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Maize consists of a cereal widely used in the preparation of different food products. Brazil is one of the world's largest maize producers. Several types of pesticides have been applied in ...

BackgroundThe bioactive metabolites production contributes to the resistance of fungi towards adverse environmental conditions. Some metabolites often have interesting health-promoting activities. This study addressed the anti-tumoural properties of Penicillium purpurogenum isolated from a polluted lagoon in Northeastern Brazil.MethodsThe extract obtained from the polished environment strain P. purpurogenum was fermented, filtered, concentrated and lyophilized, giving rise to the Ethyl Acetate Extracellular Extract (EAE). The metabolites of the extracellular extract of P. purpurogenum were studied using direct infusion mass spectrometry. The solid Ehrlic tumor model was used to evaluate the extract antitumor activity. Female Swiss mice were divided in groups (n=10/group) as follow: Negative control (CTL-) treated with phosphate buffered solution; Positive Control (CTL+) treated with cyclophosphamide (25mg/mL); Extracts treatment at doses 4, 20 and 100mg/Kg; Animals without tumor or treatment (Sham); and animals without tumor treated with intermediate dose (EAE20). All treatments were performed intraperitoneally, daily during 15 days. After, the animals were eutanized and the tumor, lymphoid organs and serum were used for immunological, histological and biochemical parameters evaluation.ResultsThe extract was rich in meroterpenoids. All doses of the extract significantly reduced tumor size compared to CLT- and were associated with 100% survival. Histologically, the 20 and 100mg/kg doses reduced tumour-associated inflammation and tumour necrosis. The extract also reduced cellular infiltration of lymphoid organs and circulating TNF-α levels when compared with CLT-. The extract did not induce weight loss and renal or hepatic toxic changes.ConclusionsThese results indicate that P. purpurogenum from a polluted marine environment produce hybrid natural products of the terpenoid pathway that exhibits immunomodulatory and antitumor properties in vivo. Thus, fungal fermentation is a biotechnological approach for the production of antitumour agents.

Maize consists of a cereal widely used in the preparation of different food products. Brazil is one of the world's largest maize producers. Several types of pesticides have been applied in maize crop, which can lead to the contamination of the derived products. The present work aims at the validation of multiresidue method to analyze the matrix effect and level of pesticides in maize flour. Twenty residues were investigated in samples commercialized in the state of Ceará, Brazil. The method was satisfactorily validated, according to parameters recommended by European Union. About 55% of the pesticides had an intense negative matrix effect. Multiresidue analyzes showed the presence of traces of fenitrotion in 20% of maize flour samples. Detected levels were below maximum residue limits recommended for maize. The results indicate that maize products need continuous monitoring to ensure food security.

The Candida genus comprises opportunistic fungi that can become pathogenic when the immune system of the host fails. Candida albicans is the most important and prevalent species. Polyenes, fluoropyrimidines, echinocandins, and azoles are used as commercial antifungal agents to treat candidiasis. However, the presence of intrinsic and developed resistance against azole antifungals has been extensively documented among several Candida species. The advent of original and re-emergence of classical fungal diseases have occurred as a consequence of the development of the antifungal resistance phenomenon. In this way, the development of new satisfactory therapy for fungal diseases persists as a major challenge of present-day medicine. The design of original drugs from traditional medicines provides new promises in the modern clinic. The urgent need includes the development of alternative drugs that are more efficient and tolerant than those traditional already in use. The identification of new substances with potential antifungal effect at low concentrations or in combination is also a possibility. The present review briefly examines the infections caused by Candida species and focuses on the mechanisms of action associated with the traditional agents used to treat those infections, as well as the current understanding of the molecular basis of resistance development in these fungal species. In addition, this review describes some of the promising alternative molecules and/or substances that could be used as anticandidal agents, their mechanisms of action, and their use in combination with traditional drugs.

Upconversion luminescence in erbium-doped PbGeO3–PbF2–CdF2-based vitroceramic under 1540 nm infrared excitation is investigated. Luminescence signals around 410, 525, 550, 660 and 850 nm were generated and attributed to the 2H9/2, 2H11/2, 4S3/2 and 4F9/2 transitions to the 4I15/2 ground-state, and 4S3/2–4I13/2, respectively. The erbium ions excited-state emitting levels were populated through a combination of stepwise ground-state absorption, phonon-assisted excited-state absorption and cross-relaxation processes. The results also disclosed that all emission signals obtained with vitroceramic samples presented intensities three times higher when compared to the precursor glass samples. In addition, the red emission signal at 660 nm for 1540 nm pumping exhibited an expressively high intensity when compared to the green signal.

