Cutaneous streptococcal abscess treated by photodynamic therapy

Background: Photodynamic therapy has been investigated in different areas of health through experimental conditions. Its action can alter fundamental structures for the survival of microorganisms without any development of microbial resistance.Materials and Methods: Young sheep presenting with abscess in the left forelimb caused by Streptococcus spp. was previously treated with antibiotics. There was no clinical improvement with the treatments, and the bacteria presented sensitivity in vitro. Therefore, Photodynamic therapy associating methylene blue and red laser (660 nm) was used to treat the abscess.Results: After a day of treatment, complete healing was witnessed with no recurrence was observed during the 3-month follow-up period.Conclusion: The scientific results of the antimicrobial effect of PDT proved to be a therapeutic option with great potential for clinical application.Keywords: Photoinactivation, Laser, Sheep, Streptococcus spp

Mycobacterium gordonae infection in a free-ranging green turtle (Chelonia mydas), Brazil

Mycobacteriosis is a well-known disease that has been reported in a variety of reptiles species. However, the occurrence of mycobacteriosis in sea turtles has been rarely documented, and most reports are from captive-reared animals. A juvenile green turtle (Chelonia mydas) was found stranded in March 2020, in Guanabara Bay, one of the most urbanized and polluted coastal areas in Rio de Janeiro, Southeastern Brazil. The turtle was in fair body condition and exhibited multiple cutaneous fibropapillomas, covering almost 60% of its body. Despite continued medical therapy, the animal died 60 days after initial supportive care. Necropsy revealed granulomatous pneumonia, hydropericardium, small granulomas in the myocardium, liver, spleen, thyroid and brain and caseous exudate in the meninges of the brain. The histopathological analysis showed disseminated granulomatous inflammation in various organs examined during necropsy. Intrahistiocytic acid-fast bacteria were observed in the liver, heart, lungs, kidneys, spleen, brain and adrenals. The blood culture collected shortly after the animal was admitted tested positive for Mycobacterium gordonae, after an 8-week incubation period; however, the animal had already died by the time the results were obtained. Postmortem examination confirmed systemic mycobacteriosis, identified as M. gordonae in blood, liver and lung cultures and by PCR amplification of DNA extracts from frozen tissue samples. This is the first report of a disseminated infection caused by M. gordonae in a free-ranging sea turtle. Although the source of this Mycobacterium remains unknown, it could potentially be related to anthropogenic activities (e.g., waste dumping or leakage from landfill sites). Increasing surveillance of Mycobacterium in wild sea turtles is of paramount importance to better understand the role of mycobacterial species as causative agents of infections in marine species

Letter to the Editor: Retrospective multicenter study reveals absence of MRSA-associated bovine mastitis in Brazil (1994 to 2016).

Made available in DSpace on 2020-01-14T18:14:15Z (GMT). No. of bitstreams: 1 Retrospectivemulticenterstudyrevealsabsence.pdf: 241426 bytes, checksum: deaa24c28e7420ff1b6f494ea79712df (MD5) Previous issue date: 2019bitstream/item/208728/1/Retrospective-multicenter-study-reveals-absence.pd

Serological survey of Neospora caninum and Toxoplasma gondii in shelter-housed cats infected with feline immunodeficiency virus, Brazil

