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1.
Nat Immunol ; 20(9): 1220-1230, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31285626

RESUMEN

Regulatory T (Treg) cells play a major role in the development of an immunosuppressive tumor microenvironment. The origin of intratumoral Treg cells and their relationship with peripheral blood Treg cells remain unclear. Treg cells consist of at least three functionally distinct subpopulations. Here we show that peripheral blood CD45RA-FOXP3hi Treg cells (Treg II cells) are phenotypically closest to intratumoral Treg cells, including in their expression of CCR8. Analyses of T cell antigen receptor repertoires further support the hypothesis that intratumoral Treg cells may originate primarily from peripheral blood Treg II cells. Moreover, the signaling responsiveness of peripheral blood Treg II cells to immunosuppressive, T helper type 1 (TH1) and T helper type 2 (TH2) cytokines reflects intratumoral immunosuppressive potential, and predicts future relapse in two independent cohorts of patients with breast cancer. Together, our findings give important insights into the relationship between peripheral blood Treg cells and intratumoral Treg cells, and highlight cytokine signaling responsiveness as a key determinant of intratumoral immunosuppressive potential and clinical outcome.


Asunto(s)
Neoplasias de la Mama/patología , Tolerancia Inmunológica/inmunología , Recurrencia Local de Neoplasia/patología , Linfocitos T Reguladores/inmunología , Citocinas/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal/inmunología , Células TH1/inmunología , Células Th2/inmunología , Resultado del Tratamiento , Microambiente Tumoral/inmunología
2.
J Org Chem ; 88(13): 8034-8041, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37319302

RESUMEN

A tandem reaction for the synthesis of phenanthrenes from arynes and α-(bromomethyl)styrenes is reported. The transformation proceeds via an ene reaction of α-(bromomethyl)styrenes with arynes, followed by a [4 + 2] cycloaddition reaction. The reaction generates 9-benzylphenanthrene derivatives in moderate to excellent yields.


Asunto(s)
Fenantrenos , Estirenos , Reacción de Cicloadición , Ciclización
3.
Physiol Plant ; 175(4): e13986, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37615999

RESUMEN

Soil pollution with lead (Pb) has become a serious global concern, adversely affecting the forest ecosystem. This study was conducted to investigate the effects of corn straw on the remediation efficiency of Pb-contaminated soil using Populus deltoides. Female and male P. deltoides cuttings were subjected to soil spiked with 900 mg kg-1 Pb and amended with 5% (v/v) corn straw biochar for 90 days. Under Pb stress, the addition of biochar significantly increased the total biomass accumulation by 29% in females and 26% in males. However, without the addition of biochar, the biomass accumulation was significantly reduced by 11% in females and 3% in males under Pb stress. Females showed a higher uptake and accumulation of Pb in roots and leaves, while males accumulated more Pb in roots and stems and exhibited an increased anti-oxidative capacity. Biochar addition alleviated Pb toxicity in both male and female P. deltoides by immobilizing Pb ion in the soil, reducing Pb uptake and translocation, promoting nutrient uptake, and improving the diversity and stability of the soil bacteria community. Under Pb stress, the relative abundances of metal-resistance bacteria significantly increased, such as the abundance of Bacteroidetes in females and the abundances of Actinobacteria, Firmicutes, and Planctomycetes in males. In brief, the males under biochar addition exhibited promising potential as candidates for phytoremediation of Pb-contaminated soil. This study provides new insights into mechanisms underlying sexually differential responses to Pb stress in the presence of biochar amendment.


