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1.
J Environ Manage ; 365: 121536, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38909577

RESUMO

In this study, a series of BiTeX (X = Cl, Br, I) photocatalysts were successfully synthesized via a simple hydrothermal method. The synthesis process involved dissolving BiX3 and Te powder in toluene to identify the most efficient material for photocatalytic activity. The main objective of this approach is to facilitate the conversion of carbon dioxide into sustainable solar fuels, such as alcohols and hydrocarbons, offering an appealing solution to address environmental concerns and energy crises. The BiTeX photocatalysts demonstrated significant proficiency in converting CO2 into CH4, particularly BiTeCl exhibited a notable photocatalytic conversion rate of up to 0.51 µmolg-1h-1. The optimized BiTeX photocatalysts displayed a gradual and selective transition from CO2 to CH4, ultimately producing valuable hydrocarbons (C2+). Furthermore, owing to their ability to reduce CO2, these photocatalysts show promise as materials for mitigating environmental pollution.


Assuntos
Dióxido de Carbono , Luz , Dióxido de Carbono/química , Catálise
2.
J Phys Chem Lett ; 15(4): 912-918, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241171

RESUMO

Triplet transitions of light-emitting materials, including rose bengal, tris(2-phenylpyridine)iridium(III) [Ir(ppy)3], tris(1-phenylisoquinoline)iridium(III) [Ir(piq)3], and bis[2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium(III) (FIrpic), were studied using step-scan time-resolved Fourier-transform near-infrared spectroscopy. The samples were excited to their singlet excited states by a 355 nm laser and then underwent efficient conversions/crossings to their triplet manifolds. For rose bengal, a transient absorption band appeared at 9400 cm-1, attributed to the T3 ← T1 transition based on the corresponding time evolution and the theoretical calculations. For Ir(ppy)3, Ir(piq)3, and FIrpic, the most intense bands were observed at 7700, 7500, and 7500 cm-1 and assigned to T7 ← T1, T6 ← T1, and T6 ← T1 transitions, respectively. For Ir(ppy)3, the most intense band involved transitions between different triplet metal-to-ligand charge transfer (3MLCT) states, while for Ir(piq)3 and FIrpic, they involved a metal center to 3MLCT transition. These T1 states were assigned to 3MLCT.

3.
Small ; 19(44): e2303491, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37381620

RESUMO

Semiconductor crystals have generally shown facet-dependent electrical, photocatalytic, and optical properties. These phenomena have been proposed to result from the presence of a surface layer with bond-level deviations. To provide experimental evidence of this structural feature, synchrotron X-ray sources are used to obtain X-ray diffraction (XRD) patterns of polyhedral cuprous oxide crystals. Cu2 O rhombic dodecahedra display two distinct cell constants from peak splitting. Peak disappearance during slow Cu2 O reduction to Cu with ammonia borane differentiates bulk and surface layer lattices. Cubes and octahedra also show two peak components, while diffraction peaks of cuboctahedra are comprised of three components. Temperature-varying lattice changes in the bulk and surface regions also show shape dependence. From transmission electron microscopy (TEM) images, slight plane spacing deviations in surface and inner crystal regions are measured. Image processing provides visualization of the surface layer with depths of about 1.5-4 nm giving dashed lattice points instead of dots from atomic position deviations. Close TEM examination reveals considerable variation in lattice spot size and shape for different particle morphologies, explaining why facet-dependent properties are emerged. Raman spectrum reflects the large bulk and surface lattice difference in rhombic dodecahedra. Surface lattice difference can change the particle bandgap.

4.
Phys Chem Chem Phys ; 25(17): 12165-12173, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37070738

RESUMO

Nitrite (NO2-) is one of the common salts in aqueous aerosols, and its photolytic products, nitric oxide (NO) and hydroxyl radical (OH), have potential for use in the oxidation of organic matter, such as dissolved formaldehyde, methanediol (CH2(OH)2), which is regarded as the precursor of atmospheric formic acid. In this work, the simulation of UVA irradiation in an aqueous mixture of NaNO2/CH2(OH)2 was carried out via continuous exposure with a 365 nm LED lamp, and the reaction evolutions were probed by in situ and real-time infrared and Raman spectroscopy, which provided multiplexity in the identification of the relevant species and the corresponding reaction evolution. Although performing infrared absorption measurements in aqueous solution seemed impracticable due to the strong interference of water, the multiplexity of the vibrational bands of parents and products in the non-interfered infrared regimes and the conjunction with Raman spectroscopy still make it possible to perform in situ and real-time characterization of the photolytic reaction in the aqueous phase, supplementary to chromatographic approaches. During the 365 nm irradiation, NO2- and CH2(OH)2 gradually decreased, concomitant with the formation of nitrous oxide (N2O) and formate (HCOO-) in the early period and carbonate (CO32-) in the late period, as revealed by the vibrational spectra. The losses or the gains of the aforementioned species increased with increases in the concentration of CH2(OH)2 and the irradiation flux of the 365 nm UV light. The ionic product HCOO- was also confirmed by ion chromatography, but oxalate (C2O42-) was absent in the vibrational spectra and ion chromatogram. The reaction mechanism is reasonably proposed on the basis of the evolutions of the aforementioned species and the predicted thermodynamic favorableness.

