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1.
Ann Neurol ; 96(1): 194-203, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38661030

RESUMO

OBJECTIVE: Primary angiitis of the central nervous system (PACNS) is a rare vasculitis restricted to the brain, spinal cord, and leptomeninges. This study aimed to describe the imaging characteristics of patients with small vessel PACNS (SV-PACNS) using 7 T magnetic resonance imaging (MRI). METHODS: This ongoing prospective observational cohort study included patients who met the Calabrese and Mallek criteria and underwent 7 T MRI scan. The MRI protocol includes T1-weighted magnetization-prepared rapid gradient echo imaging, T2 star weighted imaging, and susceptibility-weighted imaging. Two experienced readers independently reviewed the neuroimages. Clinical data were extracted from the electronic patient records. The findings were then applied to a cohort of patients with large vessel central nervous system (CNS) vasculitis. RESULTS: We included 21 patients with SV-PACNS from December 2021 to November 2023. Of these, 12 (57.14%) had cerebral cortical microhemorrhages with atrophy. The pattern with microhemorrhages was described in detail based on the gradient echo sequence, leading to the identification of what we have termed the "coral-like sign." The onset age of patients with coral-like sign (33.83 ± 9.93 years) appeared younger than that of patients without coral-like sign (42.11 ± 14.18 years) (P = 0.131). Furthermore, the cerebral lesions in patients with cortical microhemorrhagic SV-PACNS showed greater propensity toward bilateral lesions (P = 0.03). The coral-like sign was not observed in patients with large vessel CNS vasculitis. INTERPRETATION: The key characteristics of the coral-like sign represent cerebral cortical diffuse microhemorrhages with atrophy, which may be an important MRI pattern of SV-PACNS. ANN NEUROL 2024;96:194-203.


Assuntos
Imageamento por Ressonância Magnética , Vasculite do Sistema Nervoso Central , Humanos , Masculino , Feminino , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Vasculite do Sistema Nervoso Central/patologia , Vasculite do Sistema Nervoso Central/complicações , Adulto , Pessoa de Meia-Idade , Estudos Prospectivos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/patologia , Adulto Jovem , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Estudos de Coortes , Adolescente
2.
J Virol ; 97(6): e0041223, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37255475

RESUMO

Pseudorabies virus (PRV) is a double-stranded DNA virus that causes Aujeszky's disease and is responsible for economic loss worldwide. Transmembrane protein 41B (TMEM41B) is a novel endoplasmic reticulum (ER)-localized regulator of autophagosome biogenesis and lipid mobilization; however, the role of TMEM41B in regulating PRV replication remains undocumented. In this study, PRV infection was found to upregulate TMEM41B mRNA and protein levels both in vitro and in vivo. For the first time, we found that TMEM41B could be induced by interferon (IFN), suggesting that TMEM41B is an IFN-stimulated gene (ISG). While TMEM41B knockdown suppressed PRV proliferation, TMEM41B overexpression promoted PRV proliferation. We next studied the specific stages of the virus life cycle and found that TMEM41B knockdown affected PRV entry. Mechanistically, we demonstrated that the knockdown of TMEM41B blocked PRV-stimulated expression of the key enzymes involved in lipid synthesis. Additionally, TMEM41B knockdown played a role in the dynamics of lipid-regulated PRV entry-dependent clathrin-coated pits (CCPs). Lipid replenishment restored the CCP dynamic and PRV entry in TMEM41B knockdown cells. Together, our results indicate that TMEM41B plays a role in PRV infection via regulating lipid homeostasis. IMPORTANCE PRV belongs to the alphaherpesvirus subfamily and can establish and maintain a lifelong latent infection in pigs. As such, an intermittent active cycle presents great challenges to the prevention and control of PRV disease and is responsible for serious economic losses to the pig breeding industry. Studies have shown that lipids play a crucial role in PRV proliferation. Thus, the manipulation of lipid metabolism may represent a new perspective for the prevention and treatment of PRV. In this study, we report that the ER transmembrane protein TMEM41B is a novel ISG involved in PRV infection by regulating lipid synthesis. Therefore, our findings indicate that targeting TMEM41B may be a promising approach for the development of PRV vaccines and therapeutics.


