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1.
Int J Med Microbiol ; 315: 151621, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38759506

RESUMEN

Preterm infants face a high risk of various complications, and their gut microbiota plays a pivotal role in health. Delivery modes have been reported to affect the development of gut microbiota in term infants, but its impact on preterm infants remains unclear. Here, we collected fecal samples from 30 preterm infants at five-time points within the first four weeks of life. Employing 16 S rRNA sequencing, principal coordinates analysis, the analysis of similarities, and the Wilcoxon rank-sum test, we examined the top dominant phyla and genera, the temporal changes in specific taxa abundance, and their relationship with delivery modes, such as Escherichia-Shigella and Enterococcus based on vaginal delivery and Pluralibacter related to cesarean section. Moreover, we identified particular bacteria, such as Taonella, Patulibacter, and others, whose proportions fluctuated among preterm infants born via different delivery modes at varying time points, as well as the microbiota types and functions. These results indicated the influence of delivery mode on the composition and function of the preterm infant gut microbiota. Importantly, these effects are time-dependent during the early stages of life. These insights shed light on the pivotal role of delivery mode in shaping the gut microbiota of preterm infants and have significant clinical implications for their care and management.


Asunto(s)
Bacterias , Parto Obstétrico , Heces , Microbioma Gastrointestinal , Recien Nacido Prematuro , ARN Ribosómico 16S , Humanos , Recién Nacido , Heces/microbiología , Femenino , ARN Ribosómico 16S/genética , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Masculino , Embarazo , Cesárea
2.
Int J Mol Sci ; 23(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36012643

RESUMEN

The gastrointestinal tract constantly communicates with the environment, receiving and processing a wide range of information. The contents of the gastrointestinal tract and the gastrointestinal tract generate mechanical and chemical signals, which are essential for regulating digestive function and feeding behavior. There are many receptors here that sense intestinal contents, including nutrients, microbes, hormones, and small molecule compounds. In signal transduction, ion channels are indispensable as an essential component that can generate intracellular ionic changes or electrical signals. Ion channels generate electrical activity in numerous neurons and, more importantly, alter the action of non-neurons simply and effectively, and also affect satiety, molecular secretion, intestinal secretion, and motility through mechanisms of peripheral sensation, signaling, and altered cellular function. In this review, we focus on the identity of ion channels in chemosensing and mechanosensing in the gastrointestinal tract.


Asunto(s)
Canales Iónicos , Mecanotransducción Celular , Conducta Alimentaria , Tracto Gastrointestinal/metabolismo , Canales Iónicos/metabolismo , Iones , Mecanotransducción Celular/fisiología , Transducción de Señal
3.
Artículo en Inglés | MEDLINE | ID: mdl-33645455

RESUMEN

The focus of this research was on the catalytic reduction of nitrate to nitrogen gas for the water conservation. Zero-valent iron (Fe0) with bimetallic catalyst that carrier supported palladium (Pd) and copper (Cu) was innovatively applied in this study. First, XPS (X-ray photoelectron spectroscopy) analyses and experiments were conducted to study the mechanism of the catalytic reduction of nitrate. In the catalytic reaction, which is regarded as a stepwise process, Fe0 was the electron provider; Pd and Cu supported on carrier played indispensable but distinct roles. The kinetics suggested that the process was better reflected by first-order kinetics of the Langmuir-Hinshelwood model. Additionally, first-order kinetics of the catalytic reaction under the effect of catalysts with different carriers (SiO2, silica gel, kaolin, diatomite, γ-Al2O3, graphene) were further studied. Pd-Cu/graphene catalyst showed higher catalytic performance compared with other catalysts.


