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1.
Chem Commun (Camb) ; 60(34): 4597-4600, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38586897

RESUMEN

We have found an efficient adsorption feature provided by an NaCaA-85 zeolite for N2O even at 298 K and at lower pressures: N2O adsorption capacities of 1.33 mmol g-1 and 4.69 mmol g-1 under respective pressures of 0.3 and at 100 Torr, respectively, indicating the best performance among adsorbent materials so far reported. These adsorption peculiarities will pave a new way for developing excellent materials working for adsorption/separation processes of N2O.

2.
Hosp Pediatr ; 14(2): e123-e131, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38273770

RESUMEN

CONTEXT: Nonpharmacologic distraction (NPD) during medical procedures in children is known to be beneficial to patients; however, no reviews have assessed their benefits to medical providers. OBJECTIVES: We aimed to assess the benefits of NPD to medical providers. DATA SOURCES: We searched 5 databases for relevant articles. STUDY SELECTION: Peer-reviewed published randomized controlled trials comparing NPD with standard care that included children who had undergone medical procedures were included. DATA EXTRACTION: Primary outcomes were procedure time, number of medical staff involved, and initial success rate of venipuncture. Two reviewers assessed the risk of bias by using the Cochrane Collaboration (Oxford, United Kingdom)'s Randomized Controlled Trials Risk of Bias Tool, and we performed a meta-analysis to assess efficacy. RESULTS: We included 22 trials with 1968 participants. The main NPD was audiovisual distraction, such as tablets. No significant difference was found in venipuncture procedure time (mean difference: -9.79; 95% confidence interval: -22.38 to 2.81; low certainty). We found no studies on the number of medical staff. CONCLUSIONS: Our review did not find any clear NPD-associated benefit for the medical provider. The review included a small amount of literature, analyzed a small number of cases, and had a low certainty of evidence regarding procedure duration; therefore, further studies are needed to conclude the benefits to clinicians of NPD.


Asunto(s)
Flebotomía , Niño , Humanos , Reino Unido , Flebotomía/psicología , Atención
3.
Acad Emerg Med ; 31(1): 61-70, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37688572

RESUMEN

OBJECTIVE: Pain in pediatric musculoskeletal (MSK) injuries can lead to increased anxiety, fear, and avoidance of medical care, making analgesic management critical. Therefore, we evaluated analgesic efficacy and adverse effects to select the optimal analgesic agent in pediatric patients with MSK injuries. METHODS: Four databases were searched from inception to March 2023 for peer-reviewed, open randomized controlled trials (RCTs). Inclusion criteria were: (1) trials with RCT design, (2) children aged 1 month-18 years with MSK injury, (3) outpatient setting, (4) interventions and control, (5) primary outcome of pain score at 60 and 120 min and secondary outcome of adverse effects, and (6) full-text and peer-reviewed articles. Two reviewers screened, extracted data, and assessed the risk of bias. A frequentist random-effects network meta-analysis (NMA) was performed. Certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation working group approach. RESULTS: We included eight trials comprising 1645 children. Ibuprofen was significantly associated with pain reduction at 120 min, compared with acetaminophen (SMD 0.31 [95% CI 0.11-0.51]; moderate certainty) and opioids (SMD 0.34 [95% CI 0.20-0.48]; moderate certainty). Compared with opioids alone, ibuprofen-opioid combination was significantly associated with pain reduction at 120 min (SMD 0.19 [95% CI 0.03-0.35]). No significant differences were found in pain interventions at 60 min. Ibuprofen had statistically fewer adverse events than opioids (RR, 0.54 [95% CI 0.33-0.90]; moderate certainty) and ibuprofen with opioids (RR 0.47 [95% CI 0.25-0.89]; moderate certainty). In terms of limitations, the eight RCTs included had relatively small sample sizes; only two were high-quality RCTs. CONCLUSIONS: Our NMA found ibuprofen to be the most effective and least adverse analgesic in pediatric patients with MSK injuries.