Assuntos
Herpesvirus Suídeo 1 , Proteínas de Membrana , Pseudorraiva , Replicação Viral , Animais , Herpesvirus Suídeo 1/fisiologia , Interferons/metabolismo , Lipídeos , Suínos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
3.
Vet Res ; 55(1): 68, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807225

RESUMO

Pseudorabies virus (PRV) is recognized as the aetiological agent responsible for Aujeszky's disease, or pseudorabies, in swine populations. Rab6, a member of the small GTPase family, is implicated in various membrane trafficking processes, particularly exocytosis regulation. Its involvement in PRV infection, however, has not been documented previously. In our study, we observed a significant increase in the Rab6 mRNA and protein levels in both PK-15 porcine kidney epithelial cells and porcine alveolar macrophages, as well as in the lungs and spleens of mice infected with PRV. The overexpression of wild-type Rab6 and its GTP-bound mutant facilitated PRV proliferation, whereas the GDP-bound mutant form of Rab6 had no effect on viral propagation. These findings indicated that the GTPase activity of Rab6 was crucial for the successful spread of PRV. Further investigations revealed that the reduction in Rab6 levels through knockdown significantly hampered PRV proliferation and disrupted virus assembly and egress. At the molecular level, Rab6 was found to interact with the PRV glycoproteins gB and gE, both of which are essential for viral assembly and egress. Our results collectively suggest that PRV exploits Rab6 to expedite its assembly and egress and identify Rab6 as a promising novel target for therapeutic treatment for PRV infection.


Assuntos
Herpesvirus Suídeo 1 , Montagem de Vírus , Liberação de Vírus , Proteínas rab de Ligação ao GTP , Animais , Camundongos , Linhagem Celular , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/metabolismo , Pseudorraiva/virologia , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Suínos , Doenças dos Suínos/virologia , Montagem de Vírus/genética , Liberação de Vírus/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-38289442

RESUMO

Time-of-death extrapolation has always been one of the most important issues in forensic practice. For a complicated case in which a corpse is destroyed with little evidence, judging the time of death of the deceased is a major challenge, which also enables criminals to escape legal sanctions. To find a method to roughly judge the time of death of a corpse with only a small amount of skin tissue, in this study, we established an early death model by using mice; furthermore, the postmortem interval was estimated by determining the protein and mRNA levels of Bax and Bcl-2 in the skin. In this process, 0 h after death was used as the control group, and the expression levels of Bax and Caspase-3 reached the maximum value at 8-12 h, while Bcl-2, as an inhibitor of apoptosis protein, peaked after 24 h. The mRNA expression levels of related proteins in postmortem skin tissues were also different. The results of these data indicate that the protein and mRNA levels of Bax and Bcl-2 in the skin have potential application in early time-of-death estimation.

5.
Acta Pharmacol Sin ; 44(11): 2282-2295, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37280363

RESUMO

Abnormalities of FGFR1 have been reported in multiple malignancies, suggesting FGFR1 as a potential target for precision treatment, but drug resistance remains a formidable obstacle. In this study, we explored whether FGFR1 acted a therapeutic target in human T-cell acute lymphoblastic leukemia (T-ALL) and the molecular mechanisms underlying T-ALL cell resistance to FGFR1 inhibitors. We showed that FGFR1 was significantly upregulated in human T-ALL and inversely correlated with the prognosis of patients. Knockdown of FGFR1 suppressed T-ALL growth and progression both in vitro and in vivo. However, the T-ALL cells were resistant to FGFR1 inhibitors AZD4547 and PD-166866 even though FGFR1 signaling was specifically inhibited in the early stage. Mechanistically, we found that FGFR1 inhibitors markedly increased the expression of ATF4, which was a major initiator for T-ALL resistance to FGFR1 inhibitors. We further revealed that FGFR1 inhibitors induced expression of ATF4 through enhancing chromatin accessibility combined with translational activation via the GCN2-eIF2α pathway. Subsequently, ATF4 remodeled the amino acid metabolism by stimulating the expression of multiple metabolic genes ASNS, ASS1, PHGDH and SLC1A5, maintaining the activation of mTORC1, which contributed to the drug resistance in T-ALL cells. Targeting FGFR1 and mTOR exhibited synergistically anti-leukemic efficacy. These results reveal that FGFR1 is a potential therapeutic target in human T-ALL, and ATF4-mediated amino acid metabolic reprogramming contributes to the FGFR1 inhibitor resistance. Synergistically inhibiting FGFR1 and mTOR can overcome this obstacle in T-ALL therapy.


