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1.
J Hazard Mater ; 476: 135076, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38991636

RESUMO

The introduction of anthropogenic inputs into natural systems may lead to enduring alterations in the innate characteristics of Rare Earth Elements (REEs). Against this backdrop, the evolutionary processes and environmental drivers of REEs in soil remain uncertain. A 3000-year soil chronosequence with uniform parent material was established in reclaimed farmland along the Yangtze River, reconstructing, for the first time, the dynamic processes of REE accumulation and fractionation over a long-time scale. Analysis of 122 soil samples showed REE concentrations ranging from 146.00 to 216.56 µg/g. Based on reclamation duration, three significant stages of REE evolution were identified: natural leaching, rapid accumulation, and stable accumulation with differentiation. Reclaimed soil after 3000 years exhibited a 14.1 % increase in REE concentrations compared to fresh sediments, attributed to anthro -pedogenic processes. Moreover, Heavy Rare Earth Elements (HREEs) accumulated faster than Light Rare Earth Elements (LREEs), particularly in deeper soils (60-100 cm), where HREE concentrations rose by 34.3 %, mainly due to acidic environments promoting HREE fixation. Additionally, the potential ecological risk posed by REEs heightened with reclamation duration, with HREEs exhibiting a sensitivity of 83 % to 94 %. Our findings stress the urgency of carefully monitoring exogenous REEs introduced through anthropogenic activities, particularly HREEs.

2.
Curr Med Imaging ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38415457

RESUMO

AIM: To identify age-matched healthy volunteers, non-cirrhotic chronic liver disease (CLD) and cirrhotic patients based on portal hemodynamic parameters using 4D flow MRI. METHODS: A total of 10 age-matched healthy volunteers and 69 CLD patients were enrolled and underwent 4D flow MRI prospectively. 4D flow MR images were processed by an MD in biomedical engineering working on the GTFlow platform. Portal hemodynamic parameters include net flow (mL/cycle), flow volume per second through the lumen (mL/sec), average flow velocity (cm/sec), and maximum flow velocity (cm/sec). The difference in portal hemodynamic parameters of 4D flow MRI was compared among healthy volunteers, non-cirrhotic CLD patients and patients with cirrhosis by one-way ANOVA or Kruskal-Wallis nonparametric test and post hoc tests. RESULTS: 10 CLD patients without cirrhosis and 56 patients with cirrhosis were eventually included, along with 10 healthy volunteers who were divided into three groups. 3 patients with cirrhosis whose image quality did not meet the requirements were excluded. There were no significant differences in portal hemodynamic parameters among the three groups except portal average velocity (P > 0.05). There was no statistical difference in all portal hemodynamic parameters of 4D flow MRI between healthy volunteers and patients with cirrhosis (P > 0.05). There were significant differences in portal average velocity between non-cirrhotic CLD patients, healthy volunteers and patients with cirrhosis, respectively (11.44±3.93 vs 8.10±2.66, P=0.013; 11.44±3.93 vs 8.60±2.22, P=0.007). CONCLUSION: Portal average velocity obtained by 4D flow MRI can be an auxiliary means to identify cirrhosis in patients with CLD.

3.
Huan Jing Ke Xue ; 45(1): 314-322, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216481

RESUMO

The allocation dynamics of soil carbon pools during soil development and land use are the key to revealing the carbon cycle process. To clarify the distribution of the soil carbon pool and its change trend, a soil reclamation chronosequence (0 a, 60 a, 160 a, 280 a, 1 000 a, and 1 500 a reclamation) was established in a typical alluvial plain in the Lower Yangtze River, and the content and density of soil organic carbon (SOC), soil inorganic carbon (SIC), particulate organic carbon (POC), and mineral-associated organic carbon (MAOC), along with carbon sequestration potential (CSP) indicators of topsoil under different land use types were measured and analyzed. The results showed that after approximately 1 500 a reclamation, the SOC content developed from the Yangtze River alluvial deposits generally increased by 4.9% after the initial decline, whereas the SIC content decreased to 0.2% from 25.8% of the total carbon content due to its rapid leaching. The MAOC content was normally higher than that of POC, and MAOC was contributing 48.0%-79.7% of the SOC accumulation. In this region, the soil organic carbon density (SOCD) accounted for 57.4%-100% of the total carbon density, the soil carbon sequestration levels (CSL) ranged from 18.6% to 56.1%, and CSP under paddy-dryland rotation increased by 20.8% compared to that under dryland. The C/N ratio and total nitrogen content are key factors in explaining soil carbon accumulation processes, and the reclamation year plays an important role in evaluating soil carbon sequestration levels. After long-term utilization, the cultivated soil in the Yangtze River floodplain must be carefully managed through balanced fertilization to maintain soil productivity, promote the accumulation of SOC, and avoid the decline in soil carbon sequestration capacity.

