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1.
Mol Cell Biochem ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625514

RESUMEN

The treatment of ovarian cancer remains a medical challenge and its malignant progression is connected with obvious changes in both tissue and cell stiffness. However, the accurate mechanical-responsive molecules and mechanism remains unclear in ovarian cancer. Based on our previous results combined with the crucial regulatory role of STAT3 in the malignant progression of various cancer types, we want to investigate the relationship between STAT3 and matrix stiffness in ovarian cancer and further explore the potential mechanisms. Collagen-coated polyacrylamide gels (1, 6, and 60 kPa) were prepared to mimic soft or hard matrix stiffness. Western blotting, qRT-PCR, flow cytometry, IHC, EdU assays, and TEM were used to evaluate the effect of STAT3 in vitro under different matrix stiffnesses. Furthermore, a BALB/c nude mouse model was established to assess the relationship in vivo. Our results confirmed the differential expression of STAT3/p-STAT3 not only in normal and malignant ovarian tissues but also under different matrix stiffnesses. Furthermore, we verified that STAT3 was a mechanically responsive gene both in vitro and in vivo, and the mechanical response was carried out by altering the migration-related molecules (TNFAIP1) and adhesion-related molecules (LPXN, CNN3). The novel findings suggest that STAT3, a potential therapeutic target for clinical diagnosis and treatment, is a mechanically responsive gene that responds to matrix stiffness, particularly regulation in migration and adhesion in the progression of ovarian cancer.

2.
Med Sci Monit ; 30: e943063, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809818

RESUMEN

BACKGROUND The correlation between serum creatinine levels and the long-term prognosis of patients undergoing percutaneous coronary intervention (PCI) has not yet been systematically investigated. This study aimed to evaluate the association between long-term prognosis and serum creatinine levels in patients after PCI. MATERIAL AND METHODS This was an observational cohort study of 2533 patients who received PCI and completed serum creatinine and other tests in China. The study's primary prognostic indicators were the frequency of clinical adverse events, all-cause death, cardiac death, acute myocardial infarction, and stroke. All-cause death referred to death from all causes during the follow-up period, whereas cardiac death was death due to cardiac injury resulting in severe cardiac dysfunction or failure. Clinical events included death, ischemia, and stroke. Yao et al completed the entire study and uploaded the data to the DATADRYAD website. We used only this data for secondary analysis. RESULTS The study involved 2533 participants, with a mean age of 59.9±11.1 years and a median follow-up of 29.8 months. The analysis, controlling for confounding factors, revealed a positive correlation between serum creatinine and all-cause death (OR: 2.178, 95% CI: 1.317-3.603, P<0.05), which was confirmed by the results of sensitivity analysis (P for trend <0.05). However, no direct linear correlation was found between serum creatinine and acute myocardial infarction, cardiac death, or stroke. CONCLUSIONS There was a linear correlation between serum creatinine and all-cause death in the long-term prognosis of patients after PCI, independent of acute myocardial infarction, cardiac death, and stroke.


Asunto(s)
Creatinina , Intervención Coronaria Percutánea , Humanos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Masculino , Persona de Mediana Edad , Femenino , Creatinina/sangre , Pronóstico , Anciano , China/epidemiología , Infarto del Miocardio/sangre , Infarto del Miocardio/mortalidad , Causas de Muerte , Factores de Riesgo , Estudios de Cohortes , Accidente Cerebrovascular/sangre
3.
Artículo en Inglés | MEDLINE | ID: mdl-38466060

