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1.
Small ; 20(26): e2308861, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38372029

RESUMO

The anabolism of tumor cells can not only support their proliferation, but also endow them with a steady influx of exogenous nutrients. Therefore, consuming metabolic substrates or limiting access to energy supply can be an effective strategy to impede tumor growth. Herein, a novel treatment paradigm of starving-like therapy-triple energy-depleting therapy-is illustrated by glucose oxidase (GOx)/dc-IR825/sorafenib liposomes (termed GISLs), and such a triple energy-depleting therapy exhibits a more effective tumor-killing effect than conventional starvation therapy that only cuts off one of the energy supplies. Specifically, GOx can continuously consume glucose and generate toxic H2O2 in the tumor microenvironment (including tumor cells). After endocytosis, dc-IR825 (a near-infrared cyanine dye) can precisely target mitochondria and exert photodynamic and photothermal activities upon laser irradiation to destroy mitochondria. The anti-angiogenesis effect of sorafenib can further block energy and nutrition supply from blood. This work exemplifies a facile and safe method to exhaust the energy in a tumor from three aspects and starve the tumor to death and also highlights the importance of energy depletion in tumor treatment. It is hoped that this work will inspire the development of more advanced platforms that can combine multiple energy depletion therapies to realize more effective tumor treatment.


Assuntos
Glucose Oxidase , Lipossomos , Sorafenibe , Lipossomos/química , Humanos , Glucose Oxidase/metabolismo , Glucose Oxidase/química , Animais , Sorafenibe/farmacologia , Linhagem Celular Tumoral , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Metabolismo Energético , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/química , Indóis
2.
J Transl Med ; 22(1): 6, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167440

RESUMO

BACKGROUND: Tandem C2 domains, nuclear (TC2N) is a C2 domain-containing protein that belongs to the carboxyl-terminal type (C-type) tandem C2 protein family, and acts as an oncogenic driver in several cancers. Previously, we preliminarily reported that TC2N mediates the PI3K-Akt signaling pathway to inhibit tumor growth of breast cancer (BC) cells. Beyond that, its precise biological functions and detailed molecular mechanisms in BC development and progression are not fully understood. METHODS: Tumor tissues of 212 BC patients were subjected to tissue microarray and further assessed the associations of TC2N expression with pathological parameters and FASN expression. The protein levels of TC2N and FASN in cell lines and tumor specimens were monitored by qRT-PCR, WB, immunofluorescence and immunohistochemistry. In vitro cell assays, in vivo nude mice model was used to assess the effect of TC2N ectopic expression on tumor metastasis and stemness of breast cancer cells. The downstream signaling pathway or target molecule of TC2N was mined using a combination of transcriptomics, proteomics and lipidomics, and the underlying mechanism was explored by WB and co-IP assays. RESULTS: Here, we found that the expression of TC2N remarkedly silenced in metastatic and poorly differentiated tumors. Function-wide, TC2N strongly inhibits tumor metastasis and stem-like properties of BC via inhibition of fatty acid synthesis. Mechanism-wise, TC2N blocks neddylated PTEN-mediated FASN stabilization by a dual mechanism. The C2B domain is crucial for nuclear localization of TC2N, further consolidating the TRIM21-mediated ubiquitylation and degradation of FASN by competing with neddylated PTEN for binding to FASN in nucleus. On the other hand, cytoplasmic TC2N interacts with import proteins, thereby restraining nuclear import of PTEN to decrease neddylated PTEN level. CONCLUSIONS: Altogether, we demonstrate a previously unidentified role and mechanism of TC2N in regulation of lipid metabolism and PTEN neddylation, providing a potential therapeutic target for anti-cancer.


