Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
Signal Transduct Target Ther ; 9(1): 107, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38697972

RESUMO

Cholangiocarcinoma (CCA) is a highly malignant biliary tract cancer with currently suboptimal diagnostic and prognostic approaches. We present a novel system to monitor CCA using exosomal circular RNA (circRNA) via serum and biliary liquid biopsies. A pilot cohort consisting of patients with CCA-induced biliary obstruction (CCA-BO, n = 5) and benign biliary obstruction (BBO, n = 5) was used to identify CCA-derived exosomal circRNAs through microarray analysis. This was followed by a discovery cohort (n = 20) to further reveal a CCA-specific circRNA complex (hsa-circ-0000367, hsa-circ-0021647, and hsa-circ-0000288) in both bile and serum exosomes. In vitro and in vivo studies revealed the three circRNAs as promoters of CCA invasiveness. Diagnostic and prognostic models were established and verified by two independent cohorts (training cohort, n = 184; validation cohort, n = 105). An interpreter-free diagnostic model disclosed the diagnostic power of biliary exosomal circRNA signature (Bile-DS, AUROC = 0.947, RR = 6.05) and serum exosomal circRNA signature (Serum-DS, AUROC = 0.861, RR = 4.04) compared with conventional CA19-9 (AUROC = 0.759, RR = 2.08). A prognostic model of CCA undergoing curative-intent surgery was established by calculating early recurrence score, verified with bile samples (Bile-ERS, C-index=0.783) and serum samples (Serum-ERS, C-index = 0.782). These models, combined with other prognostic factors revealed by COX-PH model, enabled the establishment of nomograms for recurrence monitoring of CCA. Our study demonstrates that the exosomal triple-circRNA panel identified in both bile and serum samples serves as a novel diagnostic and prognostic tool for the clinical management of CCA.


Assuntos
Colangiocarcinoma , Exossomos , RNA Circular , Humanos , RNA Circular/genética , RNA Circular/sangue , Colangiocarcinoma/genética , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/sangue , Colangiocarcinoma/patologia , Exossomos/genética , Masculino , Feminino , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Pessoa de Meia-Idade , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/patologia , Prognóstico , Colestase/genética , Colestase/diagnóstico , Colestase/sangue
2.
BMC Cancer ; 24(1): 426, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584263

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the 3rd most common malignancy with the liver being the most common site of metastases. The recurrence rate of colorectal liver metastases (CRLM) after liver resection (LR) is notably high, with an estimated 40% of patients experiencing recurrence within 6 months. In this context, we conducted a meta-analysis to synthesize and evaluate the reliability of evidence pertaining to prognostic factors associated with early recurrence (ER) in CRLM following LR. METHODS: Systematic searches were conducted from the inception of databases to July 14, 2023, to identify studies reporting prognostic factors associated with ER. The Quality in Prognostic Factor Studies (QUIPS) tool was employed to assess risk-of-bias for included studies. Meta-analysis was then performed on these prognostic factors, summarized by forest plots. The grading of evidence was based on sample size, heterogeneity, and Egger's P value. RESULTS: The study included 24 investigations, comprising 12705 individuals, during an accrual period that extended from 2007 to 2023. In the evaluation of risk-of-bias, 22 studies were rated as low/moderate risk, while two studies were excluded because of high risk. Most of the studies used a postoperative interval of 6 months to define ER, with 30.2% (95% confidence interval [CI], 24.1-36.4%) of the patients experiencing ER following LR. 21 studies were pooled for meta-analysis. High-quality evidence showed that poor differentiation of CRC, larger and bilobar-distributed liver metastases, major hepatectomy, positive surgical margins, and postoperative complications were associated with an elevated risk of ER. Additionally, moderate-quality evidence suggested that elevated levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA199), lymph node metastases (LNM) of CRC, and a higher number of liver metastases were risk factors for ER. CONCLUSION: This review has the potential to enhance the efficacy of surveillance strategies, refine prognostic assessments, and guide judicious treatment decisions for CRLM patients with high risk of ER. Additionally, it is essential to undertake well-designed prospective investigations to examine additional prognostic factors and develop salvage therapeutic approaches for ER of CRLM.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Hepatectomia , Prognóstico , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos
3.
Int Wound J ; 21(3): e14715, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494179

