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1.
Biochem Genet ; 62(2): 1379-1395, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37610692

RESUMO

Circular RNAs (circRNAs) are reported to be involved in the tumorigenesis of lung adenocarcinoma (LUAD). Here, this study focused on studying the function and mechanism of circHSPB6 in LUAD progression. Levels of genes and proteins were tested using qRT-PCR and western blotting analyses. The 5-ethynyl-2'-deoxyuridine (EdU), colony formation, flow cytometry, and transwell assays were adopted for in vitro assays. In vivo assay was conducted using mouse xenograft models. The binding between let-7a-2-3p and circHSPB6 or CCL2 was validated using RIP and dual-luciferase reporter assays. The M2 polarization of tumor-associated macrophages (TAMs) was analyzed by flow cytometry. LUAD tissues and cells showed high circHSPB6 expression, knockdown of circHSPB6-suppressed LUAD cell proliferation, migration, invasion, and induced cell apoptosis in vitro, as well as hindered tumor growth in vivo. Mechanistically, circHSPB6/let-7a-2-3p/CCL2 forms a feedback loop. CircHSPB6 could regulate CCL2 expression via sponging let-7a-2-3p. Further rescue assays showed that the effects of circHSPB6 silencing on LUAD cells were reversed by let-7a-2-3p inhibition or CCL2 overexpression. Moreover, circHSPB6 promoted the M2 polarization and infiltration of TAMs by CCL2. Functionally, circHSPB6 knockdown in A549 and H1299 cells inhibited TAM M2 polarization and then suppressed cell proliferation, migration, invasion, and emergency medical technicians (EMT) progression, while these effects were reversed by CCL2 up-regulation CircHSPB6 induced TAM M2 polarization to promote LUAD cell proliferation, migration, invasion, and EMT progression through let-7a-2-3p/CCL2 axis.

2.
Neuromodulation ; 27(2): 382-391, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38127047

RESUMO

OBJECTIVES: Nearly half of patients with slow transit constipation (STC) are not completely satisfied with their traditional remedies. We aimed to evaluate the therapeutic value and possible involved mechanism of transcutaneous electrical acustimulation (TEA) at ST36 in patients with STC. MATERIALS AND METHODS: Seventy patients with STC were randomly divided into TEA (n = 35) and sham-TEA (n = 35) to undergo a two-week treatment with TEA at ST36 or sham point. After the two-week treatment, 18 patients from each group randomly underwent a few physiological tests, including the electrocardiogram (ECG), anorectal manometry, colon transit test, and blood drawing. After a two-week washout period, TEA was performed in both groups for two weeks. RESULTS: Spontaneous bowel movements per week were increased, and scores of constipation symptoms were decreased, after a two-week blind TEA but not sham-TEA, which were sustained after a two-week washout period. Improvement in quality of life and psychologic states also was observed with blind TEA treatment. Mechanistically, the two-week blind TEA accelerated colon transit assessed by barium strip excretion rate (the effect was sustained after a two-week washout period), enhanced vagal nerve activity evaluated by the spectral analysis of heart rate variability derived from the ECG, and decreased circulating vasoactive intestinal peptide. CONCLUSIONS: Noninvasive TEA relieves constipation and improves quality of life and psychologic states in patients with STC, and the effects are sustained for ≥two weeks. The therapeutic effects of TEA may be attributed to the acceleration of colon transit and decrease of vasoactive intestinal peptide mediated through the vagal mechanism.


Assuntos
Qualidade de Vida , Estimulação Elétrica Nervosa Transcutânea , Humanos , Peptídeo Intestinal Vasoativo , Trânsito Gastrointestinal/fisiologia , Constipação Intestinal/terapia , Colo
3.
Anal Chem ; 95(48): 17903-17911, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-37972093