Asunto(s)
Analgésicos , Sistema Musculoesquelético , Dolor , Niño , Humanos , Acetaminofén/uso terapéutico , Analgésicos/efectos adversos , Analgésicos Opioides/uso terapéutico , Ibuprofeno/efectos adversos , Sistema Musculoesquelético/lesiones , Sistema Musculoesquelético/patología , Metaanálisis en Red , Dolor/tratamiento farmacológico
4.
Am J Emerg Med ; 68: 161-169, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37027937

RESUMEN

OBJECTIVES: Although airway management is important in pediatric resuscitation, the effectiveness of bag-mask ventilation (BMV) and advanced airway management (AAM), such as endotracheal intubation (ETI) and supraglottic airway (SGA) devices, for prehospital resuscitation of pediatric out-of-hospital cardiac arrest (OHCA) remains unclear. We aimed to determine the efficacy of AAM during prehospital resuscitation of pediatric OHCA cases. METHODS: We searched four databases from their inception to November 2022 and included randomized controlled trials and observational studies with appropriate adjustments for confounders that evaluated prehospital AAM for OHCA in children aged <18 years in quantitative synthesis. We compared three interventions (BMV, ETI, and SGA) via network meta-analysis using the GRADE Working Group approach. The outcome measures were survival and favorable neurological outcomes at hospital discharge or 1 month after cardiac arrest. RESULTS: Five studies (including one clinical trial and four cohort studies with rigorous confounding adjustment) involving 4852 patients were analyzed in our quantitative synthesis. Compared with ETI, BMV was associated with survival (relative risk [RR] 0.44 [95% confidence intervals (CI) 0.25-0.77]) (very low certainty). There were no significant association with survival in the other comparisons (SGA vs. BMV: RR 0.62 [95% CI 0.33-1.15] [low certainty], ETI vs. SGA: RR 0.71 [95% CI 0.39-1.32] [very low certainty]). There was no significant association with favorable neurological outcomes in any comparison (ETI vs. BMV: RR 0.33 [95% CI 0.11-1.02]; SGA vs. BMV: RR 0.50 [95% CI 0.14-1.80]; ETI vs. SGA: RR 0.66 [95% CI 0.18-2.46]) (all very low certainty). In the ranking analysis, the hierarches for efficacy for survival and favorable neurological outcome were BMV > SGA > ETI. CONCLUSION: Although the available evidence is from observational studies and its certainty is low to very low, prehospital AAM for pediatric OHCA did not improve outcomes.


Asunto(s)
Reanimación Cardiopulmonar , Servicios Médicos de Urgencia , Paro Cardíaco Extrahospitalario , Humanos , Niño , Metaanálisis en Red , Manejo de la Vía Aérea , Intubación Intratraqueal
5.
ACS Omega ; 8(4): 4285-4293, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36743070

RESUMEN

The quantitative evaluation of the drug mixing condition was conducted for application in the forensic discrimination of drug powders using micro Fourier transform infrared (FT-IR) spectroscopy. Bromhexine hydrochloride (BHCl) and p-hydroxybenzoic acid (PHBA) were used as the simulated drug and additive, respectively. Equal masses of two chemicals were (1) simply mixed, (2) homogenized using agate mortar, or (3) dissolved in methanol and dried, and then (4) homogenized using agate mortar. The mixed powders dispersed on BaF2 plates were subjected to mapping analysis of micro FT-IR spectroscopy using synchrotron radiation (SR) or globar light in transmission mode with aperture sizes of 2.5 x 2.5 and 10 x 10µm2, and x-y scanning steps of 2.5 and 10 µm, respectively. The areas of the vibration bands specific to BHCl (C-N bending) and PHBA (C=O stretching) were converted to the molar contents (CBHCl, CPHBA), and the relative content ratio (RCR: CPHBA/[CBHCl + CPHBA]) was used as one mixing parameter. The resulting two-dimensional distribution map provided the relative spatial localizations of the two species, and frequency histograms with a horizontal axis of RCR were plotted to evaluate the RCR distribution. The percentage frequency of the extreme value in which RCR was 0 or 1 (%EV) was used as one mixing index. After excluding the extreme values, the coefficient of variation (CV) of the RCR distribution was used as another mixing index. The differentiation among four mixing modes could be evaluated from the standpoint of %EV and CV, and the discrimination capacity by SR instrument was superior to that by globe light instrument.

6.
J Phys Chem B ; 126(22): 4143-4151, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35639685

RESUMEN

Elucidating the state of interfacial water, especially the hydrogen-bond configurations, is considered to be key for a better understanding of the functions of polymers that are exhibited in the presence of water. Here, an analysis in this direction is conducted for two water-insoluble biocompatible polymers, poly(2-methoxyethyl acrylate) and cyclic(poly(2-methoxyethyl acrylate)), and a non-biocompatible polymer, poly(n-butyl acrylate), by measuring their IR spectra under humidified conditions and by carrying out theoretical calculations on model complex systems. It is found that the OH stretching bands of water are decomposed into four components, and while the higher-frequency components (with peaks at ∼3610 and ∼3540 cm-1) behave in parallel with the C═O and C-O-C stretching and CH deformation bands of the polymers, the lower-frequency components (with peaks at ∼3430 and ∼3260 cm-1) become pronounced to a greater extent with increasing humidity. From the theoretical calculations, it is shown that the OH stretching frequency that is distributed from ∼3650 to ∼3200 cm-1 is correlated to the hydrogen-bond configurations and is mainly controlled by the electric field that is sensed by the vibrating H atom. By combining these observed and calculated results, the configurations of water at the interface of the polymers are discussed.


