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1.
Nanoscale ; 13(44): 18773-18779, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34747962

RESUMO

Production of ethylene glycol from coal is a particularly interesting route as it is an economic alternative to the petrochemical-based route. In this process, effectively generating dimethyl oxalate (DMO) is a crucial step by CO oxidative coupling reaction under Pd-based catalysts. However, the aggregation of Pd species over the support is still an issue that relates to the deterioration of catalytic activity and stability. To this end, enhancing the metal-support interaction is urgently required. In this work, hierarchical Nb2O5 (H-Nb2O5) microspheres with abundant oxygen defects were synthesized to anchor the Pd species thus promoting the electron transfer between Pd species and Nb species associated with the generation of interfacial Pd-NbOx sites. Besides, the thinned electron density of Pd species resulting from the electron-withdrawing effect of Nb species is beneficial for activating the adsorbed CO molecules, leading to superior catalytic activity. The Pd/H-Nb2O5 catalyst exhibited 63.1% of CO conversion (theoretical maximum conversion: 64.3%) and 92.9% of DMO selectivity, with a DMO weight time yield of 1297.9 g kgcat.-1 h-1, and remained robust even after 50 h of time on stream evaluation. Current work provides a deep insight into the CO activation mechanism and helps improve the catalytic stability by boosting interfacial electron interaction via oxygen defects induction, and also sheds light on the design and synthesis of high-performance catalysts in other heterogeneous catalysis fields.

2.
Acta Pharmacol Sin ; 42(5): 824-831, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32901086

RESUMO

Clinical tracking of chimeric antigen receptor (CAR) T cells in vivo by positron emission tomography (PET) imaging is an area of intense interest. But the long-lived positron emitter-labeled CAR T cells stay in the liver and spleen for days or even weeks. Thus, the excessive absorbed effective dose becomes a major biosafety issue leading it difficult for clinical translation. In this study we used 68Ga, a commercially available short-lived positron emitter, to label CAR T cells for noninvasive cell tracking in vivo. CAR T cells could be tracked in vivo by 68Ga-PET imaging for at least 6 h. We showed a significant correlation between the distribution of 89Zr and 68Ga-labeled CAR T cells in the same tissues (lungs, liver, and spleen). The distribution and homing behavior of CAR T cells at the early period is highly correlated with the long-term fate of CAR T cells in vivo. And the effective absorbed dose of 68Ga-labeled CAR T cells is only one twenty-fourth of 89Zr-labeled CAR T cells, which was safe for clinical translation. We conclude the feasibility of 68Ga instead of 89Zr directly labeling CAR T cells for noninvasive tracking of the cells in vivo at an early stage based on PET imaging. This method provides a potential solution to the emerging need for safe and practical PET tracer for cell tracking clinically.


Assuntos
Rastreamento de Células/métodos , Compostos Radiofarmacêuticos/química , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/metabolismo , Animais , Linfoma de Burkitt/terapia , Linhagem Celular Tumoral , Estudos de Viabilidade , Radioisótopos de Gálio/química , Humanos , Imunoterapia Adotiva , Oxiquinolina/química , Oxiquinolina/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos/química , Compostos Radiofarmacêuticos/farmacocinética , Linfócitos T/química , Zircônio/química
3.
Dalton Trans ; 49(6): 1803-1810, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31989138

RESUMO

With the in situ-generated [Pb(MCP)4]2+ (HMCP+ = 1-methyl-4-(carboxyl)pyridinium) or [M(phen)3]2+ (M = Co, Fe and Ni; phen = 1,10-phenanthroline) complexes as structural directing agents and charge-balancing ions, we solvothermally synthesized and structurally characterized four new organic-inorganic hybrid iodoplumbates. Compound K2[Pb(MCP)4]Pb3I10 (1) represents the first K+ and [Pb(MCP)4]2+ co-templated hybrid haloplumbate, and exhibits a curve-like anionic layer of [Pb3I10]n4n-. Compounds [M(phen)3]Pb2I6·CH3CN (M = Co (2), Fe (3) and Ni (4)) have isostructural phases, and feature a one-dimensional (1D) [Pb2I6]n2n- anionic chain characteristic of pyramid-like [PbI5] units. The optical property studies show that compounds 1-4 exhibit semiconductor behaviors with the band gaps of 1.98-2.68 eV. In addition, the title compounds exhibited interesting photoelectrical responsive properties, with the photocurrent density in the order of 1 > 3 > 2 > 4. The thermal stabilities of the title compounds 1-4, as well as the theoretical band structure and density of states (DOS) of compounds 1 and 2 have also been studied.

