Navegação Periódicos - Artigos por autor "SABINO, CAETANO P."

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  • IPEN-DOC 27584

    ANJOS, CAROLINA dos; SELLERA, FABIO P.; RIBEIRO, MARTHA S. ; BAPTISTA, MAURICIO S.; POGLIANI, FABIO C.; LINCOPAN, NILTON; SABINO, CAETANO P.. Antimicrobial blue light and photodynamic therapy inhibit clinically relevant β-lactamases with extended-spectrum (ESBL) and carbapenemase activity. Photodiagnosis and Photodynamic Therapy, v. 32, p. 1-4, 2020. DOI: 10.1016/j.pdpdt.2020.102086

    Abstract: Introduction. The production of β-lactamases by Gram-negative bacteria is among the most important factors of resistance to antibiotics, which has contributed to therapeutic failures that currently threaten human and veterinary medicine worldwide. Antimicrobial photodynamic therapy and antimicrobial blue light have a broad-spectrum antibacterial activity against multidrug-resistant and hypervirulent pathogens. Objective. To investigate the ability of antimicrobial blue light to inhibit the hydrolytic activity of clinically relevant β-lactamase enzymes (i.e., KPC, IMP, OXA, CTX-M, and SHV), with further comparison of the inhibitory effects of antimicrobial blue light with methylene blue-mediated antimicrobial photodynamic therapy. Methods. Blue LED light (λ = 410 ± 10 nm) alone or red LED light (λ = 660 ± 10 nm) in combination with methylene blue were used to inactivate, in vitro, suspensions of Klebsiella pneumoniae strains producing clinically important β-lactamase enzymes assigned to the A, B and D Ambler molecular classes. Furthermore, β-lactamase activity inhibition mediated by antimicrobial blue light and methylene blue-mediated antimicrobial photodynamic therapy was measured by using the chromogenic β-lactam substrate nitrocefin. Results. β-lactamase activities were effectively inactivated by both visible light-based approaches. In this regard, antimicrobial blue light and methylene blue-antimicrobial photodynamic therapy led to a significant reduction in the hydrolysis of nitrocefin (81–98 %). Conclusion. Sublethal doses of antimicrobial blue light and methylene blue-mediated antimicrobial photodynamic therapy are equally effective to inhibit clinically significant β-lactamases, including extended-spectrum β-lactamases and carbapenemases.

    Palavras-Chave: antimicrobial agents; methylene blue; antibiotics; lactams; inactivation; enzymes

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  • IPEN-DOC 19113

    KATO, ILKA T.; PRATES, RENATO A.; SABINO, CAETANO P.; FUCHS, BETH B.; TEGOS, GEORGE P.; MYLONAKIS, ELEFTHERIOS; HAMBLIN, MICHAEL R.; RIBEIRO, MARTHA S. . Antimicrobial photodynamic inactivation inhibits Candida albicans virulence factors and reduces In vivo pathogenicity. Antimicrobial Agents and Chemotherapy, v. 57, n. 1, p. 445-451, 2013.

    Palavras-Chave: candida; fungal diseases; antimicrobial agents; therapy; inactivation; photosensitivity; methylene blue; semiconductor lasers; semiconductor diodes; pathogens

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  • IPEN-DOC 20840

    TENORIO, DENISE P.L.A.; ANDRADE, CAMILA G.; CABRAL FILHO, PAULO E.; SABINO, CAETANO P. ; KATO, ILKA T. ; CARVALHO JUNIOR, LUIZ B.; ALVES JUNIOR, SEVERINO; RIBEIRO, MARTHA S. ; FONTES, ADRIANA; SANTOS, BEATE S.. CdTe quantum dots conjugated to concanavalin A as potential fluorescent molecular probes for saccharides detection in Candida albicans. Journal of Photochemistry and Photobiology B: Biology, v. 142, p. 237-243, 2015.

