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1.
World J Clin Cases ; 12(17): 3123-3129, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38898829

RESUMO

BACKGROUND: Due to mechanical imbalance in the spine, elderly scoliosis patients tend to develop vertebral fracture nonunion, i.e., Kümmell disease, when osteoporotic vertebral compression fractures occur. However, accompanying vertebral rotational deformities make surgical procedures challenging risky. Such patients are usually compelled to undergo conservative treatment and there are very few reports on minimally invasive surgeries for them. We first-time report a patient with Kümmell disease and lumbar scoliosis treated with percutaneous kyphoplasty (PKP) under O-arm guidance. CASE SUMMARY: An 89-year-old female was admitted to the hospital due to delayed low back pain after a fall. She was diagnosed with Kümmell disease based on physical and radiologic examinations. The patient experienced severe scoliosis and subsequently underwent O-arm-guided kyphoplasty, resulting in a significant alleviation of low back pain. CONCLUSION: PKP has good efficacy in treating Kümmell disease. However, surgical risks are elevated in scoliosis patients with Kümmell disease due to the abnormal anatomical structure of the spine. O-arm assisted operations play a crucial role in decreasing surgical risks.

2.
Sci Rep ; 13(1): 3969, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894575

RESUMO

This paper proposes a normal oriented impact stiffness of a three-supporting cable flexible barrier under a small pretension stress to estimate the structural load behaviour, and employs two categories of small-scale debris flows (coarse and fine) to explore the stiffness evolution through physical model experiments with high-speed photography and load sensing. Results suggest that the particle-structure contact is essential to the normal load effect. Coarse debris flow performs more frequent particle-structure contact and exerts evident momentum flux, while fine debris flows with few physical collisions impart much smaller one. The middle-sited cable that receives only tensile force from vertical equivalent cable-net joint system exhibits indirect load behaviour. The bottom-sited cable shows high load feedback due to the sum of direct contact of debris flow and tensile forces. The relationship between impact loads and maximum cable deflections can be explained by power functions according to quasi-static theory. The impact stiffness is not just affected by the particle-structure contact but by the flow inertia and particle collision effect. Savage number Nsav and Bagnold number Nbag manage to depict the dynamical effects on the normal stiffness Di. Experiments indicate that Nsav has positive linear correlation with the nondimensionalization of Di, whilst Nbag has positive power correlation with the nondimensionalization of Di. This idea is an alternative scope for the study on flow-structure interaction and may contribute to the parameter identification in numerical simulation of the debris flow-structure interaction and the optimization of the design standardization.

3.
Curr Genomics ; 24(6): 368-384, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38327651

RESUMO

Introduction: Hepatocellular carcinoma (HCC) has a high mortality rate, with curative resection being the primary treatment. However, HCC patients have a large possibility of recurrence within 5 years after curative resection. Methods: Thus, identifying biomarkers to predict recurrence is crucial. In our study, we analyzed data from CCLE, GEO, and TCGA, identifying eight oncogenes associated with HCC. Subsequently, the expression of 8 genes was tested in 5 cases of tumor tissues and the adjacent non-tumor tissues. Then ATP6AP1, PSMD14 and HSP90AB1 were selected to verify the expression in 63 cases of tumor tissues and the adjacent non-tumor tissues. The results showed that ATP6AP1, PSMD14, HSP90AB1 were generally highly expressed in tumor tissues. A five-year follow-up of the 63 clinical cases, combined with Kaplan-Meier Plotter's relapse-free survival (RFS) analysis, found a significant correlation between PSMD14 expression and recurrence in HCC patients. Subsequently, we analyzed the PSMD14 mutations and found that the PSMD14 gene mutations can lead to a shorter disease-free survival time for HCC patients. Results: The results of enrichment analysis indicated that the differentially expressed genes related to PSMD14 are mainly enriched in the signal release pathway. Conclusion: In conclusion, our research showed that PSMD14 might be related to recurrence in HCC patients, and the expression of PSMD14 in tumor tissue might be a potential prognostic biomarker after tumor resection in HCC patients.

