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The secondary metabolites of the aerial parts of Zornia brasiliensis Vogel, Fabaceae, and the biological activity of one of these secondary metabolites were characterized in this ...study. A phytochemical investigation was performed using chromatographic techniques including analytical and preparative reverse-phase HPLC column sequences, which resulted in the isolation of fourteen compounds: one previously undescribed C-glycosylated dihydrochalcone (zornioside), one cyclitol (D-pinitol), one glycosylated megastigmane (roseoside) and eleven phenolic compounds: 7-methoxyflavanone, 7,4′-dimethoxyisoflavone, medicarpin, 2′-4′-dihydroxychalcone, onionin, isoorientin-3′-O-methyl ether, isovitexin, glycosylated (Z)-O-coumaric acid, glycosylated (E)-O-coumaric acid, dihydromelilotoside, and isoorientin. The structures of the isolated compounds were determined based on 1D and 2D-NMR, HRESIMS, IR and CD spectroscopic analyses. The cytotoxic activity of zornoside was assessed against tumor cell lines (MCF-7, HCC1954, T-47D, 4T1, HL60), and a non-tumor cell line (RAW264.7) using MTT assay. The compound zornioside was selectively cytotoxic for HL60 leukemia cells (IC50: 37.26μM).
In the Brazilian Amazon, snakebite envenomings (SBE) disproportionately affect indigenous peoples. Communication between indigenous and biomedical health sectors in regards to SBEs has never been ...explored in this region. This study aims to build an explanatory model (EM) of the indigenous healthcare domain for SBE patients from the perspective of the indigenous caregivers.
This is a qualitative study involving in-depth interviews of eight indigenous caregivers who are representatives of the Tikuna, Kokama and Kambeba ethnic groups, in the Alto Solimões River, western Brazilian Amazon. Data analysis was carried out via deductive thematic analysis. A framework was built containing the explanations based on three explanatory model (EM) components: etiology, course of sickness, and treatment. To indigenous caregivers, snakes are enemies and present conscience and intention. Snakebites have a natural or a supernatural cause, the last being more difficult to prevent and treat. Use of ayahuasca tea is a strategy used by some caregivers to identify the underlying cause of the SBE. Severe or lethal SBEs are understood as having been triggered by sorcery. Treatment is characterized by four components: i) immediate self-care; ii) first care in the village, mostly including tobacco smoking, chants and prayers, combined with the intake of animal bile and emetic plants; iii) a stay in a hospital, to receive antivenom and other treatments; iv) care in the village after hospital discharge, which is a phase of re-establishment of well-being and reintroduction into social life, using tobacco smoking, massages and compresses to the affected limb, and teas of bitter plants. Dietary taboos and behavioral interdictions (avoiding contact with menstruating and pregnant women) prevent complications, relapses, and death, and must be performed up to three months after the snakebite. Caregivers are in favor of antivenom treatment in indigenous areas.
There is a potential for articulation between different healthcare sectors to improve the management of SBEs in the Amazon region, and the aim is to decentralize antivenom treatment so that it occurs in indigenous health centers with the active participation of the indigenous caregivers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Colon cancer is one of the world’s most deadly diseases. Because of its internal location, it is necessary to obtain faster and more efficient diagnostic tools for this organ site. In this context, ...we studied the development of new luminescent nanoprobes (LNPs) as an alternative diagnostic apparatus for detecting this disease. The nanoparticles examined herein are lanthanide-doped sodium yttrium fluoride (NaYF
4
:Ln) and have shown to be promising as investigative devices. However, significant problems with the use of LNPs are the lack of biocompatibility and the targeting of the system to tumor regions. One of the strategies to bypass these problems is to increase of the particle lipophilicity modifying their surfaces with organic compounds that present high similarity to the biological system. In this work, we synthesized six new materials for use in bioimaging techniques obtained from the combination of nanoparticles of NaYF
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:5%Eu with organic aromatic compounds covalently bonded. The materials were characterized structurally and morphologically using XRD and TEM, techniques, which showed the identification of the crystallographic phase β-NaYF
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:5%Eu and its nanometric size (particles smaller than 50 nm). The conjugation process was confirmed by FT-IR spectra analysis and from the TGA profile. Excitation and emission spectra allowed the evaluation of the optical properties of the synthesized compounds. The interaction and cellular uptake was confirmed when HT-29 colon cancer cells were exposed to LNPs, indicating that the developed system has promising applications in bioimaging procedures.
