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Oil-in-water nanoemulsions (NEs) are considered a suitable nanotechnological approach to improve the eye-related bioavailability of lipophilic drugs. The potential of cationic NEs is prominent due to the electrostatic interaction that occurs between the positively charged droplets with the negatively charged mucins present in the tear film. This interaction offers prolonged NEs residence at the ocular surface, increasing the drug absorption. Triamcinolone acetonide (TA) is one of the first pharmacologic strategies applied as an intravitreal injection in the treatment of age-related macular degeneration (AMD). Newly synthesized quaternary derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and quinuclidine surfactants have been screened with the purpose to select the best compound to formulate long-term stable NEs that combine the best physicochemical properties for the loading of TA intended for ocular administration., This work was funded by the Portuguese Science and Technology Foundation (FCT) from the Ministry of Science and Technology (MCTES), European Social Fund (FSE) of EU, for the scholar ship SFRH/BD/130555/2017 granted to A. R. Fernandes, and for the projects UIDB/04469/2020 (CEB strategic fund) and UIDB/04033/2020 (CITAB), co-funded by European Funds (PRODER/COMPETE) and FEDER, under the Partnership Agreement PT2020., info:eu-repo/semantics/publishedVersion

Quaternary derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and of quinuclidine surfactants were used to develop oil-in-water nanoemulsions with the purpose of selecting the best long-term stable nanoemulsion for the ocular administration of triamcinolone acetonide (TA). The combination of the best physicochemical properties (i.e., mean droplet size, polydispersity index, zeta potential, osmolality, viscoelastic properties, surface tension) was considered, together with the cell viability assays in ARPE-19 and HMC3 cell lines. Surfactants with cationic properties have been used to tailor the nanoemulsions surface for site-specific delivery of drugs to the ocular structure for the delivery of TA. They are tailored for the eye because they have cationic properties that interact with the anionic surface of the eye., Portuguese Science and Technology Foundation (FCT) from the Ministry of Science and Technology (MCTES), European Social Fund (FSE) of the EU, for the scholarship SFRH/BD/130555/2017 granted to A. R. Fernandes, and for the projects UIDB/04469/2020 (CEB strategic fund) and UIDB/04033/2020 (CITAB), co-funded by European Funds (PRODER/COMPETE) and FEDER, under the Partnership Agreement PT2020, info:eu-repo/semantics/publishedVersion

Probiotics are increasingly gaining popularity in vast food applications due to their recognized health benefits to the host. However, their passage through the gastrointestinal (GI) tract is not smooth and a significant number of physiological barriers (e.g. low pH, bile salts, enzymes, peristaltic movements, etc.) may considerably affect their viability. The entrapment of probiotics in protective matrices, such as hydrogel particles, is a feasible approach to minimize cell death. Therefore, in this work, novel cellulose/chitosan-based particles have been developed to entrap model probiotic Lactobacillus rhamnosus GG. The particle aging, storing and stability was studied at different temperatures and in simulated GI fluids with and without cross-linking agents or protein and lipid additives. Moreover, the effect of the particles on a model intestinal cell line was evaluated. The formulations containing casein displayed the best bacterial survival/culturability when exposed to the GI fluids. Overall, the storage and viability of the probiotics were observed to be improved in the different biopolymer-based systems, generally presenting a low toxicity profile to the cell line. Thus, the particles, which were based on carboxymethyl cellulose and chitosan, may be regarded as interesting matrices for probiotic encapsulation and delivery in food products.