Assuntos
Neoplasias da Mama , Animais , Camundongos , Humanos , Feminino , Neoplasias da Mama/patologia , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Ácidos Graxos , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , PTEN Fosfo-Hidrolase/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica
3.
Langmuir ; 40(17): 9082-9096, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38619979

RESUMO

Great efforts have been devoted to the development of novel and multifunctional wound dressing materials to meet the different needs of wound healing. Herein, we covalently grafted quaternary ammonium groups (QAGs) containing 12-carbon straight-chain alkanes to the dextran polymer skeleton. We then oxidized the resulting product into oxidized quaternized dextran (OQD). The obtained OQD polymer is rich in antibacterial QAGs and aldehyde groups. It can react with glycol chitosan (GC) via the Schiff-base reaction to form a multifunctional GC@OQD hydrogel with good self-healing behavior, hemostasis, injectability, inherent superior antibacterial activity, biocompatibility, and excellent promotion of healing of methicillin-resistant Staphylococcus aureus (MRSA)-infected wounds. The biosafe and nontoxic GC@OQD hydrogel with a three-dimensional porous network structure possesses an excellent swelling rate and water retention capacity. It can be used for hemostasis and treating irregular wounds. The designed GC@OQD hydrogel with inherent antibacterial activity possesses good antibacterial efficacy on both S. aureus (Gram-positive bacteria) and Escherichia coli (Gram-negative bacteria), as well as MRSA bacteria, with antibacterial activity greater than 99%. It can be used for the treatment of wounds infected by MRSA and significantly promotes the healing of wounds. Thus, the multifunctional antibacterial GC@OQD hydrogel has the potential to be applied in clinical practice as a wound dressing.


Assuntos
Antibacterianos , Quitosana , Escherichia coli , Hidrogéis , Staphylococcus aureus Resistente à Meticilina , Cicatrização , Hidrogéis/química , Hidrogéis/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Animais , Quitosana/química , Quitosana/farmacologia , Dextranos/química , Dextranos/farmacologia , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Camundongos , Polissacarídeos/química , Polissacarídeos/farmacologia
4.
Eur Arch Otorhinolaryngol ; 281(3): 1425-1434, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37995006

RESUMO

OBJECTIVE: To analyze the interrelation between radiation dose and radiation-induced nasopharyngeal ulcer (RINU) in locoregional recurrent nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). METHODS: Clinical data were collected from 363 patients with locoregional recurrent NPC who received re-irradiated with definitive IMRT from 2009 to 2017. Twenty-nine patients were diagnosed with RINU. Univariate and multivariate analyses were used to re-evaluate the first and second radiotherapy plans and to identify predictive dosimetric factors. RESULTS: All dosimetric parameters were notably associated with the progression to RINU (p < 0.01) using paired samples Wilcoxon signed rank tests. Multivariate analysis showed that EQD2_ [Formula: see text]D80 (dose for 80 percent volume of the unilateral nasopharynx lesion) was an independent prognostic factor for RINU (p = 0.001). The area under the ROC curve for EQD2_ [Formula: see text]D80 was 0.846 (p < 0.001), and the cutoff point of 137.035 Gy could potentially be the dose tolerance of the nasopharyngeal mucosa. CONCLUSIONS: The sum of equivalent dose in 2 Gy fractions (EQD2) in the overlapping volumes between initial and re-irradiated nasopharyngeal mucosal tissue can be effective in predicting the hazard of developing RINU in NPC patients undergoing radical re­irradiation with IMRT and we propose a EQD2_ [Formula: see text]D80 threshold of 137.035 Gy for the nasopharynx.


Assuntos
Neoplasias Nasofaríngeas , Lesões por Radiação , Radiodermite , Radioterapia de Intensidade Modulada , Reirradiação , Humanos , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Neoplasias Nasofaríngeas/patologia , Úlcera/etiologia , Dosagem Radioterapêutica , Lesões por Radiação/etiologia , Estudos Retrospectivos , Nasofaringe/patologia , Radiodermite/etiologia
5.
Sensors (Basel) ; 24(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38732786

