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1.
Cell Death Dis ; 15(6): 416, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879600

RESUMO

Tripartite motif 8 (TRIM8) is an E3 ligase that plays dual roles in various tumor types. The biological effects and underlying mechanism of TRIM8 in hepatocellular carcinoma (HCC) remain unknown. Hepatocyte nuclear factor 1α (HNF1α) is a key transcriptional factor that plays a significant role in regulating hepatocyte differentiation and liver function. The reduced expression of HNF1α is a critical event in the development of HCC, but the underlying mechanism for its degradation remains elusive. In this study, we discovered that the expression of TRIM8 was upregulated in HCC tissues, and was positively correlated with aggressive tumor behavior of HCC and shorter survival of HCC patients. Overexpression of TRIM8 promoted the proliferation, colony formation, invasion, and migration of HCC cells, while TRIM8 knockdown or knockout exerted the opposite effects. RNA sequencing revealed that TRIM8 knockout suppresses several cancer-related pathways, including Wnt/ß-catenin and TGF-ß signaling in HepG2 cells. TRIM8 directly interacts with HNF1α, promoting its degradation by catalyzing polyubiquitination on lysine 197 in HCC cells. Moreover, the cancer-promoting effects of TRIM8 in HCC were abolished by the HNF1α-K197R mutant in vitro and in vivo. These data demonstrated that TRIM8 plays an oncogenic role in HCC progression through mediating the ubiquitination of HNF1α and promoting its protein degradation, and suggests targeting TRIM8-HNF1α may provide a promising therapeutic strategy of HCC.


Assuntos
Carcinoma Hepatocelular , Progressão da Doença , Fator 1-alfa Nuclear de Hepatócito , Neoplasias Hepáticas , Ubiquitinação , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Fator 1-alfa Nuclear de Hepatócito/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética
2.
J Ginseng Res ; 47(6): 694-705, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38107396

RESUMO

Panax ginseng Meyer is a traditional Chinese medicine that is widely used as tonic in Asia. The main pharmacologically active components of ginseng are the dammarane-type ginsenosides, which have been shown to have anti-cancer, anti-inflammatory, immunoregulatory, neuroprotective, and metabolic regulatory activities. Moreover, some of ginsenosides (eg, Rh2 and Rg3) have been developed into nutraceuticals. However, the utilization of ginsenosides in clinic is restrictive due to poor permeability in cells and low bioavailability in human body. Obviously, the dammarane skeleton and glycosyls of ginsenosides are responsible for these limitations. Therefore, improving the oral bioavailability of ginsenosides has become a pressing issue. Here, based on the structures of ginsenosides, we summarized the understanding of the factors affecting the oral bioavailability of ginsenosides, introduced the methods to enhance the oral bioavailability and proposed the future perspectives on improving the oral bioavailability of ginsenosides.

3.
Phytomedicine ; 121: 155131, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806155

RESUMO

BACKGROUND: Liver cancer is a topical global health issue. The treatment of liver cancer meets significant challenges in the high recurrence rate and invasive incidence. Therefore, the treatment strategies that target epithelial-mesenchymal transition (EMT) induced by cyclooxygenase 2 (COX2)/ prostaglandin E2 (PGE2) pathway have become epidemic. Ginsenoside Rh2 has been proved to inhibit the EMT. However, the underlying mechanisms remain unclear. Moreover, the octyl ester derivative of Rh2 (Rh2-O) exhibited superior anti-proliferative and immunomodulatory effects than Rh2 in our previous researches, which indicated that Rh2-O might also exert inhibitory effects on invasion and metastasis. PURPOSE: The aim of current study is to explore the inhibitory effects of Rh2 and Rh2-O on invasion and metastasis of hepatocellular carcinoma, and to investigate whether these effects are dependent on the c-Jun/COX2/PGE2 pathway. STUDY DESIGN: The Huh-7 liver cancer cells and the H22 tumor-bearing mice were treated with Rh2 and Rh2-O. METHOD: In this paper, the inhibitory effects of Rh2 and Rh2-O on invasion and metastasis were tested by wound healing, trans-well assay and tumor-bearing mice, and the involvement of c-Jun/COX2/PGE2 pathway were verified by exogenous PGE2, activation of COX2 and overexpression of c-Jun. RESULTS: The results showed that Rh2 and Rh2-O could efficiently inhibit the invasion and metastasis in a dose-dependent manner (p < 0.05). And the Rh2-O showed stronger effects than Rh2. Moreover, the exogenous PGE2, activation of COX2 by exogenous LPS and the overexpression of c-Jun by transfection all reversed the inhibitory effects of Rh2 and Rh2-O on metastasis or EMT (p < 0.05). CONCLUSION: Rh2 and Rh2-O could inhibit the invasion and metastasis of hepatocellular carcinoma via restraining the EMT, which was mediated by c-Jun/COX2/PGE2 pathway.


