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1.
Environ Pollut ; 320: 121034, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36623790

RESUMEN

Sichuan Province is rich in crop straw, yet little is known about its spatial distribution pattern, potential in replacing chemical fertilizer and mitigating nutrient loss. Based on the statistical data and literature review, the spatial distribution and potential of nutrient resources in crop straw for replacing chemical fertilizers was evaluated in this study. The nutrient loss with both crop incorporation and chemical fertilizer application were examined using a nutrient release coefficient method and compared. Results showed that Chengdu Plain, Northeast and South Sichuan produced more than 95% of the total straw nutrient resources during the period of 2016-2020. The potential of crop straw to substitute potassium (K), nitrogen (N) and phosphorus (P) fertilizer were K2O 33.08-285.95 kg hm-2, N 9.52-82.32 kg hm-2 and P2O5 4.91-28.71 kg hm-2, respectively. If chemical fertilizer was substituted by all the available straw nutrient resources, N and P loss can be decreased by 55.12% and 65.84% in average in Sichuan Province. 343.93 t of N loss and 20.05 t of P loss can be reduced in plain areas, 122.88 t of N loss and 46.29 t of P loss can be reduced in mountainous and hilly areas, and 5.65 t of t N loss and 3.54 t of P loss can be reduced in plateau areas. It can be concluded that there were rich crop straw nutrient resources in Sichuan Province with obvious spatial variability, solid consideration should be put on to the proper use of crop straw nutrient resources, with the aim of chemical fertilizer reduction, nutrient loss reduction and sustainable development.


Asunto(s)
Agricultura , Suelo , Agricultura/métodos , Fertilizantes , China , Nitrógeno/análisis , Nutrientes
2.
World J Clin Cases ; 9(28): 8616-8626, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34754876

RESUMEN

BACKGROUND: Primary intramedullary melanocytoma is an exceedingly rare type of primary melanocytic tumor in the central nervous system. Unfortunately, primary intramedullary melanocytoma lacks specificity in clinical symptoms and imaging features and there is currently no standard strategy for diagnosis or treatment. CASE SUMMARY: A 52-year-old male patient suffered from weakness and numbness involving the bilateral lower limbs for 18 mo, and defecation and erectile dysfunction for 6 mo. Furthermore, these symptoms started to worsen for the last 3 mo. Preoperative magnetic resonance imaging (MRI) revealed an intramedullary tumor located at the T9-T10 level. In subsequently surgery, the maximal safe resection extent approached to 98%. The lesion was confirmed to be melanocytoma by pathological examination. In addition, the possibility of original melanocytoma outside the spinal cord was excluded after the examination of the whole body. Therefore, a diagnosis of primary intramedullary melanocytoma was established. The patient refused to accept radiotherapy or Gamma Knife, but MRI examination on July 28, 2020 showed no sign of development. In addition, on April 10, 2021, the recent review showed that the disorder of defecation and lower limbs improved further but erectile dysfunction benefited a little from the surgery. CONCLUSION: After diagnosing intramedullary melanocytoma by postoperative pathology, the inspection of the whole body contributed to excluding the possibility of metastasis from other regions and further suggested a diagnosis of primary intramedullary melanocytoma. Complete resection, adjuvant radiation, and regular review are critical. In addition, maximal safe resection also benefits prognosis while the tumor is difficult to be resected totally.

3.
ACS Appl Mater Interfaces ; 12(45): 50756-50762, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33119275

RESUMEN

Germanium nanomaterials are important for their potential applications in many fields. However, current synthetic technologies usually involve either high-cost explosive reagents or complicated facilities, which make the mass production especially challenging. In this report, a method was developed to synthesize nano-Ge materials conveniently, realized by decomposing LiZnGe in air at room temperature. The process is nontoxic, inexpensive, and, most of all, very suitable for large-scale production in combination with ball milling. The as-prepared Ge nanomaterials are crystalline whose structures can be flexibly tuned through the ball milling syntheses. As the lithium-ion battery anode, such Ge nanomaterials exhibited long-term cycle ability with high specific capacity as well as excellent rate performance. These results not only provided a very efficient way to prepare nano-Ge in lab or even promising industry production but also suggested a universal method in synthesizing the tetrels elemental nanomaterials.

