A one-step thermal decomposition strategy, in which a novel reductant participated, was developed to prepare superparamagnetic nearly cubic monodisperse Fe 3 O 4 nanoparticles loaded on multiwall carbon nanotubes (MWCNTs/Fe 3 O 4 ). Subsequently, the as-prepared MWCNTs/Fe 3 O 4 nanocomposites were modified with 3-aminopropyltriethoxysilane (APTS) (MWCNTs/Fe 3 O 4 -NH 2 ). The materials were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM) and the BET surface area method. The results indicated that superparamagnetic Fe 3 O 4 nanoparticles were successfully loaded onto the surface of the MWCNTs, and APTS was also modified on the MWCNTs/Fe 3 O 4 magnetic nanocomposites. The two as-prepared magnetic nanocomposites were used as adsorbents to remove tetrabromobisphenol A (TBBPA) and Pb(II) from wastewater. The adsorption kinetics and adsorption isotherms of TBBPA and Pb(II) on the two asprepared adsorbents were studied at pH 7.0 and 5.3, respectively. It was revealed that MWCNTs/ Fe 3 O 4 -NH 2 performed better than the MWCNTs/Fe 3 O 4 nanocomposites for the adsorption properties of TBBPA and Pb(II). After adsorption, both adsorbents could be conveniently separated from the media by an external magnetic field within several seconds, and regenerated in 0.1 M NaOH solution.
Metabolite lactic acid has always been regarded as a metabolic by-product rather than a bioactive molecule. Recently, this view has changed since it was discovered that lactic acid can be used as a signal molecule and has novel signal transduction functions both intracellular and extracellular, which can regulate key functions in the immune system. in recent years, more and more evidence has shown that lactic acid is closely related to the metabolism and polarization of macrophages. During inflammation, lactic acid is a regulator of macrophage metabolism, and it can prevent excessive inflammatory responses; in malignant tumors, lactic acid produced by tumor tissues promotes the polarization of tumor-associated macrophages, which in turn promotes tumor progression. in this review, we examined the relationship between lactic acid and macrophage metabolism. we further discussed how lactic acid plays a role in maintaining the homeostasis of macrophages, as well as the biology of macrophage polarization and the M1/M2 imbalance in human diseases. Potential methods to target lactic acid in the treatment of inflammation and cancer will also be discussed so as to provide new strategies for the treatment of diseases.
Nitric oxide (NO)
gas therapy has aroused intense interest in recent
years. l-Arginine (l-Arg) reacts with reactive oxygen
species (ROS) in tumor cells to generate NO. This phenomenon represents
an effective method for tumor therapy. However, endogenous ROS levels
in most types of tumor cells cannot enable an effective reaction.
β-Lapachone is generally used to increase H2O2, which can oxidize guanidine derivatives to form nitric oxide
in tumor cells. In addition, based on the ferrocene (Fc)-catalyzed
Fenton reaction, ·OH is generated from H2O2, and the ONOO– could be generated from an interaction
between ·O2
– (generated through
the Haber–Weiss reaction) and NO. Arg-rich poly(ε-caprolactone)
(PCL)-b-PArg, a macromolecular NO donor, was accurately synthesized
to avoid premature l-Arg leakage during in vivo transport.
In this design, the self-assembled PCL-b-PArg nanoparticles were dressed
with the tumor-shreddable masking (PEG-b-PDMA, a negatively charged
pH-sensitive hydrophilic diblock polymer), to prepare P-lapa-Fc nanoparticles
and hide penetrative capability in the circulation. The experimental
results confirmed that this synergistic therapy based on ROS and NO
had a significant inhibitory effect on cancer cells, thereby providing
new inspiration for NO gas treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.