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1.
BMC Pediatr ; 23(1): 392, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553623

RESUMO

BACKGROUND: As the survival rates of very low birth weight (VLBW) infants have increased, their neurodevelopmental outcomes are of concern. This study aims to determine the demographic and perinatal characteristics of premature infant according to head growth, identify clinical factors affecting growth catch-up, and explore differences in developmental outcomes according to catch-up states. METHODS: This nationwide prospective cohort study of Korean Neonatal Network data analyzed premature infants with very low birth weight (< 1,500 g) between 2014 and 2017. A total of 253 eligible infants who had completed the Bayley Scales of Infant and Toddler Development, Third Edition, were assigned into two groups: a catch-up (CU) group with a head circumference above the 10th percentile and a no catch-up (NCU) group with a head circumference below the 10th percentile at 18-24 months of corrected age (CA). RESULTS: Most (81.4%, 206/253) premature infants exhibited catch-up growth at 18-24 months of CA. Rates of microcephaly, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), sepsis, necrotizing enterocolitis (NEC), length of NICU stay, ventilation care, and parenteral nutrition were significantly greater in the NCU group (P < 0.05). On multiple linear regression analysis, BPD status was the most influential clinical factor affecting catch-up head growth after adjusting for gestational age, birth weight, and birth head circumference (adjusted OR 4.586, 95% CI 1.960-10.729). At 18-24 months of CA, the NCU group exhibited lower developmental indices and a higher rate of developmental delay than the CU group. Motor developmental delay was the most significant factor relevant to catch-up head growth, and the motor development difference between the two groups was only statistically significant after adjusting for four major neonatal morbidities: IVH, BPD, sepsis, and NEC status (adjusted OR 10.727, 95% CI 1.922-59.868). CONCLUSION: As association was observed between head growth catch-up status and developmental outcomes in VLBW infants at 18-24 months of CA. Key clinical factors associated with catch-up status included BPD and NEC status, length of parenteral nutrition, and ventilator care. Further study is needed to establish causality and explore additional factors that may influence developmental outcomes in this population.


Assuntos
Recém-Nascido de muito Baixo Peso , Sepse , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Estudos de Coortes , Estudos Prospectivos , Recém-Nascido Prematuro , Peso ao Nascer
2.
World J Surg ; 46(12): 2864-2871, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36207419

RESUMO

BACKGROUND: The purpose of our study was to assess the mid-term outcomes of the patients with grade III blunt thoracic aortic injury (BTAI) who were treated non-operatively and to determine the specific conditions for successful NOM. METHODS: We retrospectively reviewed patients with grade III BTAI at a single level 1 trauma center between January 2012 and March 2020, and compared the demographics and outcomes of NOM and thoracic endovascular aortic repair (TEVAR). We also examined the factors contributing to the selection of NOM by calculating the odds ratios for age, sex, initial systolic blood pressure, injury severity score, abbreviated injury scale score, pseudoaneurysm/neck (P/N) ratio, and comorbidity. RESULTS: In total, 46 adults were included. Thirty patients underwent NOM and 19 underwent TEVAR. The time from injury to computed tomography, hospital days, intensive care unit length of stay, and follow-up period showed no difference between the two groups. Aorta-related mortality was not observed in either group. Two patients (7.4%) in the NOM group experienced an increase in pseudoaneurysms: one of them underwent delayed surgical repair without complications, and the other maintained regular follow-up. The odds ratio for selecting NOM was significant when the P/N ratio was < 1.30 (OR = 4.687 [95% CI, 1.229-17.882], p = 0.024). CONCLUSIONS: We suggest that carefully selected patients with BTAI grade III could be observed nonoperatively or treated by delayed intervention on outpatient basis, and a P/N ratio < 1.30 can be used as a cutoff to decide treatment options for BTAI grade III.


