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1.
BMC Plant Biol ; 22(1): 337, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35831803

RESUMEN

BACKGROUND: Grazing disturbance plays an important role in the desert steppe ecosystem in Inner Mongolia, China. Previous studies found that grazing affected the spatial distribution of species in a community, and showed patchiness characteristics of species under different grazing treatments. Artemisia frigida is the dominant species and semi-shrub in desert steppe, and whether grazing interference will affect the spatial distribution of A. frigida is studied. In this study, geo-statistical methods were mainly used to study the spatial distribution characteristics of A. frigida population in desert steppe of Inner Mongolia at two scales (quadrat size 2.5 m × 2.5 m, 5 m × 5 m) and four stocking rates (control, CK, 0 sheep·ha-1·month-1; light grazing, LG, 0.15 sheep·ha-1·month-1, moderate grazing, MG, 0.30 sheep·ha-1·month-1, heavy grazing, HG, 0.45 sheep·ha-1·month-1). RESULTS: The results showed that the spatial distribution of A. frigida tended to be simplified with the increase of stocking rate, and tended to be banded with increased spatial scale. The density and height of A. frigida increased with increasing scale. With increased stocking rate, the density of A. frigida population decreased linearly, while its height decreased in a step-wise fashion. The spatial distribution of A. frigida was mainly affected by structural factors at different scales and stocking rate. The density of A. frigida was more sensitive to change in stocking rate, and the patchiness distribution of A. frigida was more obvious with increase in scale. CONCLUSIONS: Stocking rate has a strong regulatory effect on the spatial pattern of A. frigida population in the desert steppe. Heavy grazing reduced the spatial heterogeneity of A. frigida in the desert steppe. The smaller dominant populations are unfavourable for its survival in heavy grazing condition, and affects the stability and productivity of the grassland ecosystem.


Asunto(s)
Artemisia , Ecosistema , Animales , China , Poaceae , Ovinos , Suelo/química
2.
Fish Shellfish Immunol ; 125: 212-219, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35569778

RESUMEN

Normal dissolved oxygen in water is essential for maintaining the physiological functions of fish, but environmental pollution, such as eutrophication can lead to a decrease in oxygen content in water. How this reduction of dissolved oxygen in water affects the immune functions of fish and the potential regulatory mechanisms have not been thoroughly elucidated. In this study, we made full use of the aquatic model animal zebrafish to explore this question. In a model of LPS-induced inflammation, we found that hypoxia induced by infusing nitrogen into water increased the expression of pro-inflammatory cytokines, such as il-1ß, il-6, and il-8. In vivo imaging also showed that hypoxia significantly increased neutrophil migration to the site of caudal fin injury in the transgenic line. Subsequently, we found that the phosphorylation level of ERK protein was significantly activated upon hypoxia and proved the roles of ERK signaling in the expression of pro-inflammatory cytokines and neutrophil migration in zebrafish. This study indicated that reduced water oxygen significantly increases the inflammatory response of the zebrafish.


Asunto(s)
Citocinas , Pez Cebra , Animales , Citocinas/genética , Citocinas/metabolismo , Hipoxia/genética , Inflamación/inducido químicamente , Inflamación/genética , Neutrófilos , Oxígeno/metabolismo , Agua , Pez Cebra/genética , Pez Cebra/metabolismo
3.
BMC Cardiovasc Disord ; 20(1): 211, 2020 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-32375652