4.
Huan Jing Ke Xue ; 40(5): 2249-2257, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087863

RESUMO

Yilong Lake, a shallow, plateau lake, is the ninth largest water body in the Yunnan Province, China. In order to figure out the characteristics of phytoplankton communities in different regions of this lake, the phytoplankton and environmental factors in the west region, east region, and in a submerged macrophytes restoration demonstration region were monthly investigated and analyzed from August 2013 to July 2014. The results showed that the habitats in different regions were spatially heterogeneous. Total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH4+-N), five-day biochemical oxygen demand (BOD5), transparency (SD), turbidity (Turb.), and electrical conductivity (EC) had no significant differences between the demonstration region and the west region, but these two regions showed significant differences in comparison with the east region (P<0.05). The largest phytoplankton density was Cyanophyta and the dominant species in the three regions were different. Mersmopedia tenuissima had the highest dominance in the west region; Cylindrospermopsis raciborskii and Pseudanabaena limntica were the most dominant taxa in the east region; while Merismopedia tenuissima and Anabaenopsis sp. were dominant in the O. uminata restoration demonstration region. PCoA compared the ß diversity of phytoplankton communities in the three different regions based on the entire year investigations. It was found that the community structures of the west region and O. uminata restoration demonstration region were similar (P>0.05), but they were significantly different from the community from the east region (P<0.01). Redundant analysis (RDA) showed that TN, TP, BOD5, and SD were the main environmental factors affecting the distribution of phytoplankton community in Yilong Lake. In addition, NH4+-N, EC, permanganate index, and pH also have a certain effect on the phytoplankton community.


Assuntos
Lagos , Fitoplâncton/classificação , Fitoplâncton/crescimento & desenvolvimento , Análise da Demanda Biológica de Oxigênio , China , Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Qualidade da Água
5.
Biomacromolecules ; 20(3): 1455-1463, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30764611

RESUMO

Nonconjugated red fluorescent polymers have been increasingly studied to improve the biocompatibility and penetration depth over conventional fluorescent materials. However, the accessibility of such polymers remains challenging due to the scarcity of nonconjugated fluorophores and lacking relevant mechanism of red-shifted fluorescence. Herein, we discovered that the combination of hydrogen bonding and π-π stacking interactions provides nonconjugated poly(amide-imide) with a large bathochromic shift (>100 nm) from blue-green fluorescence to red emission. The amphiphilic PEGylated poly(amide-imide) derived from in situ PEGylation self-assembled into nanovesicles in water, which isolated the aminosuccinimide fluorophore from the solvents and suppressed the hydrogen bonds formation between aminosuccinimide fluorophores and water. Therefore, the fluorescence of PEGylated poly(amide-imide) in water was soundly retained. Furthermore, the strong hydrogen bonding and hydrophobic interactions with water provided PEGylated poly(amide-imide) with a reversible thermoresponsiveness and presented a concentration-dependent behavior. Finally, accompanied by the excellent biostability and photostability, PEGylated poly(amide-imide) exhibited as a good candidate for cell imaging.


Assuntos
Amidas/química , Corantes Fluorescentes/química , Imidas/química , Polímeros/química , Fluorescência , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
6.
Data Brief ; 19: 1257-1265, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30229005

RESUMO

The characterization of products produced from hydrothermal liquefaction of algal biomass is helpful to better understand the effect of different kinds of raw materials on the properties of the product fractions. The data presented in this article are related to the research article entitled "Integration of hydrothermal liquefaction and supercritical water gasification for the improvement of energy recovery from algal biomass" (Duan et al., 2018) [1]. In this data article, the compositions of gaseous products produced from hydrothermal liquefaction of eight different algae feedstocks at 350 °C for 60 min were analyzed by gas chromatography. The molecular and elemental compositions of the crude bio-oils produced from hydrothermal liquefaction of eight different algae feedstocks at 350 °C for 60 min were analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry and organic elemental analyzer. The color of aqueous phases before and after they were subjected to supercritical water gasification was recorded by a high-resolution camera.

7.
Sci Total Environ ; 636: 953-962, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29729513

RESUMO

A comprehensive comparison of hydrothermal liquefaction (HTL) to the pyrolysis of duckweed was conducted to determine the yields and components of the crude bio-oils and their distillates. The upgrading behaviors of the distillates were thoroughly investigated with the use of used engine oil as a solvent. With all other variables fixed, HTL produced crude bio-oil with a lower H/C ratio (1.28 ±â€¯0.03) than pyrolysis did (1.45 ±â€¯0.04). However, its distillates had a higher H/C ratio (1.60 ±â€¯0.05) and total yield (66.1 ±â€¯2.0 wt%) than pyrolysis (1.46 ±â€¯0.04 and 47.2 ±â€¯1.4 wt%, respectively). Phenolics and nitrogenous heterocycles constituted relatively major proportions of the two crude bio-oils and most of their distillates. Obvious differences in molecular composition between the two crude bio-oils and their distillates were ascribed to the distinct impacts of HTL and pyrolysis and were affected by the distillate temperature. Co-hydrotreating with used engine oil (UEO) provided the upgraded bio-oils much higher H/C ratios (~1.78 ±â€¯0.05) and higher heating values (~45.5 ±â€¯1.4 MJ·kg-1), as well as much lower contents of N, O and S compared to their initial distillates. Aromatics and alkanes constituted a large proportion in most of upgraded bio-oils. N removal from the pyrolysis distillates was easier than from the HTL distillates. Distinct differences in yields and molecular compositions for the upgraded bio-oils were also attributed to the different influences associated with the two conversion routes.