Asunto(s)
Cobre/química , Desnitrificación , Hierro/química , Paladio/química , Catálisis , Grafito/química , Cinética , Nitratos/química , Nitratos/aislamiento & purificación , Nitrógeno/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(1): 252-6, 2014 Jan.
Artículo en Zh | MEDLINE | ID: mdl-24783571

RESUMEN

Applying Monte Carlo method, the present paper simulates the emitted X-ray spectrum of miniature X-ray tube with thirteen thickness of beryllium window in the range from 50 to 500 microm. By analyzing the characteristic of the spectrums, the reasonable choice of thickness of beryllium window relies on the application and for the beryllium window it is not the thinner the better. Taking in-situ EDXRF as an example, though the emission X-ray intensity is higher as the thickness of the beryllium window becomes thinner, the proportion of useless low-energy X-ray (<5 keV) intensity to all energy X-ray intensity also is higher (>20%). The accuracy of in-situ EDXRF will be reduced when the high-throughput low-energy X-ray enters the detector. Therefore, this paper puts forward several parameters as judgment index for beryllium window thickness, which is described as follows: 1)The intensity ratios of the K-series X-ray to middle-energy (5-25 keV) bremsstrahlung and middle-high-energy (5-50 keV) bremsstrahlung (F1 and F3); 2)The intensity ratios of useless low-energy X-ray (<5 keV) to middle-energy (5-25 keV) X-ray and middle-high-energy (5-50 keV) X-ray (F2 and F4), it can reflect the relative intensity of useless low-energy X-ray. The simulation results demonstrate that with the increase in the beryllium window thickness, the value of F1 (F3) improves slowly, and the value of F2 (F4) decreases rapidly. In addition to the judgment index discussed above, and considering the X-ray shielded by beryllium window, the beryllium window of miniature X-ray tube can be determined. Based on simulation analysis, the thickness of around 250 microm is appropriate to miniature X-ray tube applied in the in-situ EDXRF. Comparing the emitted spectrum with 50 microm-thick beryllium window, 71.66% of low-energy X-rays are shielded, only 21.31% of X-rays with energy from 5 to 50 keV is shielded, the intensity ratio of low-energy X-ray to total energy X-ray is less than 10%, and the intensity proportion of K-series X-ray to middle-high energy X-ray maintains a high level. In other words, when the mobile X-ray source with 250 microm beryllium window is used in the in-situ EDXRF, proportion of effective signal is higher, and effect of energy resolution of the detection is least; Moreover, the relative intensity of the excitation spectral scattering background, which is obtained by detection for specimen excitation analysis, will remain at low level, thus to ensure the precision of the result of element analysis. For the beryllium window in the application of radiation therapy, the thicker the better. At this time, low-energy X-ray flux maintains a high level, and it can ensure that radiation dose is concentrated on treatment tissue.

5.
Sci Rep ; 13(1): 7670, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37169847

RESUMEN

We assessed dynamic changes in visceral hypersensitivity and fecal metabolomics through a mouse model of irritable bowel syndrome (IBS) from childhood to adulthood. A mouse model of IBS was constructed with maternal separation (MS) in early life. Male mice aged 25, 40, and 70 days were used. Visceral sensitivity was assessed by recording the reaction between the abdominal withdrawal reflex and colorectal distension. Metabolomics was identified and quantified by liquid chromatography-tandem mass spectrometry. The visceral sensitivity of the MS group was significantly higher than that of the non-separation (NS) group in the three age groups. The top four fecal differential metabolites in the different age groups were lipids, lipid molecules, organic heterocyclic compounds, organic acids and derivatives, and benzenoids. Five identical differential metabolites were detected in the feces and ileal contents of the MS and NS groups at different ages, namely, benzamide, taurine, acetyl-L-carnitine, indole, and ethylbenzene. Taurine and hypotaurine metabolism were the most relevant pathways at P25, whereas histidine metabolism was the most relevant pathway at P40 and P70. Visceral hypersensitivity in the MS group lasted from childhood to adulthood. The different metabolites and metabolic pathways detected in MS groups of different ages provide a theoretical basis for IBS pathogenesis.


