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1.
Mol Pharm ; 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39322604

ABSTRACT

B7-H3 has emerged as a promising target and potential biomarker for diagnosing tumors, evaluating treatment efficacy, and determining patient prognosis. Hu4G4 is a recombinant humanized antibody that selectively targets the extracellular domain of human B7-H3. In this study, we describe the radiolabeling of hu4G4 with the positron emission tomography (PET) emitter radionuclide zirconium 89 (89Zr) and evaluate its potency as an immuno-PET tracer for B7-H3-targeted imaging by comparing it in vitro and in vivo to [89Zr]Zr-DFO-DS-5573a using various models. The radiolabeled compound, [89Zr]Zr-desferrioxamine-hu4G4 ([89Zr]Zr-DFO-hu4G4), demonstrated a high radiochemical purity (RCP) of greater than 99% and a specific activity of 74 MBq/mg following purification. Additionally, it maintained stability in human serum albumin (HSA) and acetate buffer, preserving over 90% of its RCP after 7 days. Three cell lines targeting human B7-H3(U87/CT26-CD276/GL261-CD276) were used. Flow cytometry analysis indicated that the B7-H3-positive cells (U87/CT26-CD276/GL261-CD276) had a higher B7-H3 protein level with no expression in the B7-H3-negative cells (CT26-wt/GL261-wt) (P < 0.001). Moreover, the cellular uptake was 45.71 ± 3.78% for [89Zr]Zr-DFO-hu4G4 in CT26-CD276 cells versus only 0.93 ± 0.47% in CT26-wt cells and 30.26 ± 0.70% when [89Zr]Zr-DFO-hu4G4 in CT26-CD276 cells were blocked with 100× 8H9. The cellular uptake of [89Zr]Zr-DFO-hu4G4 was akin to that observed with [89Zr]Zr-DFO-DS-5573a with no significant differences (45.71 ± 3.78 % vs 47.07 ± 0.86 %) in CT26-CD276 cells. Similarly, the CT26-CD276 mouse model demonstrated markedly low organ uptake and elevated tumor uptake 48 h after [89Zr]Zr-DFO-hu4G4 injection. PET/CT analysis showed that the tumor-to-muscle (T/M) ratios were substantially higher compared to other imaging groups: 27.65 ± 3.17 in CT26-CD276 mice versus 11.68 ± 4.19 in CT26-wt mice (P < 0.001) and 16.40 ± 0.78 when 100× 8H9 was used to block [89Zr]Zr-DFO-hu4G4 in CT26-CD276 mice (P < 0.01) at 48 h post-injection. Additionally, the tracer showed markedly high accumulation in the tumor region (22.57 ± 3.03% ID/g), comparable to the uptake of [89Zr]Zr-DFO-DS-5573a (24.76 ± 5.36% ID/g). A dosimetry estimation study revealed that the effective dose for [89Zr]Zr-DFO-hu4G4 was 2.96 × 10-01 mSv/MBq, which falls within the acceptable range for further research in nuclear medicine. Collectively, these results indicated that [89Zr]Zr-DFO-hu4G4 was successfully fabricated and applied in B7-H3-targeted tumor PET/CT imaging, which showed excellent imaging quality and tumor detection efficacy in tumor-bearing mice. It is a promising imaging agent for identifying tumors that overexpress B7-H3 for future clinical applications.

2.
Adv Sci (Weinh) ; : e2408374, 2024 Sep 26.
Article in English | MEDLINE | ID: mdl-39324659

ABSTRACT

Due to its inherent ductility, Ag2S shows promise as a flexible thermoelectric material for harnessing waste heat from diverse sources. However, its thermoelectric performance remains subpar, and existing enhancement strategies often compromise its ductility. In this study, a novel Sn-doping-induced biphasic structuring approach is introduced to synergistically control electron and phonon transport. Specifically, Sn-doping is incorporated into Ag2S0.7Se0.3 to form a biphasic composition comprising (Ag, Sn)2S0.7Se0.3 as the primary phase and Ag2S0.7Se0.3 as the secondary phase. This biphasic configuration achieves a competitive figure-of-merit ZT of 0.42 at 343 K while retaining exceptional ductility, exceeding 90%. The dominant (Ag, Sn)2S0.7Se0.3 phase bolsters the initially low carrier concentration, with interfacial boundaries between the phases effectively mitigating carrier scattering and promoting carrier mobility. Consequently, the optimized power factor reaches 5 µW cm-1 K-2 at 343 K. Additionally, the formation of the biphasic structure induces diverse micro/nano defects, suppressing lattice thermal conductivity to a commendable 0.18 W m-1 K-1, thereby achieving optimized thermoelectric performance. As a result, a four-leg in-plane flexible thermoelectric device is fabricated, exhibiting a maximum power density of ≈49 µW cm-2 under the temperature difference of 30 K, much higher than that of organic-based flexible thermoelectric devices.

