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2.
Environ Sci Pollut Res Int ; 30(56): 119434-119449, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924405

RESUMEN

The carbon emissions trading scheme (CETS) in China is an important market-based environmental policy mechanism for decreasing carbon emissions. This paper calculates the total factor carbon productivity (TFCP) based on data from 275 cities in China from 2007 to 2020 using the DEA method and investigates the impact of the CETS on regional TFCP using the differences-in-differences (DID) method, all against the backdrop of carbon peaking and carbon neutrality. The research findings reveal that CETS has consistently improved TFCP in pilot cities, and this conclusion has held up following a number of robustness tests. Temporal heterogeneity experiments demonstrate that as implementation time increases, the enhancing effect takes on an inverted "U-shaped" structure with a 7-year effective lifetime. Spatial heterogeneity studies reveal that as one moves away from the pilot cities, the policy effect on surrounding cities' TFCP is inhibited, followed by facilitation. CETS policies can influence regional TFCP through the effects of green innovation and industry upgrading, according to mediation mechanism testing. We present policy recommendations based on the research findings for meeting the "dual" carbon goals and strengthening the carbon trading mechanism.


Asunto(s)
Carbono , Política Ambiental , China , Ciudades , Industrias , Desarrollo Económico
3.
Plant Physiol Biochem ; 204: 108097, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37864930

RESUMEN

Salt stress adversely affects the growth, development, and yield of tomato (Solanum lycopersicum). SAM Synthetase (SAMS), which is responsible for the biosynthesis of S-adenosylmethionine (SAM, a precursor of polyamine biosynthesis), participates in plant response to abiotic stress. However, the regulatory mechanism of SAMS-mediated salt stress tolerance remains elusive. In this study, we characterized a SAMS homologue SlSAMS1 in tomato. We found that SlSAMS1 is highly expressed in tomato roots, and its expression can be induced by salt stress. Crucially, overexpression of SlSAMS1 in tomato enhances salt stress tolerance. Through metabolomic profiling, we identified some differentially accumulated metabolites, especially, a secondary messenger guanosine 3',5'-cyclic monophosphate (cGMP) which may play a key role in SlSAMS1-regulated salt tolerance. A series of physiological and biochemical data suggest that cGMP alleviates salt stress-induced growth inhibition, and potentially acts downstream of the polyamine-nitric oxide (PA-NO) signaling pathway to trigger H2O2 signaling in response to salt stress. Taken together, the study reveals that SlSAMS1 regulates tomato salt tolerance via the PA-NO-cGMP-H2O2 signal module. Our findings elucidate the regulatory pathway of SlSAMS1-induced plant response to salt stress and indicate a pivotal role of cGMP in salt tolerance.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Tolerancia a la Sal/genética , Peróxido de Hidrógeno/metabolismo , Estrés Fisiológico , S-Adenosilmetionina/metabolismo , Poliaminas/metabolismo , Regulación de la Expresión Génica de las Plantas
4.
J Ocean Univ China ; 21(4): 1027-1036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35757191

RESUMEN

Toll like receptors (TLRs) are the main innate immune 'pattern recognition receptors' of animals, which play a central role in host cell recognition and responses to invasive pathogens, particularly common structures of microbial pathogens. In this study, the gene expression profiles of TLRs in the spleen, head kidney, gill, small intestine, liver, muscle, and heart of healthy Paralichthys olivaceus were detected by real-time quantitative PCR (qPCR). The TLR family members were widely expressed in different tissues with different basic expression profiles. The highest expressions of TLR1, 5m, 7, 8, 9, 14, and 21 were found in the spleen; the highest expressions of TLR3 and TLR21 were found in the gill; the highest expressions of TLR2 and 5s were found in the small intestine. The second highest expressions of TLR3, 7, and 8 were found in small intestine. The gene expression profiles of TLRs stimulated with Edwardsiella tarda DNA, RNA, and lipopolysaccharide (LPS) were also detected in spleen, head kidney and gill. TLR9 and TLR21 were sensitive to E. tarda DNA; TLR 8 and TLR21 were sensitive to E. tarda RNA; and TLR1 and TLR14 were sensitive to E. tarda LPS. The expressions of the other TLR genes showed no significant changes. The results imply that the expressions of these TLR genes in P. olivaceus are differently regulated in the whole body and play important roles in the immune response against E. tarda infection.

