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1.
Life (Basel) ; 14(5)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38792616

RESUMEN

Soil salinization poses a threat to the sustainability of agricultural production and has become a global issue. Cotton is an important cash crop and plays an important role in economic development. Salt stress has been harming the yield and quality of many crops, including cotton, for many years. In recent years, soil salinization has been increasing. It is crucial to study the mechanism of cotton salt tolerance and explore diversified materials and methods to alleviate the salt stress of cotton for the development of the cotton industry. Nanoparticles (NPs) are an effective means to alleviate salt stress. In this study, zinc oxide NPs (ZnO NPs) were sprayed on cotton leaves with the aim of investigating the intrinsic mechanism of NPs to alleviate salt stress in cotton. The results show that the foliar spraying of ZnO NPs significantly alleviated the negative effects of salt stress on hydroponic cotton seedlings, including the improvement of above-ground and root dry and fresh weight, leaf area, seedling height, and stem diameter. In addition, ZnO NPs can significantly improve the salt-induced oxidative stress by reducing the levels of MDA, H2O2, and O2- and increasing the activities of major antioxidant enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Furthermore, RNA-seq showed that the foliar spraying of ZnO NPs could induce the expressions of CNGC, NHX2, AHA3, HAK17, and other genes, and reduce the expression of SKOR, combined with the CBL-CIPK pathway, which alleviated the toxic effect of excessive Na+ and reduced the loss of excessive K+ so that the Na+/K+ ratio was stabilized. In summary, our results indicate that the foliar application of ZnO NPs can alleviate high salt stress in cotton by adjusting the Na+/K+ ratio and regulating antioxidative ability. This provides a new strategy for alleviating the salt stress of cotton and other crops, which is conducive to the development of agriculture.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37006725

RESUMEN

The number and diversity of chemical contaminants in aquatic environments require versatile technologies for their removal. Here we fabricated various electrospun nanofiber mats (ENMs) and tested their ability to sorb six neonicotinoid insecticides, a model family of small, polar contaminants. ENM formulations were polyacrylonitrile (PAN) or carbon nanofibers (CNF; carbonized from PAN), with additives including carbon nanotubes (CNTs; with and without surface carboxyl groups), the cationic surfactant tetrabutyl ammonium bromide (TBAB), and/or phthalic acid (PTA; a CNF porogen). While sorption on pure PAN ENMs was low [equilibrium partition coefficients (K ENM-W ) from 0.9 to 1.2 log units (L/kg)], inclusion of CNTs and/or TBAB generally increased uptake in an additive fashion, with carboxylated CNT composites outperforming non-functionalized CNT analogs. CNF ENMs exhibited as much as a tenfold increase relative to PAN for neonicotinoid sorption, which increased with carbonization temperature. Ultimately, the optimal ENM (CNFs with carboxylated-CNTs, PTA, and carbonized at 800 °C) exhibited relatively fast uptake (equilibrium < 1 day without mixing) and surface-area-normalized capacities comparable to other carbonaceous sorbents (e.g., activated carbon). Collectively, this work demonstrates the versatility of electrospinning to produce novel sorbents specifically designed to target emerging chemical classes for applications including water treatment and passive sampling.

3.
World J Gastrointest Surg ; 15(2): 201-210, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36896307

RESUMEN

BACKGROUND: In China, as the population grows older, the number of elderly people who have died from respiratory problems has increased. AIM: To investigate whether enhanced recovery after surgery (ERAS)-based respiratory function training may help older patients who had abdominal surgery suffer fewer pulmonary problems, shorter hospital stays, and improved lung function. METHODS: The data of 231 elderly individuals having abdominal surgery was retrospectively analyzed. Based on whether ERAS-based respiratory function training was provided, patients were divided into ERAS group (n = 112) and control group (n = 119). Deep vein thrombosis (DVT), pulmonary embolism (PE), and respiratory tract infection (RTI) were the primary outcome variables. Secondary outcome variables included the Borg score Scale, FEV1/FVC and postoperative hospital stay. RESULTS: The percentage of 18.75% of ERAS group participants and 34.45% of control group participants, respectively, had respiratory infections (P = 0.007). None of the individuals experienced PE or DVT. The ERAS group's median postoperative hospital stay was 9.5 d (3-21 d) whereas the control groups was 11 d (4-18 d) (P = 0.028). The Borg score decreased on the 4th d following surgery in the ERAS group compared to the 2nd d prior (P = 0.003). The incidence of RTIs was greater in the control group than in the ERAS group among patients who spent more than 2 d in the hospital before surgery (P = 0.029). CONCLUSION: ERAS-based respiratory function training may reduce the risk of pulmonary complications in older individuals undergoing abdominal surgery.