RESUMEN

BACKGROUND: Lipid infiltration and inflammatory response run through the occurrence of atherosclerosis. Differentiation into macrophages and foam cell formation are the key steps of AS. Aim of this study was that the differential gene expression between foam cells and macrophages was analyzed to search the key links of foam cell generation, so as to explore the pathogenesis of atherosclerosis and provide targets for the early screening and prevention of coronary artery disease (CAD). METHODS: The gene expression profiles of GSE9874 were downloaded from Gene Expression Omnibus (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE9874) on GPL96 [HG-U133A] Affymetrix Human Genome U133. A total of 22,383 genes were analyzed for differentially expression genes (DEGs) by Bayes package. GO enrichment analysis and KEGG pathway analysis for DEGs were performed using KOBAS 3.0 software (Peking University, Beijing, China). STRING software (STRING 10.0; European Molecular Biology Laboratory, Heidelberg, Germany) was used to analyze the protein-protein interaction (PPI) of DEGs. RESULTS: A total of 167 DEGs between macrophages and foam cells were identified. Compared with macrophages, 102 genes were significantly upregulated and 65 genes were significantly downregulated (P < 0.01, fold-change > 1) in foam cells. DEGs were mainly enrich in 'sterol biosynthetic and metabolic process', 'cholesterol metabolic and biosynthetic process' by GO enrichment analysis. The results of KEGG pathway analysis showed all differential genes are involved in biological processes through 143 KEGG pathways. A PPI network of the DEGs was constructed and 10 outstanding genes of the PPI network was identified by using Cytoscape, which include HMGCR, SREBF2, LDLR, HMGCS1, FDFT1, LPL, DHCR24, SQLE, ABCA1 and FDPS. CONCLUSION: Lipid metabolism related genes and molecular pathways were the key to the transformation of macrophages into foam cells. Therefore, lipid metabolism disorder is the key to turn macrophages into foam cells, which plays a major role in CAD.


Asunto(s)
Aterosclerosis/genética , Células Espumosas/metabolismo , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Análisis de Secuencia por Matrices de Oligonucleótidos , Mapas de Interacción de Proteínas , Transducción de Señal/genética , Transcriptoma , Aterosclerosis/metabolismo , Aterosclerosis/patología , Biomarcadores/metabolismo , Estudios de Casos y Controles , Bases de Datos Genéticas , Células Espumosas/patología , Humanos
4.
J Environ Sci (China) ; 66: 20-30, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29628088

RESUMEN

Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen (N) dynamics and nitrous oxide (N2O) emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N2O emissions by field experiments in Hulunber in northern China. Soil (0-10cm), nitrate (NO3-), ammonium (NH4+), and microbial N were measured in plots in a temperate steppe (Leymus chinensis grassland) and two managed grasslands (Medicago sativa and Bromus inermis grasslands) in 2011 and 2012. The results showed conversion of L. chinensis grassland to M. sativa or B. inermis grasslands decreased concentrations of NO3--N, but did not change NH4+-N. Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M. sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa (i.e., a legume grass) increased N2O emissions by 26.2%, while the conversion to the B. inermis (i.e., a non-legume grass) reduced N2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO3--N and NH4+-N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N2O emissions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Pradera , Dióxido de Nitrógeno/análisis , China , Nitrificación , Ciclo del Nitrógeno , Estaciones del Año , Suelo
5.
Can J Physiol Pharmacol ; 95(5): 610-619, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28177676

RESUMEN

Antler velvet polypeptide (VAP) is a prominent bioactive component of antler velvet. Whereas uncharacterized crude extracts have typically been used in pharmacological studies, in this study, the velvet polypeptide was isolated and purified by acid water extraction, ethanol precipitation, ammonium sulfate fractionation and precipitation, and chromatography, progressively. Human umbilical vein endothelial cells (HUVECs) were induced with H2O2 followed purified polypeptide treatment. Cell viability was evaluated by MTT assay. The apoptosis of cells was detected by fluorescence microscopy and flow cytometry. A cell analyzer was used to measure the mitochondrial membrane potential. The intracellular reactive oxygen species (ROS) levels were determined by flow cytometry. Oxidative stress related biochemical parameters were detected, and the expression of apoptosis-related proteins was examined by Western blot analysis. The results indicated that a 7.0 kDa polypeptide (VAP II) was isolated from antler velvet. VAP II enhanced cell viability, decreased cell apoptosis, reversed depolarization of mitochondrial membrane potential, decreased ROS levels, inhibited oxidative stress, and regulated the downstream signaling apoptotic cascade expression caused by H2O2. The protective effects of VAP II on HUVECs suggests a potential strategy for the treatment of cardiovascular disease.