4.
J Fluoresc ; 31(2): 385-392, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33403518

RESUMO

A new three-dimensional lanthanide metal-organic framework (Ln-MOF), [Eu4(L)4(H2O)8]·10H2O (1, H3L = biphenyl-3'-nitro-3,4',5-tricarboxylic acid), has been constructed via solvothermal technology and its framework has been detected by the single-crystal X-ray diffraction and elemental analyses. Complex 1 with typical emission of Eu3+ ion represents dramatic luminescence quenching affect for picric acid (PA) and the linear Stern-Volmer plot was surveyed in the consistence, ranging from 0.05 to 0.15 mM (Ksv = 98,074 M- 1). Its therapeutic effect of the compound on the cerebral edema caused by cerebral hemorrhage was estimated and the mechanism was explored. Possible binding interactions have been investigated by molecular docking simulations, from which the binding interactions are identified and the carboxyl oxygens are responsible for those identified interactions.


Assuntos
Edema Encefálico/diagnóstico , Hemorragia Cerebral/diagnóstico , Complexos de Coordenação/química , Európio/química , Estruturas Metalorgânicas/química , Picratos/análise , Animais , Edema Encefálico/metabolismo , Hemorragia Cerebral/metabolismo , Complexos de Coordenação/síntese química , Ensaio de Imunoadsorção Enzimática , Estruturas Metalorgânicas/síntese química , Modelos Moleculares , Oxirredução , Protrombina/metabolismo , Ratos , Ratos Sprague-Dawley
5.
Environ Sci Technol ; 54(21): 13598-13609, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33079537

RESUMO

Analysis of stable metal isotopes can provide important information on biogeochemical processes in the soil-plant system. Here, we conducted a repeated phytoextraction experiment using the cadmium (Cd) hyperaccumulator Sedum plumbizincicola X. H. Guo et S. B. Zhou ex L. H. Wu (Crassulaceae) in four different Cd-contaminated agricultural soils over five consecutive crops. Isotope composition of Cd was determined in the four soils before and after the fifth crop, in the plant shoots harvested in all soils in the first crop, and in the NH4OAc extracts of two contrasting soils with large differences in soil pH (5.73 and 7.32) and clay content (20.4 and 31.3%) before and after repeated phytoextraction. Before phytoextraction NH4OAc-extractable Cd showed a slight but significant negative isotope fractionation or no fractionation compared with total Cd (Δ114/110Cdextract-soil = -0.15 ± 0.05 (mean ± standard error) and 0.01 ± 0.01‰), and the extent of fractionation varied with soil pH and clay content. S. plumbizincicola preferentially took up heavy Cd from soils (Δ114/110Cdshoot-soil = 0.02-0.14‰), and heavy isotopes were significantly depleted in two soils after repeated phytoextraction (Δ114/110Cdsoil:P5-soil:P0 = -0.15 ± 0.02 and -0.12 ± 0.01‰). This provides evidence for the existence of specific Cd transporters in S. plumbizincicola, leading to positive isotope fractionation during uptake. After phytoextraction by five sequential crops, the NH4OAc-extractable Cd pool was significantly enriched in heavy isotopes (Δ114/110Cdextract:P5-extract:P0 = 0.07 ± 0.02 and 0.18 ± 0.05‰) despite the preferential uptake of heavy isotopes, indicating the occurrence of root-induced Cd mobilization in soils, which is supposed to favor heavy Cd in the organo-complexes with root exudates. Our results demonstrate that Cd is taken up by S. plumbizincicola via specific transporters, partly after active mobilization from the more strongly bound soil pool such as iron/manganese (hydr)oxide-bound Cd during repeated phytoextraction. This renders S. plumbizincicola a suitable plant for large-scale field phytoremediation.


