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Selenium is an important element in nutrition, showing great potential in the udder health of dairy goats and in the control of subclinical mastitis. However, there are few studies that evaluated the influence of selenium supplementation on subclinical mastitis in goats. The aim of this study was to evaluate the incidence of subclinical mastitis in dairy goats supplemented with organic selenium (Se yeast) in a semi-arid region. Sixteen Saanen × Toggenburg crossbred lactating goats were allocated randomly into two treatments: with and without addition of organic selenium (Se) to the concentrate. Milk samples were collected every 20 days from each udder half to determine the somatic cell count (SSC), chloride content, pH, electrical conductivity, microbiological isolation, composition, and selenium contents. The highest serum selenium concentrations in the blood of these goats occurred at 42 days of supplementation (P < 0.001). Goats which received organic selenium supplementation had higher serum selenium concentrations (P < 0.05). The milk composition variables did not differ (P > 0.05) between the tested treatments, teats, and collections. After 60 days of supplementation, a difference was observed (P < 0.05) between treatments for SSC, chloride content, and pH. Addition of organic selenium to the diet of dairy goats after 60 days of supplementation was promising in reducing the somatic cell count, consequently improving milk quality.

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This study evaluated the effect of a mouthwash containing 0.075% cetylpyridinium chloride and 0.28% zinc lactate (CPC + Zn) in a multispecies biofilm model. A 7-days 33-species biofilm, formed on Calgary device, was 1-min treated with: 0.12% chlorhexidine (CHX), culture medium (negative control), 0.075% cetylpyridinium chloride (CPC) or CPC + Zn, 2x/day, from day 3 until day 6. The metabolic activity and the microbial composition were evaluated by colorimetric method and checkerboard DNA-DNA hybridization, respectively. The three antimicrobials (CPC, CPC + Zn and CHX) reduced metabolic activity, total biofilm count and several species counts, including Porphyromonas gingivalis, Fusobacterium nucleatum, Parvimonas micra, Campylobacter gracilis and Streptococcus mutans. However, only CPC + Zn reduced counts of the pathogen Prevotella intermedia and did not interfere with the levels of some beneficial species in relation to the negative control. The treatment of multispecies subgingival biofilm with CPC + Zn was effective in controlling periodontal pathogens and favored the colonization of health-associated bacterial species.

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Mercury is considered a risk factor for the development of hypertension and other cardiovascular diseases. We investigated whether the effects of mercury exposure on haemodynamic parameters of young Wistar rats and prehypertensive SHRs might alter the time course of hypertension development. Young (4 weeks) male Wistar rats and SHRs were randomly assigned to four groups: untreated Wistar rats (Wistar Ct), Wistar rats exposed to mercury chloride for 30 days (Wistar Hg), untreated SHRs (SHR Ct) and SHRs exposed to mercury chloride (SHR Hg) for 30 days. Non-invasive and invasive arterial pressures were measured to investigate pressure reactivity; nitrite/nitrate levels, ACE activity, and lipid peroxidation were measured in plasma. The systolic blood pressure (SBP) of the Wistar rat groups did not change but increased in the SHRs from the second week to the last week. Hg exposure accelerated the increase in the SBP of SHRs. L-NAME administration increased SBP and diastolic blood pressure (DBP) in all groups, but this increase was smaller in SHRs exposed to Hg. A decrease in plasma nitrite and nitrate levels in the SHR Hg group suggested that mercury reduced NO bioavailability. Tempol-reduced blood pressure suggesting that the superoxide anion played a role in the marked increase in this parameter. These findings provide evidence that Hg exposure might activate mechanisms to accelerate hypertension development, including a reduction in NO bioavailability. Therefore, predisposed individuals under mercury exposure are at greater risk from an enhanced development of hypertension.

