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1.
Glob Chang Biol ; 26(6): 3738-3751, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32239592

RESUMO

Intensive crop production systems worldwide, particularly in China, rely heavily on nitrogen (N) fertilization, but left more than 50% of fertilizer N in the environment. Nitrogen (over) fertilization and atmospheric N deposition induce soil acidification, which is neutralized by soil inorganic carbon (SIC; carbonates), and carbon dioxide (CO2 ) is released to the atmosphere. For the first time, the loss of SIC stocks in response to N-induced soil acidification was estimated for Chinese croplands from 1980 to 2020 and forecasts were made up to 2100. The SIC stocks in croplands in 1980 were 2.16 Pg C (16.3 Mg C/ha) in the upper 40 cm, 7% (0.15 Pg C; 1.1 Mg C/ha) of which were lost from 1980 to 2020. During these 40 years, 7 million ha of cropland has become carbonate free. Another 37% of the SIC stocks may be lost up to 2100 in China, leaving 30 million ha of cropland (37.8%) without carbonates if N fertilization follows the business-as-usual (BAU) scenario. Compared to the BAU scenario, the reduction in N input by 15%-30% after 2020 (scenarios S1 and S2) will decrease carbonate dissolution by 18%-41%. If N input remains constant as noted in 2020 (S3) or decreases by 1% annually (S4), a reduction of up to 52%-67% in carbonate dissolution is expected compared to the BAU scenario. The presence of CaCO3 in the soil is important for various processes including acidity buffering, aggregate formation and stabilization, organic matter stabilization, microbial and enzyme activities, nutrient cycling and availability, and water permeability and plant productivity. Therefore, optimizing N fertilization and improving N-use efficiency are important for decreasing SIC losses from acidification. N application should be strictly calculated based on crop demand, and any overfertilization should be avoided to prevent environmental problems and soil fertility decline associated with CaCO3 losses.


Assuntos
Nitrogênio , Solo , Agricultura , China , Produtos Agrícolas , Fertilizantes , Concentração de Íons de Hidrogênio
2.
Melanoma Res ; 34(3): 225-233, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38469881

RESUMO

Currently, numerous studies suggest a potential association between the gut microbiota and the progression of melanoma. Hence, our objective was to examine the genetic impact of the gut microbiota on melanoma through the utilization of the Mendelian randomization (MR) approach. This research employed Bacteroides, Streptococcus, Proteobacteria, and Lachnospiraceae as exposure variables and cutaneous melanoma (CM) as the outcome in a two-sample MR analysis. In this MR research, the primary analytical approach was the random-effects inverse-variance weighting (IVW) model. Complementary methods included weighted median, MR Egger, and basic and weighted models. We assessed both heterogeneity and horizontal pleiotropy in our study, scrutinizing whether the analysis results were affected by any individual SNP. The random-effects IVW outcomes indicated that Streptococcus, Bacteroides, Lachnospiraceae and Proteobacteria had no causal relationship with CM, with odds ratios of 1.001 [95% confidence interval (CI) = 0.998-1.004, P  = 0.444], 0.999 (95% CI = 0.996-1.002, P  = 0.692), 1.001 (95% CI = 0.998-1.003, P  = 0.306), and 0.999 (95% CI = 0.997-1.002, P  = 0.998), respectively. No analyses exhibited heterogeneity, horizontal pleiotropy, or deviations. Our research determined that Bacteroides, Streptococcus, Proteobacteria, and Lachnospiraceae do not induce CM at the genetic level. However, we cannot dismiss the possibility that these four gut microbiotas might influence CM through other mechanisms.


Assuntos
Microbioma Gastrointestinal , Melanoma , Análise da Randomização Mendeliana , Neoplasias Cutâneas , Humanos , Melanoma/genética , Melanoma/microbiologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/microbiologia , Melanoma Maligno Cutâneo
3.
Laryngoscope ; 134(8): 3572-3580, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38421050