Asunto(s)
Síndrome del Colon Irritable , Niño , Masculino , Humanos , Ratones , Animales , Síndrome del Colon Irritable/metabolismo , Privación Materna , Heces/química , Metabolómica , Reflejo
6.
Infect Drug Resist ; 16: 5473-5483, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37638073

RESUMEN

Objective: To examine the association between the fecal microbiota of acute diarrhea in children and provide gut microbiota information related the acute diarrhea with rotavirus. Patients and Methods: Children with acute diarrhea aged 3-60 months were selected for the study. Routine stool examination was performed, and stool samples were collected and stored at -80 °C until further analysis. Fecal microbial DNA was extracted, and DNA concentration and quality were detected. PCR amplification and 16S rDNA high-throughput sequencing analysis using the Illumina MiSeq platform were performed, and intestinal flora was statistically analyzed. Results: Children with acute diarrhea exhibited gut microbial dysbiosis. Lower microbial diversity and richness were observed in the viral enteritis and bacterial enteritis groups than in the control group. Composition of the microbiota in acute diarrhea differed from that in the control group. The Bacteroidetes/Firmicutes dramatically decreased in the viral enteritis and bacterial enteritis groups. However, the relative abundance of Proteobacteria and Fusobacteria increased, especially in the bacterial enteritis group. In addition, the relative abundance of Actinobacteria had dramatically increased in the viral enteritis group. According to the Kyoto Encyclopedia of Genes and Genomes map analysis, the membrane transport dysfunction was caused by rotavirus infection, while the membrane transport dysfunction was more evident in bacterial infection. Conclusion: Acute diarrhea infections cause fecal microbiota dysbiosis in children. Changes in fecal microflora in children suggest that the regulation of intestinal flora in children with acute diarrhea should be strengthened.

7.
Heliyon ; 9(6): e16437, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37260904

RESUMEN

Background & aims: Approximately 5%-10% of the population in most geographical regions suffer from irritable bowel syndrome (IBS), which creates a significant burden on individual patients, their families, and society. Recent advances in IBS therapies have indicated that vitamin D supplementation is potential to relieve its symptoms, but evidence of this is lacking. This meta-analysis aimed to estimate the effect of vitamin D on gastrointestinal (GI) symptoms in IBS patients. Methods: The PubMed, Embase, and Cochrane Central Register of Controlled Trials databases were searched from their inception to March 2022. Statistical analyses were performed with Stata 12.0 and Review Manager 5.4, and statistical significance was defined as P < 0.05. The pooled results are presented as weighted mean differences (WMD) and 95% confidence intervals (CI). Results: The meta-analysis including 6 randomized controlled trials (RCT) with 572 patients found a significant difference in IBS symptom severity score (WMD, -34.88; 95% CI, -62.48 to -7.27; P = 0.013; random-effects model) but no significant difference in IBS quality of life score (WMD, 3.33; 95% CI, -5.12 to -11.77; P = 0.440; random-effects model). Conclusions: Overall, IBS patients may benefit from vitamin D supplementation to reduce the GI symptoms.

8.
Nutrients ; 15(5)2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36904154

RESUMEN

(1) Background: Irritable bowel syndrome (IBS) is a global public health problem, the pathogenesis of which has not been fully explored. Limiting fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) can relieve symptoms in some patients with IBS. Studies have shown that normal microcirculation perfusion is necessary to maintain the primary function of the gastrointestinal system. Here, we hypothesized that IBS pathogenesis might be related to abnormalities in colonic microcirculation. A low-FODMAP diet could alleviate visceral hypersensitivity (VH) by improving colonic microcirculation; (2) Methods: C57BL/6 mice were raised to establish an IBS-like rodent model using water avoidance (WA) stress or SHAM-WA as a control, one hour per day for ten days. The mice in the WA group were administered different levels of the FODMAP diet: 2.1% regular FODMAP (WA-RF), 10% high FODMAP diet (WA-HF), 5% medium FODMAP diet (WA-MF), and 0% low FODMAP diet (WA-LF) for the following 14 days. The body weight and food consumption of the mice were recorded. Visceral sensitivity was measured as colorectal distention (CRD) using the abdominal withdrawal reflex (AWR) score. Colonic microcirculation was assessed using laser speckle contrast imaging (LCSI). Vascular endothelial-derived growth factor (VEGF) was detected using immunofluorescence staining; (3) Results: The threshold values of CRD pressure in the WA-RF, WA-HF, and WA-MF groups were significantly lower than those in the SHAM-WA group. Moreover, we observed that colonic microcirculation perfusion decreased, and the expression of VEGF protein increased in these three groups of mice. Interestingly, a low-FODMAP dietary intervention could reverse this situation. Specifically, a low-FODMAP diet increased colonic microcirculation perfusion, reduced VEGF protein expression in mice, and increased the threshold of VH. There was a significant positive correlation between colonic microcirculation and threshold for VH; (4) Conclusions: These results demonstrate that a low-FODMAP diet can alter VH by affecting colonic microcirculation. Changes in intestinal microcirculation may be related to VEGF expression.