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Herein a systematic series of four [AuLL']n+ n = 0, +1 complexes, where L = 1,3-bis(mesityl)imidazole-2-ylidene (IMes), or triphenylphosphine (PPh3), and L' = chloride, or 4-dimethylaminopyridine (DMAP), had their in vitro antiviral activity assessed against Chikungunya virus (CHIKV). The PPh3 derivatives inhibited viral replication by 99%, whereas the IMes derivatives about 50%. The lipophilicity of the PPh3 derivatives is higher than the IMes-bearing compounds, which can be related to their more prominent antiviral activities. The dissociation of DMAP is faster than chloride in solution for both IMes and PPh3 derivatives; however, it does not significantly affect their in vitro activities, showing a higher dependence on the nature of L rather than L' towards their antiviral effects. All complexes bind to N-acetyl-L-cysteine, with the Ph3P-bearing complexes coordinating at a faster rate to this amino acid. The binding constants to bovine serum albumin are in the order of 104, slightly higher for the DMAP complexes in both PPh3 and IMes derivatives. Mechanistic investigations of the PPh3 complexes showed a ubiquitous protective effect of the compounds in the pretreatment, early stages, and post-entry assays. The most significant inhibition was observed in post-entry activity, in which the complexes blocked viral replication in 99%, followed by up to 95% inhibition of the early stages of infection. Pretreatment assays showed a 92% and 80% replication decrease for the chloride and DMAP derivatives, respectively. dsRNA binding assays showed a significant interaction of the compounds with dsRNA, an essential biomolecule to viral replication.

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Chagas disease is a disease that is emerging in North America and Europe countries. Benznidazole is the main drug available, but it has high toxicity and low efficacy in the chronic phase. In this way, researching new antichagasic agents is necessary. Thus, the aim of this study is to evaluate the effect of novel chalcones and the influence of chlorine substitutions on Trypanosoma cruzi and host cells. Unsubstituted (1), 4-chlorine substituted (2) and 2,4-chlorine substituted (3) chalcones were synthesized by Claisen-Schmidt condensation, characterized, and electrical distribution was assessed by Density Fuctional Theory (DFT). The host cells toxicity (LLC-MK2) was performed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) reduction assay. The effect on epimastigote (24, 48 and 72h), trypomastigote (24h) and amastigotes (24 h) was evaluated. Flow cytometry assays were performed with 7-Aminoactinomycin D (7-AAD) and Annexin-PE, Dichlorofluorescein diaceteate (DCFH-DA) and Rhodamine123 (Rho123). Finally, molecular docking predicted interactions between chalcones and cruzain (TcCr) and trypanothione reductase (TcTR). The toxicity on host cells was reduced almost twenty times on chlorine substituted molecules. On epimastigote and trypomastigote forms, all substances presented similar effects. After treatment with molecule 3, it was observed a decrease in infected cells and intracellular amastigotes. Their effect is related to necrotic events, increase of cytoplasmic Reactive Oxygen Species (ROS) and mitochondrial dysfunction. Also, this effect might be associated with involvement of TcCr and TcTR enzymes. Therefore, the results showed that chlorine substitution on chalcones reduces the host cell's toxicity without compromising the effect on Trypanosoma cruzi Y strain forms, and it occurs over membrane damage, oxidative stress and possible interactions with TcCr and TcTR.

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Skeletal muscle has the intrinsic ability to self-repair through a multifactorial process, but many aspects of its cellular and molecular mechanisms are not fully understood. There is increasing evidence that some members of the mammalian ß-galactoside-binding protein family (galectins) are involved in the muscular repair process (MRP), including galectin-3 (Gal-3). However, there are many questions about the role of this protein on muscle self-repair. Here, we demonstrate that endogenous Gal-3 is required for: (i) muscle repair in vivo by using a chloride-barium myolesion mouse model and (ii) mouse primary myoblasts myogenic programming. Injured muscle from Gal-3 knockout mice (GAL3KO) showed persistent inflammation associated with compromised muscle repair and the formation of fibrotic tissue on the lesion site. In GAL3KO mice, osteopontin expression remained high even after 7 and 14 d of the myolesion, while Myoblast differentiation transcription factor (MyoD) and myogenin had decreased their expression. In GAL3KO mouse primary myoblast cell culture, Paired Box 7 (Pax7) detection seems to sustain even when cells are stimulated to differentiation and MyoD expression is drastically reduced. The detection and temporal expression levels of these transcriptional factors appear to be altered in Gal-3-deficient myoblast. Gal-3 expression in wild-type mice for GAL3KO states, both in vivo and in vitro, in sarcoplasm/cytoplasm and myonuclei; as differentiation proceeds, Gal-3 expression is drastically reduced, and its location is confined to the sarcolemma/plasma cell membrane. We also observed a change in the temporal-spatial profile of Gal-3 expression and muscle transcription factors levels during the myolesion. Overall, these results demonstrate that endogenous Gal-3 is required for the skeletal muscle repair process.