Assuntos
Aminoácidos , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Fator 4 Ativador da Transcrição/metabolismo
6.
J Sci Food Agric ; 103(7): 3531-3539, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36788119

RESUMO

BACKGROUND: Manganese (Mn) is an essential micronutrient for plants, whereas excess Mn(II) in soils leads to its toxicity to crops. Mn(II) is adsorbed onto plant roots from soil solution and then absorbed by plants. Root charge characteristics should affect Mn(II) toxicity to crops and Mn(II) uptake by the roots of the crops. However, the differences in the effects of root surface charge on the uptake of Mn(II) among various crop species are not well understood. RESULTS: The roots of nine legumes and six non-legume poaceae were obtained by hydroponics and the streaming potential method and spectroscopic analysis were used to measure the zeta potentials and functional groups on the roots, respectively. The results indicate that the exchangeable Mn(II) adsorbed by plant roots was significantly positively correlated with the Mn(II) accumulated in plant shoots. Legume roots carried more negative charges and functional groups than non-legume poaceae roots, which was responsible for the larger amounts of exchangeable Mn(II) on legume roots in 2 h and the Mn(II) accumulated in their shoots in 48 h. Coexisting cations, such as Ca2+ and Mg2+ , were most effective in decreasing Mn(II) taken up by roots and accumulated in shoots than K+ and Na+ . This was because Ca2+ and Mg2+ could compete with Mn(II) for active sites on plant roots more strongly compared to K+ and Na+ . CONCLUSION: The root surface charge and functional groups are two important factors influencing Mn(II) uptake by roots and accumulation in plant shoots. © 2023 Society of Chemical Industry.


Assuntos
Fabaceae , Poaceae , Manganês , Transporte Biológico , Produtos Agrícolas , Verduras , Solo , Raízes de Plantas
7.
Future Oncol ; 18(30): 3463-3470, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36069254

RESUMO

Colorectal cancer is one of the most malignant cancers worldwide, and efforts have been made to elucidate the mechanism of colorectal carcinogenesis. Cellular senescence is a physiological process in cell life, but it is also found in cancer initiation and progression. Lines of evidence show that senescence may influence the development and progression of colorectal carcinogenesis. Here, the authors review the characteristics of senescence and the recent findings of a relationship between senescence and colorectal cancer.


Cancer is a leading cause of death worldwide; out of the top ten most common cancers in 2020, the incidence and mortality rate of colorectal cancer (CRC) ranked third and second, respectively. Based on statistics, it was estimated that more than 1.9 million CRC cases occurred in 2020. In terms of CRC, a prominent risk factor is age, and studies suggest that the aging process plays a role in CRC initiation and progression. This review discusses how aging contributes to CRC carcinogenesis and summarizes recent findings on potential therapeutics.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Senescência Celular , Carcinogênese
8.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4015-4024, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046890

RESUMO

In this study, the critical quality attributes of Wuzhuyu Decoction reference sample were explored by using characteristic chromatogram, index component content and dry extract rate as indexes.The dissemination relationship of quantity value between medicinal materials-decoction pieces-reference sample was investigated to preliminarily formulate the quality standard of the reference sample.The characteristic chromatogram of 15 batches of Wuzhuyu Decoction was established by high performance liquid chromatography(HPLC) and the similarity analysis was conducted.Common peaks were demarcated and assigned to medicinal materials.Moreover, quantitative determination of limonin, evodiamine, rutaecarpine and ginsenoside Rb_1 of Wuzhuyu Decoction were performed.The dissemination of quantity value was explored combined with dry extract rate, similarity of characteristic chromatogram and transfer rate of index component content.A total of 18 common peaks were identified in the corresponding materials of Wuzhuyu Decoction reference sample, with the similarity of characteristic chromatogram greater than 0.9, and Fructus Evodiae, Radix Ginseng, Rhizoma Zingiberis Recens and Fructus Jujubae contributed 9, 5, 8 and 2 chromatographic peaks, respectively.The index component content of corresponding materials and the transfer rates of medicinal materials-decoction pieces and decoction pieces-reference sample of different batches of Wuzhuyu Decoction reference sample were as follows: the content of limonin was 0.16%-0.51%, and the transfer rates were 83.66%-115.60% and 38.54%-54.58%, respectively; the content of evodiamine was 0.01%-0.11%, the transfer rated were 80.80%-116.15% and 3.23%-12.93%, respectively; the content of rutaecarpine was 0.01%-0.05%, the transfer rates were 84.33%-134.53% and 5.72%-21.24%, respectively; the content of ginsenoside Rb_1 was 0.06%-0.11%, and the transfer rates were 90.00%-96.92% and 32.45%-67.24%, respectively.The dry extract rate of the whole prescription was 22.58%-29.89%.In this experiment, the dissemination of quantity value of Wuzhuyu Decoction reference sample was analyzed by the combination of characteristic chromatogram, index component content and dry extract rate.A scientific and stable quality evaluation method of the reference sample was preliminarily established, which provided basis for the subsequent development of Wuzhuyu Decoction and the quality control of related preparations.


