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1.
J Orthop Sci ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39244404

RESUMO

OBJECTIVE: To observe the effect of early cervical functional exercise (CFE) on clinical outcomes and safety of patients after anterior cervical discectomy and fusion (ACDF). METHODS: Sixty patients who underwent ACDF from September 2019 to September 2020 were analyzed and randomly divided into two groups: the CFE group (27 cases) and the usual care (UC) group (33 cases). Then, all patients in the two groups received routine postoperative guidance care at the same time. Besides, the patients of the CFE group underwent a cervical functional exercise program after on the third day after ACDF. The evaluation was conducted preoperatively and at 1 week, 1 month and 6 months after surgery. The Visual Analogue Scale (VAS), Neck Disability Index (NDI) and Japanese Orthopaedic Association scores (JOA) were used to assess clinical outcomes and the safety was confirmed with routine postoperative radiological visits to ensure intervertebral stability. RESULTS: The CFE group reported lower neck pain scores on VAS at 1 month after surgery (P = 0.02) and higher postoperative scores by JOA at 1 month and 6 months, neck disability on NDI at 1 week, 1 month and 6 months after surgery (P < 0.05) compared to the UC group. For postoperative dysfunction, the CFE group had more significant changes than the UC group at 1 month and 6 months after surgery (P < 0.05). There was no statistical difference in cervical curves, fusion rate and fusion status between the two groups, and no revision surgery was recorded although a patient has one screw partially back out in UC group. CONCLUSION: Our study suggested that the cervical functional exercise could decrease cervical pain and improve postoperative function in patients after ACDF. It was a safe and effective treatment for postoperative rehabilitation. The use of a postoperative collar, especially for one or two-level ACDF may not be needed. PROTOCOL IDENTIFYING NUMBER: This trial was registered in the Chinese Clinical Trial Registry (registration number: ChiCTR1900025569) on 01/09/2019.

2.
Sci Rep ; 14(1): 13949, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886494

RESUMO

Iron in the leaching solution with high K+ and Na+ concentrations was usually precipitated as the typical hazardous and toxic jarosite residues. However, this method of treatment has been greatly restricted by increasingly strict environmental regulations. Here we propose that iron can be precipitated from the solution with high K+ and Na+ concentrations as recyclable hematite products by adjusting the concentration ratio of sodium and potassium ions in the solution. The transformation behavior of jarosite into hematite in high concentration potassium ion and sodium ion solution was explained based on collision theory. The results indicated that in instances where the concentration ratio of Na+/K+ is ≥ 4:1, the iron present in the solution can be effectively precipitated as a recyclable hematite product, as opposed to forming the conventional hazardous jarosite residue, even under conditions where the potassium ion concentration reaches levels as high as 4 g/L. On the other hand, thermodynamic and molecular dynamics simulations indicate that at a temperature of 185 °C, the decomposition transformation of Na-jarosite (32.64 kJ and 7.25 eV) is more energetically advantageous compared to that of K-jarosite (61.07 kJ and 15.31 eV). The results were verified by the leaching solution from smelting industry. The iron content in the residues is above 58%, the sulfur content is below 4%, the zinc content is below 1%, and the total iron concentration in the supernatant is about 4 g/L, reaching the production index of the smelting industry. The green, environmentally friendly, and recyclable separation of iron in a solution with high concentrations of potassium and sodium ions is achieved, which is of great significance for the treatment of iron-containing solution and wastewater in the chemical industry and metallurgy fields.

3.
BMC Musculoskelet Disord ; 25(1): 410, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38783277

RESUMO

PURPOSE: To compare the morphometry of paraspinal muscles in patients with degenerative spondylolisthesis (DS), isthmic spondylolisthesis (IS), and healthy individuals. METHODS: Thirty-seven pairs of DS patients were selected using propensity score matching with IS patients, while 37 healthy individuals matched for age, sex, and BMI were selected as controls. The relative cross-sectional area (rCSA), and relative functional cross-sectional area (rfCSA) of paraspinal muscles were measured, and the degree of fatty infiltration (FI) was calculated. Based on occupational differences, the patients were also divided into worker and farmer groups, and the same measurements were taken on them. RESULTS: At the L3/L4 level, the multifidus (MF) FI was greater in the DS and IS groups than in the control group, the erector spinae (ES) rfCSA was higher in the IS group than in the DS and control groups. At the L4/L5 level, MF rfCSA was smaller in the DS and IS groups than in the control group; ES rfCSA was higher in the IS group than in the DS and control groups. At the L5/S1 level, MF rfCSA was smaller in the DS and IS groups than in the control group; ES rfCSA was higher in the IS group than in the DS group. At the L3/L4, L4/L5 level, MF rfCSA were higher in the worker group than in the farmer group (p < 0.05). CONCLUSION: The morphological changes in paraspinal muscles in patients with DS were dominated by selective atrophy of the MF, while in patients with IS, the morphological changes in paraspinal muscle showed selective atrophy of the MF accompanied by compensatory hypertrophy of the ES. The surgeon should consider the morphological differences in paraspinal muscle between different types of lumbar spondylolisthesis when establishing the appropriate surgical program.