Assuntos
Procedimentos Endovasculares , Traumatismos Torácicos , Lesões do Sistema Vascular , Ferimentos não Penetrantes , Adulto , Humanos , Estudos Retrospectivos , Lesões do Sistema Vascular/cirurgia , Resultado do Tratamento , Fatores de Tempo , Traumatismos Torácicos/cirurgia , Ferimentos não Penetrantes/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aorta Torácica/lesões , Aorta
3.
Angew Chem Int Ed Engl ; 61(42): e202210023, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36047567

RESUMO

The creation of self-healing polymers from commodity olefins is of great interest and importance but has remained a challenge to date. We report here for the first time the synthesis of self-healing polymers by catalyst-controlled polymerization of a simple commodity diene, isoprene. We found that polyisoprenes having an appropriate mixture (ca. 70/30) of 3,4- and cis-1,4-microstructures synthesized by using a half-sandwich scandium catalyst could act as excellent self-healing elastomers without any external intervention. The unprecedented self-healability could be ascribed to nanoscale heterogeneities formed by microphase separation of the relatively hard 3,4-segments from a flexible cis-1,4-segment matrix. The hydrogenated polyisoprenes (without C=C bonds) with the analogous microstructures also exhibited excellent mechanical and self-healing properties, further demonstrating that even simple polyolefins can be made self-healable if the microstructures are appropriately regulated.

4.
Angew Chem Int Ed Engl ; 61(2): e202110695, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34708895

RESUMO

Although covalent organic frameworks (COFs) with a graphene-like structure present unique chemical and physical properties, they are essentially insoluble and infusible crystalline powders with poor processability, hindering their further practical applications. How to improve the processability of COF materials is a major challenge in this field. In this contribution, we proposed a general side-chain engineering strategy to construct a gel-state COF with high processability. This method takes advantages of large and soft branched alkyl side chains as internal plasticizers to achieve the gelation of the COF. We systematically studied the influence of the length of the side chain on the COF gel formation. Benefitting from their machinability and flexibility, this novel COF gel can be easily processed into gel-type electrolytes with specific shape and thickness, which were further applied to assemble lithium-ion batteries that exhibited high cycling stability.

5.
Gut ; 70(4): 677-686, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33004550

RESUMO

OBJECTIVE: Thiopurines are widely used as maintenance therapy in inflammatory bowel disease (IBD) but the evidence base for their use is sparse and their role increasingly questioned. Using the largest series reported to date, we assessed the long-term effectiveness of thiopurines in ulcerative colitis (UC) and Crohn's disease (CD), including their impact on need for surgery. DESIGN: Outcomes were assessed in 11 928 patients (4968 UC, 6960 CD) in the UK IBD BioResource initiated on thiopurine monotherapy with the intention of maintaining medically induced remission. Effectiveness was assessed retrospectively using patient-level data and a definition that required avoidance of escalation to biological therapy or surgery while on thiopurines. Analyses included overall effectiveness, time-to-event analysis for treatment escalation and comparison of surgery rates in patients tolerant or intolerant of thiopurines. RESULTS: Using 68 132 patient-years of exposure, thiopurine monotherapy appeared effective for the duration of treatment in 2617/4968 (52.7%) patients with UC compared with 2378/6960 (34.2%) patients with CD (p<0.0001). This difference was corroborated in a multivariable analysis: after adjusting for variables including treatment era, thiopurine monotherapy was less effective in CD than UC (OR 0.47, 95% CI 0.43 to 0.51, p<0.0001). Thiopurine intolerance was associated with increased risk of surgery in UC (HR 2.44, p<0.0001); with a more modest impact on need for surgery in CD (HR=1.23, p=0.0015). CONCLUSION: Thiopurine monotherapy is an effective long-term treatment for UC but significantly less effective in CD.


Assuntos
Azatioprina/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Mercaptopurina/uso terapêutico , Adulto , Colite Ulcerativa/cirurgia , Doença de Crohn/cirurgia , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Reino Unido
6.
BMC Genomics ; 22(1): 142, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33639857