RESUMO

CO2 monitoring is important for carbon emission evaluation. Low-cost and medium-precision sensors (LCSs) have become an exploratory direction for CO2 observation under complex emission conditions in cities. Here, we used a calibration method that improved the accuracy of SenseAir K30 CO2 sensors from ±30 ppm to 0.7-4.0 ppm for a CO2-monitoring instrument named the SENSE-IAP, which has been used in several cities, such as in Beijing, Jinan, Fuzhou, Hangzhou, and Wuhan, in China since 2017. We conducted monthly to yearly synchronous observations using the SENSE-IAP along with reference instruments (Picarro) and standard gas to evaluate the performance of the LCSs for indoor use with relatively stable environments. The results show that the precision and accuracy of the SENSE-IAP compared to the standard gases were rather good in relatively stable indoor environments, with the short-term (daily scale) biases ranging from -0.9 to 0.2 ppm, the root mean square errors (RMSE) ranging from 0.7 to 1.6 ppm, the long-term (monthly scale) bias ranging from -1.6 to 0.5 ppm, and the RMSE ranging from 1.3 to 3.2 ppm. The accuracy of the synchronous observations with Picarro was in the same magnitude, with an RMSE of 2.0-3.0 ppm. According to our evaluation, standard instruments or reliable standard gases can be used as a reference to improve the accuracy of the SENSE-IAP. If calibrated daily using standard gases, the bias of the SENSE-IAP can be maintained within 1.0 ppm. If the standard gases are hard to access frequently, we recommend a calibration frequency of at least three months to maintain an accuracy within 3 ppm.

6.
J Environ Sci (China) ; 139: 377-388, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105063

RESUMO

Atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter, for which the reason have not been clearly elucidated. Here we measured carbonyl compounds and other trace gasses together with PM2.5 over urban Jinan in North China Plain during the winter. Markedly higher carbonyl concentrations (average: 14.63 ± 4.21 ppbv) were found during wintertime haze pollution, about one to three-times relative to those on non-haze days, with slight difference in chemical composition except formaldehyde (HCHO). HCHO (3.68 ppbv), acetone (3.17 ppbv), and acetaldehyde (CH3CHO) (2.83 ppbv) were the three most abundant species, accounting for ∼75% of the total carbonylson both haze and non-haze days. Results from observational-based model (OBM) with atmospheric oxidation capacity (AOC) indicated that AOC significantly increased with the increasing carbonyls during the winter haze events. Carbonyl photolysis have supplied key oxidants such as RO2 and HO2, and thereby enhancing the formation of fine particles and secondary organic aerosols, elucidating the observed haze-carbonyls inter-correlation. Diurnal variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources. 1-butene was further confirmed to be the major precursor for HCHO. This study confirms the great contribution of carbonyls to AOC, and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , China , Material Particulado/análise , Estações do Ano , Acetaldeído/análise , Monitoramento Ambiental , Aerossóis/análise
7.
Angew Chem Int Ed Engl ; 63(5): e202315300, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38085965

RESUMO

Photocatalytic CO2 reduction is one of the best solutions to solve the global energy crisis and to realize carbon neutralization. The tetradentate phosphine-bipyridine (bpy)-phosphine (PNNP)-type Ir(III) photocatalyst, Mes-IrPCY2, was reported with a high HCOOH selectivity but the photocatalytic mechanism remains elusive. Herein, we employ electronic structure methods in combination with radiative, nonradiative, and electron transfer rate calculations, to explore the entire photocatalytic cycle to either HCOOH or CO, based on which a new mechanistic scenario is proposed. The catalytic reduction reaction starts from the generation of the precursor metal-to-ligand charge transfer (3 MLCT) state. Subsequently, the divergence happens from the 3 MLCT state, the single electron transfer (SET) and deprotonation process lead to the formation of one-electron-reduced species and Ir(I) species, which initiate the reduction reaction to HCOOH and CO, respectively. Interestingly, the efficient occurrence of proton or electron transfer reduces barriers of critical steps. In addition, nonadiabatic transitions play a nonnegligible role in the cycle. We suggest a lower free-energy barrier in the reaction-limiting step and the very efficient SET in 3 MLCT are cooperatively responsible for a high HCOOH selectivity. The gained mechanistic insights could help chemists to understand, regulate, and design photocatalytic CO2 reduction reaction of similar function-integrated molecular photocatalyst.

