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2.
ACS Omega ; 9(6): 7132-7142, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38371767

RESUMEN

The recovery of low-grade waste heat from power plants greatly benefits energy conservation and emission reduction during electricity generation, while the waste heat utilization directly from desulfurization slurry is a significantly promising method to deeply recover such low-grade energy and has been developed in practical application. However, the pipe materials are subjected to erosion and corrosion challenges due to the high level of solid compositions and the presence of harmful ions, such as Cl-1, which requires further evaluation under the condition of slurry heat exchange. The present study aimed at an experimental study on the erosion-corrosion characteristics of desulfurization slurry on three types of stainless steel, including type 304, 316L, and 2205. Both mass loss and micromorphology features were analyzed with possible mechanisms elucidated. The erosion-corrosion rate is weak at low temperatures, while the increase in the slurry temperature clearly promotes its rate. The influence of the temperature on the corrosion resistance of 304 is much greater than that of 2205. With an increase in duration time, the weight loss rate of stainless steel in the desulfurization slurry declines, and the changing trend of metal mass slightly slows down. The present study offers a better understanding of the erosion-corrosion behaviors of three types of stainless steel under flow and heat transfer conditions of a desulfurization slurry.

4.
ACS Omega ; 7(29): 25613-25624, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35910123

RESUMEN

Tar-rich coal has the potential to substitute the supply of oil-gas resources, which is abundant in China. The effective conversion of tar-rich coal into oil-gas products can promote coal utilization, reduce resource wastage, alleviate environmental pollution, and benefit carbon neutrality. Nevertheless, less work, if any, has been performed on the pyrolysis and mild oxidation behaviors of tar-rich coal in Northwestern China. The influences of limited oxygen addition and an extremely low heating rate on the micromorphology of the residual semi-coke are yet to be fully understood. Here, an experimental study on the pyrolysis and mild oxidation characteristics of tar-rich coal was conducted by the thermogravimetric analysis method, with further elucidation of the physical-chemical properties of the residual semi-coke. Experimental results show that an increase in the ultimate temperature of pyrolysis leads to a decline in the residue mass, while the mass loss from 500 to 550 °C presents the maximum elevation. Volatile matter is inclined to discharge from a certain direction, and the pores formed in various directions hold different possibilities. The organic components undergo both pyrolysis and slow oxidation with limited oxygen in the heating medium. Compared with an inert atmosphere, the mass loss under conditions of a small amount of O2 is brought forward but prolonged. Compared with a N2 atmosphere, the oxidation reactions of tar-rich coal are weakened in the presence of CO2. A large decrease in the heating rate exerts an unfavorable effect on the production of total volatiles. An extremely low heating rate possibly brings about a change in the mechanism of chemical bond cracking during pyrolysis. More pores can be yielded in tar-rich coal with an increase in the heating rate, and the morphology of the residual semi-coke after pyrolysis is susceptible to the heating rate. The present study offers an improved understanding of the pyrolysis characteristics of tar-rich coal as well as insights into the efficient utilization of tar-rich coal.

5.
Front Immunol ; 12: 690234, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34220849

RESUMEN

As an intermediate substance of the tricarboxylic acid cycle and a precursor substance of glutamic acid synthesis, the effect of alpha-ketoglutarate on growth and protein synthesis has been extensively studied. However, its prevention and treatment of pathogenic bacteria and its mechanism have not yet been noticed. To evaluate the effects of alpha-ketoglutarate on intestinal antioxidant capacity and immune response of Songpu mirror carp, a total of 360 fish with an average initial weight of 6.54 ± 0.08 g were fed diets containing alpha-ketoglutarate with 1% for 8 weeks. At the end of the feeding trial, the fish were challenged with Aeromonas hydrophila for 2 weeks. The results indicated that alpha-ketoglutarate supplementation significantly increased the survival rate of carp after infection with Aeromonas hydrophila (P < 0.05), and the contents of immune digestion enzymes including lysozyme, alkaline phosphatase and the concentration of complement C4 were markedly enhanced after alpha-ketoglutarate supplementation (P < 0.05). Also, appropriate alpha-ketoglutarate increased the activities of total antioxidant capacity and catalase and prevented the up-regulation in the mRNA expression levels of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1ß, interleukin-6, and interleukin-8 (P < 0.05). Furthermore, the mRNA expression levels of toll-like receptor 4 (TLR4), and nuclear factor kappa-B (NF-κB) were strikingly increased after infection with Aeromonas hydrophila (P < 0.05), while the TLR4 was strikingly decreased with alpha-ketoglutarate supplementation (P < 0.05). Moreover, the mRNA expression levels of tight junctions including claudin-1, claudin-3, claudin-7, claudin-11 and myosin light chain kinases (MLCK) were upregulated after alpha-ketoglutarate supplementation (P < 0.05). In summary, the appropriate alpha-ketoglutarate supplementation could increase survival rate, strengthen the intestinal enzyme immunosuppressive activities, antioxidant capacities and alleviate the intestinal inflammation, thereby promoting the intestinal immune responses and barrier functions of Songpu mirror carp via activating TLR4/MyD88/NF-κB and MLCK signaling pathways after infection with Aeromonas hydrophila.