RESUMO

BACKGROUND: Tartary buckwheat (Fagopyrum tataricum), an important pseudocereal crop, has high economic value due to its nutritional and medicinal properties. However, dehulling of Tartary buckwheat is difficult owing to its thick and tough hull, which has greatly limited the development of the Tartary buckwheat processing industry. The construction of high-resolution genetic maps serves as a basis for identifying quantitative trait loci (QTLs) and qualitative trait genes for agronomic traits. In this study, a recombinant inbred lines (XJ-RILs) population derived from a cross between the easily dehulled Rice-Tartary type and Tartary buckwheat type was genotyped using restriction site-associated DNA (RAD) sequencing to construct a high-density SNP genetic map. Furthermore, QTLs for 1000-grain weight (TGW) and genes controlling hull type were mapped in multiple environments. RESULTS: In total, 4151 bin markers comprising 122,185 SNPs were used to construct the genetic linkage map. The map consisted of 8 linkage groups and covered 1444.15 cM, with an average distance of 0.35 cM between adjacent bin markers. Nine QTLs for TGW were detected and distributed on four loci on chromosome 1 and 4. A major locus detected in all three trials was mapped in 38.2-39.8 cM region on chromosome 1, with an LOD score of 18.1-37.0, and explained for 23.6-47.5% of the phenotypic variation. The genes controlling hull type were mapped to chromosome 1 between marker Block330 and Block331, which was closely followed by the major locus for TGW. The expression levels of the seven candidate genes controlling hull type present in the region between Block330 and Block336 was low during grain development, and no significant difference was observed between the parental lines. Six non-synonymous coding SNPs were found between the two parents in the region. CONCLUSIONS: We constructed a high-density SNP genetic map for the first time in Tartary buckwheat. The mapped major loci controlling TGW and hull type will be valuable for gene cloning and revealing the mechanism underlying grain development and easy dehulling, and marker-assisted selection in Tartary buckwheat.


Assuntos
Fagopyrum , Grão Comestível , Fagopyrum/genética , Ligação Genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
7.
J Am Chem Soc ; 143(40): 16750-16757, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34605645

RESUMO

The conversion of CO2 into functional materials under ambient conditions is a major challenge to realize a carbon-neutral society. Metal-organic frameworks (MOFs) have been extensively studied as designable porous materials. Despite the fact that CO2 is an attractive renewable resource, the synthesis of MOFs from CO2 remains unexplored. Chemical inertness of CO2 has hampered its conversion into typical MOF linkers such as carboxylates without high energy reactants and/or harsh conditions. Here, we present a one-pot conversion of CO2 into highly porous crystalline MOFs at ambient temperature and pressure. Cubic [Zn4O(piperazine dicarbamate)3] is synthesized via in situ formation of bridging dicarbamate linkers from piperazines and CO2 and shows high surface areas (∼2366 m2 g-1) and CO2 contents (>30 wt %). Whereas the dicarbamate linkers are thermodynamically unstable by themselves and readily release CO2, the formation of an extended coordination network in the MOF lattices stabilizes the linker enough to demonstrate stable permanent porosity.

8.
Scand J Psychol ; 62(4): 617-624, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34036581

RESUMO

Existing research has established that openness to experience can enhance dispositional awe. For the first time, the current study examines whether subjective socioeconomic status (SSES) moderates and a Zhong-Yong thinking style mediates this effect. A sample of 2,377 Chinese undergraduates (mean age 20.7, ranging from 18 to 26) was recruited. As shown in previous research, openness was found to be positively associated with dispositional awe. As predicted, the relationship was moderated by familial and school SSES. The positive correlation was significantly larger in cases of lower familial and school SSES. The mediating effect of Zhong-Yong thinking style was also supported in the relationship between openness and dispositional awe, as was the moderating effect of familial SSES; however, a suppressive effect was found for school SSES. The implications of this study are discussed herein.


Assuntos
Personalidade , Estudantes/psicologia , Adolescente , Adulto , China , Feminino , Humanos , Masculino , Classe Social , Estudantes/estatística & dados numéricos , Pensamento , Adulto Jovem
9.
J Am Chem Soc ; 142(33): 14357-14364, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32787252

RESUMO

The development of anhydrous proton-conducting materials is critical for the fabrication of high-temperature (>100 °C) polymer electrolyte membrane fuel cells (HT-PEMFCs) and remains a significant challenge. Covalent organic frameworks (COFs) are an emerging class of porous crystalline materials with tailor-made nanochannels and hold great potential for ion and molecule transport, but their poor chemical stability poses great challenges in this respect. In this contribution, we present a bottom-up self-assembly strategy to construct perfluoroalkyl-functionalized hydrazone-linked 2D COFs and systematically investigate the effect of different lengths of fluorine chains on their acid stability and proton conductivity. Compared with their nonfluorous parent COFs, fluorinated COFs possess structural ultrastability toward strong acids as a result of enhanced hydrophobicity (water contact angle of 144°). Furthermore, the superhydrophobic 1D nanochannels can serve as robust hosts to accommodate large amounts of phosphonic acid for fast and long-term proton conduction under anhydrous conditions and a wide temperature range. The anhydrous proton conductivity of fluorinated COFs is 4.2 × 10-2 S cm-1 at 140 °C after H3PO4 doping, which is 4 orders of magnitude higher than their nonfluorous counterparts and among the highest values of doped porous organic frameworks so far. Solid-state NMR studies revealed that H3PO4 forms hydrogen-boding networks with the frameworks and perfluoroalkyl chains of COFs, and most of the H3PO4 molecules are highly dynamic and mobile while the frameworks are rigid, which affords rapid proton transport. This work paves the way for the realization of the target properties of COFs through predesign and functionalization of the pore surface and highlights the great potential of COF nanochannels as a rigid platform for fast ion transportation.