New mesoporous silk fibroin (SF)/silica hybrids were processed via a one-pot soft and energy-efficient sol-gel chemistry and self-assembly from a silica precursor, an acidic or basic catalyst, and the ionic liquid 1-butyl-3-methylimidazolium chloride, acting as both solvent and mesoporosity-inducer. The as-prepared materials were obtained as slightly transparent-opaque, amorphous monoliths, easily transformed into powders, and stable up to ca. 300 degrees C. Structural data suggest the formation of a hexagonal mesostructure with low range order and apparent surface areas, pore volumes, and pore radii of 205-263 m(2) g(-1), 0.16-0.19 cm(3) g(-1), and 1.2-1.6 nm, respectively. In all samples, the dominating conformation of the SF chains is the beta-sheet. Cytotoxicity/bioactivity resazurin assays and fluorescence microscopy demonstrate the high viability of MC3T3 pre-osteoblasts to indirect (>= 99 +/- 9%) and direct (78 +/- 2 to 99 +/- 13%) contact with the SF/silica materials. Considering their properties and further improvements, these systems are promising candidates to be explored in bone tissue engineering. They also offer excellent prospects as electrolytes for solid-state electrochemical devices, in particular for fuel cells., This work was supported by Fundacao para a Ciencia e a Tecnologia (FCT)/Deutscher Akademischer Austauschdienst (DAAD) Transnational Cooperation Project no. 6818 "Ionic liquid-and ionic liquid crystal-assisted formation of hybrid biomaterials scaffolds". We further wish to thank the European Union, QREN, FEDER through "Programa Operacional Factores de Competitividade" (COMPETE), and CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. This work was also funded by project UniRCell (POCI-01-0145-FEDER-016422 and SAICTPAC/0032/2015) financed by the European Regional Development Fund (ERDF) through COMPETE 2020, POCI and FCT. We also thank FCT in the framework of Strategic Funding UID/QUI/00686/2013 and UID/QUI/00686/2016, and funding under project PEst-OE/QUI/UI0616/2014. R.F.P.P. acknowledges FCT for a grant (SFRH/BPD/87759/2012).

Organic photovoltaic devices (OPVs) have a shorter working lifespan and lower power conversion efficiency if compared to traditional silicon-based solar cells. Intending to increase the lifespan and improve the performance of OPVs, in this work we have applied a layer of Cadmium Sulfide (CdS) Quantum Dots (QDs) encapsulated in Zinc Sulfide (CdS/ZnS) to act as a luminescence down-shifting (LDS) layer in poly(3-hexylthiophene-2,5-diyl) (P3HT):phenyl-C61-butyric-acid-methyl ester (PCBM) organic solar cell. The QDs were synthesized by the hot injection route and deposited by casting on a device with ITO/PEDOT:PSS/P3HT:PCBM/Al structure. OPVs with and without the LDS layer of QDs were tested over time of exposure to the illumination of an AM1.5 solar simulator. The results showed that in the cells with the QDs layer, there was an increase in Open Circuit Voltage (Voc), Short Circuit Current Density (Jsc), Fill Factor (FF), and Power Conversion Efficiency (η), after 70 min of exposure, reaching a peak of these parameter values around 120 min of light exposure, while in the cells without the LDS layer, these parameters have decreased over the entire exposure time. This behavior was explained taking into account the improvement of the photoluminescence (PL) yield by the QDs film and the illumination process.

The recently described ‘gasomediator’ hydrogen sulfide (H2S) has been involved in pain mechanisms, but its effect on pruritus, a sensory modality that similarly to pain acts as a protective mechanism, is poorly known and controversial. The effects of the slow-releasing (GYY4137) and spontaneous H2S donors (Na2S and Lawesson’s reagent, LR) were evaluated in histamine and compound 48/80 (C48/80)-dependent dorsal skin pruritus and inflammation in male BALB/c mice. Animals were intradermally (i.d.) injected with C48/80 (3 μg/site) or histamine (1 μmol/site) alone or co-injected with Na2S, LR or GYY4137 (within the 0.3–100 nmol range). The involvement of endogenous H2S and KATP channel-dependent mechanism were also evaluated. Pruritus was assessed by the number of scratching bouts, whilst skin inflammation was evaluated by the extravascular accumulation of intravenously injected 125I-albumin (plasma extravasation) and myeloperoxidase (MPO) activity (neutrophil recruitment). Histamine or C48/80 significantly evoked itching behavior paralleled by plasma extravasation and increased MPO activity. Na2S and LR significantly ameliorated histamine or C48/80-induced pruritus and inflammation, although these effects were less pronounced or absent with GYY4137. Inhibition of endogenous H2S synthesis increased both Tyrode and C48/80-induced responses in the skin, whereas the blockade of KATP channels by glibenclamide did not. H2S-releasing donors significantly attenuate C48/80-induced mast cell degranulation either in vivo or in vitro. We provide first evidences that H2S donors confer protective effect against histamine-mediated acute pruritus and cutaneous inflammation. These effects can be mediated, at least in part, by stabilizing mast cells, known to contain multiple mediators and to be primary initiators of allergic processes, thus making of H2S donors a potential alternative/complementary therapy for treating inflammatory allergic skin diseases and related pruritus.