8.
Biotechnol Biofuels ; 11: 83, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29619079

RESUMO

Background: In this study, a two-step processing method (hydrothermal liquefaction followed by catalytic upgrading) was used to produce upgraded bio-oil. A comprehensive screening analysis of algal species, including four microalgae and four macroalgae, was conducted to bridge the gap between previous accounts of microalgae and macroalgae hydrothermal liquefaction and the upgrading process of the resulting crude bio-oils. Results: Hydrothermal liquefaction using eight algal biomasses was performed at 350 °C for 1 h. The microalgae always produced a higher crude bio-oil yield than the macroalgae due to their high lipid content, among which Schizochytrium limacinum provided the maximum crude bio-oil yield of 54.42 wt%. For microalgae, higher amounts of N in the biomass resulted in higher amounts of N in the crude bio-oil; however, contrary results were observed for the macroalgae. The crude bio-oils generated from both the microalgae and macroalgae were characterized as having a high viscosity, total acid number, and heteroatom content, and they were influenced by the biochemical compositions of the feedstocks. Next, all eight-crude bio-oils were treated at 400 °C for 2 h with 10 wt% Ru/C using tetralin as the hydrogen donor. The hydrogen source was provided after tetralin was transformed to naphthalene. All the upgraded bio-oils had higher energy densities and significantly lower N, O, and S contents and viscosities than their corresponding crude bio-oils. However, the H/C molar ratio of the upgraded bio-oils decreased due to the absence of external hydrogen relative to the crude bio-oils. The S content of the upgraded bio-oil produced from upgrading the Schizochytrium limacinum crude bio-oil was even close to the 50 ppm requirement of China IV diesel. Conclusions: Microalgae are better feedstocks than macroalgae for liquid fuel production. Biochemical components have a significant impact on the yield and composition of crude bio-oil. Tetralin does not perform as well as external hydrogen for controlling coke formation. The S content of the upgraded bio-oil can be reduced to 76 ppm for the crude bio-oil produced from Schizochytrium limacinum. Upgraded bio-oils have similar properties to those of naphtha and jet fuel.

9.
Sci Total Environ ; 630: 243-253, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29477822

RESUMO

Supercritical water gasification (SCWG) of the microalga Chlorella pyrenoidosa was examined with a catalyst mixture of Ru/C and Rh/C in a mass ratio of 1:1. The influences of temperature (380-600°C), water density (0-0.197g/cm3), and catalyst loading (0-20wt%) on the yields and composition of the gaseous products and the gasification efficiency were examined. The temperature and water density significantly affected the SCWG of the microalgae. The hydrogen gasification efficiency was more dependent on the temperature, while the carbon gasification efficiency was more dependent on the water density. The gaseous products mainly consisted of CH4, H2, CO, and CO2, with smaller amounts of C2-C3 hydrocarbons. CH4 made up half of the mole fraction of the gaseous products under most reaction conditions. A synergistic effect between Ru/C and Rh/C existed during the SCWG of the microalgae, and this effect favored the production of CH4. The role of the catalyst mixture became indistinct at higher temperatures. Hydrogen atoms from the water were transferred to the gaseous products during the SCWG, leading to hydrogen gasification efficiencies that exceeded 100%. The main components of the bio-oil were aromatics and nitrogen-containing compounds, and the main aromatics consisted of azulene and anthracene. The nitrogen-containing compounds are potential poisons to the catalyst mixture.


Assuntos
Chlorella/fisiologia , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/metabolismo , Carbono , Catálise , Gases , Temperatura Alta , Hidrogênio , Esgotos , Temperatura
10.
World J Gastrointest Oncol ; 8(2): 165-72, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26909131

RESUMO

Pancreatic cancer (PC) is a major health problem. Conventional imaging modalities show limited accuracy for reliable assessment of the tumor. Recent researches suggest that molecular imaging techniques with tracers provide more biologically relevant information and are benefit for the diagnosis of the cancer. In addition, radiopharmaceuticals also play more important roles in treatment of the disease. This review summaries the advancement of the radiolabeled compounds in the theranostics of PC.