8.
Phys Chem Chem Phys ; 25(8): 6454-6460, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36779957

RESUMO

One recent experimental study reported a Ir(III) complex with thermally activated delayed fluorescence (TADF) phenomenon in solution, but its luminescent mechanism is elusive. In this work, we combined density functional theory (DFT), time-dependent DFT (TDDFT) and multi-state complete active space second-order perturbation theory (MS-CASPT2) methods to investigate excited-state properties, photophysics, and emission mechanism of this Ir(III) complex. Two main absorption bands observed in experiments can be attributed to the electronic transition from the S0 state to the S1 and S2 states; while, the fluorescence and phosphorescence are generated from the S1 and T1 states, respectively. Both the S1 and T1 states have clear metal-to-ligand charge transfer (MLCT) character. The present computational results reveal a three-state model including the S0, S1 and T1 states to rationalize the TADF behavior. The small energy gap between the S1 and T1 states benefits the forward and reverse intersystem crossing (ISC and rISC) processes. At 300 K, the rISC rate is five orders of magnitude larger than the phosphorescence rate therefore enabling TADF. At 77 K, the rISC rate is sharply decreased but remains close to the phosphorescence rate; therefore, in addition to the phosphorescence, the delayed fluorescence could also contribute to the experimental emission. The estimated TADF lifetime agrees well with experiments, 9.80 vs. 6.67 µs, which further verifies this three-state model.

9.
Environ Res ; 238(Pt 1): 117158, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37726031

RESUMO

Volatile organic compounds (VOCs) undergo substantial photochemical losses during their transport from emission sources to receptor sites, resulting in serious implications for their source apportionment and ozone (O3) formation. Based on the continuous measurements of VOCs in suburban Jinan in August 2022, the effects of photochemical losses on VOC source contributions and O3 formation were evaluated in this study. The observed and initial concentrations of total VOCs (TVOC) were 12.0 ± 5.1 and 16.0 ± 7.4 ppbv, respectively. Throughout the observation period, alkenes had the most prominent photochemical losses (58.2%), followed by aromatic hydrocarbons (23.1%), accounting for 80.6% and 6.9% of the total losses, respectively. During high O3 episodes, the photochemical loss of VOCs was 6.9 times higher than that during the cleaning period. Alkene losses (exceeding 67.3%), specifically losses of isoprene, propylene, ethylene, and n-butene, dominated the total losses of VOCs during the O3 increase period. Eight sources of VOCs were identified by positive matrix factorization (PMF) based on the observed and initial concentration data (OC-PMF and IC-PMF, respectively). Concentrations of all emission sources in the OC-PMF were underestimated by 2.4%-57.1%. Moreover, the contribution of each emission source was over- or underestimated compared with that in case of the IC-PMF. The contributions of biogenic and motor vehicle exhaust emissions were underestimated by 5.3 and 2.8 percentage points, respectively, which was associated with substantial oxidation of the emitted high-reactive species. The contributions of coal/biomass burning and natural gas were overestimated by 2.4 and 3.9 percentage points, respectively, which were related to the emission of low-reactive species (acetylene, ethane, and propane). Based on our results, the photochemical losses of VOCs grossly affect their source apportionment and O3 formation. Thus, photochemical losses of VOCs must be thoroughly accounted to establish a precise scientific foundation for air-pollution control strategies.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Ozônio/análise , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , China , Emissões de Veículos/análise , Monitoramento Ambiental
10.
BMC Cancer ; 22(1): 1083, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271328

RESUMO

BACKGROUND: To review our long-term clinical experience, analyze the failure patterns, and give suggestions for target volume delineation of carcinoma showing thymus-like differentiation (CASTLE) treated with intensity-modulated radiotherapy (IMRT). METHODS: From April 2008 to May 2019, 30 patients with CASTLE treated by postoperative or radical IMRT in our center were retrospectively reviewed. A total dose of 56-60 Gy in 28-30 fractions was prescribed to patients without residual disease and 66 Gy in 33 fractions for patients with residual or unresectable disease. Survival rates were calculated using the Kaplan-Meier method. Treatment-related toxicities were graded by National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 4.0. RESULTS: Among the 30 patients, 12 (40%) received partial resection or biopsy. Lateral lymph node metastasis was observed in 7 (23.3%) patients. During follow-up, regional lymph node recurrence occurred in 2 patients and distant metastasis in 5 patients. With a median follow-up time of 63.5 months, the 5-year local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS), overall survival (OS) and progression-free survival (PFS) rates were 100, 88.9, 78.9, 93.1 and 78.9%, respectively. For patients with no lateral neck node metastasis, prophylactic radiotherapy for lateral neck nodal regions failed to improve RRFS (p = 0.381) and OS (p = 0.153). CONCLUSION: Distant metastasis was the major failure pattern for CASTLE after surgery and IMRT. For patients with no lateral neck node metastasis, the omission of irradiation for lateral neck nodal regions seems to be safe and feasible.


