Phytoscreening of Vochysiaceae species: Molecular identification by HPLC-ESI-MS/MS and evaluating of their antioxidant activity and inhibitory potential against human α-amylase and protein glycation.

Scientific research based on medicinal plants has been highlighted as a complementary treatment to T2DM, stand out the Vochysiaceae family, which have been widely used in folk medicine by traditional South American communities to treat some diseases. Our study aimed to investigate the antioxidant and antiglycation activities of ethanol extracts of leaves (LF) and stem barks (SB) of Vochysiaceae species, evaluated their capacities to inhibit glycoside and lipid hydrolases related to T2DM and molecular identification by HPLC-ESI-MS/MS. Our main findings indicate that the ethanolic extract of four of eight analyzed plants such as LF and SB of Q. grandiflora, Q. parviflora, V. elliptica and Calisthene major exhibited, respectively, potential of α-amylase inhibition (IC50 of LF: 5.7 ±â€¯0.6, 4.1 ±â€¯0.5, 5.8 ±â€¯0.5, 3.2 ±â€¯0.6 and IC50 of SB: 3.3 ±â€¯0.7, 6.2 ±â€¯2.0, 121.0 ±â€¯8.6 and 11.2 ±â€¯2.8 µg/mL), capacities of antioxidant (ORAC of LF: 516.2 ±â€¯0.1, 547.6 ±â€¯4.9, 544.3 ±â€¯6.1, 442.6 ±â€¯2.4 and ORAC of SB: 593.6 ±â€¯22.3, 497.7 ±â€¯0.8, 578 ±â€¯12.3, 593.6 ±â€¯19.5 µmol trolox eq/g; FRAP of LF: 796.1 ±â€¯0.9, 427.7 ±â€¯22.0, 81.0 ±â€¯1.9, 685 ±â€¯37.9 and FRAP of SB: 947.4 ±â€¯24.9, 738.6 ±â€¯24.3, 98.8 ±â€¯7.9, 970.8 ±â€¯13.9 µmol trolox eq/g; DPPH IC50 of LF: 14.2 ±â€¯1.8, 36.3 ±â€¯6.9, 11.8 ±â€¯1.9, 13.3 ±â€¯1.2 and DPPH IC50 of SB: 16.0 ±â€¯3.0, 15.5 ±â€¯1.9, 126.1 ±â€¯23. 6, 5.3 ±â€¯0.3 µg/mL, respectively) and antiglycation (BSA/Frutose IC50 of LF: 43.1 ±â€¯3.4, 52.1 ±â€¯6.0, 175.5 ±â€¯32, 8, 111.8 ±â€¯14.7 and BSA/Frutose IC50 of SB:, 40.1 ±â€¯11.9, 51.2 ±â€¯16. 7, 46.6 ±â€¯5.7, 53.5 ±â€¯13.6 µg/mL) and presence of polyphenols, such as flavonoids and condensed tannins. The extracts presented low ability to inhibit α-glycosidase and lipase enzymes in the initial assays, with values below 40% of inhibition. In BSA/methylglyoxal, only Q. grandiflora SB, V. eliptica LF and V. tucanorum LF showed activity (IC50: 655.5 ±â€¯208.5, 401.9 ±â€¯135.2 and 617.1 ±â€¯80.6 µg/mL, respectively) and only C. major LF and SB, in Arg/methylglyoxal (IC50: 485.1 ±â€¯130.8 and 468.0 ±â€¯150.5 µg/ml, respectively). This study presented new findings about the biological and pharmacological potential of some species of Vochysiaceae family, contributing to the understanding of the action and efficacy in use of these plants, in their management of postprandial hyperglycemia and in glycation and oxidative processes that contribute to managing diabetes mellitus.

Toxicidade de espécies vegetais / Toxicity of plant species

RESUMO As plantas produzem uma grande variedade de metabólitos secundários que frequentemente são relacionados a mecanismos de proteção da planta contra predadores e patógenos. As espécies tóxicas são aquelas capazes de produzirem compostos que podem causar alterações metabólicas prejudiciais ao homem e aos animais. A toxicidade apresentada por uma espécie vegetal pode estar relacionada a fatores associados ao indivíduo, à planta, ao modo de exposição e a questões ambientais. A intoxicação, aguda ou crônica, causada por plantas é difícil de ser diagnosticada assim como a associação entre os sintomas e o consumo e/ou contato com algumas espécies é difícil de ser estabelecida. No âmbito da saúde pública, as intoxicações causadas por plantas possuem impacto expressivo. No Brasil foram registrados 1026 casos em 2012, sendo que a maior parte deles ocorreu com crianças de 0 a 4 anos, de acordo com os dados do SINITOX. O objetivo deste trabalho foi realizar um levantamento bibliográfico de espécies vegetais, brasileiras e exóticas aclimatadas, citadas como tóxicas apesar de serem utilizadas com fins ornamentais e medicinais.

