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1.
Bone ; 182: 117050, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38367924

RESUMO

Postmenopausal osteoporosis (PMOP) is a common kind of osteoporosis that is associated with excessive osteocyte death and bone loss. Previous studies have shown that TNF-α-induced osteocyte necroptosis might exert a stronger effect on PMOP than apoptosis, and TLR4 can also induce cell necroptosis, as confirmed by recent studies. However, little is known about the relationship between TNF-α-induced osteocyte necroptosis and TLR4. In the present study, we showed that TNF-α increased the expression of TLR4, which promoted osteocyte necroptosis in PMOP. In patients with PMOP, TLR4 was highly expressed at skeletal sites where exists osteocyte necroptosis, and high TLR4 expression is correlated with enhanced TNF-α expression. Osteocytes exhibited robust TLR4 expression upon exposure to necroptotic osteocytes in vivo and in vitro. Western blotting and immunofluorescence analyses demonstrated that TNF-α upregulated TLR4 expression in vitro, which might further promote osteocyte necroptosis. Furthermore, inhibition of TLR4 by TAK-242 in vitro effectively blocked osteocyte necroptosis induced by TNF-α. Collectively, these results suggest a novel TLR4-mediated process of osteocyte necroptosis, which might increase osteocyte death and bone loss in the process of PMOP.


Assuntos
Osteócitos , Osteoporose Pós-Menopausa , Receptor 4 Toll-Like , Fator de Necrose Tumoral alfa , Feminino , Humanos , Necroptose , Osteócitos/metabolismo , Osteoporose Pós-Menopausa/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
2.
Glob Chang Biol ; 30(1): e17091, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273482

RESUMO

Drylands are important carbon pools and are highly vulnerable to climate change, particularly in the context of increasing aridity. However, there has been limited research on the effects of aridification on soil total carbon including soil organic carbon and soil inorganic carbon, which hinders comprehensive understanding and projection of soil carbon dynamics in drylands. To determine the response of soil total carbon to aridification, and to understand how aridification drives soil total carbon variation along the aridity gradient through different ecosystem attributes, we measured soil organic carbon, inorganic carbon and total carbon across a ~4000 km aridity gradient in the drylands of northern China. Distribution patterns of organic carbon, inorganic carbon, and total carbon at different sites along the aridity gradient were analyzed. Results showed that soil organic carbon and inorganic carbon had a complementary relationship, that is, an increase in soil inorganic carbon positively compensated for the decrease in organic carbon in semiarid to hyperarid regions. Soil total carbon exhibited a nonlinear change with increasing aridity, and the effect of aridity on total carbon shifted from negative to positive at an aridity level of 0.71. In less arid regions, aridification leads to a decrease in total carbon, mainly through a decrease in organic carbon, whereas in more arid regions, aridification promotes an increase in inorganic carbon and thus an increase in total carbon. Our study highlights the importance of soil inorganic carbon to total carbon and the different effects of aridity on soil carbon pools in drylands. Soil total carbon needs to be considered when developing measures to conserve the terrestrial carbon sink.


Assuntos
Ecossistema , Solo , Carbono/análise , Clima Desértico , China
3.
J Environ Manage ; 343: 118186, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224686