Assuntos
Medicamentos de Ervas Chinesas , Ginsenosídeos , Limoninas , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Ginsenosídeos/análise , Limoninas/análise , Controle de Qualidade
9.
Proc Natl Acad Sci U S A ; 115(16): 4218-4222, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29610342

RESUMO

Reactive oxygen species formed within the mammalian cell can produce 8-oxo-7,8-dihydroguanine (8-oxoG) in mRNA, which can cause base mispairing during gene expression. Here we found that administration of 8-oxoGTP in MTH1-knockdown cells results in increased 8-oxoG content in mRNA. Under this condition, an amber mutation of the reporter luciferase is suppressed. Using second-generation sequencing techniques, we found that U-to-G changes at preassigned sites of the luciferase transcript increased when 8-oxoGTP was supplied. In addition, an increased level of 8-oxoG content in RNA induced the accumulation of aggregable amyloid ß peptides in cells expressing amyloid precursor protein. Our findings indicate that 8-oxoG accumulation in mRNA can alter protein synthesis in mammalian cells. Further work is required to assess the significance of these findings under normal physiological conditions.


Assuntos
Guanina/análogos & derivados , Mutagênese/genética , Biossíntese de Proteínas/genética , Transcrição Gênica/genética , Peptídeos beta-Amiloides/genética , Anticódon/genética , Pareamento de Bases , Códon sem Sentido , Enzimas Reparadoras do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/genética , Técnicas de Silenciamento de Genes , Genes Reporter , Guanina/química , Células HeLa , Humanos , Luciferases/genética , Monoéster Fosfórico Hidrolases/antagonistas & inibidores , Monoéster Fosfórico Hidrolases/genética , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio
10.
Ecotoxicol Environ Saf ; 223: 112547, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34330039

RESUMO

Excessive amounts of copper (Cu) in soils causes toxic effects on plants. In this study, 58 rice cultivars were classified into tolerant, moderately tolerant, and susceptible types for Cu(II) toxicity based on 50% germination (LC50). Nine japonica rice varieties (three each from the tolerant, moderately tolerant, and susceptible groups) and six indica rice varieties (three from the moderately tolerant and susceptible groups) were selected for the hydroponics experiments. In the short-term adsorption experiment, Cu(II) adsorbed on rice roots was differentiated into exchangeable, complexed, and precipitated forms. Similarly, it was done for long-term culture. Absorption of Cu(II) by rice roots and shoots was also measured. The results indicated that adsorbed Cu(II) mainly existed as complexed and exchangeable forms on rice roots in the short-term adsorption experiment, and the exchangeable and complexed Cu(II) levels were greater for indica rice than for japonica rice due to the larger negative charge on the indica rice roots. The adsorbed Cu(II) mainly existed as a complexed form in the long-term culture experiment, and the exchangeable Cu(II) level was much lower than that in the short-term adsorption experiment due to the absorption of Cu(II) by rice plants. The indica varieties absorbed more Cu(II) than the japonica varieties. Furthermore, the absorption and accumulation of Cu(II) by the susceptible varieties were greater than by the tolerant and moderately tolerant varieties for both the japonica and indica rice. The absorption and accumulation of Cu(II) in rice roots were much greater than in the shoots. Chlorophyll content, and the lengths and dry matter weights of the rice roots and shoots decreased with increasing Cu(II) concentration. The Cu(II) showed greater toxicity toward indica varieties than japonica varieties, and the greater negative charge on indica roots was one of reasons for the greater exchangeable Cu(II) on the roots, the increase in Cu(II) toxicity, and the higher uptake of Cu(II) by indica rice varieties compared to japonica rice varieties.


Assuntos
Oryza , Poluentes do Solo , Adsorção , Cobre/toxicidade , Solo , Poluentes do Solo/toxicidade
11.
Ecotoxicol Environ Saf ; 207: 111224, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32890955

