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1.
J Control Release ; 316: 317-330, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31733293

RESUMO

Although microRNAs (miRNAs) function as the important tumor gene regulators, they still confront with many challenges in systemic delivery. Here, the amphiphilic gemcitabine-oleic acid prodrugs (GOA) binding miRNAs with hydrogen bond are assembled into nanoparticles (GOA/miR NPs) through hydrophobic interaction via denaturation-annealing processes and nano-precipitation technique. The non-cationic GOA/miR NPs with an average size of ~150 nm and a zeta potential of ~ - 15 mV exhibit a stable encapsulation of miRNAs with non-sequence selectivity. Either miR-122 or miR-34a encapsulated in the GOA/miR NPs is efficiently delivered into HepG2 cells and significantly downregulate the expression levels of target gene after lysosome escape and pH-responsive disassembly. Moreover, in vivo experiments demonstrate that the GOA/miR-122 NPs exhibit higher tumor accumulation. Compared to GOA micelles, GOA/miR-122 NPs displayed stronger tumor inhibition (73% regression) after intravenous injection in nude mice xenografted with HCC, along with rapid clearance in normal liver tissues. Furthermore, there is no significant influence on biochemical indicators and immune factors during the systematic administration of GOA/miR-122 NPs. The non-cationic GOA/miR NPs engineered by hydrogen bond interaction and hydrophobic forces show the enhanced synergistic antitumor efficacy and good biosafety, which will provide a potential nanomedcine for HCC treatment.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1402-1408, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607290

RESUMO

OBJECTIVE: To investigate the mechanism of rapamycin-induced apoptosis of chronic myelogenous leukemia cells. METHODS: The chronic granulocytic leukemia K562 cells were divided into 3 groups: A, B and C group were treated with rapamycin of 10, 15 and 20 nmol/L, repectively for 24 h, while the K562 cells in control group were not treated with rapamycin. The effect of rapamycin on the proliferation of K562 cells was detected by MTT, and the effect of rapamycin on the apoptosis of K562 cells was detected by AnnexinV-FITC/PI double staining. The expression level of EZH2/Hedgehog signaling pathway genes in K562 cells was detected by RT-PCR, and Western blot was used to detect the levels of apoptotic protein and the related signaling pathway proteins in K562 cells. RESULTS: The MTT assay showed that the different concentration of rapamycin had obvious inhibitory effects on the cells, and the survival rate of cells in group C was 37.6%±3.4%, which was significantly lower than that of the other groups (P<0.05). The apoptosis rate of cells in group C was 93.1%±8.1%, which was significantly higher than that of the other groups (P<0.05). By Western blot, it was found that the relative expression levels of Caspase-3 and BAX protein in group C were 0.36 ± 0.04 and 0.39±0.06, respectively, which were significantly higher than those in other groups (P<0.05), and the level of BCL-2 protein was 0.17±0.03, which was significantly lower than that of other groups (P<0.05). By RT-PCR, it was found that the mRNA levels of EZH2 and Hedgehog genes in A, B and C groups were significantly lower than those in the control group (P<0.05), but mRNA level of Ptch1 gene was significantly higher than that of the control (P<0.05). By Western blot, it was found that the expression levels of EZH2 and Hedgehog protein in A, B and C groups were significantly lower than that in the control group (P<0.05), but the level of Ptch1 protein was higher than that of the control (P<0.05). The relative levels of EZH2 and Hedgehog protein in group C were 0.21 ±0.03 and 0.16±0.05 respectively, which were significantly lower than those in other groups (P<0.05), and Ptch1 protein level were 0.46 ±0.06, significantly higher than that of other groups (P<0.05). CONCLUSION: Rapamycin can inhibit the protein expression of EZH2 in leukemic cells, thus interfere with the activation of Hedgehog signaling pathway, promote the expression of apoptotic protein, reduce the level of anti apoptotic protein, and eventually induce apoptosis of leukemia cells.


Assuntos
Transdução de Sinais/efeitos dos fármacos , Apoptose , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste , Proteínas Hedgehog , Humanos , Células K562 , Sirolimo
3.
Nat Commun ; 10(1): 4894, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653832

RESUMO

Cyber-physical systems embed software into the physical world. They appear in a wide range of applications such as smart grids, robotics, and intelligent manufacturing. Cyber-physical systems have proved resistant to modeling due to their intrinsic complexity arising from the combination of physical and cyber components and the interaction between them. This study proposes a general framework for discovering cyber-physical systems directly from data. The framework involves the identification of physical systems as well as the inference of transition logics. It has been applied successfully to a number of real-world examples. The novel framework seeks to understand the underlying mechanism of cyber-physical systems as well as make predictions concerning their state trajectories based on the discovered models. Such information has been proven essential for the assessment of the performance of cyber-physical systems; it can potentially help debug in the implementation procedure and guide the redesign to achieve the required performance.

