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1.
Anal Chem ; 96(23): 9317-9324, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38818541

RESUMO

Inaccurate or cumbersome clinical pathogen diagnosis between Gram-positive bacteria (G+) and Gram-negative (G-) bacteria lead to delayed clinical therapeutic interventions. Microelectrode-based electrochemical sensors exhibit the significant advantages of rapid response and minimal sample consumption, but the loading capacity and discrimination precision are weak. Herein, we develop reversible fusion-fission MXene-based fiber microelectrodes for G+/G- bacteria analysis. During the fissuring process, the spatial utilization, loading capacity, sensitivity, and selectivity of microelectrodes were maximized, and polymyxin B and vancomycin were assembled for G+/G- identification. The surface-tension-driven reversible fusion facilitated its reusability. A deep learning model was further applied for the electrochemical impedance spectroscopy (EIS) identification in diverse ratio concentrations of G+ and G- of (1:100-100:1) with higher accuracy (>93%) and gave predictable detection results for unknown samples. Meanwhile, the as-proposed sensing platform reached higher sensitivity toward E. coli (24.3 CFU/mL) and S. aureus (37.2 CFU/mL) in 20 min. The as-proposed platform provides valuable insights for bacterium discrimination and quantification.


Assuntos
Microeletrodos , Bactérias Gram-Positivas/isolamento & purificação , Bactérias Gram-Negativas/isolamento & purificação , Escherichia coli/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Técnicas Eletroquímicas/instrumentação , Vancomicina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/análise , Polimixina B/química , Polimixina B/farmacologia , Espectroscopia Dielétrica
2.
J Colloid Interface Sci ; 660: 235-245, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38244492

RESUMO

Reactive oxygen species (ROS)-based therapy has emerged as a promising antibacterial strategy. However, it faces the limitations of uncontrollable space-time release and excessive lipid peroxidation, which may lead to a series of metabolic disorders and decreased immune function. In this study, mechanical damage by molybdenum oxide nanowires (MoOxNWs) is introduced as a synergistic factor to enhance the photothermal and photodynamic effects for controllable and efficient antibacterial therapy. Through their sharp ends, the nanowires can effectively pierce and damage the bacterial cells, thus facilitating the entry of externally generated ROS into the cells. The ROS are generated via photodynamic effect of the nanowires under a mere 5 min of near-infrared light irradiation. This approach enhances the photothermal (by 27.3 %) and photodynamic properties of ROS generation. MoOxNWs (100 µg·mL-1) achieve sterilisation rates of 97.67 % for extended-spectrum ß-lactamase-producing E. coli and 96.34 % for methicillin-resistant Staphylococcus aureus, which are comparable or even exceeding the efficacy of most MoOx-based antibacterial agents. Moreover, they exhibit good biocompatibility and low in vivo toxicity.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Fotoquimioterapia , Espécies Reativas de Oxigênio , Escherichia coli , Antibacterianos/farmacologia
3.
Anal Chim Acta ; 1291: 342225, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38280783

RESUMO

Endotoxin detection is important for determining bacterial contamination and infection in fields of food, pharmaceutical and clinical disease diagnosis. The horseshoe crab deformed cell lysate analysis is regarded as the gold-standard method, but the endangered and high-cost horseshoe crab animals required in sensing process further raise animal ethical issues and hinder their applications. The colorimetric methods based on nanozymes are simple and economical, but the low selectivity and sensitivity are still the bottleneck for their further application. Herein, we successfully developed a phenylboronic acid functionalized iron-based nanozyme with higher selectivity and highly catalytic activity for endotoxin sensing. The as-prepared colorimetric sensor using the obtained nanozyme as sensing probes shows a good linear relationship for endotoxin sensing in the range of 1-20 µg mL-1, with a LOD = 0.42 µg mL-1, along with good selectivity and reproducibility. The sensor can also be well applied to detecting endotoxin in practical samples such as beer and serum. Moreover, the parameters including time and temperature which could affect the endotoxin release from E. coli were also studied and optimized, based on the relationship between endotoxin and Gram-negative bacteria, the as-prepared sensor achieves the qualitative and quantification of E. coli.


