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Skin cancer is one of the cancers that registers the highest number of new cases annually. Among all forms of skin cancer, melanoma is the most invasive and deadliest. The resistance of this form of cancer to conventional treatments has led to the employment of alternative/complementary therapeutic approaches. Photodynamic therapy (PDT) appears to be a promising alternative to overcome the resistance of melanoma to conventional therapies. PDT is a non-invasive therapeutic procedure in which highly reactive oxygen species (ROS) are generated upon excitation of a photosensitizer (PS) when subjected to visible light of an adequate wavelength, resulting in the death of cancer cells. In this work, inspired by the efficacy of tetrapyrrolic macrocycles to act as PS against tumor cells, we report the photophysical characterization and biological assays of isobacteriochlorins and their corresponding chlorins and porphyrins against melanoma cancer cells through a photodynamic process. The non-tumoral L929 fibroblast murine cell line was used as the control. The results show that the choice of adequate tetrapyrrolic macrocycle-based PS can be modulated to improve the performance of PDT.

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The aim of this study was to investigate the effects of inorganic mercury (Hg2+) exposure on biochemical parameters of dams and their offspring exposed to metal in drinking water. Female Wistar rats were exposed to 0, 10, and 50 µg Hg2+/mL (as HgCl2) for 42 days corresponding to gestational (21 days) and lactational (21 days) periods. The offspring were sacrificed on postnatal days 10, 20, 30, and 40. Dams exposed to Hg2+ presented a decrease in water intake in gestation [total: F(2,19) = 15.84; p ≤ 0.0001; daily: F(2,21) = 12.71; p = 0.0002] and lactation [total: F(2,19) = 4.619; p = 0.024; daily: F(2,21) = 5.309; p = 0.0136] without alteration in food intake. Dams exposed to 50 µg Hg2+/mL had an increase in kidney total [F(2,21) = 8.081; p = 0.0025] and relative [F(2,21) = 14.11; p = 0.0001] weight without changes in biochemical markers of nephrotoxicity. Moreover, dams had an increase in hepatic [F(2,10) = 3.847; p = 0.0577] and renal [F(2,11) = 6.267; p = 0.0152] metallothionein content concomitantly with an increase in renal Hg levels after Hg2+ exposure. Regarding offspring, the exposure to Hg2+in utero and breast milk increased the relative liver [F(2,18) = 5.33; p = 0.0152] and kidney [F(2,18) = 3.819; p = 0.0415] weight only on the postnatal day 40. In conclusion, dams were able to handle the Hg2+ avoiding the classic Hg2+ toxic effects as well as protecting the offspring. We suggest that this protection is related to the hepatic and renal metallothionein content increase.

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Melanoma is the most dangerous form of skin cancer, with an abrupt growth of its incidence over the last years. It is extremely resistant to traditional treatments such as chemotherapy and radiotherapy, but therapies for this cancer are gaining attention. Photodynamic therapy (PDT) is considered an effective modality to treat several types of skin cancers and can offer the possibility to treat one of the most aggressive ones: melanoma. In this work, the effect of PDT on a melanotic cell line (B16F10 cells) was assessed by exposing cultured cells to 5,10,15-tris(pentafluorophenyl)-20-(4-pyridyl)porphyrin (PS1) and to its chlorin (PS2) and isobacteriochlorin (PS3) corresponding derivatives and red LED light (λ = 660 ± 20 nm). The PDT effect in the cells' viability was measured using the MTT assay. The cell apoptosis was quantified by flow cytometry, and the subcellular localization of the photosensitizer was determined by fluorescence microscopy. In addition, the ability of PS2 to generate superoxide radicals was qualitatively assessed by tyrosine nitration. The results show that the efficiency of the PDT process is dependent on the structure of the PS and on their ability to produce singlet oxygen. Besides that, the photoactivation efficiency is highly dependent on the cellular sublocalization of the PS and on its cellular uptake and singlet oxygen production. We also found that the resistant cell line B16F10 has distinctive chlorin, isobacteriochlorin, or porphyrin-specific resistance profiles. Furthermore, it is shown that the highly fluorescent chlorin derivative PS2 can also be considered in imaging diagnostics.