Assuntos
Sedum , Poluentes do Solo , Biodegradação Ambiental , Cádmio/análise , Isótopos , Solo , Poluentes do Solo/análise
6.
Sci Rep ; 9(1): 16762, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31728043

RESUMO

The 2008 Wenchuan earthquake caused significant economic losses and degradation of regional ecosystems, including the terrestrial vegetation. Since the vegetation root system can enhance the soil's anti-erosion capacity and therefore mitigate the occurrence of slope instabilities, it is beneficial to study the spatial and temporal evolution of vegetation for a long-term assessment of co-seismic secondary disasters. The Mianyuan River Basin, an uninhabited area passing through an active fault located in the earthquake-affected region, was selected as the study area. The Normal Difference Vegetation Index (NDVI) was calculated using remote sensing images from 1994 to 2017 to analyze the process of vegetation growth, loss, fluctuation and recovery. Statistical results suggest that the area in the middle and lower reaches, near the river network, and with a slope of 30 to 40 degrees were variable regions, showing more significant vegetation destruction during the earthquake and faster repair after the seismic event. Besides, vegetation near the fault was damaged more severely after the earthquake, but the active fault did not play an essential role in the vegetation recovery period. In the Mianyuan River Basin, vegetation experienced a volatility period (5 plus or minus one year) before entering the recovery period. In 8 to 9 years after the earthquake, the surficial vegetation could recover to the state before the earthquake.

7.
Sci Rep ; 7(1): 4841, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28687793

RESUMO

A flexible riverbed protection called tetrahedron framed permeable weirs (TFPW) is proposed to protect riverbeds in mountainous areas from scouring. Under clear water conditions, a series of laboratory flume experiments were performed to study the effects of TFPW with different layout types on the stability of riverbeds. The objectives of this paper were to advance understanding of the role that TFPW play in the erosion process of river beds and to optimize the TFPW design for reducing velocity, promoting sediment deposition and good structural stability. Data on velocity distribution and variation, equilibrium bathymetry, flow resistance, bed form characteristics and structural stability were collected and analyzed. The results indicate that (1) with good structural stability, all the TFPW with different layout types had significant effects on the stabilization of the riverbed by reducing velocity, raising the water level, increasing the roughness coefficient, protecting the riverbed from degradation and promoting deposition; and (2) the random Double TFPW with large rates of deceleration, large deposition ranges, and good structural stability, and the paved Single TFPW with small rates of deceleration but large deposition ranges and perfect structural stability, were suitable and optimal for riverbed protection in a clear water channel.

8.
Huan Jing Ke Xue ; 38(9): 3689-3695, 2017 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965248

RESUMO

In order to evaluate the hydrological performance of permeable pavements in mitigating the surface runoff, four pilot-scale permeable pavement units were constructed in Shanghai and compared with impervious pavements. Three of the permeable facilities with waterproof liners included a pervious concrete pavement (facility Ⅰ), permeable interlocking concrete pavement using cement stabilized macadam as the base course (facility Ⅱ) and permeable interlocking concrete pavement using macadam as the base course (facility Ⅲ). The other two facilities were a conventional permeable interlocking concrete pavement without a liner (facility Ⅳ) and an impervious concrete pavement control (facility 0). V-notch flow meters, data loggers, and a rainfall meter were mounted to monitor the hydrological data. A double-ring infiltrometer was applied to evaluate the infiltration rate of the pavements. During the one-year experiment, the surface runoff and the underdrain discharge flow rate of the four pilot-scale facilities were continuously monitored in actual rainfall and the total volume reduction, peak flow reduction, and peak concentrating time of different facilities were investigated. The results showed that the surface steady infiltration rates of permeable interlocking concrete pavements were less than those of the pervious concrete, and the surface steady infiltration rates of the two types of surface layers decreased after one year of usage. The surface runoff reduction of the four facilities showed no significant differences. The water volume reduction rate of the three types of facilities was weak. The annual total volume reduction rates were 24.2%, 28.5%, and 28.4%, and the controlled rainfall amounts were 5.2 mm, 7.8 mm, and 7.8 mm. The peak flow reduction rate and the time to the peak flow of facility Ⅰ were smaller than those of facility Ⅱ and facility Ⅲ. The peak flow reduction rate and the time to the peak flow of the three facilities showed significant negative correlation with rainfall intensity.