    Palavras-Chave: candida; diagnosis; concanavalin a; fluorescence; cadmium tellurides; quantum dots; saccharides

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  • IPEN-DOC 20928

    SELLERA, FABIO P.; BARBOSA, BRUNA S.; GARGANO, RONALDO G.; SABINO, CAETANO P. ; RIBEIRO, MARTHA S. ; AZEVEDO, MILTON R.; BENESI, FERNANDO J.; POGLIANI, FABIO C.. Cutaneous streptococcal abscess treated by photodynamic therapy. African Journal of Traditional Complementary and Alternative Medicines, v. 12, n. 2, p. 65-67, 2015.

    Palavras-Chave: therapy; skin diseases; sheep; streptococcus; infectivity; photosensitivity

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  • IPEN-DOC 25764

    SELLERA, FABIO P.; FERNANDES, MIRIAM R.; SABINO, CAETANO P.; FREITAS, LAURA M. de; SILVA, LUCIANO C.B.A. da; POGLIANI, FABIO C.; RIBEIRO, MARTHA S. ; HAMBLIN, MICHAEL R.; LINCOPAN, NILTON. Effective treatment and decolonization of a dog infected with carbapenemase (VIM-2)-producing Pseudomonas aeruginosa using probiotic and photodynamic therapies. Veterinary Dermatology, v. 30, n. 2, p. 170-e52, 2019. DOI: 10.1111/vde.12714

    Abstract: Background – Carbapenem-resistant bacterial infections are a critical problem in veterinary medicine with limited treatment options. Objective – To describe effective probiotic and photodynamic therapy of a dog with gut colonization and ear infection caused by a hospital-associated lineage of carbapenemase (VIM-2)-producing Pseudomonas aeruginosa. Animals – A 5-year-old Lhasa apso dog presented with otitis externa. Methods and materials – Unilateral otitis externa caused by carbapenem-resistant P. aeruginosa was treated with antimicrobial photodynamic therapy (aPDT) using methylene blue as photosensitizer [wavelength 660 nm, fluence 140 J/cm2, 8 J and 80 s per point (six equidistant points), 100 mW, spot size 0.028 cm2 and fluence rate 3.5 W/cm2]. The isolated bacterial strain also was tested for susceptibility to in vitro aPDT where the survival fraction was quantified by colony forming unit counts after exposure to increasing light doses. For decolonization, probiotic supplements were orally administered (once daily) for 14 days. Effectiveness of probiotics and photodynamic therapy was evaluated by clinical and microbiological culture assays. Results – Complete resolution of clinical signs was achieved by Day 7 after aPDT. Samples collected immediately and after seven and 14 days following aPDT were negative for VIM-2-producing P. aeruginosa. Oral and rectal swabs collected on days 7, 14 and 21 after probiotic therapy, confirmed effective gastrointestinal decolonization. Conclusions and clinical importance – Combined use of aPDT and probiotics could be a promising therapeutic strategy for treatment of superficial infections produced by carbapenem-resistant bacteria, while avoiding recurrent infection due to intestinal bacterial carriage of these multidrug-resistant pathogens.

    Palavras-Chave: dogs; veterinary medicine; domestic animals; microorganisms; therapy; methylene blue; antimicrobial agents; bacterial diseases; photosensitivity

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  • IPEN-DOC 21672

    RIBEIRO, MARTHA S. ; NUNEZ, SILVIA C. ; SABINO, CAETANO P.; YOSHIMURA, TANIA M. ; SILVA, CAMILA R. ; NOGUEIRA, GESSE E.C. ; SUZUKI, HIDEO; GARCEZ, AGUINALDO S.. Exploring light-based technology for wound healing and appliance distribution. Journal of the Brazilian Chemical Society, v. 26, n. 12, p. 2583-2589, 2015.

    Palavras-Chave: comparative evaluations; therapy; methylene blue; healing; light emitting diodes; sterilization; mice; in vivo; lasers

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  • IPEN-DOC 27154

    SABINO, CAETANO P.; WAINWRIGHT, MARK; RIBEIRO, MARTHA S. ; SELLERA, FABIO P.; ANJOS, CAROLINA dos; BAPTISTA, MAURICIO da S.; LINCOPAN, NILTON. Global priority multidrug-resistant pathogens do not resist photodynamic therapy. Journal of Photochemistry and Photobiology B: Biology, v. 208, p. 1-9, 2020. DOI: 10.1016/j.jphotobiol.2020.111893

