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Highlights • Fungal infection asserts tissue damage in invasive fungal growth in skin lesions. • White-nose syndrome skin lesions are filled with Pseudogymnoascus destructans hyphae. • A single white-nose syndrome lesion contains about 50 pg of P. destructans DNA. • Our simulations suggest higher infection intensity in Nearctic bats. Abstract Where microbes colonizing skin surface may help maintain organism homeostasis, those that invade living skin layers cause disease. In bats, white-nose syndrome is a fungal skin infection that affects animals during hibernation and may lead to mortality in severe cases. Here, we inferred the amount of fungus that had invaded skin tissue of diseased animals. We used simulations to estimate the unobserved disease severity in a non-lethal wing punch biopsy and to relate the simulated pathology to the measured fungal load in paired biopsies. We found that a single white-nose syndrome skin lesion packed with spores and hyphae of the causative agent, Pseudogymnoascus destructans , contains 48.93 pg of the pathogen DNA, which amounts to about 1560 P destructans genomes in one skin lesion. Relating the information to the known UV fluorescence in Nearctic and Palearctic bats shows that Nearctic bats carry about 1.7 µg of fungal DNA per cm2, whereas Palearctic bats have 0.04 µg cm−2 of P. destructans DNA. With the information on the fungal load that had invaded the host skin, the researchers can now calculate disease severity as a function of invasive fungal growth using non-destructive UV light transillumination of each batʼs wing membranes. Our results will enable and promote thorough disease severity assessment in protected bat species without the need for extensive animal and laboratory labor sacrifices. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Silkworm, Bombyx mori, has various advantages as an experimental animal, such as the low cost for rearing and fewer ethical problems. Models utilizing silkworms of infection with pathogenic bacteria have been established for identification of genes encoding virulence factors by large‐scale in vivo screening. In this review, we describe recent progress in the study of silkworm infection models for elucidating the mechanisms of fungi infection. Silkworm infection models have been established for Candida albicans, Candida tropicalis, Candida glabrata and Cryptococcus neoformans, which are yeast type fungi, and Aspergillus fumigatus, Arthroderma vanbreuseghemii, Arthroderma benhamiae, Microsporum canis, Trichophyton rubrum, and Rhizopus oryzae, which are filamentous fungi. Novel genes encoding virulence factors in C. albicans and C. glabrata have been identified by using the silkworm infection models. We here outline the benefits of using silkworm infection models and a strategy for identifying the genes responsible for pathogenicity of microorganisms such as fungi. © 2019 The Authors. Microbiology and Immunology Published by The Societies and John Wiley & Sons Australia, Ltd. [ABSTRACT FROM AUTHOR]

Abstract Enterocytozoon bieneusi is a common pathogen in sheep and goats worldwide, threatening husbandry development and public health. However, there were few reports on native breeds of sheep and goats in China. In the present study, we investigated the prevalence and multi-locus genotypes (MLGs) of E. bieneusi in two important local breeds, black-boned sheep and goats, in Yunnan province, southwestern China. Of 661 faecal specimens collected from five counties of Yunnan province, 70 (10.59%) were positive for E. bieneusi infection. Infections were found in both black-boned sheep and goats, but no significant difference in prevalence was detected between two species. E. bieneusi was found in all age groups of black-boned sheep, while no infections were observed in 0–2-month black-boned goats. 12 genotypes were identified based on sequence variations of the internal transcribed spacer, including 10 known genotypes (BEB6, COS I, SX1, CM21, CHG3, CHG1, CHS5, EbpC, COS II, PigEb4) and two novel genotypes (named as YNS1 and YSM1), with BEB6 as the prevalent genotype both in black-boned sheep and goats. Phylogenetic analysis indicated that three genotypes of them, namely EbpC, CHS5 and PigEb4, were clustered into the zoonotic group 1, while the remaining nine genotypes were belonged to the host-adapted group 2. Multi-locus sequence typing (MLST) revealed 12 distinct multilocus genotypes (MLGs), with 11 MLGs detected in black-boned sheep and only one found in one black-boned goat. These findings expanded the reservoirs of E. bieneusi and provided fundamental data for controlling E. bieneusi infection in native small ruminants as well as other hosts in this province. Graphical abstract Unlabelled Image Highlights • E. bieneusi infection were found in both black-boned sheep and goats. • 12 genotypes were identified, including 10 known genotypes and two novel genotypes. • 12 distinct novel MLGs were identified. [ABSTRACT FROM AUTHOR]