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Hatchery efficiency is based on hatchability and the number of salable chicks. The hatchery sector has been seeking new alternatives to optimize production rates, including the use of different systems (multistage [MS] or single-stage [SS] machines) to improve incubation conditions. The present study aimed to compare results for hatchability, chick quality, and broiler performance of chicks from 2 incubator systems-MS and SS. The experimental design for hatchability, hatch window, egg weight loss, and chick performance variables was completely randomized with 2 treatments (MS and SS). Performance variables were analyzed as a 2 x 2 factorial arrangement (incubator type x chick sex). Egg weight loss between incubation and transfer was higher for eggs incubated in MS (P < 0.05). Hatchability was higher for eggs incubated in SS (P < 0.05), and chicks in SS had a longer hatch window (P < 0.05). Embryo diagnosis revealed higher final mortality for embryos incubated in MS (P < 0.05), as well as higher percentages of alive and dead pipped and cracked eggs (P < 0.05). Physical quality was better for chicks from SS (P < 0.05). There was no interaction between the studied factors for performance results (P > 0.05). Incubator type did not affect broiler performance for any of the studied ages (P > 0.05), whereas male broilers had better performance than females (P < 0.05). The SS incubation system proved better than the MS system at meeting embryo requirements during embryo development, with better hatching rates and chick quality, although performance variables were not influenced by incubation type.

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The present study aimed to ascertain the effects of slow-growing breeder age on embryo development, incubation results, and chick quality and of the interaction between breeder age and hatching time on initial performance. A total of 630 hatching eggs obtained from a commercial flock of slow-growing broiler breeders (Isa Label Naked Neck) were evaluated in 2 experiments. The first experiment evaluated embryo development and hatching results for broiler breeder age treatments of 38 and 51 wk, whereas the second experiment evaluated broiler chick performance. For the second experiment, chicks were distributed in a 2 x 2 factorial randomized block (sex) experimental design consisting of 2 breeder ages (31 or 58 wk) and 2 hatching times (479-485 and 491-497 h). At 18 d of embryonic development, embryos of 51-wk-old breeders were larger than those of 38-wk-old breeders (P < 0.05), whereas yolk-free chick weight was similar (P > 0.05). Embryo organ weight was similar for the 2 breeder ages (P > 0.05); however, there was greater development of intestinal villi for embryos of the 51-wk-old breeders. There were no differences between breeder ages in hatchability and chick quality score (P > 0.05). Yolk-free chick weight at pulling was greater (P < 0.05) for chicks from 51-wk-old breeders. Hatching time did not affect performance from 1 to 7 d (P > 0.05); however, chicks hatching at 491-497 h had better performance from 1 to 28 d than did chicks hatching at 479-485 h (P < 0.05). In conclusion, the age of slow-growing breeders affects embryo villi development and chick weight but does not improve incubation results or chick quality. Chicks hatching later (491-497 h) had better performance results than chicks hatching earlier (479-485 h).

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Alicyclobacillus acidoterrestris is a cause of major concern for the orange juice industry due to its thermal and chemical resistance, as well as its spoilage potential. A. acidoterrestris spoilage of orange juice is due to off-flavor taints from guaiacol production and some halophenols. The present study aimed to evaluate the effectiveness of antimicrobial Photodynamic Treatment (aPDT) as an emerging technology to inactivate the spores of A. acidoterrestris. The aPDT efficiency towards A. acidoterrestris was evaluated using as photosensitizers the tetracationic porphyrin (Tetra-Py+-Me) and the phenothiazinium dye new methylene blue (NMB) in combination with white light-emitting diode (LED; 400-740 nm; 65-140 mW/cm2). The spores of A. acidoterrestris were cultured on YSG agar plates (pH 3.7 ± 0.1) at 45 °C for 28 days and submitted to the aPDT with Tetra-Py+-Me and NMB at 10 µM in phosphate-buffered saline (PBS) in combination with white light (140 mW/cm2). The use of Tetra-Py+-Me at 10 µM resulted in a 7.3 ± 0.04 log reduction of the viability of A. acidoterrestris spores. No reductions in the viability of this bacterium were observed with NMB at 10 µM. Then, the aPDT with Tetra-Py+-Me and NMB at 10 µM in orange juice (UHT; pH 3.9; 11°Brix) alone and combined with potassium iodide (KI) was evaluated. The presence of KI was able to potentiate the aPDT process in orange juice, promoting the inactivation of 5 log CFU/mL of A. acidoterrestris spores after 10 h of white light exposition (140 mW/cm2). However, in the absence of KI, both photosensitizers did not promote a significant reduction in the spore viability. The inactivation of A. acidoterrestris spores artificially inoculated in orange peels (105 spores/mL) was also assessed using Tetra-Py+-Me at 10 and 50 µM in the presence and absence of KI in combination with white light (65 mW/cm2). No significant reductions were observed (p < .05) when Tetra-Py+-Me was used at 10 µM, however at the highest concentration (50 µM) a significant spore reduction (≈ 2.8 log CFU/mL reductions) in orange peels was observed after 6 h of sunlight exposition (65 mW/cm2). Although the color, total phenolic content (TPC), and antioxidant capacity of orange juice and peel (only color evaluation) seem to have been affected by light exposition, the impact on the visual and nutritional characteristics of the products remains inconclusive so far. Besides that, the results found suggest that aPDT can be a potential method for the reduction of A. acidoterrestris spores on orange groves.