4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(2): 162-167, 2023 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-36796810

RESUMO

Objective: To explore the risk factors for osteonecrosis of the femoral head (ONFH) after treatment of femoral neck fractures with femoral neck system (FNS). Methods: Between January 2020 and February 2021, 179 patients (182 hips) with femoral neck fractures treated by FNS fixation were selected for retrospective analysis. There were 96 males and 83 females with an average age of 53.7 years (range, 20-59 years). There were 106 cases of low-energy-induced injury and 73 cases of high-energy-induced injury. The fractures were classified as type Ⅱ in 40 hips, type Ⅲ in 78 hips, and type Ⅳ in 64 hips according to Garden classification standard, and as typeⅠin 23 hips, type Ⅱ in 66 hips, and type Ⅲ in 93 hips according to Pauwels classification standard. There were 21 patients with diabetes. Patients were divided into ONFH group and non-ONFH group according to whether ONFH occurred at last follow-up. The data of the patients were collected, including age, gender, body mass index (BMI), trauma mechanism, bone mineral density, having diabetes or not, Garden classification and Pauwels classification of fractures, fracture reduction quality, femoral head retroversion angle, and removal of internal fixator or not. The above factors were analyzed by univariate analysis, and then multivariate logistic regression analysis was used to identify risk factors. Results: Total 179 patients (182 hips) were followed up 20-34 months (mean, 26.5 months). Of these, 30 cases (30 hips) developed ONFH at 9-30 months after operation (ONFH group), and the incidence of ONFH was 16.48%. And 149 cases (152 hips) had no ONFH at last follow-up (non-ONFH group). The univariate analysis showed that there were significant differences between groups in bone mineral density, having diabetes or not, Garden classification, femoral head retroversion angle, and fracture reduction quality ( P<0.05). The multivariate logistic regression analysis showed that the Garden type Ⅳ fracture, reduction quality of grading Ⅲ, femoral head retroversion angle >15°, complicated with diabetes were the risk factors for ONFH after FNS fixation ( P<0.05). Conclusion: For the patients with Garden type Ⅳ fracture, poor quality of fracture reduction, femoral head retroversion angle >15°, and diabetes, the risk of ONFH after FNS fixation increases.


Assuntos
Fraturas do Colo Femoral , Necrose da Cabeça do Fêmur , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Colo do Fêmur/cirurgia , Cabeça do Fêmur/cirurgia , Estudos Retrospectivos , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fraturas do Colo Femoral/cirurgia , Fatores de Risco , Resultado do Tratamento
5.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(11): 1434-1439, 2022 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-36382464

RESUMO

Objective: To summarize the research progress of femoral neck system (FNS) in the treatment of femoral neck fracture in young and middle-aged patients. Methods: The literature on FNS at home and abroad in recent years was extensively reviewed, and the results of mechanical and clinical studies on FNS were summarized based on clinical experience. Results: FNS has good mechanical stability, which can reduce complications such as femoral neck shortening, internal fixation failure, and varus caused by mechanical instability. At present, FNS is mainly selected for comparison with cannulated compression screws and dynamic hip screws in clinical research. The results show that FNS has the advantages of minimally invasive, short operation time, less intraoperative fluoroscopy, earlier postoperative weight-bearing and fracture healing, and better hip function recovery. Conclusion: As a new internal fixator, FNS has achieved satisfactory results in the current research. FNS has good mechanical advantages, which is beneficial to fracture healing and the recovery of hip joint function after operation. However, whether FNS can reduce the incidence of nonunion and osteonecrosis of the femoral head remains to be further clarified.


Assuntos
Fraturas do Colo Femoral , Pessoa de Meia-Idade , Humanos , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur/cirurgia , Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Consolidação da Fratura , Estudos Retrospectivos , Resultado do Tratamento
6.
Pain Physician ; 25(6): E805-E813, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36122263