ABSTRACT Plants produce a wide variety of secondary metabolites, which are frequently related to a plant’s protective mechanism against predators and pathogens. Toxic species are those capable of producing compounds that can cause metabolic changes harmful to humans and animals. The toxicity of plant species can be associated with aspects related to the individual, the plant, the manner of exposure, and to environmental issues. Acute or chronic intoxication caused by plants is difficult to diagnose and the association between the symptoms and the consumption of and/or contact with plants is hard to establish. In the public health sector, intoxications caused by plants have a wide impact. In Brazil, 1,026 cases were registered in 2012, most of which occurred with children between the ages of 0 to 4 years, according to data reported by SINITOX. The purpose of this study was to perform a bibliographic survey of Brazilian or acclimatized exotic plant species, which have been reported as toxic even though they are used for ornamental or medicinal purposes.

Unfolding and refolding studies of frutalin, a tetrameric D-galactose binding lectin.

Protein refolding is currently a fundamental problem in biophysics and molecular biology. We have studied the refolding process of frutalin, a tetrameric lectin that presents structural homology with jacalin but shows a more marked biological activity. The initial state in our refolding puzzle was that proteins were unfolded after thermal denaturation or denaturation induced by guanidine hydrochloride, and under both conditions, frutalin was refolded. The denaturation curves, measured by fluorescence emission, gave values of conformational stability of 17.12 kJ.mol-1 and 12.34 kJ.mol-1, in the presence and absence of d-galactose, respectively. Native, unfolded, refolded frutalin and a distinct molecular form denoted misfolded, were separated by size-exclusion chromatography (SEC) on Superdex 75. The native and unfolded samples together with the fractions separated by SEC were also analyzed for heamagglutination activity by CD and fluorescence spectroscopy. The secondary structure content of refolded frutalin estimated from the CD spectra was found to be close to that of the native molecule. All the results obtained confirmed the successful refolding of the protein and suggested a nucleation-condensation mechanism, whereby the sugar-binding site acts as a nucleus to initiate the refolding process. The refolded monomers, after adopting their native three-dimensional structures, spontaneously assemble to form tetramers.

Arterial, peritoneal, and intraventricular access devices.

OBJECTIVE: To provide an overview of access devices used to treat cancers through the arterial, peritoneal, and intraventricular body systems. CONCLUSIONS: Short-term and long-term devices have been developed over the last 35 years for cancer treatment. Although less amenable to standard methods of therapy, the various access devices available to access the arterial, peritoneal, and intraventricular systems have provided a safe and reliable means for drug therapy. Access devices assist in delivering high concentrations of drugs directly to the center of the tumor. Complications and toxicities are inherent with these devices from the drug therapy as well as the device. Nursing assessment can provide early identification of potential problems and implementation of appropriate interventions. IMPLICATIONS FOR NURSING PRACTICE: As the availability of these devices increases, so must the nurse's knowledge base to provide optimal safe care. Oncology nurses are challenged to know the differences between the devices, the device of choice for the individual patient, insertion procedures, and maintenance protocols.

Phase II study of hepatic arterial floxuridine, leucovorin, and dexamethasone for unresectable liver metastases from colorectal carcinoma.

PURPOSE: To determine the toxicity, response rate, and survival of a regimen of hepatic arterial floxuridine (FUDR) with leucovorin (LV) and dexamethasone (Dec) for the treatment of unresectable hepatic metastases from colorectal carcinoma. PATIENTS AND METHODS: Sixty-two patients with hepatic metastases (33 previously untreated with chemotherapy) were treated with FUDR (0.30 mg/kg/d) and LV (15 mg/m2/d) and Dec (20 mg total dose) as a 14-day hepatic arterial infusion via an implantable pump alternating with 2 weeks of saline. RESULTS: The complete response (CR) plus partial response (PR) rate was 78% in previously untreated patients, with a median survival duration of 24.8 months; 1- and 2-year survival rates were 91% and 57%, respectively. In the previously treated group, the response rate was 52%, with a median survival duration of 13.5 months. Only 3% of patients (two of 62) developed biliary sclerosis; this was significantly lower than the 21% biliary sclerosis rate observed in our previous trial of hepatic arterial FUDR and LV without Dec (P = .002). CONCLUSION: The addition of Dec to hepatic arterial FUDR and LV reduces biliary toxicity while maintaining an excellent response rate and survival. We recommend that this treatment be studied further.