Assuntos
Endotoxinas , Escherichia coli , Animais , Endotoxinas/análise , Reprodutibilidade dos Testes , Bactérias , Bactérias Gram-Negativas , Colorimetria
4.
Nanomaterials (Basel) ; 13(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36903792

RESUMO

Compared to the widely used compound semiconductor photoelectric sensors, all-silicon photoelectric sensors have the advantage of easy mass production because they are compatible with the complementary metal-oxide-semiconductor (CMOS) fabrication technique. In this paper, we propose an all-silicon photoelectric biosensor with a simple process and that is integrated, miniature, and with low loss. This biosensor is based on monolithic integration technology, and its light source is a PN junction cascaded polysilicon nanostructure. The detection device utilizes a simple refractive index sensing method. According to our simulation, when the refractive index of the detected material is more than 1.52, evanescent wave intensity decreases with the growth of the refractive index. Thus, refractive index sensing can be achieved. Moreover, it was also shown that, compared to a slab waveguide, the embedded waveguide designed in this paper has a lower loss. With these features, our all-silicon photoelectric biosensor (ASPB) demonstrates its potential in the application of handheld biosensors.

5.
Thorac Cancer ; 13(22): 3192-3199, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36178200

RESUMO

BACKGROUND: To assess the effectiveness and safety of laryngeal mask anesthesia (LMA) in thoracoscopic pulmonary wedge resection based on patient-reported outcomes (PROs). METHODS: This randomized controlled trial included 107 patients who underwent thoracoscopic pulmonary wedge resection between June 2017 and December 2021 for pulmonary nodule or pulmonary bullae. In one group, LMA was applied for general anesthesia, and in the other group, endotracheal intubation (ETT) was used. RESULTS: A total of 107 patients were included in the study. The symptom assessment based on PROs showed that the incidence of pharyngodynia, trachyphonia, and cough were lower in the LMA group, while the postoperative gastrointestinal reaction did not significantly differ between the two groups. The pain score and global satisfaction score were significantly better in the LMA group. The satisfaction degree of anesthesia and the surgical field did not significantly differ between the two groups. The anesthesia recovery time, indwelling days of chest catheter, and postoperative hospital stay of the LMA group were all shorter, while the operation time, intraoperative blood loss and lowest intraoperative oxygen saturation did not significantly differ between the two groups. The highest intraoperative partial pressure of CO2 was significantly higher in the LMA group. The artery blood gas analysis after the operation did not significantly differ between the two groups. CONCLUSION: Compared with ETT, the application of LMA may demonstrate promising advantages in airway management for thoracoscopic pulmonary wedge resection. REGISTRATION NO: of clinical trial (ChiCTR2000034905).


Assuntos
Máscaras Laríngeas , Pneumopatias , Humanos , Intubação Intratraqueal , Anestesia Geral , Medidas de Resultados Relatados pelo Paciente
6.
Biosens Bioelectron ; 210: 114272, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35477151

RESUMO

The high morbidity and mortality of bladder cancer highlights the need of cancer risk prediction, which can be achieved by the analysis of the related DNA mutations. The facile, low-cost colorimetric methods were promising but still suffered from low sensitivity or poor selectivity. Therefore, highly active colorimetric probes and DNA/signal amplification technologies are still in urgent need to be explored. Herein, a bimetallic nanozyme Fe2MoO4 NPs with excellent peroxidase-like activity were successfully synthesized as the colorimetric probe, combining with hybridization chain reaction (HCR) to analyze the PSCA rs2294008 (C > T) as a factor for risk prediction of bladder cancer. The absorbance variation and selectivity can then be amplified upon the HCR, which could lead to prolonged DNA length beyond the range of •OH action and double chain with more negative charge to occupy more TMB while repelling the negatively charged nanozyme. Under the optimized conditions, the as-proposed method can achieve sensitive detection of the DNA mutation in the concentration range of 25 pM to 4 nM and detection limit as low as 2 pM, which is superior or comparable to most previously reported colorimetric sensors. Moreover, the practicability of the sensor was verified via the application in serum samples, showing satisfactory accuracy and good reproducibility.


Assuntos
Técnicas Biossensoriais , Neoplasias da Bexiga Urinária , Técnicas Biossensoriais/métodos , Colorimetria/métodos , DNA , Humanos , Reprodutibilidade dos Testes , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética
7.
Zhongguo Fei Ai Za Zhi ; 24(10): 690-697, 2021 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-34628780