RESUMO

The roots of 4 japonica, 4 indica, and 7 hybrid rice varieties were obtained by hydroponic experiment and used to explore the relationship between charge characteristics and exchangeable manganese(II) (Mn(II)) on rice roots and Mn(II) absorption in roots and shoots of the rice. Results indicated Mn(II) adsorbed on rice roots mainly existed as exchangeable Mn(II) after 2 h. The roots of indica and hybrid rice carried more negative charges than the roots of japonica rice. Accordingly, this led to more exchangeable Mn(II) to be adsorbed on roots of indica and hybrid rice after 2 h and more Mn(II) absorbed in the roots of the same varieties after 48 h. However, this was contrary to the result of Mn(II) absorption in rice shoots after 48 h. Coexisting cations of K+, Na+, Ca2+, and Mg2+ reduced the exchangeable Mn(II) on rice roots through their competition with Mn(II) for sorption sites on rice roots, which led to the decrease in Mn(II) absorption in rice roots and shoots. Ca2+ and Mg2+ showed a greater decrease in the Mn(II) absorbed in roots and shoots than K+ and Na+. The reduction of Mn(II) absorption in the roots of indica rice and hybrid rice induced by Ca2+ and Mg2+ was more than that of japonica rice. This was attributed to more negative charges on the roots of the former than the latter. Therefore, the absorption of Mn(II) by rice roots was determined by surface charge properties and exchangeable Mn(II) on the rice roots. The results suggested that Ca2+ and Mg2+ have potential to alleviate Mn(II) toxicity to rice.


Assuntos
Manganês/toxicidade , Oryza/metabolismo , Poluentes do Solo/toxicidade , Adsorção , Manganês/metabolismo , Oryza/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Poluentes do Solo/metabolismo
12.
Int J Mol Sci ; 22(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34639075

RESUMO

In this study, interactions of Fe3O4 magnetic nanoparticles with serum albumin biomolecules in aqueous solutions were considered. The studies were conducted with the laser correlation spectroscopy and optical analysis of dehydrated films. It was shown that the addition of magnetite to an albumin solution at low concentrations of up to 10-6 g/L led to the formation of aggregates with sizes of up to 300 nm in the liquid phase and an increase in the number of spiral structures in the dehydrated films, which indicated an increase in their stability. With a further increase in the magnetite concentration in the solution (from 10-4 g/L), the magnetic particles stuck together and to albumin, thus forming aggregates with sizes larger than 1000 nm. At the same time, the formation of morphological structures in molecular films was disturbed, and a characteristic decrease in their stability occurred. Most stable films were formed at low concentrations of magnetic nanoparticles (less than 10-4 g/L) when small albumin-magnetic nanoparticle aggregates were formed. These results are important for characterizing the interaction processes of biomolecules with magnetic nanoparticles and can be useful for predicting the stability of biomolecular films with the inclusion of magnetite particles.


Assuntos
Fenômenos Magnéticos , Agregados Proteicos , Albumina Sérica/química , Albumina Sérica/metabolismo , Algoritmos , Nanopartículas de Magnetita/química , Modelos Teóricos , Tamanho da Partícula , Ligação Proteica , Análise Espectral
13.
Anal Chem ; 92(3): 2417-2424, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31880432

RESUMO

Recent studies have proposed barium isotopes as a novel proxy for studying primary productivity in paleo-oceangraphical studies and elements cycling through the critical zone. Pristine marine carbonates are generally assumed to preserve Ba isotope compositions of ancient seawater. However, Ba incorporated in or adsorbed on detrital minerals such as clays in impure carbonates may limit the accurate application of the Ba isotope proxy for paleo-ocean environmental reconstruction purposes. We present here a sequential extraction procedure and show that a considerable range of Ba concentrations can be associated with the four operationally defined sequential leaching fractions (water-soluble, exchangeable, carbonate, and oxidizable fractions). Chemical separation of Ba from these leachates is achieved with a recovery of >98.6% by our modified ion exchange procedure. Potential instrumental mass bias effects and barium isotope fractionation during the chemical separation are corrected using a carefully optimized 130Ba-135Ba double-spike method. A long-term reproducibility better than ±0.03‰ (2SD) for δ137/134Ba has been achieved by using the double spike-thermal ionization mass spectrometry (DS-TIMS) in this study. We demonstrate that significant variations of δ137/134Ba in the analyzed leachates suggest a considerable Ba isotope fractionation between carbonate mineral phase and noncarbonate phases of marine carbonate rocks. The barium isotope distribution in a set of standard reference materials and natural geological samples under various geological settings has been presented. When utilizing Ba isotopes as a proxy for primary productivity and the biogeochemical cycling of Ba, our new findings from sequential Ba extraction as well as our modified precise DS-TIMS analytical setup should be taken into account.