Asunto(s)
Disacáridos , Síndrome del Colon Irritable , Ratones , Animales , Monosacáridos , Agua , Dieta FODMAP , Microcirculación , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ratones Endogámicos C57BL , Fermentación , Oligosacáridos , Dieta/métodos , Dieta Baja en Carbohidratos/métodos
9.
Front Endocrinol (Lausanne) ; 14: 1193556, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38027192

RESUMEN

In the gastrointestinal tract, serotonin (5-hydroxytryptamine, 5-HT) is an important monoamine that regulates intestinal dynamics. QGP-1 cells are human-derived enterochromaffin cells that secrete 5-HT and functionally express Piezo ion channels associated with cellular mechanosensation. Piezo ion channels can be blocked by Grammostola spatulata mechanotoxin 4 (GsMTx4), a spider venom peptide that inhibits cationic mechanosensitive channels. The primary aim of this study was to explore the effects of GsMTx4 on 5-HT secretion in QGP-1 cells in vitro. We investigated the transcript and protein levels of the Piezo1/2 ion channel, tryptophan hydroxylase 1 (TPH1), and mitogen-activated protein kinase signaling pathways. In addition, we observed that GsMTx4 affected mouse intestinal motility in vivo. Furthermore, GsMTx4 blocked the response of QGP-1 cells to ultrasound, a mechanical stimulus.The prolonged presence of GsMTx4 increased the 5-HT levels in the QGP-1 cell culture system, whereas Piezo1/2 expression decreased, and TPH1 expression increased. This effect was accompanied by the increased phosphorylation of the p38 protein. GsMTx4 increased the entire intestinal passage time of carmine without altering intestinal inflammation. Taken together, inhibition of Piezo1/2 can mediate an increase in 5-HT, which is associated with TPH1, a key enzyme for 5-HT synthesis. It is also accompanied by the activation of the p38 signaling pathway. Inhibitors of Piezo1/2 can modulate 5-HT secretion and influence intestinal motility.


Asunto(s)
Células Enterocromafines , Canales Iónicos , Serotonina , Animales , Humanos , Ratones , Células Enterocromafines/metabolismo , Intestinos/metabolismo , Intestinos/fisiología , Canales Iónicos/genética , Canales Iónicos/metabolismo , Serotonina/farmacología , Serotonina/metabolismo , Transducción de Señal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiología
10.
Front Chem ; 11: 1130563, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36936526

RESUMEN

Mechanosensitive channel of large conductance (MscL) is the most thoroughly studied mechanosensitive channel in prokaryotes. Owing to its small molecular weight, clear mechanical gating mechanism, and nanopore forming ability upon opening, accumulating studies are implemented in regulating cell function by activating mechanosensitive channel of large conductance in mammalian cells. This study aimed to investigate the potentials of mechanosensitive channel of large conductance as a nanomedicine and a mechano-inducer in non-small cell lung cancer (NSCLC) A549 cells from the view of molecular pathways and acoustics. The stable cytoplasmic vacuolization model about NSCLC A549 cells was established via the targeted expression of modified mechanosensitive channel of large conductance channels in different subcellular organelles. Subsequent morphological changes in cellular component and expression levels of cell death markers are analyzed by confocal imaging and western blots. The permeability of mitochondrial inner membrane (MIM) exhibited a vital role in cytoplasmic vacuolization formation. Furthermore, mechanosensitive channel of large conductance channel can be activated by low intensity focused ultrasound (LIFU) in A549 cells, and the suppression of A549 tumors in vivo was achieved by LIFU with sound pressure as low as 0.053 MPa. These findings provide insights into the mechanisms underlying non-apoptotic cell death, and validate the nanochannel-based non-invasive ultrasonic strategy for cancer therapy.