Assuntos
Carcinoma Hepatocelular , Ginsenosídeos , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Dinoprostona/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Ciclo-Oxigenase 2/metabolismo , Ésteres/uso terapêutico , Ginsenosídeos/metabolismo , Linhagem Celular Tumoral
4.
Mutat Res ; 827: 111830, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37437506

RESUMO

OBJECTIVE: The purpose of this study is to identify potential targets associated with breast cancer and screen potential small molecule drugs using bioinformatics analysis. METHODS: DEGs analysis of breast cancer tissues and normal breast tissues was performed using R language limma analysis on the GSE42568 and GSE205185 datasets. Functional enrichment analysis was conducted on the intersecting DEGs. The STRING analysis platform was used to construct a PPI network, and the top 10 core nodes were identified using Cytoscape software. QuartataWeb was utilized to build a target-drug interaction network and identify potential drugs. Cell survival and proliferation were assessed using CCK8 and colony formation assays. Cell cycle analysis was performed using flow cytometry. Western blot analysis was conducted to assess protein levels of PLK1, MELK, AURKA, and NEK2. RESULTS: A total of 54 genes were consistently upregulated in both datasets, which were functionally enriched in mitotic cell cycle and cell cycle-related pathways. The 226 downregulated genes were functionally enriched in pathways related to hormone level regulation and negative regulation of cell population proliferation. Ten key genes, namely CDK1, CCNB2, ASPM, AURKA, TPX2, TOP2A, BUB1B, MELK, RRM2, and NEK2 were identified. The potential drug Fostamatinib was predicted to target AURKA, MELK, CDK1, and NEK2. In vitro experiments demonstrated that Fostamatinib inhibited the proliferation of breast cancer cells, induced cell arrest in the G2/M phase, and down-regulated MELK, AURKA, and NEK2 proteins. CONCLUSION: In conclusion, Fostamatinib shows promise as a potential drug for the treatment of breast cancer by regulating the cell cycle and inhibiting the proliferation of breast cancer cells.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Aurora Quinase A/genética , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Proteínas Serina-Treonina Quinases/genética , Quinases Relacionadas a NIMA/genética
5.
Sci Total Environ ; 858(Pt 2): 159858, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36374756

RESUMO

Leaf senescence is the final stage in the life cycle of leaves and is critical to plants' fitness as well as to ecosystem carbon and nutrient cycling. To date, most understanding about the responses of leaf senescence to environmental changes has derived from research in forests, but the topic has been relatively neglected, especially under grazing conditions, in natural grasslands. We conducted a 3-year manipulative asymmetric warming with moderate grazing experiment to explore the responses of leaf senescence of five main species in an alpine meadow on the Qinghai-Tibetan Plateau. We found that warming prolonged leaf longevity through earlier leaf-out and later leaf senescence, and grazing prolonged it through a greater advance in leaf-out than first leaf coloration for all plants. Warming did not affect leaf nitrogen (N) content or N resorption efficiency (NRE), but grazing increased N content in coloring leaves for P. anserine and P. nivea and decreased NRE for K. humilis, P. anserine under no-warming, and for P. nivea under warming. The interactive effects of warming and grazing on leaf phenology and leaf traits depended on species identity and year. There were positive relationships between leaf-out and leaf senescence mainly derived from grazing, and positive relationships between NRE from old leaves and leaf senescence for three out of five plant species. Therefore, our results indicated that earlier leaf-out could result in earlier leaf senescence only under grazing, but depending on plant species. Delayed leaf coloring increased NRE from old leaves for some plant species measured under warming and grazing. Our results suggested that alpine plants may develop strategies to adapt to warming and grazing to assimilate more carbon through prolonged leaf longevity rather than increased NRE through earlier leaf coloring in the alpine meadow.