RESUMO

To systematically explore the effects of minimally invasive plate osteosynthesis (MIPO) versus intramedullary nail (IMN) on wound infection and wound healing in patients with distal tibia fractures. A computerised search of PubMed, Web of Science, Cochrane Library, Embase, Wanfang, China Biomedical Literature Database (CBM) and China National Knowledge Infrastructure databases was performed, from their inception to October 2023, to identify relevant studies on the application of MIPO and IMN in patients with distal tibial fractures. The quality of the included literature was evaluated by two researchers based on inclusion and exclusion criteria, and basic information of the literature was collected, with wound infection, postoperative complications and wound healing time as the main indicators for analysis. Stata 17.0 software was applied for analysis. Overall, 23 papers and 2099 patients were included, including 1026 patients in the MIPO group and 1073 patients in the IMN group. The results revealed, when compared with IMN treatment, patients with distal tibia fractures who underwent MIPO treatment had a lower incidence of postoperative complications (OR = 0.33, 95% CI: 0.25-0.42, p < 0.001) and a shorter wound healing time (SMD = -1.00, 95% CI: -1.51 to -0.49, p < 0.001), but the incidence of postoperative wound infection was higher (OR = 2.01, 95% CI: 1.35-3.01, p = 0.001). Both MIPO and IMN are excellent treatments for distal tibia fractures. MIPO is effective in reducing the incidence of complications as well as shortening the time of wound healing time but increases the risk of wound infection. In clinical practice, surgeons can make individual choices based on the patient's wishes and proficiency in both techniques.


Assuntos
Fraturas do Tornozelo , Fixação Intramedular de Fraturas , Fraturas da Tíbia , Humanos , Fixação Intramedular de Fraturas/métodos , Consolidação da Fratura , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fixação Interna de Fraturas/efeitos adversos , Fraturas da Tíbia/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Resultado do Tratamento
4.
J Biophotonics ; 17(3): e202300332, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38041248

RESUMO

The erbium-doped yttrium aluminum garnet (Er: YAG) laser has been successfully applied in caries removal; however, little is known about proper parameters of Er: YAG laser on different conditions of caries removal, especially the influence of Er: YAG irradiation on human dental pulp cells (hDPCs). Here, we tested the effects of Er: YAG laser at different output energy levels (100, 200, 300, 400, and 500 mJ) on biobehaviors of hDPCs. To simulate clinical deep caries conditions, hDPCs were cultured on the pulpal side of 500-µm-thick dentin disks in an in vitro pulp chamber model. Temperature change, structural change, and ablation depth of dentin disk were also recorded. The findings suggested that the biological behaviors of hDPCs are strongly correlated with the energy output of the Er: YAG laser. Er: YAG laser irradiation at 100 mJ may be proper and safe for deep caries removal since it would not cause any adverse effect on hDPCs biobehaviors.


Assuntos
Cárie Dentária , Lasers de Estado Sólido , Humanos , Dentina , Suscetibilidade à Cárie Dentária , Polpa Dentária , Cavidade Pulpar , Cárie Dentária/radioterapia
5.
Eur J Surg Oncol ; 49(11): 106982, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37487828

RESUMO

BACKGROUND: Perihilar cholangiocarcinoma (pCCA) is a type of cancer that has a high rate of recurrence after curative-intent surgery, with about half of all recurrences occurring within the first year. The primary aim of this study was to identify prognostic factors (PFs) for early recurrence (ER, within 12 months) after surgery. METHODS: Systematic searching was conducted from database inception to September 28th, 2022, with duplicate independent review and data extraction. Data on eight predefined PFs were collected, and meta-analysis was performed on PFs for ER, summarized using forest plots. RESULTS: The study enrolled 11 studies comprising 2877 patients. In the risk-of-bias assessment, seven studies were rated as low risk and four as moderate risk. More than 34.3% (95% confidence interval [CI], 26.1-42.5%) of the patients experienced ER after curative-intent pCCA resection. Of the PFs, vascular invasion (HR, 2.41; 95% CI, 1.47-3.95; OR, 1.60; 95% CI, 1.17-2.18), lymph node metastases (HR, 2.54; 95% CI, 1.92-3.37; OR, 4.26; 95% CI, 2.40-7.57), and R1 resection (HR, 3.27; 95% CI, 1.81-5.92; OR, 2.40; 95% CI, 1.36-4.22) were associated with an increased hazard for ER. The combined OR values also showed that tumor size, poor tumor differentiation, and perineural invasion were linked to an elevated risk of ER, but all of them had apparent heterogeneity. CONCLUSION: These findings from the review could be used to plan surveillance of ER and guide post-operative individualized management in pCCA. Furthermore, prospective studies are needed to explore more prognostic factors for ER of pCCA.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Humanos , Tumor de Klatskin/cirurgia , Tumor de Klatskin/patologia , Prognóstico , Resultado do Tratamento , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Hepatectomia , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123182, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37517268