RESUMO

In this work, the aggregation-induced emission ligand 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene (H4TCBPE) was rigidified in the Ti-O network to form novel electrochemiluminescence (ECL) emitter H4TCBPE-TiO2 nanospheres, which acted as an effective ECL emitter to construct an "on-off" ECL biosensor for ultrasensitive detection of malathion (Mal). H4TCBPE-TiO2 exhibited excellent ECL responses due to the Ti-O network that can restrict the intramolecular free motions within H4TCBPE and then reduce the nonradiative relaxation. Moreover, TiO2 can act as an ECL co-reaction accelerator to promote the generation of sulfate radical anion (SO4•-), which interacts with H4TCBPE in the Ti-O network to produce enhanced ECL response. In the presence of Mal, numerous ligated probes (probe 1 to probe 2, P1-P2) were formed and released by copper-free click nucleic acid ligation reaction, which then hybridized with hairpin probe 1 (H1)-modified H4TCBPE-TiO2-based electrode surface. The P1-P2 probes can initiate the target-assisted terminal deoxynucleoside transferase (TdTase) extended reaction to produce long tails of deoxyadenine with abundant biotin, which can load numerous streptavidin-functionalized ferrocenedicarboxylic acid polymer (SA-PFc), causing quenching of the ECL signal. Thus, the ultrasensitive ECL biosensor based on H4TCBPE-TiO2 ECL emitter and click chemistry-actuated TdTase amplification strategy presents a desirable range from 0.001 to 100 ng/mL and a detection limit low to 9.9 fg/mL. Overall, this work has paved an avenue for the development of novel ECL emitters, which has opened up new prospects for ECL biosensing.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes , Titânio
4.
Br J Nutr ; : 1-13, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37132123

RESUMO

Menaquinone-7 (MK-7), a multipotent vitamin K2, possesses a wide range of biological activities, a precise curative effect and excellent safety. A simple and rapid LC-APCI-MS/MS method for the determination of MK-7 in human plasma with single liquid-liquid extraction (LLE) extraction and 4·5-min analysis time has been developed and validated. Four per cent bovine serum albumin (BSA) was used as surrogate matrix for standard curves and endogenous baseline subtraction. This method was reproducible and reliable and was used to analyse of MK-7 in human plasma. The endogenous circadian rhythm and bioavailability of MK-7 were investigated in two randomised single-dose, open, one-way clinical trials (Study I and Study II). A total of five healthy male subjects were enrolled in Study I and 12 healthy male subjects in Study II. Single-dose (1 mg) of MK-7 was given to each subject under fasting condition, and all eligible subjects were given a restricting VK2 diet for 4 d prior to drug administration and during the trial. The experiment results of Study I demonstrated that endogenous MK-7 has no circadian rhythm in individuals. Both studies showed MK-7 are absorbed with peak plasma concentrations at about 6 h after intake and has a very long half-life time.

5.
Mikrochim Acta ; 190(10): 382, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37697070

RESUMO

In the developed assay, multiorbital 3D DNA walker (MO DNA walker) was applied as signal amplified protocol for enhancing the detection signal of the photothermal biosensor, which was designed for sensitive detection of miRNA based on the H2S triggered conversation of photothermal reagent. When the target molecule is present, the DNA walking strand was released and then hybridize with track strands. The landing of walking particles (WPT) on the tracking particles (TPT) promotes the relative movement of the WPT around TPT, thus releasing large amount of horseradish peroxidase (HRP) with the aid of DNAzyme. After reacting with Na2S2O3 and H2O2, multiple H2S can be generated in situ based on the catalytic ability of HRP. Meanwhile, cubic Prussian blue (CPB) was synthesized and exhibited superior photothermal response, which can be served as efficient photothermal reagent and H2S responsive acceptor. Significantly, the photothermal signal of CPB could be obviously reduced after challenged with H2S ascribed to synchronous reaction between the ferric ion (Fe3+) and H2S. The improved walking area and freedom enable significant signal amplification, enhancing the biosensor's performance. Under ideal circumstances, the proposed photothermal assay demonstrated excellent performance for determination of miRNA-21.


Assuntos
DNA Catalítico , MicroRNAs , Peróxido de Hidrogênio , DNA , Peroxidase do Rábano Silvestre
6.
J Cell Biochem ; 123(11): 1857-1872, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36037317