11.
Front Microbiol ; 14: 1255525, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37849921

RESUMEN

Background: Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorder. Traditionally, early life stress (ELS) is predisposed to IBS in adult. However, whether ELS induces IBS in early life remains unclear. Methods: Separated cohort studies were conducted in neonatal male pups of C57BL/6 mice by maternal separation (MS) model. MS and non-separation mice were scheduled to be evaluated for prime IBS-phenotypes, including visceral hypersensitivity, intestinal motility, intestinal permeability, and anxiety-like behavior. Ileal contents and fecal samples were collected and analyzed by 16S rRNA gene sequencing and bacterial community analyses. Subcellular structures of intestinal epithelial, such as epithelial tight junctions and mitochondria, were observed under transmission electron microscopy. Results: MS induced visceral hypersensitivity and decreased total intestinal transit time from childhood to adulthood. In addition, MS induced intestinal hyperpermeability and anxiety-like behavior from adolescence to adulthood. Besides, MS affected intestinal microbial composition from childhood to adulthood. Moreover, MS disrupted intestinal mitochondrial structure from childhood to adulthood. Conclusion: The study showed for the first time that MS induced IBS from early life to adulthood in mice. The disrupted intestinal mitochondrial structure and the significant dysbiosis of intestinal microbiota in early life may contribute to the initiation and progress of IBS from early life to adulthood.

12.
J Pediatr (Rio J) ; 98(5): 526-532, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35240047

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the serum Syndecan-1 (SDC-1) levels in patients with immunoglobulin-A vasculitis (IgAV) in children and its relation with gastrointestinal involvements. METHODS: Sixty-eight children with IgAV and 48 healthy children were enrolled in this cross-sectional study. Clinical and related laboratory data were collected from a computerized hospital database. Serum SDC-1 was collected on admission prior to treatment. RESULTS: Forty-eight patients fully met the IgAV diagnostic criteria at admission (IgAV group), 20 patients with rash only and diagnosed IgAV during hospitalization (Purpura group). In IgAV group, 30 patients with gastrointestinal involvements (IgAV-GI group) and 18 patients without gastrointestinal involvements (IgAV-NGI group). SDC-1 serum levels were significantly higher in the IgAV group (86.37 ng/mL (IQR 59.16-117.14 ng/mL)) than in the controls (20.37 ng/mL (IQR 15.52-26.45 ng/mL)) and the Purpura group (32.66 ng/mL (IQR 14.87-49.89 ng/mL)). Additionally, SDC-1 (OR = 1.08) was independently associated with IgAV with a cut-off value (sensitivity and specificity) of 66.55 ng/mL (68.8%, 95.0%), and the area under the curve was 0.908. The serum SDC-1 levels of the IgAV-GI group (106.92 ± 50.12 ng/mL) were significantly higher than those in the IgAV-NGI group (67.52 ± 17.59 ng/mL). Logistic regression analysis showed that SDC-1 (OR = 1.03) was independently associated with IgAV-GI with a cut-off value of 89.39 ng/mL. CONCLUSIONS: SDC-1 serum levels may mirror vascular endothelium injury and mucosal damage in IgAV. Its applicability as a surrogate biomarker in IgAV remains to be determined.