4.
Front Mol Biosci ; 9: 960457, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36339710

RESUMEN

Background: Although current immunotherapies have achieved some successes for hepatocellular carcinoma (HCC) patients, their benefits are limited for most HCC patients. Therefore, the identification of biomarkers for promoting immunotherapeutic responses in HCC is urgently needed. Methods: Using the TCGA HCC cohort, we investigated correlations of various molecular features with antitumor immune signatures (CD8+ T cell infiltration and cytolytic activity) and an immunosuppressive signature (PD-L1 expression) in HCC. These molecular features included mRNAs, microRNAs (miRNAs), long non-coding RNAs (lncRNAs), proteins, and pathways. Results: We found that the mutations of several oncogenes and tumor suppressor genes significantly correlated with reduced antitumor immune signatures, including TTN, CTNNB1, RB1, ZFHX4, and TP53. It indicates that these genes' mutations may inhibit antitumor immune responses in HCC. Four proteins (Syk, Lck, STAT5, and Caspase-7) had significant positive expression correlations with CD8+ T cell enrichment, cytolytic activity, and PD-L1 expression in HCC. It suggests that these proteins' expression could be useful biomarkers for the response to immune checkpoint inhibitors Similiarly, we identified other types of biomarkers potentially useful for predicting the response to ICIs, including miRNAs (hsa-miR-511-5p, 150-3p, 342-3p, 181a-3p, 625-5p, 4772-3p, 155-3p, 142-5p, 142-3p, 155-5p, 625-3p, 1976, 7702), many lncRNAs, and pathways (apoptosis, cytokine-cytokine receptor interaction, Jak-STAT signaling, MAPK signaling, PI3K-AKT signaling, HIF-1 signaling, ECM receptor interaction, focal adhesion, and estrogen signaling). Further, tumor mutation burden showed no significant correlation with antitumor immunity, while tumor aneuploidy levels showed a significant negative correlation with antitumor immunity. Conclusion: The molecular features significantly associated with HCC immunity could be predictive biomarkers for immunotherapeutic responses in HCC patients. They could also be potential intervention targets for boosting antitumor immunity and immunotherapeutic responses in HCC.

5.
Life Sci ; 310: 121117, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36302497

RESUMEN

AIMS: The "biliary bicarbonate umbrella" is considered a critical protective mechanism of cholangiocytes against bile acid cytotoxicity. Defects in its function are closely related to various chronic cholangiopathies. Carbonic anhydrase 14 (CAR14) is an important element of normal bicarbonate homeostasis and is highly expressed in liver tissues. This study aimed to explore the effects and mechanism of CAR14 on bile acid cytotoxicity in the liver. MAIN METHODS: In vitro, alterations in the whole transcriptome after Car14 gene silencing were assessed by RNA sequencing, and the expression changes in key factors in the "biliary bicarbonate umbrella" were verified by qRT-PCR and western blotting. In vivo, 7 days after bile duct ligation in Car14 gene knockout and wild-type mice, their serum liver function indicators, liver histopathology, hepatic bile acid composition, and whole hepatic proteomic changes were investigated. KEY FINDINGS: In vitro, the transcriptional alterations induced by Car14 silencing were mainly related to transmembrane transport, including ion exchangers and ion channels that are vital in the "biliary bicarbonate umbrella" such as AE2 and CFTR. In vivo, Car14 knockout induced more severe liver dysfunction, hepatic fibrosis and bile duct lesions, and resulted in increased hepatic bile acid levels and altered bile acid compositions in BDL mice. In response, the uptake and synthesis of bile acids in the liver of Car14 knockout mice were suppressed. SIGNIFICANCE: Our data revealed that CAR14 protects the liver against bile acid toxicity, which might provide a theoretical basis for clinical strategies to prevent or treat bile duct diseases.


Asunto(s)
Ácidos y Sales Biliares , Anhidrasas Carbónicas , Ratones , Animales , Ácidos y Sales Biliares/metabolismo , Bicarbonatos/metabolismo , Proteómica , Hígado/metabolismo , Conductos Biliares/metabolismo , Anhidrasas Carbónicas/genética
6.
J Environ Chem Eng ; 10(5)2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36060014

RESUMEN

We previously observed that phosphonate functionalized electrospun nanofibers can uptake U(VI), making them promising materials for sensing and water treatment applications. Here, we investigate the optimal fabrication of these materials and their mechanism of U(VI) binding under the influence of environmentally relevant ions (e.g., Ca2+ and CO 3 2 - ). We found that U(VI) uptake was greatest on polyacrylonitrile (PAN) functionalized with longer-chain phosphonate surfactants (e.g., hexa- and octadecyl phosphonate; HDPA and ODPA, respectively), which were better retained in the nanofiber after surface segregation. Subsequent uptake experiments to better understand specific solid-liquid interfacial interactions were carried out using 5 mg of HDPA-functionalized PAN mats with 10 µM U at pH 6.8 in four systems with different combinations of solutions containing 5 mM calcium (Ca2+) and 5 mM bicarbonate ( HCO 3 - ). U uptake was similar in control solutions containing no Ca2+ and HCO 3 - (resulting in 19 ± 3% U uptake), and in those containing only 5 mM Ca2+ (resulting in 20 ± 3% U uptake). A decrease in U uptake (10 ± 4% U uptake) was observed in experiments with HCO 3 - , indicating that UO2-CO3 complexes may increase uranium solubility. Results from shell-by-shell EXAFS fitting, aqueous extractions, and surface-enhanced Raman scattering (SERS) indicate that U is bound to phosphonate as a monodentate inner sphere surface complex to one of the hydroxyls in the phosphonate functional groups. New knowledge derived from this study on material fabrication and solid-liquid interfacial interactions will help to advance technologies for use in the in-situ detection and treatment of U in water.