Asunto(s)
Populus , Salicaceae , Contaminantes del Suelo , Animales , Biodegradación Ambiental , Ecosistema , Plomo/toxicidad , Suelo , Masculino , Femenino
4.
Biochem Biophys Res Commun ; 605: 134-140, 2022 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-35325655

RESUMEN

Obesity and associated complications are becoming a pandemic. Inhibiting fatty acid synthesis and elongation is an important intervention for the treatment of obesity. Despite intensive investigations, many potential therapeutic targets have yet to be discovered. In this study, decreased expression of Hacd2 (a newly found enzyme in fatty acid elongation) was found in HFD induced mice and loss of Hacd2 expression in the liver protected mice against HFD induced obesity as well as associated fatty liver disease and diabetes. Additionally, further study indicated that hepatic HACD2 deficiency increased energy expenditure by upregulating the transcription of thermogenic programming genes. Our results suggest that HACD2 may be a promising therapeutic target for the management of obesity and associated metabolic diseases.


Asunto(s)
Intolerancia a la Glucosa , Resistencia a la Insulina , Animales , Coenzima A/metabolismo , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos/metabolismo , Intolerancia a la Glucosa/genética , Hidroliasas/metabolismo , Resistencia a la Insulina/fisiología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/metabolismo
5.
Environ Res ; 203: 111894, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34418448

RESUMEN

The Tibetan Plateau (TP) has a variety of vegetation types that range from alpine tundra to tropic evergreen forest, which play an important role in the global carbon (C) cycle and is extremely vulnerable to climate change. The vegetation C uptake is crucial to the ecosystem C sequestration. Moreover, net reduction in vegetation C uptake (NRVCU) will strongly affect the C balance of terrestrial ecosystem. Until now, there is limited knowledge on the recovery process of vegetation net C uptake and the spatial-temporal patterns of NRVCU after the disturbance that caused by climate change and human activities. Here, we used the MODIS-derived net primary production to characterize the spatial-temporal patterns of NRVCU. We further explored the influence factors of the net reduction rate in vegetation C uptake (NRRVCU) and recovery processes of vegetation net C uptake across a unique gradient zone on the TP. Results showed that the total net reduction amount of vegetation C uptake gradually decreased from 2000 to 2015 on the TP (Slope = -0.002, P < 0.05). Specifically, an increasing gradient zone of multi-year average of net reduction rate in vegetation carbon uptake (MYANRRVCU) from east to west was observed. In addition, we found that the recovery of vegetation net C uptake after the disturbance caused by climate change and anthropogenic disturbance in the gradient zone were primarily dominated by precipitation and temperature. The findings revealed that the effects of climate change on MYANRRVCU and vegetation net C uptake recovery differed significantly across geographical space and vegetation types. Our results highlight that the biogeographic characteristics of the TP should be considered for combating future climate change.


Asunto(s)
Cambio Climático , Ecosistema , Efectos Antropogénicos , Carbono , Humanos , Temperatura , Tibet
6.
Nutr Cancer ; 72(4): 696-707, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31352802

RESUMEN

Kudingcha is implicated in alleviating metabolic disorders in traditional Chinese medicine. However, the role of Kudingcha, one of the Ligustrum robustum species, in metabolic regulations and its antitumor activity in triple-negative breast cancer (TNBC) remains to be determined. Two breast cancer cell lines and immunocompetent and immunodeficient mice were used to evaluate the therapeutic effects of Kudingcha treatment. The production of reactive oxygen species (ROS) and glucose uptake were examined by flow cytometry. Metabolic shift was examined by metabonomics and western blot analysis. In this study, we found that aqueous extract of Kudingcha dose dependently inhibited cell growth and induced apoptosis in vitro and in vivo. Moreover, Kudingcha supplementation significantly reduced cancer metastasis. Kudingcha significantly inhibited glycolysis and glutamine metabolism. In addition, we demonstrated that the antitumor effects of Kudingcha were dependent on ROS production, which was increased by ß-oxidation and oxidative phosphorylation. These findings provide a novel potential benefit of Kudingcha from targeting the cancer metabolism.


