcomes were death or NDI. Secondary outcomes included neurodevelopmental assessment with Bayley Scales of Infant and Toddler Development, third edition (BSID-III) at age 2. RESULTS: Among 500 infants, the median time to reaching TT was 4.3 hours (IWR, 3.2-5.7 hours). Infants in early TT group (n = 211 [42%]) compared with the late TT group (n = 289 [58%]) were more likely to be inborn (23% vs 13%; P < .001) and have severe HIE (28% vs 19%; P = .03). The early and late TT groups did not differ in the primary outcome of death or any NDI (adjusted RR, 1.05; 95% CI, 0.85-0.30; P = .62). Among survivors, neurodevelopmental outcomes did not differ significantly in the 2 groups (adjusted mean difference in Bayley Scales of Infant Development-III scores: cognitive, -2.8 [95% CI, -6.1 to 0.5], language -3.3 [95% CI, -7.4 to 0.8], and motor -3.5 [95% CI, -7.3 to 0.3]). CONCLUSIONS: In infants with HIE, time to reach TT is not independently associated with risk of death or NDI at age 2 years. Among survivors, developmental outcomes are similar between those who reached TT at <4 and ≥4 hours of age. TRIAL REGISTRATION: High-dose Erythropoietin for Asphyxia and Encephalopathy (HEAL); NCT02811263; https://beta. CLINICALTRIALS: gov/study/NCT02811263.


Asunto(s)
Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Humanos , Recién Nacido , Frío , Discapacidades del Desarrollo/complicaciones , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/complicaciones , Temperatura
5.
J Pediatr ; : 114181, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38950817

RESUMEN

OBJECTIVE: To evaluate variations in management of therapeutic hypothermia (TH) for neonatal hypoxic-ischemic encephalopathy (HIE) among international clinical sites and to identify areas for harmonization. STUDY DESIGN: An electronic survey was sent to Children's Hospitals Neonatal Consortium site sponsors, Canadian Neonatal Network site investigators, members of the Newborn Brain Society, and American Academy of Pediatrics Neonatology chiefs. RESULTS: 105 sites responded, with most from high-income regions (n=95). Groupings were adapted from the United Nations regional groups: United States (US, n=52 sites); Canada (n=20); Western Europe and other states excluding Canada and US Group (WEOG, n=18); and non-WEOG (central and eastern Europe, Asia, Africa, Latin America, and Caribbean, n=15). Regional variations were seen in the eligibility criteria for TH, such as the minimum gestational age, grading of HIE severity, use of electroencephalography (EEG), and the frequency of providing TH for mild HIE. Active TH during transport varied among regions and was less likely in smaller volume sites. Amplitude-integrated (aEEG) and/or continuous EEG (cEEG) to determine eligibility for TH was used by most sites in WEOG and non-WEOG, but infrequently by the US and Canada Groups. For sedation during TH, morphine was most frequently used as first choice but there was relatively high (33%) use of dexmedetomidine in the US Group. Timing of brain MRI and neurodevelopmental follow-up (NDFU) were variable. NDFU occurred earlier and more frequently, although for a shorter duration, in the non-WEOG. CONCLUSIONS: We found significant variations in practices for TH for HIE across regions internationally. Future guidelines should incorporate resource availability in a global perspective.

6.
BMC Geriatr ; 24(1): 224, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438979

RESUMEN

This study aims to investigate the factors influencing the work status of retirees after retirement, especially focusing on self-employment and unpaid work. Data was taken and analyzed from the "Taiwan Health and Retirement Study," a nationally representative sample of retired personnel aged 50-74 in 2015-2016. Four types of work status were classified after retirement: Fully retired, Paid work, Self-employment, and Unpaid work. Multinomial regression analysis was used to explore the factors related to participation in paid, self-employed, and unpaid work. Results show that pre-retirement occupation was significantly associated with paid work after retirement. For example, retirees in Taiwan who were employed by private enterprises or self-employed before retirement were more likely to engage in paid work after retirement than civil servants before retirement. Two other factors, namely pre-retirement job stress and work flexibility, prolong the careers of retired workers, especially in self-employment and unpaid work after retirement. Gender also significantly affects the choice of work after retirement. These findings can be used as a reference for future policies on the aging labor force.