7.
Pflugers Arch ; 474(5): 529-539, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35119514

RESUMEN

Carbonic anhydrase XIV (Car14) is highly expressed in the hepatocyte, with predominance in the canalicular membrane and its active site in the extracellular milieu. The aim of this study is to determine the physiological relevance of Car14 for biliary fluid and acid/base output, as well as its role in the maintenance of hepatocellular and cholangiocyte integrity. The common bile duct of anesthetized car14-/- and car14+/+ mice was cannulated and hepatic HCO3- output was measured by microtitration and bile flow gravimetrically before and during stimulation with intravenously applied tauroursodeoxycholic acid (TUDCA). Morphological alterations and hepatic damage were assessed histologically and immunohistochemically in liver tissue from 3- to 52-week-old car14-/- and car14+/+ mice, and gene and/or protein expression was measured for pro-inflammatory cytokines, fibrosis, and cholangiocyte markers. Biliary basal and more so TUDCA-stimulated HCO3- output were significantly reduced in car14-/- mice of all age groups, whereas bile flow and hepatic and ductular morphology were normal at young age. Car14-/- mice developed fibrotic and proliferative changes in the small bile ducts at advanced age, which was accompanied by a reduction in bile flow, and an upregulation of hepatic cytokeratin 19 mRNA and protein expression. Membrane-bound Car14 is essential for biliary HCO3- output, and its loss results in gradual development of small bile duct disease and hepatic fibrosis. Bile flow is not compromised in young adulthood, suggesting that Car14-deficient mice may be a model to study the protective role of biliary canalicular HCO3- against luminal noxi to the cholangiocyte.


Asunto(s)
Bicarbonatos , Conductos Biliares , Animales , Bicarbonatos/metabolismo , Conductos Biliares/metabolismo , Anhidrasas Carbónicas , Proliferación Celular , Hígado/metabolismo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Ratones
8.
Acta Physiol (Oxf) ; 234(3): e13774, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34985202

RESUMEN

AIM: The sodium/hydrogen exchanger 2 (NHE2) is an intestinal acid extruder with crypt-predominant localization and unresolved physiological significance. Our aim was to decipher its role in colonic epithelial cell proliferation, differentiation and electrolyte transport. METHODS: Alterations induced by NHE2-deficiency were addressed in murine nhe2-/- and nhe2+/+ colonic crypts and colonoids, and NHE2-knockdown and control Caco2Bbe cells using pH-fluorometry, gene expression analysis and immunofluorescence. RESULTS: pHi -measurements along the colonic cryptal axis revealed significantly decreased intracellular pH (pHi ) in the middle segment of nhe2-/- compared to nhe2+/+ crypts. Increased Nhe2 mRNA expression was detected in murine colonoids in the transiently amplifying/progenitor cell stage (TA/PE). Lack of Nhe2 altered the differentiation programme of colonic epithelial cells with reduced expression of absorptive lineage markers alkaline phosphatase (iAlp), Slc26a3 and transcription factor hairy and enhancer-of-split 1 (Hes1), but increased expression of secretory lineage markers Mucin 2, trefoil factor 3 (Tff3), enteroendocrine marker chromogranin A and murine atonal homolog 1 (Math1). Enterocyte differentiation was found to be pHi dependent with acidic pHi reducing, and alkaline pHi stimulating the expression of enterocyte differentiation markers in Caco2Bbe cells. A thicker mucus layer, longer crypts and an expanded brush border membrane zone of sodium/hydrogen exchanger 3 (NHE3) abundance may explain the lack of inflammation and the normal fluid absorptive rate in nhe2-/- colon. CONCLUSIONS: The results suggest that NHE2 expression is activated when colonocytes emerge from the stem cell niche. Its activity increases progenitor cell pHi and thereby supports absorptive enterocyte differentiation.


