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1.
Environ Technol ; : 1-25, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236009

RESUMO

In the process of exploitation, transportation and refining of high-sulfur crude oil, a large number of oil sludge (OS) with high sulfur content is produced. Pyrolysis has been proved to be an effective method for OS disposal, but for solid waste with high sulfur content, lots of sulfur-containing gases will be released during thermal disposal. The addition of calcium oxide [1] in pyrolysis process is an economical and effective way to capture sulfur-containing gases. In order to understand the pyrolysis process of OS with CaO, a thermogravimetric analyzer was used to conduct pyrolysis experiments of OS with different Ca/S molar ratios (0, 1, 2, and 3) at different heating rates (10, 20, 30 and 40 °C/min). The results showed that with the increase of CaO addition the derivative thermogravimetric curves (DTG curves) showed a gentle trend. In addition, new weight loss peaks were occurred at 700∼900°C and after 1100°C, which were the decomposition of calcium carbonate and calcium sulfate, respectively. The kinetic parameters were solved by Friedman, FWO, and Starink methods, and the results were similar, with an average activation energies (E) value of 214 kJ/mol. The change trend of the activation energy followed by an increase and then a decrease corresponding to the change of energy demand for the reaction. The calculated average values of ΔH, ΔG and ΔS were about 207 kJ/mol, 447 kJ/mol and -0.3250 kJ/mol respectively. When the conversion rate was 0.5, the thermodynamic parameters reached their maximum values.

2.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207256

RESUMO

ATP-binding cassette (ABC) transporter proteins are a gene super-family in plants and play vital roles in growth, development, and response to abiotic and biotic stresses. The ABC transporters have been identified in crop plants such as rice and buckwheat, but little is known about them in soybean. Soybean is an important oil crop and is one of the five major crops in the world. In this study, 255 ABC genes that putatively encode ABC transporters were identified from soybean through bioinformatics and then categorized into eight subfamilies, including 7 ABCAs, 52 ABCBs, 48 ABCCs, 5 ABCDs, 1 ABCEs, 10 ABCFs, 111 ABCGs, and 21 ABCIs. Their phylogenetic relationships, gene structure, and gene expression profiles were characterized. Segmental duplication was the main reason for the expansion of the GmABC genes. Ka/Ks analysis suggested that intense purifying selection was accompanied by the evolution of GmABC genes. The genome-wide collinearity of soybean with other species showed that GmABCs were relatively conserved and that collinear ABCs between species may have originated from the same ancestor. Gene expression analysis of GmABCs revealed the distinct expression pattern in different tissues and diverse developmental stages. The candidate genes GmABCB23, GmABCB25, GmABCB48, GmABCB52, GmABCI1, GmABCI5, and GmABCI13 were responsive to Al toxicity. This work on the GmABC gene family provides useful information for future studies on ABC transporters in soybean and potential targets for the cultivation of new germplasm resources of aluminum-tolerant soybean.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Alumínio/toxicidade , Proteínas de Plantas/metabolismo , Soja/genética , Transportadores de Cassetes de Ligação de ATP/genética , Resistência a Medicamentos/genética , Proteínas de Plantas/genética , Soja/efeitos dos fármacos , Soja/metabolismo
3.
Nat Commun ; 12(1): 4089, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215733

RESUMO

Pediatric high-grade glioma (pHGG) is a major contributor to cancer-related death in children. In vitro and in vivo disease models reflecting the intimate connection between developmental context and pathogenesis of pHGG are essential to advance understanding and identify therapeutic vulnerabilities. Here we report establishment of 21 patient-derived pHGG orthotopic xenograft (PDOX) models and eight matched cell lines from diverse groups of pHGG. These models recapitulate histopathology, DNA methylation signatures, mutations and gene expression patterns of the patient tumors from which they were derived, and include rare subgroups not well-represented by existing models. We deploy 16 new and existing cell lines for high-throughput screening (HTS). In vitro HTS results predict variable in vivo response to PI3K/mTOR and MEK pathway inhibitors. These unique new models and an online interactive data portal for exploration of associated detailed molecular characterization and HTS chemical sensitivity data provide a rich resource for pediatric brain tumor research.