5.
ACS Omega ; 5(25): 15620-15630, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32637838

RESUMO

The electronic and vibrational structures of trinickel metal string complexes [Ni3(dpa)4X2]1-,0,1+ (X = Cl, NCS) were investigated using both theoretical calculations and spectroscopic methods. We used the density functional theory (DFT) method B3LYP*-D3, including less exact exchange energy and the van der Waals interaction of metal ions, to obtain the geometries and vibrational structures, which were found to be in excellent agreement with the experimental data. The ground state of Ni3(dpa)4X2 is an antiferromagnetic (AF) singlet state, and the next state is a quintet state, which was detected using temperature-dependent Raman spectroscopy under a magnetic field. The vibrational structure of the quintet state is nearly identical to that of the AF state, according to the measured Raman spectra, except that the stretching of Ni-Cl is blue-shifted from 282.5 cm-1 in the AF state to 283.8 cm-1 in the quintet state. Two oxidized Ni3 complexes were found to have [Ni3]7+ cores, the doublet [Ni3(dpa)4]3+ without axial ligands and the quartet [Ni3(dpa)4X2]+. Complex [Ni3(dpa)4X2]-, which was produced from a reduction reaction by gold nanoparticles at room temperature, consists of a quartet state as the ground state and a doublet state lying nearby.

6.
J Dent Sci ; 15(2): 193-199, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32595901

RESUMO

BACKGROUND/PURPOSE: Pediatric obstructive sleep apnea (OSA) might be a serious cause of neurocognitive deficits, behavioral changes, and craniofacial disharmony in children at very young age with mild type of OSA. This study aims to examine the effect of mild OSA on craniofacial morphology as well as dental arch morphology and characteristics in preschool children. MATERIALS AND METHODS: The test group comprised 16 preschool children (11 boys, 5 girls; mean age: 5.14 years old; mean AHI: 2.02) with confirmed polysomnographic diagnosis of mild OSA. Ten control subjects also underwent polysomnography (5 boys, 5 girls; mean age: 5.18 years old; median AHI: 0.43). Lateral cephalometric radiographs and dental arch impressions were obtained and measured. A survey on characteristics and quality of life (OSA-18) was filled out by study participants' caregivers. RESULTS: For craniofacial morphology, a significant increase in ANB angle, a decrease in SNB angle, and larger overjet size were seen in the group with mild OSA, compared with the control group. More frequent sleep disturbances and mood swing were also found in children with mild OSA, based on the OSA-18 assessment. CONCLUSION: Preschool children with mild OSA present the following: skeletal Class II pattern with a more retrognathic mandible, increased overjet size, and more pronounced symptoms in the domains of sleep and emotion. Dental arch constriction is not a typical feature in our sample of Asian preschool children with mild OSA.

7.
Chem Commun (Camb) ; 56(34): 4660-4663, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32211656

RESUMO

A method for the catalytic α-arylation of indolin-3-ones was developed. The catalytic system comprising Pd(dba)2 and PAd3 was found to be optimal for the transformation. The protocol features broad functional group compatibility in that a range of arylated indoxyl derivatives bearing a fully substituted carbon center was synthesized with high efficiency. A preliminary bioassay study revealed that the selected indole-substituted indolin-3-ones exhibit favorable cytotoxic activities against HCT-116 cancer cell line.