Asunto(s)
Cuernos de Venado/química , Citoprotección/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Peróxido de Hidrógeno/farmacología , Péptidos/farmacología , Animales , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/citología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
6.
Zhongguo Zhong Yao Za Zhi ; 42(15): 3026-3030, 2017 Aug.
Artículo en Zh | MEDLINE | ID: mdl-29139274

RESUMEN

To investigate the effect of dihydroartemisinin on apoptosis of human pancreatic cancer cell line JF-305 and the role of reactive oxygen species(ROS) in the apoptosis of JF-305 cells induced by dihydroartemisinin. MTT assays were used to detect effect of different concentrations of dihydroartemisinin on cells proliferation of JF-305 lines. Cell cycle was detected by flow cytometry, and the apoptotic morphology was observed by Hoechst 333258 fluorescence staining. Annexin V fluorescence staining was used to detect the apoptosis changes of JF-305 cells, while DCFH-DA was used to detect the changes of ROS during apoptosis process. Western blot was used to detect the protein expression changes of Bax, Bcl-2, Cleaved caspase-3, Cleaved caspase-9 and Cyto C. As compared with the control group, the JF-305 cells proliferation was inhibited significantly(P<0.05) after treatment with different concentrations of dihydroartemisimin for 48 h; cell cycle was blocked in the G2/M phase; apoptotic morphology of nuclear condensation, aggregation, and fragmentation was found, and the apoptosis ratio was increased(P<0.05). DCFH-DA detection showed that the cell ROS was increased significantly after dihydroartemisinin treatment(P<0.05). Western blot results showed that the expression of Bcl-2 protein was down-regulated; the expression of Bax protein was up-regulated; the ration of Bax/Bcl-2 was increased and the protein expression levels of Cleaved caspase-3, Cleaved caspase-9 and Cyto C were increased after dihydroartemisinin treatment. Therefore, dihydroartemisinin could induce apoptosis of JF-305 cells, and the possible mechanism may be related to the formation and increasing of ROS.


Asunto(s)
Apoptosis/efectos de los fármacos , Artemisininas/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Pancreáticas , Especies Reactivas de Oxígeno/metabolismo , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Citocromos c/metabolismo , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo
7.
Phys Chem Chem Phys ; 18(31): 21431-41, 2016 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-27424739

RESUMEN

The advances in cluster-assembled materials where clusters serve as building blocks have opened new opportunities to develop ever more sensitive gas sensors. Here, using density functional theory calculations, the structural and electronic properties of cluster-assembled nanowires based on M12N12 (M = Al and Ga) clusters and their application as gas sensors have been investigated. Our results show that the nanowires can be produced via the coalescence of stable M12N12 fullerene-like clusters. The M12N12-based nanowires have semiconducting electrical properties with direct energy gaps, and are particularly stable at room temperature for long enough to allow for their characterization and applications. Furthermore, we found that the CO, NO, and NO2 molecules are chemisorbed on the M12N12-based nanowires with reasonable adsorption energies and apparent charge transfer. The electronic properties of the M12N12-based nanowires present dramatic changes after the adsorption of the CO, NO, and NO2 molecules, especially their electric conductivity. However, the adsorption of NO2 on the Al12N12-based nanowire is too strong, indicating an impractical recovery time as NO2 sensors. In addition to this, due to reasonable adsorption energies, apparent charge transfer, change in the electric conductivity, and the short recovery time, the Al12N12-based nanowire should be a good CO and NO sensor with quick response as well as short recovery time, while the Ga12N12-based nanowire should be a promising gas sensor for CO, NO, and NO2 detection.

8.
Can J Physiol Pharmacol ; 94(8): 849-57, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27203380

RESUMEN

Microwaves may exert adverse biological effects on the cardiovascular system at the integrated system and cellular levels. However, the mechanism underlying such effects remains poorly understood. Here, we report a previously uncharacterized mechanism through which microwaves damage myocardial cells. Rats were treated with 2450 MHz microwave radiation at 50, 100, 150, or 200 mW/cm(2) for 6 min. Microwave treatment significantly enhanced the levels of various enzymes in serum. In addition, it increased the malondialdehyde content while decreasing the levels of antioxidative stress enzymes, activities of enzyme complexes I-IV, and ATP in myocardial tissues. Notably, irradiated myocardial cells exhibited structural damage and underwent apoptosis. Furthermore, Western blot analysis revealed significant changes in expression levels of proteins involved in oxidative stress regulation and apoptotic signaling pathways, indicating that microwave irradiation could induce myocardial cell apoptosis by interfering with oxidative stress and cardiac energy metabolism. Our findings provide useful insights into the mechanism of microwave-induced damage to the cardiovascular system.