RESUMEN

Objective: To explore the effect of interdisciplinary collaboration in emergency nursing using the strengths-weaknesses-opportunities-threats (SWOT) model on patients with acute myocardial infarction (AMI). Methods: Eighty AMI patients undergoing rescue treatment at Affiliated Hospital of Inner Mongolia Medical University from October 2020 to June 2022 were selected and randomly divided into the SWOT group and the control group. The patients in the control group received routine emergency nursing intervention, while those in the SWOT group were given interdisciplinary collaboration using the SWOT model. The emergency-related time, cardiac function indicators, incidence of adverse events, quality of life, and nursing satisfaction were compared between the two groups. Results: The waiting time, triage assessment time, electrocardiogram examination time, emergency treatment time, PCI duration and ICU stay time in SWOT group were significantly shorter than those in control group. The left ventricular end-systolic diameter (LVESd), left ventricular end-diastolic diameter (LVEDd), and left ventricular ejection fraction (LVEF) in the SWOT group were all superior to those in the control group. The SWOT group had a significantly lower incidence rate of adverse events than the control group. The quality of life scores of SWOT group were higher than those of control group. The nursing satisfaction in the SWOT group was higher than that in the control group. Conclusion: Interdisciplinary collaboration using the SWOT model for AMI patients can effectively shorten the rescue time, ameliorate cardiac function indicators, reduce the risk of adverse events, improve patients' quality of life, and enhance nursing satisfaction.

4.
J Asian Nat Prod Res ; : 1-16, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38975978

RESUMEN

The flavonoid compound chinonin is one of the main active components of Rhizoma anemarrhena with multiple activities, including anti-inflammatory and antioxidant properties, protection of mitochondrial function and regulation of immunity. In this paper, we reviewed recent research progress on the protective effect of chinonin on brain injury in neurological diseases. "Chinonin" OR "Mangiferin" AND "Nervous system diseases" OR "Neuroprotection" was used as the terms for search in PumMed. After discarding duplicated and irrelevant articles, a total of 23 articles relevant to chinonin published between 2012 and 2023 were identified in our study.

5.
Environ Geochem Health ; 45(3): 585-606, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35347514

RESUMEN

In order to expound on the present situation and potential risk of road dust heavy metals in major cities, a total of 114 literatures mainly over the past two decades, involving more than 5000 sampling sites in 61 cities of 21 countries, were screened through the collection and analysis of research papers. The concentration, sources, distribution, health risk, sample collection, and analytical methods of heavy metal research on road dust in cities around the world are summarized. The results show that Cd, Zn, and Cu in many urban road dusts in the world are higher than the grade II of the Chinese maximum allowable concentration of potentially toxic elements in the soil. Geo-accumulation index values show that Pb > Cd > Zn > Cu had the highest contamination levels. Hazard index assessment indicates Pb and Cr had the highest potential health risk, especially for children in which ingestion was found as the main exposure pathway. Moreover, through comparative analysis, it is found that some pollutants are higher in developed and industrialized cities and transport (53%) followed by industrial emissions (35%) provide the major contributions to the sources of heavy metals.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Niño , Humanos , Monitoreo del Ambiente/métodos , Polvo/análisis , Ciudades , Cadmio/análisis , Plomo/análisis , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Medición de Riesgo/métodos , China
6.
J Cell Physiol ; 237(1): 118-127, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34297411

RESUMEN

IRE1 is an important central regulator of unfolded protein response (UPR) in the endoplasmic reticulum (ER) because of its ability to regulate cell fate as a function of stress sensing. When misfolded proteins accumulated in chondrocytes ER, IRE1 disintegrates with BIP/GRP78 and undergoes dimer/oligomerization and transautophosphorylation. These two processes are mediated through an enzyme activity of IRE1 to activate endoribonuclease and generates XBP1 by unconventional splicing of XBP1 messenger RNA. Thereby promoting the transcription of UPR target genes and apoptosis. The deficiency of inositol-requiring enzyme 1α (IRE1α) in chondrocytes downregulates prosurvival factors XBP1S and Bcl-2, which enhances the apoptosis of chondrocytes through increasing proapoptotic factors caspase-3, p-JNK, and CHOP. Meanwhile, the activation of IRE1α increases chondrocyte viability and reduces cell apoptosis. However, the understanding of IRE1 responses and cell death fate remains controversial. This review provides updated data about the role IRE1 plays in chondrocytes and new insights about the potential efficacy of IRE1 regulation in cartilage repair and osteoarthritis treatment.