8.
RSC Adv ; 10(57): 34493-34500, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-35514408

RESUMO

Using low-wavenumber Raman spectroscopy in combination with theoretical calculations via solid-state density functional theory (DFT)-D3, we studied the vibrational structures and interaction with solvent of poly-l-proline and the oligoproline P12 series. The P12 series includes P12, the positively charged amino acid residue (arginine and lysine) N-terminus proline oligomers RP11 and KP11, and the C-terminus P11R and P11K. We assigned the spring-type phonon mode to 74-76 cm-1 bands for the PPI and PPII conformers and the carbonyl group ring-opening mode 122 cm-1 in the PPI conformer of poly-l-proline. Amide I and II were assigned based on the results of mode analysis for O, N, and C atom displacements. The broad band feature of the H-bond transverse mode in the Raman spectra indicates that the positively charged proline oligomers PPII form H-bonds with water in the solid phase, whereas P12 is relatively more hydrophobic. In propanol, the PPI conformer of the P12 series forms less H-bond network with the solvent. The PPII conformer exhibits a distinct Raman band at 310 cm-1, whereas the PPI has bands at 365, 660, and 960 cm-1 with reasonable intensity that can be used to quantitatively determine these two conformational forms. The 365 cm-1 mode comprising the motion of a C[double bond, length as m-dash]O group turning to the helix axis was used to monitor the isomerization reaction PPI ↔ PPII. In pure propanol, RP11 and KP11 were found to have mostly PPI present, but P11R and P11K preferred PPII. After adding 20% water, the PPI in P11R and P11K was completely converted to PPII, whereas a small fraction of PPI remained in RP11 and KP11. The substituted positively charged amino acid affected the balance of the PPI/PPII population ratio.

9.
J Phys Chem B ; 123(43): 9123-9133, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31584816

RESUMO

Covalently circularized nanodiscs using circular membrane scaffold protein (MSP) serve as a suitable membrane mimetic for transmembrane proteins by providing stability and tunability in lipid compositions, providing controllable biological environments for targeted proteins. In this work, monomeric bacteriorhodopsin (mbR) was embedded in lipid nanodiscs of different lipid compositions using negatively charged lipid dioleoyl phosphatidylglycerol (DOPG) and the zwitterion lipid dioleoyl phosphatidylcholine (DOPC), and the events associated with the retinal Schiff base, including the thermal isomerization during the dark adaptation, photoisomerization, and deprotonation, were investigated. The retinal thermal isomerization from all-trans, 15-anti to the 13-cis, 15-syn configuration during the dark adaptation was accelerated in the DOPG bilayer, whereas the processes in the DOPC bilayer and in Triton X-100 micelles were similar. This observation indicated that the negatively charged lipid reduced the barrier for retinal thermal isomerization at C13═C14-C15═N in the ground electronic state. Furthermore, the broader absorption contour of mbR in the DOPC nanodisc probably indicated various retinal isomers in the light-adapted state, consistent with the observed nontwo-state dark adaptation kinetics. Moreover, the kinetics of the photoisomerization of the retinal was slightly decelerated upon increasing the content of DOPC. However, the cascading deprotonation of the protonated Schiff base is not dependent on the types of the surrounding lipids in the nanodiscs. In summary, our research deepens the understanding of the coupling between lipid membrane and the photochemistry of bR retinal Schiff base. Combined with the results of our previous works (Lee, T.-Y.; Yeh, V.; Chuang, J.; Chan, J. C. C.; Chu, L.-K.; Yu, T.-Y. Biophys. J. 2015, 109, 1899-1906; Kao, Y.-M.; Cheng, C.-H.; Syue, M.-L.; Huang, H.-Y.; Chen, I-C.; Yu, T.-Y.; Chu, L.-K. J. Phys. Chem. B 2019, 123, 2032-2039), these outcomes extend our understanding of the control of photochemistry and biophysical events for other photosynthetic proteins via altering the lipid environments.


Assuntos
Bacteriorodopsinas/química , Nanoestruturas/química , Fosfatidilcolinas/química , Fosfatidilgliceróis/química , Fotoquímica , Retinaldeído/química , Bases de Schiff/química , Prótons , Estereoisomerismo
10.
ACS Omega ; 4(3): 5327-5334, 2019 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459703