Asunto(s)
Aeromonas hydrophila/patogenicidad , Antioxidantes/metabolismo , Carpas/microbiología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Inmunidad Innata/efectos de los fármacos , Mucosa Intestinal/microbiología , Ácidos Cetoglutáricos/farmacología , Aeromonas hydrophila/inmunología , Alimentación Animal , Animales , Carpas/crecimiento & desarrollo , Carpas/inmunología , Carpas/metabolismo , Suplementos Dietéticos , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/metabolismo , Infecciones por Bacterias Gramnegativas/microbiología , Interacciones Huésped-Patógeno , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Quinasa de Cadena Ligera de Miosina/genética , Quinasa de Cadena Ligera de Miosina/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Transducción de Señal , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
6.
Fish Shellfish Immunol ; 84: 280-289, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30291983

RESUMEN

The present study was conducted to determine the effect of dietary N-carbamoylglutamate (NCG) supplementation on the growth performance, antioxidant capability and immune responses of mirror carp (Cyprinus carpio) fed an arginine (Arg)-deficient diet. A total of 630 mirror carp (41.65 ±â€¯0.14 g) were fed diets (Arg 1.24% of the diet) that were supplemented with 0.50% Arg (control diet) or graded levels of NCG at 0 (Arg deficiency diet), 0.04%, 0.08%, 0.12%, 0.16% and 0.20% for 8 weeks. The results showed that, compared with the control diet, the Arg-deficient diet supplementation with 0 NCG (1) decreased the final body weight (FWB), the weight gain rate (WGR) or the protein efficiency ratio (PER) and increased the feed conversion ratio (FCR); (2) decreased the concentration of Arg and nitric oxide (NO) and the activity of total nitric oxide synthetase (T-NOS) in the plasma; (3) decreased the activities of superoxide dismutase (SOD) in the proximal intestine (PI), catalase (CAT) in the PI and distal intestine (DI), and glutathione peroxidase (GPx) in PI and mid-intestine (MI) and increased the concentration of malondialdehyde (MDA) in the PI, MI and DI; and (4) decreased the activity of lysozyme in the plasma, increased the relative mRNA expression of tumor necrosis factor-α (TNF-α), interleukin1ß (IL-1ß) and interleukin 8 (IL-8) in the PI, MI and DI, and decreased the relative mRNA expression of interleukin 10 (IL-10) in the PI and MI, and transforming growth factor ß2 (TGF-ß2) in the PI, MI and DI. Compared with the Arg deficient-diet supplementation with 0 NCG, (1) 0.12% or 0.16% NCG increased the FBW, WGR and PER, and 0.16% NCG increased the FCR; (2) 0.08%-0.20% NCG increased the concentration of Arg, NO and the activity of T-NOS; (3) 0.08% NCG increased the activities of SOD in the PI and MI, and 0.12% NCG increased activities of CAT and GPx in the PI, MI and DI; and (4) 0.04%-0.20% NCG increased the activity of lysozyme, 0.04%-0.20% NCG decreased the relative mRNA expression of TNF-α, IL-1ß and IL-8 in the PI and MI, and 0.04%-0.20% NCG increased the relative mRNA expression of IL-10 and TGF-ß2 in the PI and MI. The present results indicated that dietary 0.12% or 0.16% NCG improved the growth performance, feed utilization, intestinal antioxidant capacity and immune response of mirror carp fed an Arg-deficient diet.