4.
Ann Palliat Med ; 10(6): 6351-6358, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34237958

RESUMO

BACKGROUND: To investigate the clinical values and relationships of bone turnover markers (BTMs), dual-energy X-ray absorptiometry (DXA), and quantitative computed tomodensitometry (QCT) in the screening of osteoporosis (OP) in elderly Chinese males. METHODS: General data, including age, height, and weight, the results of BTM measurements, and the findings of DXA and QCT in 357 male patients aged ≥50 years who visited the outpatient or inpatient Department of Geriatrics, Beijing Jishuitan Hospital from June 2017 to May 2019 were retrospectively analyzed. RESULTS: The OP detection rates based on T-scores of DXA L1-4, DXA total hip, and spine QCT were 3.4% (12/357), 13.2% (47/357), and 40.3% (144/357), respectively. QCT had a significantly higher OP detection rate than did DXA (P<0.001). There were 24 cases of fragility fractures, which were significantly correlated with the DXA total hip BMD and its T-score, with risk cut-off values of 0.607 g/cm2 and -2.950, respectively. The measured levels of the 5 BTMs were as follows: total procollagen type I amino-terminal propeptide (tPINP), 39.23±20.82 ng/mL; ß-isomerized C-terminal telopeptides (ß-CTX), 0.38±0.21 ng/mL; osteocalcin (OC), 13.50±8.80 ng/mL; 25-hydroxycholecalciferol (25(OH)D3), 12.90±7.46 ng/mL; and parathormone (PTH), 54.50±25.35 pg/mL. The elevation of tPINP, ß-CTX, and OC were negatively correlated with aging and positively correlated with decreased BMD (all P<0.05). OC and 25(OH)D3 values were significantly lower than their normal range. Among the 43 patients with normal bone mass on both DXA and QCT examinations, 34 presented with abnormal BTMs, including elevated tPINP in 2 cases, elevated ß-CTX in 2 cases, and OC decreased in 31 cases. CONCLUSIONS: In the Chinese elderly male population, spine QCT has a higher detection rate of OP than DXA, whereas hip DXA is more advantageous in predicting the risk of fragility fracture. tPINP, ß-CTX, and OC can be used as reliable indicators for the dynamic observation of bone content changes and may screen for early bone metabolism abnormalities when BMD examinations still show negative results.


Assuntos
Densidade Óssea , Remodelação Óssea , Absorciometria de Fóton , Idoso , China , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Food Funct ; 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34251375

RESUMO

In this study, the immunomodulatory effect of sea buckthorn (SBT) pulp oil was elucidated in immunosuppressed Balb/c mice induced by cyclophosphamide (CTX). The results showed that SBT pulp oil could reverse the decreasing trend of body weight, thymus/spleen index and hematological parameters induced by CTX. Compared with immunosuppressive mice induced by CTX, SBT pulp oil could enhance NK cytotoxicity, macrophage phagocytosis, and T lymphocyte proliferation, and regulate the proportion of T cell subsets in mesenteric lymph nodes (MLN), and promote the production of secretory immunoglobulin A (sIgA), IFN-γ, IL-2, IL-4, IL-12 and TNF-α in the intestines. In addition, SBT pulp oil can promote the production of short fatty acids (SCFAs), increase the diversity of gut microbiota, improve the composition of intestinal flora, increase the abundance of Alistipes, Bacteroides, Anaerotruncus, Lactobacillus, ASF356, and Roseburia, while decreasing the abundance of Mucispirillum, Anaeroplasma, Pelagibacterium, Brevundimonas, Ochrobactrum, Acinetobacter, Ruminiclostridium, Blautia, Ruminiclostridium, Oscillibacter, and Faecalibaculum. This study shows that SBT pulp oil can regulate the diversity and composition of intestinal microflora in CTX-induced immunosuppressive Balb/c mice, thus enhancing the intestinal mucosa and systemic immune response. The results can provide a basis for understanding the function of SBT pulp oil and its application as a new probiotic and immunomodulator.