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OBJECTIVES: To evaluate the in vitro photodynamic activity of aluminum phthalocyanine tetrasulfonate chloride (AlPcClS4) on promastigotes and amastigotes of Leishmania (Viannia) peruviana and Leishmania (Viannia) braziliensis. MATERIALS AND METHODS: The activity of photodynamic therapy using AlPcClS4 on Leishmania promastigote and amastigotes was determined by the Methyl Thiazole Tetrazolium (MTT) colorimetric method and quantitative PCR, respectively. RESULTS: Photodynamic treatment showed an inhibitory effect on promastigotes, particularly on Leishmania (V.) peruviana, to a lesser extent on Leishmania (V.) braziliensis and also on intracellular forms of both species. At 24 hours post-radiation, using concentrations of 200 µM and 350 µM, the inhibitory effect on Leishmania (V.) peruviana was 72.9% and 73.9% respectively; at 96 hours the inhibitory effect was of 78.8% and 80.6%, respectively. Regarding intracellular forms, the inhibitory effect on Leishmania (V.) peruviana amastigotes was 57.8% at 72 hours post-treatment, using a concentration of 200 µM. The IC50 was 56.5, 50, 44 and 39.7 µM, at 24, 48, 72 and 96 hours post-radiation, respectively. CONCLUSIONS: Photodynamic therapy using AlPcClS4 against Leishmania species showed encouraging results, mainly on Leishmania (V.) peruviana, suggesting a potential use as an alternative or complement to the usual treatment of tegumentary leishmaniasis. However, new trials are still required to determine the selectivity index for the intracellular form of the parasite, and to develop methods to facilitate the efficient entry of the molecule into the host cell and the parasite.

OBJETIVOS: Evaluar la actividad fotodinámica in vitro de la ftalocianina de aluminio tetrasulfonada clorada (AlPcClS4) sobre promastigotes y amastigotes de Leishmania (Viannia) peruviana y Leishmania (Viannia) braziliensis. MATERIALES Y MÉTODOS: La actividad del tratamiento fotodinámico empleando AlPcClS4 sobre promastigotes y amastigotes de Leishmania fue determinada mediante el método colorimétrico Metil Tiazol Tetrazolium (MTT) y PCR cuantitativo, respectivamente. RESULTADOS: El tratamiento fotodinámico presentó un efecto inhibitorio sobre promastigotes, principalmente sobre Leishmania (V.) peruviana, en menor proporción sobre Leishmania (V.) braziliensis y sobre las formas intracelulares de ambas especies. En Leishmania (V.) peruviana, a las 24 horas posirradiación a 200 µM y 350 µM el efecto inhibitorio fue del 72,9% y 73,9%, respectivamente y a las 96 horas fue del 78,8% y 80,6%, respectivamente. En las formas intracelulares, empleando 200 µM y evaluado a las 72 horas postratamiento, se observó una inhibición del 57,8% de amastigotes de Leishmania (V.) peruviana. El IC50 fue del 56,5; 50; 44; y 39,7 µM, que corresponde a las 24, 48, 72 y 96 horas posirradiación, respectivamente. CONCLUSIONES: El tratamiento fotodinámico empleando AlPcClS4 frente a las especies de Leishmania presentó resultados alentadores principalmente sobre Leishmania (V.) peruviana, lo cual sugiere su potencial uso como alternativa o complemento del tratamiento convencional de la leishmaniasis tegumentaria. Sin embargo, aún se requiere continuar con nuevos ensayos para determinar el índice de selectividad sobre el parásito en su forma intracelular, y desarrollar estrategias que faciliten el ingreso eficiente de la molécula hacia la célula hospedera y al parásito.