RESUMO

The facet-dependent redox reactions of diruthenium metal-string complexes by gold nanoparticles (AuNPs) are explored by using the surface-enhanced Raman scattering (SERS) technique. Gold nano-rhombic dodecahedrons (AuRDs), gold nanocubes (AuNCs), and gold octahedrons (AuOhs) with exclusive facets {110}, {100}, and {111}, respectively, were synthesized. These AuNPs linked face-to-face by metal-string complexes Ru2M(dpa)4Cl2 (dpa = dipyridyl amino, M = Ni, Cu) with chloride axial ligands serve as both SERS substrates and reducing agents in the reactions. We employ the diruthenium core in these complexes with multiple redox states to study the reduction ability of varied AuNP facets upon plasmonic excitation. In Ru2Ni(dpa)4Cl2, the Ru-Ru stretching mode νRu-Ru str. lies at 327 cm-1 on the SERS substrate AuOh, but this band shifts to 313 cm-1 on the AuRD and AuNC. The diruthenium moiety was reduced to [Ru2]4+ by the AuRD facet {110} and the AuNC {100}. The gold nanorods in the solution prepared with metal-string complexes bridging head-to-head on {111} facets were used for the SERS substrate. The SERS curves of the complexes in these self-assembled head-to-head rods display νRu-Ru str. at 327 cm-1, which is assigned to having an [Ru2]5+ core. Hence, facets {110} and {100} have a reduction reactivity greater than that of {111}. In Ru2Cu(dpa)4Cl2, the νRu-Ru str. is observed to lie at 312 cm-1 on AuRD, but shifts to 320 cm-1 on the AuNC and AuOh. In the latter cases, the diruthenium moiety was reduced to having a charge of 4+ with electronic configuration π*2δ*2, whereas the former case band at 312 cm-1 with a weaker Ru-Ru bonding is also attributed to [Ru2]4+ but with electron configuration π*4. π*4 lies at an energy greater than π*2δ*2. The electrochemical SERS spectra of diruthenium complexes were recorded to verify their oxidation states. Conclusively, these results yield the reduction reactivity of the following facet: {110} > {100} > {111}. According to the results of the redox reactions, the valence states of the diruthenium metal-string complexes are verified. In the [Ru2] n+ core, n = 4 π*4, 4 π*2δ*2, 5 π*2δ*, and 6 π*δ*, and the νRu-Ru str. is 312, 320, 327, and 337 cm-1, respectively.

11.
Biosci. j. (Online) ; 35(4): 1276-1289, july/aug. 2019. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1048933

RESUMO

In this study, leftover roots of Sansing green onions grown without toxic chemicals in Sansing Township, Ilan County, Taiwan were used as a raw material of skincare products. The raw material was extracted from the green onion roots by ultrasound in a low-temperature, safe and pollution-free environment. We hope to develop cleansers and other facial care products made of this natural, environmentally friendly, safe and affordable raw material so that people with sensitive skin can also use these products. We also hope that this study can contribute to circular economy and achieve the goal of green innovation by recycling the leftover roots. In terms of anti-oxidation, the DPPH free radical scavenging ability of 2.5 mg/mL green onion root extract was equivalent to 98% of that of 1 mg/mL BHT; the Fe2+ chelating ability was equivalent to 87.0% of that of 0.02 mg/mL EDTA; the superoxide anions scavenging ability of 2.5 mg/mL green onion root extract was equivalent to 84.2% of that of 1 mg/mL BHT and 80.4% of that of 0.05 mg/mL vitamin C. With respect to melanin synthesis inhibition, the green onion root extract's ability to inhibit dopachrome, the intermediate product of melanin, was positively correlated to its concentration, i.e., the higher the concentration of the green onion root extract, the better the inhibition ability. The IC50 of green onion root extract was 1.83 mg/mL, while, for comparison, the IC50 of vitamin C was 0.62 mg/mL. Furthermore, according to the cell survival assay, no obvious cytotoxic effect was found with the increase in the concentration of the green onion root extract. The whitening effect improved after 30 days of test. The improvement rate was 5.6% for 2.5 mg/mL green onion root extract, 3.1% for 1.25 mg/mL extract, and 1.7% for 0.625 mg/mL extract. The moisture retention also improved after 30 days of test. The moisture retention improvement rate was 22.7% for 2.5 mg/mL green onion root extract, 21.6% for 1.25 mg/mL extract, and 15.4% for 0.625 mg/mL extract. Based on the experiments, the green onion root extract obtained from ultrasound not only did not cause skin allergy and irritation but also showed anti-aging, melanin synthesis inhibition, whitening and moisture retention effects. The results showed that the green onion root extract can improve the moisture retention and whitening effect of the mask.