6.
J Int Med Res ; 49(7): 3000605211031430, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34282642

RESUMO

Pyriform sinus fistula is uncommon and easily misdiagnosed. Most reported cases occur in children and are associated with either acute suppurative thyroiditis or deep neck infection. Asymptomatic pyriform sinus fistula is difficult to diagnose because it can manifest as an incidental thyroid nodule with highly suspicious malignant features on ultrasonography. The patient was a 41-year-old man with asymptomatic thyroid nodules incidentally detected on ultrasonography. Surgery was performed under the suspicion of thyroid cancer. Pathology findings revealed multiple cystic walls lined by ciliated columnar cells with stratified squamous epithelial cysts in a background of inflammatory and lymphoid cells. Barium swallow examination performed 2 weeks later revealed a sinus tract measuring 1.8 cm that arose from the apex of the left pyriform sinus. The diagnosis and management of pyriform sinus anomalies are challenging. The majority of physicians, including some otolaryngologists, lack an understanding of the disease, which should be considered one of the important differential diagnoses of neck masses. Barium swallow examination, ultrasonography, computed tomography, and laryngoscopy are useful to diagnose this condition.

7.
Magn Reson Chem ; 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34212405

RESUMO

The local structural, electronic, optical, and electron paramagnetic resonance (EPR) properties are uniformly studied for Cu2+ -doped rutile (TiO2 ) crystals by using the density functional theory (DFT) calculations. The local cation-oxygen bond lengths and planar bond angle, band gap, Mulliken charge and overlapping population, density of state (DOS), and UV-Vis absorption spectra are calculated for pure and copper-doped rutile. The smaller overlapping population of Cu-O bonds in the doped system than Ti-O bonds in pure rutile reflects weaker orbital admixtures or covalency of the former. Compared with pure rutile, Cu2+ doping leads to significant redshift of the UV-Vis absorption band and the narrow impurity band in visible and near-infrared regions arising from the Cu2+ d-d transitions and narrowing of the band gap by about 0.636 eV, possibly suggesting enhancement of visible light activity. The Cu dopant induces a spin magnetic moment of 0.74 µB for the doped rutile. The calculated UV-Vis absorption spectra and spin Hamiltonian parameters for copper-doped rutile show reasonable agreement with the experimental data and some improvement related to the previous perturbation formula calculations. Present systematic studies would be helpful to understand the mechanisms of the enhancement in the optical and magnetic properties of this material with transition-metal (especially Cu2+ ) dopants.

8.
Yi Chuan ; 43(6): 571-579, 2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284988

RESUMO

Long interspersed element-1 (LINE-1), which is the only autonomous retrotransposon in human genome, makes up about 17% of the human genome. For LINE-1 retrotransposition may result in genome instability, it was strictly restricted by organisms, and its expression was therefore barely detected in normal somatic cells. However, the expression of LINE-1 is a common phenomenon in most tumor or cancer tissues, suggesting a close relationship between LINE-1 expression and cancer development. Differentially expressed LINE-1 in cancer tissues can be used as a biomarker for tumor diagnosis and an important indicator of prognosis after cancer therapeutics. Meanwhile, the feasibility of LINE-1 as a potential drug target for tumor treatment has also been evaluating and verifying in clinicals. In this review, we introduce the application of LINE-1 as a biomarker in tumor diagnosis and prognostic, as well as the research progress in LINE-1 as potential drug target for tumor treatment, in order to provide some references for clinical application in cancer treatment.