RESUMO

van der Waals (vdW) heterojunctions based on two-dimensional (2D) materials, graphene and transition metal dichalcogenides (TMDs), are a research hotspot for future optoelectronic and exciton devices. Bond-free vdW interactions are key to 2D material heterojunction device reliability and stability. However, most of the current research on 2D stacked materials heterostructures mainly focuses on optical properties and electronic structure. Furthermore, vdW interaction in 2D heterostructures is studied and understood on the basis of qualitative description and energy ranges from the literature. There are few studies on the nature of vdW interaction based on practical calculations of the quantitative strength and microscopic mechanism of vdW interaction between 2D stacked materials. Therefore, this paper explores the vdW interaction between 2D material stacked bilayer structures, including bilayer graphene, graphene/MoS2 and graphene/WS2 heterostructures, focusing on quantitative analysis of the energy components of the vdW interaction. We first visually observed the weak interactions in the three stacked bilayer structures through noncovalent interaction (NCI) analysis, and found that the interactions are concentrated in the binding region between the two-layer structures. We mainly decomposed the weak interaction energy in the three 2D material bilayer heterostructures through energy decomposition analysis based on the force field (EDA-FF) method and obtained the energy values and proportions of the three components-electrostatic energy, exchange repulsion energy and dispersion energy of the total binding energy between the 2D stacked bilayer structures. The vdW interaction energy is the sum of the exchange repulsion energy and dispersion energy, and the dispersion energy of the vdW interaction accounts for more than 60% of the binding energy of the weak interaction between the 2D bilayer stacked structures. The vdW strengths in the bilayer structures are on the order of 177.07, 123.85, and 133.93 kJ/mol, approxmately 1-2 orders of magnitude larger than the classically defined vdW energies of 0.1-10 kJ/mol. Furthermore, we calculate the density of states of the three 2D stacked structures, and further obtained HOMO-LOMO information; to further understand the electronic structures of the graphene/MoS2 and graphene/WS2 heterostructures, we calculated their optical absorption spectra and electron circular dichroism (ECD) spectra. According to the calculation results, the two heterostructures have strong absorption peaks in the visible region, and the charge transfer forms at the strong absorption peak can be determined according to the charge transfer diagram. The ECD spectra indicate that the configurations of the graphene/MoS2 and graphene/WS2 heterostructures have large chirality. Our work contributes to a deeper understanding of the nature of the weak interactions and optical properties in 2D stacked materials, which plays a fundamental role in promoting the construction of stable 2D heterostructure configurations and the development of multifunctional 2D devices. The research is conducive to further promoting the basic research and practical development of strong optoelectronic and excitonic 2D heterojunctions devices.