5.
Onco Targets Ther ; 12: 8339-8353, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31686859

RESUMEN

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a highly aggressive malignancy. The aims of the present study were to screen the critical miRNA and corresponding target genes that related to development of ESCC by weighted gene correlation network analysis (WGCNA) and investigate the functions by experimental validation. METHODS: Datasets of mRNA and miRNA expression data were downloaded from GEO. The R software was used for data preprocessing and differential expression gene analysis. The differentially expressed protein-coding genes (DEGs) and miRNAs (DEMs) were selected (FDR <0.05 or |Fold Change (FC)| >1.5). Meanwhile, 81 expression data of ESCC patients in TCGA combined with clinic information were applied by WGCNA to create networks. The correlational analyses between each module and clinical parameters were conducted, and enrichment analyses of GO and KEGG were subsequently performed. Then, a series of experiments were conducted in ESCC cells by use of miRNA mimics. RESULTS: In total, 4,023 DEGs and 328 DEMs were screened. After checking good genes and samples, 3,841 genes (3,696 DEGs and 145 DEMs) were used for WGCNA. As a consequence, altogether 11 gene modules were found. Among them, the brown modules were found to be strongly inversely associated with pathological grade. Meanwhile, has-mir-92b, the only miRNA in brown module, had a positive correlation with grade and negatively correlated with potential target gene (KFL4 and DCS2) in the same module. Furthermore, an increased expression of miR-92b-3p and down-regulated KLF4 and DSC2 protein was detected in the ESCC clinical samples. Up-regulated miR-92b-3p shortened G0/G1 phase and promote ESCC cells invasion and migration. Furthermore, we verified that DSC2 and KFL4 was target genes of miR-92b-3p by luciferase report assay. CONCLUSION: WGCNA is an efficient approach to system biology. By this procedure, miR-92b-3p was identified as an ESCC-promoting gene by target KLF4 and DCS2.

6.
Sensors (Basel) ; 19(17)2019 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-31480349

RESUMEN

Due to multi-factor coupling behavior, the performance evaluation of an accelerometer subject to high-temperature and high-impact loads poses a significant challenge during its design phase. In this paper, the simulation-based method is applied to optimize the design of the accelerometer. The proposed method can reduce the uncertainties and improve the fidelity of the simulation in the sense that (i) the preloading conditions of fasteners are taken into consideration and modeled in static analysis; (ii) all types of loadings, including bolt preloads, thermal loads, and impact loads, are defined in virtual dynamic prototype of the accelerometer. It is our finding that from static and dynamic analysis, an accelerometer is exposed to the risk of malfunction and even a complete failure if the temperature rises to a certain limit; it has been proved that the thermal properties of sensing components are the most critical factors for an accelerometer to achieve its desired performance. Accordingly, we use a simulation-based method to optimize the thermal expansion coefficient of the sensing element and get the expected design objectives.

7.
Saudi J Gastroenterol ; 25(2): 113-118, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30588952

RESUMEN

BACKGROUND/AIM: The dramatic color change after iodine staining (from white-yellow to pink after 2-3 min), designated as the "pink-color sign" (PCS), is indicative of esophageal high-grade intraepithelial neoplasia (HGIN) or an invasive lesion. However, no study has yet examined the association between the time of PCS appearance and histopathology. We investigated the association between the time of PCS appearance and esophageal histopathology in 456 lesions of 438 patients who were examined for suspected esophageal cancer. MATERIALS AND METHODS:: The records of 495 consecutive patients who had suspected esophageal cancer based on gastroscopy and who underwent Lugol's chromoendoscopy from January 2015 to March 2018 were retrospectively reviewed. The time of PCS appearance was recorded in all patients, and tissue specimens were examined. RESULTS: We examined 456 lesions in 438 patients. Use of PCS positivity at 2 min for the diagnosis of HGIN/invasive cancer had a sensitivity of 84.1%, a specificity of 72.7%, and an accuracy of 80.4%. We classified the PCS-positive patients in whom the time of PCS appearance was recorded (168 lesions) into 4 groups: 0-30, 31-60, 61-90, and 91-120 s. Based on a 60-s time for appearance of the PCS, the area under the receiver operating characteristic curve was 0.897, indicating good validity. At the optimal cutoff value of 60 s, the sensitivity was 90.2% and the specificity was 82.3%. The appearance of the PCS within 60 s had a diagnostic accordance rate of 88.6%, significantly higher than appearance of the PCS within 2 min (79.7%, P < 0.05). CONCLUSION: Appearance of the PCS within 1 min after iodine staining has a higher diagnostic accordance rate for esophageal HGIN/invasive cancer than appearance of the PCS at 2 min.