Assuntos
Vértebras Lombares , Músculos Paraespinais , Pontuação de Propensão , Espondilolistese , Humanos , Espondilolistese/diagnóstico por imagem , Espondilolistese/patologia , Músculos Paraespinais/patologia , Músculos Paraespinais/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Adulto , Estudos de Casos e Controles , Imageamento por Ressonância Magnética
4.
Waste Manag ; 181: 168-175, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38615500

RESUMO

The recovery of valuable metals from used lithium batteries is essential from an environmental and resource management standpoint. However, the most widely used acid leaching method causes significant ecological harm. Here, we proposed a method of recovering Li and Fe selectively from used lithium iron phosphate batteries by using low-concentration organic acid and completing the closed-loop regeneration. Low-concentration oxalic acid is used to carry out PO43-, which is significantly less soluble in aqueous solution than Li, two-stage selective leaching Li, where the leaching rate of Li reaches 99 %, and the leaching rate of Fe is only 2.4 %. The leach solution is then decontaminated. The solubility of Li3PO4 in aqueous solution is much smaller than that of Li2C2O4, which was required to recover Li to change the pH and Li can be recovered as Li3PO4; Fe can be retrieved as FeC2O4·2H2O, and re-prepared into lithium iron phosphate.


Assuntos
Compostos Férricos , Lítio , Ácido Oxálico , Fosfatos , Reciclagem , Ácido Oxálico/química , Fosfatos/química , Lítio/química , Reciclagem/métodos , Ferro/química , Fontes de Energia Elétrica
5.
Eur Spine J ; 33(4): 1504-1510, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38355769

RESUMO

PURPOSE: The study aimed to examine the consistency of vertebral bone quality (VBQ) scores for assessing osteoporosis across different etiologies and explore the predictive value of various VBQ scores for fragility vertebral fractures. METHODS: Patients with fragility fractures were matched by age and sex to patients with lumbar degeneration. VBQ scores were calculated in T1- and T2-weighted magnetic resonance imaging. Differential analysis of bone quality was performed based on etiology. RESULTS: A total of 96 inpatients were retrospectively enrolled. VBQT1 scores were only sensitive to osteoporotic bone in degenerative group (p < 0.01), failing to identify osteoporosis in fractured group (p > 0.05). For the degenerative group, the area under the curve (AUC) using the VBQT1 scores to differentiate osteoporosis was 0.72. After controlling the confounding variables, only VBQT2 scores were significantly higher in fractured group than degenerative group, with a greater AUC of 0.82 predicting fragility fractures. VBQT1 scores moderately correlated with femoral neck T-scores in degenerative group (r = -0.45, p < 0.01) but not in fractured group (r = -0.24, p > 0.05). VBQT2 scores were not associated with femoral neck T-scores (p > 0.05). CONCLUSION: This study is the first to evaluate the effectiveness of VBQs scores in assessing osteoporosis post-fracture. Only non-fractured patients' bone quality is fully susceptible to VBQT1 scores. While VBQT1 scores may not correlate with fragility fractures, VBQT2 scores present a viable alternative.


Assuntos
Osteoporose , Fraturas por Osteoporose , Humanos , Fraturas por Osteoporose/diagnóstico por imagem , Estudos Retrospectivos , Densidade Óssea , Vértebras Lombares/diagnóstico por imagem , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Imageamento por Ressonância Magnética/efeitos adversos
6.
Curr Mol Med ; 24(1): 123-133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37138491

