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Objective: To investigate the safety and efficacy of piezosurgery in anterior cervical discectomy and fusion (ACDF) for cervical spondylotic myelopathy (CSM). Methods: 47 patients with complex CSM (cCSM) underwent ACDF surgery from 2014 to 2017. Among these patients, 26 underwent ACDF using piezosurgery (group A) and 21 underwent ACDF by using traditional tools such as high-speed air drill, bone curette, and Kerrison bone punch (group B). Average surgical time, intraoperative blood loss, surgical complications, preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, and improvement rate were measured. Results: Average surgical time and intraoperative blood loss were significantly lower in group A than those in group B (P < 0.01). The incidences of surgical complications were 3.8% and 23.8% in the A and B groups (P < 0.05), respectively. There were no significant differences in JOA scores and improvement rates between data collection periods at preoperative, 3-day postoperative, and 1-year postoperative follow-ups (P > 0.05). Conclusion: For treating cCSM, both the piezosurgery and traditional tools led to significant neurological improvement. However, the piezosurgery was superior to the traditional tools in terms of surgical time, blood loss, and complication rate. Hence, piezosurgery was a safe and effective adjunct for ACDF treating cCSM.
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Rural land use patterns in southern China centered on household grain crop production have observed significant changes in the past few decades, profoundly affecting the release and fixation of carbon and nitrogen in the paddy soil of the region. This study selected different land use patterns developed in purple paddy soil on a decadal time scale, examined the changing rate of soil carbon and nitrogen of the purple paddy soil after abandonment, dry-farming, and fish-farming, and revealed the impact of land use changes on the balance of soil carbon and nitrogen. Results showed that the loss rates of soil organic carbon, readily oxidizable organic carbon and total nitrogen at the initial stage of dry-farming were most considerable, followed by abandonment and fish-farming. An average of 11.95-13.94 g kg-1 soil organic carbon loss and 0.90-1.03 g kg-1 total nitrogen loss of the cultivation horizon were observed when purple paddy soil was abandoned and dry farmed. In comparison, the net release of soil organic carbon and total nitrogen after fish-farming were 6.64 and -0.23 g kg-1. The changes of land use of rural area driven by rising labor cost and market demand have been inducing a continuous decline in soil C:N and significantly reducing the purple paddy soil's carbon sequestration ability. The promotion of no-tillage management, increase of organic manure application, and avoidance of over-use of nitrogen fertilizer in dryland farming need to be further considered to meet the dual pressures of China's resource constraints and carbon neutrality goals. A regression model may predict the changes in soil carbon after the change of paddy soil utilization, which provides a pathway for predicting changes in farmland carbon sequestration potential and carbon storage caused by changes in paddy soil utilization in the future.
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Carbono , Suelo , Agricultura , Animales , Carbono/análisis , Secuestro de Carbono , China , Nitrógeno/análisisRESUMEN
The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth and metabolism in response to various environmental inputs, especially amino acids. In fact, the activity of mTORC1 is highly sensitive to changes in amino acid levels. Over past decades, a variety of proteins have been identified as participating in the mTORC1 pathway regulated by amino acids. Classically, the Rag guanosine triphosphatases (GTPases), which reside on the lysosome, transmit amino acid availability to the mTORC1 pathway and recruit mTORC1 to the lysosome upon amino acid sufficiency. Recently, several sensors of leucine, arginine, and S-adenosylmethionine for the amino acid-stimulated mTORC1 pathway have been coming to light. Characterization of these sensors is requisite for understanding how cells adjust amino acid sensing pathways to their different needs. In this review, we summarize recent advances in amino acid sensing mechanisms that regulate mTORC1 activity and highlight these identified sensors that accurately transmit specific amino acid signals to the mTORC1 pathway.
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Aminoácidos/química , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Animales , Arginina/química , Membrana Celular/metabolismo , GTP Fosfohidrolasas/metabolismo , Regulación de la Expresión Génica , Aparato de Golgi/metabolismo , Humanos , Leucina/química , Lisosomas/metabolismo , Metionina/química , S-Adenosilmetionina/química , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
In the title compound, C(9)H(12)NO(2) (+)·ClO(4) (-), an intra-molecular N-Hâ¯O inter-action results in the formation of a six-membered ring having a twisted chair conformation. In the crystal structure, inter-molecular O-Hâ¯O, N-Hâ¯O and C-Hâ¯O inter-actions link the mol-ecules into a network. A weak C-Hâ¯π inter-action is also found.
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A new tetra-dentate chiral Schiff base ligand, C(16)H(26)N(2)O(2), has been synthesized by the reaction of acetyl-acetone with (1R,2R)-(-)-1,2-diamino-cyclo-hexane. Both of the mol-ecules in the asymmetric unit are of the same chirality (R configuration), since the absolute configuration was determined by the starting reagent (1R,2R)-(-)-1,2-diamino-cyclo-hexane. The six-membered cyclo-hexane ring is in a chair conformation, and the substituents are equatorial in the most stable conformation (trans-cyclo-hexyl). At the ring substituents, large conjugated -C=N-CH=C-OH systems exist, resulting from the original ketone converted into the enol form. With H atoms excluded, the atoms of each substituent lie in the same plane. The two mol-ecules in the asymmetric unit have almost the same structure, with slight differences in the torsion angles between the substituents and the cyclo-hexane ring; the corresponding N(1)-(C-C-C)(cyclo-hexa-ne) torsion angles are -177.2â (3) and 179.3â (4)° in one mol-ecule and -176.5â (3) and 178.4â (4)° in the other. Two intra-molecular O-Hâ¯N hydrogen bonds exist in each mol-ecule.