7.
BMC Cancer ; 23(1): 378, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37098481

RESUMO

BACKGROUND: Malignant tumors of the biliary system are characterized by a high degree of malignancy and strong invasiveness, and they are usually diagnosed at late stages with poor prognosis. For patients with advanced biliary tract cancer, chemotherapy and targeted therapy are two of the options available to improve prognosis and delay tumor progression. This study aimed to comprehensively evaluate the safety and effectiveness of various chemotherapy schemes for the treatment of advanced biliary tract cancer in published systematic reviews and meta-analyses (SRoMAs). METHODS: An umbrella review method was adopted, which aims to summarize the existing evidence from multiple studies around a research topic. SRoMAs up to April 9, 2022, were identified using PubMed, Web of Science, the Cochrane database, and manual screening. Eligible studies were screened according to inclusion and exclusion criteria. This study had been registered at PROSPERO (CRD42022324548). For each eligible study, we extracted the data of general characteristics and the main findings. The methodological quality of the included studies were assessed by the AMSTAR2 scale, and the quality of evidence was evaluated by the GRADE tools. RESULTS: A total of 1833 articles were searched; 14 unique articles with 94 outcomes were identified by eligibility criteria. The incidence of skin rash (RR = 18.11, 95% CI 5.13-63.91, GRADE: Moderate) and diarrhea (RR = 2.48, 95% CI 1.2-5.10, GRADE: Moderate) was higher in patients receiving gemcitabine-based chemotherapy plus targeted therapy than in patients receiving gemcitabine monotherapy. The number of patients receiving gemcitabine-based chemotherapy who developed leukopenia (OR = 7.17, 95% CI 1.43-36.08, GRADE: Moderate), anemia (OR = 7.04, 95% CI 2.59-19.12, GRADE: High), thrombocytopenia (RR = 2.45, 95% CI 1.39-4.32, GRADE: Moderate), and neutropenia (RR = 3.30, 95% CI 1.04-10.50, GRADE: Moderate) was significantly higher than that of patients who received gemcitabine-free regimens. In addition, patients receiving S-1 monotherapy had significantly better ORR (RR = 2.46, 95% CI 1.27-4.57, GRADE: Moderate) than patients receiving S-1 + gemcitabine. Patients receiving fluoropyrimidine-based chemotherapy had longer OS (HR = 0.83, 95% CI 0.7-0.99, GRADE: Moderate), higher DCR (0R = 5.18, 95% CI 3.3-10.23, GRADE: Moderate), and higher ORR (0R = 3.24, 95% CI 1.18-8.92, GRADE: Moderate) compared with patients who received 5-FU/LV monotherapy or supportive therapy. Surprisingly, we found evidence that gemcitabine-based chemotherapy did not improve postoperative patients' OS (HR = 0.91, 95% CI 0.74-1.12, GRADE: Moderate) when compared with best supportive care. CONCLUSIONS: This study comprehensively evaluated the safety and efficacy of chemotherapy or targeted therapy regimens for advanced biliary tract cancer and found 11 outcomes with "Moderate" or "High" levels; however, most of the outcomes were still at "low" or "very low" levels. More randomized controlled studies are needed in the future to further summarize high levels of evidence.


Assuntos
Neoplasias do Sistema Biliar , Trombocitopenia , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/patologia , Gencitabina , Trombocitopenia/etiologia
8.
Environ Sci Pollut Res Int ; 30(14): 40230-40241, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36607569

RESUMO

The addition of an arsenite-chloride solution into an arsenite-sulfate solution is extremely beneficial for the removal of As(III) via Fe(III) salt precipitation at pH 2.3. However, the applicability of this method to complicated high-As(III) metallurgical wastewaters still requires further verification. This work investigated the effects of nitrate and Fe/As molar ratio on As(III) immobilization using Fe(III) in three acid radical media including sulfate, chloride, and nitrate at pH 2.3. Our results indicated that 72.1‒93.5% of As(III) was precipitated, which was 5‒10% less than those obtained in the nitrate-free systems. The Fe/As molar ratio of 4 was the optimal condition with an average of 93% As(III) removal based on a broad sulfate/chloride molar ratio range (1:1‒16). However, a maximum of 96% As(III) removal was observed under the Fe/As molar ratio of 1.5 and the sulfate/chloride condition of 1:16. The negative correlation between complexation and precipitation was attributed to the enhanced initial complexation by the synergistic effect of the mononitratoiron complex and FeH2AsO32+. The variation of Fe/As molar ratios resulted in the diverse solid species, thus further affecting the As(III) removal efficiency. Despite producing tooeleite as a major As(III) host phase, ferrihydrite and poorly crystalline ferric arsenite hydroxysulfate formed simultaneously at the Fe/As molar ratio of 4 participated in As(III) immobilization compared with the solid products at Fe/As molar ratios ≤ 2.


Assuntos
Arsenitos , Arsenitos/análise , Compostos Férricos/química , Sulfatos , Cloretos , Águas Residuárias , Nitratos , Ferro/química , Óxidos de Enxofre , Oxirredução
9.
Materials (Basel) ; 15(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36499991

RESUMO

Compared with the post-treatment of pollutants, such as the removal of phosphate from wastewater, it is more important to develop effective emission control strategies to reduce phosphate pollution. Phosphogypsum (PG) is a typical solid waste byproduct of phosphate production and contains high amounts of residual phosphate. In order to control the phosphate emissions during the recycling of PG aggregates for cemented backfill, another solid waste product­iron tailings (ITs)­was added during the preparation of backfill slurry. The results showed that the ITs effectively accelerated the phosphate removal in cemented PG backfill, enabling the quick reduction in the phosphate concentration to the discharge standard (<0.5 mg/L) within 15 min. This means that the emissions of phosphate to bleeding water were effectively controlled. The adsorption experiment showed that phosphate was adsorbed by the ITs, and the adsorption data fitted well with the Langmuir adsorption model (R2 = 0.98) and pseudo-second-order kinetic model (R2 = 0.99), indicating that the phosphate adsorption of ITs was a monolayer chemical adsorption. Furthermore, an unconfined compressive strength (UCS) test was performed on the backfill with the addition of ITs. Compared to the control group (without ITs), the UCS of backfill with 20% ITs increased from 1.08 MPa to 1.33 MPa, indicating that the addition of solid waste could be beneficial to the strength development of the backfill by mitigating the interference of phosphate with the hydration process. The backfill cured for 28 d was selected for the toxic leaching test, and the phosphate concentration in the leachates was always below 0.02 mg/L, indicating that ITs can effectively immobilize phosphate in backfill for a long time.