Asunto(s)
Apoptosis/fisiología , Apoptosis/efectos de la radiación , Microondas/efectos adversos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/efectos de la radiación , Animales , Antioxidantes/metabolismo , Antioxidantes/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Masculino , Malondialdehído/metabolismo , Malondialdehído/efectos de la radiación , Miocitos Cardíacos/patología , Estrés Oxidativo/fisiología , Estrés Oxidativo/efectos de la radiación , Ratas , Ratas Wistar
9.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(4): 471-5, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-27323622

RESUMEN

OBJECTIVE: To explore the protection of high intensity microwave radiation on hypothalamo-pituitary-adrenal axis (HPAA) activity and hippocampal CA1 structure in rats and the protectiveeffect of Qindan Granule (QG) on radiation injured rats. METHODS: Totally 48 Wistar rats were randomlydivided into 8 groups, i.e., the normal control group, post-radiation day 1, 7, and 10 groups, 7 and 10days prevention groups, day 7 and 10 treatment groups, 6 in each group. Rats in prevention groups wererespectively administered with QG liquid (1 mL/100 g, 4. 75 g crude drugs) for 7 days and 10 days bygastrogavage and then microwave radiation. Then preventive effect for radiation injury was statisticallycalculated with the normal control group and the post-radiation day 1 group. Rats in treatment groupswere firstly irradiated, and then administered with QG liquid (1 mL/100 g, 4.75 g crude drugs). Finally preventive effect for radiation injury was statistically calculated with the normal control group, post-radiation day 7 and 10 groups. Contents of corticotrophin releasing hormone (CRH), beta endorphin (beta-EP), adrenocorticotropic hormone (ACTH), and heat shock protein 70 (HSP70) were detected. Morphological changes and structure of hippocampal CA1 region were observed under light microscope. RESULTS: Compared with the normal control group, contents of CRH and beta-EP significantly decreased in each radiation group. Serum contents of ACTH and beta-EP significantly increased in post-radiation day 1 and 7 groups (P < 0.05). Compared with radiation groups, beta-EP content in serum and pituitary significantly increased, and serum ACTH content significantly decreased in prevention groups (P < 0.05). Pituitary contents of CRH and beta-EP significantly increased in prevention groups. Serum contents of ACTH, beta-EP, and HSP70 were significantly lower in day 7 treatment group than post-radiation day 7 group (P < 0.05). Morphological results showed that pyramidal neurons in the hippocampal CA1 region arranged in disorder, with swollen cells, shrunken and condensed nucleus, dark dyeing cytoplasm, unclear structure. Vessels in partial regions were dilated with static blood; tissues were swollen and sparse. In prevention and treatment groups pathological damage of hippocampal CA1 region was obviously attenuated; neurons were arranged more regularly; swollen, pycnotic, or deleted neuron number were decreased; vascular dilatation and congestion was lessened. CONCLUSION: QG could affect HPAA function and activity of high intensity microwave radiated rats, showing certain preventive and therapeutic effects of microwave radiated rats by adjusting synthesis and release of partial bioactive peptides and hormones in HPAA, improving pathological injury in hippocampal CA1 region.


Asunto(s)
Región CA1 Hipocampal/efectos de los fármacos , Región CA1 Hipocampal/patología , Medicamentos Herbarios Chinos/farmacología , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Microondas/efectos adversos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Hormona Adrenocorticotrópica/sangre , Animales , Región CA1 Hipocampal/efectos de la radiación , Hormona Liberadora de Corticotropina/metabolismo , Proteínas HSP70 de Choque Térmico/sangre , Sistema Hipotálamo-Hipofisario/efectos de la radiación , Sistema Hipófiso-Suprarrenal/efectos de la radiación , Distribución Aleatoria , Ratas , Ratas Wistar , betaendorfina/sangre , betaendorfina/metabolismo
10.
Can J Physiol Pharmacol ; 92(4): 324-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24708215