Asunto(s)
Apoptosis/efectos de los fármacos , Ligustrum , Metástasis de la Neoplasia/prevención & control , Extractos Vegetales/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Bebidas , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal , Femenino , Glucólisis/efectos de los fármacos , Humanos , Ratones , Especies Reactivas de Oxígeno/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Biochem Biophys Res Commun ; 512(2): 196-201, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-30879764

RESUMEN

G-protein coupled receptor 120 (GPR120 or FFAR4) functions as a receptor for free fatty acids and plays a critical role in lipid metabolism. Studies have shown a close relationship between GDM and lipid metabolism disorders, whether GPR120 participates in the metabolic regulation of GDM remains unclear. In this study, 29 women with GDM and 33 normal pregnant women were enrolled. Lipid profiles were determined by lipidomics, expression of GPR120 and FGF21 was measured in the white blood cells, and regulation of FGF21 by GPR120 was investigated in THP-1 cells as well as human peripheral blood monocytes. Lipidomics reveal altered lipid metabolism in patients with GDM. The expression of both GPR120 and FGF21 is significantly higher in the GDM than in the control at the 32nd and 37th weeks of pregnancy, but the differences disappear by the 2nd day post-delivery. Generally positive correlations are found between the total amount of lipids and expression levels of GPR120 and FGF21 in GDM patients. FGF21 expression is induced by GPR120 activation in THP-1 cells and WBCs. GPR120 may act as a metabolic regulator, through the induction of FGF21, to control lipid metabolism, and GDM patients may manifest a GPR120 insensitivity.


Asunto(s)
Diabetes Gestacional/metabolismo , Metabolismo de los Lípidos , Receptores Acoplados a Proteínas G/metabolismo , Adulto , Línea Celular , Células Cultivadas , Diabetes Gestacional/genética , Femenino , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Humanos , Leucocitos/metabolismo , Embarazo , ARN Mensajero/análisis , ARN Mensajero/genética , Receptores Acoplados a Proteínas G/genética , Regulación hacia Arriba , Adulto Joven
8.
Cell Tissue Bank ; 18(1): 53-59, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28138805

RESUMEN

This study aimed to determine the efficacy and safety of human umbilical cord-derived mesenchymal stem cell (HUC-MSC) transplantation for treating elderly vascular dementia (VaD). Ten VaD patients (average age, 73.88 years old) were treated. HUC-MSCs were isolated, cultured, stem cell-marked, and qualified and administered as a 3-course intravenous infusion to these patients. The Mini-Mental State Exam (MMSE) and the Activities of Daily Living Index (Barthel Index scoring system) were used to assess the cognitive function and daily living activity improvements in these patients before transplantation (T0), 3 months after transplantation (T1), and 6 months after transplantation (T2). The MMSE and Barthel Index scores were 15.80 ± 5.49 and 42.00 ± 9.33 points at T0, respectively, and were significantly different when compared with those at T1 (19.20 ± 6.39 and 49.20 ± 10.86 points, respectively, P < 0.05), whereas there was no difference when compared with those at T2 (14.00 ± 6.55 and 40.70 ± 10.37 points, respectively, P > 0.05). HUC-MSC transplantation was safe and feasible for VaD and improved early cognitive functions and daily living activities in VaD patients to a certain extent, thus improving patients' quality of life.


Asunto(s)
Demencia Vascular/terapia , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Cordón Umbilical/citología , Anciano , Separación Celular , Células Cultivadas , Cognición , Demencia Vascular/fisiopatología , Femenino , Humanos , Masculino , Trasplante de Células Madre Mesenquimatosas/métodos , Persona de Mediana Edad , Calidad de Vida
9.
Stat Med ; 34(4): 664-84, 2015 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-25393617

RESUMEN

Instrumental variable (IV) analysis has been widely used in economics, epidemiology, and other fields to estimate the causal effects of covariates on outcomes, in the presence of unobserved confounders and/or measurement errors in covariates. However, IV methods for time-to-event outcome with censored data remain underdeveloped. This paper proposes a Bayesian approach for IV analysis with censored time-to-event outcome by using a two-stage linear model. A Markov chain Monte Carlo sampling method is developed for parameter estimation for both normal and non-normal linear models with elliptically contoured error distributions. The performance of our method is examined by simulation studies. Our method largely reduces bias and greatly improves coverage probability of the estimated causal effect, compared with the method that ignores the unobserved confounders and measurement errors. We illustrate our method on the Women's Health Initiative Observational Study and the Atherosclerosis Risk in Communities Study.