Asunto(s)
Polímeros , Agua , Hidrógeno , Enlace de Hidrógeno , Polímeros/química , Espectrofotometría Infrarroja/métodos , Agua/química
8.
Food Sci Nutr ; 9(9): 4916-4926, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34532003

RESUMEN

We analyzed edible potato starch and observed the interaction between its granular structure and water molecules. We studied the changes caused by gelatinization during heating and stirring using microscopy, micro-FT-IR spectroscopy, and X-ray scattering techniques. A wide range of spatial scales was revealed using these various techniques. The rate of gelatinization varied significantly and was dependent on the starch concentration. The process of adsorption of water on starch molecules was studied using the humidity-controlled FT-IR spectroscopy technique. Furthermore, by comparing the X-ray scattering profiles of dry and wet granules, the 9-nm repeat "cluster" structure was studied. A gradual collapse of the granules occurred during the processes of heating and stirring. A clustered smectic structure and a smectic-like structure were observed in the opaque gel after gelatinization. Upon further heating, a transparent gel was obtained after the melting of the cluster.

9.
Sci Rep ; 10(1): 19423, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33173082

RESUMEN

Lewy bodies (LBs) and glial cytoplasmic inclusions (GCIs) are specific aggregates found in Parkinson's disease (PD) and multiple system atrophy (MSA), respectively. These aggregates mainly consist of α-synuclein (α-syn) and have been reported to propagate in the brain. In animal experiments, the fibrils of α-syn propagate similarly to prions but there is still insufficient evidence to establish this finding in humans. Here, we analysed the protein structure of these aggregates in the autopsy brains of patients by synchrotron Fourier-transform infrared micro-spectroscopy (FTIRM) analysis without extracting or artificially amplifying the aggregates. As a result, we found that the content of the ß-sheet structure in LBs in patients with PD was significantly higher than that in GCIs in patients with MSA (52.6 ± 1.9% in PD vs. 38.1 ± 0.9% in MSA, P < 0.001). These structural differences may provide clues to the differences in phenotypes of PD and MSA.


Asunto(s)
Citoplasma/metabolismo , Cuerpos de Inclusión/química , Cuerpos de Lewy/química , Neuroglía/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Anciano , Anciano de 80 o más Años , Autopsia , Encéfalo/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atrofia de Múltiples Sistemas/metabolismo , Enfermedad de Parkinson/metabolismo
10.
J Oleo Sci ; 69(10): 1307-1315, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32908096

RESUMEN

Ceramide, an intercellular lipid of the stratum corneum, plays an essential role in making the skin barrier. One problem with the use of medical adhesive tape or sheets for skin is that their repeated attachment and detachment may cause some damage to the skin. An attempt has been made to eliminate this problem by mixing ceramide into the adhesive of sheets, and has delivered excellent clinical results. This study aimed to investigate whether ceramide is transferred from the adhesive with added ceramide to the skin. An adhesive sheet was prepared by adding synthetic ceramide (CER) to UV-curable acrylic adhesive gel. After affixing the adhesive sheet to human skin for a certain period, it was peeled off and cut perpendicular to the adhesive surface. Synchrotron micro-infrared spectroscopy of the sectioned samples showed that the ceramide concentration in the gel sheet decreases as the application time to human skin increases. This is thought to be due to the release of CER from the gel sheet.


Asunto(s)
Adhesivos , Ceramidas/administración & dosificación , Ceramidas/metabolismo , Liberación de Fármacos , Absorción Cutánea , Piel/metabolismo , Cinta Quirúrgica , Ceramidas/análisis , Geles , Humanos , Espectrofotometría Infrarroja
11.
Nat Commun ; 10(1): 3711, 2019 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-31420538

RESUMEN

Molecular crystals are not known to be as stiff as metals, composites and ceramics. Here we report an exceptional mechanical stiffness and high hardness in a known elastically bendable organic cocrystal [caffeine (CAF), 4-chloro-3-nitrobenzoic acid (CNB) and methanol (1:1:1)] which is comparable to certain low-density metals. Spatially resolved atomic level studies reveal that the mechanically interlocked weak hydrogen bond networks which are separated by dispersive interactions give rise to these mechanical properties. Upon bending, the crystals significantly conserve the overall energy by efficient redistribution of stress while perturbations in hydrogen bonds are compensated by strengthened π-stacking. Furthermore we report a remarkable stiffening and hardening in the elastically bent crystal. Hence, mechanically interlocked architectures provide an unexplored route to reach new mechanical limits and adaptability in organic crystals. This proof of concept inspires the design of light-weight, stiff crystalline organics with potential to rival certain inorganics, which currently seem inconceivable.