4.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2742-2747, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31359685

RESUMO

The processing of Mongolian medicine,which is called " mort harl" in Mongolian language,refers to a traditional processing technology to " tame" some toxic,aggressive,ineffective or inconvenient Mongolian medicines,so as to make it " compliant" to clinical needs. It is the summary of long-term experience in drug preparation by Mongolian medicine experts,one of the bridges for the dialectical unity of Mongolian medicine,the essential content in evaluation of the clinical efficacy of Mongolian medicine and the study of Mongolian medicine modernization,and also the important soft power carrier of " intangible cultural heritage" and " grassland culture" in Inner Mongolia autonomous region. In this study,the processing history,purpose,crafts,mechanism,processing standards and quality standards of Mongolian medicine were explained,and some suggestions were proposed for the problems of the Mongolian medicine processing and development: focus on the basic theory of Mongolian medicine and the clinical experience of Mongolian medicine in the development of traditional Mongolian medicine processing; strengthen the literature research on the processing method of Mongolian medicine; establish comprehensive and systematic Mongolian medicine concocts standards and quality standards; enhance the research and development of special processing equipment and process quality control instruments for Mongolian medicine; and strengthen the training of professional technicians,the protection of copyright in Mongolian medicine processing,and scientific research on Mongolian medicine processing. In the inheritance of the tradition,the latest achievements of modern scientific development can be also absorbed to provide reference for the further development of traditional Mongolian medicine processing technology.


Assuntos
Medicina Tradicional da Mongólia , China , Controle de Qualidade , Padrões de Referência
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(6): 558-561, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31208509

RESUMO

OBJECTIVE: To study the clinical effect and safety of different maintenance doses of caffeine citrate in the treatment of apnea in very low birth weight preterm infants. METHODS: A total of 78 very low birth weight preterm infants with primary apnea were enrolled who were admitted from January 2016 to January 2018. They were randomly divided into high-dose caffeine group with 38 children and low-dose caffeine group with 40 children. Both groups received a loading dose of 20 mg/kg caffeine citrate, and 24 hours later, the children in the high-dose caffeine group were given a maintenance dose of 10 mg/kg, and those in the low-dose caffeine group were given a maintenance dose of 5 mg/kg. The two groups were compared in terms of response rate and incidence rate of adverse events. RESULTS: The high-dose caffeine group had a significantly higher response rate than the low-dose caffeine group (71% vs 48%; P<0.05). Compared with the low-dose caffeine group, the high-dose caffeine group had significantly shorter duration of apnea and time of caffeine treatment (P<0.05). There were no significant differences between the two groups in length of hospital stay and incidence rates of tachycardia, feeding intolerance, bronchopulmonary dysplasia, necrotizing enterocolitis, and intracranial hemorrhage (P>0.05). There was no significant difference in the mortality rate between the two groups (P>0.05). CONCLUSIONS: Higher maintenance dose of caffeine citrate has a better clinical effect than lower maintenance dose of caffeine citrate in the treatment of apnea in very low birth weight preterm infants, without increasing the incidence rates of adverse drug reactions and serious complications in preterm infants.


Assuntos
Apneia , Cafeína/uso terapêutico , Citratos/uso terapêutico , Apneia/tratamento farmacológico , Criança , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Estudos Prospectivos
6.
Nat Commun ; 10(1): 2702, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221991

RESUMO

Most cationic vectors are difficult to avoid the fate of small interfering RNA (siRNA) degradation following the endosome-lysosome pathway during siRNA transfection. In this study, the endoplasmic reticulum (ER) membrane isolated from cancer cells was used to fabricate an integrative hybrid nanoplexes (EhCv/siRNA NPs) for improving siRNA transfection. Compared to the undecorated Cv/siEGFR NPs, the ER membrane-decorated EhCv/siRNA NPs exhibits a significantly higher gene silencing effect of siRNA in vitro and a better antitumor activity in nude mice bearing MCF-7 human breast tumor in vivo. Further mechanistic studies demonstrate that functional proteins on the ER membrane plays important roles on improving cellular uptake and altering intracellular trafficking pathway of siRNA. It is worth to believe that the ER membrane decoration on nanoplexes can effectively transport siRNA through the endosome-Golgi-ER pathway to evade lysosomal degradation and enhance the silencing effects of siRNA.