9.
World Neurosurg ; 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34216836

RESUMO

OBJECTIVE: To review our use of pharmacologic provocative testing (PT) and intraoperative neurophysiologic monitoring (IONM) during endovascular embolization for eloquent arteriovenous malformations (AVMs), and better define their clinical utility. METHODS: This is a prospective study between June 1, 2018 and June 1, 2020. Prior to endovascular embolization, superselective PTs with propofol injection were performed. The PT results were assessed by IONM. The impact of different doses of propofol on PT results was compared. RESULTS: Under General anesthesia, 111 PTs and 48 endovascular embolizations were performed in 22 patients. For the initial 48 PTs before planned embolization, 38 PTs with 5 mg propofol were negative and repeat PTs with 7 mg propofol were also negative. For the remaining 10 positive PTs, the microcatheter tip was adjusted to an alternative site until repeat PTs were negative to assure a subsequent safe embolization. In comparison, 5-mg-propofol PT results were consistent with 7-mg-propofol PTs in larger-sized feeders while for smaller-sized vessels, 3-mg-propofol PT results were consistent with 5-mg-propofol PTs. The negative predictive value of PTs was 97.9% (47/48) as only one of the 48 embolizations with negative PTs resulted in postoperative hemorrhage and none of the other 47 embolizations led to a postoperative neurologic deficit. CONCLUSIONS: PTs and IONM are valuable techniques to predict neurological deficits and improve procedure decision making during AVM embolization under general anesthesia. A 5 mg dose of propofol may be sufficient for PTs in larger-sized feeders while a 3 mg dose may be sufficient in smaller-sized feeding branches.

10.
Se Pu ; 39(4): 424-429, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-34227763

RESUMO

Cervical cancer is the fourth most common cancer among women. Human papilloma virus (HPV) is the most common cause of cervical cancer which accounts for 5% of all human cancers and results in about 528000 cases and 266000 deaths every year. HPV vaccines are considered the most effective strategy for the prevention of HPV infection and cervical carcinoma. Since 2006, three prophylactic vaccines against HPV have been available on the market, including bivalent vaccines, quadrivalent vaccines, and nine-valent vaccines. Among them, nine-valent vaccines have been reported to be the most effective. They can prevent 97% of the high-grade pre-cancer lesions. Virus-like particles (VLPs), which are arranged as 360 copies of capsid proteins L1, are the only antigens of the HPV vaccine. Nine-valent HPV vaccines are prepared by mixing nine types of VLPs with adjuvants. Thus, the quality of the VLPs, including their stability and content in the HPV bulk, is very important for developing HPV vaccines. In this study, a method was developed for the determination of the nine types of VLPs (HPV6/11/16/18/31/33/45/52/58) in HPV bulk by size exclusion chromatography (SEC). The parameters of this method were optimized in terms of column brand, pore size of stationary phase particles, buffer concentration, and pH value. SHIMSEN Ankylo SEC-300 column (300 mm×7.8 mm, 3 µm) combined with a buffer aqueous solution containing 300 mmol/L NaCl and 50 mmol/L phosphate (pH 7.0) was utilized to separate the VLPs from the matrix since a narrow peak shape and good repeatability for VLPs could be obtained with this column and mobile phase. The optimized method had a wide linear range, good repeatability (RSDs of peak area were not more than 5.0%), and a satisfactory sensitivity (LOQs in the range of 4.58-15.24 µg/mL). The optimized method was used to determine the VLPs in the HPV bulk. The LOQs of the current method were much lower than the content of the nine types of VLPs in the HPV bulk, indicating that this method was sensitive enough for the determination of the nine types of VLPs in the HPV bulk. The method was also used to determine the VLPs in an HPV bulk that had been stored at 4 ℃ for one week. A decrease in the nine types of VLPs in the range of 10.0%-62.6% was observed after they were stored at 4 ℃ for one week. An HPV vaccine was prepared by mixing the VLPs with an adjuvant. Thereafter, the VLPs were adsorbed on the surface of the adjuvant. The developed method was applied to determine the free VLPs in twelve batches of HPV vaccines from three different manufacturers. No obvious free protein was detected in the twelve batches of the HPV vaccines from the three manufacturers, indicating that VLPs from these manufactures react well with their aluminum adjuvant. Folin-phenol (Lowry assay) is commonly used for the determination of proteins in vaccines. It is based on the reduction of phosphomolybdotungstic mixed acid chromogen in the phosphomolybdotungstic reagent, which results in an absorbance maximum at 650 nm. The Lowry method was sensitive to interfering substances. Most interfering substances caused a lower color yield, while some detergents caused a slight increase in color. To reduce the effect of the interfering substances, a procedure for precipitating the proteins was usually required before the sample was tested. Thus, the Lowry assay is complex, time-consuming, and of low selectivity. Compared to the Lowry method, the method we developed is simpler and more automatic. It is a high-throughput method of determining VLPs. It can be used to determine VLPs in HPV bulk and free VLPs in HPV vaccines.