RESUMO

Cholangiocyte death accompanied by the progression of primary biliary cholangitis (PBC) has not yet been thoroughly investigated. Thus, we are aimed to explore the role of HSP90 and a potential treatment strategy in cholangiocyte necroptosis. First, we detected the expression of HSP90 and necroptotic markers in liver tissues from patients and mice with PBC by immunohistochemistry (IHC) and real-time polymerase chain reaction (PCR). Then, the HSP90 inhibitor, 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), was administered by intraperitoneal injection to evaluate its therapeutic effect for PBC by IHC, real-time PCR, and western blotting. Human intrahepatic bile duct epithelial cells (HIBECs) were induced to necroptosis by toxic bile acid and lipopolysaccharide (LPS) treatment, and evaluated via Cell Counting Kit-8 and flow cytometry assays. Additionally, 17-DMAG, cycloheximide, and a proteasome inhibitor were used to evaluate the role of HSP90 in cholangiocyte necroptosis. We found that the expression of HSP90 was elevated in the cholangiocytes of patients and mice with PBC, along with higher expressions of receptor-interacting serine/threonine-protein kinase 1 (RIPK1), RIPK3, mixed lineage kinase domain-like protein (MLKL), and phosphorylated-MLKL (p-MLKL). Proinflammatory cytokines and antibody levels of the E2 subunit of pyruvate dehydrogenase complex decreased after treatment with 17-DMAG in PBC mice. Meanwhile, RIPK1, RIPK3, phosphorylated-RIPK3, MLKL, and p-MLKL protein expressions decreased with 17-DMAG treatment. In vitro, 17-DMAG and necrostatin-1 prevented glycochenodeoxycholic acid and LPS-induced necroptosis of HIBECs. Immunoprecipitation and high-performance liquid chromatography-mass spectrometry analysis showed that RIPK1 combined with HSP90. Additionally, the 17-DMAG treatment reduced the RIPK1 half-life. Overall, 17-DMAG might be a potential therapeutic agent for PBC via cholangiocyte necroptosis prevention by accelerating RIPK1 degradation.


Assuntos
Cirrose Hepática Biliar , Necroptose , Humanos , Animais , Camundongos , Lipopolissacarídeos/toxicidade , Proteínas Quinases/metabolismo , Proteínas de Choque Térmico HSP90 , Células Epiteliais/metabolismo
7.
BMC Biol ; 19(1): 236, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732185

RESUMO

BACKGROUND: Dopamine (DA) is a neurotransmitter that plays roles in movement, cognition, attention, and reward responses, and deficient DA signaling is associated with the progression of a number of neurological diseases, such as Parkinson's disease. Due to its critical functions, DA expression levels in the brain are tightly controlled, with one important and rate-limiting step in its biosynthetic pathway being catalyzed by tyrosine hydroxylase (TH), an enzyme that uses iron ion (Fe2+) as a cofactor. A role for metal ions has additionally been associated with the etiology of Parkinson's disease. However, the way dopamine synthesis is regulated in vivo or whether regulation of metal ion levels is a component of DA synthesis is not fully understood. Here, we analyze the role of Catsup, the Drosophila ortholog of the mammalian zinc transporter SLC39A7 (ZIP7), in regulating dopamine levels. RESULTS: We found that Catsup is a functional zinc transporter that regulates intracellular zinc distribution between the ER/Golgi and the cytosol. Loss-of-function of Catsup leads to increased DA levels, and we showed that the increased dopamine production is due to a reduction in zinc levels in the cytosol. Zinc ion (Zn2+) negatively regulates dopamine synthesis through direct inhibition of TH activity, by antagonizing Fe2+ binding to TH, thus rendering the enzyme ineffective or non-functional. CONCLUSIONS: Our findings uncovered a previously unknown mechanism underlying the control of cellular dopamine expression, with normal levels of dopamine synthesis being maintained through a balance between Fe2+ and Zn2+ ions. The findings also provide support for metal modulation as a possible therapeutic strategy in the treatment of Parkinson's disease and other dopamine-related diseases.


Assuntos
Proteínas de Transporte de Cátions , Dopamina , Drosophila melanogaster , Animais , Proteínas de Transporte de Cátions/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Retículo Endoplasmático/metabolismo , Ferro , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo , Zinco
8.
Nano Lett ; 21(2): 914-920, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33400545

RESUMO

Materials with a zero refractive index support electromagnetic modes that exhibit stationary phase profiles. While such materials have been realized across the visible and near-infrared spectral range, radiative and dissipative optical losses have hindered their development. We reduce losses in zero-index, on-chip photonic crystals by introducing high-Q resonances via resonance-trapped and symmetry-protected states. Using these approaches, we experimentally obtain quality factors of 2.6 × 103 and 7.8 × 103 at near-infrared wavelengths, corresponding to an order-of-magnitude reduction in propagation loss over previous designs. Our work presents a viable approach to fabricate zero-index on-chip nanophotonic devices with low-loss.