Assuntos
Ecossistema , Pradaria , Anserina , Senescência Vegetal , Plantas , Carbono
6.
Sci Adv ; 8(22): eabm9603, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35658029

RESUMO

Flavanols are privileged heterocyclic compounds in medicinal chemistry. It is notable to develop an efficient and straightforward protocol for accessing chiral flavanols with precise control of the stereocenters. Here, a highly efficient kinetic resolution of chromenes was reported via Cu-catalyzed asymmetric hydroboration. This previously unidentified approach features a one-step synthesis of chiral flavan-3-ols containing two vicinal stereogenic centers via a highly efficient kinetic resolution (s factor up to 1060, >99% ee for most products). In addition, the anti-inflammation effects of these diversified flavan-3-ols were studied by the in vitro experiments and RNA sequencing analysis. These flavan-3-ols showed inhibitory effects on the secretion of pro-inflammation cytokines including interleukin-1ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α), as well as inhibiting the inflammation responses through down-regulating the gene transcriptions closely related to PI3K-Akt signaling pathway and TNF signaling pathway. The results suggested that these newly synthesized flavan-3-ols have the potential to be lead compounds for anti-inflammatory drugs.


Assuntos
Benzopiranos , Cobre/química , Fosfatidilinositol 3-Quinases , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Benzopiranos/farmacologia , Catálise , Humanos , Inflamação/tratamento farmacológico
7.
Chem Commun (Camb) ; 58(15): 2468-2471, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35024704

RESUMO

We report a new osmium(VI) nitrido complex bearing a nonplanar tetradentate ligand with potent anticancer activity. This complex causes mitochondrial damage, which induces liver cancer cell death via oncosis and apoptosis. This is the first osmium-based anticancer candidate that induces oncosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Mitocôndrias/efeitos dos fármacos , Nitrilas/farmacologia , Osmio/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Mitocôndrias/metabolismo , Estrutura Molecular , Nitrilas/química , Osmio/química
8.
J Vis Exp ; (177)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34927612

RESUMO

The primary cilium is a critical signaling organelle found on nearly every cell that transduces Hedgehog (Hh) signaling stimuli from the cell surface. In the granule cell precursor (GCP), the primary cilium acts as a pivotal signaling center that orchestrates precursor cell proliferation by modulating the Hh signaling pathway. The investigation of primary cilium-dependent Hh signaling machinery is facilitated by in vitro genetic manipulation of the pathway components to visualize their dynamic localization to the primary cilium. However, transfection of transgenes in the primary cultures of GCPs using the currently known electroporation methods is generally costly and often results in low cell viability and undesirable transfection efficiency. This paper introduces an efficient, cost-effective, and simple electroporation protocol that demonstrates a high transfection efficiency of ~80-90% and optimal cell viability. This is a simple, reproducible, and efficient genetic modification method that is applicable to the study of the primary cilium-dependent Hedgehog signaling pathway in primary GCP cultures.