Asunto(s)
Condrocitos , Osteoartritis , Apoptosis/genética , Condrocitos/metabolismo , Estrés del Retículo Endoplásmico/genética , Endorribonucleasas/genética , Endorribonucleasas/metabolismo , Humanos , Osteoartritis/genética , Osteoartritis/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Respuesta de Proteína Desplegada/genética , Proteína 1 de Unión a la X-Box/genética
7.
Biochem Biophys Res Commun ; 626: 167-174, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-35994826

RESUMEN

Nonalcoholic steatohepatitis (NASH) is the development of non-alcoholic fatty liver disease (NAFLD) and a key element in the exacerbation of NAFLD. Since there are currently no drugs approved by the U.S. Food and Drug Administration to treat this disease, the search for treatments that can be translated into clinical use is urgent. Butyrolactone I (BLI), isolated from Aspergillus terreus, is an active compound possessing multiple biological activities. However, the effects of BLI on NASH have never been reported. In this study, RAW264.7 cells stimulated by lipopolysaccharide (LPS) were applied to study the anti-inflammatory effect and the underlying mechanisms of BLI in vitro. Following this, mice fed with high-fat and -fructose diet (HFFD) were used to explore the alleviation of NASH by BLIin vivo. We found that BLI attenuated inflammation in LPS-induced RAW264.7 cells by inhibiting the NF-κB signaling pathway and downregulating the expression of iNOS and COX-2. Moreover, results of experiments in vivo demonstrated that BLI reduced serum transaminase levels, decreased hepatic fat accumulation, inhibited inflammation, suppressed oxidative stress, and ameliorated liver fibrosis. For the first time, we investigated the role of BLI in the treatment of murine NASH. We found that BLI alleviates NASH partly by inhibiting the NF-κB pathway of signaling. Given its hepatoprotective effects and non-toxic properties, BLI can be a novel and effective drug for NASH patients.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , 4-Butirolactona/análogos & derivados , Animales , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Lipopolisacáridos/farmacología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Transducción de Señal
8.
Sex Transm Dis ; 49(3): 197-203, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34670941

RESUMEN

BACKGROUND: Human immunodeficiency virus (HIV) partner services are an essential component of comprehensive HIV prevention and care. We examined factors associated with partner notification, HIV testing, and HIV positivity among partners of HIV-diagnosed persons (index persons) contacted by Centers for Disease Control and Prevention (CDC)-funded state and local health departments. METHODS: We analyzed partner service data submitted to the CDC by 61 state and local health departments from 2013 to 2017. Using multivariate Poisson regression-adjusted for clustering effects among partners reported by a common index person-we assessed associations between 3 outcomes of interest (partner notification, HIV testing, and HIV positivity) and the demographic characteristics, risk behaviors, geographic region, and service year of index persons and their partners. RESULTS: A total of 51,368 sexual and/or needle-sharing partners were matched with 33,524 index persons. Of notifiable partners, 97.2% were notified of their potential HIV exposure, and 52.3% were tested for HIV. Among 21,842 notified and tested partners, 23.8% were newly diagnosed with an HIV infection. Partner notification, HIV testing, and HIV positivity were associated with both partner and index person characteristics (individually and interactively), geographic region, and year of service. CONCLUSIONS: Partner service programs provided through CDC-funded health departments were effective in both partner notification and identification of undiagnosed HIV infection among partners. However, HIV testing rate among notified partners remained low. Implementing strategies to address gaps in HIV testing can contribute toward ending the HIV epidemic in the United States.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , Trazado de Contacto , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Seropositividad para VIH/epidemiología , Humanos , Conducta Sexual , Parejas Sexuales , Estados Unidos/epidemiología
9.
Gastrointest Endosc ; 95(6): 1138-1146.e2, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34973966