9.
Springerplus ; 5(1): 1621, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652194

RESUMO

Substrate entrainment can greatly influence the mass movement process of a debris avalanche because it can enlarge the landslide volume and change the motion characteristics of the sliding masses. To study the interaction between debris avalanches and erodible substrate, physical modeling experiments varying in the mass of granular flow and substrate thickness were performed. The experimental results show that both the entrained materials and the maximum erosion depth are increased with increasing mass of the debris avalanche and decreasing substrate thickness. During the experiment, several tests were recorded using a high-speed digital camera with a frequency of 500 frames per second, so that the process of entrainment could be clearly observed. Combined with the experiment result and results of previous studies from predecessors, the entrainment mechanism during debris avalanches are analyzed and discussed. The entrainment effect of the sliding masses on the loose bed materials include basal abrasion and impact erosion of the avalanche front, the latter of which can contribute to the former by failing or yielding the erodible bed.

10.
Springerplus ; 5(1): 700, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27347472

RESUMO

INTRODUCTION: Estimating groundwater inflow into a tunnel before and during the excavation process is an important task to ensure the safety and schedule during the underground construction process. CASE DESCRIPTION: Here we report a case of the forecasting and prevention of water inrush at the Jinping II Hydropower Station diversion tunnel groups during the excavation process. The diversion tunnel groups are located in mountains and valleys, and with high water pressure head. Three forecasting methods are used to predict the total water inflow of the #2 diversion tunnel. Furthermore, based on the accurate estimation of the water inrush around the tunnel working area, a theoretical method is presented to forecast the water inflow at the working area during the excavation process. DISCUSSION AND EVALUATION: The simulated results show that the total water flow is 1586.9, 1309.4 and 2070.2 m(3)/h using the Qshima method, Kostyakov method and Ochiai method, respectively. The Qshima method is the best one because it most closely matches the monitoring result. According to the huge water inflow into the #2 diversion tunnel, reasonable drainage measures are arranged to prevent the potential disaster of water inrush. The groundwater pressure head can be determined using the water flow velocity from the advancing holes; then, the groundwater pressure head can be used to predict the possible water inflow. The simulated results show that the groundwater pressure head and water inflow re stable and relatively small around the region of the intact rock mass, but there is a sudden change around the fault region with a large water inflow and groundwater pressure head. Different countermeasures are adopted to prevent water inrush disasters during the tunnel excavation process. CONCLUSION: Reasonable forecasting the characteristic parameters of water inrush is very useful for the formation of prevention and mitigation schemes during the tunnel excavation process.

11.
ScientificWorldJournal ; 2013: 540636, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24082854

RESUMO

Two important features of the high slopes at Gushui Hydropower Station are layered accumulations (rock-soil aggregate) and multilevel toppling failures of plate rock masses; the Gendakan slope is selected for case study in this paper. Geological processes of the layered accumulation of rock and soil particles are carried out by the movement of water flow; the main reasons for the toppling failure of plate rock masses are the increasing weight of the upper rock-soil aggregate and mountain erosion by river water. Indoor triaxial compression test results show that, the cohesion and friction angle of the rock-soil aggregate decreased with the increasing water content; the cohesion and the friction angle for natural rock-soil aggregate are 57.7 kPa and 31.3° and 26.1 kPa and 29.1° for saturated rock-soil aggregate, respectively. The deformation and failure mechanism of the rock-soil aggregate slope is a progressive process, and local landslides will occur step by step. Three-dimensional limit equilibrium analysis results show that the minimum safety factor of Gendakan slope is 0.953 when the rock-soil aggregate is saturated, and small scale of landslide will happen at the lower slope.