Assuntos
Cílios , Proteínas Hedgehog , Cílios/metabolismo , Análise Custo-Benefício , Eletroporação , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Transdução de Sinais/genética
9.
Glob Chang Biol ; 27(20): 5198-5210, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34228871

RESUMO

Changes in ecological processes over time in ambient treatments are often larger than the responses to manipulative treatments in climate change experiments. However, the impacts of human-driven environmental changes on the stability of natural grasslands have been typically assessed by comparing differences between manipulative plots and reference plots. Little is known about whether or how ambient climate regulates the effects of manipulative treatments and their underlying mechanisms. We collected two datasets, one a 36-year long-term observational dataset from 1983 to 2018, and the other a 10-year manipulative asymmetric warming and grazing experiment using infrared heaters with moderate grazing from 2006 to 2015 in an alpine meadow on the Tibetan Plateau. The 36-year observational dataset shows that there was a nonlinear response of community stability to ambient temperature with a positive relationship between them due to an increase in ambient temperature in the first 25 years and then a decrease in ambient temperature thereafter. Warming and grazing decreased community stability with experiment duration through an increase in legume cover and a decrease in species asynchrony, which was due to the decreasing background temperature through time during the 10-year experiment period. Moreover, the temperature sensitivity of community stability was higher under the ambient treatment than under the manipulative treatments. Therefore, our results suggested that ambient climate may control the directional trend of community stability while manipulative treatments may determine the temperature sensitivity of the response of community stability to climate relative to the ambient treatment. Our study emphasizes the importance of the context dependency of the response of community stability to human-driven environmental changes.


Assuntos
Mudança Climática , Pradaria , Herbivoria , Temperatura
10.
Polymers (Basel) ; 13(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374746

RESUMO

In this paper, surface projection micron stereo-lithography technology (PµSL) by 3D printing was used to prepare two resin honeycomb materials with different levels, and the mechanical behavior of these materials was studied. The quasi-static compression experiment and the dynamic compression experiment were carried out on the samples using the in situ micro-compression testing machine and the Split Hopkinson bar (SHPB) experimental equipment. The stress-strain curves of these materials at different strain rates were obtained, and the energy absorption characteristic of materials with two different levels were analyzed. This article reveals that the collapse strength and energy absorption properties of the materials are related to the hierarchical level of honeycomb. Multi-level hierarchical honeycomb (MHH) has higher collapse strength and better energy absorption properties than single-level hierarchical honeycomb (SHH). It turned out that increasing the hierarchical level of honeycomb could improve the mechanical properties of the materials. In the future development of products, the mechanical properties of hierarchical material by 3D printing can be further optimized through changing the level of the fractal structure.

11.
Sci Total Environ ; 745: 140999, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32738686

RESUMO

Phenology has a great effect on the carbon cycle. Significant relationships have been well demonstrated between phenology and photosynthesis. However, few studies have been undertaken to characterize relationships between phenology and ecosystem respiration (Re). We conducted a reciprocal transplant experiment among three elevations for two-years to measure Re over six phenological sequences throughout the growing seasons. Our results showed that changes in phenological duration were mainly determined by the onset of phenology, as one day advance of phenological onset could lengthen 0.13 days of phenological duration. Advances in early spring phenophases (i.e., first leaf-out, first bud/boot-set and first flowering) under warming strengthened the temperature sensitivity of Re. However, the late phenophases (i.e., first seeding-set, first post-fruiting vegetation and first leaf-coloring) had non-significant relationships with Re. In total, after pooling all the data, one day advance of phenophases would increase Re by 2.23% under warming. In particular, Re would increase by 29.12% with an advance of phenophases by 8.46 days of under a 1.5 °C warming scenario. Our analysis of the coupling between temperature/moisture-phenology-Re may further supplement evidence that warmer spring temperature increases carbon emission by advancing early phenophases. This points to a faster and easier way to investigate how aboveground functional traits (phenology) affect unseen functional traits (Re) on the Tibetan Plateau.