RESUMEN

BACKGROUND AND AIMS: The quality of EGD is a prerequisite for a high detection rate of upper GI lesions, especially early gastric cancer. Our previous study showed that an artificial intelligence system, named intelligent detection endoscopic assistant (IDEA), could help to monitor blind spots and provide an operation score during EGD. Here, we verified the effectiveness of IDEA to help evaluate the quality of EGD in a large-scale multicenter trial. METHODS: Patients undergoing EGD in 12 hospitals were consecutively enrolled. All hospitals were equipped with IDEA developed using deep convolutional neural networks and long short-term memory. Patients were examined by EGD, and the results were recorded by IDEA. The primary outcome was the detection rate of upper GI cancer. Secondary outcomes were part scores, total scores, and endoscopic procedure time, which were analyzed by IDEA. RESULTS: A total of 17,787 patients were recruited. The total detection rate of cancer-positive cases was 1.50%, ranging from .60% to 3.94% in each hospital. The total detection rate of early cancer-positive cases was .36%, ranging from .00% to 1.58% in each hospital. The average total score analyzed by IDEA ranged from 64.87 ± 16.87 to 83.50 ± 9.57 in each hospital. The cancer detection rate in each hospital was positively correlated with total score (r = .775, P = .003). Similarly, the early cancer detection rate was positively correlated with total score (r = .756, P = .004). CONCLUSIONS: This multicenter trial confirmed that the quality of the EGD result is positively correlated with the detection rate of cancer, which can be monitored by IDEA. (Clinical trial registration number: ChiCTR2000029001.).


Asunto(s)
Neoplasias Gastrointestinales , Neoplasias Gástricas , Inteligencia Artificial , Endoscopía , Endoscopía del Sistema Digestivo/métodos , Humanos , Redes Neurales de la Computación , Neoplasias Gástricas/diagnóstico
10.
Cell Mol Biol (Noisy-le-grand) ; 67(5): 309-316, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35818238

RESUMEN

This study aimed to explore the effects of ultra-mini percutaneous nephrolithotomy (UMP) combined with ShuoTong ureteroscopy on the stress response, inflammation indicators and urokinase levels in patients with polycystic kidney disease and kidney stones. In this study, 42 patients with polycystic kidney disease and kidney stones diagnosed and treated in our hospital from February 2018 to February 2021 were selected as the research objects. They were randomly divided into the control group and the study group, with 21 cases in each group, and the control group adopted Ultra-mini percutaneous nephrolithotomy treatment; the study group was combined with ShuoTong ureteroscopy on the basis of the control group, and compared and analyzed the stress response, inflammation indexes, urokinase level, renal function, complications and stone clearance rate of the two groups of patients. After treatment, the average operation time, channel establishment time, hemoglobin decline, number of puncture channels, and hospital stay in the study group were significantly shorter than those in the control group (P<0.05); after treatment, the reduction in CRP and PCT in the study group was significantly higher than that in the control group The increase of Ang I and Ang II in the control group was significantly lower than that in the control group (P<0.05); the improvement of PGE2, NO, and LPO levels in the study group was significantly higher than that in the control group after treatment (P<0.05); the study group TH, Cys- The levels of C and ß2-MG were significantly lower than those of the control group; the UK levels of the study group were significantly lower than those of the control group (P<0.05); the complication rate of 14.29% in the study group after treatment was significantly lower than that of the control group 33.33%; the study group The stone clearance rate of 95.24% was significantly higher than that of the control group 80.95% (P<0.05). In general, UMP combined with ShuoTong ureteroscopy is used to treat polycystic kidney with kidney stones, accurately determine the tip position of the needle sheath, ensure that the needle sheath enters the collection system to adjust its position, reduce patient stress and inflammation, improve safety and feasibility, and is worthy of clinical practice Promote applications.