Asunto(s)
Análisis de Varianza , Teorema de Bayes , Bioestadística/métodos , Aterosclerosis/etiología , Simulación por Computador , Femenino , Humanos , Modelos Lineales , Masculino , Cadenas de Markov , Método de Montecarlo , Estudios Observacionales como Asunto/estadística & datos numéricos , Factores de Riesgo , Salud de la Mujer/estadística & datos numéricos
10.
Artículo en Inglés | MEDLINE | ID: mdl-38393850

RESUMEN

In the paper, we present an integrated flow cytometer with a 2D array of magnetic sensors based on dual-frequency oscillators in a 65-nm CMOS process, with the chip packaged with microfluidic controls. The sensor architecture and the presented array signal processing allows uninhibited flow of the sample for high throughput without the need for hydrodynamic focusing to a single sensor. To overcome the challenge of sensitivity and specificity that comes as a trade off with high throughout, we perform two levels of signal processing. First, utilizing the fact that a magnetically tagged cell is expected to excite sequentially an array of sensors in a time-delayed fashion, we perform inter-site cross-correlation of the sensor spectrograms that allows us to suppress the probability of false detection drastically, allowing theoretical sensitivity reaching towards sub-ppM levels that is needed for rare cell or circulating tumor cell detection. In addition, we implement two distinct methods to suppress correlated low frequency drifts of singular sensors-one with an on-chip sensor reference and one that utilizes the frequency dependence of the susceptibility of super-paramagnetic magnetic beads that we deploy as tags. We demonstrate these techniques on a 7×7 sensor array in 65 nm CMOS technology packaged with microfluidics with magnetically tagged dielectric particles and cultu lymphoma cancer cells.

11.
Nutr Cancer ; 65(8): 1232-44, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24127740

RESUMEN

Ellagic acid is a polyphenolic phytochemical present in many fruits and nuts with anticancer properties demonstrated in experimental tumor studies. Embelin is a benzoquinone phytochemical isolated from the Japanese herb Ardisiae Japonicae and has been shown to induce apoptosis in cancer cells. We found that ellagic acid and embelin each dose-dependently increased apoptosis and inhibited proliferation in human pancreatic cancer cells, MIA PaCa-2 and HPAF-II cells, and in pancreatic stellate cells, which are progenitors of pancreatic cancer desmoplasia. In each of these cell types, combinations of ellagic acid and embelin at low micromolar concentrations (0.5-3 µM) induced synergistic increases in apoptosis and decreases in proliferation. Ellagic acid decreased NF-κB transcriptional activity, whereas embelin decreased STAT-3 phosphorylation and protein expression of its downstream target survivin in cancer cells. In vivo dietary ellagic acid alone or in combination with embelin decreased tumor size and tumor cellularity in a subcutaneous xenograft mouse model of pancreatic cancer. These results show that ellagic acid and embelin interact with divergent intracellular signaling pathways resulting in augmentation of apoptosis and inhibition of proliferation at low micromolar concentrations for the key cellular components of pancreatic adenocarcinoma.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Benzoquinonas/farmacología , Ácido Elágico/farmacología , Neoplasias Pancreáticas/metabolismo , Células Estrelladas Pancreáticas/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Humanos , Masculino , Ratones , Ratones Desnudos , FN-kappa B/genética , FN-kappa B/metabolismo , Fosforilación , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Neoplasias Pancreáticas
12.
Microbiol Res ; 273: 127409, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37186995