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Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused by Ophidiomyces ophiodiicola, a fungus recently split from a complex of fungi long referred to as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). Here we review the current state of knowledge about O. ophiodiicola and SFD. In addition, we provide original findings which demonstrate that O. ophiodiicola is widely distributed in eastern North America, has a broad host range, is the predominant cause of fungal skin infections in wild snakes and often causes mild infections in snakes emerging from hibernation. This new information, together with what is already available in the scientific literature, advances our knowledge of the cause, pathogenesis and ecology of SFD. However, additional research is necessary to elucidate the factors driving the emergence of this disease and develop strategies to mitigate its impacts. [ABSTRACT FROM AUTHOR]

Disease can play an important role in structuring species communities because the effects of disease vary among hosts; some species are driven towards extinction, while others suffer relatively little impact. Why disease impacts vary among host species remains poorly understood for most multi-host pathogens, and factors allowing less-susceptible species to persist could be useful in conserving highly affected species. White-nose syndrome (WNS), an emerging fungal disease of bats, has decimated some species while sympatric and closely related species have experienced little effect. We analysed data on infection prevalence, fungal loads and environmental factors to determine how variation in infection among sympatric host species influenced the severity of WNS population impacts. Intense transmission resulted in almost uniformly high prevalence in all species. By contrast, fungal loads varied over 3 orders of magnitude among species, and explained 98% of the variation among species in disease impacts. Fungal loads increased with hibernating roosting temperatures, with bats roosting at warmer temperatures having higher fungal loads and suffering greater WNS impacts. We also found evidence of a threshold fungal load, above which the probability of mortality may increase sharply, and this threshold was similar for multiple species. This study demonstrates how differences in behavioural traits among species--in this case microclimate preferences--that may have been previously adaptive can be deleterious after the introduction of a new pathogen. Management to reduce pathogen loads rather than exposure may be an effective way of reducing disease impact and preventing species extinctions. [ABSTRACT FROM AUTHOR]

Different murine species differ in their susceptibility to systemic infection with Candida albicans, giving rise to varied host immune responses, and this is compounded by variations in virulence of the different yeast strains used. Hence, this study was aimed at elucidating the pathogenesis of a clinical C. albicans isolate (HVS6360) in a murine intravenous challenge model by examining the different parameters which included the counts of red blood cells and associated components as well as the organ-specific expression profiles of cytokines and chemokines. Kidneys and brains of infected mice have higher fungal recovery rates as compared to other organs and there were extensive yeast infiltration with moderate to severe inflammation seen in kidney and brain tissues. Red blood cells (RBCs) and haemoglobin (Hb) counts were reduced throughout the infection period. Pattern recognition receptors (PRRs), chemokines and cytokine transcription profiles were varied among the different organs (kidney, spleen and brain) over 72 h post infections. Transcription of most of the PRRs, cytokines and chemokines were suppressed at 72 h post infection in spleen while continuous expression of PRRs, cytokines and chemokines genes were seen in brain and kidney. Reduction in red blood cells and haemoglobin counts might be associated with the action of extracellular haemolysin enzyme and haeme oxygenase of C. albicans in conjunction with iron scavenging for the fungal growth. Renal cells responsible for erythropoietin production may be injured by the infection and hence the combined effect of haemolysis plus lack of erythropoietin-induced RBC replenishment leads to aggravated reduction in RBC numbers. The varied local host immune profiles among target organs during systemic C. albicans infection could be of importance for future work in designing targeted immunotherapy through immunomodulatory approaches. [ABSTRACT FROM AUTHOR]

Fungi represent emerging infectious threats to human populations worldwide. Mice and other laboratory animals have proved invaluable in modeling clinical syndromes associated with superficial and life-threatening invasive mycoses. This review outlines salient features of common vertebrate animal model systems to study fungal pathogenesis, host antifungal immune responses, and antifungal compounds. [ABSTRACT FROM AUTHOR]