    Abstract: Microbial drug-resistance demands immediate implementation of novel therapeutic strategies. Antimicrobial photodynamic therapy (aPDT) combines the administration of a photosensitizer (PS) compound with low-irradiance light to induce photochemical reactions that yield reactive oxygen species (ROS). Since ROS react with nearly all biomolecules, aPDT offers a powerful multitarget method to avoid selection of drug-resistant strains. In this study, we assayed photodynamic inactivation under a standardized method, combining methylene blue (MB) as PS and red light, against global priority pathogens. The species tested include Acinetobacter baumannii, Klebsiella aerogenes, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterococcus faecium, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and Cryptococcus neoformans. Our strain collection presents resistance to all tested antimicrobials (> 50). All drug-resistant strains were compared to their drugsensitive counterparts. Regardless of resistance phenotype, MB-aPDT presented species-specific dose-response kinetics. More than 5log10 reduction was observed within less than 75 s of illumination for A. baumannii, E. coli, E. faecium, E. faecalis and S. aureus and within less than 7 min for K. aerogenes, K. pneumoniae, P. aeruginosa, C. albicans and C. neoformans. No signs of correlations in between drug-resistance profiles and aPDT sensitivity were observed. Therefore, MB-aPDT can provide effective therapeutic protocols for a very broad spectrum of pathogens. Hence, we believe that this study represents a very important step to bring aPDT closer to implementation into mainstream medical practices.

    Palavras-Chave: microbial drug resistance; photosensitivity; therapy; bacteria; antimicrobial agents; radiant flux density; light sources; inactivation

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  • IPEN-DOC 23521

    SUZUKI, LUIS C. ; KATO, ILKA T.; PRATES, RENATO A.; SABINO, CAETANO P. ; YOSHIMURA, TANIA M. ; SILVA, TAMIRES O.; RIBEIRO, MARTHA S. . Glucose modulates antimicrobial photodynamic inactivation ofCandida albicans in biofilms. Photodiagnosis and Photodynamic Therapy, v. 17, p. 173-179, 2017. DOI: 10.1016/j.pdpdt.2016.12.003

    Abstract: Candida albicans biofilm is a main cause of infections associated with medical devices such as catheters,contact lens and artificial joint prosthesis. The current treatment comprises antifungal chemotherapy thatpresents low success rates. Photodynamic inactivation (PDI) involves the combination of a photosensitiz-ing compound (PS) and light to generate oxidative stress that has demonstrated effective antimicrobialactivity against a broad-spectrum of pathogens, including C. albicans. This fungus senses glucose induc-ing an upregulation of membrane transporters that can facilitate PS uptake into the cell. The aim ofthis study was to evaluate the effects of glucose on methylene blue (MB) uptake and its influence onPDI efficiency when combined to a red LED with central wavelength at = 660 nm. C. albicans biofilmswere grown on hydrogel disks. Prior to PDI assays, MB uptake tests were performed with and withoutglucose-sensitization. In this system, the optimum PS administration was determined as 500 M of MBin contact with the biofilm during 30 min before irradiation. Irradiation was performed during 3, 6, 9, 12,15 and 18 min with irradiance of 127.3 mW/cm2. Our results showed that glucose was able to increaseMB uptake in C. albicans cells. In addition, PDI without glucose showed a higher viability reduction until6 min; after 9 min, glucose group demonstrated a significant decrease in cell viability when compared toglucose-free group. Taken together, our data suggest that glucose is capable to enhance MB uptake andmodulate photodynamic inactivation of C. albicans biofilm.

    Palavras-Chave: glucose; methylene blue; infectious diseases; inactivation; photosensitivity; yeasts

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  • IPEN-DOC 22388

    SELLERA, FABIO P.; SABINO, CAETANO P. ; RIBEIRO, MARTHA S. ; GARGANO, RONALDO G.; BENITES, NILSON R.; MELVILLE, PRISCILLA A.; POGLIANI, FABIO C.. In vitro photoinactivation of bovine mastitis related pathogens. Photodiagnosis and Photodynamic Therapy, v. 13, p. 276-281, 2016.