9.
J Gastroenterol Hepatol ; 36(2): 455-466, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32667711

RESUMO

BACKGROUND AND AIM: 5-Lipoxygenase has been reported to enhance cell proliferation, migration, and invasion. Epithelial-mesenchymal transition is considered an important process for tumor metastasis and invasion. METHODS: The 5-lipoxygenase expression levels and the prognoses in patients with gastric cancer were evaluated by immunohistochemistry and by the log-rank test on Kaplan-Meier curves. We established 5-lipoxygenase-overexpressed and 5-lipoxygenase-silenced gastric cancer cells and measured migration, invasion, and epithelial-mesenchymal transition makers to examine the role of 5-lipoxygenase in gastric cancer in vitro. In vivo, 5-lipoxygenase-overexpressed gastric cancer cells were administered into mice by subcutaneous injection, intraperitoneal injection or splenic intravenous injection to study the proliferation or metastasis of 5-lipoxygenase in mice. Using the extracellular signal-regulated kinase pathway inhibitor U0126 and activator tumor growth factor-ß, we investigated the mechanism of epithelial-mesenchymal transition induced by 5-lipoxygenase in gastric cancer cells. RESULTS: 5-Lipoxygenase was upregulated in gastric cancer tissues and was related to poor overall survival in gastric cancer patients. 5-Lipoxygenase promoted gastric cancer cell proliferation, migration, and invasion and induced the process of epithelial-mesenchymal transition in gastric cancer cells. In the nude mouse model, mice with gastric cancer tumors overexpressing 5-LOX had a faster tumor growth rate and more severe abdominal and liver metastases than the control group. Inhibition of extracellular signal-regulated kinase signaling by U0126 or activation by tumor growth factor-ß neutralized the effect of 5-LOX overexpression or silencing on epithelial-mesenchymal transition. CONCLUSION: 5-Lipoxygenase promotes epithelial-mesenchymal transition in gastric cancer by activating the extracellular signal-regulated kinase signaling pathway.


Assuntos
Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/fisiologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Araquidonato 5-Lipoxigenase/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica/genética , Neoplasias Gástricas/metabolismo
10.
Med Sci Monit ; 27: e927619, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33536405

RESUMO

BACKGROUND The diagnostic efficacy of endoscopic ultrasound (EUS) elastography for alimentary tract diseases remains uncertain. The aim of this study was to evaluate the utility of EUS elastography in differential diagnosis between the 2 most common subepithelium tumors of the digestive tract - gastrointestinal stromal tumors (GISTs) and gastrointestinal leiomyomas (GILs) - which cannot be differentiated by conventional EUS imaging. MATERIAL AND METHODS Electronic records were retrospectively reviewed from Jan 2015 to Jul 2019. Patients accepting EUS elastography with histopathological diagnosis of GISTs or GILs were included. The images of EUS elastography were analyzed by hue histogram in Photoshop. Hue values of RGB, R, G, and B channels of each group were acquired. We used the t test, ROC curve analysis, and binary logistic regression analysis for data post-processing. RESULTS We included 47 patients with GISTs and 14 with GILs. The mean±standard deviations (SD) of hue values were 20.25±0.72, -0.79±0.78, 20.79±1.68, 39.72±1.30 for GISTs and 20.80±0.46, 1.80±1.05, 28.39±2.15, and 31.95±2.60 for GILs of RGB, R, G, and B channels, respectively. The t test showed statistically significant differences in mean hue values between GISTs and GILs in B and G channels, but not in RGB and R channels. The area under the ROC curve combining B and G values was 0.723. Binary logistic regression analysis suggested no statistically significant difference in ability to differentiate between GISTs and GILs with B and G values (P>0.05). CONCLUSIONS There was insufficient evidence to support the application of quantitative EUS elastography for differential diagnosis of GISTs and GILs in this study.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Idoso , Diagnóstico Diferencial , Endoscopia Gastrointestinal/métodos , Endossonografia/métodos , Feminino , Trato Gastrointestinal/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos
11.
BMC Med Imaging ; 21(1): 133, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530768