Felines play a leading role in the epidemiology of Toxoplasma gondii infection, but there is scarce information about the epidemiology of Neospora caninum, particularly in feline immunodeficiency virus (FIV)-infected cats. Cats seropositive to T. gondii do not usually show symptoms unless they are immunosuppressed, such as FIV-infected cats. The same relationship remains poorly known for N. caninum, although it has been associated with neurological disorders in HIV-infected people. Since FIV-infected cats are prone to develop encephalitis of unknown etiology, this study aimed to evaluate the presence of specific antibodies to T. gondii and N. caninum in a shelter for stray cats naturally infected with FIV. A total of 104 serum samples from cats living in a shelter, located in São Paulo city (Brazil), was assessed for T. gondii and N. caninum specific antibody by indirect fluorescent-antibody test (IFAT). Of the 104 cats, 25 (24%) were infected with FIV and, aside from these, 8 (32%) had antibodies against T. gondii (titers from 16 to 128). Only 1 (4%) of the FIV infected cats had antibodies against N. caninum, which was the first record of coinfection. Among the FIV-naïve cats, 11 (14%) were positive for T. gondii (titers from 16 to 256) and only 1 (1.2%) had antibodies against N. caninum. Serologically positive reactions to T. gondii and N. caninum were not correlated with age or sex (p>0.05), and there was no correlation between FIV and the occurrence of anti-T. gondii or anti-N. caninum antibodies (p>0.05). Further studies encompassing larger cat populations from different origins and locations are essential to clarify the prevalence of T. gondii and N. caninum antibodies in FIV-positive cats.Os felinos têm um papel importante na epidemiologia da infecção por Toxoplasma gondii, mas pouco se sabe sobre a epidemiologia da infecção por Neospora caninum em gatos, particularmente em gatos infectados com o vírus da imunodeficiência felina (FIV). Gatos soropositivos para Toxoplasma gondii geralmente não apresentam sintomas a não ser que estejam imunossuprimidos, como gatos infectados com FIV. A mesma relação ainda é pouco conhecida para N. caninum, embora tenha sido associada a distúrbios neurológicos em pessoas infectadas pelo HIV. Considerando que gatos infectados com FIV são propensos a desenvolver encefalite de etiologia desconhecida, o presente estudo teve como objetivo avaliar a presença de anticorpos específicos para T. gondii e N. caninum em gatos infectados com FIV. Um total de 104 amostras de soro de gatos residentes em um abrigo na cidade de São Paulo, Brasil, foram avaliadas para a presença de anticorpos contra T. gondii e N. caninum pelo teste de imunofluorescência indireta (RIFI). Dos 104 gatos, 25 (24%) estavam infectados com FIV e destes 8, (32%) tinham anticorpos contra T. gondii (titulação entre 16 e 128). Apenas 1 (4%) dos gatos infectados com FIV apresentava anticorpos contra N. caninum, sendo este o primeiro registro dessa coinfecção. Entre os gatos não infectados com FIV, 11 (14%) foram positivos para T. gondii (titulação entre 16 e 256) e apenas 1 (1,2%) tinha anticorpos contra N. caninum. A reação sorologicamente positiva para T. gondii e N. caninum não foi correlacionada com a idade ou sexo (p> 0,05), nem houve correlação entre FIV e ocorrência de anticorpos para T. gondii ou N. caninum (p> 0,05). Estudos subsequentes abrangendo populações maiores de gatos de diferentes origens e locais são essenciais para esclarecer a prevalência de anticorpos contra T. gondii e N. caninum em animais acometidos por FIV.

Global priority multidrug-resistant pathogens do not resist photodynamic therapy.

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 drug-sensitive 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

Infertility diagnosis in jaguar (Panthera onca): case report

O presente trabalho relata um caso de infertilidade em uma onça-pintada (Panthera onca), macho, de 21 anos e 125 kg. São ressaltadas as alterações ocorridas nos espermatozoides, devido a estresse crônico, manejo alimentar inadequado e senescência reprodutiva.This work reports one case of infertility in a male jaguar (Panthera onca) aged 21 years and weighing 125 kg. Changes in sperm due to chronic stress, inadequate food handling and reproductive senescence are emphasized.

Inactivation Kinetics and Lethal Dose Analysis of Antimicrobial Blue Light and Photodynamic Therapy.

BACKGROUND: Photodynamic therapy (PDT) has been long used to treat localized tumors and 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). 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

CUTANEOUS STREPTOCOCCAL ABSCESS TREATED BY PHOTODYNAMIC THERAPY

Background: Photodynamic therapy has been investigated in different areas of health through experimental conditions. Its action can alter fundamental structures for the survival of microorganisms without any development of microbial resistance. Materials and Methods: Young sheep presenting with abscess in the left forelimb caused by Streptococcus spp. was previously treated with antibiotics. There was no clinical improvement with the treatments, and the bacteria presented sensitivity in vitro. Therefore, Photodynamic therapy associating methylene blue and red laser (660 nm) was used to treat the abscess. Results: After a day of treatment, complete healing was witnessed with no recurrence was observed during the 3-month follow-up period. Conclusion: The scientific results of the antimicrobial effect of PDT proved to be a therapeutic option with great potential for clinical application