BackgroundMembers of the family of NEK protein kinases (NIMA-related kinases) were described to have crucial roles in regulating different aspects of the cell cycle. NEK10 was reported to take part in the maintenance of the G2/M checkpoint after exposure to ultraviolet light. NEK1, NEK5, NEK2 and NEK4 proteins on the other hand have been linked to mitochondrial functions.MethodsHEK293T cells were transfected with FLAG empty vector or FLAG-NEK10 and treated or not with Zeocin. For proteomic analysis, proteins co-precipitated with the FLAG constructs were digested by trypsin, and then analyzed via LC-MS/MS. Proteomic data retrieved were next submitted to Integrated Interactome System analysis and differentially expressed proteins were attributed to Gene Ontology biological processes and assembled in protein networks by Cytoscape. For functional, cellular and molecular analyses two stable Nek10 silenced HeLa cell clones were established.ResultsHere, we discovered the following possible new NEK10 protein interactors, related to mitochondrial functions: SIRT3, ATAD3A, ATAD3B, and OAT. After zeocin treatment, the spectrum of mitochondrial interactors increased by the proteins: FKBP4, TXN, PFDN2, ATAD3B, MRPL12, ATP5J, DUT, YWHAE, CS, SIRT3, HSPA9, PDHB, GLUD1, DDX3X, and APEX1. We confirmed the interaction of NEK10 and GLUD1 by proximity ligation assay and confocal microscopy. Furthermore, we demonstrated that NEK10-depleted cells showed more fragmented mitochondria compared to the control cells. The knock down of NEK10 resulted further in changes in mitochondrial reactive oxygen species (ROS) levels, decreased citrate synthase activity, and culminated in inhibition of mitochondrial respiration, affecting particularly ATP-linked oxygen consumption rate and spare capacity. NEK10 depletion also decreased the ratio of mtDNA amplification, possibly due to DNA damage. However, the total mtDNA content increased, suggesting that NEK10 may be involved in the control of mtDNA content.ConclusionsTaken together these data place NEK10 as a novel regulatory player in mitochondrial homeostasis and energy metabolism.

Polymers such as the biocompatible polyhydroxybutyrate (PHB) and the polysaccharide chitosan (Chi), a pH-sensitive polymer, have been studied for drug delivery applications and scaffolds production. In this work, matrices of PHB and Chi were produced by compression molding (SPHB-Chi) and loaded with a broad-spectrum biocide chlorhexidine (CHX) (SPHB-Chi-CHX). The matrices were analyzed by scanning electron microscope (SEM). The SPHB-Chi capacity to absorb and deliver CHX was evaluated by UV-Vis. The antibacterial activity of the samples against S. aureus, P. aeruginosa and E. coli (most common pathogens that cause infection in several body sites) was evaluated using the disk-agar diffusion method. The CHX release results were fitted by the Power Law model. The results suggested that the morphology and the CHX delivery profile were directly related to the Chi amount in the samples and also showed that the SPHB-Chi-CHX is able to inhibit the microorganism proliferation, constituting it as a potential candidate for oral applications.

Sodium channels are highly expressed in nociceptive sensory neurons during hypernociceptive conditions. Based on the presence of a glycosidic portion in the sodium channel β subunit associated to the antinociceptive effect of leguminous lectins via lectin domain, this study investigated the antinociceptive activity of the lectin isolated from Lonchocarpus araripensis seeds (LAL) in mice behavioral models and in NaV current in the nociceptor of rat dorsal root ganglion (DRG).LAL antinociceptive activity and the participation of opioid system, lectin domain and sodium channels were evaluated in Swiss mice models of nociception (formalin, capsaicin, hot plate, tail flick, von Frey) and in primary cultures of Wistar rats neurons of DRG (patch clamp).LAL presented inhibitory effects in the nociception induced by chemical and mechanical, but not by thermal stimuli and reduced total Na(+) current. LAL activity was inhibited by the lectin association with its binding sugar N-acethyl-glucosamine.LAL inhibits peripheral hypernociception by mechanisms that involve the lectin domain, inflammatory mediators and Na(+) channels. The innovative inhibitory action of leguminous lectins on NaV current brings new insights for the investigation of sodium channels role in nociception.