Assuntos
Carcinoma , Radioterapia de Intensidade Modulada , Humanos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Carcinoma/patologia , Planejamento da Radioterapia Assistida por Computador/métodos , Metástase Linfática/radioterapia
11.
Sensors (Basel) ; 22(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36146131

RESUMO

This study aims to reveal the buckling behavior of filament-wound composite cylindrical shells subjected to external pressure. The boundary conditions of the cylindrical shells were one end fixed and the other free. The carbon fiber stacking sequences were [±90]2/([±20]/[±90]/[±40]/[±90]/[±60]/[±90])2/[±90]. Finite element software ANSYS 16.2 was used for the numerical simulation to predict the critical buckling pressure and buckling behavior of composite cylindrical shell. External hydrostatic pressure tests were conducted, where the buckling behavior and strain response were observed. Numerical simulation accurately predicted the critical buckling pressure of carbon fiber/epoxy filament composite cylindrical shells under external pressure with 3.5% deviation from the experimental results. The buckling modes simulated by the finite element method agreed well with the deformed shape observed in the experiment, which was characterized by the uniform distribution of the three hoop waves. Comparing the axial compressive strain and hoop compressive strain of the composite shell, it was found that the circumferential stiffness of the shell was weaker than the axial stiffness. In addition, a comparative study of the strains of the fixed-end and free-end metal control sleeves was carried out. The results show that the boundary conditions have a significant influence on the strain response of control sleeves.

12.
Small ; 15(33): e1900501, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31282114

RESUMO

Photothermal therapy (PTT) usually requires hyperthermia >50 °C for effective tumor ablation, which inevitably induces heating damage to the surrounding normal tissues/organs. Moreover, low tumor retention and high liver accumulation are the two main obstacles that significantly limit the efficacy and safety of many nanomedicines. To solve these problems, a smart albumin-based tumor microenvironment-responsive nanoagent is designed via the self-assembly of human serum albumin (HSA), dc-IR825 (a cyanine dye and a photothermal agent), and gambogic acid (GA, a heat shock protein 90 (HSP90) inhibitor and an anticancer agent) to realize molecular targeting-mediated mild-temperature PTT. The formed HSA/dc-IR825/GA nanoparticles (NPs) can escape from mitochondria to the cytosol through mitochondrial disruption under near-infrared (NIR) laser irradiation. Moreover, the GA molecules block the hyperthermia-induced overexpression of HSP90, achieving the reduced thermoresistance of tumor cells and effective PTT at a mild temperature (<45 °C). Furthermore, HSA/dc-IR825/GA NPs show pH-responsive charge reversal, effective tumor accumulation, and negligible liver deposition, ultimately facilitating synergistic mild-temperature PTT and chemotherapy. Taken together, the NIR-activated NPs allow the release of molecular drugs more precisely, ablate tumors more effectively, and inhibit cancer metastasis more persistently, which will advance the development of novel mild-temperature PTT-based combination strategies.


Assuntos
Albuminas/administração & dosagem , Hipertermia Induzida/métodos , Terapia de Alvo Molecular , Fototerapia/métodos , Células A549 , Albuminas/farmacocinética , Animais , Terapia Combinada , Endocitose , Humanos , Camundongos , Nanopartículas/uso terapêutico , Neoplasias/terapia , Temperatura , Distribuição Tecidual
13.
J Am Chem Soc ; 140(11): 4062-4070, 2018 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-29406728