10.
Sci Total Environ ; 848: 157719, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35914597

RESUMO

The factors and mechanisms affecting the fate of the associated Cd during the Fe(II)-activated Cd-bearing ferrihydrite transformation remain poorly understood. Herein we have conducted a series of batch reactions containing ferrihydrite with diverse pH values and initial Fe(II) and Cd concentrations coupled with chemical analyses and spectroscopic examination on the transformation products to probe the mechanisms of the Cd partitioning and the processes of Fe(II)-activated Cd-bearing ferrihydrite transformation under anaerobic conditions. Chemical analyses, Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD) results show that the initial Fe(II) and Cd concentrations as well as pH values all have significant effects on the rates and pathways of ferrihydrite transformation. Increasing Cd loading enhances the inhibition of the Fe(II)-activated ferrihydrite transformation rates. High Cd loading alters the Fe(II)-activated ferrihydrite transformation pathways by hindering the recrystallization of both ferrihydrite to more stable iron minerals and the newly formed lepidocrocite to goethite. Chemical analyses show that the release of Cd to solutions during ferrihydrite transformation is accompanied by a reduction in the 0.4 M HCl extractable Cd fraction and that a significant amount of the released Cd is transformed to a 0.4 M HCl unextractable form. Moreover, enhanced Cd release during the Fe(II)-activated ferrihydrite transformation is observed by reducing the pH value or increasing the initial Cd concentration. Results from synchrotron X-ray absorption spectroscopy (XAS) confirm that the majority of the 0.4 M HCl unextractable Cd form is associated with structural incorporation into the recrystallized iron (hydr)oxides via isomorphous substitution for Fe(III). These findings not only provide molecular-level understanding on the behavior of Cd under natural anoxic environments, but also are useful in predicting the geochemical cycling of Cd and developing long-term Cd contaminant management strategies.


Assuntos
Compostos Férricos , Ferro , Anaerobiose , Cádmio , Compostos Férricos/química , Compostos Ferrosos , Ferro/química , Minerais/química , Oxirredução , Óxidos , Pós
11.
BMC Med Genomics ; 15(1): 132, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35706030

RESUMO

BACKGROUND: Fat mass and obesity-related (FTO) mRNA was downregulated in osteonecrosis patients. The study aimed to evaluate the correlation between FTO polymorphisms and the susceptibility of osteonecrosis of the femoral head (ONFH). METHODS: Six polymorphisms in FTO were genotyped via the Agena MassARRAY in 498 ONFH patients and 498 healthy controls. Multiple genetic models were used to assess the correlation between FTO polymorphisms and ONFH risk by SNPStats. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using a logistic regression model adjusted by age, gender, smoking and drinking. RESULTS: The risk-increasing association of rs62033406 A>G with ONFH was found (OR = 1.25, 95% CI 1.05-1.50, p = 0.014). Specially, FTO rs62033406 A>G was related to the risk of ONFH in the subgroup at age > 51 years (OR = 1.25, p = 4.00 × 10-4), females (OR = 1.74, p = 1.00 × 10-4), smokers (OR = 1.82, p = 0.005) and drinkers (OR = 1.89, p = 0.002), respectively. The best multi-loci model was the five-loci model, a combination of rs9930333 T>G, rs1558902 T>A, rs56094641 A>G, rs3751812 G>T, and rs62033406 A>G (testing accuracy, 0.5351; p = 0.0004; cross-validation consistency, 10/10). CONCLUSION: Our study first revealed that FTO rs62033406 A>G was a risk factor for ONFH among the Chinese Han population, which might provide the new candidate gene for elucidating the pathogenesis of ONFH.