Asunto(s)
Colon , Intercambiadores de Sodio-Hidrógeno , Animales , Linaje de la Célula , Colon/citología , Concentración de Iones de Hidrógeno , Ratones , Microvellosidades/metabolismo , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismo , Transportadores de Sulfato/metabolismo
9.
J Pharm Biomed Anal ; 206: 114349, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34597840

RESUMEN

Chronic hepatitis B (CHB) remains a major public health problem globally. HBeAg seroconversion is a vital hallmark for the improvement of CHB. The plasma metabolic profile has not been clear in CHB patients and searching metabolic candidates to represent HBeAg seroconversion is also difficult currently. In this study, CHB patients were recruited, followed and divided into the HBeAg-positive (HBeAg-pos.) group (n = 29) and the HBeAg-negative (HBeAg-neg.) group (n = 29) based on HBeAg seroconversion or not. The plasma metabolic profiles were measured by gas chromatography-mass spectrometry (GC-MS) at 0 week (0w), 24 weeks (24w) and 48 weeks (48w) after administration. The acquired data was analyzed using orthogonal partial least squares discriminate analysis (OPLS-DA) and the differential metabolites were further assessed by self and group comparison. No differences of age, gender and serological characteristics were observed between two groups at 0w and 48w separately. The OPLS-DA score plots depending on administration time displayed robust metabolic differences no matter HBeAg turned to be negative or not. According to VIP> 1.0, a total of 15 differential metabolites were same in the two groups, 7 differential metabolites (glycolic acid, D-talose, L-proline, L-(-)-arabitol, ethyl-alpha-D-glucopyranoside, L-leucine and dihydroxybutanoic acid) were derived from one group alone and considered as metabolic candidates. At 0w versus (vs.) 24w, only 3 of 7 candidates (L-proline, L-(-)-arabitol, dihydroxybutanoic acid) showed nonuniform in the two groups, while at 0w vs. 48w, all of them varied inconsistently. Conclusively the dynamic metabolic profiles assayed by GC-MS were different between CHB patients with and without HBeAg seroconversion. The 7 metabolic candidates probably had the ability to reflect the CHB progression for HBeAg seroconversion and 3 of them showed strong relationship with HbeAg seroconversion early.


Asunto(s)
Antígenos e de la Hepatitis B , Hepatitis B Crónica , Antivirales/uso terapéutico , Cromatografía de Gases y Espectrometría de Masas , Antígenos e de la Hepatitis B/uso terapéutico , Virus de la Hepatitis B , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/tratamiento farmacológico , Humanos , Interferón-alfa , Metaboloma , Seroconversión , Resultado del Tratamiento
10.
Biotechnol Bioeng ; 118(4): 1587-1596, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33410130

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly throughout the whole world and caused significant difficulties in the prevention and control of the epidemic. In this case, several detection methods have been established based on nucleic acid diagnostic techniques and immunoassays to achieve sensitive and specific detection of SARS-CoV-2. However, most methods are still largely dependent on professional instruments, highly trained operators, and centralized laboratories. These limitations gravely diminish their practicality and portability. Herein, a clustered regularly interspaced short palindromic repeats (CRISPR) Cas12a based assay was developed for portable, rapid and sensitive of SARS-CoV-2. In this assay, samples were quickly pretreated and amplified by reverse transcription recombinase-aided amplification under mild conditions. Then, by combining the CRISPR Cas12a system and a glucose-producing reaction, the signal of the virus was converted to that of glucose, which can be quantitatively read by a personal glucose meter in a few seconds. Nucleocapsid protein gene was tested as a model target, and the sensitivity for quantitative detection was as low as 10 copies/µl, which basically meet the needs of clinical diagnosis. In addition, with the advantages of lower material cost, shorter detection time, and no requirement for professional instrument in comparison with quantitative reverse transcription-polymerase chain reaction, this assay is expected to provide a powerful technical support for the early diagnosis and intervention during epidemic prevention and control.


Asunto(s)
Técnicas Biosensibles , COVID-19/diagnóstico , Sistemas CRISPR-Cas , Glucosa/análisis , SARS-CoV-2/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Prueba de COVID-19 , Humanos , Técnicas de Amplificación de Ácido Nucleico
11.
Int J Oncol ; 57(5): 1157-1168, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33300052

RESUMEN

Colorectal cancer (CRC) is a tumor type characterized by high patient morbidity and mortality. It has been reported that long non­coding (lncRNA) LUNAR1 (LUNAR1) participates in the regulation of tumor progression, such as diffuse large B­cell lymphoma. However, its role and underlying mechanisms in CRC progression have not been elucidated. The present study was designed to investigate the underlying mechanisms by which LUNAR1 regulates CRC progression. RT­qPCR and Pearson's correlation analysis revealed that LUNAR1 was highly expressed and was negatively associated with the overall survival of CRC patients. Moreover, CCK­8, clone formation, wound­healing migration, Transwell chamber and FACs assay analyses showed that LUNAR1 knockdown inhibited CRC cell proliferation, migration and invasion, while accelerating cell apoptosis. Additionally, LUNAR1 was found to function as a sponge of miR­495­3p, which was predicted by TargetScan and confirmed by luciferase reporter assay. Furthermore, functional studies indicated that miR­495­3p overexpression inhibited CRC cell proliferation, migration and invasion, while accelerating cell apoptosis. In addition, bioinformatics and luciferase reporter assays showed that miR­495­3p was found to negatively target Myc binding protein (MYCBP), and functional research showed that LUNAR1 accelerated CRC progression via the miR­495­3p/MYCBP axis. In conclusion, LUNAR1 accelerates CRC progression via the miR­495­3p/MYCBP axis, indicating that LUNAR1 may serve as a prognostic biomarker for CRC patients.