Assuntos
Portadores de Fármacos/química , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Transfecção/métodos , Animais , Linhagem Celular Tumoral , Membrana Celular , Portadores de Fármacos/efeitos adversos , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Receptores ErbB/genética , Feminino , Terapia Genética/métodos , Complexo de Golgi/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Nanopartículas/química , Neoplasias/genética , Neoplasias/terapia , RNA Interferente Pequeno/efeitos adversos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Asian J Androl ; 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31134916

RESUMO

Many studies have shown that microRNAs (miRNAs) play vital roles during the spermatogenesis. However, little is known about the altered miRNA profiles of testicular tissues in nonobstructive azoospermia (NOA). Using microarray technology, the miRNA expression profiles of testicular biopsies from patients with NOA and of normal testicular tissues were determined. Bioinformatics analyses were conducted to predict the enriched biological processes and functions of identified miRNAs. The microarray data were validated by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), the results of which were then validated with a larger sample size. Correlations between the miRNA expression levels and clinical characteristics were analyzed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic ability of miRNAs for azoospermia. Hierarchical clustering showed that 129 miRNAs were significantly differentially expressed between the NOA and control groups. Bioinformatics analysis indicated that the differentially expressed miRNAs were involved in spermatogenesis, cell cycle, and mitotic prometaphase. In the subsequent qRT-PCR assays, the selected miRNA expression levels were consistent with the microarray results, and similar validated results were obtained with a larger sample size. Some clinical characteristics were significantly associated with the expression of certain miRNAs. In particular, we identified a combination of two miRNAs (miR-10b-3p and miR-34b-5p) that could serve as a predictive biomarker of azoospermia. This study provides altered miRNA profiles of testicular biopsies from NOA patients and examines the roles of miRNAs in spermatogenesis. These profiles may be useful for predicting and diagnosing the presence of testicular sperm in individuals with azoospermia.

8.
Bioorg Med Chem ; 27(12): 2598-2608, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30992204

RESUMO

Water-soluble porphyrins are considered promising drug candidates for photodynamic therapy (PDT). This study investigated the PDT activity of a new water-soluble, anionic porphyrin (1-Zn), which possesses four negative charges. The photodynamic anticancer activity of 1-Zn was investigated by the MTT assay, with mTHPC as a positive control. The cellular distribution was determined by fluorescence microscopy. Holographic and phase contrast images were recorded after 1-Zn treatment with a HoloMonitor™ M3 instrument. The inhibition of A549 cell growth achieved by inducing apoptosis was investigated by flow cytometry and fluorescence microscopy. DNA damage was investigated by the comet assay. The expression of apoptosis-related proteins was also measured by western blot assays. 1-Zn had better phototoxicity against A549 cells than HeLa and HepG2 cancer cells. Interestingly, 1-Zn was clearly located almost entirely in the cell cytoplasmic region/organelles. The late apoptotic population was less than 1.0% at baseline in the untreated and only light-treated cells and increased to 40.5% after 1-Zn treatment and irradiation (P < 0.05). 1-Zn triggered significant ROS generation after irradiation, causing ΔΨm disruption (P < 0.01) and DNA damage. 1-Zn induced A549 cell apoptosis via the mitochondrial apoptosis pathway. In addition, 1-Zn bound in the groove of DNA via an outside binding mode by pi-pi stacking and hydrogen bonding. 1-Zn exhibits good photonuclease activity and might serve as a potential photosensitizer (PS) for lung cancer cells.