14.
Ecotoxicol Environ Saf ; 187: 109813, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31644989

RESUMO

To explore the relationship between charge characteristics of rice roots and aluminum (Al) tolerance of rice, roots of 47 different rice genotypes were obtained by hydroponic experiment. The zeta potentials of roots were determined by streaming potential method, and the Al tolerance and the functional groups of rice were measured by relative root elongation and infrared spectroscopy (ATR-FTIR), respectively. The exchangeable, complexed and precipitated Al(III) sorbed on the root surface of rice was extracted with 1 mol L-1 KNO3, 0.05 mol L-1 EDTA-2Na and 0.01 mol L-1 HCl, respectively. There was a significant correlation between the zeta potentials and the relative elongation of rice roots, indicating that the zeta potentials of rice roots could be used to characterize rice tolerance to Al toxicity. Twelve Al-tolerant rice varieties, 25 medium Al-tolerant rice varieties, and 10 Al-sensitive rice varieties were obtained. The Al-tolerant rice varieties sorbed less complexed Al(III) and total Al(III) because there was lower negative charge on their roots compared to less tolerant genotypes. A correlation analysis showed that there were significant negative correlations between the zeta potential, relative root elongation, and the total Al(III) sorption capacity of the roots, which further confirmed the reliability of using the root zeta potential to characterize rice tolerance to Al toxicity. The results of this paper provide a new method for screening Al-tolerant rice varieties.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Alumínio/toxicidade , Oryza/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Solo/química , Adaptação Fisiológica/genética , Eletroquímica , Genótipo , Concentração de Íons de Hidrogênio , Oryza/genética , Oryza/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Especificidade da Espécie , Propriedades de Superfície
15.
Ecotoxicol Environ Saf ; 196: 110545, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276162

RESUMO

The relationship between the chemical forms of Cu2+ and Cd2+ adsorbed on the roots of different wheat cultivars and their phytotoxic effects on the plants were investigated. The wheat varieties Dunmaiwang (DMW), Tekang 6 (TK6), Zhongmai895 (ZM895), and Chaojixiaomai (AK68) were used. The zeta potentials of wheat roots, measured by the streaming potential method, were used to characterize root charge properties. Results indicated that the changes in zeta potential at pH 4.01-6.61 were 14.7, 15.53, 13.01, and 12.06 mV for ZM895, AK68, DMW, and TK6, respectively. The negative charge and functional groups on ZM895 and AK68 roots were greater than on DMW and TK6 roots, which led to more exchangeable and complexed Cu2+ and Cd2+ on ZM895 and AK68 roots and increased Cu2+ and Cd2+ toxicity compared to DMW and TK6. Coexisting cations, such as Ca2+, Mg2+, K+, and NH4+, alleviated Cu2+ and Cd2+ toxicity to wheat roots through competition for adsorption sites on the roots, which decreased exchangeable and complexed Cu2+ and Cd2+ on wheat roots. The Ca2+ and Mg2+ were most effective in alleviating heavy metal toxicity and they decreased exchangeable Cu2+ on AK68 roots by 39.14% and 47.82%, and exchangeable Cd2+ by 8.51% and 28.23%, respectively.


Assuntos
Cádmio/toxicidade , Cobre/toxicidade , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Adsorção , Cádmio/química , Cádmio/farmacocinética , Cátions , Cobre/química , Cobre/farmacocinética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/fisiologia , Poluentes do Solo/química , Poluentes do Solo/farmacocinética , Triticum/metabolismo , Triticum/fisiologia
16.
Mar Drugs ; 17(1)2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30609694

RESUMO

In this report, protein of hairtail (Trichiurus japonicas) muscle was separately hydrolyzed using five kinds of proteases (alcalase, trypsin, neutrase, pepsin, and papain), and the papain- and alcalase-hydrolysates showed higher 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH•) and hydroxyl radical (HO•) scavenging activity than other three protease hydrolysates. Therefore, the protein hydrolysate of hairtail muscle (HTP) was prepared using binary-enzymes hydrolysis process (papain + alcalase). Subsequently, eight antioxidant peptides were purified from HTP using membrane ultrafiltration and chromatography technology, and their amino acid sequences were identified as Gln-Asn-Asp-Glu-Arg (TJP1), Lys-Ser (TJP2), Lys-Ala (TJP3), Ala-Lys-Gly (TJP4), Thr-Lys-Ala (TJP5), Val-Lys (TJP6), Met-Lys (TJP7), and Ile-Tyr-Gly (TJP8) with molecular weights of 660.3, 233.0, 217.1, 274.1, 318.0, 245.1, 277.0, and 351.0 Da, respectively. TJP3, TJP4, and TJP8 exhibited strong scavenging activities on DPPH• (EC50 0.902, 0.626, and 0.663 mg/mL, respectively), HO• (EC50 1.740, 2.378, and 2.498 mg/mL, respectively), superoxide anion radical (EC50 2.082, 2.538, and 1.355 mg/mL, respectively), and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical (EC50 1.652, 0.831, and 0.586 mg/mL, respectively). Moreover, TJP3, TJP4, and TJP8 showed higher reducing power and inhibiting ability on lipid peroxidation in a linoleic acid model system. These results suggested that eight isolated peptides (TJP1 to TJP8), especially TJP3, TJP4, and TJP8 might serve as potential antioxidants applied in the pharmaceutical and health food industries.