Asunto(s)
Neoplasias Colorrectales/etiología , Proteínas de Unión al ADN/fisiología , MicroARNs/fisiología , ARN Largo no Codificante/fisiología , Factores de Transcripción/fisiología , Adulto , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica
12.
ACS Synth Biol ; 9(11): 3114-3123, 2020 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-33047952

RESUMEN

Existing methods of detecting foreign genes and their expression products from genetically modified organisms (GMOs) suffer from the requirement of professional equipment and skillful operators. The same problem stays for the CRISPR-Cas12a system, although it has been emerging as a powerful tool for nucleic acid detection due to its remarkable sensitivity and specificity. In this report, a portable platform for the visible detection of GMOs based on CRISPR-Cas12a was established, which relies on a color change of gold nanorods (GNRs) caused by the invertase-glucose oxidase cascade reaction and the Fenton reaction for signal readout. A nopaline synthase (NOS) terminator was employed as a model target commonly existing in foreign genes of GMOs. With the help of recombinase-aided amplification, this platform achieved comparable sensitivity of DNA targets (1 aM) with that of a fluorescence reporting assay. As low as 0.1 wt % genetically modified (GM) content in Bt-11 maize was visually observed by unaided eyes, and the semiquantitation of GM ingredients can be obtained within the range of 0.1 to 40 wt % through the absorption measurement of GNRs. Furthermore, five real samples were tested by our method, and the results indicated that the GM ingredient percentages of GMO samples were 2.24 and 24.08 wt %, respectively, while the other three samples were GMO-free. With the advantages of a simple procedure, no need for large or professional instruments, high sensitivity, and selectivity, this platform is expected to provide reasonable technical support for the safe supervision of GMOs.


Asunto(s)
Aminoácido Oxidorreductasas/genética , Proteínas Bacterianas/genética , Proteínas Asociadas a CRISPR/genética , Sistemas CRISPR-Cas/genética , Productos Agrícolas/genética , Endodesoxirribonucleasas/genética , Plantas Modificadas Genéticamente/genética , Regiones Terminadoras Genéticas/genética , Técnicas Biosensibles/métodos , ADN/genética , Cartilla de ADN/genética , Glucosa Oxidasa/genética , Oro/química , Nanotubos/química , Recombinasas/genética
13.
Biochem Pharmacol ; 178: 114040, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32422138

RESUMEN

BACKGROUND: The molecular basis for heat-stable Escherichia coli enterotoxin (STa) action and its synthetic analogue linaclotide is well understood at the enterocyte level. Pharmacologic strategies to prevent STa-induced intestinal fluid loss by inhibiting its effector molecules, however, have achieved insufficient inhibition in vivo. AIMS AND EXPERIMENTAL APPROACH: To investigate whether the currently discussed effector molecules and signaling mechanisms of STa/linaclotide-induced diarrhea have similar relevance in vivo than at the enterocyte level, we studied the effect of 10-7M of the STa analogue linaclotide on short circuit current (Isc) of chambered isolated jejunal mucosa, and on the in vivo action on fluid transport in a perfused segment of proximal jejunum of anesthetized mice. The selected mice were deficient of transport (NHE3, CFTR, Slc26a3/a6), adaptor (NHERF1-3), or signal transduction molecules [cGMP-dependent kinase II (GKII)] considered to be downstream effectors after STa/linaclotide binding to guanylate cyclase C (GCC). Selective NHE3 inhibition by tenapanor was also employed. KEY RESULTS, CONCLUSIONS AND IMPLICATIONS: The comparison allowed the separation of effectors for stimulation of electrogenic anion secretion and for inhibition of electrolyte/fluid absorption in response to STa/linaclotide. The cGKII-NHERF1-CFTR and cGKII-NHERF2-NHE3 interactions are indeed major effectors of small intestinal fluid loss downstream of GCC activation in vitro and in vivo, but 50% of the linaclotide-induced fluid loss in vivo, while dependent on CFTR activation and NHE3 inhibition, does not involve cGKII, and 30% does not depend on NHERF1 or NHERF2. A combined NHERF1 and NHERF2 inhibition appears nevertheless a good pharmacological strategy against STa-mediated fluid loss.