Graphical abstract
Colorectal cancer is one of the most significant types of cancer, ranking second in the world’s mortality cases. As colorectal cancer is often diagnosed at a late stage of disease progression, ...effective treatments are necessary. Therefore, radiotherapy has become a fundamental approach in the treatment of colorectal cancer, especially those based on the use of 177Lu. A potential approach to meet this challenge is the use of nanotechnology through the development of radionuclide-based nanomaterials. In this work, we investigated a SiO2-derived class of nanomaterials formed by the insertion of the coordination complex, based on Eu3+ and pyrimidine-2,6-dicarboxylic acid (DPA), into nanoparticles of amino-functionalized mesoporous silica (EuDPA/SiO2–NH2). The properties of the EuDPA/SiO2–NH2 nanoparticles were initially investigated by SEM, FT-IR, TGA, and luminescence. The cellular uptake of EuDPA/SiO2–NH2 nanoparticles into HT-29 cells was confirmed by fluorescence microscopy. Radioactivity was incorporated into the EuDPA/SiO2–NH2 nanoparticles by replacing a tracer quantity of Eu3+ sites with the lanthanide element 177Lu, which resulted in the composition of a dual-modality probe for both SPECT imaging and tumor radiotherapy. Analysis of 177Lu loading into EuDPA/SiO2–NH2 particles showed efficient incorporation, up to 93% radioactivity into the final compound. The imaging potential of the 177Lu–EuDPA/SiO2–NH2 nanoparticles was investigated by SPECT/CT imaging, a subcutaneous HT-29 mouse model of colorectal cancer. Image analysis showed that tumor localization was maintained after intratumoral administration for up to 48 h. To evaluate the therapeutic potential of 177Lu–EuDPA/SiO2–NH2 nanoparticles, HT-29 xenografts were treated in vivo by direct intratumoral injection. Compared with control (PBS) treatment or treatment with unlabeled EuDPA/SiO2–NH2 nanoparticles, the treatment with 177Lu–EuDPA/SiO2–NH2 nanoparticles resulted in a significantly reduced tumor growth. Together, the results of this study results indicate that 177Lu–EuDPA/SiO2–NH2 is a promising agent for further development in SPECT imaging and clinical treatment of colorectal cancer.
An adsorbent-heater-thermometer nanomaterial, (ZIF-8,EuxTby)@AuNP, based on ZIF-8 (adsorbent), containing Eu3+ and/or Tb3+ ions (thermometer) and gold nanoparticles (AuNPs, heater) was designed, ...synthetized, characterized, and applied to controlled drug release. These composite materials were characterized as core-shell nanocrystals with the AuNPs being the core, around which the crystalline ZIF-8 has grown (shell) and onto which the lanthanide ions have been incorporated or chemosorbed. This shell of ZIF-8 acts as adsorbent of the drugs, the AuNPs act as heaters, while the luminescence intensities of the ligand and the lanthanide ions are used for temperature monitoring. This thermo-responsive material can be activated by visible irradiation to release small molecules in a controlled manner as established for the model pharmaceutical compounds 5-fluorouracil and caffeine. Computer simulations and transition state theory calculations shown that the diffusion of small molecules between neighboring pores in ZIF-8 is severely restricted and involves high-energy barriers. These findings imply that these molecules are uploaded onto and released from the ZIF-8 surface instead of being inside the cavities. This is the first report of ZIF-8 nanocrystals (adsorbents) containing simultaneously lanthanide ions as sensitive nanothermometers and AuNPs as heaters for controlled drug release in a physiological temperature range. These results provide a proof-of-concept that can be applied to other classes of materials, and offer a novel perspective on the design of self-assembly multifunctional thermo-responsive adsorbing materials that are easily prepared and promptly controllable.
•Biocompatible designed drug controlled release nanomaterial.•Thermometry and heating at the nanoscale allow full control of drug release.•Non-cytotoxic nanoheater, nanothermometer, adsorbent multifunctional materials.•Computational atomistic simulations of drug diffusion and release in ZIF-8.
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