11.
J Control Release ; 336: 40-53, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34119557

RESUMO

It remains challenging to treat tumor metastasis currently in the light of multiple cascade processes of tumor metastasis. Additionally, multiple clinical drugs for metastasis have quite limited therapeutic potential and even facilitate metastasis in preclinical models. Thus, potential metastasis targets and novel metastasis-directed drugs are urgently needed to be further developed. Herein, transforming growth factor-ß (TGF-ß) is verified to contribute to lung metastasis in a context-dependent manner in the 4T1 orthotopic tumor-bearing mice model, which induces epithelial-mesenchymal-transition (EMT) to promote tumor dissemination from the primary site and dampens the anti-tumor response of neutrophils to support tumor colonization at the metastatic niche. In view of neutrophils' superior tropism towards both inflammatory primary tumor and metastatic niche, SB525334, a TGF-ß receptor inhibitor, is loaded into cationic liposome (SBLP) which is subsequently incorporated into neutrophils to yield the cyto-pharmaceuticals (SBLP/NE). The systemically infused SBLP/NE can simultaneously migrate into both primary and metastatic sites, then release SB525334 in response to tumor stimuli, and contextually inhibit TGF-ß-mediated-EMT and phenotype reversal of infiltrated neutrophils, showing substantial metastasis suppression efficacy without causing any detectable toxicities. This project shifts the paradigm for metastasis suppression therapy by simultaneous blockage of contextual TGF-ß using metastatic-cascades-targeting neutrophil cyto-pharmaceuticals.

12.
Oxid Med Cell Longev ; 2021: 5587340, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093959

RESUMO

Diabetic retinopathy (DR) is a kind of severe retinal neurodegeneration. The advanced glycation end products (AGEs) affect autophagy, and mitochondrial function is involved in DR. Adenosine-activated protein kinase (AMPK) is an important metabolic sensor that can regulate energy homeostasis in cells. However, the effect of AMPK in DR is still not fully understood. In this study, we investigated the effect of AMPK on diabetes-induced photoreceptor cell degeneration. In vivo, a diabetic mouse model was established by streptozotocin (STZ) injection. Haematoxylin-eosin (HE) staining was used to observe retinal morphology and measure the thicknesses of different layers in the retina. Electroretinogram (ERG) was used to evaluate retinal function. In vitro, 661w cells were treated with AGEs with/without an AMPK agonist (metformin) or AMPK inhibitor (compound C). Flow cytometry and CCK-8 assays were used to analyse apoptosis. Mitochondrial membrane potential was analysed by JC-1. Western blotting and qRT-PCR were used to examine the expression of related proteins and genes, respectively. The wave amplitude and the thickness of the outer nuclear layer were decreased in diabetic mice. The expression of rhodopsin and opsin was also decreased in diabetic mice. In vitro, the percentage of apoptotic cells was increased, the expression of the apoptosis-related protein Bax was increased, and Bcl-2 was decreased after AGE treatment in 661w cells. The expression of the autophagy-related protein LC3 was decreased, and p62 was increased. The mitochondrial-related gene expression and membrane potential were decreased, and mitochondrial morphology was abnormal, as observed by TEM. However, AMPK stimulation ameliorated this effect. These results indicate that AMPK stimulation can delay diabetes-induced photoreceptor degeneration by regulating autophagy and mitochondrial function.