RESUMO

Driven by the goal of reversing desertification and recovering degraded lands, a wide range of vegetation restoration practices (such as planting and fencing) have been implemented in China's drylands. It is essential to examine the effects of vegetation restoration and environmental factors on soil nutrients to optimize restoration approaches. However, quantitative evaluation on this topic is insufficient due to a lack of long-term field monitoring data. This study evaluated the effects of sandy steppe restoration and sand dune fixation in the semi-arid desert, and natural and artificial vegetation restoration in the arid desert. It considered soil and plant characteristics using long-term (2005-2015) data from the Naiman Research Station located in the semi-arid region and Shapotou Research Station in the arid region of China's drylands. Results showed the sandy steppe had higher soil nutrient contents, vegetation biomass and rate of accumulating soil organic matter (OM) than the fixed dunes and moving dunes. Soil nutrient contents and vegetation biomass of the natural vegetation of Artemisia ordosica were higher than those of the artificial restoration of Artemisia ordosica since 1956. Artificial restoration had a higher rate of accumulating soil OM, total nitrogen (TN) and grass litter biomass than natural restoration. Soil water indirectly affected soil OM by affecting vegetation. Grass diversity was the main influencing factor on soil OM variance in the semi-arid Naiman desert while shrub diversity was the main factor in the arid Shapotou desert. These findings indicate that sand fixation in the semi-arid desert and vegetation restoration in the arid desert bring benefits for soil nutrient accumulation and vegetation improvement, and that natural restoration is preferable to artificial restoration. Results can be used to formulate sustainable vegetation restoration strategies, such as encouraging natural restoration, considering local resource constraints, and giving priority to restoring shrubs in arid areas with limited water.


Assuntos
Ecossistema , Solo , Areia , Poaceae , China , Clima Desértico , Água
4.
Sci Total Environ ; 877: 162946, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36948320

RESUMO

Dryland soils are nutrient-poor and prone to degradation due to aridity, grazing and enclosure. It is essential to examine the effects of grazing and enclosure on aridity-induced soil degradation in dryland ecosystems to optimize land management practices in response to climate change. However, quantitative evaluation on this topic is scarce due to a lack of long-term field monitoring data. This study evaluated the combined effects of aridity and grazing/enclosure using long-term data (2005-2015) from three research stations on soil physical and chemical properties in typical steppes and desert steppes across the semi-arid and hyper-arid areas of China's drylands. Results showed that soil organic matter (OM) content was higher for enclosures (20.50 g/kg) than for grazing (19.06 g/kg). In the semi-arid steppe, enclosures aged 30-33 years had the highest soil total nitrogen (TN) content (1.21 g/kg). Longer enclosures aged 34-36 years showed decreased soil TN content (0.88 g/kg). In the desert steppe, enclosures aged 5-8 years exhibited the highest soil OM (2.44 g/kg) and TN (0.21 g/kg) contents. Grazing enhanced the decrease of OM content (from 4.57 to 2.39 g/kg) with increasing aridity (1 - aridity index) from 0.35 to 1. These findings indicate that enclosures can improve soil fertility, but prolonged enclosures may have negative effects. Grazing had a synergistic effect on the decrease of OM with aridity. Results can be used in response to climate changes to formulate sustainable land management strategies, such as reducing the enclosure period in wetter and restored areas, and diminishing the grazing intensity in areas with higher aridity.

5.
Sci Bull (Beijing) ; 68(4): 424-435, 2023 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-36732118

RESUMO

Synergistically maintain or enhance the numerous beneficial contributions of nature to the quality of human life is an important but challenging question for achieving Sustainable Development Goals. However, the spatiotemporal distributions of global nature's contributions to people (NCPs) and their interactions remain unclear. We built a rapid assessment indicator framework and produced the first spatially explicit assessment of all 18 NCPs at a global scale. The 18 global NCPs in 1992 and 2018 were globally assessed in 15,204 subbasins based on two spatial indicator dimensions, including nature's potential contribution and the actual contribution to people. The results show that most of the high NCP values are highly localized. From 1992 to 2018, 6 regulating NCPs, 3 material NCPs, and 2 nonmaterial NCPs declined; 29 regulating-material NCP combinations (54 in total) dominated 76% of the terrestrial area, and the area with few NCPs accounted for 22%; and synergistic relationships were more common than tradeoff relationships, while the relationships among regulating and material NCPs generally traded-off with each other. Transitional climate areas contained few NCPs and have strong tradeoff relationships. However, the high synergistic relationship among NCPs in low latitudes could be threatened by future climate change. These findings provide a general spatiotemporal understanding of global NCP distributions and can be used to interpret the biogeographic information in a functional way to support regional coordination and achieve landscape multifunctionality for the enhancement of human well-being.