10.
J Am Chem Soc ; 142(51): 21279-21284, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33295765

RESUMO

We propose a dynamic covalent chemistry (DCC)-induced linker exchange strategy for the structural transformation between covalent organic frameworks (COFs) and cages for the first time. Studies have shown that the COF-to-cage and cage-to-COF transformations were realized by using borate bonds and imine bonds, respectively, as linkages. Self-sorting experiments suggested that borate cages and imine COFs are thermodynamic minimum compounds. This research builds a bridge between discrete and polymeric organic scaffolds and broadens the knowledge of chemistry and materials for porous materials science.

11.
BMC Plant Biol ; 20(1): 505, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33148168

RESUMO

BACKGROUND: Tartary buckwheat has gained popularity in the food marketplace due to its abundant nutrients and high bioactive flavonoid content. However, its difficult dehulling process has severely restricted its food processing industry development. Rice-tartary buckwheat, a rare local variety, is very easily dehulled, but the cellular, physiological and molecular mechanisms responsible for this easy dehulling remains largely unclear. RESULTS: In this study, we integrated analyses of the comparative cellular, physiological, transcriptome, and gene coexpression network to insight into the reason that rice-tartary buckwheat is easy to dehull. Compared to normal tartary buckwheat, rice-tartary buckwheat has significantly brittler and thinner hull, and thinner cell wall in hull sclerenchyma cells. Furthermore, the cellulose, hemicellulose, and lignin contents of rice-tartary buckwheat hull were significantly lower than those in all or part of the tested normal tartary buckwheat cultivars, respectively, and the significant difference in cellulose and hemicellulose contents between rice-tartary buckwheat and normal tartary buckwheat began at 10 days after pollination (DAP). Comparative transcriptome analysis identified a total of 9250 differentially expressed genes (DEGs) between the rice- and normal-tartary buckwheat hulls at four different development stages. Weighted gene coexpression network analysis (WGCNA) of all DEGs identified a key module associated with the formation of the hull difference between rice- and normal-tartary buckwheat. In this specific module, many secondary cell wall (SCW) biosynthesis regulatory and structural genes, which involved in cellulose and hemicellulose biosynthesis, were identified as hub genes and displayed coexpression. These identified hub genes of SCW biosynthesis were significantly lower expression in rice-tartary buckwheat hull than in normal tartary buckwheat at the early hull development stages. Among them, the expression of 17 SCW biosynthesis relative-hub genes were further verified by quantitative real-time polymerase chain reaction (qRT-PCR). CONCLUSIONS: Our results showed that the lower expression of SCW biosynthesis regulatory and structural genes in rice-tartary buckwheat hull in the early development stages contributes to its easy dehulling by reducing the content of cell wall chemical components, which further effects the cell wall thickness of hull sclerenchyma cells, and hull thickness and mechanical strength.


Assuntos
Grão Comestível/metabolismo , Fagopyrum/metabolismo , Manipulação de Alimentos , Celulose/análise , Grão Comestível/química , Grão Comestível/citologia , Grão Comestível/fisiologia , Fagopyrum/citologia , Fagopyrum/genética , Fagopyrum/fisiologia , Perfilação da Expressão Gênica , Genes de Plantas , Polissacarídeos/análise , Transcriptoma
12.
Solid State Nucl Magn Reson ; 106: 101651, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058901