13.
J Toxicol Sci ; 46(6): 255-262, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34078832

RESUMO

Fasudil is an inhibitor of Rhoa/ROCK signaling, which is involved in anti-inflammatory and anti-injury effects. The purpose of this study was to explore the effects of Fasudil on acetaminophen (APAP)-induced liver injury and reveal its potential molecular mechanism. In this study, C57BL/6 J mice were divided into different groups and treated with APAP and specified dose of Fasudil. HE staining was used to detect the changes of liver pathological tissues induced by APAP. ELISA assay was performed to detected the level of related factors. Western blot was used to detect the expressions of Rhoa, ROCK1, ROCK2. CD86 and CD6 were determined by RT-PCR and immunohistochemical staining detected the difference in CD86 expression. Rhoa/ROCK expression was increased in APAP-induced liver injury, and Fasudil targeted the expression of Rhoa/ROCK. Fasudil inhibits APAP-induced hepatic pathological changes and liver function injury. Fasudil inhibits the release of APAP-induced systemic inflammatory factors in liver tissue. Fasudil inhibits the activity of antioxidant enzymes, lipid peroxidation and macrophage infiltration induced by APAP in liver tissues. Fasudil alleviates APAP-induced liver injury via targeting Rhoa/ROCK signal pathway, indicating the possibility for clinical use of Fasudil in APAP-induced liver injury.

14.
Int J Cancer ; 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34109624

RESUMO

The purpose of our study was to investigate the safety, pharmacokinetics (PK), and initial antitumor efficacy of HC-1119 in patients with metastatic castration-resistant prostate cancer (mCRPC). Eligible mCRPC patients were included in our study (NCT03774056) with two parts. Part A was a dose escalation study in which patients received a dose escalation of HC-1119 (40, 80, 160 and 200 mg/day). Part B was a dose expansion study in which patients received HC-1119 at the dose of 80 and 160 mg. Safety assessment and pharmacokinetic samplings were performed for all patients at the given time points; preliminary tumor response was also assessed. Twenty-four patients were enrolled in part A and 19 patients in part B, respectively. HC-1119 was safe, well tolerated and no dose-limiting toxicity was observed. Fatigue was the most common treatment-related adverse event and no seizures were observed. At the dose levels of 40, 80 and 160 mg, the AUC and Cmax of HC-1119 in plasma increased almost dose-proportionally at the steady state in mCRPC patients. Maximum prostate-specific antigen (PSA) response rates (≥50% reduction from the baseline) in dose escalation and dose expansion cohorts were 77% and 75%, respectively; the overall disease control rate (22 patients available for imaging analysis) was 72.7%, with PR in 4 patients, SD in 12 patients and PD in 6 patients; the 2-year overall survival rate in patients from Part B was 56.8%. HC-1119 was safe, well tolerated and efficacious and HC-1119 at 80 mg/day is recommended for further studies.

15.
J Sep Sci ; 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34185396

RESUMO

An open tubular capillary electrochromatography column was prepared by immobilizing ß-cyclodextrin on the inner wall of pretreated capillary via noncovalent adsorption of polydopamine. The resulting coating layer on the capillary was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Electroosmotic flow was studied to evaluate the variation of the immobilized columns. The prepared columns showed good chiral separation performance toward five proton pump inhibitors including lansoprazole, pantoprazole, tenatoprazole, rabeprazole, and omeprazole. The influences of ß-cyclodextrin concentration, coating time, buffer pH, buffer concentration, and applied voltage on separation were investigated. In the optimum conditions, the enantiomers of five analytes were fully resolved within 15 min with high resolutions of 4.57 to 8.13. The method was extensively validated in terms of accuracy, precision, and linearity and proved to be robust. The relative standard deviation values for migration times and peak areas of the analytes representing intraday and interday were less than 1.9 and 3.6%, respectively. Further, the polydopamine/ß-cyclodextrin coated capillary column could be successively used over 100 runs without showing significant decrease in the separation efficiency.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34065938