11.
Contrast Media Mol Imaging ; 9(5): 342-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24729577

RESUMO

Overexpression of the gastrin-releasing peptide receptor (GRPR) in prostate cancer provides a promising target for detection the disease. MATBBN is a new bombesin analog originating from the GRPR antagonists with a hydrophilic linker. In this study NOTA-conjugated MATBBN was labeled by the Al(18)F method and the potential of (18)F-Al-NOTA-MATBBN for prostate tumor PET imaging was also evaluated. NOTA-MATBBN was radiolabeled with (18) F using Al(18)F complexes. Partition coefficient, in vitro stability and GRPR binding affinity were also determined. PET studies were performed with (18)F-Al-NOTA-MATBBN in PC-3 tumor-bearing mice. (18)F-Al-NOTA-MATBBN can be produced within 30 min with a decay-corrected yield of 62.5 ± 2.1% and a radiochemical purity of >98%. The logP octanol-water value for the Al(18)F-labeled BBN analog was -2.40 ± 0.07 and the radiotracer was stable in phosphate-buffered saline and human serum for 2 h. The IC50 values of displacement for the (18)F-Al-NOTA-MATBBN with MATBBN was 126.9 ± 2.75 nm. The PC-3 tumors were clearly visible with high contrast after injection of the labeled peptide. At 60 min post-injection, the tumor uptakes for (18)F-Al-NOTA-MATBBN and (18)F-FDG were 4.59 ± 0.43 and 1.98 ± 0.35% injected dose/g, and tumor to muscle uptake radios for two tracers were 6.77 ± 1.10 and 1.78 ± 0.32, respectively. Dynamic PET revealed that (18) F-Al-NOTA-MATBBN was excreted mainly through the kidneys. GRPR-binding specificity was also demonstrated by reduced tumor uptake of (18)F-Al-NOTA-MATBBN after coinjection with excess unlabeled MATBBN peptide at 1 h post-injection. NOTA- MATBBN could be labeled rapidly with (18)F using one step method. (18)F-Al-NOTA-MATBBN may be a promising PET imaging agent for prostate cancer.


Assuntos
Bombesina/química , Radioisótopos de Flúor/química , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Compostos Heterocíclicos/química , Compostos Heterocíclicos com 1 Anel , Humanos , Masculino , Camundongos , Neoplasias da Próstata/patologia , Radiografia
12.
Amino Acids ; 46(6): 1481-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24633452

RESUMO

Bombesin (BBN) is a peptide exhibiting high affinity for the gastrin-releasing peptide receptor (GRPR), which is overexpressed on several types of cancers. Various GRPR antagonists and agonists have been labeled with radiometals for positron emission tomography (PET) imaging of GRPR-positive tumors. However, unfavorable hepatobiliary excretion such as high intestinal activity may prohibit their clinical utility for imaging abdominal cancer. In this study, the modified BBN peptide with a new hydrophilic linker was labeled with (68)Ga for PET imaging of GRPR-expressing PC-3 prostate cancer xenograft model. GRPR antagonists, MATBBN (Gly-Gly-Gly-Arg-Asp-Asn-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHCH2CH3) and ATBBN (D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHCH2CH3), were conjugated with 1,4,7-triazacyclononanetriacetic acid (NOTA) and labeled with (68)Ga. Partition coefficient and in vitro stability were also determined. GRPR binding affinity of both tracers was investigated by competitive radioligand binding assay. The in vivo receptor targeting potential and pharmacokinetic of (68)Ga-NOTA-MATBBN were also evaluated in PC-3 prostate tumor model and compared with those of (68)Ga-NOTA-ATBBN. NOTA-conjugated BBN analogs were labeled with (68)Ga within 20 min with a decay-corrected yield ranging from 90 to 95 % and a radiochemical purity of more than 98 %. The specific activity of (68)Ga-NOTA-MATBBN and (68)Ga-NOTA-ATBBN was at least 16.5 and 11.9 GBq/µmol, respectively. The radiotracers were stable in phosphate-buffered saline and human serum. (68)Ga-NOTA-MATBBN was more hydrophilic than (68)Ga-NOTA-ATBBN, as indicated by their log P values (-2.73 ± 0.02 vs. -1.20 ± 0.03). The IC50 values of NOTA-ATBBN and NOTA-MATBBN were similar (102.7 ± 1.18 and 124.6 ± 1.21 nM). The accumulation of (68)Ga-labeled GRPR antagonists in the subcutaneous PC-3 tumors could be visualized via small animal PET. The tumors were clearly visible, and the tumor uptakes of (68)Ga-NOTA-MATBBN and (68)Ga-NOTA-ATBBN were determined to be 4.19 ± 0.32, 4.00 ± 0.41, 2.93 ± 0.35 and 4.70 ± 0.40, 4.10 ± 0.30, 3.14 ± 0.30 %ID/g at 30, 60, and 120 min, respectively. There was considerable accumulation and retention of (68)Ga-NOTA-ATBBN in the liver and intestines. In contrast, the abdominal area does not have much retention of (68)Ga-NOTA-MATBBN. Biodistribution data were in accordance with the PET results, showing that (68)Ga-NOTA-MATBBN had more favorable pharmacokinetics and higher tumor to background ratios than those of (68)Ga-NOTA-ATBBN. At 1 h postinjection, the tumor to liver and intestine of (68)Ga-NOTA-MATBBN were 8.05 ± 0.56 and 21.72 ± 3.47 and the corresponding values of unmodified counterpart were 0.85 ± 0.23 and 3.45 ± 0.43, respectively. GRPR binding specificity was demonstrated by reduced tumor uptake of radiolabeled tracers after coinjection of an excess of unlabeled BBN peptides. (68)Ga-NOTA-MATBBN exhibited GRPR-targeting properties both in vitro and in vivo. The favorable characterizations of (68)Ga-NOTA-MATBBN such as convenient synthesis, specific GRPR targeting, high tumor uptake, and satisfactory pharmacokinetics warrant its further investigation for clinical cancer imaging.