3.
Adv Healthc Mater ; : e2401685, 2024 Aug 24.
Article in English | MEDLINE | ID: mdl-39180453

ABSTRACT

In the realm of combating acute lung injury (ALI) induced by a myriad of triggers including sepsis, pneumonia, aspiration, trauma, and pancreatitis, macrophages emerge as crucial players. However, traditional treatments such as systemic administration of glucocorticoids come with the baggage of severe side effects, curtailing their utility. Enter an innovative solution: a biomimetic drug delivery system fashioned from cryo-shocked macrophages, tailored for pulmonary drug delivery. Positron emission tomography (PET) imaging has shed light on the remarkable targeting abilities of live M1 macrophages, showcasing their unparalleled efficacy in homing in on local inflammatory foci when contrasted with naive, M1, and M2 macrophages. Building upon this foundation, liquid nitrogen-treated (LNT) M1 macrophages are developed, engineered to preserve their inflammation-targeting prowess while sidestepping the release of pro-inflammatory cytokines. This breakthrough allows for the delivery of glucocorticoids directly to inflamed lung tissues, efficiently quelling inflammation and mitigating pulmonary edema while drastically reducing systemic drug exposure. Inspired by the effectiveness of live M1 macrophages, the potential of glucocorticoid-loaded LNT M1 macrophages are harnessed, utilizing them as a stealthy "Trojan horse" in the battle against pneumonia-induced ALI. This innovative approach holds promise as a safe and potent treatment avenue for acute lung injury.

4.
Drug Des Devel Ther ; 18: 3659-3666, 2024.
Article in English | MEDLINE | ID: mdl-39185080

ABSTRACT

Objective: This randomized, double-blind, placebo-controlled trial aimed to evaluate the efficacy of tranexamic acid essence combined with iontophoresis in treating melasma. Methods: Thirty participants were recruited and randomly assigned to the experimental (Group A) or control group (Group B). Group A received tranexamic acid essence iontophoresis treatment twice weekly for three months, while Group B received placebo treatment. Melasma Area and Severity Index (MASI) scores and skin luminance (L) values were assessed at baseline and weeks 4, 8, and 12. Results: No significant differences in baseline characteristics were observed between the groups. The mean MASI score reduction rate was significantly higher in Group A (-0.10±0.12%) compared to Group B (-0.02±0.09%) (p<0.05). Skin L values significantly increased in Group A from 61.32±3.53 to 63.32±1.78, while slightly decreasing in Group B (p=0.037). Conclusion: Tranexamic acid essence combined with iontophoresis significantly improved MASI scores and skin luminance compared to placebo, demonstrating its effectiveness in treating melasma. Further research with larger sample sizes and longer follow-up is warranted to validate long-term effects and recurrence rates.


Subject(s)
Iontophoresis , Melanosis , Tranexamic Acid , Humans , Tranexamic Acid/administration & dosage , Tranexamic Acid/therapeutic use , Melanosis/drug therapy , Double-Blind Method , Female , Adult , Middle Aged , Male , Young Adult , Treatment Outcome
5.
Environ Geochem Health ; 46(9): 312, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39001963

ABSTRACT

The ground cracks resulting from coal mining activities induce alterations in the physical and chemical characteristics of soil. However, limited knowledge exists regarding the impact of subsidence caused by coal mining on the distribution of potentially toxic elements (PTEs) fractions in farmland soil. In this study, we collected 19 soil profiles at varying depths from the soil surface and at horizontal distances of 0, 1, 2, and 5 m from the vertical crack. Using BCR extraction fractionation, we determined the geochemical fractions and total concentrations of Chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) to investigate their ecological risk, spatial fraction distribution, and main influencing factors. Results showed that the E r i values of Cd appearing in 68.7% of the samples were higher than 40 and less than 80, presented a moderate ecological risk. Chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), and lead (Pb) were mainly bound to residual fractions (> 60%) with lower mobility and Cd was dominated by F1 (acid-soluble fractions, 50%) and F2 (reducible fractions, 29%) in surface soil (0-20 cm). The geochemical fractionation revealed that the mobile fractions (F1-acid-soluble and F2-reducible) of PTEs were primarily located near the crack, influenced by available potassium. In contrast, the less mobile fractions (F3-oxidizable and F4-residual) exhibited higher concentrations at distances of 2 and 5 m from the crack, except for arsenic, influenced by the presence of clay particles and available phosphorus.