Assuntos
Mudança Climática , Ecossistema , Carbono , Estações do Ano , Temperatura
12.
Int J Clin Pharmacol Ther ; 58(10): 531-538, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32716292

RESUMO

OBJECTIVE: The aim of this study was to analyze the pharmacokinetics/pharmacodynamics (PK/PD) of higher-dose tigecycline (100 mg q12h) in severely infected intensive care unit (ICU) patients receiving continuous renal replacement therapy (CRRT). MATERIALS AND METHODS: In this prospective single-center observational study, severely infected patients receiving intravenous tigecycline were enrolled. They were divided into a CRRT group (7 cases) and a non-CRRT group (9 cases). The blood samples and CRRT ultrafiltrate were collected. The drug concentration in each sample was determined by a HPLC-UV method. The pharmacokinetic parameters were simulated and calculated with DAS 2.0. The PK/PD parameters were evaluated according to published data. The registration number of this study is NCT02931526 in ClinicalTrials.gov. RESULTS: In the non-CRRT group, Cmax, Cmin, and AUC0-24 were 1.00 ± 0.66 µg×mL-1, 0.20 ± 0.12 µg×mL-1, and 22.12 ± 14.46 µg×h×mL-1, respectively. The clinical efficiency was 55.6%, and the bacterial clearance rate was 77.8%. In the CRRT group, Cmax, Cmin, and AUC0-24 were 0.96 ± 0.31 µg×mL-1, 0.22 ± 0.12 µg×mL-1, and 19.90 ± 8.14 µg×h×mL-1, respectively. The clinical efficiency was 28.6%, and the bacterial clearance rate was 28.6%. The individual differences of tigecycline plasma concentrations in our study were widely variable, and the differences of the two groups' PK/PD parameters had no statistical significance (p < 0.05). CONCLUSION: CRRT may have had little influence in tigecycline metabolism in our study, and therapeutic drug monitoring needs to be introduced for critically ill patients because of various pharmacokinetic parameters.


Assuntos
Terapia de Substituição Renal Contínua , Antibacterianos , Estado Terminal , Humanos , Estudos Prospectivos , Tigeciclina
13.
Glob Chang Biol ; 26(4): 2630-2641, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31883193

RESUMO

Warming in cold regions alters freezing and thawing (F-T) of soil in winter, exposing soil organic carbon to decomposition. Carbon-rich permafrost is expected to release more CO2 to the atmosphere through ecosystem respiration (Re) under future climate scenarios. However, the mechanisms of the responses of freeze-thaw periods to climate change and their coupling with Re in situ are poorly understood. Here, using 2 years of continuous data, we test how changes in F-T events relate to annual Re under four warming levels and precipitation addition in a semi-arid grassland with discontinuous alpine permafrost. Warming shortened the entire F-T period because the frozen period shortened more than the extended freezing period. It decreased total Re during the F-T period mainly due to decrease in mean Re rate. However, warming did not alter annual Re because of reduced soil water content and the small contribution of total Re during the F-T period to annual Re. Although there were no effects of precipitation addition alone or interactions with warming on F-T events, precipitation addition increased total Re during the F-T period and the whole year. This decoupling between changes in soil freeze-thaw events and annual Re could result from their different driving factors. Our results suggest that annual Re could be mainly determined by soil water content rather than by change in freeze-thaw periods induced by warming in semi-arid alpine permafrost.

14.
Glob Chang Biol ; 25(10): 3438-3449, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31373124

RESUMO

Changes in labile carbon (LC) pools and microbial communities are the primary factors controlling soil heterotrophic respiration (Rh ) in warming experiments. Warming is expected to initially increase Rh but studies show this increase may not be continuous or sustained. Specifically, LC and soil microbiome have been shown to contribute to the effect of extended warming on Rh . However, their relative contribution is unclear and this gap in knowledge causes considerable uncertainty in the prediction of carbon cycle feedbacks to climate change. In this study, we used a two-step incubation approach to reveal the relative contribution of LC limitation and soil microbial community responses in attenuating the effect that extended warming has on Rh . Soil samples from three Tibetan ecosystems-an alpine meadow (AM), alpine steppe (AS), and desert steppe (DS)-were exposed to a temperature gradient of 5-25°C. After an initial incubation period, soils were processed in one of two methods: (a) soils were sterilized then inoculated with parent soil microbes to assess the LC limitation effects, while controlling for microbial community responses; or (b) soil microbes from the incubations were used to inoculate sterilized parent soils to assess the microbial community effects, while controlling for LC limitation. We found both LC limitation and microbial community responses led to significant declines in Rh by 37% and 30%, respectively, but their relative contributions were ecosystem specific. LC limitation alone caused a greater Rh decrease for DS soils than AMs or ASs. Our study demonstrates that soil carbon loss due to Rh in Tibetan alpine soils-especially in copiotrophic soils-will be weakened by microbial community responses under short-term warming.