RESUMEN

Debris-covered glaciers (DCGs) are globally distributed and thought to contain greater microbial diversity than clean surface continental glaciers, but the ecological characteristics of microbial communities on the surface of DCGs have remained underexplored. Here, we investigated bacterial and fungal diversity and co-occurrence networks on the supraglacial debris habitat of two DCGs (Hailuogou and Dagongba Glaciers) in the southeastern Tibetan Plateau. We found that the supraglacial debris harbored abundant microbes with Proteobacteria occupying more than half (51.5%) of the total bacteria operational taxonomic units. The composition, diversity, and co-occurrence networks of both bacterial and fungal communities in the debris were significantly different between Hailuogou Glacier and Dagongba Glacier even though the glaciers are geographically adjacent within the same mountain range. Bacteria were more diverse in the debris of the Dagongba Glacier, where a lower surface velocity and thicker debris layer allowed the supraglacial debris to continuously weather and accumulate nutrients. Fungi were more diverse in the debris of the Hailuogou Glacier, which experiences a wetter monsoonal climate, is richer in calcium, has greater debris instability, and greater ice velocity than the Dagongba Glacier. These factors may provide ideal conditions for the dispersal and propagation of fungi spores on the Hailuogou Glacier. In addition, we found an obvious gradient of bacterial diversity along the supraglacial debris transect on the Hailuogou Glacier. Bacterial diversity was lower where debris cover was thin and scattered and became more diverse near the glacial terminus in thick, slow-moving debris. No such increasing bacterial pattern was detected on the Dagongba Glacier, which implies a positive relationship of debris age, thickness, and weathering on bacterial diversity. Additionally, a highly connected bacterial co-occurrence network with low modularity was found in the debris of the Hailuogou Glacier. In contrast, debris from the Dagongba Glacier exhibited less connected but more modularized co-occurrence networks of both bacterial and fungal communities. These findings indicate that less disturbed supraglacial debris conditions are crucial for microbes to form stable communities on DCGs.


Asunto(s)
Microbiota , Micobioma , Cubierta de Hielo/microbiología , Tibet , Bacterias/genética
13.
Sci Total Environ ; 880: 163393, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37037383

RESUMEN

Biochar is a renewable, carbon-neutral energy source that can replace traditional fossil fuels for iron and steel production, so it is of great significance to reduce carbon emissions and reduce pollution. In this paper, the reaction characteristics and kinetics between biomass (bamboo powder) pyrolysis gas, biochar, and iron ore powder are studied by a thermogravimetric analyzer (TG). Comparing the samples with four different C/O ratios (C/O = 0.375, 0.5, 1, 3), it is found that the sample with C/O = 1 can completely reduce hematite. The mass loss process is divided into the following four stages: de-crystal water, hematite to magnetite, magnetite to wustite, and wustite to metallic iron. Among them, the latter three stages are following the kinetic model of random nucleation (n = 1, 2) and three-dimensional diffusion, and the activation energy of the three stages increases and then decreases. Through scanning electron microscopy (SEM), the surface of hematite particles changed from relatively flat to porous and finally the reduced metal iron aggregated, and connected into large pieces. By using online Thermogravimetry-Fourier Transform Infrared Reflection (TG-FTIR), when the reduction temperature is lower than 700 °C, biochar plays a leading role. On the contrary, the CO produced by biochar gasification plays a leading role.