RESUMO

Atomic-level characterization of active pharmaceutical ingredients (API) is crucial in pharmaceutical industry because APIs play an important role in physicochemical properties of drug formulations. However, the analysis of targeted APIs in intact tablet formulations is less straightforward due to the coexistence of excipients as major components and different APIs at dilute concentrations (often below 10 â€‹wt% loading). Although solid-state (ss) NMR spectroscopy is widely used to investigate short-range order, polymorphism, and pseudo-polymorphism in neat pharmaceutical compounds, the analysis of complex drug formulations is often limited by overlapped signals that originate from structurally different APIs and excipients. In particular, such examples are frequently encountered in the analysis of 1H ssNMR spectra of pharmaceutical formulations. While the high-resolution in 1H ssNMR spectra can be attained by, for example, high magnetic fields accompanied by fast magic-angle spinning (MAS) approaches, the spectral complexity associated with the mixtures of compounds hinders the accurate determination of chemical shifts and through-space proximities. Here we propose a fast MAS (70 â€‹kHz) NMR experiment for the selective detection of 1H signals associated with an API from a severely overlapped NMR spectrum of a tablet formulation. Spectral simplification is achieved by combining (i) symmetry-based dipolar recoupling (SR412) rotational-echo saturation-pulse double-resonance (RESPDOR) with phase-modulate (PM) saturation pulses, (ii) radio frequency-driven recoupling (RFDR), and (iii) double-quantum excitation using Back-to-Back (BaBa) pulse sequence elements. First, 1H sites in close proximities to 14N nuclei of an API are excited using a PM-S-RESPDOR sequence, and simultaneously, the other unwanted 1H signals of excipients are suppressed. Then, 1H magnetization transfer to adjacent 1H sites in the API is achieved by spin diffusion process using a RFDR sequence, which polarizes to 1H sites within the crystalline API regions of the drug formulation. Next, a PM-S-RESPDOR-RFDR sequence is combined with a Back-to-Back (BaBa) sequence to elucidate local-structures and 1H-1H proximities of the API in a dosage form. The PM-S-RESPDOR-RFDR-BaBa experiment is employed in one- (1D) and two-dimensional (2D) versions to selectively detect the 1H ssNMR spectrum of l-cysteine (10.6 â€‹wt% or 0.11 â€‹mg) in a commercial formulation, and compared with the spectra of neat l-cysteine recorded using a standard BaBa experiment. The 2D 1H double-quantum-single-quantum (DQ-SQ) spectrum of the API (l-cysteine)-detected pharmaceutical tablet is in good agreement with the 2D 1H DQ-SQ spectrum obtained from the pure API molecule. Furthermore, the sensitivity and robustness of the experiment is examined by selectively detecting 1H{14N} signals in an amino acid salt, l-histidine.H2O.HCl.


Assuntos
Espectroscopia de Ressonância Magnética , Preparações Farmacêuticas/química , Composição de Medicamentos , Teoria Quântica , Comprimidos
13.
J Cell Biochem ; 120(4): 5085-5096, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30259568

RESUMO

20(S)-protopanaxadiol (PPD)-type ginsenosides are generally believed to be the most pharmacologically active components of Panax ginseng. These compounds induce apoptotic cell death in various cancer cells, which suggests that they have anti-cancer activity. Anti-angiogenesis is a promising therapeutic approach for controlling angiogenesis-related diseases such as malignant tumors, age-related macular degeneration, and atherosclerosis. Studies showed that 20(S)-PPD at low concentrations induces endothelial cell growth, but in our present study, we found 20(S)-PPD at high concentrations inhibited cell growth and mediated apoptosis in human umbilical vein endothelial cells (HUVECs). The mechanism by which high concentrations of 20(S)-PPD mediate endothelial cell apoptosis remains elusive. The present current study investigated how 20(S)-PPD induces apoptosis in HUVECs for the first time. We found that caspase-9 and its downstream caspase, caspase-3, were cleaved into their active forms after 20(S)-PPD treatment. Treatment with 20(S)-PPD decreased the level of Bcl-2 expression but did not change the level of Bax expression. 20(S)-PPD induced endoplasmic reticulum stress in HUVECs and stimulated UPR signaling, initiated by protein kinase R-like endoplasmic reticulum kinase (PERK) activation. Total protein expression and ATF4 nuclear import were increased, and CEBP-homologous protein (CHOP) expression increased after treatment with 20(S)-PPD. Furthermore, siRNA-mediated knockdown of PERK or ATF4 inhibited the induction of CHOP expression and 20(s)-PPD-induced apoptosis. Collectively, our findings show that 20(S)-PPD inhibits HUVEC growth by inducing apoptosis and that ATF4 expression activated by the PERK-eIF2α signaling pathway is essential for this process. These findings suggest that high concentrations of 20(S)-PPD could be used to treat angiogenesis-related diseases.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Apoptose/efeitos dos fármacos , Fator de Iniciação 2 em Eucariotos/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Sapogeninas/farmacologia , Transdução de Sinais , eIF-2 Quinase/metabolismo , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Modelos Biológicos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
J Am Chem Soc ; 141(3): 1227-1234, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30576136