4.
Oncotarget ; 7(42): 68473-68488, 2016 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-28049184

RESUMEN

FGFRs are considered essential targets for cancer therapy. We previously reported that msFGFR2c, a Ser252Trp mutant soluble ectodomain of FGFR2IIIc, inhibited tumor growth by blocking FGF signaling pathway. However, the underlying molecular mechanism is still obscure. In this study, we reported that msFGFR2c but not wild-type soluble ectodomain of FGFR2IIIc (wsFGFR2c) could selectively bind to c subtype of FGFRs in the presence of FGF-2. Thermodynamic analysis demonstrated that msFGFR2c bound to wsFGFR2c in the presence of FGF-2 with a K value of 6.61 × 105 M-1. Molecular dynamics simulations revealed that the mutated residue Trp252 of msFGFR2c preferred a π-π interaction with His254 of wsFGFR2c. Concomitantly, Arg255 of msFGFR2c and Glu250 of wsFGFR2c adjusted their conformations and formed three H-bonds. These two interactions therefore stabilized the final structure of wsFGFR2c and msFGFR2c heterocomplex. In FGFR2IIIc-positive/high FGF-2-secreted BT-549 cells, msFGFR2c significantly inhibited the proliferation and induced apoptosis by the blockage of FGF-2-activated FGFRs phosphorylation, also the growth and angiogenesis of its xenograft tumors implanted in chick embryo chorioallantoic membrane model. While weaker the above inhibitory effects of msFGFR2c were observed on FGFR2IIIc-negative/low FGF-2-secreted MCF-7 and MDA-MB-231 cell lines in vitro and in vivo. Moreover, msFGFR2c significantly inhibited the proliferation of FGFR1IIIc-positive NCI-H1299 lung cancer cells by the suppression of FGF-2-induced FGFR1 activation and suppressed the growth of NCI-H1299 transplanted tumors in nude mice. In sum, msFGFR2c is a potential anti-tumor agent targeting FGFR2c/FGFR1c-positive tumor cells. These findings also provide a molecular basis for msFGFR2c to disrupt the activation of FGF signaling.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/metabolismo , Simulación de Dinámica Molecular , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Proteínas Recombinantes/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Sitios de Unión/genética , Línea Celular Tumoral , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/metabolismo , Factor 2 de Crecimiento de Fibroblastos/química , Factor 2 de Crecimiento de Fibroblastos/farmacología , Células HEK293 , Humanos , Células MCF-7 , Ratones Desnudos , Mutación , Neoplasias/irrigación sanguínea , Neoplasias/genética , Neoplasias/metabolismo , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Unión Proteica/efectos de los fármacos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/química , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología , Trasplante Heterólogo
5.
Reprod Toxicol ; 51: 79-89, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25549948

RESUMEN

n-Hexane is widely used in industry and its metabolite, 2,5-hexanedione (2,5-HD), has been implicated as a neural toxin in the developing fetus. Using the chick embryo model, we have previously revealed the neurotoxicity of 2,5-HD during development and established that high dose of 2,5-HD was embryo lethal. In view of the close linkage in biology for neurogenesis and angiogenesis, we speculated that it was most likely caused by cardiovascular dysplasia, therefore in this study, we investigated the effects of 2,5-HD on the development of the vasculature, which involves vasculogenesis and angiogenesis. Using gastrulating chick embryos as a model, we demonstrated that the hemangioblasts (precursor of hematopoietic and endothelial cells) migrated to the area opaca where they form the blood islands. However, this process was impaired when the embryos were treated with 2,5-HD, suggesting that 2,5-HD is capable of impairing vasculogenesis. To study the effect of 2,5-HD exposure on angiogenesis, we used the chick yolk-sac membrane (YSM) and chorioallantoic membrane (CAM) models. We found that, at low (0.02M) concentration, 2,5-HD stimulated angiogenesis while at higher concentrations (>0.1M) it inhibited this process. This biphasic response of angiogenesis to 2,5-HD exposure was found to be associated with altered expression of the VEGF-R, FGF-2 and angiogenin. Moreover, we also determined that 2,5-HD exposure increased the reactive oxygen species (ROS) production. In conclusion, 2,5-HD could induce dysplasia in the developing vasculature, which in turn could cause extravascular hemolysis and the embryos to die.


Asunto(s)
Hexanonas/toxicidad , Neovascularización Fisiológica/efectos de los fármacos , Neurotoxinas/toxicidad , Animales , Antígenos CD/genética , Cadherinas/genética , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/efectos de los fármacos , Factor 2 de Crecimiento de Fibroblastos/genética , Proteínas Tirosina Quinasas/genética , Especies Reactivas de Oxígeno/metabolismo , Ribonucleasa Pancreática/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 3 de Factores de Crecimiento Endotelial Vascular/genética , Saco Vitelino/irrigación sanguínea , Saco Vitelino/efectos de los fármacos
6.
Exp Cell Res ; 320(2): 354-64, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24162003

RESUMEN

1,1-Dimethyl-4-phenyl piperazine iodide (DMPP) is a synthetic nicotinic acetylcholine receptor (nAChR) agonist that could reduce airway inflammation. In this study, we demonstrated that DMPP could dramatically inhibit glioma size maintained on the chick embryonic chorioallantoic membrane (CAM). We first performed MTT and BrdU incorporation experiments on U87 glioma cells in vitro to understand the mechanism involved. We established that DMPP did not significantly affect U87 cell proliferation and survival. We speculated that DMPP directly caused the tumor to regress by affecting the vasculature in and around the implanted tumor on our chick CAM model. Hence, we conducted detailed analysis of DMPP's inhibitory effects on angiogenesis. Three vasculogenesis and angiogenesis in vivo models were used in the study which included (1) early chick blood islands formation, (2) chick yolk-sac membrane (YSW) and (3) CAM models. The results revealed that DMPP directly suppressed all developmental stages involved in vasculogenesis and angiogenesis - possibly by acting through Ang-1 and HIF-2α signaling. In sum, our results show that DMPP could induce glioma regression grown on CAM by inhibiting vasculogenesis and angiogenesis.


Asunto(s)
Yoduro de Dimetilfenilpiperazina/farmacología , Glioma/irrigación sanguínea , Glioma/patología , Neovascularización Patológica/prevención & control , Animales , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Embrión de Pollo , Humanos , Inducción de Remisión , Carga Tumoral/efectos de los fármacos , Células Tumorales Cultivadas , Saco Vitelino/irrigación sanguínea , Saco Vitelino/efectos de los fármacos
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