14.
Radiother Oncol ; 185: 109669, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37054987

RESUMEN

PURPOSE: To assess the safety and efficacy of AN0025 in combination with preoperative radiotherapy and chemotherapy in either short course (SCRT) or long course radiotherapy (LCRT) settings for those with locally advanced rectal cancer. PATIENTS AND METHODS: Twenty-eight subjects with locally advanced rectal cancer participated in this multicenter, open-label, Phase Ib trial. Enrolled subjects received either 250 mg or 500 mg of AN0025 once daily for 10 weeks with either LCRT or SCRT with chemotherapy (7 subjects/group). Participants were assessed for safety/efficacy starting from the first dose of study drug administration and were followed for 2 years. RESULTS: No treatment-emergent adverse or serious adverse events meeting dose-limiting criteria were observed, with only 3 subjects discontinuing AN0025 treatment due to adverse events. Twenty-five of 28 subjects completed 10 weeks of AN0025 and adjuvant therapy and were evaluated for efficacy. Overall, 36.0% of subjects (9/25 subjects) achieved a pathological complete response or a complete clinical response, including 26.7% of subjects (4/15 subjects who underwent surgery) who achieved a pathological complete response. A total of 65.4% of subjects had magnetic resonance imaging-confirmed down-staging ≤ stage 3 following completion of treatment. With a median follow-up of 30 months. The 12-month disease-free survival and overall survival were 77.5% (95% confidence interval [CI]: 56.6, 89.2) and 96.3% (95% CI: 76.5, 99.5), respectively. CONCLUSIONS: Treatment with AN0025 administered for 10 weeks along with preoperative SCRT or LCRT did not appear to worsen the toxicity in subjects with locally advanced rectal cancer, was well-tolerated and showed promise in inducing both a pathological and complete clinical response. These findings suggest its activity deserves further investigation in larger clinical trials.


Asunto(s)
Dinoprostona , Neoplasias del Recto , Humanos , Dinoprostona/uso terapéutico , Terapia Neoadyuvante/efectos adversos , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/patología , Recto/patología , Supervivencia sin Enfermedad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estadificación de Neoplasias
15.
Am J Pathol ; 178(3): 1340-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21356384

RESUMEN

Epithelial neutrophil-activating peptide-78 (CXCL5), a member of the CXC chemokine family, has been shown to be involved in angiogenesis, tumor growth, and metastasis. The objective of this study was to determine the relationship between CXCL5 expression and tumor progression in human pancreatic cancer and to elucidate the mechanism underlying CXCL5-mediated tumor angiogenesis and cancer growth. We report herein that CXCL5 is overexpressed in human pancreatic cancer compared with paired normal pancreas tissue. Overexpression of CXCL5 is significantly correlated with poorer tumor differentiation, advanced clinical stage, and shorter patient survival. Patients with pancreatic cancer and CXCL5 overexpression who underwent resection of cancer had a mean survival time 25.5 months shorter than that of patients who did not overexpress CXCL5. Blockade of CXCL5 or its receptor CXCR2 by small-interfering RNA knockdown or antibody neutralization attenuated human pancreatic cancer growth in a nude mouse model. Finally, we demonstrated that CXCL5 mediates pancreatic cancer-derived angiogenesis through activation of several signaling pathways, including protein kinase B (Akt), extracellular signal-regulated kinase (ERK), and signal transducer and activator of transcription (STAT) in human endothelial cells. These data suggest that CXCL5 is an important mediator of tumor-derived angiogenesis and that it may serve as a survival factor for pancreatic cancer. Blockade of either CXCL5 or CXCR2 may be a critical adjunct antiangiogenic therapy against pancreatic cancer.


Asunto(s)
Quimiocina CXCL5/metabolismo , Neoplasias Pancreáticas/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular , Quimiocina CXCL5/genética , Progresión de la Enfermedad , Células Endoteliales/enzimología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Desnudos , Neovascularización Patológica/metabolismo , Pruebas de Neutralización , Neoplasias Pancreáticas/irrigación sanguínea , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Interleucina-8B/metabolismo , Análisis de Supervivencia , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Front Plant Sci ; 13: 1036369, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36325540