Assuntos
Conservação dos Recursos Naturais/métodos , Solo , China , Ecossistema
12.
ScientificWorldJournal ; 2013: 272363, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23844387

RESUMO

Dam breaks of landslide dams are always accompanied by large numbers of casualties, a large loss of property, and negative influences on the downstream ecology and environment. This study uses the Jiadanwan landslide dam, created by the Wenchuan earthquake, as a case study example. Several laboratory experiments are carried out to analyse the dam-break mechanism of the landslide dam. The different factors that impact the dam-break process include upstream flow, the boulder effect, dam size, and channel discharge. The development of the discharge channel and the failure of the landslide dam are monitored by digital video and still cameras. Experimental results show that the upstream inflow and the dam size are the main factors that impact the dam-break process. An excavated discharge channel, especially a trapezoidal discharge channel, has a positive effect on reducing peak flow. The depth of the discharge channel also has a significant impact on the dam-break process. The experimental results are significant for landslide dam management and flood disaster prevention and mitigation.


Assuntos
Materiais de Construção , Terremotos , Deslizamentos de Terra , Modelos Teóricos , Reologia/métodos , Rios , Abastecimento de Água , China , Simulação por Computador
13.
Acta Diabetol ; 47(3): 231-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19760291

RESUMO

The aim of this study is to assess the validity of combined use of fasting plasma glucose (FPG) and glycated hemoglobin A1c (HbA1c) as screening tests for diabetes and impaired glucose tolerance (IGT) in high-risk subjects. A total of 2,298 subjects were included. All subjects underwent a 75-g oral glucose tolerance test (OGTT) and HbA1c measurement. Receiver operating characteristic curve (ROC curve) analysis was used to examine the sensitivity and specificity of FPG and HbA1c for detecting diabetes and IGT, which was defined according to the 1999 World Health Organization (WHO) criteria. (1) Based on the ROC curve, the optimal cut point of FPG related to diabetes diagnosed by OGTT was 6.1 mmol/l that was associated with a sensitivity and specificity of 81.5 and 81.0%, respectively; The optimal cut point of HbA1c related to diabetes diagnosed by OGTT was 6.1%, which was associated with a sensitivity and specificity of 81.0 and 81.0%, respectively; The screening model using FPG > or = 6.1 mmol/l or HbA1c > or = 6.1% had sensitivity of 96.5% for detecting undiagnosed diabetes; the screening model using FPG > or = 6.1 mmol/l and HbA1c > or = 6.1% had specificity of 96.3% for detecting undiagnosed diabetes. (2) Based on the ROC curve, the optimal cut point of FPG related to IGT diagnosed by OGTT was 5.6 mmol/l that was associated with a sensitivity and specificity of 64.1 and 65.4%, respectively; The optimal cut point of HbA1c related to IGT diagnosed by OGTT was 5.6%, which was associated with a sensitivity and specificity of 66.2 and 51.0%, respectively; The screening model using FPG > or = 5.6 mmol/l or HbA1c > or = 5.6% had sensitivity of 87.9% for detecting undiagnosed IGT; The screening model using FPG > or = 5.6 mmol/l and HbA1c > or = 5.6% had specificity of 82.4% for detecting undiagnosed IGT. Compared with FPG or HbA1c alone, the simultaneous measurement of FPG and HbA1c (FPG and/or HbA1C) might be a more sensitive and specific screening tool for identifying high-risk individuals with diabetes and IGT at an early stage.


Assuntos
Glicemia/análise , Diabetes Mellitus/diagnóstico , Intolerância à Glucose/diagnóstico , Hemoglobinas Glicadas/análise , Programas de Rastreamento/métodos , Adulto , Idoso , Povo Asiático , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Técnicas de Diagnóstico Endócrino , Jejum/sangue , Feminino , Intolerância à Glucose/sangue , Intolerância à Glucose/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade
14.
Zhonghua Fu Chan Ke Za Zhi ; 44(11): 809-11, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20079029