Subject(s)
Coal Mining , Environmental Monitoring , Metals, Heavy , Soil Pollutants , Soil Pollutants/analysis , Soil Pollutants/toxicity , Metals, Heavy/analysis , Metals, Heavy/toxicity , Soil/chemistry , Farms , Risk Assessment
6.
Sci Total Environ ; 949: 174980, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39053545

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) widely present in the environment, but their effect on cerebrovascular development has been rarely reported. In this study, dechorionated zebrafish embryos at 24 hpf were exposed to benzo(a)pyrene (BaP) at 0.5, 5 and 50 nM for 48 h, cerebrovascular density showed a significant reduction in the 5 and 50 nM groups. The expression of aryl hydrocarbon receptor (AhR) was significantly increased. Transcriptomic analysis showed that the pathway of positive regulation of vascular development was down-regulated and the pathway of inflammation response was up-regulated. The transcription of main genes related to vascular development, such as vegf, bmper, cdh5, f3b, itgb1 and prkd1, was down-regulated. Addition of AhR-specific inhibitor CH233191 in the 50 nM BaP group rescued cerebrovascular developmental defects and down-regulation of relative genes, suggesting that BaP-induced cerebrovascular defects was AhR-dependent. The cerebrovascular defects were persistent into adult fish raised in clean water, showing that the relative area of vascular network, the length of vessels per unit area and the number of vascular junctions per unit area were significantly decreased in the 50 nM group. Supplementation of berberine (BBR), a naturally derived medicine from a Chinese medicinal herb, alleviated BaP-induced cerebrovascular defects, accompanied by the restoration of altered expression of AhR and relative genes, which might be due to that BBR promoted BaP elimination via enhancing detoxification enzyme activities, suggesting that BBR could be a potential agent in the prevention of cerebrovascular developmental defects caused by PAHs.


Subject(s)
Benzo(a)pyrene , Berberine , Water Pollutants, Chemical , Zebrafish , Animals , Benzo(a)pyrene/toxicity , Water Pollutants, Chemical/toxicity , Berberine/pharmacology , Embryo, Nonmammalian/drug effects , Receptors, Aryl Hydrocarbon/metabolism , Polycyclic Aromatic Hydrocarbons/toxicity
7.
J Inflamm Res ; 17: 3419-3422, 2024.
Article in English | MEDLINE | ID: mdl-38828051

ABSTRACT

The increasing popularity of tattoo art, including facial cosmetic tattoos, has led to a growing societal acceptance of tattoos. However, complications such as lip inflammation following cosmetic lip tattoos remain a concern. This article presents the case of a 47-year-old Asian woman who experienced recurrent lip swelling, purulent discharge, and scarring after receiving lip tattoos. Despite previous treatment with corticosteroid injections yielding unsatisfactory results, the patient showed significant improvement with topical application of 2% Crisaborole, a phosphodiesterase-4 inhibitor. Crisaborole modulates intracellular cyclic adenosine monophosphate levels, thereby reducing tissue inflammation and swelling associated with chronic cheilitis. Additionally, pulse laser therapy was effective in addressing residual tattoo pigment and scar tissue. This case highlights the therapeutic challenges of managing chronic inflammatory diseases of the lips secondary to cosmetic tattoos and introduces Crisaborole as a promising treatment option, offering insights for managing similar conditions in the future.