High diesel exhaust particle levels are associated with increased health effects; however, knowledge on the impact of its chemical contaminant 1,2-naphthoquinone (1,2-NQ) is limited. We investigated whether postnatal and adult exposures to 1,2-NQ influence allergic reaction and the roles of innate and adaptive immunity. Male neonate (6 days) and adult (56 days) C57Bl/6 mice were exposed to 1,2-NQ (100 nM; 15 min) for 3 days, and on day 59, they were sensitized and later challenged with ovalbumin (OVA). Airway hyper-responsiveness (AHR) and production of cytokines, immunoglobulin E (IgE) and leukotriene B4 (LTB4) were measured in the airways. Postnatal exposure to 1,2-NQ activated dendritic cells in splenocytes by increasing expressing cell surface molecules (e.g., CD11c). Co-exposure to OVA effectively polarized T helper (Th) type 2 (Th2) by secreting Th2-mediated cytokines. Re-stimulation with unspecific stimuli (PMA and ionomycin) generated a mixed Th1 (CD4(+)/IFN-γ(+)) and Th17 (CD4(+)/IL-17(+)) phenotype in comparison with the vehicle-matched group. Postnatal exposure to 1,2-NQ did not induce eosinophilia in the airways at adulthood, although it evoked neutrophilia and exacerbated OVA-induced eosinophilia, Th2 cytokines, IgE and LTB4 production without affecting AHR and mast cell degranulation. At adulthood, 1,2-NQ exposure evoked neutrophilia and increased Th1/Th2 cytokine levels, but failed to affect OVA-induced eosinophilia. In conclusion, postnatal exposure to 1,2-NQ increases the susceptibility to antigen-induced asthma. The mechanism appears to be dependent on increased expression of co-stimulatory molecules, which leads to cell presentation amplification, Th2 polarization and enhanced LTB4, humoral response and Th1/Th2 cytokines. These findings may be useful for future investigations on treatments focused on pulmonary illnesses observed in children living in heavy polluted areas.

In this study aimed to evaluate the possibility of using industrial boiler ash and rice husk ash in removing the commercial pesticide (carbofuran) in aqueous solution. These solids were collected in the Barreiras/BA, were heat treated and characterized by XRD and FT-IR. The adsorption experiments were performed in batch and the carbofuran removal was quantified using the spectrophotometry in the UV region. XRD data showed high silica content in boiler ash, which was reinforced by FT-IR analyses, showing the band FT-IR associated with presence of silica. In the FT-IR analysis of rice husk ash, this band relative to silica also were observed. The potential of adsorption of the ash industrial boiler and rice husk ash was verified obtaining significant results in the removal of carbofuran at low concentrations (2 mg/L), showing 100% of removal of pesticides from 720 min, used the ash industrial boiler, giving these materials a promising character as adsorbents. In the kinetic study of carbofuran adsorption, the mechanism of pseudo-second-order was better adjusted using the RHA as adsorbent, with a correlation coefficient (R2) of 0.997. The adsorption equilibrium was adjusted better to model of adsorption isotherm of Freundlich with a correlation coefficient of 0.999. DOI: http://dx.doi.org/10.17807/orbital.v1i1.716