RESUMO

BACKGROUND: Extensive deposition of extracellular matrix (ECM) in idiopathic pulmonary fibrosis (IPF) is due to hyperactivation and proliferation of pulmonary fibroblasts. However, the exact mechanism is not clear. OBJECTIVE: This study focused on the role of CTBP1 in lung fibroblast function, elaborated its regulation mechanism, and analyzed the relationship between CTBP1 and ZEB1. Meanwhile, the antipulmonary fibrosis effect and its molecular mechanism of Toosendanin were studied. METHODS: Human IPF fibroblast cell lines (LL-97A and LL-29) and normal fibroblast cell lines (LL-24) were cultured in vitro. The cells were stimulated with FCS, PDGF-BB, IGF-1, and TGF-ß1, respectively. BrdU detected cell proliferation. The mRNA expression of CTBP1 and ZEB1 was detected by QRT-PCR. Western blotting was used to detect the expression of COL1A1, COL3A1, LN, FN, and α-SMA proteins. An animal model of pulmonary fibrosis was established to analyze the effects of CTBP1 silencing on pulmonary fibrosis and lung function in mice. RESULTS: CTBP1 was up-regulated in IPF lung fibroblasts. Silencing CTBP1 inhibits growth factor-driven proliferation and activation of lung fibroblasts. Overexpression of CTBP1 promotes growth factor-driven proliferation and activation of lung fibroblasts. Silencing CTBP1 reduced the degree of pulmonary fibrosis in mice with pulmonary fibrosis. Western blot, CO-IP, and BrdU assays confirmed that CTBP1 interacts with ZEB1 and promotes the activation of lung fibroblasts. Toosendanin can inhibit the ZEB1/CTBP1protein interaction and further inhibit the progression of pulmonary fibrosis. CONCLUSION: CTBP1 can promote the activation and proliferation of lung fibroblasts through ZEB1. CTBP1 promotes lung fibroblast activation through ZEB1, thereby increasing excessive deposition of ECM and aggravating IPF. Toosendanin may be a potential treatment for pulmonary fibrosis. The results of this study provide a new basis for clarifying the molecular mechanism of pulmonary fibrosis and developing new therapeutic targets.


Assuntos
Fibrose Pulmonar Idiopática , Humanos , Camundongos , Animais , Bromodesoxiuridina/metabolismo , Bromodesoxiuridina/farmacologia , Fibrose Pulmonar Idiopática/genética , Pulmão , Fibroblastos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
7.
Front Bioeng Biotechnol ; 10: 1036223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36394034

RESUMO

Objective: The objectives of this study were to analyze the computed tomography (CT) scan imaging data of the cervical spine from healthy volunteers and to correlate the measurements to the dimensions of current cervical disc arthroplasty systems. Methods: A total of 130 participants (78 males and 52 females) with a mean age of 41.0 years (range 18.0-66.0 years) who had undergone computed tomography scans of the cervical spine were included. The linear parameters of the C3 to C7 levels, including anterior-posterior diameter (AP), middle disc height (DH), anterior disc height (ADH), posterior disc height (PDH) and center mediolateral diameter (ML), were measured. The analysis was conducted comparing different cervical levels, sexes, and age groups. Known dimensions from eight cervical disc arthroplasty systems were compared with the morphologic data. Results: A total of 520 vertebral segments were measured. The mean values for the measured parameters were as follows: anterior-posterior diameter 16.08 ± 1.84 mm, mediolateral diameter 16.13 ± 1.99 mm, anterior disc height 3.88 ± 1.11 mm, disc height 5.73 ± 1.00 mm, posterior disc height 2.83 ± 0.94 mm, and mediolateral diameter/anterior-posterior diameter 1.01 ± 0.13. All parameters except for posterior disc height were significantly different across the different cervical levels (p < 0.05). There were also significant sex differences in terms of the linear parameters. No differences were found in the majority of parameters among the different age groups (p > 0.05), except for anterior-posterior diameter at the C6/7 level. A comparison of the bone dimensions from the study data and the dimensions of the implants indicated the presence of a size mismatch in the currently available cervical disc prostheses. Conclusion: There is a large discrepancy between the cervical anatomical data of Chinese patients and the sizes of currently available prostheses. The dimensions collected in this study could be used to design and develop appropriate disc prostheses for Chinese patients.