Asunto(s)
Diarrea/inducido químicamente , Diarrea/metabolismo , Agonistas de la Guanilato Ciclasa C/farmacología , Mucosa Intestinal/enzimología , Yeyuno/metabolismo , Proteínas Quinasas/metabolismo , Animales , Células CACO-2 , Agonistas de la Guanilato Ciclasa C/efectos adversos , Humanos , Mucosa Intestinal/efectos de los fármacos , Transporte Iónico/efectos de los fármacos , Transporte Iónico/fisiología , Yeyuno/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Péptidos/efectos adversos , Péptidos/farmacología , Fosfoproteínas/antagonistas & inhibidores , Fosfoproteínas/metabolismo , Intercambiadores de Sodio-Hidrógeno/antagonistas & inhibidores , Intercambiadores de Sodio-Hidrógeno/metabolismo
14.
Environ Sci Technol ; 54(11): 6703-6712, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32343558

RESUMEN

To improve the performance of polymeric electrospun nanofiber mats (ENMs) for equilibrium passive sampling applications in water, we integrated two types of multiwalled carbon nanotubes (CNTs; with and without surface carboxyl groups) into polyacrylonitrile (PAN) and polystyrene (PS) ENMs. For 11 polar and moderately hydrophobic compounds (-0.07 ≤ logKOW ≤ 3.13), 90% of equilibrium uptake was achieved in under 0.8 days (t90% values) in nonmixed ENM-CNT systems. Sorption capacity of ENM-CNTs was between 2- and 50-fold greater than pure polymer ENMs, with equilibrium partition coefficients (KENM-W values) ranging from 1.4 to 3.1 log units (L/kg) depending on polymer type (hydrophilic PAN or hydrophobic PS), CNT loading (i.e., values increased with weight percent (wt %) of CNTs), and CNT type (i.e., greater uptake with carboxylated CNTs composites). During field deployment at Muddy Creek in North Liberty, Iowa, optimal ENM-CNTs (PAN with 20 wt % carboxylated CNTs) yielded atrazine concentrations in surface water with a 40% difference relative to analysis of a same-day grab sample. We also observed a mean percent difference of 30 (±20)% when comparing ENM-CNT sampler results to grab sample data collected within 1 week of deployment. With their rapid, high capacity uptake and small material footprint, ENM-CNT equilibrium passive samplers represent a promising alternative to complement traditional integrative passive samplers while offering convenience over large volume grab sampling.


Asunto(s)
Nanofibras , Nanotubos de Carbono , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Iowa , Polímeros , Contaminantes Químicos del Agua/análisis
15.
Environ Sci (Camb) ; 6(3): 622-634, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34306712

RESUMEN

Uranium (U) contamination of drinking water often affects communities with limited resources, presenting unique technology challenges for U6+ treatment. Here, we develop a suite of chemically functionalized polymer (polyacrylonitrile; PAN) nanofibers for low pressure reactive filtration applications for U6+ removal. Binding agents with either nitrogen-containing or phosphorous-based (e.g., phosphonic acid) functionalities were blended (at 1-3 wt.%) into PAN sol gels used for electrospinning, yielding functionalized nanofiber mats. For comparison, we also functionalized PAN nanofibers with amidoxime (AO) moieties, a group well-recognized for its specificity in U6+ uptake. For optimal N-based (Aliquat® 336 or Aq) and P-containing [hexadecylphosphonic acid (HPDA) and bis(2-ethylhexyl)phosphate (HDEHP)] binding agents, we then explored their use for U6+ removal across a range of pH values (pH 2-7), U6+ concentrations (up to 10 µM), and in flow through systems simulating point of use (POU) water treatment. As expected from the use of quaternary ammonium groups in ion exchange, Aq-containing materials appear to sequester U6+ by electrostatic interactions; while uptake by these materials is limited, it is greatest at circumneutral pH where positively charged N groups bind negatively charged U6+ complexes. In contrast, HDPA and HDEHP perform best at acidic pH representative of mine drainage, where surface complexation of the uranyl cation likely drives uptake. Complexation by AO exhibited the best performance across all pH values, although U6+ uptake via surface precipitation may also occur near circumneutral pH value and at high (10 µM) dissolved U6+ concentrations. In simulated POU treatment studies using a dead-end filtration system, we observed U removal in AO-PAN systems that is insensitive to common co-solutes in groundwater (e.g., hardness and alkalinity). While more research is needed, our results suggest that only 80 g (about 0.2 lbs.) of AO-PAN filter material would be needed to treat an individual's water supply (contaminated at ten-times the U.S. EPA Maximum Contaminant Level for U) for one year.