Background and purpose: Oncocalyxone A (OncoA) has a concentration-dependent anti-platelet activity. The present study aimed to further understand the mechanisms related to this effect. Experimental approach: Human platelet aggregation was measured by means of a turbidimetric method. OncoA (32–256 μM) was tested against several platelet-aggregating agents, such as adenosine diphosphate (ADP), collagen, arachidonic acid (AA), ristocetin and thrombin. Key results: OncoA completely inhibited platelet aggregation with a calculated mean inhibitory concentration (IC50-μM) of 122 for ADP, 161 for collagen, 159 for AA, 169 for ristocetin and 85 for thrombin. The anti-aggregatory activity of OncoA was not inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). OncoA, at a concentration that caused no significant anti-aggregatory activity, potentiated sodium nitroprusside (SNP) anti-aggregatory activity (18.8±2.9%-SNP vs 85.0±8.2%-SNP+OncoA). The levels of nitric oxide (NO) or cAMP were not altered by OncoA while cGMP levels were increased more than 10-fold by OncoA in resting or ADP-activated platelets. Flow cytometry revealed that OncoA does not interact with receptors for fibrinogen, collagen or P-selectin. Nevertheless, OncoA decreased the binding of antibodies to GP Ibα, a glycoprotein that is related both to von Willebrand factor and to thrombin-induced platelet aggregation. Conclusion and implications: OncoA showed anti-aggregatory activity in platelets that was associated with increased cGMP levels, not dependent on NO and with blocking GP Ibα glycoprotein. This new mechanism has the prospect of leading to new anti-thrombotic drugs. British Journal of Pharmacology (2008) 154, 1216–1224; doi:10.1038/bjp.2008.199; published online 2 June 2008

Chromoblastomycosis (CBM) is a chronic, suppurative, granulomatous mycosis of the skin and subcutaneous tissues. The aim of this study was to evaluate the association between IgG antibody levels and the severity of CBM and therapeutic response of patients to itraconazole. A longitudinal study was conducted in patients with CBM due to Fonsecaea pedrosoi and in healthy subjects with chromomycin skin test (CST)+. The dosage of anti-F. pedrosoi IgG antibody performed in 47 healthy individuals with CST+ showed positivity in 97.5 %, with an average titer of 2,109 [standard deviation (SD) + 3,676)] and a mean optical density (OD) of 1.174 (SD + 0.456), showing positive correlation with the induration area of the CST (mm2). The level of antibodies in 55 patients with CBM expressed in OD and titration showed that, before treatment, patients with severe disease had higher levels of IgG, IgG1, IgG2, and IgG3 when compared with moderate or mild disease (p < 0.05). According to the time of treatment, the mean antibody titers of IgG, IgG1, and IgG2 were reduced after treatment (p < 0.05). In the assessment of therapeutic response, there was reduction of IgG3 and IgG titers in patients with rapid response (p < 0.05) and IgG2 on rapid and intermediate response (p < 0.05). There was clear evidence of what are the risk factors for exposure to F. pedrosoi in the daily lives of these subjects, with prospects of preventive measures for the target population. The immunological analysis shows that the antibody anti-F. pedrosoi did not exhibit a protective role against infection caused by this agent.

White light was produced exploiting an additive synthesis of red, green, and blue fluorescence through frequency upconversion in fluorolead-germanate glass codoped with Ho3+, Tm3+, and Yb3+. The 475, 540, and 650nm signals were, respectively, assigned to thulium (G41-H63) and holmium (S25;F45)→I85 and F55→I85, excited via energy tranfer from ytterbium. The dopant concentrations were adjusted, yielding the emission of a wide color gamut in the visible spectrum and the production of white light using excitation at 975nm. The spectral positions and purity (blue, 97%; green, 100%; red, 95%) of the three colors produced CIE-X=0.3438 and CIE-Y=0.3639 coordinates.