RESUMEN

New therapeutic approaches are needed to improve the survival rate from pancreatic cancer, one of the most lethal human malignancies. In this study, JF305 cells were treated with microwaves at doses of 2.5, 5.0, 10.0, 15.0, and 20.0 mW/cm(2) for 20 min. The inhibition of JF305 cell proliferation was tested using the MTT assay. Apoptotic cells were detected with Hoechst 33258 staining and a Nucleo-Counter NC-3000. The expression of apoptosis-related proteins was examined with Western blot. The results showed that microwaves inhibited the growth of JF305 cells in a dose-dependent manner, and caused morphological changes in apoptotic body formation. The percentages of apoptosis detected using annexin V-fluorescein isothiocyanate (FITC) were 4.0%, 10.0%, 12.0%, and 30.0% with the dosage of microwave (0, 5.0, 10.0, and 20.0 mW/cm(2)), respectively. Treatment with microwaves increased the activity of caspase-9 and caspase-3, down-regulated the expression of Bcl-2, and up-regulated the expression of Bax and CytoC. In addition, the expression level of p65 was increased whereas the level of IκBα down-regulated. Those results suggest that microwaves inhibit cell growth and induce apoptosis in JF305 cells through an NF-κB-regulated mitochondria-mediated pathway.


Asunto(s)
Apoptosis/efectos de la radiación , Microondas , Neoplasias Pancreáticas/radioterapia , Línea Celular Tumoral/efectos de la radiación , Proliferación Celular/efectos de la radiación , Glutatión Peroxidasa/metabolismo , Humanos , Malondialdehído/metabolismo , Mitocondrias/metabolismo , FN-kappa B/metabolismo , Neoplasias Pancreáticas/patología , Superóxido Dismutasa/metabolismo
11.
Mol Neurobiol ; 61(2): 646-661, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37656314

RESUMEN

This study aimed to investigate the molecular mechanisms underlying spinal cord ischemia-reperfusion (SCI/R) injury. Through RNA-Seq high-throughput sequencing and bioinformatics analysis, we found that EGFR was downregulated in the spinal cord of SCI/R mice and may function via mediating the JAK2/STAT3 signaling pathway. In vitro cell experiments indicated that overexpression of EGFR activated the JAK2/STAT3 signaling pathway and reduced neuronal apoptosis levels. In vivo animal experiments further confirmed this conclusion, suggesting that EGFR inhibits SCI/R-induced neuronal apoptosis by activating the JAK2/STAT3 signaling pathway, thereby improving SCI/R-induced spinal cord injury in mice. This study revealed the molecular mechanisms of SCI/R injury and provided new therapeutic strategies for treating neuronal apoptosis.


Asunto(s)
Daño por Reperfusión , Isquemia de la Médula Espinal , Animales , Ratones , Apoptosis , Receptores ErbB/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Janus Quinasa 2/metabolismo , Modelos Teóricos , Neuroprotección , Daño por Reperfusión/metabolismo , Médula Espinal/metabolismo , Factor de Transcripción STAT3/metabolismo
12.
Aging Dis ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38916730

RESUMEN

Tauopathies, a group of neurodegenerative disorders, are characterized by disrupted homeostasis of the microtubule binding protein tau. Nogo-A mainly hinders axonal growth and development in neurons, but the underlying mechanism of tau vulnerability has not been determined. Here, to gain more comprehensive insights into the impact of Nogo-A on tau protein expression, we showed that Nogo-A induces tau hyperphosphorylation, synapse loss and cognitive dysfunction. Consistent with the biological function of tau hyperphosphorylation, Nogo-A-induced tau hyperphosphorylation altered microtubule stability, which causes synaptic dysfunction. Mechanistically, Nogo-A-induced tau hyperphosphorylation was abolished by the Nogo-A antagonist NEP1-40 in primary neurons. Surprisingly, downregulation of Nogo-A in the hippocampus of AD mice (hTau. P301S) inhibited tau hyperphosphorylation at the AT8, Thr181, The231 and Ser404 sites and rescued synaptic loss and cognitive impairment in AD mice. Our findings exhibit a strong degree of consistency with Nogo-A-induced tauopathy vulnerability, reinforcing the coherence and reliability of our research. Furthermore, in mice, Nogo-A increases tauopathy vulnerability to exacerbate AD progression via ROCK/AKT/GSK3ß signaling. Together, our findings provide new insight into the function of Nogo-A in regulating tau hyperphosphorylation and reveal an effective treatment strategy for tauopathies.