Background and purpose: Recent findings suggest that the noxious gas H2S is produced endogenously, and that physiological concentrations of H2S are able to modulate pain and inflammation in rodents. This study was undertaken to evaluate the ability of endogenous and exogenous H2S to modulate carrageenan-induced synovitis in the rat knee. Experimental approach: Synovitis was induced in Wistar rats by intra-articular injection of carrageenan into the knee joint. Sixty minutes prior to carrageenan injection, the rats were pretreated with indomethacin, an inhibitor of H2S formation (dl-propargylglycine) or an H2S donor [Lawesson's reagent (LR)]. Key results: Injection of carrageenan evoked knee inflammation, pain as characterized by impaired gait, secondary tactile allodynia of the ipsilateral hindpaw, joint swelling, histological changes, inflammatory cell infiltration, increased synovial myeloperoxidase, protein nitrotyrosine residues, inducible NOS (iNOS) activity and NO production. Pretreatment with LR or indomethacin significantly attenuated the pain responses, and all the inflammatory and biochemical changes, except for the increased iNOS activity, NO production and 3-NT. Propargylglycine pretreatment potentiated synovial iNOS activity (and NO production), and enhanced macrophage infiltration, but had no effect on other inflammatory parameters. Conclusions and implications: Whereas exogenous H2S delivered to the knee joint can produce a significant anti-inflammatory and anti-nociceptive effect, locally produced H2S exerts little immunomodulatory effect. These data further support the development and use of H2S donors as potential alternatives (or complementary therapies) to the available anti-inflammatory compounds used for treatment of joint inflammation or relief of its symptoms.

Background Non-steroidal antiinflammatory drugs (NSAIDs) are the most commonly prescribed agents for arthritic patients, although gastric effects limit their long-term use. Considering the reported gastric safety of hydrogen sulfide (H2S)-releasing NSAIDs, in addition to the anti-inflammatory effects of H2S administration to rats with synovitis, we decided to evaluate the effects of the H2S-releasing naproxen derivative ATB-346 in this animal model. Methods Male Wistar rats were anesthetized with inhalatory halothane and pre-treated with equimolar oral doses of either naproxen (0.3, 1, 3 or 10 mg/kg) or ATB-346 (0.48, 1.6, 4.8, or 16 mg/kg) 30 min before the i.art. injection of 7.5 mg of carrageenan (CGN) into the right knee joint cavity. Joint swelling and pain score were assessed after 1, 3 and 5 h, and tactile allodynia after 2 and 4 h. After the last measurement, the joint cavity lavages were performed for counting of the recruited leukocytes. The drugs (at the highest doses) were also tested for their gastric effects by evaluating macroscopical damage score and neutrophil recruitment (measured as myeloperoxidase – MPO activity) in the stomachs 5 h after administration of the drugs. In addition, the serum naproxen pharmacokinetic profiles of both compounds, administered at the highest equimolar doses, were obtained during the first 6 h after dosing. Results At the two highest tested doses, both naproxen and ATB-346 reduced edema and pain score (measured 3 and 5 h after CGN; P

New fluorinated and methoxylated di(hetero)arylethers and di(hetero)arylamines were prepared functionalizing the 7-position of the thieno[3,2-blpyridine, using copper (C-O) or palladium (C N) catalyzed couplings, respectively, of the 7-bromothieno[3,2-blpyridine, also prepared, with ortho, meta and para fluoro or methoxy phenols and anilines. The compounds obtained were evaluated for their growth inhibitory activity on the human tumor cell lines MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), HCI15 (colon carcinoma), HepG2 (hepatocellular carcinoma) and HeLa (cervical carcinoma). The most active compounds, a di(hetero)arylether with a methoxy group in the meta position relative to the ether function and two di(hetero)arylamines with a methoxy group either in the ortho or in the meta position relative to the NH, were further tested at their GI(50) concentrations on NCI-H460 cells causing pronounced alterations in the cell cycle profile and a strong and significant increase in the programmed death of these cells. The fluorinated and the other methoxylated compounds did not show important activity, presenting high GI(50) values in all the cell lines tested. Furthermore, the hepatotoxicity of the compounds was assessed using porcine liver primary cells (PLP2), established by some of us. Results showed that one of the most active compounds was not toxic to the non-tumor cells at their GI(50) concentrations showing to be the most promising as antitumoral., The authors would like to thank to the Foundation for the Science and Technology (PCT Portugal) for financial support through the NMR Portuguese network (Bruker 400 Avance III-Univ Minho); to FCT and FEDER-COMPETE/QREN/EU for financial support through the research unities PEst-C/QUI/UI686/2011 and PEst-OE/AGR/UI0690/2011, the research project PTDC/QUI-QUI/111060/2009 and the post-Doctoral grants attributed to R.C.C. (SFRH/BPD/68344/2010) and R.T.L. (SRH/BPD/68787/2010). IPATIMUP is an Associate Laboratory of the Portuguese Ministry of Science, Technology and Higher Education and is partially supported by FCT.