RESUMO

BACKGROUND: Percutaneous kyphoplasty (PKP) is an effective treatment for osteoporotic vertebral compression fractures (OVCF). Comparisons of different approaches have previously focused primarily on x-rays. Three-dimensional (3D) computed tomography (CT) enables better imaging evaluation of bone cement distribution. OBJECTIVES: To compare the CT imaging parameters and clinical efficacies of unilateral and bilateral PKP. STUDY DESIGN: This was a prospective, nonrandomized controlled study. SETTING: Department of Orthopedics from an affiliated hospital. METHODS: Seventy-two single-level OVCF patients who underwent 3D CT between 2018 and 2020 were evaluated prospectively. All patients underwent PKP and were assigned to 2 groups: unilateral PKP and bilateral PKP. Imaging outcomes were assessed by determining the cement volume, leakage, dispersion index, vertebral height (VH) and the cement volume of the noninjected and injected sides. Clinical outcomes were evaluated using the Visual Analog Scale (VAS). The correlations between the bone cement volume or dispersion index and the VAS, VH improvement rate (VHIR), or bone cement leakage were also evaluated. RESULTS: The mean follow-up time was 17.1 months. The postoperative VH and VAS in both groups were significantly improved (P < 0.05). However, there were no statistically significant differences in the cement volume, leakage or dispersion index, VH, or VAS between the 2 groups. No statistically significant differences in the cement volume or VH were found between the noninjected and injected sides within the unilateral group. The operative time was significantly shorter in the patients who underwent unilateral PKP. Unilateral PKP in which the bone cement did not cross the midline had a higher VAS compared with bilateral PKP. Both the bone cement volume and dispersion index displayed a positive correlation with the VHIR, but no correlation with the VAS or bone cement leakage. LIMITATIONS: This study was limited by the nonrandomized design, small sample size, and short follow-up period. CONCLUSIONS: While unilateral PKP was as effective as bilateral PKP, it had a shorter operation time. However, the bilateral PKP approach might be followed when bone cement is distributed in only one side following the unilateral PKP procedure.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Cimentos Ósseos/uso terapêutico , Fraturas por Compressão/cirurgia , Humanos , Cifoplastia/métodos , Estudos Prospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia , Tomografia Computadorizada por Raios X
7.
Fitoterapia ; 127: 362-366, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29626624

RESUMO

Chemical investigation on the solid rice culture of Trichoderma atroviride S361, an endophyte isolated from Cephalotaxus fortunei, has afforded a pair of novel N-furanone amide enantiomers, (-)-trichodermadione A (1a) and (+)-trichodermadione A (1b), and a new cyclohexenone sesquiterpenoid, trichodermadione B (2), together with six known secondary metabolites. Chiral separation of compound 1 was successfully performed on a Lux Cellulose-2 column. Their structures were elucidated by detailed spectroscopic analyses on the basis of NMR, HRMS, and ECD data, and the absolute configurations of the new compounds were determined by computational analyses of their electronic circular dichroism (ECD) spectra and Snatzke's method. Compounds 1a, 1b and 2 were also evaluated for their cytotoxicity against DU145 and PC3 cell lines, as well as inhibitory effects against the production of NO in LPS-stimulated RAW264.7 cells.


Assuntos
Cephalotaxus/microbiologia , Trichoderma/química , Animais , Linhagem Celular Tumoral , Endófitos/química , Humanos , Camundongos , Estrutura Molecular , Células RAW 264.7
8.
Front Microbiol ; 8: 2694, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29403449

RESUMO

Salvia miltiorrhiza is known for tanshinones and salvianolic acids, which have been shown to have a protective effect against ROS, especially for cardiovascular diseases and other various ailments of human organs. Due to the low yield of tanshinones and their analogs in S. miltiorrhiza, multiple stimulation strategies have been developed to improve tanshinones production in plant tissue cultures. Endophytic fungi have been reported to form different relationships with their host plants, including symbiotic, mutualistic, commensalistic, and parasitic interactions. Thus we take the assumption that endophytic fungi may be a potential microbial tool for secondary metabolism promotion in medicinal plants. We recently isolated Chaetomium globosum D38 from the roots of S. miltiorrhiza and our study aimed to examine the effects of this live endophytic fungus D38 and its elicitor on the accumulation of tanshinones in the hairy root cultures of S. miltiorrhiza. Our results revealed that C. globosum D38 mainly colonized in the intercellular gap of xylem parenchyma cells of S. miltiorrhiza hairy roots during the long term co-existence without any toxicity. Moreover, both of the live fungus and its mycelia extract could increase the production of tanshinones, especially for dihydrotanshinone I and cryptotanshinone. The effect of the mycelia extract was much stronger than that of the live fungus on tanshinones synthesis, which significantly increased the transcriptional activity of those key genes in tanshinone biosynthetic pathway. Furthermore, the live C. globosum D38 could also be made into biotic fertilizer used for S. miltiorrhiza seedlings culture, which not only significantly promoted the growth of the host plant, but also notably enhanced the accumulation of tanshinones and salvianolic acids. We thus speculated that, in the soil environment D38 could form bitrophic and mutual beneficial interactions with the host and enhance the plant growth and its secondary metabolism on the whole so as to have facilitative effects on both tanshinones and salvianolic acids accumulation. In conclusion, Chaetomium globosum D38 was a highly beneficial endophytic fungus for the growth and metabolism of S. miltiorrhiza.

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