RESUMEN

A change in precipitation can profoundly change the structure of soil microbial communities, especially in arid and semi-arid areas which are limited by moisture conditions. Therefore, it is crucial to explore how soil bacterial community composition and diversity will respond to variation in precipitation. Here we conducted a precipitation control experiment to simulate precipitation change by reducing and increasing rainfall by 25%, 50%, and 75% in the alpine grasslands of northern Tibet. The composition, diversity, and species interaction network of soil microbial community were studied by high-throughput sequencing, and the relationship between microbial community species and soil environmental factors was analyzed. Our results showed that Proteobacteria (45%-52%) and Actinobacteria (37%-45%) were the dominant bacteria in the soil. The alpha diversity index based on Shannon, Chao1, and Simpson indices revealed that precipitation change had no significant effect on richness and evenness of soil microbial communities. Non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) showed that a clear separation of soil microbial communities between D2(-50%),D3(-75%) and W2(+50%), W3(+75%) treatments. The microbial interaction network indicated that the water-increasing treatment group had closer connections, and Proteobacteria and Actinomycetes were the core species. Furthermore, there was a stronger positive correlation between species in the water-reducing treatment group, the contribution of Proteobacteria decreased significantly, the role of connecting hub decreased, and Actinomycetes became the most important core microbial species. In addition, soil water content (SWC) and available phosphorus (AP) were closely related to the variations in soil microbial compositions. The findings of this study provide a theoretical basis for the driving mechanism of global climate change on soil microbial community and grassland ecosystem in alpine grassland.

17.
Front Microbiol ; 13: 931795, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35935214

RESUMEN

As the link between plants and soils, rhizosphere soil microorganisms play an important role in the element cycle. This study aimed to understand the response of the rhizosphere soil microbial community structure and interaction network to grassland utilization in the alpine steppe of the northern Tibet Plateau. High-throughput sequencing was employed to study the composition, diversity, and species interaction network of rhizosphere soil microbial communities under grazing, mowing, and enclosing treatments. Proteobacteria (47.19%) and Actinobacteria (42.20%) were the dominant bacteria in the rhizosphere soil. There was no significant difference in relative abundance among rhizosphere soil microorganisms at phylum and genus levels, but differences were found in Chlorobi, Ignavibacteriae, and Micromonospora. The alpha diversity index based on Shannon, Chao1, and Simpson indices revealed that except for a significant difference in the Shannon index of the Artemisia nanschanica group, the richness and evenness of rhizosphere soil microbial communities among all groups were similar. Non-metric multidimensional scaling (NMDS) and multi-response permutation procedure (MRPP) analyses showed that the inter-group differences of three plants (Stipa purpurea, Carex moorcroftii, and Artemisia nanschanica) were greater than the differences within the groups; however, only the inter-group difference with the Stipa purpurea group was significant. The microbial interaction network showed that the network complexity of the Artemisia nanschanica group and the enclosing treatment, which were not easily influenced by external factors, were higher than those of the other groups and treatments; this again demonstrated that Proteobacteria and Actinobacteria were the network core microbial species in alpine steppe of the northern Tibet Plateau and were crucial for maintaining stability of the microbial communities. Findings from this study provide a theoretical basis for the restoration of degraded alpine grassland and the development of microbial functions.

18.
Adv Sci (Weinh) ; 9(28): e2105016, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35896946

RESUMEN

Origami is the art of paper folding that allows a single flat piece of paper to assume different 3D shapes depending on the fold patterns and the sequence of folding. Using the principles of origami along with computation imaging technique the authors demonstrate a versatile shape-morphing microwave imaging array with reconfigurable field-of-view and scene-adaptive imaging capability. Microwave/millimeter-wave based array imaging systems are expected to be the workhorse for sensory perception of future autonomous intelligent systems. The imaging capability of a planar array-based systems operating in complex scattering conditions have limited field-of-view and lack the ability to adaptively reconfigure resolution. To overcome this, here, deviations from planarity and isometry are allowed, and a shape-morphing computational imaging system is demonstrated. Implemented on a reconfigurable Waterbomb origami surface with 22 active metasurface panels that radiate near-orthogonal modes across 17-27 GHz, capability to image complex 3D objects in full details minimizing the effects of specular reflections in diffraction-limited sparse imaging with scene adaptability, reconfigurable cross-range resolution, and field-of-view is demonstrated. Such electromagnetic origami surfaces, through simultaneous surface shape-morphing ability (potentially with shape-shifting electronic materials) and electromagnetic field programmability, opens up new avenues for intelligent and robust sensing and imaging systems for a wide range of applications.