Assuntos
Mudança Climática , Desenvolvimento Sustentável , Humanos
6.
Sci Bull (Beijing) ; 68(2): 224-232, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36681590

RESUMO

Drylands cover about 40% of the terrestrial surface and are sensitive to climate change, but their relative contributions to global vegetation greening and productivity increase in recent decades are still poorly known. Here, by integrating satellite data and biosphere modeling, we showed that drylands contributed more to global gross primary productivity (GPP) increase (65% ± 16%) than to Earth greening (33% ± 15%) observed during 1982-2015. The enhanced productivity per unit leaf area, i.e., light-use efficiency (LUE), was the mechanism behind this pattern. We also found that LUE was more sensitive to soil moisture than to atmospheric vapor pressure deficit (VPD) in drylands, while the opposite was observed (i.e., LUE was more sensitive to VPD) in humid areas. Our findings suggest the importance of using different moisture stress metrics in projecting the vegetation productivity changes of dry versus humid regions and highlight the prominent role of drylands as key controllers of the global carbon cycle.

7.
Int J Colorectal Dis ; 37(9): 1925-1935, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35934748

RESUMO

OBJECTIVE: A meta-analysis of the relevant literature evaluated the feasibility, safety, and potential benefits of single-incision laparoscopic appendectomy (SILA) relative to those of conventional laparoscopic appendectomy (CLA). METHODS: The major biomedical databases, including ClinicalTrials.gov, were searched up to January 2022 for relevant randomized controlled trials (RCTs). SILA and CLA were compared regarding patient body mass index, operative time, and perioperative complications. The Cochrane Handbook and RevMan 5.3 were used to judge trial quality and perform the meta-analysis, respectively. RESULTS: The 17 included RCTs comprised 2068 patients, of whom 1039 and 1029 patients underwent SILA and CLA, respectively. The operative time for SILA was longer than that for CLA (MD = 8.35 min, 95% CI = 6.58 to 10.11, P < 0.00001), but the cosmetic results from SILA were superior (SMD = 0.81, 95% CI = 0.58 to 1.03, P < 0.00001). However, the incidence rates were similar in terms of patient body mass index; postoperative pain scores; and rates of abdominal abscess, conversion to open surgery, ileus, surgical site infection, and overall perioperative complications between the two groups. CONCLUSION: SILA is a safe technique for acute appendicitis, and its cosmetic outcomes are superior to those of CLA.


Assuntos
Apendicite , Laparoscopia , Doença Aguda , Apendicectomia/efeitos adversos , Apendicectomia/métodos , Apendicite/cirurgia , Conversão para Cirurgia Aberta , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Tempo de Internação , Duração da Cirurgia , Resultado do Tratamento
8.
J Environ Manage ; 313: 114896, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35390651

RESUMO

The evaluation of regional water resource carrying capacity has been repeatedly conducted to provide a scientific basis for the local water resource management and the sustainable development, in particular in the water-limited regions. However, the definition of regional water resource carrying capacity and its evaluation method are still arguable. Through a case study of Inner Mongolia, located in the arid and semi-arid northern China, this paper developed an improved method to calculate regional water resource carrying capacity by the combination of the water supply-demand analysis and the S-shaped curve threshold analysis. The spatial and temporal patterns of the regional water resource carrying capacity in Inner Mongolia during 2000-2019 was evaluated at three scales, namely the province scale, the basin scale and the city scale. The results showed that the average regional water resource carrying capacity of the whole province was 0.25 (the full mark is 1.00); at the basin scale, the Yellow River Basin had the lowest regional water resource carrying capacity (0.17) among all the basins, showing that the utilization of the water resources was unreasonable; at the city scale, the average regional water resource carrying capacities in Hulunbuir and Xilingol were both over 0.25, while those in Alxa, BayanNur and Wuhai were below 0.1; Hulunbuir had 25.48 billion m3 water surplus, while BayanNur suffered from an average water deficit of 4.51 billion m3 from 2000 to 2019. This paper has provided a reasonable way to measure the regional water resource carrying capacity using an improved method by incorporating S-shaped curve threshold analysis, which may have a wider application for the clustering and optimization of regional water management. In addition, the spatial and temporal patterns of regional water carrying capacity are beneficial for policymakers in the implementation of the effective water usage.