8.
Eur Spine J ; 31(12): 3426-3432, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36057908

RESUMO

PURPOSE: To identify the ideal entry point for pediatric C2 pedicle screw and to obtain parameters of it for the indication of pediatric atlantoaxial fusion arthrodesis. METHODS: The pediatric cervical CT images were reconstructed into the 3D digital models and the C2 vertebrae were separated. The location of ideal entry point and screw placement related linear and angular parameters were assessed on the 3D digital models. RESULTS: A total of 214 pedicles from 107 C2 digital models were analyzed. The average entry point for C2 was 3.80 ± 2.78 mm medial to the lateral notch (LN) and 2.57 ± 1.70 mm superior to the LN. The average pedicle diameter (PD) was 6.02 ± 1.31 mm, and the average pedicle screw length (PSL) was 25.63 ± 3.46 mm. Statistical differences were found between different sex for PD and PSL (P < 0.05). As patient age increases, using the most lateral and inferior edge of the lateral mass as a reference marker, the entry point tends to move medial and cephalad, when using the LN as a reference marker, the entry point tends to move medial and slightly caudad. Univariate linear regression analysis suggested that these linear parameters were associated with age (P < 0.01). CONCLUSION: In this study, we found that the measurement results of C2 pedicle screw varied based on sex, laterality, and ages for children younger than 18 years. The entry point of the screws facilitating ideal trajectory tends to change in a linear way as a function of age. This information helps the surgeon to establish the specific anatomy related to C2 pedicle screw placement to facilitate fixation in the pediatric patients.


Assuntos
Articulação Atlantoaxial , Parafusos Pediculares , Fusão Vertebral , Humanos , Criança , Adolescente , Fusão Vertebral/métodos , Articulação Atlantoaxial/cirurgia , Tomografia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia
9.
Medicine (Baltimore) ; 101(29): e29605, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35866769

RESUMO

INTRODUCTION: Peripheral pulmonary lesions are encountered frequently in clinical practice. Accurate diagnosis of these lesions is of great importance for clinicians. Ultrasound-guided lung tissue puncture is a reliable method for diagnosing these lesions. OBJECTIVES: To investigate the application value of contrast-enhanced ultrasound (CEUS) combined with rapid on-site evaluation (ROSE) in the diagnosis of peripheral pulmonary focal lesions. METHODS: Eighty patients enrolled from July 2020 to June 2021 were divided into two groups: a conventional ultrasound group and a CEUS group. Both groups underwent diagnostic procedures guided by ROSE to improve the success rate of puncture sampling. The success rates and complications in both groups were compared. The results for lesion enhancement, time taken for the contrast agent to reach the lesions (AT) and lung tissues (L-AT), and the difference between these times (∆AT) were compared in the CEUS group. RESULTS: The success rate of biopsy in the CEUS group was 97.62%, which was significantly higher than that in the conventional ultrasound group (84%; P < .05). Puncture complications did not occur in the CEUS group and occurred in 5.26% of the cases in the conventional ultrasound group, but the difference was not statistically significant (P > .05). A comparison of enhancement of benign lesions and malignant lesions in the CEUS group showed a statistically significant difference (P < .05). The difference between the AT and ∆AT of benign and malignant lesions was statistically significant (P <.05). The optimal threshold of ∆AT was 2.05 s. CONCLUSION: CEUS combined with ROSE is a very important approach for biopsy in the diagnosis of peripheral pulmonary focal lesions. CEUS has definite clinical value in the diagnosis of benign and malignant lung lesions.


Assuntos
Meios de Contraste , Pulmão , Biópsia , Humanos , Pulmão/diagnóstico por imagem , Sensibilidade e Especificidade , Ultrassonografia/métodos
10.
Waste Manag ; 139: 116-123, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34959087

RESUMO

Blast furnace dust (BFD) contains ferrous and nonferrous metals and carbon, and is usually categorized as a typical secondary resource and hazardous waste produced by the iron-making process. The thermodynamic calculation and experimental investigation of the selective separation of zinc and iron/carbon from BFD via a NaCl-HCl-H2O system were carried out. Quantitative zinc and iron/carbon separation and recovery was achieved via a zinc-chloride (ZnCli2-i (i = 0, 1, 2, 3, 4)) cooperative leaching methodology using 3 mol/L NaCl at pH of 4, an L/S ratio of 4:1, a leaching temperature of 70 °C, a HCl concentration of 0.25 mol/L, and a leaching time of 2 h. Moreover, the total Cl- concentration used in for leaching was 2.09 mol (as concluded by the dosages of HCl and NaCl, and material). Results demonstrate that zinc was effectively leached from BFD, while the leaching of iron was hindered, in the acidic region. 93.2% of the zinc was extracted into a leaching solution containing 19.8 g/L zinc under the optimal conditions, and the ratio of the leaching agent to BFD was 300 mL to 75 g. The XRD and SEM-EDS analysis results of the residue reveal that ZnO and ZnS were leached, and the zinc-iron spinel (ZnFe2O4) was not leached and was present together with the iron oxide in the leaching residue. Iron and carbon in the leaching residue was enriched from 49.4% to 60.38%, and the iron and carbon were recovered as secondary resources that can be reused in the iron-making system.