Assuntos
Necrose da Cabeça do Fêmur , Cabeça do Fêmur , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Estudos de Casos e Controles , China/epidemiologia , Feminino , Necrose da Cabeça do Fêmur/genética , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
12.
Chemosphere ; 301: 134665, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35452640

RESUMO

Ubiquitous co-existence of arsenic (As) and cadmium (Cd) in smelting operations and mine drainage presents a major challenge to the environment. Fe(II)-induced ferrihydrite transformation into secondary, more crystalline minerals often controls the geochemical behavior of associated contaminants including arsenate (As(V)) and Cd(II) in natural and contaminated environments. However, the fate of co-existent As(V) and Cd(II) and the underlying mechanism during this transformation process remain unclear. In this contribution, ferrihydrite containing co-precipitated Cd(II) and As(V) with Fe(II) under diverse pH conditions has been investigated. Results from powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), and Raman spectra show that the co-existence of As(V) and Cd(II) significantly retards the transformation rates of As(V)/Cd(II)-bearing ferrihydrite to more stable iron oxides and reduces that from the newly formed lepidocrocite to goethite. Compared to Cd(II), the co-existent As(V) has stronger influence on the compositions of the transformation products. Chemical analysis shows that phosphate-unextractable As(V) and 0.4 M HCl unextractable Cd(II) both increase as the reaction proceeds during the recrystallization of As(V)/Cd(II)-bearing ferrihydrite, indicating that both As(V) and Cd(II) partially transform to a more stable phase. The co-existent Cd(II) has negligible effects on the As(V) redistribution, but the co-existent As(V) at high loadings has a significant modification in the distribution of Cd(II) during the transformation, which reduces the liberation of Cd(II) into solution, thus decreasing the mobility of Cd(II). These findings have important implications for understanding the mobility and fate of the co-existent As(V) and Cd(II) under natural anoxic environments, remediating the co-existent contaminants, and predicting the long-term behavior of As(V) and Cd(II) in natural and contaminated environments.


Assuntos
Arsênio , Cádmio , Compostos Férricos/química , Compostos Ferrosos , Ferro/química , Minerais/química , Oxirredução
13.
Appl Opt ; 61(8): 2096-2102, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35297901

RESUMO

X-ray mirrors with high focusing performance are extensively used in the synchrotron radiation field. Especially for vertical reflecting bendable mirrors, many elements such as gravity, extended parts used for the bending mechanism, etc., usually affect the surface shape precision. There are no effective methods to remove all these errors at this point. However, an iteration method can be adopted to solve this problem. In this paper, a novel, to the best of our knowledge, iteration method on decreasing the error between the practice surface shape and the desired one is proposed. Not only can the precision of the surface shape be realized by this method, but also computational efficiency. Errors induced by gravity can be compensated for by an analytical method, while errors caused by the extended parts should be eliminated by a numerical method. Therefore, two main kinds of errors-gravity and parts of clamping-can be removed by iteration. Some examples are presented to illustrate the advantages of this method by comparison with the regular one.

15.
Clin Gastroenterol Hepatol ; 20(2): e168-e181, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33220526

RESUMO

BACKGROUND & AIMS: Although current quality indicators of colonoscopy recommend 6 minutes as the minimum standard for withdrawal time (WT), the impact of a WT longer than 6 minutes on neoplasia detection is unclear. METHODS: A multicenter randomized controlled trial involving 1027 patients was conducted from January 2018 to July 2019. Participants were randomly divided into a 9-minute (n = 514) and 6-minute (n = 513) WT group, and a timer was used to adjust the withdrawal speed. The primary outcome was the adenoma detection rate (ADR). RESULTS: Intention-to-treat analysis showed a significantly higher ADR in the 9-minute versus 6-minute WT group (36.6% vs. 27.1%, P = .001). Prolonging WT from 6 to 9 minutes significantly increased ADR of the proximal colon (21.4% vs. 11.9%, P < .001) as well as of the less experienced colonoscopists (36.8% vs. 23.5%, P = .001). Improvements were also observed in the polyp detection rate (58.0% vs. 47.8%, P < .001), and mean number of polyps and adenomas detected per colonoscopy (1.1 vs. 0.9, P = .002; 0.5 vs. 0.4, P = .008, respectively). The higher ADRs in 9-minute WT were also confirmed by the per-protocol (PP) analysis and subgroup analyses, with an increased rate of sessile serrated lesion detection in the 9-minute WT by PP analysis (4.0% vs. 1.3%, P = .04). Multivariate logistic regression demonstrated that the 9-minute WT was independently associated with increased ADR (P = .005). CONCLUSIONS: Prolonging WT from 6 to 9 minutes significantly improved ADR, especially in the proximal colon and for less experienced colonoscopists. A 9-minute WT benchmark should be considered as one of the quality indicators of colonoscopy. ClinicalTrials.gov (identifier, NCT03399045).