RESUMO

BACKGROUND: With the extensive development of minimally invasive surgery for pulmonary nodules, preoperative localization becomes more and more critical. There are some defects in traditional localization methods, so it is necessary to improve. The aim of this study was to compare and analyze the safety and effectiveness of two new methods, namely four-hook needle and memory alloy coil, in the localization of pulmonary nodules. METHODS: A retrospective analysis of 152 patients was performed. 76 cases were in four-hook needle group, and 76 cases were in memory alloy coil group. Pulmonary nodules were located before operation, and then video-assisted wedge resection was performed. The average procedure time, localization complications and nodule resection time were counted. RESULTS: The target pulmonary nodules were successfully removed in both groups. In four-hook needle group, 76 patients found localization devices, all the pulmonary nodules were successfully removed, and one case was transferred to open the chest for wedge resection of pulmonary nodules due to severe thoracic adhesion. All 76 patients in memory alloy coil group were successfully resected with pulmonary nodules, and one patient underwent compromising enlarged resection because no lesion was found after the specimen was removed during the operation. There was no significant difference in the incidence of pneumothorax and pulmonary hemorrhage, the success rate of localization and nodule wedge resection time between the two groups. The average time of localization in four-hook needle group was (13.66±3.11) min, lower than that of memory alloy coil group (15.51±3.65) min, and the difference was statistically significant (P=0.001). In memory alloy coil group, when the distance from the nodule to the pleura was ≥1.5 cm and <1.5 cm, the average localization time was (17.20±4.46) min and (14.91±3.15) min, respectively, and there was a statistical difference between the two distance (P=0.044). CONCLUSIONS: Four-hook needle and memory alloy coil have good safety and effectiveness, and the localization time of four-hook needle is shorter. When using memory alloy coil, the effect of the method is better for pulmonary nodules with a distance less than 1.5 cm to pleura.


Assuntos
Nódulos Pulmonares Múltiplos , Ligas , Humanos , Neoplasias Pulmonares/cirurgia , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida , Tomografia Computadorizada por Raios X
8.
Carbohydr Polym ; 254: 117286, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357859

RESUMO

Dimethyl sulfoxide (DMSO) is an excellent solvent for various types of anticancer drugs. Here, beyond that, it can participate in a disulfide bond crosslink between sulfhydryl (-SH) modified hyaluronic acid (HA-SH) molecules to form the hydrogel. Thus, during the above crosslink process, the dissolved drug in DMSO could be effectively loaded inside the hydrogels' porous structures as an injectable peritumoral implant. The loaded drugs can be sustained released through hydrogel swelling and degradation around the tumor tissue to suppress tumor growth. In this paper, the above hydrogel was used as a peritumoral drug-loaded implant for chemotherapeutics, photosensitizer, and photothermal reagent, respectively, for chemotherapy, photodynamic therapy, and photothermal therapy in cancer treatment. Therefore, this DMSO involved HA-SS-HA (HA, hyaluronic acid; -SS-, disulfide bond) hydrogel fabrication method is simple and widely applicable for drug-loaded peritumoral implant preparation.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Ácido Hialurônico/química , Hidrogéis/administração & dosagem , Hidrogéis/química , Injeções/métodos , Compostos de Sulfidrila/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas/química , Dimetil Sulfóxido/química , Modelos Animais de Doenças , Feminino , Células HeLa , Humanos , Hidrogéis/síntese química , Camundongos , Camundongos Endogâmicos BALB C , Porosidade , Solventes/química , Temperatura , Carga Tumoral/efeitos dos fármacos
9.
Sci Technol Adv Mater ; 21(1): 689-711, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33177953

RESUMO

Low temperature solder (In-based, Sn-Bi, Sn-Zn) has great advantages in aerospace and through-hole technology assemblies in IBM mainframe due to its unique low temperature characteristics. The review evaluates the effects of alloying elements, rare earth elements and nanoparticles on the wettability, microstructure, mechanical properties and oxidation resistance of the low-temperature solders.

10.
Thorac Cancer ; 11(11): 3388-3390, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32986288

RESUMO

Lymphangiomatosis is a rare, benign, hyperproliferative hamartoma composed of dilated lymphatic vessels. Cystic lymphangioma (CL) in the chest wall in an adult patient is rare, but we focus on this type of patient in our present case study. A 54-year-old female patient with a painless mass in her chest wall went without treatment for two years following diagnosis. After consenting to treatment, Doppler color flow imaging (DCFI), chest CT, and MRI revealed a cystic lesion with multiple thin septula in the left chest. Surgical resection was performed, and histopathological examination identified a cystic lymphangioma. The patient did not experience recurrence during the follow-up period.