Asunto(s)
Antioxidantes/metabolismo , Arginina/metabolismo , Carpas/fisiología , Glutamatos/metabolismo , Inmunidad Innata/efectos de los fármacos , Alimentación Animal/análisis , Animales , Arginina/deficiencia , Carpas/crecimiento & desarrollo , Carpas/inmunología , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Glutamatos/administración & dosificación , Inmunidad Innata/fisiología
7.
Transl Cancer Res ; 8(8): 2781-2790, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35117035

RESUMEN

BACKGROUND: To analyze the associated factors that affect the coloration of methylene blue (MB) in axillary lymph node dissection (ALND) of patients with breast cancer and to explore the tracer effect of MB in high axillary lymph node metastasis, to guide surgical treatment. METHODS: We recruited 170 patients who underwent ALND, all of them were injected MB before operation. We analyzed the relationships between the clinical factors of age, body mass index (BMI), molecular typing, TNM staging, neoadjuvant chemotherapy, injection time and position and the MB coloration by univariate and multivariate analyses. A total of 84 cases were selected for observation of the application value of MB during intervention involving the lymph nodes upper axillary vein. RESULTS: Of 170 cases, 138 cases (81.17%) were colored. Univariate analysis showed that significant differences were observed between differing BMI's (χ2=24.074, P<0.0001) and injection times (χ2=41.207, P<0.0001). Multivariate analysis showed that injection time (P=0.016) was the clinical factor associated with MB coloration. More than 60 minutes before surgery and MB injection, the possibility of methylene blue colored was 0.088 times higher than 10 minutes (P=0.010, 95% CI, 0.014, 0.554). MB was used to track the lymph node upper axillary vein with a sensitivity of 12.5%, a specificity of 100%, a false negative rate of 87.50%, and a false positive rate of 0; the kappa coefficient was 0.051 (χ2=0.679, P=0.404). CONCLUSIONS: Among the clinical factors, MB coloration was worse more than 60 minutes before ALND. Using the technology of MB color, lymph nodes can be clearly identified. It has great guiding value for the doctors who learn the operation initially. However, it is still prudent to use MB for high lymph node dissection.

8.
Exp Mol Pathol ; 98(2): 254-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25617527

RESUMEN

Triple negative breast cancer (TNBC) is a heterogeneous disease with higher rates of relapse and decreased overall survival in metastatic tumors. Due to its poor prognosis, it is necessary to identify effective biomarkers that are associated with tumor growth and metastasis. The leucine zipper/EF hand-containing transmembrane-1 (LETM1) protein, which is a mitochondrial inner membrane protein, can reduce mitochondrial biogenesis and ATP production. The expression levels of LETM1 were significantly increased in numerous human malignancies. However, the clinicopathological characteristics and prognostic value of LETM1 overexpression in TNBC remains unclear. LETM1 protein was detected in 107 TNBC, 42 ductal carcinoma in situ (DCIS) and 65 adjacent non-tumor breast tissues using immunohistochemical (IHC) staining. Immunofluorescence (IF) staining was also performed to detect the localization of LETM1 protein in MCF-7 BC cells. The correlations between LETM1 overexpression and clinicopathological features of TNBC were evaluated using Chi-squared test and Fisher's exact tests. The survival rate was calculated using the Kaplan-Meier method. LETM1 protein showed cytoplasmic staining patterns in TNBC. The strongly positive rate of LETM1 in TNBC was 69.2% (74/107), which was significantly higher than in both DCIS 35.7% (15/42) and adjacent non-tumor tissues 12.3% (8/65). High-level expression of LETM1 was positively correlated with late clinical stage, poor differentiation, lymph node metastasis, disease-free survival (DFS) and 10-year overall survival (OS) rates in TNBC. Further analysis showed that high LETM1 expression along with clinical stage emerged as significant independent risk factors in patients with TNBC. In conclusion, LETM1 protein overexpression is associated with TNBC progression, and may be a potential biomarker for poor prognostic evaluation of TNBC.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Proteínas de Unión al Calcio/biosíntesis , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Proteínas de la Membrana/biosíntesis , Neoplasias de la Mama Triple Negativas/patología , Línea Celular Tumoral , Supervivencia sin Enfermedad , Motivos EF Hand , Femenino , Humanos , Leucina Zippers , Metástasis Linfática , Células MCF-7 , Persona de Mediana Edad , Membranas Mitocondriales/patología , Proteínas Mitocondriales/biosíntesis , Neoplasias de la Mama Triple Negativas/mortalidad
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