Asunto(s)
Envejecimiento , Jubilación , Humanos , Taiwán/epidemiología
7.
Nano Lett ; 23(23): 10765-10771, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37963268

RESUMEN

High-entropy alloy (HEA) nanoparticles (NPs) have been emerging with superior compositional tunability and multielemental synergy, presenting a unique platform for material discovery and performance optimization. Here we report a synthetic approach utilizing hollow-carbon confinement in the ordinary furnace annealing to achieve the nonequilibrium HEA-NPs such as Pt0.45Fe0.18Co0.12Ni0.15Mn0.10 with uniform size ∼5.9 nm. The facile temperature control allows us not only to reveal the detailed reaction pathway through ex situ characterization but also to tailor the HEA-NP structure from the crystalline solid solution to intermetallic. The preconfinement of metal precursors is the key to ensure the uniform distribution of metal nanoparticles with confined volume, which is essential to prevent the thermodynamically favored phase separation even during the ordinary furnace annealing. Besides, the synthesized HEA-NPs exhibit remarkable activity and stability in oxygen reduction catalysis. The demonstrated synthetic approach may significantly expand the scope of HEA-NPs with uncharted composition and performance.

8.
J Am Chem Soc ; 145(14): 7837-7844, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36995993

RESUMEN

As an important category of photochemical reactions, photocyclization is regarded as an ideal entry point for building intelligent photoresponsive materials. Herein, a series of aggregation-induced emission luminogens (AIEgens) with sensitive photoresponsive behavior are developed based on 2,3-diphenylbenzo[b]thiophene S,S-dioxide (DP-BTO), and the impacts of substituents with different electronic structures are investigated. The comprehensive experimental and computational characterizations reveal that their photoresponsive activity is resulted from triplet diradical-mediated intramolecular photocyclization, followed by dehydrogenation to yield stable polycyclic photoproducts. This photocyclization process is active in solution but suppressed in the solid state, and thus can act as a supplementary nonradiative decay channel for the excited state to contribute to AIE effect. Moreover, the generated triplet diradical intermediates upon light irradiation can effectively inhibit the growth of S. aureus, indicative of their promising application as antibacterial agents. This work provides an in-depth mechanistic description about the photocyclization of DP-BTO derivatives and furnishes a perspective on the correlation of photochemical decay and photophysical property.

9.
J Am Chem Soc ; 145(35): 19312-19320, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37611205

RESUMEN

The establishment of active sites as the frustrated Lewis pair (FLP) has recently attracted much attention ranging from homogeneous to heterogeneous systems in the field of catalysis. Their unquenched reactivity of Lewis acid and base pairs in close proximity that are unable to form stable adducts has been shown to activate small molecules such as dihydrogen heterolytically. Herein, we show that grafted Ru metal-organic framework-based catalysts prepared via N-containing linkers are rather catalytically inactive for H2 activation despite the application of elevated temperatures. However, upon light illumination, charge polarization of the anchored Ru bipyridine complex can form a transient Lewis acid-base pair, Ru+-N- via metal-to-ligand charge transfer, as confirmed by time-dependent density functional theory (TDDFT) calculations to carry out effective H2-D2 exchange. FTIR and 2-D NMR endorse the formation of such reactive intermediate(s) upon light irradiation.