Asunto(s)
Cálculos Renales , Nefrolitotomía Percutánea , Enfermedades Renales Poliquísticas , Ureteroscopía , Humanos , Inflamación/etiología , Cálculos Renales/complicaciones , Cálculos Renales/cirugía , Enfermedades Renales Poliquísticas/complicaciones , Enfermedades Renales Poliquísticas/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Activador de Plasminógeno de Tipo Uroquinasa
11.
BMC Musculoskelet Disord ; 22(1): 480, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34034718

RESUMEN

BACKGROUND: Wnt-catenin signaling antagonists sclerostin and dickkopf-related protein-1 (Dkk-1) inhibit bone formation and are involved in the pathogenesis of postmenopausal osteoporosis (PO). However, the association between sclerostin and Dkk-1 and bone mineral density (BMD) in women with PO remains unclear. OBJECTIVE: This study aimed to determine the association between sclerostin and Dkk-1 and BMD, bone microarchitecture, and bone strength in PO. METHODS: Trabecular bone specimens were obtained from the femoral heads of 76 Chinese women with PO who underwent hip arthroplasty for femoral neck fractures. Micro-computed tomography (Micro-CT) was used to assess the BMD and bone microarchitecture of the trabecular bone. Subsequently, a mechanical test was performed. Finally, sclerostin and Dkk-1 in the bone were measured by enzyme-linked immunosorbent (Elisa) assay. Serum ionized serum ionised calcium, propeptide of type 1 collagen, C-terminal ß-telopeptide of type-1 collagen, sclerostin, and Dkk-1 were also detected. RESULTS: Bone sclerostin was positively correlated with serum ionised calcium, serum sclerostin, BMD, bone volume/tissue volume (BV/TV), trabecular number (Tb.N), maximum compressive force, and yield strength (r = 0.32, 0.906, 0.355, 0.401, 0.329, 0.355, and 0.293, respectively, P < 0.05) and negatively correlated with age and trabecular separation (Tb.Sp) (r = - 0.755 and - 0.503, respectively, P < 0.05). Bone Dkk-1 was positively correlated with serum ionised calcium, serum Dkk-1, BMD, BV/TV, trabecular thickness, Tb.N, maximum compressive force, yield strength, and Young's modulus (r = 0.38, 0.809, 0.293, 0.293, 0.228, 0.318, 0.352, 0.315, and 0.266, respectively, P < 0.05) and negatively correlated with age and Tb.Sp (r = - 0.56 and - 0.38, respectively, P < 0.05). Serum levels of sclerostin and Dkk-1 reflected the levels of sclerostin and Dkk-1 in the bone. CONCLUSION: Bone sclerostin and Dkk-1 were positively correlated with BMD in women with PO, and higher levels of bone sclerostin and Dkk-1 might predict better BMD, bone microarchitecture, and bone strength. The potential molecular mechanisms still require further study.


Asunto(s)
Densidad Ósea , Osteoporosis Posmenopáusica , Proteínas Adaptadoras Transductoras de Señales , Proteínas Morfogenéticas Óseas , Femenino , Marcadores Genéticos , Humanos , Osteoporosis Posmenopáusica/diagnóstico por imagen , Microtomografía por Rayos X
12.
Opt Lett ; 45(15): 4352, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32735296

RESUMEN

This publisher's note contains corrections to Opt. Lett.45, 3816 (2020)OPLEDP0146-959210.1364/OL.397152.

13.
Opt Lett ; 45(13): 3816-3819, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32630962

RESUMEN

Memory-effect-based speckle correlation is one of the most practical techniques for imaging through scattering opaque media, where a light source with low spatial coherence and moderate bandwidth plays a pivotal role. Usually, a rapidly rotating diffuser is applied to make the light source spatially decoherent. Here, an all-fiber-based low-spatial-coherence light source is proposed and demonstrated for such speckle-correlated imaging. The illumination structure is greatly simplified, the lightening efficiency is enhanced, and the wavelength is extended to the near-infrared band, which is favorable for a larger memory effect range and deeper penetrating depth through opacity. Moreover, the proposed local illumination method can identify the orientation of the object, which has not been revealed by former methods. This work would facilitate the research in optical biomedical imaging and broaden the applications of multimode random fiber lasers.