12.
Nat Commun ; 10(1): 997, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30824701

RESUMEN

Chemiluminescence, a process of transduction of energy stored within chemical bonds of ground-state reactants into light via high-energy excited intermediates, is known in solution, but has remained undetected in macroscopic crystalline solids. By detecting thermally induced chemiluminescence from centimeter-size crystals of an organic peroxide here we demonstrate direct transduction of heat into light by thermochemiluminescence of bulk crystals. Heating of crystals of lophine hydroperoxide to ~115 °C results in detectable emission of blue-green light with maximum at 530 nm with low chemiluminescent quantum yield [(2.1 ± 0.1) × 10‒7 E mol‒1]. Spectral comparison of the thermochemiluminescence in the solid state and in solution revealed that the solid-state thermochemiluminescence of lophine peroxide is due to emission from deprotonated lophine. With selected 1,2-dioxetane, endoperoxide and aroyl peroxide we also establish that the thermochemiluminescence is common for crystalline peroxides, with the color of the emitted light varying from blue to green to red.

13.
J Oleo Sci ; 68(3): 273-280, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30760666

RESUMEN

A recent study has shown that the addition of ceramide to adhesive materials of medical sheets or tapes improves or maintains skin barrier functions despite the irritation and damage caused by the repeated removal of the sheet or tape. This fact may imply that ceramide molecules are released from the adhesive material and penetrate the skin. In this study, we investigated whether ceramide molecules are released from a UV-curable acrylic adhesive resin (acResin®) sheet containing ceramide molecules attached to a cultured skin sample by estimating the local ceramide concentration from the data obtained by synchrotron Fourier transform infrared micro-spectroscopy analysis. Since section samples of uniform thickness could not be prepared, the intensity data of the amide I peak originating from ceramide were normalized by using the intensity data of the ester peak originating from the resin matrix. This analysis enabled the quantification of the change in local ceramide concentrations in the sheet samples. This result indicates that ceramide molecules were released from the acResin® sheet attached to the cultured skin sheet.


Asunto(s)
Resinas Acrílicas/química , Adhesivos/química , Ceramidas/análisis , Liberación de Fármacos , Resinas Acrílicas/efectos de la radiación , Adhesivos/efectos de la radiación , Ceramidas/química , Humanos , Piel/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Rayos Ultravioleta
14.
Hum Genome Var ; 6: 56, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31934343

RESUMEN

Autosomal recessive primary microcephaly 5 (MCPH5) is caused by pathogenic variants in ASPM. Using whole-exome sequencing, we diagnosed two siblings with MCPH5. A known pathogenic variant (NM_018136.4: c.9697C > T, p.(Arg3233*)) and a novel pathogenic variant (c.1402_1406del, p.(Asn468Serfs*2)) of ASPM were identified in affected siblings with normal intelligence. Their pathogenic variants were not located in the critical regions of ASPM, but the relationship between the genotypes and their normal intelligence was unclear.

15.
Sci Rep ; 7(1): 12930, 2017 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-29018228

RESUMEN

Spin liquid (SL) systems have been the subject of much attention recently, as they have been theoretically predicted to not freeze, even at 0 K. Despite extensive searches being made for such a system, only a few candidates have been found. All of these candidates share geometrical frustrations that are based on triangular lattices. We applied vibrational spectroscopy to one of the candidates of a molecule-based SL system, and we compared its results against three antiferromagnetic compounds and four charge-ordered compounds. All of their structural motifs belong to triangular lattices. The C=C stretching modes in the SL state indicated that there were charge and lattice fluctuations. These fluctuations were suppressed but non-negligible in the AF compounds. This finding is potentially significant, as it indicates that a hidden lattice and charge fluctuation are the driving force of a geometrical frustration, which eventually leads to a SL state.