10.
J Am Chem Soc ; 145(22): 11959-11968, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37216562

RESUMEN

In the pursuit of a highly reversible lithium-oxygen (Li-O2) battery, control of reaction sites to maintain stable conversion between O2 and Li2O2 at the cathode side is imperatively desirable. However, the mechanism involving the reaction site during charging remains elusive, which, in turn, imposes challenges in recognition of the origin of overpotential. Herein, via combined investigations by in situ atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS), we propose a universal morphology-dictated mechanism of efficient reaction sites for Li2O2 decomposition. It is found that Li2O2 deposits with different morphologies share similar localized conductivities, much higher than that reported for bulk Li2O2, enabling the reaction site not only at the electrode/Li2O2/electrolyte interface but also at the Li2O2/electrolyte interface. However, while the mass transport process is more enhanced at the former, the charge-transfer resistance at the latter is sensitively related to the surface structure and thus the reactivity of the Li2O2 deposit. Consequently, for compact disk-like deposits, the electrode/Li2O2/electrolyte interface serves as the dominant decomposition site, which causes premature departure of Li2O2 and loss of reversibility; on the contrary, for porous flower-like and film-like Li2O2 deposits bearing a larger surface area and richer surface-active structures, both the interfaces are efficient for decomposition without premature departure of the deposit so that the overpotential arises primarily from the sluggish oxidation kinetics and the decomposition is more reversible. The present work provides instructive insights into the understanding of the mechanism of reaction sites during the charge process, which offers guidance for the design of reversible Li-O2 batteries.

11.
J Am Chem Soc ; 145(26): 14548-14561, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37343126

RESUMEN

Catalytic NH3 synthesis and decomposition offer a new promising way to store and transport renewable energy in the form of NH3 from remote or offshore sites to industrial plants. To use NH3 as a hydrogen carrier, it is important to understand the catalytic functionality of NH3 decomposition reactions at an atomic level. Here, we report for the first time that Ru species confined in a 13X zeolite cavity display the highest specific catalytic activity of over 4000 h-1 for the NH3 decomposition with a lower activation barrier, compared to most reported catalytic materials in the literature. Mechanistic and modeling studies clearly indicate that the N-H bond of NH3 is ruptured heterolytically by the frustrated Lewis pair of Ruδ+-Oδ- in the zeolite identified by synchrotron X-rays and neutron powder diffraction with Rietveld refinement as well as other characterization techniques including solid-state nuclear magnetic resonance spectroscopy, in situ diffuse reflectance infrared transform spectroscopy, and temperature-programmed analysis. This contrasts with the homolytic cleavage of N-H displayed by metal nanoparticles. Our work reveals the unprecedented unique behavior of cooperative frustrated Lewis pairs created by the metal species on the internal zeolite surface, resulting in a dynamic hydrogen shuttling from NH3 to regenerate framework Brønsted acid sites that eventually are converted to molecular hydrogen.

12.
J Am Chem Soc ; 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37023113

RESUMEN

A cross-coupling reaction via the dehydrogenative route over heterogeneous solid atomic catalysts offers practical solutions toward an economical and sustainable elaboration of simple organic substrates. The current utilization of this technology is, however, hampered by limited molecular definition of many solid catalysts. Here, we report the development of Cu-M dual-atom catalysts (where M = Co, Ni, Cu, and Zn) supported on a hierarchical USY zeolite to mediate efficient dehydrogenative cross-coupling of unprotected phenols with amine partners. Over 80% isolated yields have been attained over Cu-Co-USY, which shows much superior reactivity when compared with our Cu1 and other Cu-M analogues. This amination reaction has hence involved simple and non-forceful reaction condition requirements. The superior reactivity can be attributed to (1) the specifically designed bimetallic Cu-Co active sites within the micropore for "co-adsorption-co-activation" of the reaction substrates and (2) the facile intracrystalline (meso/micropore) diffusion of the heterocyclic organic substrates. This study offers critical insights into the engineering of next-generation solid atomic catalysts with complex reaction steps.