Assuntos
Antioxidantes/metabolismo , Peixes/metabolismo , Músculos/metabolismo , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Hidrolisados de Proteína/metabolismo , Aminoácidos/metabolismo , Animais , Antioxidantes/química , Benzotiazóis/química , Compostos de Bifenilo/química , Ácido Linoleico/química , Peroxidação de Lipídeos/efeitos dos fármacos , Fragmentos de Peptídeos/química , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Picratos/química , Hidrolisados de Proteína/química , Ácidos Sulfônicos/química , Superóxidos/metabolismo
17.
Ecotoxicol Environ Saf ; 171: 790-797, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30660972

RESUMO

The continuous production of low molecular weight (LMW) organic acids by plants and microorganisms coupled with the continuous presence of extracellular polymeric substances (EPS) in soils is a guarantee that the mobility of heavy metals in soils will be controlled. The effects of citrate, oxalate, and EPS on the adsorption of Pb by an acidic Ultisol were studied both as a function of pH and ionic strength. Electrokinetic potential measurements were also employed to observe to what extent each ligand affected the surface charge property of the Ultisol. All the ligands shifted the zeta potential of the Ultisol to the negative direction, implying that the surface charge of the soil became more negative. The effect on the zeta potential of the soil was observed in the order of oxalate ˃ citrate ˃ EPS. The quantity of Pb adsorbed at each pH (3.0-7.0) reflected the corresponding change in the zeta potential as induced by each ligand. The presence of the ligands shifted the isoelectric point of the Ultisol from 4.8 to 3.2 for the EPS system and below 3.0 for the citrate and oxalate systems. More Pb was adsorbed in the presence of oxalate than in the presence of citrate and EPS. The two most outstanding mechanisms that governed the adsorption of Pb by the Ultisol were (1) electrostatic attraction which was supported by the increase in negative zeta potential of the Ultisol and, (2) complexation which was supported by the lesser proportion of Pb adsorbed in the citrate system at higher pH and also by the spectroscopic data for EPS. The combination EPS + citrate + oxalate was more effective in enhancing the adsorption of Pb than the combination EPS + oxalate and EPS + citrate.


Assuntos
Ácido Cítrico/química , Matriz Extracelular de Substâncias Poliméricas , Chumbo/química , Oxalatos/química , Pseudomonas fluorescens , Poluentes do Solo/química , Solo/química , Adsorção , Concentração de Íons de Hidrogênio , Concentração Osmolar , Propriedades de Superfície
18.
J Environ Manage ; 236: 446-454, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30769254

RESUMO

Mn-containing sludge from groundwater treatment was converted to magnetic particles (MPs) via a one-step hydrothermal method using sodium ascorbate (SA) as the reductant. The MPs were characterized by X-ray diffraction spectroscopy, Mössbauer spectroscopy, X-ray fluorescence spectroscopy, magnetometry and Gran titration and the results showed that magnetic jacobsite was obtained as an intermediate product in transformation of Fe/Mn oxides to siderite and rhodochrosite. When the molar ratio of SA to Mn in the sludge was two, the produced MPs-2 contained a mixture of ferrihdyrite, hematite, jacobsite and Si/Al oxides, and could magnetize at 2.4 emu/g. Ferrihydrite content in MPs decreased with increase of the SA/Mn molar ratio, leading to decrease of the surface sites concentration (Hs). Thus, MPs-2 contained optimized Hs of 6.7 mmoL/g and a desirable adsorption capacity of Cu(II) (73.1 mg/g). The adsorption isotherms of MPs-2 on Cu(II) complied with the Langmuir model and the adsorption kinetics fitted well with the pseudo-second-order model. The major mechanism of adsorption was cationic exchange of the coordinated H and Na ions on MPs-2 surface sites with the Cu(II) ions. This study was the first time to report preparation of MPs by recycling Mn-containing sludge, which could be used as a high-capacity and low-cost adsorbent in treatment of heavy metal-containing wastewater.