Assuntos
Ferro , Zinco , Carbono , Poeira , Metalurgia , Zinco/análise
11.
Adv Clin Exp Med ; 29(7): 825-832, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32725971

RESUMO

BACKGROUND: Epidemiological studies and mice models have demonstrated that air pollution containing particulate matter smaller than 2.5 µm (PM2.5) exacerbates acute episodes of asthma in both children and adults. OBJECTIVES: To investigate the effect of continuous PM2.5 treatment on asthma regulation mechanism behind this effect. MATERIAL AND METHODS: In this study, the effects of continuous exposure to PM2.5 on asthma and eosinophil recruitment was compared to the effect of a single pre-ovalbumin (OVA)-sensitization exposure to PM2.5. Wild-type mice were either challenged once with PM2.5 + OVA before sensitization and asthma induction over a 27-day period, or with 5 times of PM2.5 + OVA treatment and sensitization/asthma induction over the same period. RESULTS: Continuous exposure to PM2.5 significantly increased total plasma immunoglobulin E (IgE), bronchial alveolar lavage fluid (BALF) cell numbers, eosinophils, and macrophages, leading to increased lung injury. This effect was regulated through increased production of chemokines and cytokines, such as interleukin (IL)-1ß, monocyte chemoattractant protein 1 (MCP-1), IL-12, IL-5, IL-13, and prostaglandin D2 (PGD2). Eosinophil recruitment during continuous PM2.5 treatment was regulated through phosphorylation of the JAK/STAT6 pathway. As this study shows, continuous PM2.5 treatment significantly worsens asthma as compared to single exposure to PM2.5 or OVA exposure alone. CONCLUSIONS: Our findings reveal that continuous exposure of PM2.5 exacerbates OVA-induced asthma in mouse lung through JAK-STAT6 signaling pathway.


Assuntos
Asma , Animais , Asma/induzido quimicamente , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Janus Quinases , Pulmão , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Material Particulado/toxicidade , Fator de Transcrição STAT6 , Transdução de Sinais
12.
Int J Clin Exp Pathol ; 8(10): 13739-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26722602

RESUMO

Asthma is a complex inflammatory disease involving the critical actions of several important cytokines. Epidemiological data show that obesity could increase the risk of asthma, and insulin resistance, or metabolic syndrome are an important risk factor for obesity asthma. Some studies identified that upstream of the transcription start site within the TNF-α gene promoter region-308 polymorphism was associated insulin resistance or metabolic disorders, while this site was closely related to asthma. But no research was performed to evaluate the influence of TNF-α-308G/A polymorphism on metabolic syndrome in asthmatic patients. Here, we recruited 248 asthmatic patients, who were separated into asthma with Mets/asthma without Mets groups and 226 matched healthy controls from Hebei Province to evaluate the influence of TNF-α-308G/A polymorphism on metabolic syndrome in asthmatic patients. Single nucleotide polymorphism of TNF-α-308 locus was genotyped using PCR-RFLP. Some biochemical variables were also determined. Our result showed that the genotypic and allelic frequency of rs1800629 did not show significant difference between asthmatic patients and normal controls. However, the frequency of A allele was significantly higher in asthma group with Mets (22.36%) than in controls (15.71%) (P = 0.02; OR = 0.647; 95% CI = 0.447-0.936). After analyzing the relationship between biochemical features of patients and genotype of TNF-α-308G/A, we found levels of LDL cholesterol, TNF-α and insulin, and HOMA-IR were significantly higher in the asthmatic patients carrying the GA and AA genotypes than in the carriers of GG genotype of rs1800629 (P = 0.029, P = 0.022, P = 0.043, respectively). Thus, our data suggested that TNF-α-308G/A variation was related to metabolic phenotype in asthma patients. Furthermore, we first identified TNF-α-308 A allele was the risk factor for asthmatic patients with Mets in Hebei population, China.