16.
Langmuir ; 33(34): 8404-8412, 2017 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-28737401

RESUMEN

Effect of alkyl chain spacer length between the charged groups (CSL) in zwitterionic poly(sulfobetaine) (PSB) brushes on the hydration state was investigated. PSB brushes with ethyl (PMAES), propyl (PMAPS), or butyl (PMABS) CSL were prepared by surface-initiated atom transfer radical polymerization on silicon wafers. Hydration states of the PSB brushes in aqueous solutions and/or humid vapor were investigated by contact angle measurement, infrared spectroscopy, AFM observation, and neutron reflectivity. The PSB brushes are swollen in humid air and deionized water due to the hydration of the charged groups leading to the reduction of hydrated PSB brushes/water interfacial free energy. The hydrated PSB brushes exhibit clear interface with low interfacial roughness due to networking of the PSB brush chains through association of the SBs. The hydrated PSB brushes produce diffusive swollen layer in the presence of NaCl because of the charge screening followed by SB dissociation by the bound ions. The ionic strength sensitivity in the hydration got more significant with increasing the CSL in SBs because of the augmentation in partial charge by charged group separation.

17.
J Phys Condens Matter ; 29(23): 235802, 2017 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-28497775

RESUMEN

We have measured the infrared reflectivity of single-crystalline samples of LaCo1-x Rh x O3 (x = 0, 0.05 and 0.10) from 10 to 300 K from 0.05 to 0.15 eV. We find that the optical phonons of the Co-O stretching mode depend on temperature and the Rh content. Analysis with three Lorentz oscillators reveals that the spin state of Co3+ in LaCo1-x Rh x O3 can be understood in terms of a solid solution of low-spin- and high-spin-state Co3+ ions, and the substituted Rh ion retains some fraction of the high-spin Co3+ ions down to low temperature.

18.
J Am Chem Soc ; 139(6): 2318-2328, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28075578

RESUMEN

The range of unit cell orientations generated at the kink of a bent single crystal poses unsurmountable challenges with diffraction analysis and limits the insight into the molecular-scale mechanism of bending. On a plastically bent crystal of hexachlorobenzene, it is demonstrated here that spatially resolved microfocus infrared spectroscopy using synchrotron radiation can be applied in conjunction with periodic density functional theory calculations to predict spectral changes or to extract information on structural changes that occur as a consequence of bending. The approach reproduces well the observed trends, such as the wall effects, and provides estimations of the vibrational shifts, unit cell deformations, and intramolecular parameters. Generally, expansion of the lattice induces red-shift while compression induces larger blue-shift of the characteristic ν(C-C) and ν(C-Cl) modes. Uniform or non-uniform expansion or contraction of the unit cell of 0.1 Å results in shifts of several cm-1, whereas deformation of the cell of 0.5° at the unique angle causes shifts of <0.5 cm-1. Since this approach does not include parameters related to the actual stimulus by which the deformation has been induced, it can be generalized and applied to other mechanically, photochemically, or thermally bent crystals.

19.
Sci Rep ; 5: 17625, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26621077

RESUMEN

Lewy bodies (LBs), which mainly consist of α-synuclein (α-syn), are neuropathological hallmarks of patients with Parkinson's disease (PD). The fine structure of LBs is unknown, and LBs cannot be made artificially. Nevertheless, many studies have described fibrillisation using recombinant α-syn purified from E. coli. An extremely fundamental problem is whether the structure of LBs is the same as that of recombinant amyloid fibrils. Thus, we used synchrotron Fourier transform infrared micro-spectroscopy (FTIRM) to analyse the fine structure of LBs in the brain of PD patients. Our results showed a shift in the infrared spectrum that indicates abundance of a ß-sheet-rich structure in LBs. Also, 2D infrared mapping of LBs revealed that the content of the ß-sheet structure is higher in the halo than in the core, and the core contains a large amount of proteins and lipids.


Asunto(s)
Cuerpos de Lewy/metabolismo , Cuerpos de Lewy/patología , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Sincrotrones , alfa-Sinucleína/metabolismo , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Espectroscopía Infrarroja por Transformada de Fourier
20.
Nat Chem ; 7(1): 65-72, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25515892

RESUMEN

The exceptional mechanical flexibility observed with certain organic crystals defies the common perception of single crystals as brittle objects. Here, we describe the morphostructural consequences of plastic deformation in crystals of hexachlorobenzene that can be bent mechanically at multiple locations to 360° with retention of macroscopic integrity. This extraordinary plasticity proceeds by segregation of the bent section into flexible layers that slide on top of each other, thereby generating domains with slightly different lattice orientations. Microscopic, spectroscopic and diffraction analyses of the bent crystal showed that the preservation of crystal integrity when stress is applied on the (001) face requires sliding of layers by breaking and re-formation of halogen-halogen interactions. Application of stress on the (100) face, in the direction where π···π interactions dominate the packing, leads to immediate crystal disintegration. Within a broader perspective, this study highlights the yet unrecognized extraordinary malleability of molecular crystals with strongly anisotropic supramolecular interactions.

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