13.
J Pediatr ; 261: 113560, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37321289

RESUMEN

OBJECTIVE: To determine cerebral glucose concentration and its relationship with glucose infusion rate (GIR) and blood glucose concentration in neonatal encephalopathy during therapeutic hypothermia (TH). METHODS: This was an observational study in which cerebral glucose during TH was quantified by magnetic resonance (MR) spectroscopy and compared with mean blood glucose at the time of scan. Clinical data (gestational age, birth weight, GIR, sedative use) that could affect glucose use were collected. The severity and pattern of brain injury on MR imaging were scored by a neuroradiologist. Student t test, Pearson correlation, repeated measures ANOVA, and multiple regression analysis were performed. RESULTS: Three-hundred-sixty blood glucose values and 402 MR spectra from 54 infants (30 female infants; mean gestational age 38.6 ± 1.9 weeks) were analyzed. In total, 41 infants had normal-mild and 13 had moderate-severe injury. Median GIR and blood glucose during TH were 6.0 mg/kg/min (IQR 5-7) and 90 mg/dL (IQR 80-102), respectively. GIR did not correlate with blood or cerebral glucose. Cerebral glucose was significantly greater during than after TH (65.9 ± 22.9 vs 60.0 ± 25.2 mg/dL, P < .01), and there was a significant correlation between blood glucose and cerebral glucose during TH (basal ganglia: r = 0.42, thalamus: r = 0.42, cortical gray matter: r = 0.39, white matter: r = 0.39, all P < .01). There was no significant difference in cerebral glucose concentration in relation to injury severity or pattern. CONCLUSIONS: During TH, cerebral glucose concentration is partly dependent on blood glucose concentration. Further studies to understand brain glucose use and optimal glucose concentrations during hypothermic neuroprotection are needed.


Asunto(s)
Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Recién Nacido , Lactante , Humanos , Femenino , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/patología , Glucemia , Hipotermia Inducida/efectos adversos , Hipotermia Inducida/métodos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética
14.
Mar Drugs ; 21(11)2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37999419

RESUMEN

A systematic investigation combined with a Global Natural Products Social (GNPS) molecular networking approach, was conducted on the metabolites of the deep-sea-derived fungus Samsoniella hepiali W7, leading to the isolation of three new fusaric acid derivatives, hepialiamides A-C (1-3) and one novel hybrid polyketide hepialide (4), together with 18 known miscellaneous compounds (5-22). The structures of the new compounds were elucidated through detailed spectroscopic analysis. as well as TD-DFT-based ECD calculation. All isolates were tested for anti-inflammatory activity in vitro. Under a concentration of 1 µM, compounds 8, 11, 13, 21, and 22 showed potent inhibitory activity against nitric oxide production in lipopolysaccharide (LPS)-activated BV-2 microglia cells, with inhibition rates of 34.2%, 30.7%, 32.9%, 38.6%, and 58.2%, respectively. Of particularly note is compound 22, which exhibited the most remarkable inhibitory activity, with an IC50 value of 426.2 nM.


Asunto(s)
Ácido Fusárico , Paecilomyces , Ácido Fusárico/farmacología , Macrófagos , Antiinflamatorios , Estructura Molecular
15.
Mar Drugs ; 21(10)2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37888439

RESUMEN

A systematic chemical investigation of the deep-sea-derived fungus Aspergillus versicolor 170217 resulted in the isolation of six new (1-6) and 45 known (7-51) compounds. The structures of the new compounds were established on the basis of exhaustive analysis of their spectroscopic data and theoretical-statistical approaches including GIAO-NMR, TDDFT-ECD/ORD calculations, DP4+ probability analysis, and biogenetic consideration. Citriquinolinones A (1) and B (2) feature a unique isoquinolinone-embedded citrinin scaffold, representing the first exemplars of a citrinin-isoquinolinone hybrid. Dicitrinones K-L (3-4) are two new dimeric citrinin analogues with a rare CH-CH3 bridge. Biologically, frangula-emodin (32) and diorcinol (17) displayed remarkable anti-food allergic activity with IC50 values of 7.9 ± 3.0 µM and 13.4 ± 1.2 µM, respectively, while diorcinol (17) and penicitrinol A (20) exhibited weak inhibitory activity against Vibrio parahemolyticus, with MIC values ranging from 128 to 256 µM.