9.
Respiration ; 97(5): 436-443, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30904909

RESUMO

BACKGROUND: Optimal management of persistent air leaks (PALs) in patients with secondary spontaneous pneumothorax (SSP) remains controversial. OBJECTIVE: To evaluate the efficacy and safety of endobronchial autologous blood plus thrombin patch (ABP) and bronchial occlusion using silicone spigots (BOS) in patients with SSP accompanied by alveolar-pleural fistula (APF) and PALs. METHODS: This prospective multicentre randomized controlled trial compared chest tube-attached water-seal drainage (CTD), ABP, and BOS that were performed between February 2015 and June 2017 in one of six tertiary care hospitals in China. Patients diagnosed with APF experiencing PALs (despite 7 days of CTD) and inoperable patients were included. Outcome measures included success rate of pneumothorax resolution at the end of the observation period (further 14 days), duration of air leak stop, lung expansion, hospital stay, and complications. RESULTS: In total, 150 subjects were analysed in three groups (CTD, ABP, BOS) of 50 each. At 14 days, 60, 82, and 84% of CTD, ABP, and BOS subjects, respectively, experienced full resolution of pneumothorax (p = 0.008). All duration outcome measures were significantly better in the ABP and BOS groups than in the CTD group (p < 0.016 for all). The incidence of adverse events, including chest pain, cough, and fever, was not significantly different. All subjects in the ABP and BOS groups experienced temporary haemoptysis. Spigot displacement occurred in 8% of BOS subjects. CONCLUSION: ABP and BOS resulted in clinically meaningful outcomes, including higher success rate, duration of air leak stop, lung expansion, and hospital stay, with an acceptable safety profile.

10.
Lasers Med Sci ; 34(7): 1353-1363, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30710171

RESUMO

Corrole is a kind of new and promising photosensitizer (PS) in cancer photodynamic therapy (PDT). However, the protein molecular mechanism of PDT activity for corrole under light irradiation is still not clear. In this paper, water-soluble cationic sulfonated corrole (1) and its metal complexes (1-Fe, 1-Mn, and 1-Cu) were prepared, and the photodynamic anti-cancer activity against various tumor cells was investigated by MTT assay. The potential molecular mechanism of PDT activity was elucidated by fluorescence microscope, flow cytometry, molecular docking, and western blotting analysis. Besides, the potential PDT anti-tumor effect of 1 in vivo was assessed in human tumor xenografts in mice. Quantitative analysis revealed that 1's phototoxicity triggered a significant generation of reactive oxygen species, causing disruption of mitochondrial membrane potential. The results of western blotting (WB) assay shown in 1's phototoxicity could induce cell apoptosis via ROS-mediated mitochondrial caspase apoptosis pathway, in which SIRT1 protein degradation played a key role. PTD activity in vivo shown in 1 could significantly reduce the growth of A549 xenografted tumor, without obvious loss of mice body weight. We clearly found that cationic sulfonated corrole is a potential candidate of PS in vitro and in vivo. The phototoxicity of 1 could induce A549 cell apoptosis by inducing ROS production increase, further to activate the mitochondrial apoptosis pathway. We concluded that SIRT1 protein is a more appropriate target in this progress.


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Fotoquimioterapia , Porfirinas/uso terapêutico , Ácidos Sulfônicos/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspases/metabolismo , Cátions , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Int J Pharm ; 559: 48-57, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30677483

RESUMO

Gemcitabine (Gem) as an anti-cancer agent has been limited by its short circulation time and rapid metabolism that reflects in low tumor uptake and low therapeutic efficiency. To improve its anti-tumor activity, a novel FAPα enzyme-activated prodrug of Z-GP-Gem modified at 4-amino group of Gem was developed, which could effectively release parent Gem based on the specific cleavage via FAPα enzyme-activation in tumor microenvironment. Compared to Gem, the Z-GP-Gem prodrug exhibited significantly enhanced inhibition of both tumor growth and pulmonary metastasis in BALB/c mice bearing orthotopic breast 4T1 tumors. The Z-GP-Gem prodrug has a prolonged circulation time and a high tumor uptake based on the modification of Z-GP dipeptide at 4-amino group of Gem. These eventually caused a marked improvement in the systemic toxicity and the tumor growth inhibition in 4T1 cells. More interestingly, the unexpected depletion of tumor-associated fibroblast (TAF) was observed during the treatment of Z-GP-Gem prodrug in animal model. Therefore, these findings demonstrated that the FAPα-activated prodrug Z-GP-Gem would be a desirable approach for tumor therapy by intravenous administration.


Assuntos
Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Gelatinases/metabolismo , Proteínas de Membrana/metabolismo , Pró-Fármacos/farmacologia , Serina Endopeptidases/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/farmacologia , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica/patologia , Células PC-3 , Ratos Sprague-Dawley , Microambiente Tumoral/efeitos dos fármacos
12.
Asian J Androl ; 21(5): 501-507, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30688213