14.
MMWR Morb Mortal Wkly Rep ; 69(2): 35-39, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31945033

RESUMEN

Transgender women* in the United States are disproportionately affected by human immunodeficiency virus (HIV) infection because of multiple factors, including stigma related to gender identity, unstable housing, limited employment options, and high-risk behaviors, such as sex work, unprotected receptive anal intercourse, and injection drug use, that tend to increase their vulnerability to becoming infected with HIV (1,2). In a recent meta-analysis of 88 U.S. studies conducted during 2006-2017, the mean estimated laboratory-confirmed prevalence of HIV infection among transgender women was 14.2%, and the mean self-reported prevalence estimate was 21.0% (3). The Ending the HIV Epidemic initiative calls for accelerating the implementation of evidence-based strategies in the right geographic areas targeted to the right persons to end the HIV epidemic in the United States (4). HIV partner services are effective strategies offered by public health workers to persons with a diagnosis of HIV infection (index persons) and their sex or needle-sharing partners (partners), who are notified of potential HIV exposure and offered HIV testing and related services. CDC analyzed HIV partner services data submitted by 61 health departments† during 2013-2017. Among 208,304 index persons, 1,727 (0.8%) were transgender women. Overall, 71.5% of index transgender women were interviewed for partner services, which was lower than that for all index persons combined (81.1%). Among 1,089 transgender women named as partners by index persons, 71.2% were notified of potential HIV exposure, which was lower than that for all partners combined (77.1%). Fewer than half (46.5%) of notified transgender women partners were tested for HIV, and approximately one in five (18.6%) of those who were tested received a new diagnosis of HIV infection, slightly higher than for all partners combined (17.6%). Additional efforts are needed to effectively implement partner services among transgender women and identify those whose infection with HIV is undiagnosed, provide timely prevention and care services, reduce HIV transmission, and contribute to ending the HIV epidemic.


Asunto(s)
Atención a la Salud , Infecciones por VIH/terapia , Parejas Sexuales , Personas Transgénero , Adolescente , Adulto , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Estados Unidos/epidemiología , Adulto Joven
15.
Nanotechnology ; 31(39): 394002, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-32454470

RESUMEN

The exploitation of carbon nanotube (CNT) and metal-organic framework (MOF) composite materials has been highly desirable in a number of applications. However, the construction of high dispersibility and stability CNT/MOF complex structures is still an enormous challenge. Herein, a novel assembly method is established for the construction of a CNT/Ni-MOF (0.1 CNT/MOF, 0.2 CNT/MOF, 0.3 CNT/MOF) interpenetrated structure by a solvothermal process. The MOFs can be robustly anchored on the surface of CNTs. Through a series of characterizations, the MOF can be comfortably integrated into the CNT fibers, which exhibits the enhancement of carrier mobility and fluorescence properties. The microwave absorption properties of the CNT/MOF are explored by a vector network analyzer. The 0.1 CNT/MOF has a maximum absorption of -9.2 dB at 18 GHz with a thickness of 5 mm, while the 0.2 CNT/MOF has a maximum absorption of -24.32 dB at 4.5 GHz with a thickness of 5 mm, a performance maximum. Therefore, the 0.2 CNT/MOF structures are potential candidates to ameliorate the microwave absorption properties.