Assuntos
Microbiota , Solo , Carbono , Microbiologia do Solo , Tibet
15.
Sci Rep ; 9(1): 8063, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31147592

RESUMO

The overland flow erosion is common and became more serious because of the climate warming inducing more runoff in the Tibet Plateau. The purposes of this study were to evaluate the effects of flow rate, slope gradient, shear stress, stream power, unit stream power and unit energy of water-carrying section on the soil detachment capacity for the soil in the Tibet Plateau of China due to the information is limited. To achieve this aim, laboratory experiments were performed under six flow rates (5, 10, 15, 20, 25 and 30 L min-1) and six slope gradients (8.74%, 17.63%, 26.79%, 36.40%, 46.63 and 57.73%) by using a slope-adjustable steel hydraulic flume (4 m length, 0.4 m width, 0.2 m depth). The results indicated that soil detachment capacity ranged from 0.173 to 6.325 kg m-2 s-1 with 1.972 kg m-2 s-1 on average. The soil detachment capacity increased with power function as the flow rate and the slope gradient augmented (R2 = 0.965, NRMSE = 0.177 and NSE = 0.954). The soil detachment capacity was more influenced by flow rate than by slope gradient in this study. The relation between soil detachment capacity and shear stress, stream power, unit stream power and unit energy of water-carrying section can be described by using the linear function and power function, the power function relationship performed better than the linear function in generally. The stream power exhibits the best performance in describing the soil detachment capacity among shear stress, stream power, unit stream power and unit energy of water-carrying section in this study. The erodibility value in this study was larger than and the critical shear stress was less than those for soil in the eastern China. There has a huge potential for the soil in the Tibet Plateau eroded by the water erosion when enough runoff exiting. More attention should be payed to the water erosion process and mechanism in the Tibet Plateau area in the future.

16.
Ecology ; 100(9): e02775, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31169904

RESUMO

Changes in day (maximum temperature, TMAX ) and night temperature (minimum temperature, TMIN ) in the preseason (e.g., winter and spring) may have opposite effects on early phenophases (e.g., leafing and flowering) due to changing requirements of chilling accumulations (CAC) and heating accumulations (HAC), which could cause advance, delay or no change in early phenophases. However, their relative effects on phenology are largely unexplored, especially on the Tibetan Plateau. Here, observations were performed using a warming and cooling experiment in situ through reciprocal transplantation (2008-2010) on the Tibetan Plateau. We found that winter minimum temperature (TMIN ) warming significantly delayed mean early phenophases by 8.60 d/°C, but winter maximum temperature (TMAX ) warming advanced them by 12.06 d/°C across six common species. Thus, winter mean temperature warming resulted in a net advance of 3.46 d/°C in early phenophases. In contrast, winter TMIN cooling, on average, significantly advanced early phenophases by 5.12 d/°C, but winter TMAX cooling delayed them by 7.40 d/°C across six common species, resulting in a net delay of 2.28 d/°C for winter mean temperature cooling. The opposing effects of TMAX and TMIN warming on the early phenophases may be mainly caused by decreased CAC due to TMIN warming (5.29 times greater than TMAX ) and increased HAC due to TMAX warming (3.25 times greater than TMIN ), and similar processes apply to TMAX and TMIN cooling. Therefore, our study provides another insight into why some plant phenophases remain unchanged or delayed under climate change.