Several edible mushrooms extracts are known to have tumor cell growth inhibitory potential. The objective of this work was to study this potential in extracts of Suillus luteus collected from the Northeast of Portugal. Various extracts were prepared and their effect on tumor cell growth was studied with the SRB assay in four human tumor cell lines: MCF-7 (breast), NCI-H460 (non-small cell lung cancer), AGS (gastric) and HCT-15 (colon). The methanolic extract of S. luteus was the most potent extract. This extract was slightly more potent in the HCT-15 cells (with mutant p53, GI(50) = 17.8 +/- 1.6 mu g/mL) than in the other cell lines tested, which suggested that its effect was not p53-dependent. Indeed, in HCT-15 cells, an increase in the levels of p53 was detected but no alterations in some of the proteins transactivated by p53 (e.g. p21 or Box) were found. The extract caused an increase in the cellular levels of p-H2A.X, which is suggestive of DNA damage. Growth inhibition in these cells was mostly due to inhibition of cell proliferation and an increase in the % of cell in the G1 phase of the cell cycle. An increase in cell death was also found, even though to very low levels. In addition, this extract was not cytotoxic to primary cultures of porcine hepatocytes (GI(50) > 400 mu g/mL). Together, these results indicate that the S. luteus methanolic extract may be an interesting source of compounds that inhibit the proliferation of tumor cells but further studies should be carried out in order to understand its potential., The authors are grateful to Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) and COMPETE/QREN/EU for the financial support to this work (research project PTDC/AGR-ALI/110062/2009) and to CIMO (strategic project PEst-OE/AGR/U10690/2011). They also thank the University of Porto and Santander Totta for financial support. J.A. Vaz thanks FCT, POPH-QREN and FSE for her grant (BD/43653/2008). G.M. Almeida is supported by FCT and the European Social Fund. IPATIMUP is an Associate Laboratory of the Portuguese Ministry of Science, Technology and Higher Education and is partially supported by FCT.

Controversy exists as to whether H 2 S has a direct protective or deleterious effect on arthritis. Although we have evidence from our previous study that exogenous H 2 S delivered to the knee joint can produce a significant anti-inflammatory and anti-nociceptive effect against carrageenan-induced joint synovitis [1] , the mechanisms involved are unknown. To investigate this, synovitis was induced in Wistar rats (previously treated with Lawesson reagent [LR], a classical H 2 S donor) by intra-articular injection of carrageenan into the knee joint in the presence or absence of treatment with glibenclamide (antagonist at the sulfonylurea receptor 1 (SUR1) regulatory sub-unit of ATP-sensitive K + (K ATP ) channels), capsazepine (transient receptor potential vanilloid 1 antagonist TRPV1), and verapamil (L-type Ca 2+ channel blocker). Both nociceptive and inflammatory parameters were assessed 4 h later. Animal procedures were approved by the local Ethics Committee and injections were performed under isoflurane anaesthesia. As expected, LR significantly attenuated the carrageenan (CGN)-induced nociceptive response of the ipsilateral hindpaw (impaired gait and secondary tactile allodynia) and related inflammatory process. Suppression of CGN-induced synovitis formation by H 2 S donor was not reversed by the blockade of K + (K ATP ), TRPV1 or L-type Ca 2+ channels. However, CGN-induced knee oedema and associated nociception was suppressed by glibenclamide, capsazepine or verapamil alone to the same extent as by LR. Compared with control group, determinants of oxidative stress (e.g. glutathione S-transferase (GST) and glutathione reductase (GR)) in the synovial membrane of rats with synovitis showed no differences among groups. These findings demonstrate that exogenous administration of H 2 S donor Lawesson reagent-induced protective effect against CGN-mediated synovitis and referred allodynia does not seem to require activation of both K ATP channels and L-type Ca 2+ or TRPV1 receptors in rats. Thus, the full details of the mechanisms of action of H 2 S donors in CGN-induced synovitis remain to be elucidated. Financial support : CAPES, CNPq, FAPESP.