8.
Sci China Life Sci ; 67(7): 1441-1454, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38561484

ABSTRACT

The basic mechanism of heterosis has not been systematically and completely characterized. In previous studies, we obtained three economically important fishes that exhibit rapid growth, WR (WCC ♀ × RCC ♂), WR-II (WR ♀ × WCC ♂), and WR-III (WR-II ♀ × 4nAU ♂), through distant hybridization. However, the mechanism underlying this rapid growth remains unclear. In this study, we found that WR, WR-II, and WR-III showed muscle hypertrophy and higher muscle protein and fat contents compared with their parent species (RCC and WCC). Candidate genes responsible for this rapid growth were then obtained through an analysis of 12 muscle transcriptomes. Notably, the mRNA level of mstnb (myostatin b), which is a negative regulator of myogenesis, was significantly reduced in WR, WR-II, and WR-III compared with the parent species. To verify the function of mstnb, a mstnb-deficient mutant RCC line was generated using the CRISPR-Cas9 technique. The average body weight of mstnb-deficient RCC at 12 months of age was significantly increased by 29.57% compared with that in wild-type siblings. Moreover, the area and number of muscle fibers were significantly increased in mstnb-deficient RCC, indicating hypertrophy and hyperplasia. Furthermore, the muscle protein and fat contents were significantly increased in mstnb-deficient RCC. The molecular regulatory mechanism of mstnb was then revealed by transcription profiling, which showed that genes related to myogenesis (myod, myog, and myf5), protein synthesis (PI3K-AKT-mTOR), and lipogenesis (pparγ and fabp3) were highly activated in hybrid fishes and mstnb-deficient RCC. This study revealed that low expression or deficiency of mstnb regulates somatic growth by promoting myogenesis, protein synthesis, and lipogenesis in hybrid fishes and mstnb-deficient RCC, which provides evidence for the molecular mechanism of heterosis via distant hybridization.


Subject(s)
Hybridization, Genetic , Muscle Development , Myostatin , Animals , Myostatin/genetics , Myostatin/metabolism , Muscle Development/genetics , Hybrid Vigor/genetics , Male , Fishes/genetics , Fishes/growth & development , Fishes/metabolism , Female , Transcriptome , Muscle Proteins/genetics , Muscle Proteins/metabolism , Muscle, Skeletal/metabolism , Muscle, Skeletal/growth & development , Fish Proteins/genetics , Fish Proteins/metabolism
9.
Nat Commun ; 15(1): 3426, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38654020

ABSTRACT

Single-walled carbon nanotubes (SWCNTs)-based thermoelectric materials, valued for their flexibility, lightweight, and cost-effectiveness, show promise for wearable thermoelectric devices. However, their thermoelectric performance requires significant enhancement for practical applications. To achieve this goal, in this work, we introduce rational "triple treatments" to improve the overall performance of flexible SWCNT-based films, achieving a high power factor of 20.29 µW cm-1 K-2 at room temperature. Ultrasonic dispersion enhances the conductivity, NaBH4 treatment reduces defects and enhances the Seebeck coefficient, and cold pressing significantly densifies the SWCNT films while preserving the high Seebeck coefficient. Also, bending tests confirm structural stability and exceptional flexibility, and a six-legged flexible device demonstrates a maximum power density of 2996 µW cm-2 at a 40 K temperature difference, showing great application potential. This advancement positions SWCNT films as promising flexible thermoelectric materials, providing insights into high-performance carbon-based thermoelectrics.

10.
J Cell Biol ; 223(4)2024 04 01.
Article in English | MEDLINE | ID: mdl-38466167

ABSTRACT

Focal adhesions (FAs) are transmembrane protein assemblies mediating cell-matrix connection. Although protein liquid-liquid phase separation (LLPS) has been tied to the organization and dynamics of FAs, the underlying mechanisms remain unclear. Here, we experimentally tune the LLPS of PXN/Paxillin, an essential scaffold protein of FAs, by utilizing a light-inducible Cry2 system in different cell types. In addition to nucleating FA components, light-triggered PXN LLPS potently activates integrin signaling and subsequently accelerates cell spreading. In contrast to the homotypic interaction-driven LLPS of PXN in vitro, PXN condensates in cells are associated with the plasma membrane and modulated by actomyosin contraction and client proteins of FAs. Interestingly, non-specific weak intermolecular interactions synergize with specific molecular interactions to mediate the multicomponent condensation of PXN and are efficient in promoting FA assembly and integrin signaling. Thus, our data establish an active role of the PXN phase transition into a condensed membrane-associated compartment in promoting the assembly/maturation of FAs.