RESUMO

Research on nanomedicines has rapidly progressed in the past few years. However, due to the limited size of nuclear pores (9-12 nm), the nuclear membrane remains a difficult barrier to many nucleus-targeting agents. Here, we report the development of a general platform to effectively deliver chemical compounds such as drug molecules or nanomaterials into cell nuclei. This platform consists of a polyamine-containing polyhedral oligomeric silsesquioxane (POSS) unit, a hydrophilic polyethylene glycol (PEG) chain, and the photosensitizer rose bengal (RB), which can self-assemble into nanoparticles (denoted as PPR NPs). Confocal fluorescence imaging showed that PPR NPs mainly located in lysosomes after cellular internalization. After mild light irradiation, however, PPR NPs effectively disrupted lysosomal structures by singlet oxygen (1O2) oxidation and substantially accumulated on nuclear membranes, which enabled further disruption of the membrane integrity and promoted their final nuclear entry. Next, we selected two chemotherapeutic agents (10-hydroxycamptothecine and docetaxel) and a fluorescent dye (DiD) as payloads of PPR NPs and successfully demonstrated that this nanocarrier could efficiently deliver them into cell nuclei in a light-controlled manner. In addition to molecular compounds, we have also demonstrated that PPR NPs could facilitate the nuclear entry of nanomaterials, including Prussian blue NPs as well as gold nanorods. Compared to traditional strategies for nuclear delivery, this highly controllable nanoplatform avoids complicated modification of nucleus-targeting ligands and is generally applicable to both molecular compounds and nanomaterials.


Assuntos
Núcleo Celular/química , Sistemas de Liberação de Medicamentos , Luz , Nanopartículas/química , Camptotecina/análogos & derivados , Camptotecina/química , Camptotecina/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Docetaxel , Corantes Fluorescentes/química , Humanos , Compostos de Organossilício/química , Tamanho da Partícula , Poliaminas/química , Polietilenoglicóis/química , Rosa Bengala/química , Taxoides/química , Taxoides/farmacologia
14.
Yi Chuan ; 39(2): 143-155, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28242601

RESUMO

We carried out a study of regeneration capacities of embryonic callus from maize immature embryo culture with 144 different inbred lines of natural groups from different countries, and found that the regeneration capacity was affected by three factors: environment, genotype and the interaction between the environment and genotype. We found that green embryonic callus rate (GCR), embryonic callus differentiating rate (CDR) and the plantlet number of embryonic callus regeneration (CPN) have significant positive correlations with each other, and they all have significant negative correlations with embryonic callus browning rate (CBR). Moreover, embryonic callus cloning index for the first subculture (CCI1) and embryonic callus cloning index for the second subculture (CCI2) have a significant positive correlation with each other, and CCI2 is positively correlated with green GCR, and is negatively correlated with CBR. Embryonic callus rooting rate (CRR) is positively correlated with GCR, CDR and CPN to some degree. Furthermore, we calculated Broad-Sense Heritability of each trait, and uncovered that the heritability index of CCI1, CCI2 and CRR was lower, and the heritability index of others was higher. In addition, by using the Ward method for two-way cluster analysis, we found eleven inbred lines with high regenerating abilities, and the rooting situation of regenerating plantlet was excellent by rooting culture, which could be used as the elite inbred lines of the maize transgenic receptor.


Assuntos
Regeneração/fisiologia , Sementes/crescimento & desenvolvimento , Zea mays/genética , Análise por Conglomerados , Técnicas de Cultura de Tecidos , Zea mays/embriologia , Zea mays/fisiologia
15.
Zhongguo Zhong Yao Za Zhi ; 42(1): 182-186, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-28945046