RESUMO

BACKGROUND: To compare the changes in quantitative parameters and the size and degree of 18F-fluorodeoxyglucose ([18F]FDG) uptake of malignant tumor lesions between Bayesian penalized-likelihood (BPL) and non-BPL reconstruction algorithms. METHODS: Positron emission tomography/computed tomography images of 86 malignant tumor lesions were reconstructed using the algorithms of ordered subset expectation maximization (OSEM), OSEM + time of flight (TOF), OSEM + TOF + point spread function (PSF), and BPL. [18F]FDG parameters of maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and signal-to-background ratio (SBR) of these lesions were measured. Quantitative parameters between the different reconstruction algorithms were compared, and correlations between parameter variation and lesion size or the degree of [18F]FDG uptake were analyzed. RESULTS: After BPL reconstruction, SUVmax, SUVmean, and SBR were significantly increased, MTV was significantly decreased. The difference values of %ΔSUVmax, %ΔSUVmean, %ΔSBR, and the absolute value of %ΔMTV between BPL and OSEM + TOF were 40.00%, 38.50%, 33.60%, and 33.20%, respectively, which were significantly higher than those between BPL and OSEM + TOF + PSF. Similar results were observed in the comparison of OSEM and OSEM + TOF + PSF with BPL. The %ΔSUVmax, %ΔSUVmean, and %ΔSBR were all significantly negatively correlated with the size and degree of [18F]FDG uptake in the lesions, whereas significant positive correlations were observed for %ΔMTV and %ΔTLG. CONCLUSION: The BPL reconstruction algorithm significantly increased SUVmax, SUVmean, and SBR and decreased MTV of tumor lesions, especially in small or relatively hypometabolic lesions.


Assuntos
Algoritmos , Fluordesoxiglucose F18/farmacocinética , Processamento de Imagem Assistida por Computador/métodos , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Sensibilidade e Especificidade
12.
J Biol Inorg Chem ; 24(2): 151-169, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30564887

RESUMO

Three iridium(III) polypyridyl complexes [Ir(ppy)2(PYTA)](PF6) (1) (ppy = 2-phenylpyridine), [Ir(bzq)2(PYTA)](PF6) (2) (bzq = benzo[h]quinolone) and [Ir(piq)2(PYTA)](PF6) (3) (piq = 1-phenylisoquinoline, PYTA = 2,4-diamino-6-(2'-pyridyl)-1,3,5-triazine) were synthesized and characterized by elemental analysis, IR, 1H NMR and 13C NMR. The cytotoxic activity of the complexes toward cancer SGC-7901, Eca-109, A549, HeLa, HepG2, BEL-7402 and normal LO2 cell lines was investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Complex 3 shows the most effective on inhibiting the above cell growth among these complexes. The complexes locate at the lysosomes and mitochondria. AO/EB, Annex V and PI and comet assays indicate that the complexes can induce apoptosis in SGC-7901 cells. Intracellular ROS and mitochondrial membrane potential were examined under fluorescence microscopy. The results demonstrate that the complexes increase the intracellular ROS levels and induce a decrease in the mitochondrial membrane potential. The complexes can enhance intracellular Ca2+ concentration and cause a release of cytochrome c. The autophagy was studied using MDC staining and western blot. Complexes 1-3 can effectively inhibit the cell invasion with a concentration-dependent manner. Additionally, the complexes target tubules and inhibit the polymerization of tubules. The antimicrobial activity of the complexes against S. aureus, E. coli, Salmonella and L. monocytogenes was explored. The mechanism shows that the complexes induce apoptosis in SGC-7901 cells through ROS-mediated lysosomal-mitochondrial, targeting tubules and damage DNA pathways. Three iridium(III) complexes [Ir(N-C)2(PYTA)](PF6) (N-C = ppy, 1; bzq, 2; piq, 3) were synthesized and characterized. The anticancer activity of the complexes against SGC-7901 cells was studied by apoptosis, comet assay, autophagy, ROS, mitochondrial membrane potential, intracellular Ca2+ levels, release of cytochrome c, tubules and western blot analysis. The antibacterial activity in vitro was also assayed.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Irídio/farmacologia , Fenazopiridina/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli/efeitos dos fármacos , Humanos , Irídio/química , Listeria monocytogenes/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenazopiridina/química , Salmonella/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
13.
Ecotoxicol Environ Saf ; 186: 109791, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31627094

RESUMO

Uptake, translocation and speciation of As in rice plants have been investigated through hydroponic cultivations under stress from different As species. After germination, rice seedlings were treated with arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid (MMA) or dimethylarsinic acid (DMA) at concentrations of 50, 100, 150, 200 and 250 µg/L for 24 days. Only inorganic As species were detected in the rice plants treated with As(III) or As(V), indicating that rice seedlings could not methylate inorganic As in hydroponic culture. As(V) in the rice roots was readily reduced to As(III) after uptake; thus, As(III) was the dominant species in the rice roots (>60%) and shoots (>80%) regardless of As(III) or As(V) treatment. The increased As(III) proportion in the nutrient solutions was due to the efflux of As(III) from the rice roots. MMA with relatively low stability in the blank nutrient solution was demethylated to As(III). Moreover, demethylation and methylation of MMA might occur simultaneously in rice plants. Specific proportions of MMA and AsB were observed in the rice roots treated with DMA, implying that MMA and AsB were the DMA metabolites in rice roots after detoxification.