Assuntos
Água Subterrânea , Esgotos , Adsorção , Concentração de Íons de Hidrogênio , Íons , Cinética , Manganês
19.
Int J Health Care Qual Assur ; 32(7): 1055-1071, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411094

RESUMO

PURPOSE: The purposes of this paper are two-fold: first, to introduce a new concept of primary care consultation system at a mainland Chinese hospital in response to healthcare reform; and second, to explore the factors associated with change resistance and acceptance from both patients' and medical staff's perspectives. DESIGN/METHODOLOGY/APPROACH: A survey design study, with two questionnaires developed and distributed to patients and medical staff. Convenience and stratified random sampling methods were applied to patient and medical staff samples. FINDINGS: A 5-dimension, 21-item patient questionnaire and a 4-dimension, 16-item staff questionnaire were identified and confirmed, with 1020 patients (91.07 percent) and 202 staff (90.18 percent) as effective survey participants. The results revealed that patient resistance mainly stems from a lack of personal experiences with visiting general practice (GP) and being educated or having lived overseas; while staff resistance came from occupation, education, GP training certificate, and knowledge and experience with specialists. Living in overseas and knowledge of GP concepts, gender and education are associated with resistance of accepting the new practice model for both patients and staff. ORIGINALITY/VALUE: There are few Chinese studies on process reengineering in the medical sector; this is the first study to adopt this medical consultation model and change in patients' consultation culture in Mainland China. Applying organizational change and process reengineering theories to medical and healthcare services not only extends and expands hospital management theory but also allows investigation of modern hospital management practice. The experience from this study can serve as a reference to promote this new consultation model in Chinese healthcare reform.


Assuntos
Medicina Geral/organização & administração , Inovação Organizacional , Pacientes/psicologia , Recursos Humanos em Hospital/psicologia , Adolescente , Adulto , Idoso , China , Eficiência Organizacional , Feminino , Reforma dos Serviços de Saúde/organização & administração , Humanos , Masculino , Pessoa de Meia-Idade , Estudos de Casos Organizacionais , Atenção Primária à Saúde/organização & administração , Opinião Pública , Especialização , Confiança , Adulto Jovem
20.
Biochem Biophys Res Commun ; 503(1): 86-93, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29852177

RESUMO

Cervical cancer is the second commonest cancer among women in the worldwide, and the majority cause of death in various countries, highlighting the importance of investigating new therapeutic targets. Rh family, C glycoprotein (RHCG) belongs to the Rhesus (Rh) family and was first identified as Rh blood group antigens. It has been confirmed to function in cancer progression, including prostate cancer and esophageal squamous cell carcinoma. However, its role in cervical cancer has never been explored. The present study indicated that RHCG was down-regulated in cervical cancers compared to that in normal cervical tissues, and further decreased in cervical cancer cell lines. Functionally, RHCG overexpression reduced cervical cancer cell proliferation and migration, as evidenced by the decreased transforming growth factor (TGF)-ß1, matrix metalloproteinase (MMP)-2 and MMP-9 expressions in cancer cells; however, an opposite effect was observed when RHCG was knocked down. Further, increase of RHCG markedly induced apoptosis in cervical cancer cells by improving the cleavage of Caspase-3 and poly (ADP-Ribose) polymerase (PARP). And cells transfected with RHCG siRNA exhibited a notable reduction of cleaved Caspase-3 and PARP. Moreover, nucleus nuclear factor-κB (NF-κB) and whole cell xIPA expressions were markedly reduced by over-expressing RHCG. Conversely, suppressing RHCG elevated NF-κB activation and xIPA expression in cervical cancer cells. Notably, we found that TGF-ß1 treatment could abolish the effects of RHCG over-expression on the reduction of cell migration and enhancement of apoptosis in cervical cancer cells. Over-expressing RHCG-reduced NF-κB activation and xIPA expression were also abrogated by TGF-ß1 pre-treatment. Additionally, enhancing NF-κB activity could restore xIPA expressions and decrease apoptotic response in cervical cancer cells over-expressing RHCG. In vivo, we also found that RHCG over-expression reduced cervical tumor growth through the same signaling pathways as we found in vitro. Therefore, RHCG may be a potential prognostic biomarker and therapeutic target for human cervical cancer.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Glicoproteínas de Membrana/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Neoplasias do Colo do Útero/prevenção & controle , Animais , Apoptose/fisiologia , Caspase 3/metabolismo , Proteínas de Transporte de Cátions/antagonistas & inibidores , Proteínas de Transporte de Cátions/genética , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Progressão da Doença , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Células HeLa , Xenoenxertos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
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