16.
Nanotechnology ; 31(41): 414001, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-32559751

RESUMEN

Carbon-nanotube-based composites are highly desirable for addressing the difficulties relevant to the quality of electromagnetic wave absorbers. The introduction of lightweight nanocomposites for constructing new structures has been widely studied due to the transformation in impedance matching and attenuation. In this paper, a novel carbon nanotube-graphene oxide-zeolitic imidazolate framework-8 (CNT/RGO/ZIF-8) ternary hybrid structure was successfully fabricated by a facile solvothermal process. The ZIF-8 was entangled initially by carbon nanotubes via the π-π interaction between organic ligands and benzene ring structure in CNT. Then, the CNT/ZIF-8 composite was immobilized on the surface of RGO by interacting with the active functional group of RGO. The structure and performance for CNT, CNT/ZIF-8, and CNT/RGO/ZIF-8 were compared to investigate the interaction mechanisms between components, and CNT/ZIF-8 exhibited a distinct improvement for microwave absorption performance. Furthermore, the introduction of RGO can accelerate the amelioration of absorption characteristics. The interfacial bonding between CNT, RGO, and ZIF-8 exerts a great influence on the absorbing quality. The mechanism of absorption of electromagnetic waves was explained by the synergistic effects of conduction loss, polarization behaviors, and eddy current. The unique structure could offer new insights to exploit advanced microwave-absorption materials.

17.
Exp Cell Res ; 375(2): 1-9, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30641040

RESUMEN

We performed liquid chromatography-tandem mass spectrometry (LC-MS/MS) on control and TGF-ß1-exposed rat lung fibroblasts to identify proteins differentially expressed between cell populations. A total of 196 proteins were found to be differentially expressed in response to TGF-ß1 treatment. Guided by these results, we next determined whether similar changes in protein expression were detectable in the rat lung after chronic exposure to silica dust. Of the five proteins selected for further analysis, we found that levels of all proteins were markedly increased in the silica-exposed rat lung, including the proteins for the very low density lipoprotein receptor (VLDLR) and the transmembrane (type I) heparin sulfate proteoglycan called syndecan 2 (SDC2). Because VLDLR and SDC2 have not, to our knowledge, been previously linked to the pathobiology of silicosis, we next examined whether knockdown of either gene altered responses to TGF-ß1 in MRC-5 lung fibroblasts. Interestingly, we found knockdown of either VLDLR or SDC2 dramatically reduced collagen production to TGF-ß1, suggesting that both proteins might play a novel role in myofibroblast biology and pathogenesis of silica-induced pulmonary fibrosis. In summary, our findings suggest that performing LC-MS/MS on TGF-ß1 stimulated lung fibroblasts can uncover novel molecular targets of activated myofibroblasts in silica-exposed lung.


Asunto(s)
Fibroblastos/metabolismo , Silicosis/genética , Transcriptoma , Factor de Crecimiento Transformador beta/farmacología , Animales , Células Cultivadas , Colágeno/genética , Colágeno/metabolismo , Fibroblastos/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Receptores de LDL/genética , Receptores de LDL/metabolismo , Silicosis/metabolismo , Sindecano-2/genética , Sindecano-2/metabolismo
18.
J Environ Manage ; 268: 110702, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32510437

RESUMEN

The reactive nitrogen (N) loss of the rice cropping system in the arid region shows a different pattern from that of subtropical humid region due to different climate types and crop management. However, little attention has been paid to this region. To fill this knowledge gap, a two-year (2009-2010) field observation was conducted in the Ningxia irrigation region, northwest China, to explore the major pathway of N loss following local farmers' optimal practice. Further, we determined the site-specific emission factors of ammonia and nitrous oxide, rate of surface runoff and subsurface (leaching and seepage) to improve the inventory resolution of arid irrigation region. Results showed that ammonia volatilization (45%-49% of total N loss), leaching and seepage (30%-33% of total N loss) were proved to be the primary factors of N loss in rice paddy fields. The emission factor of ammonia (21%) and N leaching rate (7.5%) following farmers' practice were 2.1 and 5.4 times higher than the country-specific default value in China. The country-specific N runoff rate and emission factor of N2O could be directly adopted in this region. A 20% reduction of N fertilizer to farmers' practice (300 kg N ha-1) alongside the application of organic fertilizer (30% N in synthetic fertilizer was substituted by pig manure) were considered to be the optimal N rate in this region. Our study can narrow the gap between researches on N loss in arid regions and subtropical humid regions. Meanwhile, the results can provide specific advice on N loss mitigation for policy makers in arid irrigation regions.