RESUMO

Previous studies suggest that air pollution has a negative effect on semen quality. However, most studies are cross-sectional and the results are controversial. This study investigated the associations between air pollutants (PM2.5, PM10, SO2, NO2, CO, and O3) and semen quality among sperm donation candidates, especially when the air pollution was artificially controlled in Beijing, China. We analyzed 8945 semen samples in the human sperm bank of Peking University Third Hospital (Beijing, China) from October 2015 to May 2018. Air pollution data during the entire period (0-90 days prior) and key stages (0-9, 10-14, and 70-90 days prior) of sperm development were collected from the China National Environmental Monitoring Centre. The association between air pollutants and semen parameters (sperm concentration and progressive motility) was analyzed by a mixed model adjusted for age, abstinence duration, month, and average ambient temperature. Only O3during key stages of 0-9 days and 10-14 days and the entire period was negatively associated with sperm concentration between 2015 and 2018 (P < 0.01). During the period of air pollution control from November 2017 to January 2018, except for the increase in O3concentration, other five pollutants' concentrations decreased compared to those in previous years. In this period, the sperm concentration decreased (P < 0.001). During the pollution-control period, O3exposure 10-14 days prior was negatively associated with sperm concentration (95% CI: -0.399--0.111; P < 0.001). No significant association was found between the other five pollutants and semen quality during that period. Our study suggested that only O3exposure was harmful to semen quality. Therefore, O3should not be neglected during pollution control operation.

13.
Eur J Med Chem ; 163: 779-786, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30579120

RESUMO

The development of novel, efficient and nontoxic photosensitizers (PSs) is a challenging task for photodynamic therapy (PDT). In our previous study, corrole had been demonstrated to be a promising PS in PDT for cancer cells. In this paper, a novel electron-deficient flat phosphorus tris(ethoxycarbonyl) corrole (1-P) was synthesized and characterized. In vitro photodynamic activities and toxicity of 1-P in HepG2 xenograft tumours was evaluated by standard assay. The results shown 1-P displayed a potential efficient and low-toxic PS, which suggesting this kind of corrole is a powerful and promising antitumor PS for PDT. In addition, the potential anti-tumour mechanism study of 1-P was also investigated by the apoptosis antibody array, immunohistochemical and western blotting assay (WB) experiments, we found that the PDT activity of 1-P can degrade SIRT1 (an important deacetylase), and activate the Fas signal pathway to inhibit the growth of liver cancer cells.


Assuntos
Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Fósforo/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/toxicidade , Porfirinas/farmacologia , Sirtuína 1/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor fas/metabolismo
14.
Nat Prod Res ; : 1-7, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518257

RESUMO

One new indole-type alkaloid, α-L-rhamnopyranosyl-(1→6)-ß-D- glucopyranosyl 6-methoxy-3-indolecarbonate (1), together with three known alkaloids (2-4), one aromatic acid (5) and five known saponins (6-10), was isolated from the roots of Clematis florida var. plena. Their structures were established by NMR spectroscopic analysis and acid hydrolysis. In in vivo anti-inflammatory activity, n-butanol extract was found to be potent against ear edema in mice, with inhibition rate of 48.7% at a dose of 800 mg/kg. Furthermore, compounds 8 and 9 obtained from the n-butanol extract exhibited significant anti-inflammatory activities with inhibition rates of 50.9% and 54.7% at a dose of 200 mg/kg.

15.
Dalton Trans ; 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30265262

RESUMO

Heterometallic Ln-Pt complexes, with the formula [Ln2Pt3(H2O)2(SAc)12] (Ln = Ho(1), Er(2); SAc = thioacetate), were synthesized. From natural bond orbital (NBO) and local orbital locator (LOL) analyses and X-ray absorption fine structure (XAFS) measurements, it was clear that the Ln-Pt interactions or electron polarization occurred. Butterfly-type hysteresis was observed for both 1 and 2. 1 and 2 underwent field-induced slow magnetic relaxation up to 4 K. These magnetic properties were induced by Ln-Pt electron polarization.

16.
Asian J Androl ; 20(5): 442-447, 2018 Sep-Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30004040

RESUMO

Stem cell therapy is a potentially promising option for erectile dysfunction; however, its risk of tumorigenicity is a clinical hurdle and the risk is positively related to the number of injected cells. Our previous study showed that nanotechnology improved adipose-derived stem cell (ADSC) therapy for erectile dysfunction of cavernous nerve injury (CNI) by attracting cells in the corpus cavernosum. These results indicated the possibility of using a reduced dosage of ADSCs for intracavernous injection. In this exploratory study, we used lower dosage (2 × 105 cells) of ADSCs for intracavernous injection (ICI) and the nanotechnology approach. Intracavernous pressure and mean arterial pressure were measured at day 28 to assess erectile function. The low-dose ADSC therapy group showed favorable treatment effects, and nanotechnology further improved these effects. In vivo imaging of ICI cells revealed that the fluorescein signals of NanoShuttle-bound ADSCs (NanoADSCs) were much stronger than those of ADSCs at days 0, 1, and 3. Both immunofluorescence and Western blot analysis showed a significant increase in smooth muscle, endothelium, and nerve tissue in the ADSC group compared to that in the CNI group; further improvement was achieved with assisted nanotechnology. These findings demonstrate that nanotechnology can be used to further improve the effect of small dosage of ADSCs to improve erectile function. Abundant NanoADSCs remain in the corpus cavernosum in vivo for at least 3 days. The mechanism of erectile function improvement may be related to the regeneration of the smooth muscle, endothelium, and nerve tissues.