Asunto(s)
Vasculitis por IgA , Sindecano-1 , Biomarcadores , Niño , Estudios Transversales , Humanos , Inmunoglobulina A
13.
Front Cell Neurosci ; 16: 837166, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35370559

RESUMEN

Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorders, also known as disorders of the gut-brain interaction; however, the pathophysiology of IBS remains unclear. Early life stress (ELS) is one of the most common risk factors for IBS development. However, the molecular mechanisms by which ELS induces IBS remain unclear. Enterochromaffin cells (ECs), as a prime source of peripheral serotonin (5-HT), play a pivotal role in intestinal motility, secretion, proinflammatory and anti-inflammatory effects, and visceral sensation. ECs can sense various stimuli and microbiota metabolites such as short-chain fatty acids (SCFAs) and secondary bile acids. ECs can sense the luminal environment and transmit signals to the brain via exogenous vagal and spinal nerve afferents. Increasing evidence suggests that an ECs-5-HT signaling imbalance plays a crucial role in the pathogenesis of ELS-induced IBS. A recent study using a maternal separation (MS) animal model mimicking ELS showed that MS induced expansion of intestinal stem cells and their differentiation toward secretory lineages, including ECs, leading to ECs hyperplasia, increased 5-HT production, and visceral hyperalgesia. This suggests that ELS-induced IBS may be associated with increased ECs-5-HT signaling. Furthermore, ECs are closely related to corticotropin-releasing hormone, mast cells, neuron growth factor, bile acids, and SCFAs, all of which contribute to the pathogenesis of IBS. Collectively, ECs may play a role in the pathogenesis of ELS-induced IBS. Therefore, this review summarizes the physiological function of ECs and focuses on their potential role in the pathogenesis of IBS based on clinical and pre-clinical evidence.

14.
Front Microbiol ; 13: 853184, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35547124

RESUMEN

Background: Helicobacter pylori (H. pylori) infection is the main cause of chronic gastritis and duodenal ulcer in children. Little is known about the effect of H. pylori on gastric microbiota in children with duodenal ulcer. This study is aimed at the characteristics of gastric microbiota in children with duodenal ulcer on H. pylori infection. Methods: We studied 23 children diagnosed with duodenal ulcer by gastric endoscopy because of the gastrointestinal symptoms, 15 children were diagnosed with H. pylori infection, while 8 children were without H. pylori infection. Endoscopic mucosal biopsy samples were obtained for DNA extraction. Microbiomes were analyzed by 16S rRNA profiling and microbial functions were predicted using the software Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt). Results: Bacterial richness and diversity of gastric microbiota in duodenal ulcer with H. pylori-positive were lower than those negative. The gastric microbiota in H. pylori-positive group significantly reduced proportions of six phyla and fifteen genera; only Helicobacter taxa were more abundant in H. pylori-positive group. Co-expression network analysis showed a more complex network of interactions in the H. pylori-positive group than that in the H. pylori-negative group. For the predicted functions, lower abundance in the pathways of carbohydrate metabolism, signal transduction, amino acid metabolism, and lipid metabolism were found in H. pylori-positive group than the H. pylori-negative group. H. pylori colonization reduces a microbial community with genotoxic potential in the gastric mucosa of children with duodenal ulcer. Conclusions: The presence of H. pylori significantly influences gastric microbiota and results in a lower abundance of multiple taxonomic levels in children with duodenal ulcer. Children with duodenal ulcer exhibit a dysbiotic microbial community with genotoxic potential, which is distinct from that of children with H. pylori infection. Clinical Trial Registration: [http://www.chictr.org.cn], identifier [ChiCTR1800015190].

15.
Sci Rep ; 11(1): 22374, 2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34789761

RESUMEN

We created 3D-reduced graphene oxide/sodium alginate double network (GAD) beads to address the problem of local water pollution by antimony. GAD is a novel material with the high specific surface area of graphene and biosecurity of sodium alginate. Due to the introduction of graphene, the thermal stability and specific surface area of GAD are enhanced, as shown from the FTIR, TGA, BET, Raman, and XRD characterizations. The influence of different environmental variables-such as the pH, dosage, temperature, contact time, and sodium chloride concentration on the Sb(III) sorption with GAD-was investigated. The adsorption results fit well with both the pseudo-second order (R2 > 0.99) and Freundlich (R2 > 0.99) isotherm models. The temperature rise has a negative influence on the adsorption. The Langmuir adsorption capacity is 7.67 mg/g, which is higher than many adsorbents. The GAD results from the fixed-bed adsorption experiment were a good fit with the Thomas model (R2 > 0.99). In addition, GAD appears to be a renewable and ideal adsorbent for the treatment of antimony pollution in aqueous systems.