RESUMO

HYPOTHESIS: Unilateral costal cartilage harvesting (UCCH) for auricle reconstruction in children tends to cause thoracic deformities. Therefore, our study aimed to develop a novel bilateral costal cartilage harvesting (BCCH) method to prevent and reduce thoracic deformities. METHODS: Patients with unilateral microtia who underwent either UCCH (n = 50) or BCCH (n = 46) were enrolled in this study. The grafts for the BCCH group were harvested from the 6th costal cartilage of the ipsilateral hemithorax and the 7th and 8th cartilage from the other hemithorax. Computed tomography and physical examination were performed to identify any physical deformities in the chest contours post-surgery. The cosmetic appearance of the thoracic scars post-surgery was evaluated using the Scar Cosmesis Assessment and Rating Scale (SCAR) and Visual Analogue Scales (VAS cosmetic). The numerical rating scale (NRS) was used to quantify the pain in donor sites. The reconstructed ears were assessed during the follow-up period. RESULT: None of the patients in the BCCH group developed thoracic deformities, while 16 patients within the UCCH group developed mild (n = 12) or severe (n = 4) thoracic deformities (p < 0.001). The SCAR (3.09 vs. 2.92, p = 0.580) and VAS scores (0.96 vs. 0.90, p = 0.813) did not differ significantly between the two groups. For both treatment arms, the NRS scores were highest on the first-day post-surgery and gradually dropped over the 10 days. No significant differences were found in the NRS scores and the aesthetic outcomes of the reconstructed ears between the two groups. CONCLUSION: The BCCH method effectively reduced the incidence of thoracic deformity at the donor site without increasing postoperative pain and cosmetic concerns for patients. It could be used clinically to improve patient outcomes of costal cartilage grafts. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3572-3580, 2024.


Assuntos
Microtia Congênita , Cartilagem Costal , Procedimentos de Cirurgia Plástica , Coleta de Tecidos e Órgãos , Humanos , Cartilagem Costal/transplante , Masculino , Feminino , Procedimentos de Cirurgia Plástica/métodos , Microtia Congênita/cirurgia , Criança , Coleta de Tecidos e Órgãos/métodos , Adolescente , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Pavilhão Auricular/cirurgia , Pavilhão Auricular/anormalidades , Resultado do Tratamento , Cicatriz/prevenção & controle , Cicatriz/etiologia , Tórax
4.
Sci Total Environ ; 825: 154087, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35218836

RESUMO

The long-term stability of soil inorganic carbon (SIC) and its minimum contribution towards global C cycle has been challenged, as recent studies have showed rapid decreases in SIC stocks in intensive agricultural systems. However, the extent of SIC losses and its driving factors remains unclear. Here, we compared changes in SIC density (SICD) in Chinese croplands between the 1980s and 2010s. The SIC contents in 1980s were obtained from second national soil survey (n = 949) and published studies (n = 47). The SIC contents in 2010s were based on resampling of soil profiles from the same locations during 2019 and 2020 (n = 30), as well as data from published studies and national soil survey (n = 903). We found that Chinese croplands have lost 27-38% of SICD from the 0-40 cm soil layer and that the soil pH has decreased by 0.53 units over the past 30 years. These SIC losses increased with the ratio of precipitation (P) to potential evapotranspiration (PET) and most notably with nitrogen (N) fertilization. The SICD decreased greatly in humid and semiarid regions, and these losses were enhanced by high N fertilization rates; however, the SICD increased in very arid regions. This analysis demonstrates that the water balance and N fertilization are major drivers leading to dramatic losses of SICD in croplands and, consequently, to decreases in soil fertility and functions.


Assuntos
Carbono , Solo , Agricultura , Carbono/análise , China , Produtos Agrícolas , Nitrogênio/análise , Solo/química
5.
Genes (Basel) ; 9(6)2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29874840

RESUMO

Recently, microfluidic technologies have attracted an enormous amount of interest as potential new tools for a large range of applications including materials synthesis, chemical and biological detection, drug delivery and screening, point-of-care diagnostics, and in-the-field analysis. Their ability to handle extremely small volumes of fluids is accompanied by additional benefits, most notably, rapid and efficient mass and heat transfer. In addition, reactions performed within microfluidic systems are highly controlled, meaning that many advanced materials, with uniform and bespoke properties, can be synthesized in a direct and rapid manner. In this review, we discuss the utility of microfluidic systems in the synthesis of materials for a variety of biological applications. Such materials include microparticles or microcapsules for drug delivery, nanoscale materials for medicine or cellular assays, and micro- or nanofibers for tissue engineering.

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