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PURPOSE: To develop a new wound dressing composed of alginate and Aloe vera gel and cross-linked with zinc ions. METHODS: The aloe-alginate film was characterized using scanning electron microscopy (SEM), swelling profile, mechanical properties, polysaccharide content and X-ray diffraction (XRD). Thirty Wistar rats were divided in two groups a) treated with aloe-alginate film and b) control (treated with sterile gauze). Wound contraction measurements and hystological analysis were performed on 7th, 14th and 21st days after wound surgery. RESULTS: The aloe-alginate film presented adequated mechanical resistance and malleability for application as wound dressing. There was no statistical difference in wound contraction between two groups. Histological assay demonstrated that aloe-alginate film presented anti-inflammatory activity, stimulated angiogenesis on proliferative phase and a more significant increased in collagen type I fibers and decreased type III fibers which promoted a mature scar formation when compared to control. CONCLUSIONS: The aloe-alginate film showed adequate physicochemical characteristics for wound dressing applications. The in vivo assay demonstrated that aloe-alginate film enhanced the healing process of incisional skin wounds.

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Synthesis of four compounds belonging to mesoionic class, (E)-3-phenyl-5-(phenylamino)-2-styryl-1,3,4-thiadiazol-3-ium chloride derivatives (5a-d) and their biological evaluation against MT2 and C92 cell lines infected with human T-cell lymphotropic virus type-1 (HTLV-1), which causes adult T-cell leukemia/lymphoma (ATLL), and non-infected cell lines (Jurkat) are reported. The compounds were obtained by convergent synthesis under microwave irradiation and the cytotoxicity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Results showed IC50 values of all compounds in the range of 1.51-7.70 M in HTLV-1-infected and non-infected cells. Furthermore, it was observed that 5b could induce necrosis after 24 h for Jurkat and MT2 cell lines. The experimental (fluorimetric method) and theoretical (molecular docking) results suggested that the mechanism of action for 5b could be related to its capacity to intercalate into DNA. Moreover, the preliminary pharmacokinetic profile of the studied compounds (5a-d) was obtained through human serum albumin (HSA) binding affinity using multiple spectroscopic techniques (circular dichroism, steady-state and time-resolved fluorescence), zeta potential and molecular docking calculations. The interaction HSA:5a-d is spontaneous and moderate (Ka ~ 104 M-1) via a ground-state association, without significantly perturbing both the secondary and surface structures of the albumin in the subdomain IIA (site I), indicating feasible biodistribution in the human bloodstream.

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We previously showed that microwave assisted synthesis is the best method for the synthesis of naphthoquinone amino acid and chloride-naphthoquinone amino acid derivatives by a complete evaluation of reaction conditions such as stoichiometry, bases, and pH influence. Following the same strategy, we synthesized chloride and non-chloride tyrosine, valine, and tryptophan-naphthoquinones achieving 85-95%, 80-92%, and 91-95% yields, respectively. The cyclic voltammetry profiles showed that both series of naphthoquinone amino acid derivatives mainly display one redox reaction process. Overall, chloride naphthoquinone amino acid derivatives exhibited redox potential values (E1/2) more positive than non-chloride compounds. The six newly synthesized compounds were tested in HPV positive and negative as well as in immortal and tumorigenic cell lines to observe the effects in different cellular context simulating precancerous and cancerous status. A dose-response was achieved to determine the IC50 of six newly synthesized compounds in SiHa (Tumorigenic and HPV16 positive), CaLo (Tumorigenic and HPV18 positive), C33-A (Tumorigenic and HPV negative) and HaCaT (Keratinocytes immortal HPV negative) cell lines. Non-chloride tryptophan-naphthoquinone (3c) and chloride tyrosine-naphthoquine (4a) effects were more potent in tumorigenic SiHa, CaLo, and C33-A cells with respect to non-tumorigenic HaCaT cells. Interestingly, there seems to be a differential effect in non-chloride and chloride naphthoquinone amino acid derivatives in tumorigenic versus non tumorigenic cells. Considering all naphthoquinone amino acid derivatives that our group synthesized, it seems that hydrophobic and aromatic amino acids have the greatest effect on cell proliferation inhibition. These results show promising compounds for cervical cancer treatment.

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