    Palavras-Chave: in vitro; cows; therapy; veterinary medicine; diagnosis; antibiotics; pathogens; cattle; methylene blue

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  • IPEN-DOC 26453

    SABINO, CAETANO P.; WAINWRIGHT, MARK; ANJOS, CAROLINA dos; SELLERA, FABIO P.; BAPTISTA, MAURICIO S.; LINCOPAN, NILTON; RIBEIRO, MARTHA S. . Inactivation kinetics and lethal dose analysis of antimicrobial blue light and photodynamic therapy. Photodiagnosis and Photodynamic Therapy, v. 28, p. 186-191, 2019. DOI: 10.1016/j.pdpdt.2019.08.022

    Abstract: Background: Antimicrobial Photodynamic therapy (A-PDT) has been used to treat infections. Currently, microbial inactivation data is reported presenting survival fraction averages and standard errors as discrete points instead of a continuous curve of inactivation kinetics. Standardization of this approach would allow clinical protocols to be introduced globally, instead of the piecemeal situation which currently applies. Methods: To this end, we used a power-law function to fit inactivation kinetics and directly report values of lethal doses (LD) and a tolerance factor (T) that informs if inactivation rate varies along the irradiation procedure. A deduced formula was also tested to predict LD for any given survival fraction value. We analyzed the photoantimicrobial effect caused by red light activation of methylene blue (MB-APDT) and by blue light (BL) activation of endogenous microbial pigments against 5 clinically relevant pathogens. Results: Following MB- APDT, Escherichia coli and Staphylococcus aureus cells become increasingly more tolerant to inactivation along the irradiation process (T < 1). Klebsiella pneumoniae presents opposite behavior, i.e., more inactivation is observed towards the end of the process (T > 1). P. aeruginosa and Candida albicans present constant inactivation rate (T˜1). In contrast, all bacterial species presented similar behavior during inactivation caused by BL, i.e., continuously becoming more sensitive to blue light exposure (T > 1). Conclusion: The power-law function successfully fit all experimental data. Our proposed method precisely predicted LD and T values. We expect that these analytical models may contribute to more standardized methods for comparisons of photodynamic inactivation efficiencies.

    Palavras-Chave: antimicrobial agents; therapy; chemotherapy; inactivation; lethal doses; light sources; data analysis; candida; methylene blue

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  • IPEN-DOC 27394

    SABINO, CAETANO P.; BALL, ANTHONY R.; BAPTISTA, MAURICIO S.; DAI, TIANHONG; HAMBLIN, MICHAEL R.; RIBEIRO, MARTHA S. ; SANTOS, ANA L.; SELLERA, FABIO P.; TEGOS, GEORGE P.; WAINWRIGHT, MARK. Light-based technologies for management of COVID-19 pandemic crisis. Journal of Photochemistry and Photobiology B: Biology, v. 212, p. 1-8, 2020. DOI: 10.1016/j.jphotobiol.2020.111999

    Abstract: The global dissemination of the novel coronavirus disease (COVID-19) has accelerated the need for the implementation of effective antimicrobial strategies to target the causative agent SARS-CoV-2. Light-based technologies have a demonstrable broad range of activity over standard chemotherapeutic antimicrobials and conventional disinfectants, negligible emergence of resistance, and the capability to modulate the host immune response. This perspective article identifies the benefits, challenges, and pitfalls of repurposing light-based strategies to combat the emergence of COVID-19 pandemic.

    Palavras-Chave: visible radiation; coronaviruses; ultraviolet radiation; antimicrobial agents; inactivation; photosensitivity; modulation; radiobiology; epidemiology; lasers; viruses

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  • IPEN-DOC 27824

    SELLERA, FABIO P.; BARBOSA, BRUNA S.; GARGANO, RONALDO G.; RISPOLI, VIVIAN F.P.; SABINO, CAETANO P.; OLLHOFF, RUDIGER D.; BAPTISTA, MAURICIO S.; RIBEIRO, MARTHA S. ; SA, LILIAN R.M. de; POGLIANI, FABIO C.. Methylene blue-mediated antimicrobial photodynamic therapy can be a novel non-antibiotic platform for bovine digital dermatitis. Photodiagnosis and Photodynamic Therapy, v. 34, p. 1-8, 2021. DOI: 10.1016/j.pdpdt.2021.102274