Assuntos
Linfangioma Cístico/diagnóstico , Parede Torácica/patologia , Feminino , Humanos , Linfangioma Cístico/patologia , Pessoa de Meia-Idade
11.
ACS Biomater Sci Eng ; 6(1): 450-462, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33463237

RESUMO

The tumor microenvironment (TME) is composed of tumor cells, blood vessels, cancer-associated fibroblasts (CAFs), tumor extracellular matrix (ECM), et al. The TME is closely related to anticancer treatment outcome. In this manuscript, a multifunctional nanomedicine (denoted as ZDCMH NP), combining multiple TME destruction strategies into one delivery system, has been designed and fabricated. In brief, zinc phthalocyanine (ZnPc, a photosensitizer), bromopentacarbonylmanganese(I) (COMn, a CO donor), and losartan (Dup, a CAF inhibitor) were coloaded inside mesoporous silica nanoparticles (MSNs). After that, a cross-linked hyaluronic acid (HA) gel shell was encapsulated onto the surface of the MSNs to form ZDCMH NPs. After arriving at the tumor tissue, the HA gel shell could be degraded by hyaluronidase (HAase) in the ECM to trigger encapsulated drug release. After light irradiation, ZnPc generated abundant reactive oxygen species (ROS), which could provide photodynamic therapy (PDT) activity and induce COMn to release CO, which could improve the enhanced permeability and retention (EPR) effect to promote ZDCMH NP accumulation in tumor tissue. The released Dup could inhibit CAF activity and downregulate the collagen fiber concentration in the TME to promote the deep penetration of ZDCMH NPs inside solid tumors. In vitro and in vivo anticancer studies have indicated that the destruction of the TME by multiple strategies is very helpful for ZnPc to obtain satisfactory PDT efficiency.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Microambiente Tumoral
12.
Thorac Cancer ; 10(2): 352-358, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30548923

RESUMO

A preoperative chest computed tomography examination of the right breast in a 52-year-old woman with breast cancer revealed multiple nodules in both lungs. The nodule in the apical segment of the upper lobe of the right lung was larger, at a diameter of approximately 2.1 cm. The patient underwent resection of the right breast, followed by thoracoscopic wedge resection of four pulmonary nodules. Hematoxylin and eosin staining and immunohistochemistry showed that the nodules in the apical and anterior segments of the upper lobe and the paravertebral nodule in the lower lobe of the right lung were primary adenocarcinoma, and the subpleural nodule in the lower lobe of the right lung was infiltrated with inflammatory cells. Exon sequencing was conducted in the resected tissue samples and blood specimens. According to the characteristics of the somatic mutations, the nodule in the apical segment of the upper lobe of the right lung was primary lung adenocarcinoma, the nodule in the anterior segment of the upper lobe and the paravertebral nodule in the lower lobe of the right lung were intrapulmonary metastatic cancer, and the subpleural nodule in the lower lobe of the right lung indicated early stage tumor progression. This case provides new evidence that conducting gene detection in multiple tissue samples from patients who have undergone resection may assist to determine the relationship among multiple nodules in the lung to exclude lung metastasis of breast cancer.


Assuntos
Adenocarcinoma de Pulmão/secundário , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Nódulos Pulmonares Múltiplos/patologia , Nódulo Pulmonar Solitário/patologia , Adenocarcinoma de Pulmão/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Linfonodos/cirurgia , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/cirurgia , Prognóstico , Nódulo Pulmonar Solitário/cirurgia , Taxa de Sobrevida
13.
Free Radic Biol Med ; 124: 431-446, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-29981371

RESUMO

In photodynamic therapy (PDT), the elevated glutathione (GSH) of cancer cells have two sides for treatment efficacy, activation pre-drug by removing activity suppressor part (advantages) and consumption reactive oxygen species (ROS) to confer PDT resistance (disadvantages). Preparation all-in-one system by simple method to make best use of the advantages and bypass the disadvantages still were remains a technical challenge. Herein, we report a robust PDT nanoparticle with above function based on a self-assembled pyridine modified Zinc phthalocyanine (ZnPc-DTP). The activity suppressor and active part of ZnPc-DTP were linked by disulfide bond. After targeting cancer cells, GSH can react with ZnPc-DTP nanoparticles by cutting disulfide bond to release its active part (ZnPc-SH) and oxidize GSH. In vitro and in vivo results indicated that ZnPc-SH can effective suppress tumor growth under the low antioxidant tumor microenvironment (TME).


