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Open Veterinary Journal 2022External otitis is common in dogs, and one of the main agents involved is , a yeast belonging to the otic microbiota. Empirical treatment can fail; therefore, it is...
BACKGROUND
External otitis is common in dogs, and one of the main agents involved is , a yeast belonging to the otic microbiota. Empirical treatment can fail; therefore, it is essential to know the antifungal susceptibility profile to prescribe appropriate treatment, a fact scarcely reported in Chile.
AIM
This study aimed to determine the antifungal sensitivity of isolated from the external auditory canal of dogs in central Chile.
METHODS
Ear swabs from 30 dogs (15 healthy and 15 with external otitis) were used. Samples were subjected to cytology and fungal culture. The antifungal susceptibility was determined according to clinical and laboratory standards institute (CLSI) document M44A-2 using the disk diffusion test from amphotericin B, Caspofungin, fluconazole, nystatin, clotrimazole, and voriconazole were used.
RESULTS
The prevalence of was 66.7% from 8 healthy dogs and 12 with otitis. While fungal culture was not associated with the patient's clinical condition ( = 0.24), the yeast count by cytology was significantly higher in dogs with otitis ( = 0.003). The strains were sensitive to all antifungals except for Caspofungin, where 55% of the strains were resistant.
CONCLUSION
is isolated more frequently in dogs with otitis, and the ear cytological examination is useful to differentiate colonized dogs versus dogs with otitis. In addition, most antifungals are active against this yeast, except Caspofungin, an antifungal used in human medicine. This situation should be further monitored in epidemiological programs to evaluate the possible impact on Chilean public health.
Topics: Animals; Antifungal Agents; Caspofungin; Chile; Dermatomycoses; Dog Diseases; Dogs; Malassezia; Otitis Externa; Saccharomyces cerevisiae
PubMed: 35342729
DOI: 10.5455/OVJ.2022.v12.i1.12 -
Case Reports in Infectious Diseases 2022Invasive disease due to infection is uncommon but increasingly recognized in children, especially neonates on parenteral nutrition or immunocompromised children. We...
Invasive disease due to infection is uncommon but increasingly recognized in children, especially neonates on parenteral nutrition or immunocompromised children. We describe a case of fungemia in a demographically distinct patient and discuss the workup and current strategies for managing this infection in the setting of a central venous catheter.
PubMed: 35096432
DOI: 10.1155/2022/8636582 -
Veterinary Medicine and Science Mar 2022The antifungal efficacy of cold atmospheric microwave plasma (CAMP) against Malassezia pachydermatis has not been to be evaluated.
BACKGROUND
The antifungal efficacy of cold atmospheric microwave plasma (CAMP) against Malassezia pachydermatis has not been to be evaluated.
OBJECTIVE
To examine the antifungal effects of CAMP against M. pachydermatis and its synergistic effects with chlorhexidine gluconate (CHX).
METHODS
A M. pachydermatis isolate was collected from a dog with otitis externa and Malassezia dermatitis at the Seoul National University Veterinary Medical Teaching Hospital. The antifungal effect was determined by applying CAMP to a M. pachydermatis isolate that was incubated for 3 days at 37°C. After 1, 2, 3 and 5 min of application, the efficacy of the plasma treatment was determined according to the number of colony forming units (CFUs). A mixture consisting of inoculum and CHX was applied to evaluate the synergistic effect of the plasma treatment in the same way.
RESULTS
The application of CAMP showed significant antifungal effects against M. pachydermatis. The antifungal effect of CAMP was enhanced by an increased exposure time and output power. The application of CAMP with 0.02% and 0.2% CHX resulted in lower survival rates against M. pachydermatis when compared with its sole application at 1 or 2 min.
CONCLUSIONS
The study findings demonstrate that CAMP has a potential as a new antifungal option for M. pachydermatis and has synergistic antifungal effects with CHX in vitro. Clinical applications for CAMP are necessary to assess the antifungal efficacy for patients.
Topics: Animals; Antifungal Agents; Chlorhexidine; Dog Diseases; Dogs; Humans; Malassezia; Microwaves; Plasma Gases
PubMed: 35089639
DOI: 10.1002/vms3.719 -
Journal of Enzyme Inhibition and... Dec 2022Warm-blooded animals may have on healthy skin, but changes in the skin microenvironment or host defences induce this opportunistic commensal to become pathogenic....