RESUMO

Chitosan-stabilized nano zero-valent iron (CTS-nZVI) prepared by the liquid-phase reduction method has been shown to achieve a good dispersion effect. However, there has been little analysis on the mechanism affecting its stability and transport in saturated porous media. In this paper, settling experiments were conducted to study the stabilization of CTS-nZVI. The transport of CTS-nZVI in saturated porous media at different influencing factors was studied by sand column experiments. The stability mechanism of CTS-nZVI was analyzed from the point of view of colloidal stability by settling experiments and a zeta potential test. The theoretical model of colloidal filtration was applied for the calculation of transport coefficients on the basis of the column experiments data. Considering attachment-detachment effects, a particle transport model was built using HYDRUS-1D software to analyze the transport and spatial distribution of CTS-nZVI in a sand column.


Assuntos
Quitosana , Nanopartículas Metálicas , Ferro , Tamanho da Partícula , Porosidade , Dióxido de Silício
17.
Front Immunol ; 12: 687296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177939

RESUMO

Background: Targeting immune checkpoints for HIV treatment potentially provides a double benefit resulting from the ability to restore viral-specific CD8+ T-cell functions and enhance HIV production from reservoir cells. Despite promising pre-clinical data, PD-1 blockade alone in HIV-1-infected patients with advanced cancer has shown limited benefits in controlling HIV, suggesting the need for additional targets beyond PD-1. CD39 and PD-1 are highly co-expressed on CD8+ T cells in HIV-1 infection. However, the characteristics of CD39 and PD-1 dual-positive CD8+ T-cell subsets in chronic HIV-1 infection remain poorly understood. Methods: This study enrolled 72 HIV-1-infected patients, including 40 treatment naïve and 32 ART patients. A total of 11 healthy individuals were included as controls. Different subsets of CD8+ T cells defined by CD39 and/or PD-1 expression were studied by flow cytometry. The relationships between the frequencies of the different subsets and parameters indicating HIV-1 disease progression were analyzed. Functional (i.e., cytokine secretion, viral inhibition) assays were performed to evaluate the impact of the blockade of adenosine and/or PD-1 signaling on CD8+ T cells. Results: The proportions of PD-1+, CD39+, and PD-1+CD39+ CD8+ T cells were significantly increased in treatment naïve patients but were partially lowered in patients on antiretroviral therapy. In treatment naïve patients, the proportions of PD-1+CD39+ CD8+ T cells were negatively correlated with CD4+ T-cell counts and the CD4/CD8 ratio, and were positively correlated with viral load. CD39+CD8+ T cells expressed high levels of the A2A adenosine receptor and were more sensitive to 2-chloroadenosine-mediated functional inhibition than their CD39- counterparts. In vitro, a combination of blocking CD39/adenosine and PD-1 signaling showed a synergic effect in restoring CD8+ T-cell function, as evidenced by enhanced abilities to secrete functional cytokines and to kill autologous reservoir cells. Conclusion: In patients with chronic HIV-1 infection there are increased frequencies of PD-1+, CD39+, and PD-1+CD39+ CD8+ T cells. In treatment naïve patients, the frequencies of PD-1+CD39+ CD8+ T cells are negatively correlated with CD4+ T-cell counts and the CD4/CD8 ratio and positively correlated with viral load. Combined blockade of CD39/adenosine and PD-1 signaling in vitro may exert a synergistic effect in restoring CD8+ T-cell function in HIV-1-infected patients.