Assuntos
Antioxidantes/farmacologia , Glutationa/efeitos dos fármacos , Indóis/farmacologia , Nanopartículas/química , Compostos Organometálicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Humanos , Isoindóis , Fotoquimioterapia/métodos , Compostos de Zinco
14.
Chemistry ; 24(50): 13205-13212, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-29878461

RESUMO

Organic micro- and nanostructures are expected to be promising candidates for micro- and nanophotonic materials with desirable properties owing to their low cost, flexible molecular design, and tunable self-assembly. Among these candidates, well-known squaraine dyes (SQs) have rarely been investigated because of their nonfluorescent properties in the solid state and because their optical behavior varies with changes in morphology. In this contribution, two novel 1,2-SQs, SQM and SQB, with strong bright-yellow to red fluorescence emission in the crystalline state, were designed and structured at the molecular level and by solvent adjustment. Their self-assembly behavior was studied, and it was revealed that the SQM assembly provided 1D microrods, whereas 1D microrods (Z-SQB⋅CH2 Cl2 ) and 2D microplates (E-SQB⋅2 CH3 OH) could be obtained from SQB assemblies through a solution-based self-assembly method. The varied assembly behaviors of these SQs were attributed to different π-π stacking interactions that resulted in different molecular conformations and packing modes. These assemblies exhibited distinct optical properties, and in particular, SQB⋅solvent assemblies showed multiple thermo- and vapochromic effects. Thus, the SQB assemblies are potential fluorescent sensors for organic solvent vapors. More importantly, favorable optical-waveguide properties were observed in these SQ-based microstructures.

15.
Thorac Cancer ; 9(7): 874-876, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29718593

RESUMO

An ectopic meningioma, such as a primary pulmonary meningioma (PPM), is a rare type of tumor that primarily originates outside of the central nervous system. A 65-year-old female patient underwent a thoracoscopic lung wedge resection of the right lower lobe for a micro solid nodule detected via computed tomography. The histologic result revealed a PPM. PPMs manifested with micro solid nodules are a very rare occurrence in clinical practice. Increased awareness of the clinical and pathological characteristics of this rare disease can assist thoracic surgical teams to apply adequate management.


Assuntos
Neoplasias Pulmonares/diagnóstico , Pulmão/diagnóstico por imagem , Meningioma/diagnóstico , Nódulo Pulmonar Solitário/diagnóstico , Idoso , Feminino , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Meningioma/diagnóstico por imagem , Meningioma/patologia , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/patologia , Tomografia Computadorizada por Raios X
16.
Appl Opt ; 56(31): NIR1-NIR2, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29091670

RESUMO

This feature issue reports on the most recent advances in the field of III-V semiconductor lasers emitting in the near- to mid-IR spectral regions, with a particular focus on devices with an emission wavelength range between 1 and 13 µm.

17.
Dalton Trans ; 46(33): 10780-10785, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28762413

RESUMO

Two dimensional (2D) metalloporphyrin-based covalent organic framework (COF) composites were synthesized and employed to catalyze the coupling of CO2 and epoxides to form cyclic carbonates. With the aid of a co-catalyst, a satisfactory selectivity (∼100%) and activity (99.2%) for the synthesis of 1,2-butylene carbonate were obtained on COF-366-Zn under mild reaction conditions. Their great recyclability and adaptability for various substrates were also demonstrated. The excellent performance may be benefited from their unique 2D COF structure and the facilitation effects on central metalloporphyrin sites from the internal environment of COFs.