Assuntos
Bombesina/metabolismo , Radioisótopos de Gálio , Marcação por Isótopo/métodos , Receptores da Bombesina/metabolismo , Animais , Bombesina/análogos & derivados , Linhagem Celular Tumoral , Compostos Heterocíclicos/química , Compostos Heterocíclicos com 1 Anel , Xenoenxertos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/metabolismo , Distribuição Tecidual
13.
Cytokine ; 61(2): 394-405, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23294974

RESUMO

OBJECTIVE: To demonstrate the hypothesis that aerobic exercise training inhibits the development of insulin resistance through IL-6 and probe into the possible molecular mechanism about it. METHODS: Rats were raised with high-fat diets for 8 weeks to develop insulin resistance, and glucose infusion rates (GIRs) were determined by hyperinsulinemic-euglycemic clamping to confirm the development of insulin resistance. Aerobic exercise training (the speed and duration time in the first week were respectively 16 m/min and 50 min, and speed increased 1m/min and duration time increased 5 min every week following it) and/or IL-6shRNA plasmid injection (rats received IL-6shRNA injection via the tail vein every two weeks) were adopted during the development of insulin resistance. The serum IL-6, leptin, adiponectin, fasting blood glucose, fasting serum insulin, GIR, IL-6 gene expression levels, p-p38 in various tissues and p-STAT3/t-STAT3 ratio in the liver were measured. RESULTS: Rats fed with high-fat diets for 8 weeks were developed insulin resistance and the IL-6mRNA levels of IL-6shRNA injection groups in various tissues were significantly lower than those of control group (P<0.05), respectively. The development of insulin resistance in exercise rats significantly decreased, however, compared with that, the GIR of exercise rats injected by IL-6shRNA was lower (P<0.05). The IL-6mRNA levels were highest in the fat tissue and lowest in the skeletal muscles in all the rats. The serum adiponectin levels decreased (P<0.05) following the development of insulin resistance, and it increased (P<0.05) when the rats were intervened by aerobic exercise training for 8 weeks at the same time. However, there were not significant differences when serum leptin concentrations were compared (P>0.05). The p-p38 significantly increased in the rats fed with high-fat diets, however, p-p38 of the exercise high-fat diets rats in the liver and fat tissues significantly decreased than that (P<0.05). The changes of p-p38 in exercise rats injected by IL-6shRNA were irregular. The activation of STAT3 in the liver significantly increased (P<0.05) following the development of insulin resistance, and it decreased (P<0.05) when the rats were intervened by aerobic exercise training for 8 weeks at the same time, and the gene silencing of IL-6 did not have effects on the activation of STAT3 in the liver (P>0.05). CONCLUSIONS: In conclusion, aerobic exercise training prevented the development of insulin resistance through IL-6 to a certain degree. The gene expression and secretion of IL-6 could inhibit the development of insulin resistance. The mechanism of the effects were possibly related with elevating the levels of serum adiponectin, and/or inhibiting the activation of STAT3 in the liver and p38MAPK in the skeletal muscles, liver and fat tissues.