Assuntos
Mudança Climática , Plantas , Temperatura Baixa , Estações do Ano , Temperatura
17.
Rev Neurosci ; 30(3): 261-277, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30204590

RESUMO

Autophagy is an essential and conserved cellular homeostatic process. Defects in the core and accessory components of the autophagic machinery would most severely impact terminally differentiated cells, such as neurons. The neurodevelopmental/neurodegenerative disorder ß-propeller protein-associated neurodegeneration (BPAN) resulted from heterozygous or hemizygous germline mutations/pathogenic variant of the X chromosome gene WDR45, encoding WD40 repeat protein interacting with phosphoinositides 4 (WIPI4). This most recently identified subtype of the spectrum of neurodegeneration with brain iron accumulation diseases is characterized by a biphasic mode of disease manifestation and progression. The first phase involves early-onset of epileptic seizures, global developmental delay, intellectual disability and autistic syndrome. Subsequently, Parkinsonism and dystonia, as well as dementia, emerge in a subacute manner in adolescence or early adulthood. BPAN disease phenotypes are thus complex and linked to a wide range of other neuropathological disorders. WIPI4/WDR45 has an essential role in autophagy, acting as a phosphatidylinositol 3-phosphate binding effector that participates in autophagosome biogenesis and size control. Here, we discuss recent updates on WIPI4's mechanistic role in autophagy and link the neuropathological manifestations of BPAN's biphasic infantile onset (epilepsy, autism) and adolescent onset (dystonic, Parkinsonism, dementia) phenotypes to neurological consequences of autophagy impairment that are now known or emerging in many other neurodevelopmental and neurodegenerative disorders. As monogenic WDR45 mutations in BPAN result in a large spectrum of disease phenotypes that stem from autophagic dysfunctions, it could potentially serve as a simple and unique genetic model to investigate disease pathology and therapeutics for a wider range of neuropathological conditions with autophagy defects.


Assuntos
Autofagia/fisiologia , Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Distúrbios do Metabolismo do Ferro/metabolismo , Animais , Humanos , Doenças Neurodegenerativas/metabolismo , Neuropatologia/métodos
18.
PLoS One ; 12(8): e0181952, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28763467

RESUMO

This study aimed to investigate the effects of anti-tumor necrosis factor (TNF)-α antibody (Ab) on alteration of penile structure in the hyperprolactinemia (hyperPRL) rat model. HyperPRL was induced in 8-week-old male Sprague-Dawley rats by allografting anterior pituitary (AP) glands under the renal capsule (+AP rats). Rats implanted with cerebral cortex (CX) were used as sham control (+CX rats). At 6 weeks post implantation, rats received either a single intra-testicular dose of TNF-α Ab (12.5 µg/kg) or testosterone replacement (2 doses of testosterone enanthate [TE], 3 mg/kg), and they were sacrificed 1 week later. Blood and penile tissue was collected for analysis. Compared to +CX rats, the +AP group had lower serum testosterone concentration and neuronal nitric oxide synthase (nNOS) expression, but exhibited a higher ratio of collagen III/I in the corpus cavernosum. Smooth muscle content exhibited no significant changes. At 1 week post TNF-α Ab injection, the collagen III/I ratio in the +AP group was decreased, and the smooth muscle content and nNOS expression increased significantly. These findings were comparable to those observed in +AP rats receiving TE. Testicular TNF-α suppresses testosterone release, which in turn results in the erectile dysfunction (ED) seen in hyperPRL. Intra-testicular TNF-α Ab treatment is as effective as testosterone supplementation on penile structure normalization in the hyperPRL model.