    Abstract: Background Bovine digital dermatitis (BDD) is one of the most important diseases that effect dairy cows. Methylene blue-mediated antimicrobial photodynamic therapy (MB-APDT) emerges as a promising technique to treat superficial infections in bovines. Methods Twenty BDD lesions located at the skin horn transition of the claw of pelvic limbs of 16 cows were treated by MB-APDT, using a red LED cluster (λ = 660 nm, irradiance =60 mW/cm2, exposure time = 40 s) combined with topical application of MB at 0.01 %; or by topical application of OXY (500 mg in 20 % solution). Each lesion was treated twice with an interval of 14 days. Lesions were weekly evaluated until day 28 by clinical analysis and by histological examination on days 0 and 28. Results Both treatments led to a similar reduction of lesions area. At day 28, three lesions treated by OXY did not present completely recovery, whereas no lesions were observed in MB-APDT group. OXY resulted in a slight increase in type I and III collagen levels, while MB-APDT led to a significant increase in the total area of both collagen types. An abundant number of spirochetes were histologically observed in all lesions before treatments. On the 28th day, five lesions treated by OXY still presented a slight number of spirochetes, whereas in MB-APDT group no spirochetes were evidenced. Conclusion Our findings suggest that MB-APDT is more effective than OXY and could be used in Veterinary practice to fight BDD.

    Palavras-Chave: methylene blue; antimicrobial agents; cattle; inactivation; photosensitivity; therapy; dermatitis; infectious diseases

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  • IPEN-DOC 29707

    ANJOS, CAROLINA dos; LEANSE, LEON G.; RIBEIRO, MARTHA S. ; SELLERA, FÁBIO P.; DROPA, MILENA; ARANA-CHAVEZ, VICTOR E.; LINCOPAN, NILTON; BAPTISTA, MAURÍCIO S.; POGLIANI, FABIO C.; DAI, TIANHONG; SABINO, CAETANO P.. New insights into the bacterial targets of antimicrobial blue light. Microbiology Spectrum, v. 11, n. 2, p. 1-13, 2023. DOI: 10.1128/spectrum.02833-22

    Abstract: Antimicrobial blue light (aBL) offers efficacy and safety in treating infections. However, the bacterial targets for aBL are still poorly understood and may be dependent on bacterial species. Here, we investigated the biological targets of bacterial killing by aBL (l = 410 nm) on three pathogens: Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Initially, we evaluated the killing kinetics of bacteria exposed to aBL and used this information to calculate the lethal doses (LD) responsible for killing 90 and 99.9% of bacteria. We also quantified endogenous porphyrins and assessed their spatial distribution. We then quantified and suppressed reactive oxygen species (ROS) production in bacteria to investigate their role in bacterial killing by aBL. We also assessed aBL-induced DNA damage, protein carbonylation, lipid peroxidation, and membrane permeability in bacteria. Our data showed that P. aeruginosa was more susceptible to aBL (LD99.9 = 54.7 J/cm2) relative to S. aureus (LD99.9 = 158.9 J/cm2) and E. coli (LD99.9 = 195 J/cm2). P. aeruginosa exhibited the highest concentration of endogenous porphyrins and level of ROS production relative to the other species. However, unlike other species, DNA degradation was not observed in P. aeruginosa. Sublethal doses of blue light (,LD90) could damage the cell membrane in Gram-negative species but not in S. aureus. In all bacteria, oxidative damage to bacterial DNA (except P. aeruginosa), proteins, and lipids occurred after high aBL exposures (.LD99.9). We conclude that the primary targets of aBL depend on the species, which are probably driven by variable antioxidant and DNA-repair mechanisms.