Assuntos
Regulação da Expressão Gênica , Resistência à Insulina/genética , Interleucina-6/genética , Condicionamento Físico Animal , Interferência de RNA , Adiponectina/sangue , Animais , Dieta Hiperlipídica , Interleucina-6/sangue , Leptina/sangue , Fígado/metabolismo , Masculino , Músculo Esquelético/metabolismo , Plasmídeos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Transcrição STAT3/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno
14.
Neurosci Lett ; 517(1): 30-5, 2012 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-22516465

RESUMO

Intracellular second messengers play an important role in capsaicin- and analogous-induced sensitization and desensitization in pain. Fluorescence Ca²âº imaging, enzyme immunoassay and PKC assay kit were used to determine a novel mechanism of different Ca²âº dependency in the signal transduction of capsaicin-induced desensitization. On the average, capsaicin increased cAMP, cGMP concentration and SP release in bell-shaped concentration-dependent manner, with the maximal responses at concentrations around 1 µM, suggesting acute desensitization of TRPV1 receptor activation. Capsaicin-induced intracellular Ca²âº concentration ([Ca²âº](i)) increase depended on extracellular Ca²âº influx as an initial trigger. The Ca²âº influx by capsaicin increased PKC activation and SP release. These increases were completely abolished in Ca²âº-free solution, suggesting that the modulation of capsaicin on PKC and SP are Ca²âº-dependent. Interestingly, the maximal cAMP increase by TRPV1 activation was not blocked Ca²âº removal, suggesting at least in part a Ca²âº-independent pathway is involved. Further study showed that cAMP increase was totally abolished by G-protein and adenylate cyclase (AC) antagonist, suggesting a G-protein-dependent pathway in cAMP increase. However, SP release was blocked by inhibiting PKC, but not G-protein or AC, suggesting a G-protein independent pathway in SP release. These results suggest that both Ca²âº-dependent and independent mechanisms are involved in the regulation of capsaicin on second messengers systems, which could be a novel mechanism underlying distinct desensitization of capsaicin and might provide additional opportunities in the development of effective analgesics in pain treatment.


Assuntos
Cálcio/metabolismo , Capsaicina/farmacologia , Neurônios/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Canais de Cátion TRPV/fisiologia , Animais , Capsaicina/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Masculino , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Substância P/metabolismo
15.
Zhonghua Fu Chan Ke Za Zhi ; 47(1): 14-8, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22455687

RESUMO

OBJECTIVE: To investigate clinical effect and safety of in vitro maturation (IVM) of human immature oocytes in infertile women with polycystic ovary syndrome by comparing with conventional in vitro fertilization(IVF)and intracytoplasmic sperm injection(ICSI). METHODS: From Jan. 2003 to Dec. 2009, 157 infertile women with PCOS underwent 162 cycles IVM in Center for Reproductive Medicine, the First Affiliated Hospital of Anhui Medical University. In the mean time, 109 patients with PCOS underwent 114 IVF/ICSI cycles as control group 1 and 106 patients with other factors underwent 106 IVF/ICSI cycles as control group 2. Treatment and outcome of pregnancy and infant were compared among those 3 groups. RESULTS: No statistically significant difference were found in terms of the positive rate of hCG in urine [35.7% (56/157), 42.2% (46/109), 44.3% (47/106)], the rate of clinical pregnancy [29.3% (46/157), 37.6% (41/109), 41.5% (44/106)], the rate of entopic pregnancy [1.9% (3/157), 1.8% (2/109), 0.9% (1/106)], the rate of miscarriage [18.6% (8/43), 12.8% (5/39), 20.9% (9/43)] and the rate of live-birth [22.3% (35/157), 31.2% (34/109), 32.1% (34/106)] among three groups (IVM group, control group 1, control group 2, P > 0.05). The rate of preterm labor, low weight newborn, mean birth weight, ratio of male to female did not show significantly difference among 3 groups (P > 0.05). The average control ovarian stimulation was 6 days, the median dose of gonadotropin (Gn) was 675 IU, and the total hospital cost was (8392 ± 1328) RMB in IVM group, which were statistically lower than those in the other two control groups (P < 0.01). The rate of multiple pregnancy was 4.7% (2/43) and ovarian hyperstimulation syndrome (OHSS) 0 in IVM group, which were significantly lower than those in the other control group (P < 0.01). CONCLUSION: In vitro maturation is an effective treatment in infertile women with PCOS, it could obtain the similar pregnancy outcome and reduce total cost, the dosage of gonadotropin-releasing hormone and rate of OHSS compared with conventional IVF/ICSI.