Assuntos
Arsenicais/química , Arsenicais/farmacologia , Oryza/efeitos dos fármacos , Oryza/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Arsenicais/metabolismo , Transporte Biológico , Hidroponia , Metilação , Oxirredução , Raízes de Plantas/metabolismo , Plântula/metabolismo
14.
Molecules ; 24(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466318

RESUMO

Three iridium(III) complexes ([Ir(Hppy)2(L)](PF6) (Hppy = 2-phenylpyridine, L = 5-nitrophenanthroline, NP), 1; 5-nitro-6-amino-phenanthroline (NAP), 2; and 5,6-diamino-phenanthroline (DAP) 3 were synthesized and characterized. The cytotoxicities of Ir(III) complexes 1-3 against cancer cell lines SGC-7901, A549, HeLa, Eca-109, HepG2, BEL-7402, and normal NIH 3T3 cells were investigated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT) method. The results showed that the three iridium(III) complexes had moderate in vitro anti-tumor activity toward SGC-7901 cells with IC50 values of 3.6 ± 0.1 µM for 1, 14.1 ± 0.5 µM for 2, and 11.1 ± 1.3 µM for 3. Further studies showed that 1-3 induce cell apoptosis/death through DNA damage, cell cycle arrest at the S or G0/G1 phase, ROS elevation, increased levels of Ca2+, high mitochondrial membrane depolarization, and cellular ATP depletion. Transwell and Colony-Forming assays revealed that complexes 1-3 can also effectively inhibit the metastasis and proliferation of tumor cells. These results demonstrate that 1-3 induce apoptosis in SGC-7901 cells through ROS-mediated mitochondrial damage and DNA damage pathways, as well as by inhibiting cell invasion, thereby exerting anti-tumor cell proliferation activity in vitro.


Assuntos
Complexos de Coordenação/síntese química , Irídio/química , Piridinas/química , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Gástricas/metabolismo , Células A549 , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Células Hep G2 , Humanos , Concentração Inibidora 50 , Camundongos , Células NIH 3T3 , Neoplasias Gástricas/tratamento farmacológico
15.
Clin Infect Dis ; 64(9): 1244-1250, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28207070

RESUMO

Background: Giardiasis, the most common enteric parasitic infection in the United States, causes an estimated 1.2 million episodes of illness annually. Published clinical recommendations include readily available Giardia-specific diagnostic testing and antiparasitic drugs. We investigated sequences of giardiasis diagnostic and treatment events using MarketScan, a large health insurance claims database. Methods: We created a longitudinal cohort of 2995 persons diagnosed with giardiasis (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 007.1) from 2006 to 2010, and analyzed claims occurring 90 days before to 90 days after initial diagnosis. We evaluated differences in number and sequence of visits, diagnostic tests, and prescriptions by age group (children 1-17 years, adults 18-64 years) using χ2 tests and data visualization software. Results: Among 2995 patients (212433 claims), 18% had a Giardia-specific test followed by or concurrent with an effective antiparasitic drug, without ineffective antibiotics. Almost two-thirds of patients had an antiparasitic and 27% had an antibiotic during the study window. Compared with children, adults more often had ≥3 visits before diagnosis (19% vs 15%; P = .02). Adults were also less likely to have a Giardia-specific diagnostic test (48% vs 58%; P < .001) and more likely to have an antibiotic prescription (28% vs 25%; P = .04). When Giardia-specific tests and antiparasitic and antibiotic prescriptions were examined, pediatric clinical event sequences most frequently began with a Giardia-specific test, whereas adult sequences most frequently began with an antiparasitic prescription. Conclusions: Giardiasis care infrequently follows all aspects of clinical recommendations. Multiple differences between pediatric and adult care, despite age-agnostic recommendations, suggest opportunities for provider education or tailored guidance.