16.
J Mol Med (Berl) ; 96(8): 831-843, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29967942

RESUMEN

Impaired salt and water absorption is a hallmark of diarrhea in IBD. In the present study, the therapeutic effect of continuous anti-TNFα treatment on the progression of inflammation and colonic transport dysfunction during chronic dextran sulfate sodium (DSS)-induced colitis was investigated. Chronic colitis was induced by three DSS exposure cycles. Mice received TNFα monoclonal antibody treatment twice weekly after the end of the first 5-day DSS drinking period. Mice developed chronic DSS-induced colitis characterized by a typical immune cell infiltration composed of CD3+ T cells and CD68+ macrophages, both expressing high levels of the pro-inflammatory cytokines IL-1ß and TNFα, a loss of NHE3 and PDZK1 in the brush border region of the absorptive enterocyte and a decrease of colonic fluid absorption in vivo, measured by colonic single pass perfusion. Concomitant anti-TNFα treatment resulted in a significant reduction of mucosal immune cell infiltration and expression of the pro-inflammatory cytokines IL-1ß and TNFα. It also resulted in a normalization of NHE3-mediated fluid absorption and a restoration of NHE3 and PDZK1 location in the apical and subapical region of the enterocytes. Here, we show for the first time that in this chemically induced murine colitis model, anti-TNFα treatment significantly decreased inflammatory activity, improved mucosal integrity and restored transport function despite an ongoing inflammatory insult. Anti-TNFα treatment may therefore be beneficial in patients with IBD even in spite of an absence of complete mucosal healing. KEY MESSAGES: Chronic DSS treatment caused a loss of NHE3 and PDZK1 in the brush border region of the absorptive enterocyte and decreases colonic fluid absorption. In DSS-induced colitis, anti-TNFα treatment reduced mucosal immune cell infiltration and expression of the pro-inflammatory cytokines IL-1ß and TNFα. In DSS-induced colitis, anti-TNFα treatment normalized NHE3-mediated fluid absorption and restored NHE3 and PDZK1 location in the enterocytes. In DSS-induced colitis, anti-TNFα treatment decreased inflammatory activity, improved mucosal integrity, and restored transport function.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Colitis/etiología , Colitis/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Colitis/tratamiento farmacológico , Colitis/patología , Citocinas/metabolismo , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Absorción Gastrointestinal/efectos de los fármacos , Inmunohistoquímica , Mediadores de Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/etiología , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
17.
Environ Sci Process Impacts ; 19(11): 1445-1456, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29086783

RESUMEN

We fabricated a suite of polymeric electrospun nanofiber mats (ENMs) and investigated their performance as next-generation passive sampler media for environmental monitoring of organic compounds. Electrospinning of common polymers [e.g., polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), and polystyrene (PS), among others] yielded ENMs with reproducible control of nanofiber diameters (from 50 to 340 nm). The ENM performance was investigated initially with model hydrophilic (aniline and nitrobenzene) and hydrophobic (selected PCB congeners and dioxin) compounds, generally revealing fast chemical uptake into all of these ENMs, which was well described by a one compartment, first-order kinetic model. Typical times to reach 90% equilibrium (t90%) were ≤7 days under mixing conditions for all the ENMs and <0.5 days for the best performing materials under static (i.e., no mixing) conditions. Collectively, these short equilibrium timescales suggest that ENMs may be used in the field as an equilibrium-passive sampler, at least for our model compounds. Equilibrium partitioning coefficients (KENM-W, L kg-1) averaged 2 and 4.7 log units for the hydrophilic and hydrophobic analytes, respectively. PAN, PMMA and PS were prioritized for additional studies because they exhibited not only the greatest capacity for simultaneous uptake of the entire model suite (log KENM-W ∼1.5-6.2), but also fast uptake. For these optimized ENMs, the rates of uptake into PAN and PMMA were limited by aqueous phase diffusion to the nanofiber surface, and the rate-determining step for PS was analyte specific. Sorption isotherms also revealed that the environmental application of these optimized ENMs would occur within the linear uptake regime. We examined the ENM performance for the measurement of pore water concentrations from spiked soil and freshwater sediments. Soil and sediment studies not only yielded reproducible pore water concentrations and comparable values to other passive sampler materials, but also provided practical insights into ENM stability and fouling in such systems. Furthermore, fast uptake for a suite of structurally diverse hydrophilic and moderately hydrophobic compounds was obtained for PAN and PS, with t90% ranging from 0.01 to 4 days with mixing and KENM-W values ranging from 1.3 to 3.2 log units. Our findings show promise for the development and use of ENMs as equilibrium-passive samplers for a range of organic pollutants across soil/sediment and water systems.