Warm-blooded animals may have on healthy skin, but changes in the skin microenvironment or host defences induce this opportunistic commensal to become pathogenic. Malassezia infections in humans and animals are commonly treated with azole antifungals. Fungistatic treatments, together with their long-term use, contribute to the selection and the establishment of drug-resistant fungi. To counteract this rising problem, researchers must find new antifungal drugs and enhance drug resistance management strategies. Cyclic adenosine monophosphate, adenylyl cyclase, and bicarbonate have been found to promote fungal virulence, adhesion, hydrolase synthesis, and host cell death. The CO/HCO/pH-sensing in fungi is triggered by HCO produced by metalloenzymes carbonic anhydrases (CAs, EC 4.2.1.1). It has been demonstrated that the growth of can be inhibited by primary sulphonamides, which are the typical CA inhibitors. Here, we report the cloning, purification, and characterisation of the -CA (MpaCA) from the pathogenic fungus , which is homologous to the enzyme encoded in the genome of and , that are responsible for dandruff and seborrhoeic dermatitis. Fungal CAs could be thus considered a new pharmacological target for combating fungal infections and drug resistance developed by most fungi to the already used drugs.
Topics: Carbonic Anhydrase Inhibitors; Carbonic Anhydrases; Dose-Response Relationship, Drug; Malassezia; Molecular Structure; Recombinant Proteins; Structure-Activity Relationship
PubMed: 34894958
DOI: 10.1080/14756366.2021.1994559 -
International Journal of Molecular... Nov 2021Fungi are exposed to various environmental variables during their life cycle, including changes in CO concentration. CO has the potential to act as an activator of...
Fungi are exposed to various environmental variables during their life cycle, including changes in CO concentration. CO has the potential to act as an activator of several cell signaling pathways. In fungi, the sensing of CO triggers cell differentiation and the biosynthesis of proteins involved in the metabolism and pathogenicity of these microorganisms. The molecular machineries involved in CO sensing constitute a promising target for the development of antifungals. Carbonic anhydrases (CAs, EC 4.2.1.1) are crucial enzymes in the CO sensing systems of fungi, because they catalyze the reversible hydration of CO to proton and HCO. Bicarbonate in turn boots a cascade of reactions triggering fungal pathogenicity and metabolism. Accordingly, CAs affect microorganism proliferation and may represent a potential therapeutic target against fungal infection. Here, the inhibition of the unique -CA (MpaCA) encoded in the genome of , a fungus with substantial relevance in veterinary and medical sciences, was investigated using a series of conventional CA inhibitors (CAIs), namely aromatic and heterocyclic sulfonamides. This study aimed to describe novel candidates that can kill this harmful fungus by inhibiting their CA, and thus lead to effective anti-dandruff and anti-seborrheic dermatitis agents. In this context, current antifungal compounds, such as the azoles and their derivatives, have been demonstrated to induce the selection of resistant fungal strains and lose therapeutic efficacy, which might be restored by the concomitant use of alternative compounds, such as the fungal CA inhibitors.
Topics: Animals; Animals, Domestic; Antifungal Agents; Carbonic Anhydrase I; Carbonic Anhydrase Inhibitors; Humans; Malassezia; Molecular Structure; Mycoses; Structure-Activity Relationship; Sulfonamides
PubMed: 34830480
DOI: 10.3390/ijms222212601 -
BMC Veterinary Research Aug 2021Lifestyle factors such as hair length, the frequency of ear cleaning and bathing, age, cat rearing, and sex may contribute to opportunistic yeast infections in the...
BACKGROUND
Lifestyle factors such as hair length, the frequency of ear cleaning and bathing, age, cat rearing, and sex may contribute to opportunistic yeast infections in the external ear canal of cats. This study aimed to determine the prevalence of commensal yeast organisms in cats' external ear canals, evaluate their predisposing lifestyle factors, and test the susceptibility of Malassezia pachydermatis to antifungal agents.