16.
J Nanosci Nanotechnol ; 21(9): 4846-4851, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691876

RESUMEN

Birnessite-MnO2 nanoflakes were synthesized via an aqueous oxidation method at 90 °C using Mn(CH3COO)2, NaOH, and KMnO4. The samples' morphology, crystalline structure, and optical property were determined by field emission scanning electron microscopy, X-ray powder diffraction and UV-Vis spectrophotometry. The birnessite-MnO2 nanoflakes were converted to KxMn8O16 and Mn suboxides following a decrease in the concentration of KMnO4 in the reaction. The amount of NaOH in the reaction determined the type of precursor. Without NaOH, the precursor was converted from Mn(OH)2 to Mn2+ (from Mn(CH3COO)2), thereby enabling the synthesis of birnessite-MnO2 nanoflowers. The formation mechanism of birnessite-MnO2 nanoflowers and nanoflakes was clarified via the corresponding simulated crystal structures. Evaluation of the synthesized samples confirmed that the birnessite-MnO2 nanoflakes and nanoflowers exhibited excellent degradation properties.


Asunto(s)
Compuestos de Manganeso , Óxidos , Oxidación-Reducción , Difracción de Rayos X
17.
BMC Cancer ; 10: 184, 2010 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-20459642

RESUMEN

BACKGROUND: Insulin-like growth factor-I receptor (IGFIR) has been shown to regulate the tumor development. The objective of the current study is to determine the association of IGFIR with lymph node metastasis and to explore the related mechanism in human colorectal cancer in clinic. METHODS: In a random series of 98 colorectal cancer patients, the expressions of IGFIR, vascular endothelial growth factor (VEGF) and VEGF-C were investigated by immunohistochemistry, and the association of these expressions with lymph node metastasis was statistically analyzed. The expressions of VEGF and VEGF-C in colorectal cancer cells stimulated with IGF-I were also examined by real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: Higher rates of IGFIR (46%), VEGF (53%), and VEGF-C (46%) expression were found in colorectal cancer tissues than in normal and colorectal adenoma tissues. These expressions were significantly associated with clinicopathologic factors and lymph node status. We also found the concomitant high expressions of IGFIR/VEGF (P < 0.001) and IGFIR/VEGF-C (P = 0.001) had a stronger correlation with lymph node metastasis than did each alone or both low expressions. In addition, IGF-I could effectively induce the VEGF and VEGF-C mRNA expression and protein secretion in colorectal cancer cells expressing IGFIR molecules. Moreover, Patients who had strong staining for IGFIR, VEGF and VEGF-C showed significantly less favorable survival rates compared with patients who had low staining for these molecules (P < 0.001). The survival rates of patients who were both high expression of IGFIR/VEGF and IGFIR/VEGF-C also were significantly lower compared with patients who were negative or one of high expression of these molecules (P < 0.001). CONCLUSIONS: Together the findings indicated for the first time that simultaneous examination of the expressions of IGFIR, VEGF and VEGF-C will benefit the diagnosis of lymph node metastasis in order to assay the prognosis and determine the treatment strategy in patients with colorectal cancer undergoing surgery.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Receptor IGF Tipo 1/biosíntesis , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Factor C de Crecimiento Endotelial Vascular/biosíntesis , Humanos , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Metástasis Linfática
18.
Cancer Biother Radiopharm ; 35(5): 387-396, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32315535