18.
Inorg Chem ; 55(3): 1258-69, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26756374

RESUMO

As active site models of [Fe]-hydrogenase, tridentate 2-acylmethyl-6-methoxymethoxy-difunctionalized pyridine-containing complexes η(3)-(2-COCH2-6-MeOCH2OC5H3N)Fe(CO)2(L1) (4, L1 = I; 5, SCN; 6, PhCS2) were prepared via the following multistep reactions: (i) etherification of 2-MeO2C-6-HOC5H3N with ClCH2OMe to give 2-MeO2C-6-MeOCH2OC5H3N (1), (ii) reduction of 1 with NaBH4 to give 2-HOCH2-6-MeOCH2OC5H3N (2), (iii) esterification of 2 with 4-toluenesulfonyl chloride to give 2-TsOCH2-6-MeOCH2OC5H3N (3), (iv) nucleophilic substitution of 3 with Na2Fe(CO)4 followed by treatment of the resulting Fe(0) intermediate Na[(2-CH2-6-MeOCH2OC5H3N)Fe(CO)4] (M1) with I2 to give complex 4, and (v) condensation of 4 with KSCN and PhCS2K to give complexes 5 and 6, respectively. In contrast to the preparation of complexes 4-6, bidentate 2-acylmethyl-6-methoxymethoxy-difunctionalized pyridine-containing model complexes η(2)-(2-COCH2-6-MeOCH2OC5H3N)Fe(CO)2(I)(L2) (7, L2 = PPh3; 8, Cy-C6H11NC) and η(2)-(2-COCH2-6-MeOCH2OC5H3N)Fe(CO)2(L3) (9, L3 = 2-SC5H4N; 10, 8-SC9H6N) were prepared by ligand exchange reactions of 4 with PPh3, Cy-C6H11NC, 2-KSC5H4N, and 8-KSC9H6N, respectively. Particularly interesting is that the tridentate 2,6-bis(acylmethyl)pyridine- and 2-acylmethyl-6-arylthiomethylpyridine-containing model complexes η(3)-[2,6-(COCH2)2C5H3N]Fe(CO)2(L4) (11, L4 = PPh3; 12, CO) and η(3)-2-(COCH2-6-ArSCH2C5H3N)Fe(CO)2(ArS) (13, ArS = PhS; 14, 2-S-5-MeC4H2O) were obtained, unexpectedly, when 2,6-(TsOCH2)2C5H3N reacted with Na2Fe(CO)4 followed by treatment of the resulting mixture with ligands PPh3 and CO or disulfides (PhS)2 and (2-S-5-MeC4H2O)2. Reactions of ligand precursors 3 and 2,6-(TsOCH2)2C5H3N with Na2Fe(CO)4 were monitored by in situ IR spectroscopy, and the possible pathways for producing complexes 4 and 11-14 via intermediates Na[(2-CH2-6-MeOCH2OC5H3N)Fe(CO)4] (M1), Na[(2-CH2-6-TsOCH2C5H3N)Fe(CO)4] (M2), and (2-COCH2-6-CH2C5H3N)Fe(CO)3 (M3) are suggested. New compounds 1-14 were characterized by elemental analysis, spectroscopy, and, for some of them, X-ray crystallography.


Assuntos
Hidrogenase/química , Compostos de Ferro/síntese química , Proteínas Ferro-Enxofre/química , Hidrogenase/metabolismo , Compostos de Ferro/química , Compostos de Ferro/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Ligantes , Modelos Moleculares , Conformação Molecular , Estrutura Molecular
19.
Appl Opt ; 54(21): 6420-4, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26367823

RESUMO

In this paper, we discuss the emission of visible light by a monolithically integrated silicon gate-controlled diode with the p-n junction reverse-biased. Since the MOS-like diode utilizes the field effect to modulate the optical output, the modulation speed will benefit from this mechanism. Hence, a silicon gate-controlled diode structure for optical modulation analyzed its modulation principle, its dynamic characteristics are presented, and the bandwidth of the device is considered to approach GHz in theory due to the field-induced emission mechanism. The prototype MOS-like diode opens up the design of multiterminal silicon light emitting devices (LEDs), where gate electrodes with more than one gate contact overlap several junctions with different junction intersection geometries. The device appears as a good candidate for optical modulation within silicon technology.

20.
Leg Med (Tokyo) ; 17(4): 287-94, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25759193

RESUMO

The two hypervariable segments (HVS-I and HVS-II) of mitochondrial DNA (mtDNA) control region were sequenced for a population of 208 unrelated healthy individuals sampled from Suiping County, Henan Province, China. A total of 192 different haplotypes were identified, of which 179 haplotypes were unique (93.23%). The variation of the mtDNA HVS-I and HVS-II was confined to 166 nucleotide positions, of which 115 were observed in the HVS-I and 51 in the HVS-II. The haplotype diversity and random match probability were 0.9991 and 0.0061, respectively. Following the principle of the updated East Asian mtDNA phylogeny tree, individual samples were assigned to the specific haplogroups based on the information both from control region and coding-region obtained. Haplogroup D was the most common haplogroup (25.96%). The northern China-prevalent haplogroups (A, C, D, G, M8, Y, and Z) and the southern China-prevalent haplogroups (B, F, M7, N9, and R9) accounted for 48.56% and 46.63%, respectively, of the Henan Han mtDNA gene pool. The mtDNA hypervariable region was highly polymorphic in Henan Han population. These sequences could serve as mtDNA reference data for forensic casework in Henan population as well as for population genetic study.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Etnicidade/genética , Variação Genética , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA , China , Haplótipos , Humanos
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