Asunto(s)
Citrinina , Citrinina/química , Aspergillus/química , Hongos , Espectroscopía de Resonancia Magnética , Estructura Molecular
16.
Am J Orthod Dentofacial Orthop ; 164(1): 24-33, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36801092

RESUMEN

INTRODUCTION: This research project aimed to compare the number of maxillary incisors and canine movement between Invisalign and fixed orthodontic appliances using artificial intelligence and identify any limitations of Invisalign. METHODS: Sixty patients (Invisalign, n = 30; braces, n = 30) were randomly selected from the Ohio State University Graduate Orthodontic Clinic archive. Peer Assessment Rating (PAR) analysis was used to indicate the severity of the patients in both groups. To analyze the incisors and canine movement, specific landmarks were identified on incisors and canines using an artificial intelligence framework, two-stage mesh deep learning. Total average tooth movement in the maxilla and individual (incisors and canine) tooth movement in 6 directions (buccolingual, mesiodistal, vertical, tipping, torque, rotation) were then analyzed at a significance level of α = 0.05. RESULTS: Based on the posttreatment Peer Assessment Rating scores, the quality of finished patients in both groups was similar. In maxillary incisors and canines, there was a significant difference in movement between Invisalign and conventional appliances for all 6 movement directions (P <0.05). The greatest differences were with rotation and tipping of the maxillary canine, along with incisor and canine torque. The smallest statistical differences observed for incisors and canines were crown translational tooth movement in the mesiodistal and buccolingual directions. CONCLUSIONS: When comparing fixed orthodontic appliances to Invisalign, patients treated with fixed appliances were found to have significantly more maxillary tooth movement in all directions, especially with rotation and tipping of the maxillary canine.


Asunto(s)
Aparatos Ortodóncicos Removibles , Soportes Ortodóncicos , Maxilar , Inteligencia Artificial , Aparatos Ortodóncicos Fijos , Técnicas de Movimiento Dental
17.
Fetal Pediatr Pathol ; 42(4): 535-544, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36475417

RESUMEN

Background: Myelomeningocele (MMC) causes significant morbidity and mortality. Efforts have been directed to correct this defect in utero. The neuropathology literature on antenatally repaired MMC and associated complications in humans is limited. Case report: A 12-day-old female, who underwent prenatal MMC repair via a two-layer closure (dural replacement patch, primary skin closure), was born at 34 weeks' gestation. Her group B streptococcus positive mother received appropriate antepartum prophylactic antibiotics. She remained stable until day 11 of life when she underwent rapid clinical deterioration. Despite aggressive intervention, she expired on day 12. Review of placental pathology showed maternal and fetal inflammatory response. Autopsy revealed Gram-positive cocci and inflammation within the basilar leptomeninges and lumbosacral region. Neural and dermal elements were present within the MMC repair. Conclusion: This case documents integration of the dermal matrix patch to neural elements, adhering the spinal cord to scar tissue, the clinical implications of which remain unclear.


Asunto(s)
Meningomielocele , Humanos , Femenino , Embarazo , Meningomielocele/complicaciones , Placenta , Feto , Médula Espinal , Atención Prenatal
18.
Angew Chem Int Ed Engl ; 62(44): e202311082, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37698088