17.
Nat Prod Res ; : 1-7, 2018 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-29569484

RESUMO

Two new phenylspirodrimanes, stachybotrin H (1) and stachybotrysin H (9) together with eleven known analogues (2-8, 10-13) were isolated from deep-sea derived Stachybotrys sp. MCCC 3A00409. Their structures were determined by extensive NMR data and mass spectroscopic analysis. Compounds 9-12 showed weak cytotoxicity against three human cancer cell lines K562, Hela and HL60 with IC50 in the range of 18.5-52.8 µM.

18.
Phys Rev E ; 96(2-1): 022411, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28950513

RESUMO

Coordination shall be deemed to the result of interindividual interaction among natural gregarious animal groups. However, revealing the underlying interaction rules and decision-making strategies governing highly coordinated motion in bird flocks is still a long-standing challenge. Based on analysis of high spatial-temporal resolution GPS data of three pigeon flocks, we extract the hidden interaction principle by using a newly emerging machine learning method, namely the sparse Bayesian learning. It is observed that the interaction probability has an inflection point at pairwise distance of 3-4 m closer than the average maximum interindividual distance, after which it decays strictly with rising pairwise metric distances. Significantly, the density of spatial neighbor distribution is strongly anisotropic, with an evident lack of interactions along individual velocity. Thus, it is found that in small-sized bird flocks, individuals reciprocally cooperate with a variational number of neighbors in metric space and tend to interact with closer time-varying neighbors, rather than interacting with a fixed number of topological ones. Finally, extensive numerical investigation is conducted to verify both the revealed interaction and decision-making principle during circular flights of pigeon flocks.


Assuntos
Comportamento Animal , Columbidae , Voo Animal , Modelos Biológicos , Comportamento Social , Comportamento Espacial , Animais , Teorema de Bayes , Simulação por Computador , Tomada de Decisões , Aprendizado de Máquina , Movimento (Física) , Probabilidade
19.
Sci Rep ; 7(1): 10452, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28874738

RESUMO

Collective circular motion is a common yet spectacular behavior of pigeon flocks. Efficient and robust inter-individual communication is required for flock coordination during this widely-spreaded movement pattern. When a flock hovers near the home loft, the rotational direction undergoes regular spontaneous variations. Based on intensive analyses of high spatial-temporal resolution GPS data, we quantified the intensity of velocity alignment among different individuals in terms of their velocity fluctuations. It is found that pigeon flocks employ an intermittent interaction (alignment) mechanism, where intra-group information transmission is not required at every instant. However, the union of the topologies of several consecutive interaction networks always keeps connected. This biological observation strongly suggests the presence of a jointly connected topology in pigeon flocks, which helps substantially reduce the communication and/or information processing requirements while retaining the agility and stability of the group. Finally, we conducted extensive investigation on the interaction mechanism as well as the spontaneous changes in rotational direction of pigeon flocks. These results shed some light onto the coordination mechanism exploration of bird flocks' collective motions.

20.
Dalton Trans ; 46(29): 9481-9490, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28702557

RESUMO

Corroles have been previously demonstrated to be a new and promising photosensitizer (PS) in photodynamic therapy (PDT) for cancer cells. This research reported the preparation of an electron-deficient flat gallium(iii) tris(ethoxycarbonyl)corrole (1-Ga). Its in vitro PDT activities towards different cancer cell lines were examined, and the best PDT activity was observed in A549 cell lines. 1-Ga could penetrate the cell membrane rapidly and exhibit remarkable photo-cytotoxicity. 1-Ga can induce A549 cell apoptosis via ROS-mediated mitochondrial pathways, in which p38 and sirt-1 proteins play a key role. A PTD test in vivo showed that 1-Ga can significantly reduce the growth of A549 xenografted tumor cells without an obvious loss of mice weight upon PDT treatment.

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