Asunto(s)
Nitrógeno , Oryza , Agricultura , Animales , China , Fertilizantes , Óxido Nitroso , Suelo , Porcinos
19.
Ecotoxicol Environ Saf ; 184: 109624, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31487570

RESUMEN

In order to explore the response and adaptation mechanisms of photosynthesis of the leaves of mulberry (Morus alba L.) seedlings to saline-alkali stress. Photosynthetic activity, and the response of related proteomics of M. alba seedling leaves under NaCl and NaHCO3 stress were studied by using chlorophyll fluorescence and gas exchange technique combined with TMT proteomics. The results showed that NaCl stress had no significant effect on photosystem II (PSII) activity in M. alba seedling leaves. In addition, the expressions of proteins of the PSII oxygen-evolving complex (OEE3-1 and PPD4) and the LHCII antenna (CP24 10A, CP26, and CP29) were increased, and the photosystem I (PSI) activity in the leaves of M. alba seedlings was increased, as well as expressions of proteins, such as PsaF, PsaG, PsaH, PsaL, PsaN, and Ycf4. Under NaHCO3 stress, the activity of PSII and PSI and the expression of their protein complexes and the electron transfer-related proteins significantly decreased. NaCl stress had little effect on RuBP regeneration during dark reaction in the leaves and the expressions of glucose synthesis related proteins and net photosynthetic rate (Pn) did not decrease significantly. The leaves could adapt to NaCl stress by reducing stomatal conductance (Gs) and increasing water use efficiency (WUE). Under NaHCO3 stress, the expression of dark reaction-related proteins was mostly down-regulated, while Gs was reduced, which indicated that non-stomatal factors can be responsible for inhibition of carbon assimilation.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Morus/efectos de los fármacos , Estrés Salino , Bicarbonato de Sodio/toxicidad , Cloruro de Sodio/toxicidad , Adaptación Fisiológica/fisiología , Morus/metabolismo , Morus/fisiología , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Proteínas de Plantas/metabolismo , Proteómica , Plantones/efectos de los fármacos , Plantones/metabolismo , Plantones/fisiología
20.
Molecules ; 24(21)2019 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-31671678

RESUMEN

Nitrogen-doped and undoped titanium dioxide nanoparticles were successfully fabricated by simple chemical method and characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray (EDX), and transmission electron microscopy (TEM) techniques. The reduction in crystalline size of TiO2 nanoparticles (from 20-25 nm to 10-15 nm) was observed by TEM after doping with N. Antibacterial, antifungal, antioxidant, antidiabetic, protein kinase inhibition and cytotoxic properties were assessed in vitro to compare the therapeutic potential of both kinds of TiO2 nanoparticles. All biological activities depicted significant enhancement as a result of addition of N as doping agent to TiO2 nanoparticles. Klebsiella pneumoniae has been illuminated to be the most susceptible bacterial strain out of various Gram-positive and Gram-negative isolates of bacteria used in this study. Good fungicidal activity has been revealed against Aspergillus flavus. 38.2% of antidiabetic activity and 80% of cytotoxicity has been elucidated by N-doped TiO2 nanoparticles towards alpha-amylase enzyme and Artemia salina (brine shrimps), respectively. Moreover, notable protein kinase inhibition against Streptomyces and antioxidant effect including reducing power and % inhibition of DPPH has been demonstrated. This investigation unveils the more effective nature of N-doped TiO2 nanoparticles in comparison to undoped TiO2 nanoparticles indicated by various biological tests. Hence, N-doped TiO2 nanoparticles have more potential to be employed in biomedicine for the cure of numerous infections.


Asunto(s)
Nanopartículas/uso terapéutico , Nitrógeno/química , Titanio/uso terapéutico , Animales , Antibacterianos/farmacología , Antifúngicos/farmacología , Antioxidantes/farmacología , Artemia/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Hipoglucemiantes/farmacología , Pruebas de Sensibilidad Microbiana , Nanopartículas/ultraestructura , Tamaño de la Partícula , Inhibidores de Proteínas Quinasas/farmacología , Difracción de Rayos X
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