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This study evaluated the toxic effects of inorganic mercury (Hg) in pregnant and lactating rats, as well as the possible protective effect of zinc (Zn) and N-acetylcysteine (NAC). Pregnant and lactating rats were pre-treated with ZnCl2 (27 mg/kg) and/or NAC (5 mg/kg) and after 24 h, they were exposed to HgCl2 (10 mg/kg). Animals were sacrificed 24 h after Hg exposure, and biochemical tests and metal determination were performed. Regarding pregnant rats, Hg exposure caused kidney, blood, and placenta δ-aminolevulinic acid dehydratase (δ-ALA-D) activity inhibition, and the pre-treatments showed a tendency of protection. Moreover, all the animals exposed to Hg presented high Hg levels in the kidney, liver, and placenta when compared with control group. Pregnant rats pre-exposed to Zn (Zn-Hg and Zn/NAC-Hg groups) presented an increase in hepatic metallothionein levels. Therefore, lactating rats exposed to Hg presented renal and blood δ-ALA-D inhibition; the pre-treatments showed a tendency to prevent the renal δ-ALA-D inhibition and prevented the blood δ-ALA-D inhibition caused by Hg. Lactating rats exposed to Hg presented high Hg levels in the kidney and liver. These results showed that 10 mg/kg of HgCl2 causes biochemistry alterations in pregnant and lactating rats, and Zn and NAC present promising results against these damages.

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Since few studies have addressed the embryonic development of Guinea fowl (Numida meleagris), the objective of the present study was to evaluate its embryonic development in the Cerrado region of Brazil and compare the results to published descriptions of the embryonic development of other domestic bird species. The commercialized weight for Guinea fowl eggs used in the experiment was found to be 37.57 g, while egg fertility was 92%. Embryo growth rate (%) was higher on the sixth day of incubation relative to other days. The heart began beating on the third day of development, while eye pigmentation and upper and lower limb buds appeared on the sixth day. The yolk sac was incorporated on the 24th day followed by chick external pipping and hatching on the 28th day. Comparisons revealed that the embryonic development of Guinea fowl exhibits both similarities to, and differences from, the embryonic development of other domestic birds. From three days of embryonic development, differences were observed among the compared species. Despite the same incubation period, Guinea fowl embryos develop faster than turkeys. All species begin internal pecking two days before hatching and internal pecking 24 h before hatching.(AU)

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Photodynamic therapy (PDT) is a modality of cancer treatment in which tumor cells are destroyed by reactive oxygen species (ROS) produced by photosensitizers following its activation with visible or near infrared light. The PDT success is dependent on different factors namely on the efficiency of the photosensitizer deliver and targeting ability. In this review a special attention will be given to the role of some drug delivery systems to improve the efficiency of tetrapyrrolic photosensitizers to this type of treatment.

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Phytochemical-analysis of the ethyl acetate extract of stem wood of Salvertia convallariodora A. St.-Hil. (Vochysiaceae), a Brazilian Cerrado species, led to the isolation and full characterization of three new non-aromatic B-ring flavanones (1-3) as well as the terpene mixture of sericic acid (4), 24-hydroxytormentic acid (5); 24-hydroxytormentic acid glucosyl ester (6), and sericoside (7), all identified for the first time from S. convallariodora. The structures of the new flavanones (1-3) were established from IR, LC-PDA-qTOF-MS, and NMR spectral data, including 2D NMR experiments.

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