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Pólipos , Adenoma/diagnóstico , Pólipos do Colo/diagnóstico , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Humanos
16.
World J Gastrointest Surg ; 13(10): 1202-1215, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34754388

RESUMO

BACKGROUND: Immunoinflammatory markers such as the peripheral blood neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) have gained considerable attention as prognostic markers in gastrointestinal stromal tumors (GISTs). AIM: To assess the prognostic value of Onodera's Prognostic Nutritional Index (OPNI) for GISTs. METHODS: All patients who had undergone surgical resection for a primary, localized GIST from 2009 to 2016 at our cancer center were initially and retrospectively identified. Recurrence-free survival (RFS) was calculated by the Kaplan-Meier method and compared by the log-rank test. We used multivariate Cox proportional hazard regression models to identify associations with outcome variables. RESULTS: A total of 235 GISTs were identified and included for analysis under our inclusion criteria. Univariate and multivariate analyses both identified the OPNI as an independent prognostic marker, and the OPNI was associated with the primary site, tumor size, mitotic index, tumor rupture, necrosis, and modified NIH risk classification. Low OPNI (< 51.30; hazard ratio = 5.852; 95% confidence interval: 1.072-31.964; P = 0.0414) was associated with worse RFS. The 2- and 5-year RFS rates of the patients with a low OPNI were 92.83% and 76.22%, respectively, whereas 100% and 98.41% were achieved by the patients with a high OPNI. CONCLUSION: The preoperative OPNI is a novel and useful prognostic marker for GISTs.

17.
Sci Total Environ ; 778: 146424, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030383

RESUMO

The toxicity and mobility of antimony (Sb) are strongly influenced by the redox transformation of widely spread 2-line ferrihydrite (Fh) in natural soils and sediments. This study investigated the transformation and redistribution of adsorbed antimonite (Sb(III)) during Fe(II)-catalyzed recrystallization of Fh under anaerobic conditions. X-ray diffraction (XRD), transmission electron microscopy (TEM), and synchrotron based X-ray absorption spectroscopy (XAS) were utilized to characterize the mineralogy and morphology of generated minerals as well as the speciation of Sb and Fe. Chemical analysis and Sb LIII-edge XANES spectra demonstrated that a great part of Sb(III) (80%-90%) was oxidized to Sb(V) by reactive oxygen species (ROS) during the Fe(II)-catalyzed transformation of Fh. Chemical extraction results showed that the mobility of Sb was significantly reduced with 50%-70% of initially adsorbed Sb(III) transformed to phosphate-unextractable phase. Antimony K-edge EXAFS analysis showed the SbO6 octahedra were incorporated into secondary minerals by substituting the Fe atoms. Our findings shed new light on the understanding of the geochemical behavior of Sb(III) under anoxic conditions.

18.
J Environ Sci (China) ; 94: 147-160, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563479

RESUMO

The ubiquitous arsenic in groundwater poses a great risk to human health due to its environmental toxicity and carcinogenicity. In the present work, a new adsorbent, δ-MnO2 modified activated carbon, was prepared, and its performance for the uptake of arsenate and arsenite species from aqueous solutions was investigated by batch experiments. Various techniques, including FESEM-EDX, p-XRD, XPS and BET surface area analysis, were employed to characterize the properties of the adsorbent and the arsenic adsorption mechanisms. The results showed that δ-MnO2 covered on the surface and padded in the pores of the activated carbon. Adsorption kinetic studies revealed that approximately 90.1% and 76.8% of As(III) and As(V), respectively, were removed by the adsorbent in the first 9 hr, and adsorption achieved equilibrium within 48 hr. The maximum adsorption capacities of As(V) and As(III) at pH 4.0 calculated from Langmuir adsorption isotherms were 13.30 and 12.56 mg/g, respectively. The effect of pH on As(V) and As(III) removal was similar, and the removal efficiency significantly reduced with the increase of solution pH. Arsenite oxidation and adsorption kinetics showed that the As(V) concentration in solution due to As(III) oxidation and reductive dissolution of MnO2 increased rapidly during the first 12 min, and then gradually decreased. Based on the XPS analysis, nearly 93.3% of As(III) had been oxidized to As(V) on the adsorbent surface and around 38.9% of Mn(IV) had been reduced to Mn(II) after As(III) adsorption. This approach provides a possible method for the purification of arsenic-contaminated groundwater.