Neste estudo, restos de raízes de cebolinhas Sansing, cultivadas sem produtos químicos tóxicos no município de Sansing, Condado de Ilan, Taiwan, foram utilizadas como matéria-prima de produtos para a pele. A matéria-prima foi extraída das raízes de cebolinha por ultrassom em um ambiente de baixa temperatura, seguro e livre de poluição. Esperamos desenvolver produtos de limpeza e outros produtos para cuidados faciais produzidos com essa matéria-prima natural, ecologicamente correta, segura e acessível, para Improvement rate (%) Moisture retention Whitening effect 7.65 1.29 que pessoas com pele sensível também possam usar esses produtos. Também esperamos que este estudo possa contribuir para a economia circular e alcançar o objetivo da inovação ecológica, reciclando restos das raízes. Em termos de anti-oxidação, a capacidade de sequestro do radical livre DPPH de 2,5 mg/mL de extrato de raiz de cebolinha foi equivalente a 98% de 1 mg/mL de BHT; a capacidade quelante do Fe2+ foi equivalente a87,0% de 0,02 mg/mL de EDTA; a capacidade de sequestro de ânions superóxidos de 2,5 mg/mL de extrato de raiz de cebolinha foi equivalente a 84,2% de 1 mg/mL BHT e 80,4% de 0,05 mg/mL de vitamina C. No que diz respeito à inibição da síntese de melanina, a capacidade do extrato de raiz de cebolinha de inibir o dopacrômio, o metabolito intermediário de melanina, foi positivamente correlacionada com a sua concentração, ou seja, quanto maior a concentração do extrato de raiz de cebolinha, maior a capacidade de inibição. O IC50 de extrato de raiz de cebolinha foi de 1,83 mg/mL, enquanto que, por comparação, o IC50 de vitamina C foi de 0,62mg/mL. Além disso, de acordo com o ensaio de sobrevivência celular, nenhum efeito citotóxico foi observado com o aumento da concentração do extrato de raiz de cebolinha. O efeito de branqueamento melhora após 30 dias de ensaio. A melhoria foi de 5,6% para 2,5 mg/mL de extrato de raiz de cebolinha, 3,1% para 1,25 mg/mL de extrato e 1,7% para 0,625 mg/mL de extrato. A retenção de umidade também melhorou depois de 30 dias de teste. A taxa de melhoria de retenção de umidade foi de 22,7% para 2,5 mg/mL de extrato de raiz de cebolinha, 21,6% para 1,25 mg/mL de extrato, e 15,4% para 0,625 mg/mL de extrato.Com base nas experiências efetuadas, o extrato de raiz de cebolinha obtida por ultrassom não só não causa alergia nem irritação da pele, mas também demonstrou atividade anti-envelhecimento, inibição da síntese de melanina, capacidade de branqueamento e retenção de umidade. Os resultados mostraram que o extrato de raiz de cebolinha pode melhorar a retenção de umidade e efeito de branqueamento da máscara.


Assuntos
Raízes de Plantas , Cebolas , Cosméticos , Antioxidantes
12.
Clin Neuropharmacol ; 42(4): 133-135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31135390

RESUMO

OBJECTIVES: Neurosyphilis, an infectious neuroinflammatory disorder, could cause diverse neuropsychiatric symptoms mimicking disorders of schizophrenia and dementia; hence, it is known as the "chameleon of psychiatry." Here, we present a subject with neurosyphilis with schizophrenic features and share the treatment outcome. METHODS: A 42-year-old single man had schizophrenic-like features and cognitive dysfunction for 1 year. Neurosyphilis was confirmed by a cerebral spinal fluid study. The brain image revealed multiple punctuated white matter gliosis in the bilateral frontal lobes and old lacunar infarctions in the bilateral basal hippocampus. The neuropsychiatric functions were declined until adjunctive memantine therapy. RESULTS: With the add-on therapy of memantine 10 mg daily, the psychotic and dementic symptoms markedly improved, and the patient recovered to the premorbid state in the 2-year follow-up course. CONCLUSIONS: Memantine has an adjunctive effect on neurosyphilis-related neuropsychiatric disorder via modulation of the glutamatergic neurotransmission and microglia-induced neuroinflammation.


Assuntos
Disfunção Cognitiva/etiologia , Memantina/uso terapêutico , Neurossífilis/complicações , Esquizofrenia/etiologia , Adulto , Humanos , Masculino
13.
J Phys Chem B ; 123(9): 2032-2039, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30742764

RESUMO

Preparing transmembrane protein in controllable lipid bilayers is essential for unravelling the coupling of the environments and its dynamic functions. Monomerized bacteriorhodopsin (mbR) embedded in covalently circularized nanodiscs was prepared with dimyristoylphosphatidylglycerol (DMPG) lipid and circular membrane scaffold proteins of two different sizes, cE3D1 and cΔ H5, respectively. The retinal photoisomerization kinetics and thermodynamic photocycle were examined by femtosecond and nanosecond transient absorption, respectively, covering the time scale from femtoseconds to hundreds of milliseconds. The kinetics of the retinal isomerization and proton migration from the protonated Schiff base to Asp-85 were not significantly different for monomeric bR solubilized in Triton X-100 or embedded in circularized nanodiscs. This can be ascribed to the local tertiary structures at the retinal pocket vicinity being similar among monomeric bR in various membrane mimicking environments. However, the aforementioned processes are intrinsically different for trimeric bR in purple membrane (PM) and delipidated PM. The reprotonation of the deprotonated Schiff base from Asp-96 in association with the decay of intermediate M, which involved wide-ranged structural alteration, manifested a difference in terms of the oligomeric statuses, as well as a slight dependence on the size of the nanodisc. In summary, bR oligomeric statuses, rather than the environmental factors, such as membrane mimicking systems and nanodisc size, play a significant role in bR photocycle associated with short-range processes, such as the retinal isomerization and deprotonation of protonated Schiff base at the retinal pocket. On the other hand, the environmental factors, such as the types of membrane mimicking systems and the size of nanodiscs, affect those dynamic processes involving wider structural alterations during the photocycle.


Assuntos
Bacteriorodopsinas/química , Retinaldeído/química , Bacteriorodopsinas/efeitos da radiação , Halobacterium salinarum/química , Isomerismo , Cinética , Luz , Bicamadas Lipídicas/química , Nanoestruturas/química , Fosfatidilgliceróis/química , Fotoquímica , Estrutura Quaternária de Proteína , Retinaldeído/efeitos da radiação , Espectrofotometria , Termodinâmica
14.
Sleep Med ; 60: 20-25, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30466820

RESUMO

INTRODUCTION: Sleep problems, neuro-developmental development, and sleep-disordered-breathing (SDB), are reported as more prevalent in premature infants than in full-term infants. We investigated the relationship between neuro-development, and SDB in preterm infants at 24 months corrected age (CA) with a narrow palatal presentation over time. METHODS: We enrolled infants 40 weeks or younger at birth collecting obstetric and birth data. Participants were followed up at 6, 12, 18, and 24 months CA. We evaluated craniofacial development by inspecting and photo documenting hard palate; sleep using sleep diary, actigraphy and night-time polysomnography-PSG-; and development using Bayley- Scales-of-Infant-Development and Denver-Developmental-Screening-Test (DDST) at each visit and comparing results at six months and two years. RESULTS: 244 premature infants [139 (57.0%) boys, [at birth: mean gestational age-GA- 31.5 ± 3.2 weeks, 1691.9 ± 593.9 g, 40.2 ± 5.2 cm], and 30 full term infants (50% boys), [mean GA 39.3 ± 1.0 weeks, 3131.0 ± 390.0 g, and 49.38 ± 2.0 cm] were enrolled in the study. At 6 and 24 months, 65.2% premature infants had a narrow hard palate (NHP). At 24 months, 79% had an apnea-hypopnea- index (AHI) > 1 events/hour at PSG, with a mean AHI of 3.00 ± 2.95. Only 10% of full term infants had NHP at birth and the mean AHI was 0.5 ± 0.2 event/hour at 24 months. CONCLUSION: Preterm infants have a higher occurrence of NHP at birth. At two years of age they have more sleep problems, most commonly associated with obstructive-SDB, and a higher rate of development delays. Frequency of NHP is still abnormally high, suggesting not only abnormal orofacial growth over-time, but also impact of this abnormal growth in the genesis of the obstructive-SDB.


Assuntos
Anormalidades Craniofaciais , Recém-Nascido Prematuro , Palato Duro/anormalidades , Síndromes da Apneia do Sono , Actigrafia , Desenvolvimento Infantil , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Polissonografia
15.
J Org Chem ; 83(23): 14688-14697, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30277073

RESUMO

Making use of temperature-controlled thiation as a key operation, a simple route to 2-aminothiophenes or thieno[2,3- c]isothiazoles has been newly developed wherein the 2-aminothiophene nucleus was formed through an initial formation of thioamide followed by a 5-exo-dig addition to the tethered alkyne; however, under harsher thermal conditions, excess sulfur-transferring reagents enabled further oxidative thiation to generate the corresponding thieno[2,3- c]isothiazoles.

16.
Biosci. j. (Online) ; 34(4): 1102-1113, july/aug. 2018.
Artigo em Inglês | LILACS | ID: biblio-967291

RESUMO

This study aims to develop rice bran-based skin care products with moisturizing, whitening and anti-wrinkle effects similar to Pitera (a natural by-product of sake lees fermentation) but without alcohol irritation for sensitive skin. To achieve this objective, bran from organic indica rice was fermented by lactic acid bacteria in a safe and pollution-free environment. In terms of anti-oxidation, the DPPH .free radical scavenging ability of 100.0 mg/mL bran fermentation solution was 71.4% of that of vitamin C of the same concentration; and its Fe2+ chelating ability was 79.0% of that of EDTA of the same concentration. Moreover, the superoxide anion scavenging ability of 10.0 mg/mL bran fermentation solution was equivalent to 42.9% of that of BHT of similar concentration. With respect to inhibition of melanin synthesis, the bran fermentation solution's ability to inhibit the synthesis of dopachrome, the intermediate of melanin, was positively correlated to its concentration, i.e., the higher the concentration of the bran fermentation solution was, the better the inhibition ability was. The IC50 of bran fermentation solution was 9.23 mg/mL while, for comparison, that of arbutin was 0.52 mg/mL. Furthermore, according to the cell survival assay, no obvious cytotoxic effect was found with the increase of the concentration of the bran fermentation solution. As for whitening evaluation, the whitening improvement rate was 9.29% in 20% dilution, 5.36% in 15% dilution, 3.69% in 10% dilution, 2.43% in 5% dilution, 0.35% in 1% dilution in a 30-day test. In the moisturizing evaluation, the moisturizing improvement rate was 44.31% in 20% dilution, 20.48% in 15% dilution, 7.68% in 10% dilution, 6.02% in 5% dilution and 2.02% in 1% dilution. Based on the experimental results, the alcohol-free rice bran fermentation solution not only did not cause irritation but also had antiaging, melanin synthesis inhibition, whitening and moisturizing effects. Therefore, it is advisable to add rice bran fermentation solution to cleaning mousse, shower gel, serum and essence to turn bran from compost of agricultural waste (cradle to grave) into a natural raw material (cradle to cradle) of the cosmetic industry, creating new value of rice bran.


Este estudo tem como objetivo desenvolver produtos de cuidados com a pele baseados em farelo de arroz com hidratação, branqueamento e efeitos antiarrugas semelhantes à Pitera (um subproduto natural da fermentação de sauces), mas sem irritação com álcool para a pele sensível. Para alcançar esse objetivo, o farelo do arroz indica orgânico foi fermentado por bactérias do ácido lático em um ambiente seguro e livre de poluição. Em termos de antioxidação, a capacidade de eliminação radical de DPPH.free de 100,0 mg / mL de solução de fermentação de farelo foi de 71,4% da vitamina C da mesma concentração; E sua capacidade de quelação Fe2 + foi de 79,0% da EDTA da mesma concentração. Além disso, a capacidade de eliminação de aniões superóxido de 10,0 mg / mL de solução de fermentação de farelo era equivalente a 42,9% da BHT de concentração similar. Com relação à inibição da síntese de melanina, a capacidade da solução de fermentação do farelo de inibir a síntese do dopachrome, o intermediário da melanina, correlacionou-se positivamente com sua concentração, ou seja, quanto maior a concentração da solução de fermentação do farelo, melhor a capacidade de inibição estava. A solução de IC50 de fermentação de farelo foi de 9,23 mg / mL enquanto que, para comparação, a arbutina era de 0,52 mg / mL. Além disso, de acordo com o ensaio de sobrevivência celular, nenhum efeito citotóxico óbvio foi encontrado com o aumento da concentração da solução de fermentação de farelo. Quanto à avaliação do branqueamento, a taxa de branqueamento foi de 9,29% na diluição de 20%, 5,36% na diluição de 15%, 3,69% na diluição de 10%, 2,43% na diluição de 5%, 0,35% na diluição de 1% em um teste de 30 dias . Na avaliação hidratante, a taxa de melhora hidratante foi de 44,31% em 20% de diluição, 20,48% em diluição de 15%, 7,68% em diluição de 10%, 6,02% em diluição de 5% e 2,02% em diluição a 1%. Com base nos resultados experimentais, a solução de fermentação de farelo de arroz sem álcool não só não causou irritação, mas também teve anti-envelhecimento, inibição da síntese de melanina, branqueamento e efeitos hidratantes. Portanto, é aconselhável adicionar solução de fermentação de farelo de arroz para mousse de limpeza, gel de banho, soro e essência para transformar o farelo do composto de resíduos agrícolas (berço a túmulo) em uma matéria-prima natural (berço para berço) da indústria de cosméticos, criando Novo valor do farelo de arroz.