Asunto(s)
Monitoreo del Ambiente/métodos , Modelos Teóricos , Nanofibras/química , Compuestos Orgánicos/análisis , Polímeros/química , Contaminantes Químicos del Agua/análisis , Adsorción , Monitoreo del Ambiente/instrumentación , Agua Dulce/química , Sedimentos Geológicos/química , Interacciones Hidrofóbicas e Hidrofílicas , Polímeros/síntesis química , Propiedades de Superficie
18.
Tumour Biol ; 34(3): 1825-31, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23504587

RESUMEN

Studies investigating the association between cytochrome glutathione S-transferase P1 (GSTP1) Ala114Val polymorphism and colorectal cancer (CRC) risk report conflicting results. The aim of this study was to quantitatively summarize the evidence for such a relationship. Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine databases. Summary odds ratios (ORs) and 95 % confidence intervals (95 % CIs) for GSTP1 polymorphism and CRC were calculated in a fixed effects model (the Mantel-Haenszel method) and a random effects model (the DerSimonian and Laird method) when appropriate. The pooled ORs were performed for co-dominant model (ValVal vs. AlaAla, AlaVal vs. AlaAla), dominant model (ValVal + AlaVal vs. AlaAla), and recessive model (ValVal vs. AlaVal + AlaAla). This meta-analysis included seven case-control studies, which included 3,173 CRC cases and 3,323 controls. Overall, the variant genotypes (ValVal and AlaVal) of the Ala114Val were not associated with CRC risk when compared with the wild-type AlaAla homozygote. Similarly, no associations were found in the dominant and recessive models. When stratifying for ethnicity, Hardy-Weinberg equilibrium in controls, study sample size, and source of controls, a significantly increased risk was observed among Asians (AlaVal vs. AlaAla, OR=1.67, 95 % CI=1.08-2.59; dominant model, OR=1.74, 95 % CI=1.14-2.67). No heterogeneity or publication bias was found in the present study. This meta-analysis suggests that the GSTP1 Ala114Val polymorphism may not be associated with CRC risk, while the observed increase in risk of CRC may be due to small-study bias.


Asunto(s)
Neoplasias Colorrectales/etiología , Predisposición Genética a la Enfermedad , Gutatión-S-Transferasa pi/genética , Polimorfismo Genético/genética , Estudios de Casos y Controles , Humanos , Factores de Riesgo
19.
Hepatogastroenterology ; 58(110-111): 1828-33, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21940351

RESUMEN

BACKGROUND/AIMS: In this study, we applied the SELDI-TOF-MS technique for the identification of gastric cancer-specific protein markers and sample SELDI protein profiling to distinguish gastric cancer patients of the efficacy of neoadjuvant chemotherapy from a no efficacy population. METHODOLOGY: Gastric tissue samples from 8 paired patients with gastric cancer, from whom clinical and histopathological data concerning patients and carcinomas were available, were analyzed. We scanned 8 paired samples (chemotherapy sensitive and insensitive) by SELDI-TOF-MS. RESULTS: The data generated 409 high sensitive and reproducibly peaks. From the distribution of the peaks, most of the detectable peaks are in the range from 3000-7000m/z. One potential protein at 7044m/z is Guanine nucleotide-binding protein (GBG7_Human 060262). CONCLUSIONS: In summary, we present novel differential expressed protein profile for neoadjuvant chemotherapy. This data set will help us to understand the mechanism for the chemotherapy resistance. Our data suggested the presence of GBG7 indicate patient will receive better prognosis of neoadjuvant chemotherapy.


Asunto(s)
Biomarcadores de Tumor/análisis , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Biología Computacional , Interpretación Estadística de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Valor Predictivo de las Pruebas
20.
Eur J Cancer ; 44(11): 1596-602, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18492607

RESUMEN

Chronic infection of hepatitis B virus (HBV) is one of the major causes of hepatocellular carcinoma (HCC) in the world. The hepatitis B virus X protein (HBx) is implicated in HCC development, although its oncogenic role remains controversial. HBx is a multifunctional regulator that modulates transcription, signal transduction, cell cycle progress, and DNA repair by directly or indirectly interacting with host factors. We constructed the HBx stably expressing HepG2 cell line to investigate the impact of HBx on intra-S-phase checkpoint induced by mitomycin C (MMC). The HBx transformed HepG2 cells are more sensitive to MMC treatment and showed defective radioresistant DNA synthesis compared to the control cell line transformed with empty vector. With DNA content assay, HBx transformed cells showed defective S phase arrest and a consequent G2/M arrest after MMC treatment. HBx impaired the ATR dependent phosphorylation of Chk1 and monoubiquitination of FANCD2. Overexpression of ATR reverted the MMC induced phenotype of Chk1 and FANCD2 in HBx transformed cells. The defect of intra-S-phase checkpoint resulted in accumulation of genomic instability. In conclusion, HBx disrupts intra-S-phase checkpoint induced by MMC through ATR-Chk1 and ATR-FANCD2 pathways.


Asunto(s)
Daño del ADN/efectos de los fármacos , Mitomicina/farmacología , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Fase S/efectos de los fármacos , Transactivadores/farmacología , Carcinoma Hepatocelular/virología , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Hepatitis B Crónica/complicaciones , Humanos , Neoplasias Hepáticas/virología , Proteínas Quinasas/metabolismo , Proteínas Reguladoras y Accesorias Virales
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