A growing body of evidence suggests that hydrogen sulphide (H2S) plays a crucial role in both physiological and pathophysiological process, including heart failure, inflammatory lung and articular diseases, erectile dysfunction, diabetes, among others. Poor diabetes control in women (mean glycosylated hemoglobin level The aim of this study is to determine the effectiveness of the slow H2S-releasing donor GYY4137 in reducing itch behaviour and cutaneous inflammation in mouse dorsal skin. The animal protocols were approved by the local ICB-USP Ethics Committee. In order to produce itching behaviour, male BALB/c mice (25–30 g) were anaesthetised with isoflurano and i.d. injected with histamine (1 μmol site−1) alone or co-injected with GYY4137 (0.3–30 nmol site−1; 0.05 ml). Itching behaviour was estimated by measuring the number of scratching bouts over a 40 min period. In a separate set of experiments, animals were pre-treated (−40 min) with the ATP-sensitive K+ (KATP) channel blocker glibenclamide, and then i.d. injected with histamine and Na2S (3 nmol site−1). In addition, we investigated the presence of mRNA for the enzymes cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE) and 3-mercaptopyruvate sulfur transferase (3-MST) in the mouse naive skin via qualitative RT-PCR. Data are presented as mean ± SEM and were analyzed by ANOVA followed by the Dunnett test. Values of P The i.d. injection of histamine significantly increased the itching frequency as compared to its vehicle Tyrode. Increasing doses of GYY4137 (1–10 nmol site−1) dose-dependently reduced histamine-induced pruritus but failed to inhibit plasma extravasation evoked by histamine. Suppression of histamine-induced pruritus by the H2S donor was not reversed by glibenclamide. A marked mRNA expression for CBS and 3-MST, but not for CSE, was seen in the mouse naive skin. These findings indicate that low doses of GYY4137 in the skin decrease histamine-induced pruritus without affecting the associated local inflammation. This protective effect does not appear to be mediated by KATP channels activation. Financial support: FAPESP, CAPES and CNPq.

Chemical and physical changes are necessary to improve the transport properties of polymeric membranes. Cellulose fiber pulp from Pinus taeda was processed in knives and balls mills in order to reduce the dimensions of the fibers for later application in polysulfone (PSf) membranes. By adding cellulosic fibers in PSf membranes, a composite membrane with improved morphological properties, permeate flux and good resistance to pressure was obtained. The fibers as well as the PSf and PSf/cellulose fibers membranes were morphologically characterized by scanning electron microscopy. Tests of pure water permeate flux were performed with pressure up to 20 bar. The addition of 0.2% (wt) of cellulose fibers in the formation of composite membranes resulted in the elimination of macrovoids, causing an increase in pure water flux (50% ±10) when pressure was risen.

Mitochondria play a key role in adaptation during stressing situations. Cardiolipin, the main anionic phospholipid in mitochondrial membranes, is expected to be a determinant in this adaptive mechanism since it modulates the activity of most membrane proteins. Here, we used Saccharomyces cerevisiae subjected to conditions that affect mitochondrial metabolism as a model to determine the possible role of cardiolipin in stress adaptation. Interestingly, we found that thermal stress promotes a 30% increase in the cardiolipin content and modifies the physical state of mitochondrial membranes. These changes have effects on mtDNA stability, adapting cells to thermal stress. Conversely, this effect is cardiolipin-dependent since a cardiolipin synthase-null mutant strain is unable to adapt to thermal stress as observed by a 60% increase of cells lacking mtDNA (ρ0). Interestingly, we found that the loss of cardiolipin specifically affects the segregation of mtDNA to daughter cells, leading to a respiratory deficient phenotype after replication. We also provide evidence that mtDNA physically interacts with cardiolipin both in S. cerevisiae and in mammalian mitochondria. Overall, our results demonstrate that the mitochondrial lipid cardiolipin is a key determinant in the maintenance of mtDNA stability and segregation.