RESUMO

To analyze the medication features and the regularity of prescriptions of traditional Chinese medicine in treating patients with Qi-deficiency and blood-stasis syndrome of chronic heart failure based on modern literature. In this article, CNKI Chinese academic journal database, Wanfang Chinese academic journal database and VIP Chinese periodical database were all searched from January 2000 to December 2015 for the relevant literature on traditional Chinese medicine treatment for Qi-deficiency and blood-stasis syndrome of chronic heart failure. Then a normalized database was established for further data mining and analysis. Subsequently, the medication features and the regularity of prescriptions were mined by using traditional Chinese medicine inheritance support system(V2.5), association rules, improved mutual information algorithm, complex system entropy clustering and other mining methods. Finally, a total of 171 articles were included, involving 171 prescriptions, 140 kinds of herbs, with a total frequency of 1 772 for the herbs. As a result, 19 core prescriptions and 7 new prescriptions were mined. The most frequently used herbs included Huangqi(Astragali Radix), Danshen(Salviae Miltiorrhizae Radix et Rhizoma), Fuling(Poria), Renshen(Ginseng Radix et Rhizoma), Tinglizi(Semen Lepidii), Baizhu(Atractylodis Macrocephalae Rhizoma), and Guizhi(Cinnamomum Ramulus). The core prescriptions were composed of Huangqi(Astragali Radix), Danshen(Salviae Miltiorrhizae Radix et Rhizoma) and Fuling(Poria), etc. The high frequent herbs and core prescriptions not only highlight the medication features of Qi-invigorating and blood-circulating therapy, but also reflect the regularity of prescriptions of blood-circulating, Yang-warming, and urination-promoting therapy based on syndrome differentiation. Moreover, the mining of the new prescriptions provide new reference and inspiration for clinical treatment of various accompanying symptoms of chronic heart failure. In conclusion, this article provides new reference for traditional Chinese medicine in the treatment of chronic heart failure.


Assuntos
Mineração de Dados , Medicamentos de Ervas Chinesas/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Qi , Humanos , Medicina Tradicional Chinesa
16.
Ann Vasc Surg ; 30: 227-35, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541969

RESUMO

BACKGROUND: The diagnosis of isolated visceral artery dissection (IVAD) has become more common with the increasing use of computed tomography angiography (CTA). We examined the presentation, treatment, and outcomes of patients with IVAD treated at our institution. METHODS: The records of 72 patients treated for IVAD between January 2010 and August 2014 were analyzed retrospectively. All were treated with antiplatelet or anticoagulant drugs after admission and were continued on oral aspirin for at least 1 year. Four asymptomatic and 52 symptomatic patients were managed conservatively with blood pressure control, bowel rest, fluid supplementation, and nutritional support. Two patients underwent open surgery because of hematochezia and 16 underwent endovascular bare-metal stenting. RESULTS: Symptoms gradually resolved in those treated conservatively, and favorable arterial wall remodeling was observed in 16 patients. Twenty-one stents were implanted in 16 patients with superior mesenteric artery dissection; 3 patients required overlapping stents. During follow-up (range, 3-53 months), all patients were symptom-free, and there were no recurrences. Follow-up CTA of patients who underwent endovascular stenting demonstrated satisfactory stent and true lumen patency. CONCLUSIONS: IVAD is not uncommon. It occurs most frequently between the ages of 46 and 60 years and affects more men than women. A favorable outcome can be achieved in most of the patients with conservative management. Ischemic bowel necrosis is rare but requires open surgery. Endovascular bare-metal stenting is recommended when there is persistent abdominal pain, progression of the lesion, apparent stenosis of a true lumen compressed by a false lumen, or dilation of false lumen at a high risk of rupture.


Assuntos
Dissecção Aórtica/diagnóstico , Dissecção Aórtica/cirurgia , Procedimentos Endovasculares , Vísceras/irrigação sanguínea , Adulto , Idoso , Dissecção Aórtica/mortalidade , Anticoagulantes/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Retrospectivos , Stents , Resultado do Tratamento
17.
Anal Biochem ; 487: 8-16, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25957123

RESUMO

To clearly discriminate the results of simultaneous screening and quantification of up to 40 different targets-DNA sequences, long probes from 100 to 500 nt, rather than smaller or similar-sized synthetic ones, were adopted for multiplex ligation-dependent probe amplification (MLPA). To prepare the long probes, asymmetric polymerase chain reaction (PCR) was employed to introduce non-complementary stuffers in between the two parts of the MLPA probe with specially designed primers, then restriction enzymes were selected to digest the double-stranded DNAs, and finally polyacrylamide gel electrophoresis was used to purify the single-stranded DNAs (i.e., the long probes). By using this approach, 12 long probes were prepared and used to identify genetically modified (GM) maize. Our experimental results show that the prepared long probes were in full accordance with the designed ones and could be assembled in 4-, 7-, and 10-plex MLPA analysis without losing result specificity and accuracy, showing they were as effective and reliable in MLPA analysis as those prepared with M13-derived vectors. This novel asymmetric PCR-based approach does not need expensive equipment, special reagents, or complicated operations when compared with previous methods. Therefore, our new approach could make MLPA analysis more independent, efficient, and economical.