RESUMO

Design of molecular structures showing fast ion conductive/transport pathways in the solid state has been a significant challenge. The amorphous or glassy phase in organic polymers works well for fast ion conductivity because of their dynamic and random structure. However, the main issue with these polymers has been the difficulty in elucidating the mechanisms of ion conduction and thus low designability. Furthermore, the amorphous or glassy state of ion conductive polymers often confronts the problems of structural/mechanical stabilities. Covalent organic frameworks (COFs) are an emerging class of crystalline organic polymers with periodic structure and tunable functionality, which exhibit potential as a unique ion conductor/transporter. Here, we describe the use of a COF as a medium for all-solid-state Li+ conductivity. A bottom-up self-assembly approach was applied to covalently reticulate the flexible, bulky, and glassy poly(ethylene oxide) (PEO) moieties that can solvate Li+ for fast transport by their segmental motion in the rigid two-dimensional COF architectures. Temperature-dependent powder X-ray diffraction and thermogravimetric analysis showed that the periodic structures are intact even above 300 °C, and differential scanning calorimetry and solid-state NMR revealed that the accumulated PEO chains are highly dynamic and exhibit a glassy state. Li+ conductivity was found to depend on the dynamics and length of PEO chains in the crystalline states, and solid-state Li+ conductivity of 1.33 × 10-3 S cm-1 was achieved at 200 °C after LiTFSI doping. The high conductivity at the specified temperature remains intact for extended periods of time as a result of the structure's robustness. Furthermore, we demonstrated the first application of a COF electrolyte in an all-solid-state Li battery at 100 °C.

15.
Chemistry ; 25(22): 5803-5808, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30801835

RESUMO

Charged or neutral adamantane guests can be encapsulated into the cavity of cationic metal-organic M6 L4 (bpy-cage, M=PdII (2,2'-bipyridine), L=2,4,6-tri(4-pyridyl)-1,3,5-triazine) cages through hydrophobic interaction. These encapsulations can provide an approach to control the net charge on the resulting cage-guest complexes and regulate their charge-dominated assembly into hollow spherical blackberry-type assemblies in dilute solutions: encapsulation of neutral guests will hardly influence their self-assembly process, including the blackberry structure size, which is directly related to the intercage distance in the assembly; whereas encapsulating negatively (positively) charged guests resulted in a shorter (longer) intercage distance with larger (smaller) assemblies formed. Therefore, the host-guest chemistry approach can be used to tune the intercage distance accurately.

16.
Molecules ; 24(21)2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31652756

RESUMO

Phthalates are widely used plasticizers that can cause endocrine disruption, mutagenicity, and carcinogenic effects and can contaminate food through various pathways. Investigations are scanty on phthalate pollution of livestock and poultry meat and their dietary exposure to humans. The present study assessed residual levels of phthalates in unpackaged pork (30 samples) and unpackaged chicken (30 samples) and their relevance to meat consumption and health risks in the Taiwanese population. Phthalate quantity was assessed by liquid chromatography-tandem mass spectrometry; the materials included diisononyl phthalate, diisodecyl phthalate, benzyl butyl phthalate, di-2-ethylhexyl phthalate (DEHP), and di-n-butyl phthalate. The Taiwan Food and Drug Administration (TFDA) has established values of tolerable daily intake (TDI) for the five phthalates. The major compound detected was DEHP, which ranged from 0.62 to 0.80 mg/kg in two pork samples, and 0.42-0.45 mg/kg in three chicken samples. Collectively, 8.33% of the phthalate-residue-containing samples tested positive for DEHP. The concentrations of DEHP were lower than the screening value of 1.0 mg/kg, as defined by the TFDA. Health risk was calculated as the estimated daily intake (DI) for any likely adverse effects; the DI of DEHP residues was <1% of the TDI value. The estimated risk was insignificant and considered to be safe, indicating that there is no risk to the health of Taiwanese population due to meat consumption. However, it is suggested that a phthalate monitoring program in meat should be instituted for any possible effects in future on human health.