Assuntos
Conservação dos Recursos Naturais , Recursos Hídricos , China , Desenvolvimento Sustentável , Água
9.
Environ Res ; 197: 111087, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33798514

RESUMO

Soil erosion can present a major threat to agriculture due to loss of soil, nutrients, and organic carbon. Therefore, soil erosion modelling is one of the steps used to plan suitable soil protection measures and detect erosion hotspots. A bibliometric analysis of this topic can reveal research patterns and soil erosion modelling characteristics that can help identify steps needed to enhance the research conducted in this field. Therefore, a detailed bibliometric analysis, including investigation of collaboration networks and citation patterns, should be conducted. The updated version of the Global Applications of Soil Erosion Modelling Tracker (GASEMT) database contains information about citation characteristics and publication type. Here, we investigated the impact of the number of authors, the publication type and the selected journal on the number of citations. Generalized boosted regression tree (BRT) modelling was used to evaluate the most relevant variables related to soil erosion modelling. Additionally, bibliometric networks were analysed and visualized. This study revealed that the selection of the soil erosion model has the largest impact on the number of publication citations, followed by the modelling scale and the publication's CiteScore. Some of the other GASEMT database attributes such as model calibration and validation have negligible influence on the number of citations according to the BRT model. Although it is true that studies that conduct calibration, on average, received around 30% more citations, than studies where calibration was not performed. Moreover, the bibliographic coupling and citation networks show a clear continental pattern, although the co-authorship network does not show the same characteristics. Therefore, soil erosion modellers should conduct even more comprehensive review of past studies and focus not just on the research conducted in the same country or continent. Moreover, when evaluating soil erosion models, an additional focus should be given to field measurements, model calibration, performance assessment and uncertainty of modelling results. The results of this study indicate that these GASEMT database attributes had smaller impact on the number of citations, according to the BRT model, than anticipated, which could suggest that these attributes should be given additional attention by the soil erosion modelling community. This study provides a kind of bibliographic benchmark for soil erosion modelling research papers as modellers can estimate the influence of their paper.


Assuntos
Bibliometria , Erosão do Solo , Agricultura , Publicações , Solo
10.
Sci Total Environ ; 780: 146494, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773346

RESUMO

To gain a better understanding of the global application of soil erosion prediction models, we comprehensively reviewed relevant peer-reviewed research literature on soil-erosion modelling published between 1994 and 2017. We aimed to identify (i) the processes and models most frequently addressed in the literature, (ii) the regions within which models are primarily applied, (iii) the regions which remain unaddressed and why, and (iv) how frequently studies are conducted to validate/evaluate model outcomes relative to measured data. To perform this task, we combined the collective knowledge of 67 soil-erosion scientists from 25 countries. The resulting database, named 'Global Applications of Soil Erosion Modelling Tracker (GASEMT)', includes 3030 individual modelling records from 126 countries, encompassing all continents (except Antarctica). Out of the 8471 articles identified as potentially relevant, we reviewed 1697 appropriate articles and systematically evaluated and transferred 42 relevant attributes into the database. This GASEMT database provides comprehensive insights into the state-of-the-art of soil- erosion models and model applications worldwide. This database intends to support the upcoming country-based United Nations global soil-erosion assessment in addition to helping to inform soil erosion research priorities by building a foundation for future targeted, in-depth analyses. GASEMT is an open-source database available to the entire user-community to develop research, rectify errors, and make future expansions.