Asunto(s)
Carcinoma in Situ/patología , Neoplasias Esofágicas/patología , Esófago/patología , Yodo/metabolismo , Invasividad Neoplásica/patología , Coloración y Etiquetado/métodos , Adulto , Anciano , Anciano de 80 o más Años , Colorantes , Neoplasias Esofágicas/diagnóstico por imagen , Femenino , Gastroscopía/métodos , Humanos , Yoduros/economía , Yoduros/metabolismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad , Coloración y Etiquetado/estadística & datos numéricos
8.
Yao Xue Xue Bao ; 51(2): 316-24, 2016 Feb.
Artículo en Chino | MEDLINE | ID: mdl-29856587

RESUMEN

A large number of experimental and clinical data indicates that tumor-associated macrophages(TAMs) were involved in the whole process of tumor growth, invasion and metastasis. Like macrophages in other tissues, TAMs originate from blood monocytes, which are recruited to the tumor tissues by cytokines and then differentiated into TAMs. It is interesting that the monocytes overexpress siglec receptor in their surface, which has a high binding specificity to sialic acid(SA). From this point of view, we hypothesize that if SA was used as a ligand in the surfaces of drug delivery systems, SA would enhance the targeting efficiency to monocytes, and thus to achieve a higher specificity to TAMs. In our previous study, an SA derivative of SA-octadecylamine(SA-18) was synthesized and was found to enhance cytotoxicity on TAMs in vitro. The chain length is a critical factor for SA efficiency in liposomes and it has a significant influence on the TAM targeting effects of the carriers. So in this study, four kinds of different chain length of SA fatty amine derivatives were synthesized, including SA-18, SA-hexadecylamine(SA-16), SA-tetradecylamine(SA-14) and SA-dodecylamine(SA-12), and were modified on the surfaces of blank liposomes(BLK-Sn L, n = 18, 16, 14, 12) and pixantrone maleate-loaded liposomes(Pix-Sn L, n = 18, 16, 14, 12). TAM targeting effects of these SA derivatives were evaluated by acute toxicity and antitumor efficacy in vivo. The results of acute toxicity experiments showed that the toxicities of the SA derivatives deceased gradually with the reduction in the length of lipophilic chain. The in vivo antitumor efficacies of SA-modified blank liposomes showed that these blank formulations had no effect on the tumor inhibition except BLK-S14L(61.4% ± 18.8%), and BLK-S16 L even promoted the tumor growth(-31.7% ± 13.1%, the 18 th day). The in vivo antitumor efficacies of SA-modified Pix liposomes showed that the tumor inhibition effects were Pix-S18L(97.4% ± 2.1%) > Pix-S14L(73.1% ±21.1%) > Pix-S12L(53.9% ± 17.8%) > Pix-S16L(32.9%). Because of the relatively strong binding ability of SA-18, it was hard to fall off from the liposomes in the transport process, leading to a good TAM targeting ability and less toxicity to the normal tissues. Meanwhile, 50% of the mice in Pix-S18 L group showed "tumor shedding" and "wound healing" phenomena without recurrence in two months following the treatment. Therefore, SA-18 is the most potential TAM targeting material among these SA fatty amine derivatives.


Asunto(s)
Sistemas de Liberación de Medicamentos , Liposomas , Macrófagos/efectos de los fármacos , Ácido N-Acetilneuramínico/química , Neoplasias/tratamiento farmacológico , Aminas , Animales , Línea Celular Tumoral , Composición de Medicamentos , Humanos , Hidrocarburos , Ratones
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