Assuntos
Infertilidade Feminina/terapia , Oócitos/fisiologia , Síndrome do Ovário Policístico/terapia , Técnicas de Reprodução Assistida , Adulto , Peso ao Nascer , Estudos de Casos e Controles , Técnicas de Cultura de Células , Células Cultivadas , Transferência Embrionária , Feminino , Fertilização In Vitro , Humanos , Recém-Nascido , Infertilidade Feminina/etiologia , Masculino , Oócitos/citologia , Oogênese , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/complicações , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
16.
Appl Radiat Isot ; 70(4): 583-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22245365

RESUMO

OBJECTIVE: The purpose of this study was to investigate the therapy effects of intratumoral administration of (32)P-CP-PLLA particles in a rabbit VX2 lung tumor model. METHODS: 16 rabbits with tumors were randomly divided into 4 groups. 4 rabbits served as untreated controls, and others received intratumoral administration of (32)P-CP-PLLA particles with CT guidance. The total radioactivities in treated groups were as follows: a low activity was 93 MBq (n=4) (group 1), a medium activity was 185 MBq (n=4) (group 2) and a high activity was 370 MBq (n=4) (group 3). Brachytherapy treated VX2 tumors underwent (18)F-FDG PET/CT at 0 day, 3 day, 7 day and 14 day postinjection. In control group, (18)F-FDG PET/CT images were acquired at the same time points but without any treatment. Bremsstrahlung SPECT images were performed at 14 days after intratumoral brachytherapy in treated groups. After Bremsstrahlung SPECT and last (18)F-FDG PET/CT imagings, the rabbits were euthanized and the tumors were removed for histological examination. RESULTS: Bremsstrahlung SPECT images study indicated that there was no leakage of (32)P out of the injection site at 14 days after treatment. Compared with the control, the tumor volumes in treated groups significantly decreased, and (32)P-CP-PLLA particle produced a reduction in maximum or mean SUV of VX2 tumor (p<0.05). The percentage changes in maximum and mean SUV gradually decreased in group 1 and group 2 from day 3 to day 14 (p<0.05). A transient increase in (18)F-FDG accumulation at group 3 occurred due to the inflammatory reaction elements. Activity dependence was seen in HE and PCNA staining after 14 days treatment among three treated groups (p<0.05). CONCLUSIONS: Our data suggested that (32)P-CP-PLLA particle localized on the injecting sites. This novel brachytherapy device efficiently suppressed the growth of the VX2 tumors implanted in the rabbit.


Assuntos
Braquiterapia/métodos , Ácido Láctico/administração & dosagem , Neoplasias Pulmonares/radioterapia , Radioisótopos de Fósforo/uso terapêutico , Polímeros/administração & dosagem , Animais , Modelos Animais de Doenças , Fluordesoxiglucose F18 , Ácido Láctico/uso terapêutico , Neoplasias Pulmonares/diagnóstico por imagem , Radioisótopos de Fósforo/administração & dosagem , Poliésteres , Polímeros/uso terapêutico , Coelhos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/uso terapêutico , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos
17.
Zhonghua Fu Chan Ke Za Zhi ; 45(3): 191-6, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20450755

RESUMO

OBJECTIVE: To investigate the association between polymorphism of cytochrome P450 subfamily XIA polypeptide 1 (CYP11A1) gene and polycystic ovarian syndrome (PCOS) in Chinese population. METHODS: From May 2005 to Dec. 2008, 290 PCOS cases treated in the First affiliated hospital of Anhui Medical University matched with 344 reproductive women as controls were enrolled in this study. Genotypes of 7 tagging single nucleotide polymorphisms (tSNP, rs12438594, rs4077582, rs9806234, rs16968477, rs4887139, rs1843090, rs11632698) covering CYP11A1 gene (r(2) > or = 0.8) and 3 microsatellite markers (D15S1547, D16S520, D15S1546) were chosed from the phase II database of Han population in HapMap data. Genotype and frequency of allele were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and haplotype of gene polymorphism were analyzed in 290 PCOS cases and 344 controls. RESULTS: Among 7 tSNPs and 3 microsatellite markers, the frequency of rs4077582, D15S1547, D15S1546 and rs11632698 between two groups reached statistical difference (P = 0.010, 0.044, 0.018 and 0.026). The allele frequency of rs4077582, rs4887139, rs1843090, D15S1547 and D16S520 showed significant difference between two groups (P = 0.002, 0.048, 0.030, 0.001 and 0.024). Among 5 haplotype of CYP11A1 (ACGCA13/6/9AG, ACGTA16/6/11AA, GCACG12/8/8AA, GTACA14/4/7GG, GTGCA13/6/7AG), the frequency of GTACA14/4/7GG and ACGCA13/6/9AG were 7.8% (45/580) and 25.3% (147/580) in PCOS group and 11.9% and 19.6% in control group, which showed statistical difference (P < 0.05). There was no significant difference in the level of serum androgen at difference genotype from rs4077582 between two groups (P > 0.05). CONCLUSION: The polymorphism of CYP11A1 gene was associated with PCOS, however, the relationship between gene sequence covered by tSNP/microsatellite markers and hyperandrogenism of PCOS should be further investigated.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Repetições de Microssatélites , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Estudos de Casos e Controles , China/etnologia , Primers do DNA , Estradiol/sangue , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Síndrome do Ovário Policístico/etnologia , Reação em Cadeia da Polimerase/métodos , Testosterona/sangue , Adulto Jovem
18.
Int J Biochem Cell Biol ; 41(11): 2240-50, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19427400