Assuntos
Poluentes Ambientais/análise , Análise de Alimentos , Ácidos Ftálicos/análise , Carne de Porco/análise , Aves Domésticas , Animais , Cromatografia Líquida , Humanos , Taiwan , Espectrometria de Massas em Tandem
17.
Turk J Med Sci ; 49(5): 1308-1316, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31648436

RESUMO

Background/aim: Acute aortic dissection (AAD) is a rare but fatal disease if left untreated. Symptoms are often similar to common conditions; therefore, the diagnostic strategy is important. We aimed to identify the atypical symptoms in a timely manner without putting patients at greater risk for undetected AAD. Materials and methods: We conducted a retrospective observational study of 59 AAD patients with both atypical and typical symptoms from January 2012 to December 2016. Patients with atypical symptoms continuing more than 30 min underwent a D-dimer test and computed tomography (CT) or computed tomographic angiography (CTA). Results: Of the 59 AAD patients, 22 were atypical. In the atypical group, the median delay time in our hospital was 3.1 h; average delay time after July 2015 was shorter than average delay time before June 2015 (16.59 ± 24.70 vs. 1.90 ± 0.57 h, P = 0.076). Conclusions: For patients in the emergency department who are suspected of having AAD, incorporating atypical symptoms with high levels of D-dimer into a triage strategy could improve the efficiency of clinical decision making. Furthermore, essential education directed towards the recognition of the atypical symptoms of AAD for front-line physicians may aid in a timely diagnosis, as compared with the usual assessments in the emergency department.


Assuntos
Dissecção Aórtica/diagnóstico , Doença Aguda , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/patologia , Angiografia por Tomografia Computadorizada , Creatina Quinase/sangue , Serviço Hospitalar de Emergência , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , L-Lactato Desidrogenase/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de Tempo , Tomografia Computadorizada por Raios X
18.
Chemphyschem ; 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29737041

RESUMO

The beta (ß)-sheet structures of oligopeptides and polypeptides can be formed in anti-parallel (AP) and parallel (P) forms, which is an important feature to understand such structures. In principle, P- and AP-ß-sheet structures can be identified by the presence (AP) or absence (P) of inter-strand 1 HNH /1 HNH correlations on a diagonal in the corresponding 2D 1 H double quantum (DQ)/1 H single quantum (SQ) spectrum due to the different inter-strand 1 HNH /1 HNH distances between the two arrangements. However, the 1 HNH /1 HNH peaks overlap with the 1 HNH3+ /1 HNH3+ peaks, which always give cross-peaks regardless of the ß-sheet arrangement. The 1 HNH3+ /1 HNH3+ peaks disturb the observation of the presence/absence of 1 HNH /1 HNH correlations and the assignment of 1 HNH and 1 HNH3+ is not always available. Here, 3D 14 N/1 H DQ/1 H SQ correlation solid-state NMR experiments at fast magic angle spinning (70 kHz) are introduced to distinguish AP- and P-ß-sheet structures. The 14 N dimension allows the distinction of 1 HNH /1 HNH peaks from 1 HNH3+ /1 HNH3+ peaks with clear assignments of 1 HNH and 1 HNH3+ . In addition, the high natural abundance of 1 H and 14 N enables 3D 14 N/1 H DQ/1 H SQ experiments of oligo-alanines (Ala3-6 ) in four hours without isotope labelling.

20.
Angew Chem Int Ed Engl ; 57(24): 7034-7039, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29696757

RESUMO

Precise control of the molecular arrangements at the interface between the electron donor and acceptor in mixed bulk heterojunctions (BHJs) remains challenging, despite the correlation between structural characteristics and efficiency in organic photovoltaics (OPVs). This study reveals that the substitution patterns of linear and branched alkyl side chains on electron-donating/-accepting alternating copolymers can control the positions of an acceptor molecule (C60 ) around the π-conjugated main chains in mixed BHJs. Two-dimensional solid-state NMR demonstrates a marked difference in the location of C60 in the blend films. A copolymer with an electron-accepting unit positioned in close proximity to C60 demonstrated higher OPV performance in combination with various fullerene derivatives. This molecular design offers precise control over the interfacial molecular structure, thereby paving the way for overcoming the current limitations of OPVs comprising mixed BHJs.

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