RESULTS
A total of 53 cats (33 male and 20 female) seronegative for feline leukemia virus and feline immunodeficiency virus were enrolled in this study. Their mean age (± standard deviation) was 6.04 (± 3.49) years. Fungal cultures and polymerase chain reaction tests were performed to identify the yeast species derived from the external ear canal. The association between lifestyle factors and the presence of M. pachydermatis was evaluated using Fisher's exact test. The susceptibility of M. pachydermatis to antifungal agents was also analyzed. M. pachydermatis was the most frequently recovered yeast species, with a prevalence of 50.94 % (95 % confidence interval [CI]: 36.84-64.94 %). There was an association between hair length and a positive culture for M. pachydermatis (p = 0.0001). The odds of a negative culture for M. pachydermatis among short-haired cats was 11.67 (95 % CI, 3.22-42.24) times higher than that among long-haired cats (p = 0.0002). There was also an association between the frequency of ear cleaning and the presence of M. pachydermatis (p = 0.007). The odds of a negative culture for M. pachydermatis in cats that were receiving ear cleaning at intervals of ≤ 2 weeks was 5.78 (95 % CI, 1.67-19.94) times greater than that of cats receiving ear cleaning at intervals greater than 2 weeks or never (p = 0.0055). Ranges of minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations for itraconazole, ketoconazole, miconazole, and terbinafine against M. pachydermatis were ≤ 0.063-4 and ≤ 0.063-≥32, ≤ 0.063-8 and 0.125-≥32, ≤ 0.063-≥32 and 0.5-≥32, and ≤ 0.016-1 and 0.125-8 µg/ml, respectively.
CONCLUSIONS
M. pachydermatis was the most commonly identified yeast organism in the external ear canal of healthy cats. Hair length and the frequency of ear cleaning played a role in the colonization of M. pachydermatis. The M. pachydermatis isolates had various MIC levels for common fungicides.
Topics: Animal Fur; Animals; Antifungal Agents; Cat Diseases; Cats; Ear Canal; Female; Malassezia; Male; Prevalence; Yeasts
PubMed: 34454490
DOI: 10.1186/s12917-021-02995-7 -
Journal of Veterinary Pharmacology and... Nov 2021Canine otitis externa is frequently encountered in veterinary practice, caused by primary factors with bacteria and yeast overgrowth acting as secondary and perpetuating...
Canine otitis externa is frequently encountered in veterinary practice, caused by primary factors with bacteria and yeast overgrowth acting as secondary and perpetuating factors. The pharmacological support includes anti-inflammatory, antimicrobials, and antimycotic drugs, but therapeutic failure and antimicrobial resistance are leading to alternative strategies based on phytotherapic products. This study aimed to evaluate an essential oil blend (Otogen ) to treat otitis externa in dogs. The experimental design was divided in: (a) an in vitro approach, based on the European Normative UNI EN 1275:2006, to assess the efficacy of the product against the most frequently isolated microorganisms during otitis externa. (b) an in vivo part, 12 owned dogs presenting with acute otitis externa were enrolled. A significant growth reduction (>99.9%) of Malassezia pachydermatis and Candida albicans after 15 min of contact and Pseudomonas aeruginosa after 1 h of incubation was recorded. For Staphylococcus pseudintermedius, 50% of growth reduction were appreciated after 15 min. Results obtained in vivo after 7 days of blend administration, noted a significant improvement of all the considered parameters (most important were head shaking, erythema, and scraping). The results obtained may support the usefulness of the tested phytotherapic blend to manage acute otitis externa in dogs.
Topics: Animals; Antifungal Agents; Dog Diseases; Dogs; Malassezia; Microbial Sensitivity Tests; Otitis Externa; Staphylococcus
PubMed: 34258792
DOI: 10.1111/jvp.13000 -
Microbiology Resource Announcements May 2021We have assembled the genome sequence of Malassezia pachydermatis isolated from a canine otitis sample with Nanopore-only long reads. With 99× coverage and 8.23 Mbp,...
We have assembled the genome sequence of Malassezia pachydermatis isolated from a canine otitis sample with Nanopore-only long reads. With 99× coverage and 8.23 Mbp, the genome sequence was assembled in 10 contigs, with 6 of them corresponding to chromosomes, improving the scaffolding of previous genome assemblies for the species.
PubMed: 34042482
DOI: 10.1128/MRA.00205-21 -
Wiadomosci Lekarskie (Warsaw, Poland :... 2021The aim of the study is to reveal in the experiment the morphological features of the infected skin wounds healing, which are a manifestation of acne vulgaris severe and...