Assuntos
Bactérias , Eficácia , Ácido Láctico , Cosméticos , Fermentação
17.
Angew Chem Int Ed Engl ; 57(31): 9925-9929, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-29704400

RESUMO

Synthesis and characterization of two dodecacopper(I) extended metal atom chains (EMAC) assembled by two hexadentate bis(pyridylamido)amidinate-supported hexacopper(I) string complexes (monomers) via the ligand-unsupported cuprophilicity are described. In addition to short unsupported Cu-Cu contacts, two hexacopper fragments in these two dodecacopper EMACs show a bent conformation based on X-ray crystallography. Compared with their THF-bound hexacopper(I) monomers and protonated ligands, these ligand-unsupported cuprophilic interactions are shown to be weak by Raman spectroscopy. DFT calculations suggest the ligand-unsupported cuprophilicity originate from weak attractive orbital interactions, and the strength is estimated to be 2.4 kcal mol-1 .

18.
Inorg Chem ; 57(8): 4448-4455, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29600849

RESUMO

We developed a new method by enclosing the complex tris(2-phenylpyridinato-N,C2')Iridium(III), Ir(ppy)3 with surfactant cetyltrimethylammonium bromide (CATB), coated with a thin layer of silica then bonded to the surface of silver nanoparticle. These samples were used to acquire surface-enhanced Raman scattering (SERS) spectra. The thickness of silica layer was controlled to have efficient phosphorescence quenching and Raman enhancement by metal nanoparticle. The SERS spectra of fac- and mer-Ir(ppy)3, recorded at 633 nm excitation, display distinct ring breathing mode features because the total symmetric vibrational bands were enhanced. This provides a convenient means to differentiate these isomers with great sensitivity and to study their isomerization process. A direct conversion reaction of mer- to fac- isomerization is identified with time constant 3.1 min when mer was irradiated with Xe light. Via thermal activation, under moderate conditions (pH 5.5 and 343 K), we observed an intermediate particularly with new bands 320/662 cm-1 after heating for 17.5 h, and then those bands disappeared to form fac-Ir(ppy)3. On the basis of DFT calculations, the intermediate is proposed to contain octahedral N-N Ir(ppy)3-HO-silica structure; band at 320 cm-1 is assigned to iridium oxygen stretching mode νIr-O of this intermediate. Under acidic conditions, pH 1-2 catalyzed by silanol in silica, byproduct with band at 353 cm-1 was observed. According to the SERS bands and the calculation, this byproduct is assigned to be iridium(III) siloxide, and the new band is assigned to νIr-O.

19.
J Am Chem Soc ; 140(15): 5224-5234, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29587477

RESUMO

In this paper, we present a novel charge-free fluorescence-switchable near-infrared (IR) dye based on merocyanine for target specific imaging. In contrast to the typical bathochromic shift approach by extending π-conjugation, the bathochromic shift of our merocyanine dye to the near-IR region is due to an unusual S- cis diene conformer. This is the first example where a fluorescent dye adopts the stable S- cis conformation. In addition to the novel bathochromic shift mechanism, the dye exhibits fluorescence-switchable properties in response to polarity and viscosity. By incorporating a protein-specific ligand to the dye, the probes (for SNAP-tag and hCAII proteins) exhibited dramatic fluorescence increase (up to 300-fold) upon binding with its target protein. The large fluorescence enhancement, near-IR absorption/emission, and charge-free scaffold enabled no-wash and site-specific imaging of target proteins in living cells and in vivo with minimum background fluorescence. We believe that our unconventional approach for a near-IR dye with the S- cis diene conformation can lead to new strategies for the design of near-IR dyes.

20.
Phys Chem Chem Phys ; 19(37): 25471-25477, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28900646

RESUMO

Herein, the excited-state dynamics of an extended metal atom chain complex, Cr3(dpa)4Cl2 (dpa = dipyridylamide), in tetrahydrofuran solution were investigated using femtosecond transient absorption spectroscopy. Upon excitation at a wavelength of 330 nm, two distinct excited-state absorption species with varied dynamics were identified and assigned to the symmetric (s-) and unsymmetric (u-) Cr3(dpa)4Cl2. The major species is s-Cr3(dpa)4Cl2 that undergoes rapid conversion at less than 100 fs from the ligand-centred π-π* state, which is the initially accessed state, to the metal-centred d-d state and then vibrational cooling accompanying the structural relaxation at a time constant ∼2.2 ps. Most of the s-form is recovered to the ground state at ∼200 ps. For u-Cr3(dpa)4Cl2, a similar rapid conversion to d-d states is observed, and the geometric/vibrational relaxation is ∼0.8 ps. The second recovery of the ground state with approximately equal amplitude is observed at a time constant of ∼5 ns. This might be because many d-d states exist and about half of them inefficiently couple with the ground state surface.

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