11.
Ren Fail ; 39(1): 678-687, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28853301

RESUMO

BACKGROUND: Total parathyroidectomy (tPTX) and total parathyroidectomy with autotransplantation (tPTX + AT) are effective and inexpensive treatments for secondary hyperparathyroidism (sHPT), but we do not know which one is the optimal approach. Therefore, we undertook a meta-analysis to compare the safety and efficacy of these two surgical procedures. METHODOLOGY: Studies published in English on PubMed, Embase and the Cochrane Library from inception to 27 September 2016 were searched systematically. Eligible studies comparing tPTX with tPTX + AT for sHPT were included and Review Manager v5.3 was used. RESULTS: Eleven studies were included in this meta-analysis. Ten cohort studies and one randomized controlled trial (RCT) involving 1108 patients with sHPT were identified. There was no significant difference in the prevalence of surgical complications (relative risk [RR], 1.71; 95% confidence interval [CI], 0.77-3.79; p = .19), all-cause mortality (RR, 0.68; 95% CI, 0.33-1.39; p = .29), sHPT persistence (RR, 3.81; 95% CI, 0.56-25.95; p = .17) or symptomatic improvement (RR, 1.02; 95% CI, 0.91-1.13; p = .79). tPTX could reduce the risk of sHPT recurrence (RR, 0.19; 95% CI, 0.09-0.41; p < .0001) and reoperation because of recurrence or persistence of sHPT (RR, 0.46; 95% CI 0.24-0.86; p = .01) compared with tPTX + AT. Simultaneously, tPTX increased the risk of hypoparathyroidism (RR, 2.63; 95% CI, 1.06-6.51; p = .04). CONCLUSIONS: We found tPTX and tPTX + AT to be useful methods for sHPT treatment. tPTX was superior for reducing the risk of sHPT recurrence and reoperation than tPTX + AT but, due to a lack of high statistical-power RCTs, comparative studies will be needed in the future.


Assuntos
Hiperparatireoidismo Secundário/cirurgia , Paratireoidectomia/estatística & dados numéricos , Humanos , Paratireoidectomia/métodos , Reoperação , Transplante Autólogo
12.
Int J Environ Res Public Health ; 9(6): 2226-40, 2012 06.
Artigo em Inglês | MEDLINE | ID: mdl-22829800

RESUMO

China's industry accounts for 46.8% of the national Gross Domestic Product (GDP) and plays an important strategic role in its economic growth. On the other hand, industrial wastewater is also the major source of water pollution. In order to examine the relationship between the underlying driving forces and various environmental indicators, values of two critical industrial wastewater pollutant discharge parameters (Chemical Oxygen Demand (COD) and ammonia nitrogen (NH(4)-N)), between 2001 and 2009, were decomposed into three factors: i.e., production effects (caused by change in the scale of economic activity), structure effects (caused by change in economic structure) and intensity effects (caused by change in technological level of each sector), using additive version of the Logarithmic Mean Divisia Index (LMDI I) decomposition method. Results showed that: (1) the average annual effect of COD discharges in China was -2.99%, whereas the production effect, the structure effect, and the intensity effect were 14.64%, -1.39%, and -16.24%, respectively. Similarly, the average effect of NH(4)-N discharges was -4.03%, while the production effect, the structure effect, and the intensity effect were 16.18%, -2.88%, and -17.33%, respectively; (2) the production effect was the major factor responsible for the increase in COD and NH(4)-N discharges, accounting for 45% and 44% of the total contribution, respectively; (3) the intensity effect, which accounted for 50% and 48% of the total contribution, respectively, exerted a dominant decremental effect on COD and NH(4)-N discharges; intensity effect was further decomposed into cleaner production effect and pollution abatement effect with the cleaner production effect accounting for 60% and 55% of the reduction of COD and NH(4)-N, respectively; (4) the major contributors to incremental COD and NH(4)-N discharges were divided among industrial sub-sectors and the top contributors were identified. Potential restructuring and regulation measures were proposed for pollutant reduction.


Assuntos
Amônia/análise , Análise da Demanda Biológica de Oxigênio/estatística & dados numéricos , Resíduos Industriais/análise , Águas Residuárias/análise , Poluentes da Água/análise , Poluição da Água/análise , China
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