Population declines due to amphibian chytridiomycosis among selected species of ranid frogs from western North America have been severe, but there is evidence that the Oregon spotted frog, Rana pretiosa Baird and Girard, 1853, displays resistance to the disease. Norepinephrine-stimulated skin secretions were collected from a non-declining population of R. pretiosa that had been exposed to the causative agent Batrachochytrium dendrobatidis. Peptidomic analysis led to identification and isolation, in pure form, of a total of 18 host-defense peptides that were characterized structurally. Brevinin-1PRa, -1PRb, -1PRc, and -1PRd, esculentin-2PRa and -PRb, ranatuerin-2PRa, -2PRb, -2PRc, and -2PRe, temporin-PRb and -PRc were identified in an earlier study of skin secretions of frogs from a different population of R. pretiosa known to be declining. Ranatuerin-2PRf, -2PRg, -2PRh, temporin-PRd, -PRe, and -PRf were not identified in skin secretions from frogs from the declining population, whereas temporin-PRa and ranatuerin-2PRd, present in skin secretions from the declining population, were not detected in the current study. All purified peptides inhibited the growth of B. dendrobatidis zoospores. Peptides of the brevinin-1 and esculentin-2 families displayed the highest potency (minimum inhibitory concentration = 6.25-12.5 μM). The study provides support for the hypothesis that the multiplicity and diversity of the antimicrobial peptide repertoire in R. pretiosa and the high growth-inhibitory potency of certain peptides against B. dendrobatidis are important in conferring a measure of resistance to fatal chytridiomycosis. [ABSTRACT FROM AUTHOR]

The author discusses the causes of white-nose syndrome (WNS) in bats referring to Geomyces destructans as the cause of mass mortality and large-scale population declines of certain bat species. The author highlights another finding wherein G. destructans have not caused mass mortality in wild European bats, in contrast to bats in North America with WNS. Moreover, the author is particular on fungal-influences and hyper-frequent arousal from hibernation as the cause of death in WNS bats.

The article describes two cases of feline orbital aspergillosis caused by Aspergillus udagawae and Aspergillus viridinutans. An overview of other reported feline cases of orbital aspergillosis is presented. It discusses the materials and methods used in both cases, the comparative sequence analysis and molecular analysis results obtained in the case study, and other findings obtained after diagnosing the subjects using histopathologic examination and mycological identification.

T helper (Th)1 and Th2 cells play decisive roles in the regulation of resistance vs. susceptibility to pulmonary cryptococcosis. To study the function of interleukin (IL)-4 receptor (IL-4R) on Th cells in pulmonary cryptococcosis, we infected mice specifically lacking IL-4Rα on CD4+ T cells (LckCreIL-4Rα−/lox mice) and IL-4Rα−/lox controls. LckCreIL-4Rα−/lox mice developed enhanced resistance accompanied by reduced pulmonary allergic inflammation and diminished production of the Th2 cytokines IL-4, IL-5, and IL-13 as compared with IL-4Rα−/lox mice. Polyfunctional antigen-specific Th2 cells producing simultaneously two or three Th2 cytokines were reduced in infected LckCreIL-4Rα−/lox mice, pointing to a critical role of polyfunctional Th2 cells for disease progression. Reduced Th2 polyfunctionality was associated with fewer pulmonary alternatively activated macrophages. This work is the first direct evidence for a critical contribution of the IL-4R on Th cells to Th2-dependent susceptibility during allergic bronchopulmonary mycosis. Moreover, the data demonstrate that the quality of the Th2 response has an impact on type 2 inflammation. The analysis of polyfunctional Th2 cells may be useful for monitoring the course of the disease. [ABSTRACT FROM AUTHOR]