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The title coordination polymer, [Zn(C(8)H(4)N(4)O(2))(H(2)O)](n), was prepared by the hydro-thermal reaction of zinc nitrate and 2-(1H-tetra-zol-5-yl)benzoic acid. Two types of coordinated zinc cations exist in the structure. One is tetra-hedrally coordinated by two O and two N from two ligands, the other is octa-hedrally coordinated by two N and two O from two ligands at equatorial sites and by two O atoms of water mol-ecules at axial sites, resulting in a two-dimensional framework. The crystal structure is stabilized by intra-molecular O-Hâ¯O and O-Hâ¯N hydrogen bonds.
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A new tetra-dentate chiral Schiff base ligand, C(26)H(30)N(2)O(2), has been synthesized by the reaction of 1-phenyl-butane-1,3-dione with (1S,2S)-(-)-1,2-diamino-cyclo-hexane. The chiral centers in the mol-ecule have the same S configuration, since the absolute configuration was determined by that of the starting reagent (1S,2S)-(-)-1,2-diamino-hexane. The cyclo-hexane ring is in a chair conformation, and the substituents are equatorial in the most stable conformation (trans-cyclo-hexyl). The crystal structure is stabilized by two intra-molecular O-Hâ¯N hydrogen bonds and a weak C-Hâ¯π inter-action.
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The title compound, [Cd(2)(C(8)H(4)N(4)O(2))(2)(H(2)O)(2)](n), is a coordination polymer prepared by the hydro-thermal reaction of cadmium(II) chloride and 2-(1H-tetra-zol-5-yl)benzoic acid. Two types of coordinated cadmium cations exist in the structure. One is located on a twofold axis and is coordinated by four O and two N atoms from four symmetry-related ligands, forming a trigonal-prismatic coordination polyhedron. The other is located on an inversion center and is octa-hedrally coordinated by two N and two O atoms from two ligands in equatorial sites, and two water mol-ecules in axial sites. The organic ligand bridges three Cd atoms, through a carboxyl-ate group and two N atoms of the tetra-zolate unit. This mode of coordination results in a two-dimensional framework. The crystal structure is stabilized by inter-molecular O-Hâ¯O and O-Hâ¯N hydrogen bonds.
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The title compound, [CdCl(2)(C(9)H(11)NO(2))](n), is a coordination polymer prepared by the hydro-thermal reaction of cadmium(II) chloride and 3-amino-3-phenyl-propanoic acid. Geometric parameters are in the usual ranges. The cadmium cation is octa-hedrally coordinated by four Cl atoms at equatorial sites and two O atoms from two ligands at the axial sites. The material is composed of one-dimensional extended polymeric chains in which two Cl atoms bridge Cd atoms. The crystal structure is stabilized by an intra-molecular N-Hâ¯O hydrogen bond.
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OBJECTIVE: To study the clinical significance of changes of serum myocardial enzymes in patients with acute carbon monoxide poisoning. METHODS: To determine the dynamic changes of the activity of myocardial enzymes and ECG in 62 patients with acute CO poisoning. RESULTS: In patients with acute CO poisoning 5 kinds of myocardial enzymes begin to increase within 24 hours, the activities of aspartate aminotransferase (AST), creatine phosphokinase (CPK), lactic dehydrogenase (LDH), alpha-hydroxybutyrate dehydrogenase (alpha-HBDH), CPK isoenzyme (CK-MB) were (20.2 +/- 12.3), (151.6 +/- 91.8), (146.8 +/- 50.4), (154.8 +/- 47.7), (13.8 +/- 8.1) U/L respectively, while those in control group were (12.1 +/- 6.7), (90.6 +/- 17.3), (118.7 +/- 13.5), (89.9 +/- 27.9), (5.9 +/- 3.3) U/L respectively. There was significant difference between two groups (P < 0.01); 3 d later, the activities of 5 enzymes were still increased [(21.3 +/- 12.3), (105.8 +/- 51.4), (144.8 +/- 51.4), (159.8 +/- 35.4), (16.2 +/- 9.1) U/L respectively]. 7 and 12 d later, the activities of alpha-HBDH and CK-MB were still higher than those of control (P < 0.01). LDH(1) and LDH(2) increased to peak value in 24 h after poisoning (35.3 +/- 5.8), (43.8 +/- 5.7) U/L vs (24.8 +/- 3.9), (36.9 +/- 4.3) U/L, P < 0.01. The abnormal rate of serum LDH(1) was 78.7%, LDH(2) 58.3%, LDH 45.2%, CK-MB 37.1%, alpha-HBDH 33.6% and the abnormal rate of ECG was less than 10%. CONCLUSION: Acute carbon monoxide poisoning may cause myocardial injury. Determination of serum myocardial enzymes may contribute to showing myocardial injury, early diagnosis and treatment, results of treatment and prognosis.