RESUMO

OBJECTIVE: To investigate the expression and clinical significance of platelet-derived growth factor A (PDGF-A) on placenta tissue from pre-eclampsia. METHODS: The expression of PDGF-A in the placenta of 38 pre-eclampsia patients and 22 normal pregnant women at third trimester was detected by immunohistochemistry method. RESULTS: (1) PDGF-A was mainly expressed in the cytomembrane and cytoplasm of cytotrophoblasts and the endothelial cell of capillary in placenta. (2) The rates of PDGF-A expression of cytotrophoblasts were 63% (24/38) in pre-eclampsia group and 32% (7/22) in normal pregnancy group, which exhibited significant difference (P < 0.05). (3) The rates of PDGF-A expression of endothelial cell were 68% (26/38) in pre-eclampsia group and 27% (6/22) in normal pregnancy group, which also showed significant difference (P < 0.01). (4) The rates of PDGF-A expression of cytotrophoblasts were 39% (7/18) in mild pre-eclampsia patients and 85% (17/20) in severe pre-eclampsia, which reached statistical difference (P < 0.01). CONCLUSION: The increasing expression of PDGF-A in cytotrophoblast and endothelial cell in placenta might confer the occurrence and progression of pre-eclampsia.


Assuntos
Placenta , Pré-Eclâmpsia , Feminino , Humanos , Imuno-Histoquímica , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Terceiro Trimestre da Gravidez , Trofoblastos/metabolismo
15.
Chin Med J (Engl) ; 117(2): 280-5, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14975217

RESUMO

BACKGROUND: There have been no detailed reports of the three-dimensional structure and the relationship between the external and internal vascularizations observed successively for a long duration in the rat fetus, although many authors have studied the vascular morphology of the developing brain. This study examined the three-dimensional structure of both the external and internal vascularizations of the prenatal rat telencephalon from embryonic days 12 (E12) to 20 (E20). METHOD: A microvascular casting method for scanning electron microscopy (SEM) was used in this study, along with vascular staining using gold-gelatin solution-autometallography (GGS-AMG) after intravascular injection of colloidal gold, as well as hematoxylin-eosin (HE) staining for paraffin embedded specimens. RESULTS: In GGS-AMG stains, E16 fetuses had a few short perforating cortical blood vessels (SPCVs); E17 fetuses had long perforating cortico-medullary vessels (LPCVs). Older fetuses had specific patterns of vascular networks in the cortex and the deeper subcortical part of the telencephalon. In the cortex, fine longitudinal blood vessels were connected by transverse channels. The deep telencephalon had fine blood vessels running in all directions. Using SEM, the external vascularization was already visible in E12 fetuses as arborizations of arterial branches, forming a mesh of fine vascular networks covering the telencephalon. A coralliform fine venous plexus was observed in the external vascularization of E16 fetuses. There were ring-like anastomoses and bud-like protrusions in the network of small blood vessels, most likely the angiogenesis of fetal vessels. From E12 to E16, an immature and incomplete internal vascularization began to appear. There were short blood vessels with ballooned terminals branching from the external vascularization. They penetrated the brain tissue to form networks in the superficial layer, comparable to SPCVs. In E17 to E20 fetuses, tortuous venous branches, straight arterial blood vessels, and a fine network of small blood vessels formed the external vascularization. There were fewer arterial than venous branches connecting to the fine networks of small blood vessels. LPCVs were noted at E17, at the time the white matter emerged. They branched from the external vascularization, and perpendicularly penetrated the brain surface, traversing the cortical plate, and entering into the deep brain. At E17, arterial and venous blood vessels could be clearly distinguished in the external vascularization. At E20, the cortex and white matter contained specific arrangements of networks of fine blood vessels, as seen by GGS-AMG staining. CONCLUSION: These findings show that the development of both the external and internal vascularization follows the development of the telencephalon. In particular, the emergence of the cortical plate and white matter on E16 and E17 influence the development of both the internal and the external vascularization. The laminal arrangement of blood vessels was not observed corresponding to the respective laminal neuronal layers.


Assuntos
Vasos Sanguíneos/embriologia , Telencéfalo/irrigação sanguínea , Animais , Vasos Sanguíneos/ultraestrutura , Embrião de Mamíferos , Feto , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar
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