Assuntos
DNA de Cadeia Simples/genética , Reação em Cadeia da Polimerase Multiplex , Eletroforese em Gel de Poliacrilamida
18.
J Sci Food Agric ; 95(7): 1544-53, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25087732

RESUMO

BACKGROUND: The immune system is important in preventing and controlling various infectious diseases. Immunoactive peptides derived from food proteins could exert immunomodulatory activity without side effects. Paphia undulata with high-protein is suitable for the production of immunoactive peptides. The objective of this study was to optimize the hydrolysis parameters to maximize the immune activity of hydrolysates from Paphia undulata. RESULTS: Hydrolysis parameters, including temperature, time and the ratio of alkaline protease to Paphia undulata meat (E/S), were optimized by response surface methodology with a central composite design. The optimum conditions were obtained as follows: temperature, 51 °C; time, 3.14 h; E/S, 4,321 U g(-1) (Paphia undulata meat). Furthermore, hydrolysates obtained under the optimum conditions were fractionated by ultrafiltration and gel filtration on a Sephadex G-25 column. After two-step isolation, the isolated fractions (P2 and P3) including the peptides Pro-His-Thr-Cys, Val-Gly-Try-Thr, Glu-Phe, Leu-Phe, and Glu-Gly-Ala-Lys, Trp-Ile or Trp-Leu, respectively, could significantly enhance lymphocyte proliferation ability. CONCLUSION: These results showed that response surface methodology and two-step separation were efficient for recovery of low-molecular-weight peptides with high spleen lymphocyte proliferation activity, and the isolated fractions of Paphia undulata hydrolysates are potential ingredients for development of functional foods.


Assuntos
Bivalves/química , Proteínas Alimentares/farmacologia , Imunidade/efeitos dos fármacos , Linfócitos/metabolismo , Fragmentos de Peptídeos/farmacologia , Hidrolisados de Proteína/farmacologia , Alimentos Marinhos , Sequência de Aminoácidos , Animais , Proteínas Alimentares/metabolismo , Alimento Funcional , Hidrólise , Masculino , Camundongos , Fragmentos de Peptídeos/metabolismo , Hidrolisados de Proteína/metabolismo
19.
ScientificWorldJournal ; 2014: 163949, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25276844

RESUMO

Metamodels have been widely used in engineering design to facilitate analysis and optimization of complex systems that involve computationally expensive simulation programs. The accuracy of metamodels is directly related to the experimental designs used. Optimal Latin hypercube designs are frequently used and have been shown to have good space-filling and projective properties. However, the high cost in constructing them limits their use. In this paper, a methodology for creating novel Latin hypercube designs via translational propagation and successive local enumeration algorithm (TPSLE) is developed without using formal optimization. TPSLE algorithm is based on the inspiration that a near optimal Latin Hypercube design can be constructed by a simple initial block with a few points generated by algorithm SLE as a building block. In fact, TPSLE algorithm offers a balanced trade-off between the efficiency and sampling performance. The proposed algorithm is compared to two existing algorithms and is found to be much more efficient in terms of the computation time and has acceptable space-filling and projective properties.


Assuntos
Algoritmos , Simulação por Computador , Software , Modelos Teóricos , Reprodutibilidade dos Testes , Design de Software
20.
ScientificWorldJournal ; 2014: 192862, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25133206

RESUMO

Metamodels have been widely used in engineering design to facilitate analysis and optimization of complex systems that involve computationally expensive simulation programs. The accuracy of metamodels is strongly affected by the sampling methods. In this paper, a new sequential optimization sampling method is proposed. Based on the new sampling method, metamodels can be constructed repeatedly through the addition of sampling points, namely, extrema points of metamodels and minimum points of density function. Afterwards, the more accurate metamodels would be constructed by the procedure above. The validity and effectiveness of proposed sampling method are examined by studying typical numerical examples.


Assuntos
Modelos Teóricos , Algoritmos
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