13.
Ecol Evol ; 13(10): e10581, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37809361

RESUMEN

Cleistogenes songorica, as a clustered grass, is the main grassland flora of the Stipa breviflora desert grassland. Some studies have shown that the constructive species of S. breviflora (sparse cluster type) is prone to cluster fragmentation; however, research on C. songorica is relatively rare. Then will the C. songorica plant population (dense cluster type) also have cluster fragmentation under the influence of intense grazing? To answer this question, we used variance analysis and geo-statistical methods. The spatial distribution of C. songorica in S. breviflora desert steppe in Inner Mongolia was measured under four grazing intensities (no grazing, CK, 0 sheep·ha-1·half year-1; light grazing, LG, 0.93 sheep·ha-1·half year-1; moderate grazing, MG, 1.82 sheep·ha-1·half year-1; and heavy grazing, HG, 2.71 sheep·ha-1·half year-1) and four scales (10 cm × 10 cm, 20 cm × 20 cm, 25 cm × 25 cm, 50 cm × 50 cm). We then analyzed C. songorica whether fragmentation was present. The results showed that increased grazing intensity is associated with increased density and decreased height, coverage, and standing crop of C. songorica. The spatial distribution of C. songorica was affected by structural factors, and spatial heterogeneity decreased with increased spatial scale. With increased grazing intensity and spatial scale, the patch area of C. songorica gradually increased and tended toward band distribution. In summary, increased grazing intensity and spatial scale led to weakened heterogeneity of C. songorica spatial distribution and increased consistency.

14.
Front Plant Sci ; 14: 1230725, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37854116

RESUMEN

Seed banks are crucial regenerative resources for aboveground vegetation. The pattern of their changes holds immense significance in understanding alterations in the belowground seed bank. This understanding is pivotal for uncovering both short-term and long-term shifts in plant communities. Additionally, it contributes to the restoration of grassland ecosystems. To better protect grassland biodiversity and provide a theoretical basis for the restoration of degraded grasslands, in this study, the germination characteristics of soil seed banks in free-grazed, enclosed and mown areas were compared, and the results were combined with those of previous studies for a comprehensive analysis. The density of soil seed bank and perennial forage soil seed bank were significantly affected by different grassland utilization and soil depths. Grazing and enclosure grassland utilization methods increased the content of the soil seed bank, and mowing reduced the content of the seed bank. The soil seed bank density of perennial grasses accounted for the highest proportion under grazing, followed by mowing, and its lowest proportion was observed in the enclosures. Grazing not only facilitated the germination of the perennial grass seed bank but also substantially augmented its content. Mowing inhibited the germination of the upper growth grasses seed bank, which was particularly significant in the 0-2 cm soil layer under grazing. The content of the upper growth grasses seed bank affected the total seed bank to a certain extent, mainly in the 5-10 cm layer. The general correlations among the perennial grasses, upper growth grasses and soil germination seed bank resulted in 84.58% information extraction, and this information has practical significance for grassland ecological restoration.

15.
Can J Physiol Pharmacol ; 90(11): 1553-8, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23181283

RESUMEN

Induction of apoptosis in tumor cells has become the major focus of anti-tumor therapeutics development. Juglone, a major chemical constituent of Juglans mandshurica Maxim, possesses several bioactivities, including anti-tumor. In the present study, HeLa cells were incubated with juglone at various concentrations. The proliferation inhibition of juglone on HeLa cells was tested by the MTT assay. Occurrence of apoptosis was detected by Hoechst 33258 staining, flow cytometry, and transmission electron microscopy. The expression of apoptotic-related proteins was examined by Western blot. The results showed that juglone inhibits the growth of HeLa cells in dose-dependent manner. Topical morphological changes of apoptotic body formation after juglone treatment were observed. The percentages of early apoptosis of Annexin V-FITC were 5.23%, 7.95%, 10.69%, and 20.92% with the concentrations of juglone (12.5, 25, 50, and 100 µmol/L), respectively. After cells were treated with juglone at the different dose for 24 h, the expression of Bcl-2 was significantly down-regulated and the expression of Bax was significantly up-regulated compared with the control. These events paralleled with activation of caspase-9, -8, -3, and PARP cleavage. The results suggest that juglone may be effective for the treatment of HeLa cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Proteínas Reguladoras de la Apoptosis/metabolismo , Apoptosis/efectos de los fármacos , Carcinoma/tratamiento farmacológico , Naftoquinonas/farmacología , Proteínas de Neoplasias/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Proteínas Reguladoras de la Apoptosis/agonistas , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Western Blotting , Carcinoma/metabolismo , Carcinoma/ultraestructura , Caspasas/química , Caspasas/metabolismo , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Células HeLa , Humanos , Microscopía Electrónica de Transmisión , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/antagonistas & inhibidores , Concentración Osmolar , Poli(ADP-Ribosa) Polimerasa-1 , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteolisis/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/ultraestructura
16.
Front Genet ; 13: 1054035, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36468006