Assuntos
Arsênio , Poluentes Químicos da Água/análise , Purificação da Água , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Compostos de Manganês , Óxidos , Água
19.
J Appl Biomater Funct Mater ; 18: 2280800020903630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32421424

RESUMO

This study was to develop a feasible and safe animal model for minimally invasive injectable lumbar interbody fusion using a novel biomaterial, mineralized collagen-polymethylmethacrylate bone cement (MC-PMMA), with unilateral pedicle screw fixation in an in vivo goat model. Eight goats (Capra aegagrus hircus) were divided into three groups: MC-PMMA, unmodified commercial-polymethylmethacrylate bone cement (UC-PMMA), and a control group (titanium cage filled with autogenous bone, TC-AB). Each group of goats was treated with minimally invasive lumbar interbody fusion at the L3/L4 and L5/L6 disc spaces (injected for MC-PMMA and UC-PMMA, implanted for TC-AB). The pedicle screws were inserted at the L3, L4, L5, and L6 vertebrae, respectively, and fixed on the left side. The characteristics of osteogenesis and bone growth were assessed at the third and the sixth month, respectively. The methods of evaluation included the survival of each animal, X-ray imaging, and 256-layer spiral computed tomography (256-CT) scanning, imaged with three-dimensional microfocus computed tomography (micro-CT), and histological analysis. The results showed that PMMA bone cement can be extruded smoothly after doping MC, the MC-PMMA integrates better with bone than the UC-PMMA, and all goats recovered after surgery without nerve damage. After 3 and 6 months, the implants were stable. New trabecular bone was observed in the TC-AB group. In the UC-PMMA group a thick fibrous capsule had formed around the implants. The MC-PMMA was observed to have perfect osteogenesis and bone ingrowth to adjacent bone surface. Minimally invasive injectable lumbar interbody fusion using MC-PMMA bone cement was shown to have profound clinical value, and the MC-PMMA showed potential application prospects.


Assuntos
Cimentos Ósseos/química , Colágeno/química , Polimetil Metacrilato/química , Fusão Vertebral/métodos , Animais , Materiais Biocompatíveis/química , Cabras , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Modelos Animais , Parafusos Pediculares , Titânio/química , Tomografia Computadorizada Espiral , Microtomografia por Raio-X
20.
Therap Adv Gastroenterol ; 13: 1756284820909172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215053

RESUMO

BACKGROUND: Endoscopic resection cap technique (ER-Cap), multiband mucosectomy (MBM), and endoscopic submucosal dissection (ESD) have been widely applied in the treatment of esophageal squamous neoplasia and cancer. However, little is known with regards to the comparison of these methods. This study aimed to compare the feasibility, safety, effectiveness, and costs of these three techniques. METHODS: A retrospective analysis of patients with squamous premalignant or early malignant lesions of the esophagus undergoing ER-Cap, MBM, or ESD from January 2009 to December 2015 in one of the centers in China was performed. The procedural data and follow-up data for all patients were recorded. RESULTS: A total of 672 patients with 733 lesions were included; 148 lesions (133 patients) were treated with ER-Cap, 427 lesions (388 patients) with MBM, and 158 lesions (151 patients) with ESD. The mean age was 61.59 years and the male-to-female ratio was 2.78:1. The operation time was significantly shorter for ER-Cap (29.26 ± 16.73 mins, p < 0.001) group, and the hospitalization costs were significantly lower in the MBM group (20,942.03 ± 8435.56ï¿¥, p = 0.003). The resection sample size of ESD was significantly larger (4.40 ± 1.20 cm, p < 0.001) and the en bloc resection rate of ESD was significantly higher (p < 0.001) than that of the other two groups. The frequencies of perforation, bleeding, and cicatricial stenosis were significantly lower in the MBM group (p < 0.001, p = 0.011, p = 0.009). Three local recurrences were observed in the ER-Cap group, while no recurrence was observed in MBM and ESD groups. There were three and two metastatic patients observed in the MBM and ESD groups, respectively. CONCLUSIONS: ER-Cap, MBM, and ESD are all minimally invasive, safe, and effective methods for treating early esophageal squamous cell carcinoma. MBM could be considered as a good alternative when performed by a less-experienced endoscopist in high-incidence areas with limited resources.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA