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Periaqueductal gray (PAG) is a midbrain region that projects to areas controlling behavioral and autonomic outputs and is involved in the behavioral and physiological components of defense reactions. Since Raphe Pallidus (RPa) is a medial medullary region comprising sympathetic premotor neurons governing heart function, it is worth considering the PAG-RPa path. We assessed: i) whether PAG projects to RPa; ii) the amplitude of cardiac responses evoked from PAG; iii) whether cardiovascular responses evoked from PAG rely on RPa. Experiments conducted in Wistar rats (±300 g) were approved by Ethics Committee CEUA-UFG (092/18). Firstly, (n = 3), monosynaptic retrograde tracer Retrobeads was injected into RPa; PAG slices were analyzed. Other two groups (n = 6 each) were anesthetized with urethane (1.4 g/kg) and chloralose (120 mg/kg) and underwent craniotomy, tracheostomy, catheterization of femoral artery and vein and of cardiac left ventricle. In one group, we injected the GABAA receptor antagonist, bicuculline methiodide (BMI - 40 pmol/100 nL) into lateral/dorsolateral PAG. Another group was injected (100 nL) with the GABAA receptor agonist muscimol (20 mM) into RPa, 20 min before BMI into PAG. The results were: i) retrogradely labelled neurons were found in PAG; ii) PAG activation by BMI caused positive chronotropism and inotropism, which were accompanied by afterload increases; iii) RPa inhibition with Muscimol reduced heart rate, arterial and ventricular pressures; iv) the subsequent PAG activation still increased arterial pressure, cardiac chronotropy and inotropy, but these responses were significantly attenuated. In conclusion, PAG activation increases cardiac chronotropy and inotropy, and these responses seem to rely on a direct pathway reaching ventromedial medullary RPa neurons.

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Photodynamic therapy (PDT) has proven to be an effective alternative for the treatment of cutaneous leishmaniasis. Skin lesions consist of ulcers with well-defined raised edges, and granular floor. Th1 immune response is the protective profile in patients infected with Leishmania. In this study, the photodynamic therapy with 5-aminolevulinic acid, the parasitic load, and the modulation of the immune response was evaluated in mice infected with Leishmania braziliensis. Balb/c mice were infected with L. braziliensis and subsequently treated with three sections of PDT. The parasite load and mRNA expression of cytokines (IFN-γ, IL-4, IL-17, IL-22, IL-27, IL-10) and transcription factors (GATA-3, Foxp3 and T-bet) were analysed by quantitative PCR. The parasite load in the treated group was significantly lower than in the untreated group (P<.0001); in PDT treated animals, we observed an increase in IFN-γ and T-bet mRNA (P=.012 and P=.0071). There was a significant reduction in mRNA expression of IL-22 associated with an increased expression of IL-27 mRNA in the animals treated with light only (P=.0001). 5-ALA associated with photodynamic therapy promotes a reduction in parasite load and an increased expression of IFN-γ and T-bet mRNA.

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The interest upon products obtained from fungi has increased during the recent years. Among the most noticeable, nutraceuticals, enzymes, and natural drugs occupy a privileged position. Fungal biomass for the obtainment of those products can be produced either by solid-state fermentation (SSF) or submersed fermentation. SSF has been employed for the production of spawn on pretreated wheat grains with the objective of increasing the fungal polysaccharide (glucomannans) contents. Among the important factors for the production of spawn, time of cooking, time of resting after grain cooking, consequently grain moisture, substrate pH, temperature of incubation, and initial inoculum amount are among the most significant. For wheat grains, cooking time of 21 min followed by a 24-min resting time has been shown as optimal for the production of glucomannans by the fungus Agaricus subrufescens (=Agaricus brasiliensis). Amendments of CaSO(4) (up to 3 %) and CaCO(3) (up to 1 %) had an important influence on the substrate pH. In general, better results for glucomannan production were obtained when no supplement was added or when up to 0.25 % CaCO(3) (pH 6.6) has been added to the mix. Our results demonstrate that the inoculum amount necessary for the best polysaccharide levels is around 10.3 %, while the best temperature is around 27.2 °C. Besides using the spawn for its main purpose, it could potentially and alternatively be used as nutraceutical due to the high levels of glucomannan observed (6.89 %), a compound technically proven to be a potent immunostimulatory and antitumoral agent.

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ABSTRACT FUNGI IN THE BIOREMEDIATION OF DEGRADED AREAS. The increase in industrial ac tivities has intensified environmental pollution, promoting the improper disposal of household and industrial waste, especially hazardous waste, resulting in contamination of soil, air, surface water and groundwater resources. One of the technologies used in the recovery of these degraded areas is bioremediation, which uses microorganisms as recovery agents. Therefore, this review aims to address the main aspects of bioremediation by fungi mycoremediation of contaminated soil based on various previously published studies available in major databases such as SciELO, LILACS, HighWire, PubMed. This biotechnology has been used for years in other countries, and in some cases has lower cost and higher efficiency in removal of contaminants than the physical and chemical techniques that are currently used on a commercial scale in the treatment of various wastes and the remediation of degraded areas. It is therefore necessary to develop further studies to understand the mechanisms of bioremediation mediated by microorganisms, as a biological tool in fighting pollution.

RESUMO O aumento das atividades industriais tem intensificado a poluição ambiental, promovendo a disposição inadequada de resíduos domésticos e industriais, principalmente resíduos perniciosos, implicando na contaminação do solo, ar, recursos hídricos superficiais e subterrâneos. Dentre as tecnologias mais utilizadas na recuperação dessas áreas degradadas, destaca-se a biorremediação, que tem, como agentes recuperadores, os micro-organismos. Portanto, o presente trabalho de revisão tem por objetivo abordar os principais aspectos da biorremediação por fungos micorremediação de solos contaminados baseados nas diversas pesquisas já publicadas e disponíveis nos principais bancos de dados, tais como SciELO, LILACS, HighWire e PubMed. Essa biotecnologia vem sendo utilizada há vários anos em outros países e, em certos casos, apresenta menor custo e maior eficiência na remoção dos contaminantes do que as técnicas físicas e químicas que são atualmente utilizadas em escala comercial no tratamento de diversos resíduos e na remediação de áreas degradadas. Diante disso, é necessário que sejam realizados mais estudos para compreender os mecanismos de biorremediação mediada por micro-organismos, como ferramenta biológica no combate a poluição.

RESUMO

O aumento das atividades industriais tem intensificado a poluição ambiental, promovendo a disposição inadequada de resíduos domésticos e industriais, principalmente resíduos perniciosos, implicando na contaminação do solo, ar, recursos hídricos superficiais e subterrâneos. Dentre as tecnologias mais utilizadas na recuperação dessas áreas degradadas, destaca-se a biorremediação, que tem, como agentes recuperadores, os micro-organismos. Portanto, o presente trabalho de revisão tem por objetivo abordar os principais aspectos da biorremediação por fungos ­ micorremediação de solos contaminados baseados nas diversas pesquisas já publicadas e disponíveis nos principais bancos de dados, tais como SciELO, LILACS, HighWire e PubMed. Essa biotecnologia vem sendo utilizada há vários anos em outros países e, em certos casos, apresenta menor custo e maior eficiência na remoção dos contaminantes do que as técnicas físicas e químicas que são atualmente utilizadas em escala comercial no tratamento de diversos resíduos e na remediação de áreas degradadas. Diante disso, é necessário que sejam realizados mais estudos para compreender os mecanismos de biorremediação mediada por micro-organismos, como ferramenta biológica no combate a poluição.

The increase in industrial ac tivities has intensified environmental pollution, promoting the improper disposal of household and industrial waste, especially hazardous waste, resulting in contamination of soil, air, surface water and groundwater resources. One of the technologies used in the recovery of these degraded areas is bioremediation, which uses microorganisms as recovery agents. Therefore, this review aims to address the main aspects of bioremediation by fungi ­ mycoremediation of contaminated soil based on various previously published studies available in major databases such as SciELO, LILACS, HighWire, PubMed. This biotechnology has been used for years in other countries, and in some cases has lower cost and higher efficiency in removal of contaminants than the physical and chemical techniques that are currently used on a commercial scale in the treatment of various wastes and the remediation of degraded areas. It is therefore necessary to develop further studies to understand the mechanisms of bioremediation mediated by microorganisms, as a biological tool in fighting pollution.

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This study aimed to assess physicochemical and microbiological properties of fresh spent mushroom substrates (SMSs)--without post-crop heat treatment--from Agaricus subrufescens and Lentinula edodes production to optimize the use of these residues in the soil enrichment for lettuce growth promotion and soil remediation. Organic matter and C content of both SMSs were high. Fresh A. subrufescens SMS was a good source of N, P and K. On the other hand, L. edodes SMS presented a lower concentration of these nutrients and a high level of immaturity. Both SMSs presented high electric conductivity values (2.5-3.4 mS/cm). Microbiological analysis, based upon enumeration of culturable bacteria (thermophilic and mesophilic) and fungi, and also evolution of CO(2), showed that SMSs played higher microbial diversity than soil control. Laccase activity from A. subrufescens SMS tended to remain constant during a 2-month period, while L. edodes SMS presented low laccase activity throughout the same period. Agaricus subrufescens and L. edodes were able to grow on a PDA (Potato Dextrose Agar) media supplemented with different concentrations of atrazine (1-50 microg/ml), degraded the herbicide, attaining rates of 35% and 26%, respectively. On experiments of lettuce growth promotion using a soil-based potting media with different SMS rates, 5% and 10% (dw) rates of A. subrufescens SMS resulted in higher lettuce aerial dry weights than the rates of 25% and 40%, the chemical fertilization (NPK) and the control (soil). At 10% supplementation, lettuce aerial dry weight increased 2.2 and 1.3 times compared to the control and the NPK treatment, respectively. Protein content increased along with SMS rates. Fresh A. subrufescens SMS was an excellent supplement for lettuce growth promotion and showed potential for remediation of biocides possibly due to improved microbial diversity and enzymatic activity. Fresh L. edodes SMS was not a good fertilizer, at least under the conditions tested. However, microbiological analysis showed that promising results may be achieved when using fresh L. edodes SMS for soil remediation.

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