    Palavras-Chave: bacteria; germicides; chromosphere; lipids; oxidation; permeability; carbonylation; proteins; oxygen

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  • IPEN-DOC 23124

    YOSHIMURA, TANIA M. ; SABINO, CAETANO P.; RIBEIRO, MARTHA S. . Photobiomodulation reduces abdominal adipose tissue inflammatory infiltrate of diet-induced obese and hyperglycemic mice. Journal of Biophotonics, v. 9, n. 11-12, p. 1255-1262, 2016. DOI: 10.1002/jbio.201600088

    Abstract: Systemic inflammation is closely related to the development of insulin resistance and type-2 diabetes, since the activation of pro-inflammatory pathways leads to inhibition of insulin signaling. Although photobiomodulation (PBM) has proven beneficial effects on the treatment of inflammatory disorders, the phototherapeutic approach to manage the chronic inflammatory component of obesity and hyperglycemia had never been explored. In this work, obese and hyperglycemic mice are treated with PBM, and their body mass, glycemia and inflammatory infiltrate of abdominal adipose tissue are evaluated. During four weeks, irradiated animals are exposed to six irradiation sessions using an 843 nm LED (5.7 J cm(-2) at 19 mW cm(-2) per session). Non-irradiated control animals display inflammatory areas almost five times greater than the treated group (p < 0.001). This result on inflammatory infiltrate may have caused impacts on the significant lower blood glucose level from irradiated animals (p = 0.04), twenty-four hours after the last irradiation session. PBM on obese and hyperglycemic mice reduced five times the areas of inflammatory infiltrate within abdominal adipose tissue (a, b), whereas dense inflammatory regions were a common finding amidst non-irradiated animals (c). The asterisks on (c) correspond to the inflammatory infiltrate permeating adipocytes.

    Palavras-Chave: abdomen; adipose tissue; diabetes mellitus; metabolic diseases; therapy; inflammation; low dose irradiation

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  • IPEN-DOC 19116

    CHIBEBE JUNIOR, JOSE; FUCHS, BETH B.; SABINO, CAETANO P.; JUNQUEIRA, JULIANA C.; JORGE, ANTONIO O.C.; RIBEIRO, MARTHA S. ; GILMORE, MICHAEL S.; RICE, LOUIS B.; TEGOS, GEORGE P.; HAMBLIN, MICHAEL R.; MYLONAKIS, ELEFTHERIOS. Photodynamic and antibiotic therapy impair the pathogenesis of enterococcus faecium in a whole animal insect model. PLoS ONE, v. 8, n. 2, p. e55926, 2013.

    Palavras-Chave: bacteria; streptococcus; therapy; antibiotics; infectious diseases; antimicrobial agents; insects; animal tissues; biological models; photosensitivity

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  • IPEN-DOC 24332

    BAPTISTA, ALESSANDRA ; SABINO, CAETANO P. ; NUNEZ, SILVIA C.; MIYAKAWA, WALTER; MARTIN, AIRTON A.; RIBEIRO, MARTHA S. . Photodynamic damage predominates on different targets depending on cell growth phase of Candida albicans. Journal of Photochemistry & Photobiology, B: Biology, v. 177, p. 76-84, 2017. DOI: 10.1016/j.jphotobiol.2017.10.013

    Abstract: Photodynamic inactivation (PDI) has been reported to be effective to eradicate a wide variety of pathogens, including antimicrobial-resistant microorganisms. The aim of this study was to identify the potential molecular targets of PDI depending on growth phase of Candida albicans. Fungal cells in lag (6 h) and stationary (48 h) phases were submitted to PDI mediated by methylene blue (MB) combined with a (662 +/- 21) nm-LED, at 360 mW of optical power. Pre-irradiation time was 10 min and exposure times were 12 min, 15 min and 18 min delivering radiant exposures of 129.6 J/cm(2), 162 J/cm(2) and 194.4 J/cm(2), respectively, on a 24-well plate of about 2 cm(2) at an irradiance of 180 mW/cm(2). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force spectroscopy (AFS) and Fourier transform infrared spectroscopy (FT-IR) were employed to evaluate the photodynamic effect in young and old fungal cells following 15 min of irradiation. Morphological analysis revealed wrinkled and shrunk fungal cell membrane for both growth phases while extracellular polymeric substance (EPS) removal was only observed for old fungal cells. Damaged intracellular structures were more pronounced in young fungal cells. The surface nanostiffness of young fungal cells decreased after PDI but increased for old fungal cells. Cellular adhesion force was reduced for both growth phases. Fungal cells in lag phase predominantly showed degradation of nucleic acids and proteins, while fungal cells in stationary phase showed more pronounced degradation of polysaccharides and lipids. Taken together, our results indicate different molecular targets for fungal cells in lag and stationary growth phase following PDI.