Subject(s)
Focal Adhesions , Paxillin , Phase Separation , Humans , Actin Cytoskeleton , Focal Adhesions/metabolism , Integrins/metabolism , Paxillin/chemistry , Paxillin/metabolism
11.
Mol Biol Evol ; 41(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38421617

ABSTRACT

Polyploidy, a significant catalyst for speciation and evolutionary processes in both plant and animal kingdoms, has been recognized for a long time. However, the exact molecular mechanism that leads to polyploid formation, especially in vertebrates, is not fully understood. Our study aimed to elucidate this phenomenon using the zebrafish model. We successfully achieved an effective knockout of the cyclin N-terminal domain containing 1 (cntd1) using CRISPR/Cas9 technology. This resulted in impaired formation of meiotic crossovers, leading to cell-cycle arrest during meiotic metaphase and triggering apoptosis of spermatocytes in the testes. Despite these defects, the mutant (cntd1-/-) males were still able to produce a limited amount of sperm with normal ploidy and function. Interestingly, in the mutant females, it was the ploidy not the capacity of egg production that was altered. This resulted in the production of haploid, aneuploid, and unreduced gametes. This alteration enabled us to successfully obtain triploid and tetraploid zebrafish from cntd1-/- and cntd1-/-/- females, respectively. Furthermore, the tetraploid-heterozygous zebrafish produced reduced-diploid gametes and yielded all-triploid or all-tetraploid offspring when crossed with wild-type (WT) or tetraploid zebrafish, respectively. Collectively, our findings provide direct evidence supporting the crucial role of meiotic crossover defects in the process of polyploidization. This is particularly evident in the generation of unreduced eggs in fish and, potentially, other vertebrate species.


Subject(s)
Triploidy , Zebrafish , Male , Animals , Female , Tetraploidy , Seeds , Polyploidy , Ploidies
12.
Org Lett ; 26(7): 1432-1436, 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38350149

ABSTRACT

An interrupted N-heterocyclic carbene-catalyzed radical coupling strategy is disclosed for efficient alkylation and arylation of [60]fullerene. This novel and general strategy bridges the gap between organocatalytic radical cross-coupling and functionalization of fullerenes. Readily available feedstocks, remarkably broad substrate scope and functional group compatibility, and convenient late-stage nanomodification of complex molecules make this strategy with incomparable diversity and practicality in the synthesis of monoalkylated and -arylated fullerenes.

13.
J Am Chem Soc ; 146(2): 1681-1689, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38178655

ABSTRACT

The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of ∼492.8 cm3 V-1 s-1 W-1 K and a peak ZT of ∼0.4 at 473 K are achieved in Ge0.67Pb0.13Bi0.2Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.

15.
Pathol Int ; 74(3): 129-138, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38289121

ABSTRACT

Esophageal squamous cell carcinoma (ESCC) is a prevalent malignancy affecting the digestive tract, with an increasing incidence rate worldwide. Recently, numerous studies revealed that microRNAs were associated with gene expression regulation, particularly their involvement in the regulation of tumor cells, garnering widespread attention. Here, we discovered that miR-196a-5p was significantly upregulated in both ESCC tissues and cells, which was correlated with an unfavorable prognosis. Series functional in vitro investigations have confirmed that silencing miR-196a-5p obviously restrained the ESCC cells malignant phenotypes and promoted apoptosis. Bioinformatics analysis and rescue experiments revealed that miR-196a-5p directly targeted ITM2B, exerting influence on the development of ESCC cells through negative regulation of ITM2B expression. Xenograft mouse models were established for conducting in vivo experiments, providing further confirmation of the regulatory mechanism and biological significance of the miR-196a-5p/ITM2B axis in ESCC. Our research demonstrated miR-196a-5p promoted ESCC malignant progression by interacting with ITM2B, thereby providing novel clues and potential targets for the new diagnosis and thereby of ESCC.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , MicroRNAs , Animals , Humans , Mice , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Cell Line, Tumor , Cell Proliferation/genetics , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/genetics , Esophageal Squamous Cell Carcinoma/pathology , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , MicroRNAs/metabolism
16.
Dev Comp Immunol ; 152: 105110, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38081403