RESUMEN

Background and Objective: This study aims to find the key immune genes and mechanisms of low bone mineral density (LBMD) in ankylosing spondylitis (AS) patients. Methods: AS and LBMD datasets were downloaded from the GEO database, and differential expression gene analysis was performed to obtain DEGs. Immune-related genes (IRGs) were obtained from ImmPort. Overlapping DEGs and IRGs got I-DEGs. Pearson coefficients were used to calculate DEGs and IRGs correlations in the AS and LBMD datasets. Louvain community discovery was used to cluster the co-expression network to get gene modules. The module most related to the immune module was defined as the key module. Metascape was used for enrichment analysis of key modules. Further, I-DEGs with the same trend in AS and LBMD were considered key I-DEGs. Multiple machine learning methods were used to construct diagnostic models based on key I-DEGs. IID database was used to find the context of I-DEGs, especially in the skeletal system. Gene-biological process and gene-pathway networks were constructed based on key I-DEGs. In addition, immune infiltration was analyzed on the AS dataset using the CIBERSORT algorithm. Results: A total of 19 genes were identified I-DEGs, of which IFNAR1, PIK3CG, PTGER2, TNF, and CCL3 were considered the key I-DEGs. These key I-DEGs had a good relationship with the hub genes of key modules. Multiple machine learning showed that key I-DEGs, as a signature, had an excellent diagnostic performance in both AS and LBMD, and the SVM model had the highest AUC value. Key I-DEGs were closely linked through bridge genes, especially in the skeletal system. Pathway analysis showed that PIK3CG, IFNAR1, CCL3, and TNF participated in NETs formation through pathways such as the MAPK signaling pathway. Immune infiltration analysis showed neutrophils had the most significant differences between case and control groups and a good correlation with key I-DEG. Conclusion: The key I-DEGs, TNF, CCL3, PIK3CG, PTGER2, and IFNAR1, can be utilized as biomarkers to determine the risk of LBMD in AS patients. They may affect neutrophil infiltration and NETs formation to influence the bone remodeling process in AS.

17.
Biomed Pharmacother ; 153: 113321, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35759868

RESUMEN

Muscarinic acetylcholine receptors (mAChRs) are widely expressed in various effector cells and have been proved to play vital roles in smooth muscle contraction and digestive secretion. However, there are relatively few literatures revealing the roles of mAChRs in inflammatory processes, and its underlying regulatory mechanisms have not been elucidated. Taking the advantages of live imaging of zebrafish, we found that inhibition of mAChRs resulted in increased neutrophils recruitment and proinflammatory cytokines expression, whereas activation of mAChRs led to opposite outcome. Subsequently, we found that mAChRs regulated the expression of arginases (args), and pharmacological intervention of args level could reverse the effects of mAChRs on neutrophils migration and cytokines expression, suggesting that args are important downstream proteins of mAChRs that mediate the regulation of inflammatory response. In this study, we identified args as novel downstream proteins of mAChRs in inflammatory responses, providing additional evidence for system immune regulation of cholinergic receptors.


Asunto(s)
Arginasa , Pez Cebra , Animales , Citocinas , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Pez Cebra/metabolismo
18.
Biomed Pharmacother ; 153: 113268, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35777221

RESUMEN

Fluoxetine (FLX), a selective serotonin reuptake inhibitor (SSRI), increases the serotonin levels in the brain to treat depression. Antidepressants have been demonstrated to modulate circadian rhythm, but the underlying mechanisms by which antidepressants regulate circadian rhythm require more research. This study aimed to investigate the role of FLX on circadian rhythm by analyzing the movement behavior and internal circadian oscillations in zebrafish. The results showed that the expression of clock genes clock1a and bmal1b was significantly down-regulated, and the amplitude reduction and phase shift were observed after FLX treatment. Furthermore, FLX exposure inhibited the expression of aanat2, which led to a decrease in nocturnal melatonin secretion. aanat2-/- larvae showed disrupted circadian rhythm. These findings may help reveal the effect of FLX exposure on the circadian rhythm and locomotor activity. It may provide theoretical data for the clinical application of FLX.