Blastomycosis ( Blastomyces dermatitidis) is a fungal disease that is endemic in the southern United States. This case report illustrates the clinical, MRI and histopathologic findings in a dog with invasion of a retrobulbar blastomycotic lesion into the calvarium. A 5-year-old intact female Weimaraner was referred for a 2-month history of change in behavior and recent onset of visual deficits. Magnetic resonance imaging (MRI) examination revealed a large (5.8 × 2.0 × 2.5 cm) mass extending from the left orbit through a circular defect in the left cranioventral aspect of the calvarium caudally to the level of the pituitary fossa and interthalamic adhesion. The mass was heterogeneously iso- to hypointense on T2-W images, slightly hypointense on T1-W images, did not attenuate on fluid attenuated inversion recovery (FLAIR) images, and did not show evidence of susceptibility artifact on T2*-W gradient recalled echo (GRE) images. Vasogenic edema and associated mass effect were noted. The mass showed strong homogeneous contrast enhancement with well-defined margins and had thickening of the adjacent meninges (dural tail sign). Based on MRI findings a malignant neoplastic process was considered most likely and the patient was placed on oral prednisone to decrease peri-tumoral inflammation. The dog initially improved but was euthanized 3 weeks later for worsening clinical signs. Histopathologic assessment of the mass revealed marked pyogranulomatous optic neuritis with intralesional fungal yeasts consistent with blastomycosis ( Blastomyces dermatitidis). To our knowledge this is the first report of invasion of a retrobulbar blastomycotic lesion into the calvarium in a dog. [ABSTRACT FROM AUTHOR]

In an open non-randomized study, 90 cats with severe dermatophytosis were treated with 21 days of oral itraconazole at 10 mg/kg and one of three topical antifungal rinses applied twice weekly: lime sulphur (LSO); reformulated lime sulphur with an odour-masking agent (LSR); or a 0.2% miconazole nitrate and 0.2% chlorhexidine gluconate rinse (MC). Weekly examinations and fungal cultures were used to monitor the cats' response to therapy. If at day 42 of treatment cats were still strongly fungal culture positive and/or developing new lesions, they were retreated with oral itraconazole and LSO. Cats were not prevented from licking the solutions and none developed oral ulcerations. Thirty-one cats were treated with LSO, 27 with LSR and 32 with MC. The median number of days to cure was 30 (range 10-69 days) and 34 (range 23-80 days) for LSO and LSR, respectively. Thirty-two cats were treated with MC, and 13 of 32 cats required repeat treatment because of persistent culture-positive status and development of new lesions. Median number of days of treatment for the 19 cats that cured with MC was 48 (range 14-93 days). When the number of days to cure was compared between the groups, there was a significant difference between cats treated with LSO and LSR ( P = 0.029) and cats treated with LSO and MC ( P = 0.031), but no significant difference between the number of days to cure for cats treated with LSR and MC ( P = 0.91). [ABSTRACT FROM AUTHOR]

The article presents a study regarding the growth of the fungus Trichophyton mentagrophytes in mice. The results demonstrate that the fungus was grown from two mice showing clinical evidence of mouse favus. The infection in T. rodens demonstrated tinea lesions with a distinct inflammatory reaction and a tendency to invade hairs in an ectothrix fashion.

Cryptococcosis is a systemic, subacute to chronic mycosis, potentially fatal, affecting domestic and wild mammals, and humans (Queiroz et al., 2008).It is caused by the yeast belonging to the genus Cryptococcus, an opportunistic and ubiquitous pathogen that has tropism for the central nervous system (CNS), eye, lymph nodes and skin (Marcasso et al., 2005). In this study, we report a Cryptococcus sp. natural infection in the Chinchilla lanigera. The animal was attended at the Veterinary Hospital, Federal University of Paraná, Curitiba with a history of poor appetite and decreased bowel motility. The diagnosis was made by histopathologic evaluation of cecum sections which had pyogranulomatous, typhilitis with intralesional yeasts. Infection by this fungus has never been reported in chinchillas, as long as we know and the gastrointestinal infection is an uncommon site of lesion in animals and humans (Juan-Salk et al., 2003). [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the successful treatment of seven cases of Aspergillus species infection in reptiles with metabolically scaled oral doses of itraconazole. Diagnosis for the fungal disease was performed by veterinary histopathology after biopsy of affected tissue and staining with periodic acid-Schiff stain. Findings indicate that the use of itraconazole appears to be safe during the typical 20-week duration treatment for Aspergillus species infections.