Assuntos
Antiparasitários/uso terapêutico , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Gerenciamento Clínico , Uso de Medicamentos , Giardíase/diagnóstico , Giardíase/tratamento farmacológico , Demandas Administrativas em Assistência à Saúde/estatística & dados numéricos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Fidelidade a Diretrizes , Humanos , Lactente , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
16.
Am J Physiol Regul Integr Comp Physiol ; 309(2): R109-18, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25972459

RESUMO

Background electroacupuncture (EA) at acupoint ST-36 (Zusanli) has been used to alleviate gastrointestinal symptoms and improve gastrointestinal motility, but the effects and mechanisms of EA on enteric nervous system (ENS) have scarcely been investigated. SD rats were randomly divided into eight groups: normal control group, diabetes mellitus group (DM), chronic high-frequency EA (C-HEA), chronic low-frequency EA (C-LEA), chronic sham stimulation group (C-SEA), acute high-frequency EA group (A-HEA), acute low-frequency EA group (A-LEA), and diabetic with acute sham stimulation group (A-SEA). The parameters of HEA included a frequency of 100 Hz and an amplitude of 1 mA, while the parameters for LEA were 10 Hz and 1 mA. The expressions of PGP9.5, neuronal nitric oxide synthase neurons, CHAT neurons, glia cell line-derived neurotrophic factor (GDNF) and p-Akt were measured by immunofluorescence or immunohistochemistry, real-time PCR, and Western blotting methods in colon tissues of each rat. The total neurons and the two types of enteric neurons (neuronal nitric oxide synthase and choline acetyl transferase neurons), together with GDNF and p-Akt in the mRNA and protein level were significantly decreased in DM group compared with the normal control group in colon (P < 0.01). Compared with DM or all other DM with EA groups, the chronic HEA could induce a more significant quantitative increase in the mRNA and protein level of the enteric neurons and GDNF and p-Akt in colon (P < 0.01). EA with high-frequency and long-term stimuli at acupoint ST-36 can induce regeneration of lost enteric neurons in diabetic rats, and GDNF and PI3K/Akt signal pathway may play an important role in EA-induced regeneration of impaired enteric neurons.


Assuntos
Pontos de Acupuntura , Colo/inervação , Diabetes Mellitus Experimental/terapia , Eletroacupuntura/métodos , Sistema Nervoso Entérico/enzimologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Regeneração Nervosa , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Colina O-Acetiltransferase/metabolismo , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatologia , Sistema Nervoso Entérico/fisiopatologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Masculino , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
17.
Mol Biol Rep ; 42(3): 569-80, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25344111

RESUMO

Low temperature is a major environmental constraint on the production of apples worldwide. An apple rootstock with high cold tolerance was selected to identify genes related to stress tolerance. The transcriptional profiles of the genes in the leaves were examined after various intervals of exposure to cold stress. We obtained three libraries of 14,219, 11,176 and 16,116 tag-mapped predicted coding sequences at three time points (0, 1 and 6 h) during cold stress. In the two time periods, which were from 0 to 1 h and from 1 to 6 h, 139 and 1,085 genes were upregulated, and 1,499 and 381 genes were downregulated, respectively. These groups included a large number of unknown genes. The distribution of genes indicated cold adaptation in the plant. Most of the differential expression genes (DEGs) had temporal specificity and significantly different expression changes at different time points. The classification of DEGs by GO category and KEGG pathway analysis revealed that the DEGs are involved in numerous biological pathways, including metabolism, plant-pathogen interaction and signal transduction. Eleven randomly selected tag-mapped genes were examined by qRT-PCR. The results of the qRT-PCR were in accordance with the transcriptional profiles. The most upregulated gene (MDP0000198054) from 0 to 1 h encodes a dehydration-responsive element-binding protein/C-repeat factor (DREB/CBF). In this study, MDP0000198054 and related genes involved in the cold stress response were discussed. These results could provide new insights into the stress tolerance mechanisms of apple rootstocks.