18.
Parasit Vectors ; 14(1): 283, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039408

RESUMO

BACKGROUND: The proliferative stage (tachyzoite) of Toxoplasma gondii (T. gondii) is critical for its transmission and pathogenesis, and a proto-oncogene eukaryotic translation initiation factor (eIF-5A) plays an important role in various cellular processes such as cell multiplication. METHODS: We performed a proteomic study to evaluate the specific roles of eIF-5A involved in invasion and replication of T. gondii, and both in vivo and in vitro trials using eIF-5A-interfered and wild tachyzoites were performed to verify the proteomic results. RESULTS: The results of our study showed that T. gondii eIF-5A affected tachyzoite growth and also participated in the synthesis of proteins through regulation of both ribosomal and splicing pathways. Inhibition of eIF-5A in T. gondii resulted in the downregulated expression of soluble adhesions, such as microneme protein 1 (MIC1) and MIC4, which in turn decreased the parasite population that adhered to the surface of host cells. The reduced attachment, combined with lower expression of some rhoptry proteins (ROPs) and dense granule antigens (GRAs) involved in different stages of T. gondii invasion such as ROP4 and GRA3, ultimately reduce the invasion efficiency. These processes regulated by eIF-5A eventually affect the replication of tachyzoites. CONCLUSIONS: Our findings showed that eIF-5A influenced tachyzoite survival and was also involved in the process of parasite invasion and replication. These results will provide new clues for further development of targeted drugs to control T. gondii infection.

19.
Pharmacol Res ; 169: 105682, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34019980

RESUMO

The neuroactive steroid allopregnanolone (ALLO) is an endogenous positive allosteric modulator of GABA type A receptor (GABAAR), and the down-regulation of its biosynthesis have been attributed to the development of mood disorders, such as depression, anxiety and post-traumatic stress disorder (PTSD). ALLO mediated depression/anxiety involves GABAergic mechanisms and appears to be related to brain-derived neurotrophic factor (BDNF), dopamine receptor, glutamate neurotransmission, and Ca2+ channel. In the clinical, brexanolone, as a newly developed intravenous ALLO preparation, has been approved for the treatment of postpartum depression (PPD). In addition, traditional antidepressants such as selective serotonin reuptake inhibitor (SSRI) could reverse ALLO decline. Recently, the translocation protein (TSPO, 18 kDa), which involves in the speed-limiting step of ALLO synthesis, and ALLO derivatization have been identified as new directions for antidepressant therapy. This review provides an overview of ALLO researches in animal model and patients, discusses its role in the development and treatment of depression/anxiety, and directs its therapeutic potential in future.

20.
Chemistry ; 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33998733

RESUMO

Highly selective one-step hydrogenation of phenol to cyclohexanone, an important intermediate in the production of nylon 6 and nylon 66, is desirable but remains a challenge. Pd nanoparticles supported on nitrogen- and oxygen-functionalized carbon nanotubes (NCNTs, OCNTs) were prepared, characterized, and applied in the hydrogenation of phenol to cyclohexanone to study the effect of N-doping. Almost full conversion of phenol with high selectivity to cyclohexanone was achieved over Pd/NCNT under mild reaction conditions using either H2 or formic acid (FA) as a hydrogen source. The effects of reaction temperature and FA/phenol ratio and the reusability were investigated. Separate FA decomposition experiments without and with the addition of phenol were performed to investigate the reaction mechanism, especially the deactivation behavior. Deactivation was observed for both catalysts during the FA decomposition, while only Pd/OCNT rather than Pd/NCNT was deactivated in the transfer hydrogenation with FA and the FA decomposition in the presence of phenol, indicating the unique role of N-doping. Therefore, we assume that deactivation is caused by the strongly bound formates on the active Pd sites, suppressing further FA decomposition and/or transfer hydrogenation on Pd. The nonplanar adsorption of phenol on NCNTs via weak O-H⋅⋅⋅N interactions enables the occurrence of the subsequent hydrogenation by adsorbed formate on Pd.

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