Asunto(s)
Fluoxetina , Melatonina , Animales , Antidepresivos/farmacología , Ritmo Circadiano/genética , Fluoxetina/farmacología , Melatonina/metabolismo , Melatonina/farmacología , Pez Cebra/metabolismo
19.
Medicine (Baltimore) ; 99(16): e19782, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32311987

RESUMEN

RATIONALE: Congenital proximal radioulnar synostosis is a rare genetic malformation of the upper limb. This deformity, which is found mainly in preschool-aged children, has no recognized diagnosis and treatment. Current diagnostic methods cannot effectively assess both bone structure and soft tissue abnormalities, and most surgical treatments introduce complications and do not prevent recurrence. More work is needed; therefore, to address the diagnosis and treatment of this disease. PATIENT CONCERNS: An 8-year-old male patient was hospitalized in our department. He reported deformity and limited motion in his right elbow for the past 2 years. He denied a traumatic or family history of bony malformation. The chief complaint at the time of the hospitalization was the limitation in forearm rotation. DIAGNOSIS: Digital radiography of the right elbow joint showed proximal radioulnar synostosis and a valgus deformity. A 3-dimensional computed tomography scan further showed proximal ulna and radius dysplasia as well as anterior dislocation of the radius head. The patient was diagnosed with congenital right proximal radioulnar synostosis. INTERVENTIONS: Surgical procedures included arthrolysis of the right proximal radioulnar joint, osteotomy of the proximal radius, internal fixation with Kirschner wires, and reconstruction of the annular ligament. The right elbow was immobilized in plaster in a flexion and supination position for 2 weeks. OUTCOMES: Recurrence of the right proximal radioulnar synostosis was observed during the 6-month follow-up, but the rotation function of the patient's forearm was significantly improved. LESSONS: The findings from this case suggest that we should carefully monitor all patients younger than 6 years old who report long-term issues with forearm rotation. This case also highlights the need to assess soft tissue and epiphysis abnormalities in addition to bone assessments via digital radiography and 3-dimensional computed tomography. We suggest that surgery should not be performed until the proximal radius epiphysis has closed. Not all cases require surgical treatment, but when surgery is needed, a suitable method should be selected according to the individual needs of the patient. Any surgery performed should treat both the bony malformations and soft tissue abnormalities to maximize the therapeutic effect and reduce complications during and after surgery.


Asunto(s)
Procedimientos Ortopédicos/métodos , Radio (Anatomía)/anomalías , Sinostosis/cirugía , Cúbito/anomalías , Niño , Humanos , Masculino , Radio (Anatomía)/diagnóstico por imagen , Radio (Anatomía)/cirugía , Sinostosis/diagnóstico por imagen , Cúbito/diagnóstico por imagen , Cúbito/cirugía
20.
J Biomed Mater Res A ; 108(11): 2230-2239, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32363671

RESUMEN

The gelatin film has great potential in biomedical applications, especially in wound healing. The combination of gelatin films and stem cells could further accelerate the skin regeneration. Although polysaccharide modification can improve the mechanical property and biological activity of gelatin films, information about the stability and cellular affinity is still limited. This study investigated the influence of polysaccharides on the stability and cellular affinity of gelatin films. Two kinds of gelatin-polysaccharide composite films, including gelatin-hyaluronic acid (G-HA) and gelatin-chitosan (G-CS), were prepared in this study. It was found that G-HA composite film had better short-term and long-term stability compared with G-CS composite film. And G-HA composite film also had better biological safety than G-CS film. Moreover, the surface of G-HA composite film supported the adhesion and growth of human umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ MSCs) better than G-CS film surface. These data illustrated that G-HA composite film has better stability and cellular affinity compared with G-CS film, which could be considered a promising delivery system of stem cells for further in vivo studies. Therefore, this work would be very helpful to optimize the preparation of gelatin-polysaccharide composite films.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Gelatina/química , Ácido Hialurónico/química , Células Madre Mesenquimatosas/citología , Adhesión Celular , Línea Celular , Proliferación Celular , Células Cultivadas , Humanos , Cordón Umbilical/citología , Gelatina de Wharton/citología
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