RESUMEN

We report an azide-functionalized cobaloxime proton-reduction catalyst covalently tethered into the Wurster-type covalent organic frameworks (COFs). The cobaloxime-modified COF photocatalysts exhibit enhanced photocatalytic activity for hydrogen evolution reaction (HER) in alcohol-containing solution with no presence of a typical sacrificial agent. The best performing cobaloxime-modified COF hybrid catalyzes hydrogen production with an average HER rate up to 38 µmol h-1 in ethanol/phosphate buffer solution under 4 h illumination. Ultrafast transient optical spectroscopy characterizations and charge carrier analysis reveal that the alcohol contents functioning as hole scavengers could be oxidized by the photogenerated holes of COFs to form aldehydes and protons. The consumption of the photogenerated holes thus suppresses exciton recombination of COFs and improves the ratio of free electrons that were effectively utilized to drive catalytic reaction for HER. This work demonstrates a great potential of COF-catalyzed HER using alcohol solvents as hole scavengers and provides an example toward realizing the accessibility to the scope of reaction conditions and a greener route for energy conversion.

19.
Angew Chem Int Ed Engl ; 62(31): e202305670, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37268600

RESUMEN

Lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) has been identified as the most used and effective p-dopant for hole transport layer (HTL) in perovskite solar cells (PSCs). However, the migration and agglomeration of Li-TFSI in HTL negatively impact PSCs performance and stability. Herein, we report an effective strategy for adding a liquid crystal organic small molecule (LQ) into Li-TFSI doped (2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'- spirobifluorene (Spiro-OMeTAD) HTL. It was found that the introduction of LQ into Spiro-OMeTAD HTL can efficiently enhance the charge carrier extraction and transportation in device, which can strongly retard the charge carrier recombination in device. Consequently, the PSCs efficiency is significantly enhanced to 24.42 % (Spiro-OMeTAD+LQ) from 21.03 % (Spiro-OMeTAD). The chemical coordination between LQ and Li-TFSI can strongly confine Li+ ions migration and agglomeration of Li-TFSI, thus, achieving the enhanced device stability. Only a 9 % efficiency degradation is observed for un-encapsulated device prepared with Spiro-OMeTAD and LQ after 1700 h under air environment, while the efficiency drops by 30 % for the reference device. This work provides an effective strategy for improving the efficiency and stability of PSCs, and gives some important insights for understanding intrinsic hot carriers dynamics for perovskite-based optoelectronic devices.

20.
BMC Plant Biol ; 22(1): 82, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35196981

RESUMEN

BACKGROUND: Golden 2-Like (G2-like) transcription factors play an important role in plant development. However, the roles of these G2-like regulatory genes in response to abiotic stresses in tomato are not well understood. RESULTS: In this study, we identified 66 putative G2-like genes in tomato (Solanum lycopersicum) and classified them into 5 groups (I to V) according to gene structure, motif composition and phylogenetic analysis. The G2-like genes were unevenly distributed across all 12 chromosomes. There were nine pairs of duplicated gene segments and four tandem duplicated SlGlk genes. Analysis of the cis-regulatory elements (CREs) showed that the promoter regions of SlGlks contain many kinds of stress- and hormone-related CREs. Based on RNA-seq, SlGlks were expressed in response to three abiotic stresses. Thirty-six differentially expressed SlGlks were identified; these genes have multiple functions according to Gene Ontology (GO) analysis and are enriched mainly in the zeatin biosynthesis pathway. Further studies exhibited that silencing SlGlk16 in tomato would reduce drought stress tolerance by earlier wilted, lower superoxide dismutase (SOD), peroxidase (POD) activities, less Pro contents and more MDA contents. CONCLUSIONS: Overall, the results of this study provide comprehensive information on G2-like transcription factors and G2-like genes that may be expressed in response to abiotic stresses.


Asunto(s)
Proteínas de Plantas/genética , Solanum lycopersicum/genética , Estrés Fisiológico/genética , Factores de Transcripción/genética , Mapeo Cromosómico , Sequías , Duplicación de Gen , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Estudio de Asociación del Genoma Completo , Solanum lycopersicum/efectos de los fármacos , Solanum lycopersicum/metabolismo , Malondialdehído/metabolismo , Filogenia , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Factores de Transcripción/química
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