Assuntos
Anticorpos/farmacologia , Hiperprolactinemia/sangue , Pênis/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Córtex Cerebral/metabolismo , Colágeno/química , Disfunção Erétil/fisiopatologia , Macrófagos/metabolismo , Masculino , Músculo Liso/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Ereção Peniana , Prolactina/sangue , Prolactina/metabolismo , Ratos , Ratos Sprague-Dawley , Testosterona/sangue , Testosterona/metabolismo
19.
Chin Med J (Engl) ; 129(10): 1200-7, 2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27174329

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) are bone marrow stem cells which play an important role in tissue repair. The treatment with MSCs will be likely to aggravate the degree of fibrosis. The Wnt/ß-catenin signaling pathway is involved in developmental and physiological processes, such as fibrosis. Dickkopfs (DKKs) are considered as an antagonist to block Wnt/ß-catenin signaling pathway by binding the receptor of receptor-related protein (LRP5/6). DKK1 was chosen in attempt to inhibit fibrosis of MSCs by lowering activity of Wnt/ß-catenin signaling pathway. METHODS: Stable MSCs were randomly divided into four groups: MSCs control, MSCs + transforming growth factor-ß (TGF-ß), MSCs + DKK1, and MSCs + TGF-ß + DKK1. Flow cytometry was used to identify MSCs. Cell viability was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide test. Immunofluorescence was used to detect protein expression in the Wnt/ß-catenin signaling pathways. Western blotting analysis was employed to test expression of fibroblast surface markers and, finally, real-time reverse transcription polymerase chain reaction was employed to test mRNA expression of fibroblast surface markers and Wnt/ß-catenin signaling proteins. RESULTS: Cultivated MSCs were found to conform to the characteristics of standard MSCs: expression of cluster of differentiation (CD) 73, 90, and 105, not expression of 34, 45, and 79. We found that DKK1 could maintain the normal cell morphology of MSCs. Western blotting analysis showed that fibroblast surface markers were expressed in high quantities in the group MSCs + TGF-ß. However, the expression was lower in the MSCs + TGF-ß + DKK1. Immunofluorescence showed high expression of all Wnt/ß-catnin molecules in the MSCs + TGF-ß group but expressed in lower quantities in MSCs + TGF-ß + DKK1 group. Finally, mRNA expression of fibroblast markers vimentin, α-smooth muscle actin and Wnt/ß-catenin signaling proteins ß-catenin, T-cell factor, and glycogen synthase kinase-3ß was significantly increased in MSCs + TGF-ß group compared to control (P < 0.05). Expression of the same fibroblast markers and Wnt/ß-catenin was decreased to regular quantities in the MSCs + TGF-ß + DKK1 group. CONCLUSIONS: DKK1, Wnt/ß-catenin inhibitors, blocks the Wnt/ß-catenin signaling pathway to inhibit the process of MSCs fibrosis. It might provide some new ways for clinical treatment of certain diseases.


Assuntos
Fibroblastos/citologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco Mesenquimais/citologia , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Células-Tronco Mesenquimais/metabolismo , Camundongos , Ratos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 34(6): 600-605, 2016 Dec 01.
Artigo em Chinês | MEDLINE | ID: mdl-28318161

RESUMO

OBJECTIVE: This study aimed to explore the period of endodontic treatment and the effects of periodontal-endodontic treatment for advanced periodontitis. METHODS: A total of 180 patients with advanced periodontitis participated in this clinical multicenter study. The respondents were randomly divided into an endodontic combined treatment (experimental) group and a periodontal treatment alone (control) group; each group consisted of 90 teeth. The control group received periodontal therapy only. The experimental group received periodontal therapy and root-canal treatment, and then pulp status was recorded. The cases were followed up at 1, 3, 6, and 12 months after treatment. RESULTS: Out of 90 teeth in the test group, 22 teeth had completely necrotic pulps, 45 teeth had partial necrosis (coronal pulp necrosis or root pulp necrosis), and 23 had vital pulp. Differences between clinical parameters in the control and experimental groups were not significant (P>0.05) before treatment but were significant after three months (P<0.05). CONCLUSIONS: Pulp treatment for teeth with advanced periodontitis and dull pulp vitality can control the development of inflammation and thus benefit the healing of periodontal tissue.


Assuntos
Periodontite , Polpa Dentária , Necrose da Polpa Dentária , Humanos , Raiz Dentária
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