Assuntos
Asma/genética , Síndrome Metabólica/genética , Polimorfismo de Nucleotídeo Único/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Asma/complicações , China , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Insulina/metabolismo , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Obesidade , Mutação Puntual , Fatores de Risco , Fator de Necrose Tumoral alfa/sangue
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(2): 327-30, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24822394

RESUMO

The luminescence spectra of InGaN/GaN multiple quantum wells light-emitting diodes under low level injection current (<4 mA) during aging process was investigated for the first time. Comparing the electroluminescence (EL) spectra of LEDs before and after aging time it was found that the peak wavelength and the full width at half maximum (FWHM) decreased with stress time and the changes of EL spectrum had two different stages-drastic decrease at the early stress stage and slow decrease later showing the same trend with the output optical power of LEDs, which indicates that the effective polarization electric field of LEDs becomes weak during the aging process and the change has a clear correlation with the increase of the defects in the multiple quantum wells of LEDs. Electrical measurement revealed that junction capacitance (C(j)) under the same junction voltage (V(j) = 1.8 V) and the junction voltage (V(j)) with the same injection current 1 mA calculated by ac small-signal IV method increased along with aging time, which explicates that the carrier density under the same low injection increases as the aging time increases. Analyses indicate that the polarization field in the quantum well is more seriously screened by the increased carriers captured by defects activated during stress time, the weaker effective polarization electric field makes the tilt of the energy band smaller, the energy radiated through the band edge and the density of energy states of the band edge increase which leads to the behaviors of peak wavelength and the FWHM of InGaN/GaN multiple quantum wells LEDs under low level injection current.

14.
J Hazard Mater ; 176(1-3): 226-30, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19945217

RESUMO

Diffusion dialysis with a series of anion exchange membranes was used to recover H(2)SO(4) from an acid leach solution produced during the vanadium manufacturing process. The effects of sulfuric acid, FeSO(4) and VOSO(4) concentration, flow rate and flow rate ratio on the recovery of H(2)SO(4) were investigated. The results showed that sulfuric acid permeated well through the membranes used, while metal ions were efficiently rejected. The recovery of H(2)SO(4) increased as the sulfate concentration of the feed increased and the flow rate ratio of water to feed increased. More than 80% of the H(2)SO(4) could be recovered from the leach solution which contained 61.7 g/L free H(2)SO(4), 11.2 g/L Fe and 4.60 g/L V at a flow rate of 0.19x10(-3) m(3)/h m(2). V and Fe ion rejection were within 93-95 and 92-94%, respectively. A preliminary economic evaluation revealed that an investment in this process could be recovered within 27 months.


Assuntos
Indústria Química , Conservação dos Recursos Naturais/métodos , Ácidos Sulfúricos/isolamento & purificação , Ácidos , Diálise , Difusão , Resíduos Industriais/prevenção & controle , Troca Iônica , Soluções , Vanádio
15.
IUBMB Life ; 60(8): 534-40, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18548556

RESUMO

Loss of 14-3-3sigma expression mainly by methylation-mediated silencing has been reported in several human cancers, but the methylation status of 14-3-3sigma in human renal carcinoma is rarely studied so far. In this report, 14-3-3sigma expression was first examined by RT-PCR and immunohistochemistry, and further we investigated the methylation status by methylation-specific PCR and the correlation between 14-3-3sigma expression and its methylation. We found 14-3-3sigma expression was lost in 27 of 31 renal tissues including 16 renal carcinoma tissues, eight para-cancerous kidney tissues and seven normal kidney tissues. Among 16 renal carcinoma tissues, 14 cases had complete hypermethylation of 14-3-3sigma. Eight para-cancerous kidney tissues were almost completely methylated except one case had both methylation and unmethylation. Among seven normal kidney tissues, five cases had partial methylation, and the other two cases were completely methylated. In addition, 14-3-3sigma mRNA had weak expression in OS-RC-2 cells, but it increased with gradual demethylation after treatment by a demethylation agent, 5-aza-2'-deoxycytidine. In general, 14-3-3sigma mRNA was mostly unexpressed, and its DNA frequently hypermethylated within 14-3-3sigma coding region was closely associated with the gene silencing in cancerous and para-cancerous kidney tissues. 14-3-3sigma was also frequently methylated and almost silencing in normal kidney tissues. However, the methylation frequency was gradually reinforced with the extent of malignancy from normal to para-cancerous and cancerous kidney tissues.


Assuntos
Proteínas 14-3-3/metabolismo , Carcinoma/metabolismo , Metilação de DNA , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Renais/metabolismo , Linhagem Celular Tumoral , Ilhas de CpG/genética , Primers do DNA/genética , Humanos , Imuno-Histoquímica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
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