    Palavras-Chave: fungal diseases; antibiotics; candida; adhesives; atomic force microscopy; spectroscopy; fourier transform spectrometers; flexibility; ultrastructural changes

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  • IPEN-DOC 20713

    SELLERA, FABIO P.; SABINO, CAETANO P. ; RIBEIRO, MARTHA S. ; FERNANDES, LORIE T.; POGLIANI, FABIO C.; TEIXEIRA, CARLOS R.; DUTRA, GUSTAVO H.P.; NASCIMENTO, CRISTIANE L.. Photodynamic therapy for pododermatitis in penguins. Zoo Biology, v. 33, n. 4, p. 353-356, 2014.

    Palavras-Chave: birds; dermatitis; antimicrobial agents; methylene blue; healing; wounds; photosensitivity; therapy

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  • IPEN-DOC 26678

    CABRAL, FERNANDA V. ; SABINO, CAETANO P.; DIMMER, JESICA A.; SAUTER, ISMAEL P. ; CORTEZ, MAURO J.; RIBEIRO, MARTHA S. . Preclinical investigation of methylene blue-mediated antimicrobial photodynamic therapy on Leishmania parasites using real-time bioluminescence. Photochemistry and Photobiology, v. 96, n. 3, p. 604-610, 2020. DOI: 10.1111/php.13188

    Abstract: Cutaneous leishmaniasis (CL) is a neglected disease that promotes destructive lesions. Difficulties in treatment are related to accessibility of drugs, resistance and toxicity. Antimicrobial photodynamic therapy (APDT) has been emerging as a promising treatment for CL. In this work, we evaluated methylene blue (MB)-mediated APDT (MB-APDT) on Leishmania amazonensis in vitro and in vivo by bioluminescence technique. In vitro, MB-APDT was performed using a red LED (k = 660 11 nm, 100 mW cm 2) and MB (100 μM) at different light doses. In vivo, mice were infected and 4 weeks later, randomly divided into three groups: control, APDT 1 (single session) and APDT 2 (two sessions of MB-APDT). MB was used at 100 μM and energy dose was established at 150 J cm 2. Parasite burden, lesion size and pain were evaluated weekly for 4 weeks. In vitro, lethal dose for 90% parasite inactivation was achieved at 48.8 J cm 2. In vivo, although APDT 1 and APDT 2 groups have showed similar parasite burden after 4 weeks, two sessions were clinically better, especially considering the inflammatory process associated to CL. Our findings reinforce MB-APDT as a costeffective treatment to combat CL.

    Palavras-Chave: antimicrobial agents; therapy; photosensitivity; methylene blue; parasites; bioluminescence; photochemistry; in vivo; in vitro; mice

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  • IPEN-DOC 28315

    SELLERA, FABIO P.; SABINO, CAETANO P.; CABRAL, FERNANDA V. ; RIBEIRO, MARTHA S. . A systematic scoping review of ultraviolet C (UVC) light systems for SARS-CoV-2 inactivation. Journal of Photochemistry and Photobiology, v. 8, p. 1-6, 2021. DOI: 10.1016/j.jpap.2021.100068

    Abstract: A significant amount of epidemiological evidence has underlined that human-to-human transmission due to close contacts is considered the main pathway of transmission, however since the SARS-CoV-2 can also survive in aerosols, water, and surfaces, the development and implementation of effective decontamination strategies are urgently required. In this regard, ultraviolet germicidal irradiation (UVGI) using ultraviolet C (UVC) has been proposed to disinfect different environments and surfaces contaminated by SARS-CoV-2. Herein, we performed a systematic scoping review strictly focused on peer-reviewed studies published in English that reported experimental results of UVC-based technologies against the SARS-CoV-2 virus. Studies were retrieved from PubMed and the Web of Science database. After our criterious screening, we identified 13 eligible articles that used UVC-based systems to inactivate SARS-CoV-2. We noticed the use of different UVC wavelengths, technologies, and light doses. The initial viral titer was also heterogeneous among studies. Most studies reported virus inactivation in well plates, even though virus persistence on N95 respirators and different surfaces were also evaluated. SARS-CoV-2 inactivation reached from 90% to 100% depending on experimental conditions. We concluded that there is sufficient evidence to support the use of UVC-based technologies against SARS-CoV-2. However, appropriate implementation is required to guarantee the efficacy and safety of UVC strategies to control the COVID-19 pandemic.