RESUMEN

Background: Hepatocellular carcinoma (HCC) is an aggressive primary hepatic cancer with high malignancy and poor prognosis. Long noncoding RNA HOTAIR has been classified as an oncogene to accelerate cell proliferation, migration, and invasion in many cancer types by interacting with the miRNA. Therefore, we assumed that HOTAIR might participate in HCC cell progression by interacting with miR-217-5p expression. Materials and Methods: The expression of HOTAIR and miR-217-5p in 35 HCC patients and HCC cells was measured by quantitative real-time polymerase chain reaction. Cell transfection was conducted using Lipofectamine 2000 transfection reagent. CCK8 and flow cytometry was applied for the measurement of cell proliferation and apoptosis. Cell migration and invasion capacities were carried out by transwell assay. Xenograft mice were constructed by subcutaneously injecting of stably transfected Huh-7 cells in mice. The interaction between HOTAIR and miR-217-5p was determined by luciferase reporter system. Protein expression of P13K, p-P13K, AKT, p-AKT, MMP-2, and MMP-9 was analyzed using Western blot assay. Results: The expression of HOTAIR was upregulated, whereas miR-217-5p was downregulated in HCC tumor tissues and cell lines (Hep3B and Huh-7) compared with normal tissues and human normal liver cell line MIHA. In addition, HOTAIR expression was negatively correlated with miR-217-5p expression in HCC (r2 = 0.1867, p = 0.0171). More importantly, HOTAIR knockdown induced apoptosis and inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). In vivo experiments revealed that the interference of HOTAIR inhibited tumor growth. Subsequently, luciferase reporter system confirmed the interaction between HOTAIR and miR-217-5p. The rescue experiments clarified that miR-217-5p inhibitor attenuated the suppression of HOTAIR silencing on HCC cell proliferation, migration, invasion, and EMT. Furthermore, miR-217-5p inhibitor restored the inhibition of HOTAIR silencing mediated p-PI3K/p-AKT/MMP-2/9 protein expression. Conclusions: HOTAIR contributes to cell progression in HCC by sponging miR-217-5p, representing promising biomarkers for HCC treatment.


Asunto(s)
Carcinoma Hepatocelular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Apoptosis/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal/genética , Técnicas de Silenciamiento del Gen , Hepatectomía , Humanos , Hígado/patología , Hígado/cirugía , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Ratones , Invasividad Neoplásica/genética , ARN Largo no Codificante/genética , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Int J Biol Macromol ; 147: 898-910, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31726158

RESUMEN

Graphene oxide/alginate hydrogel membranes (GAHMs) were prepared by cross-linking a casting solution (blending graphene oxide, sodium alginate and urea) with a calcium chloride solution. The adsorption performance and mechanism for the removel of Cr(III) and Pb(II) were investigated. The GAHMs, before and after adsorption, were characterized by FT-IR, SEM, EDX and XPS, and their hydrophilicity was determined. The kinetics, isotherm and thermodynamics models were introduced. Results indicated that the optimal pH for the membranes removing Cr(III) and Pb(II) was 6.0 and 5.0 respectively. The adsorption capacity for both metal ions was positively correlated with the initial concentration and contact time and their adsorption was consistent with the pseudo-second-order kinetic model. The Langmuir isotherm better described the adsorption equilibrium. Moreover, the Langmuir model showed that the maximum adsorption capacity for Pb(II) was better than that for Cr(III) (327.9 and 118.6 mg/g, respectively). Thermodynamics analysis showed that the adsorption for Cr(III) by GAHMs was endothermic, whereas that of Pb(II) was exothermic. After five adsorption-desorption cycles, a high adsorption efficiency for both metal ions was maintained. This novel membrane material (GAHMs) is potentially an effective membrane adsorbent for the removal of Cr(III) and Pb(II) ions in practical applications.


Asunto(s)
Alginatos/química , Cromo/química , Grafito/química , Hidrogeles/química , Plomo/química , Membranas Artificiales , Contaminantes Químicos del Agua/química , Purificación del Agua , Adsorción , Termodinámica
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