Assuntos
Resposta ao Choque Frio/genética , Regulação da Expressão Gênica de Plantas , Malus/genética , Adaptação Biológica/genética , Temperatura Baixa , Biologia Computacional , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Reprodutibilidade dos Testes
18.
Chirality ; 27(9): 598-604, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26096573

RESUMO

Much attention has been paid to chiral ionic liquids (ILs) in analytical chemistry, especially its application in capillary electrophoresis (CE) enantioseparation. However, the investigation of chiral ionic liquids synergistic systems based on antibiotic chiral selectors has been reported in only one article. In this work, a novel chiral ionic liquid, tetramethylammonium-L-hydroxyproline (TMA-L-Hyp), was applied for the first time in CE chiral separation to evaluate its potential synergistic effect with clindamycin phosphate (CP) as the chiral selector. As observed, significantly improved separation was obtained in this TMA-L-Hyp/CP synergistic system compared to TMA-L-Hyp or a CP single system. Several primary factors that might influence the separation were investigated, including CP concentration, TMA-L-Hyp concentration, buffer pH, types and concentrations of organic modifier, applied voltage, and capillary temperature. The best results were obtained with a 40 mM borax buffer (pH 7.6) containing 30 mM TMA-L-Hyp, 80 mM CP, and 20% (v/v) methanol, while the applied voltage and temperature were set at 20 kV and 20°C, respectively.


Assuntos
Clindamicina/análogos & derivados , Eletroforese Capilar/métodos , Hidroxiprolina/química , Líquidos Iônicos/química , Compostos de Amônio Quaternário/química , Soluções Tampão , Clindamicina/química , Eletricidade , Concentração de Íons de Hidrogênio , Estereoisomerismo , Temperatura
19.
Biochem Biophys Res Commun ; 445(2): 394-7, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24525118

RESUMO

Tubby-like proteins (TLPs) are found in a broad range of multicellular organisms. In mammals, genetic mutation of tubby or other TLPs can result in certain disease phenotypes related to animal specific characters: obesity, retinal degeneration, hearing loss, et al. Plants also harbor a large number of TLP genes, but the information in plants is far more limited. We identified a highly up-regulated obesity-like gene, MdTLP7, in our previous study of apple differential gene expression profile under chilling, indicating its possible role in plant abiotic stress tolerance. cDNA of MdTLP7 was amplified and expressed in Escherichia coli. In the solid and solution medium, the rate of growth and the quantity of the cell carrying MdTLP7 gene were significantly more than that of empty vector under salt and temperature stresses. To identify the functional region, serial deletion from both N-terminus and C-terminus of MdTLP7 was performed. In 415 amino acid polypeptide chain of MdTLP7, a middle conservative fragment (120-310 amino acid residues) played vital roles in stress tolerance. This fragment was involved in ß barrel of Tubby domain according to the model of Tubby domain. All above results suggested MdTLP7 confers stress-tolerance to E. coli cell against abiotic stresses.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Malus/genética , Proteínas de Plantas/genética , Adaptação Fisiológica , Sequência de Aminoácidos , Escherichia coli/fisiologia , Expressão Gênica , Genes de Plantas , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Plantas/química , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alinhamento de Sequência , Estresse Fisiológico
20.
Sci Total Environ ; 919: 170890, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346657

RESUMO

Soil is the world's largest terrestrial carbon pool and plays an important role in the global carbon cycle, which may be greatly affected by global change. Recently, research frameworks have indicated that division of soil organic carbon (SOC) into two forms particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) can help us better understand SOC cycle. However, there is a lack of the use of meta-analysis combined with machine learning models to explore the spatial distribution of SOC fractions at large scales. Based on 356 studies conducted in Chinese terrestrial ecosystems, we performed a meta-analysis of extracted data and measured data combined with machine learning models to reveal the spatial distribution of soil POC density (POCD) and MAOC density (MAOCD) and the main drivers of variations in POCD and MAOCD. Our study demonstrated that POCD and MAOCD in China's soil were 3.24 and 2.61 kg m-2, with stocks of 31.10 and 25.06 Pg, respectively. Climate, soil, and vegetation properties together explained 44.9 % and 27.2 % of the variation in POCD and MAOCD, respectively. Climate was more important than other variables in controlling the changes in POCD, with mean annual temperature being specifically the main driver. Soil, however, was more important than other variables in controlling changes in MAOCD, with soil clay content being the main driver. Compared to the other climate scenarios, the rate of change in POCD and MAOCD was higher with a 1.5 °C increase in temperature. In the future, we should pay more attention to the impact of climate change on POCD, which provides a theoretical basis for achieving the "dual-carbon" target. Our study contributes to the understanding of the potential mechanisms of the changes in SOC fractions under global change and provides useful information for future prediction models to simulate the impacts of global change.

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