RESUMO

Neurofibromatosis type 1 (NF1) microdeletion is a large genomic deletion that embraces at least 11 continuous genes at human chromosome 17q11.2. To date, most of these genes' functions still remain undefined. In this study, we report an unknown cytokine receptor like molecule (p48.2) that is frequently deleted in patients with type-1 and type-2 NF1 microdeletions in the neurofibromin locus. The cloned gene has 1317 base pair long that encodes a 438aa intracellular protein. The gene was subsequently named p48.2 based on its predicted molecular weight. A typical fibronectin type III (FNIII) domain was identified in p48.2 between Arg(176) and Pro(261) in which a palindromic Arg-Gly-Asp (RGD) repeat plus a putative Trp-Ser-X-Trp-Ser (WSXWS) motif were found at the domain's C-terminus. p48.2 mRNAs were abundant in many tumor cell lines and normal human tissues and up-regulated in some freshly isolated lung cancer and leukemia cells. Interestingly, over-expression of p48.2 in human embryo kidney 293T cells could significantly cause G0/G1 arrest and prevented S phase entry. In contrast, repressing endogenous p48.2 gene expression by specific siRNA markedly reduced G0/G1 population. Importantly, over-expression of p48.2 could significantly up-regulate rather than down-regulate cyclin D1 and cyclin D3 expressions. We further showed that the induction of cyclin D1 expression was directly due to the activation of signal transducers and activators of transcription 3 (STAT3), but was independent of RAS/mitogen-activated protein kinase (RAS/MAPK) signaling pathway. Thus, p48.2 may represent a novel type of intracellular protein functioning as a negative regulator at the G0/G1 phase.


Assuntos
Proteínas de Ciclo Celular/genética , Ciclo Celular , Espaço Intracelular/metabolismo , Receptores de Citocinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Ciclo Celular/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Clonagem Molecular , Biologia Computacional , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclina D3/genética , Ciclina D3/metabolismo , Regulação para Baixo/genética , Fase G1 , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genoma Humano/genética , Humanos , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno , Receptores de Citocinas/química , Receptores de Citocinas/metabolismo , Fase de Repouso do Ciclo Celular , Fator de Transcrição STAT3/metabolismo , Homologia de Sequência de Aminoácidos , Transdução de Sinais
19.
Appl Radiat Isot ; 67(4): 594-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19181532

RESUMO

This work reports the synthesis, radiolabeling and preliminary in vitro evaluation of [(131)I]-5-iodo-N-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-yl)-ethyl]-2-methoxy-benzamide. The tributylstannylprecursor was synthesized with a yield of 38%. Radiolabeling was performed using an electrophilic iododestannylation. Tracer yield was 94%, radiochemical purity was >95%. The tracer showed high uptake in MCF-7 breast cancer cell line and therefore will be evaluated further.


Assuntos
Benzamidas/síntese química , Radioisótopos do Iodo , Isoquinolinas/síntese química , Neoplasias/diagnóstico por imagem , Compostos Radiofarmacêuticos/síntese química , Linhagem Celular Tumoral , Humanos , Espectroscopia de Ressonância Magnética , Cintilografia , Espectrometria de Massas por Ionização por Electrospray
20.
Artigo em Chinês | MEDLINE | ID: mdl-21141527

RESUMO

AIM: To study the regulation mechanism of GP on plasma lipoprotein metabolism and To explore its mechanism of anti-lipoperoxidation in the experimental hyperglycemia rats. METHODS: The rats were raised with high fat diet for six weeks,and the model of hyperglycemia was then established. After that, those rats were treated with high or low dose of GP and xuezhikang as a masculine comparison for four weeks. Then, those rat were executed, and detected the plasma TC, TG, LDL-C, HDL-C, GSH-Px, at the same time the SOD, CAT and MDA concentration also be mensurated. RESULTS: The results showed that high and low dose of GP could decrease the concentration of serum LDL-C, cholesterol and triglyceride remarkably and raise the concentration of HDL-C. The activity of GSH-Px, SOD and CAT in GP groups were promoted and the level of MDA was decreased distinctly. CONCLUSION: The GP can therapy the abnormity of serum lipid and has obviously anti-lipoperoxidation affection.


Assuntos
Hiperlipidemias/metabolismo , Lipídeos/sangue , Fitoterapia , Animais , Colesterol/sangue , LDL-Colesterol/sangue , Gynostemma , Hiperlipidemias/tratamento farmacológico , Peroxidação de Lipídeos , Lipoproteínas HDL/sangue , Masculino , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Triglicerídeos/sangue
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