    Palavras-Chave: coronaviruses; inactivation; germicides; ultraviolet radiation; photoreactivation

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  • IPEN-DOC 29636

    SABINO, CAETANO P.; RIBEIRO, MARTHA S. ; WAINWRIGHT, MARK; ANJOS, CAROLINA dos; SELLERA, FABIO P.; DROPA, MILENA; NUNES, NATHALIA B.; BRANCINI, GUILHERME T.P.; BRAGA, GILBERTO U.L.; ARANA-CHAVEZ, VICTOR E.; FREITAS, RAUL O.; LINCOPAN, NILTON; BAPTISTA, MAURICIO S.. The biochemical mechanisms of antimicrobial photodynamic therapy. Photochemistry and Photobiology, v. 99, n. 2, p. 742-750, 2023. DOI: 10.1111/php.13685

    Abstract: The unbridled dissemination of multidrug-resistant pathogens is a major threat to global health and urgently demands novel therapeutic alternatives. Antimicrobial photodynamic therapy (aPDT) has been developed as a promising approach to treat localized infections regardless of drug resistance profile or taxonomy. Even though this technique has been known for more than a century, discussions and speculations regarding the biochemical mechanisms of microbial inactivation have never reached a consensus on what is the primary cause of cell death. Since photochemically generated oxidants promote ubiquitous reactions with various biomolecules, researchers simply assumed that all cellular structures are equally damaged. In this study, biochemical, molecular, biological and advanced microscopy techniques were employed to investigate whether protein, membrane or DNA damage correlates better with dose-dependent microbial inactivation kinetics. We showed that although mild membrane permeabilization and late DNA damage occur, no correlation with inactivation kinetics was found. On the other hand, protein degradation was analyzed by three different methods and showed a dose-dependent trend that matches microbial inactivation kinetics. Our results provide a deeper mechanistic understanding of aPDT that can guide the scientific community toward the development of optimized photosensitizing drugs and also rationally propose synergistic combinations with antimicrobial chemotherapy.

    Palavras-Chave: antimicrobial agents; photodynamic therapy; biochemical reaction kinetics; microbial drug resistance

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✔ É possível efetuar a busca de um autor ou um termo em todo o RD, por meio do Buscar no Repositório , isto é, o termo solicitado será localizado em qualquer campo do RD. No entanto esse tipo de pesquisa não é recomendada a não ser que se deseje um resultado amplo e generalizado.

✔ A pesquisa apresentará melhor resultado selecionando um dos filtros disponíveis em Navegar

✔ Os filtros disponíveis em Navegar tais como: Coleções, Ano de publicação, Títulos, Assuntos, Autores, Revista, Tipo de publicação são autoexplicativos. O filtro, Autores IPEN apresenta uma relação com os autores vinculados ao IPEN; o ID Autor IPEN diz respeito ao número único de identificação de cada autor constante no RD e sob o qual estão agrupados todos os seus trabalhos independente das variáveis do seu nome; Tipo de acesso diz respeito à acessibilidade do documento, isto é , sujeito as leis de direitos autorais, ID RT apresenta a relação dos relatórios técnicos, restritos para consulta das comunidades indicadas.

A opção Busca avançada utiliza os conectores da lógica boleana, é o melhor recurso para combinar chaves de busca e obter documentos relevantes à sua pesquisa, utilize os filtros apresentados na caixa de seleção para refinar o resultado de busca. Pode-se adicionar vários filtros a uma mesma busca.

Exemplo:

Buscar os artigos apresentados em um evento internacional de 2015, sobre loss of coolant, do autor Maprelian.

Autor: Maprelian

Título: loss of coolant

Tipo de publicação: Texto completo de evento

Ano de publicação: 2015

✔ Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

✔ 95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

✔ Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

✔ O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

✔ Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

✔ Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.