OBJECTIVE
The aim of the study is to reveal in the experiment the morphological features of the infected skin wounds healing, which are a manifestation of acne vulgaris severe and very severe forms, using a gel with carbon dioxide extract of hops.
PATIENTS AND METHODS
Materials and methods: An experimental study was carried out on 80 male WAG rats of three months of age. The animals were divided into 9 groups. Group 1 consisted of intact animals (n=6). Group 2 was represented by animals (n=6), which had hair epilation on the dorsal surface of the body in an area of 1 сm2, followed by application of 2 ml of placebo gel to this area. Group 3 included animals (n=6), which were epilated on the dorsal surface of the body in an area of 1 сm2 and applied 2 ml of 1 % gel with carbon dioxide extract of hops. Group 4 included rats (n=6), which were epilated on the dorsal surface of the body in an area of 1 сm2 and simulated thermal damage. Group 5 was represented by 10 rats, who were epilated on the dorsal surface of the body in an area of 1 сm2, simulated thermal damage, followed by applying 2 ml of placebo gel to the wound surface. Group 6 included rats (n=10), who underwent measures similar to group 5, followed by application of 2 ml of 1 % gel with carbon dioxide extract of hops to the wound surface. In group 7, there were 6 rats, which were epilated on the dorsal surface of the body in an area of 1 сm2, thermal damage to the skin with underlying soft tissues was simulated, followed by application to the wound surface the reference strains of Staphylococcus aureus, Streptococcus pyogenes, Proteus vulgaris, Propionibacterium acnes, Escherichia coli, Pseudomonas aeruginosa, Malassezia slooffiae, Malassezia pachydermatis, Candida albicans, Candida parapsilosis. In groups 8 and 9, there were 15 rats each, which underwent measures similar to group 7, followed by applying 2 ml of placebo gel on its surface on the next day after infection of the wound in group 8, and in group 9 - 2 ml of 1 % gel with carbon dioxide extract hops. The material for the study was the skin with underlying soft tissues. It was used histological, histochemical, morphometric and statistical methods.
RESULTS
Results: This experimentally created gel with carbon dioxide extract of hops activates separation processes of horny masses from the surface of the epidermis, cleaning the pores of the skin; stimulating the proliferative activity of the epidermis, which is located in the marginal sections of the wound or covers the surface of the regenerate; activating the processes of cleansing the wound from necrotic tissue; activating the growth and maturation of granulation tissue with its subsequent transformation into connective tissue. It has anti-inflammatory, bactericidal and antimycotic effects, normalizing skin microbiocenosis.
CONCLUSION
Conclusions: The complex morphological study has showed that gel with carbon dioxide extract of hops is a highly effective drug in treatment of severe and very severe acne vulgaris, characterized by the development of deep and infected wound defects.
Topics: Acne Vulgaris; Animals; Carbon Dioxide; Humulus; Malassezia; Male; Rats; Wound Healing; Wound Infection
PubMed: 33851599
DOI: No ID Found -
Biology Methods & Protocols Jan 2021The availability of long-read technologies, like Oxford Nanopore Technologies, provides the opportunity to sequence longer fragments of the fungal ribosomal operon, up...
The availability of long-read technologies, like Oxford Nanopore Technologies, provides the opportunity to sequence longer fragments of the fungal ribosomal operon, up to 6 Kb (18S-ITS1-5.8S-ITS2-28S) and to improve the taxonomy assignment of the communities up to species level and in real-time. We assess the applicability for taxonomic assignment of amplicons targeting a 3.5 Kb region (V3 18S-ITS1-5.8S-ITS2-28S D2) and a 6 Kb region (V1 18S-ITS1-5.8S-ITS2-28S D12) with the What's in my pot (WIMP) classifier. We used the ZymoBIOMICS mock community and different microbiological fungal cultures as positive controls. Long amplicon sequencing correctly identified and from the mock community and , and from the microbiological cultures. Besides, we identified in a culture mislabelled as spp. We applied the same approach to external otitis in dogs. was the dominant fungal genus in dogs' ear skin, whereas was the main species in the healthy sample. Conversely, we identified a higher representation of and in otitis affected samples. We demonstrate the suitability of long ribosomal amplicons to characterize the fungal community of complex samples, either healthy or with clinical signs of infection.
PubMed: 33506108
DOI: 10.1093/biomethods/bpaa026