ABSTRACT

IL-22 is a critical cytokine of epithelial mucosal barrier. In humans, IL-22 signals through a heteroduplex receptor consisting of IL-22R and IL-10Rß. In fish, IL-22 and its receptors homologues have been cloned in a number of species, however, no studies have been reported how the receptors are involved in IL-22 transduction. For this purpose, in this study we identified IL-22 and its soluble receptor IL-22BP and transmembrane receptors IL-22RA1 and IL-10R2 in Carassius cuvieri × Carassius auratus red var. (named WR-IL-22, WR-IL-22BP, WR-IL10R2 and WR-IL22RA1, respectively). WR-IL-22, WR-IL-22BP, WR-IL10R2 and WR-IL22RA1 were relatively conserved in the evolutionary process, sharing the same conserved domains as their higher vertebrate homologues. When the fish were infected with the Aeromonas hydrophila, the expression of WR-IL-22, WR-IL-22BP, WR-IL10R2 and WR-IL22RA1 were significantly induced in the gut. The co-IP assay showed that WR-IL-22 not only interacted with WR-IL-22BP, but also with WR-IL10R2 and WR-IL22RA1. When introduced in vivo, WR-IL-22 activated the JAK1-STAT3 axis and protected the gut mucosa from A. hydrophila infection. However, overexpression of WR-IL-22BP or knockdown of transmembrane receptors WR-IL10R2 and WR-IL22RA1 significantly inhibited the activation of WR-IL-22-mediated JAK1-STAT3 axis and promoted bacterial colonization in the gut. These results provided new insights into the role of IL-22 and its receptors in the gut mucosa barrier and immune response in teleost.


Subject(s)
Bacterial Infections , Fish Diseases , Humans , Animals , Interleukin-22 , Cytokines/metabolism , Carrier Proteins , Mucous Membrane/metabolism , Aeromonas hydrophila/metabolism , Fish Proteins/genetics , Fish Proteins/metabolism
17.
Polymers (Basel) ; 15(19)2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37835947

ABSTRACT

To address the issue of pipeline blockage caused by the formation of waxy deposits inside pipelines, hindering the flow of petroleum in the Shengli oilfield, eight new-style polyacrylic acid pour point depressants (PPD) for Shengli crude oil were prepared by maleic anhydride and ene monomers with different polar and aromatic pendant chains. The synthesized Pour Point Depressants were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and polarizing optical microscopy (POM). The results were promising and demonstrated that any type of pour point depressant exhibited excellent performance on high-pour-point crude oil. The reduction in pour-point after additive addition was largely dependent on the polymer structure. Notably, polymers containing long alkyl side chains and aromatic units displayed the most impressive performance, capable of depressing the pour point by 12 °C.

18.
Environ Monit Assess ; 195(11): 1327, 2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37847320

ABSTRACT

In China, coal provides about 56.8% of the energy. Most of China's coal mines are shaft mines, which cause the surface to collapse and crack during the mining process. The soil near the cracks changes its physicochemical properties due to the altered stress conditions. This will affect the distribution of PTEs in the soil. We collected 18 samples from a selected crack in the abandoned land. The pH, Eh, and PTE and their fractions of the samples were determined. With the test results, we understand the distribution characteristics of pH, Eh, PTEs, and their fractions at the cracks. Meanwhile, we explored the key factors that contribute to this distribution. It was determined that crack decreases surface soil pH while increasing Eh. The total amount of 7 PTEs is higher in the bottom soil of the main crack and 2 m away from the main crack. The content of reducible fractions of PTEs increases with the increase of soil Eh. The oxidizable and residual fractions of PTEs adsorbed to the clay particles migrate to and enrich the deeper layers of the main crack. This study emphasizes the effect of crack generation on the distribution of PTEs in soil. It provides insights to describe the distribution of PTE throughout the full life cycle of crack.


Subject(s)
Coal Mining , Metals, Heavy , Soil Pollutants , Metals, Heavy/analysis , Environmental Monitoring/methods , Soil Pollutants/analysis , Mining , Soil/chemistry , China , Coal , Risk Assessment
19.
Org Lett ; 25(37): 6840-6845, 2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37681678

ABSTRACT

A simple and atom-economical one-step protocol is described for the synthesis of biologically valuable 3-isoquinuclidones. The method proceeds from the simple starting materials, α-acyl N-arylcinnamamides, and can be performed under mild conditions in the presence of tBuOK. The key steps of this process are the double Michael addition reaction of a Nazarov-like reagent and the subsequent intramolecular hemiamination. These flexible intermolecular reactions could be performed on a gram scale.

20.
RSC Adv ; 13(39): 27158-27166, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37701284

ABSTRACT

A palladium(ii)-catalyzed intramolecular oxidative aza-Wacker-type reaction of vinyl cyclopropanecarboxamides to access a series of conformationally restricted highly substituted aza[3.1.0]bicycles is reported. The transformation proceeded through a typical aza-Wacker reaction mechanism to forge a new C-N bond with oxygen as the terminal oxidant. The desired fused heterocycles were obtained in moderate yields. The process is tolerant of a range of functional aryl groups under mild conditions.

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