Asunto(s)
Imágenes de Microonda , Diagnóstico por Imagen , Microondas
19.
Clin Chem ; 57(2): 317-25, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21149504

RESUMEN

BACKGROUND: Circulating concentrations of high-sensitivity C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) have been associated with an increased risk of diabetes. METHODS: To examine the roles of genetic variation in the genes encoding CRP, TNF- α, and IL-6 in the development of diabetes, we conducted a prospective case-control study nested within the Women's Health Initiative Observational Study. We followed 82 069 postmenopausal women (50-79 years of age) with no history of diabetes for incident diabetes for a mean follow-up of 5.5 years. We identified 1584 cases and matched them with 2198 controls with respect to age, ethnicity, clinical center, time of blood draw, and length of follow-up. We genotyped 13 haplotype-tagging single-nucleotide polymorphisms (tSNPs) across 2.3 kb of the CRP (C-reactive protein, pentraxin-related) gene, 16 tSNPs across 2.8 kb of the TNF (tumor necrosis factor) gene, and 14 tSNPs across 4.8 kb of the IL6 [interleukin 6 (interferon, beta 2)] gene. Plasma concentrations of TNF-α receptor 2 (TNF-α-R2) and IL-6 were measured. RESULTS: After adjusting for matching factors, confounding variables, and multiple comparisons, we found 8 variants in the TNF gene to be associated with plasma TNF-α-R2 concentrations in white women (q < 0.05). After adjusting for multiple comparisons (q > 0.05), we found no association of any IL6 gene variant with plasma IL-6 concentration, nor did we find any significant associations between any SNPs among these 3 genes and diabetes risk (q > 0.05). CONCLUSIONS: We found modest associations between TNF variants and circulating concentrations of TNF-α-R2. Common variants of the CRP, TNF, and IL6 genes were not significantly associated with risk of clinical diabetes in postmenopausal women.


Asunto(s)
Proteína C-Reactiva/genética , Diabetes Mellitus/genética , Interleucina-6/genética , Factor de Necrosis Tumoral alfa/genética , Estudios de Casos y Controles , Diabetes Mellitus/etnología , Femenino , Frecuencia de los Genes , Humanos , Interleucina-6/sangre , Polimorfismo de Nucleótido Simple , Receptores del Factor de Necrosis Tumoral/sangre , Medición de Riesgo
20.
Sci Total Environ ; 750: 142306, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33182203

RESUMEN

The decomposition of plant litter is a key link in global C budgets and provides strong feedback to changes in climate and biogeochemical cycles. However, the combined effects of global warming and plant litter quality on the rate of plant litter decomposition and nutrient dynamics in alpine ecosystems are still poorly understood. We conducted a warming experiment to investigate the effects of litter quality and temperature on decomposition rates and variations in nutrients of four common herbaceous plants (low-quality litter species Stipa purpurea and Carex moorcroftii and high-quality litter species Astragalus confertus and Leontopodium nanum) during 2011-2016. During the initial stages of decomposition, warming had no significant effect on the mass loss of plant litter for low-quality litter species, but in the later stages of decomposition, it had a negative effect on the mass loss across all species (P < 0.05). Litter quality was the best predictor of N and P release/immobilisation during the decomposition of aboveground plant litter. Low-quality litter had the highest immobilisation of N at about 80% of the initial remaining mass; nutrients were then released in the following stages of decomposition. However, the fraction of initial P decreased with the mass remaining during the initial and later phases of decomposition, but a short period of P immobilisation occurred in the middle phase of decomposition. For high-quality litter, the fraction of initial N and P decreased with the mass remaining during the whole decomposition process. Warming had a marginal influence on the N and P dynamics throughout the decomposition process. Our study showed that the decay of plant litter was strongly suppressed by warming climate and that the N and P dynamics on the investigated Tibetan grassland were mainly regulated by litter quality, providing valuable insights into the biogeochemical cycles of nutrients in alpine ecosystems.


Asunto(s)
Ecosistema , Pradera , Hojas de la Planta , Plantas , Poaceae , Tibet
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