Comprehensive genome and transcriptome analysis of the dermatophyte Trichophyton schoenleinii reveals the candidate pathogenic genes.

BACKGROUND: Trichophyton schoenleinii is an anthropophilic dermatophyte that causes tinea favosa. Nowadays, it remains an important pathogen in some regions of the world, mainly epidemic in Africa and West Asia. Despite the medical importance of T. schoenleinii infections, a high-quality reference genome for T. schoenleinii is still unavailable, neither its transcriptomic profile. OBJECTIVES: The aim of the current study was to improve understanding of the underlying pathogenic mechanism of T. schoenleinii, and to define the candidate pathogenic genes of T. schoenleinii. METHODS: Comprehensive genomic analysis of T. schoenleinii was carried out by Illumina and PacBio sequencing platforms. Transcriptome profiles of T. schoenleinii cultured in vitro in two media containing either keratin or soy protein were determined using RNA sequencing (RNA-seq) technology. RESULTS: Here, we present the first draft genome sequence of T. schoenleinii strain T2s, which consists of 11 scaffolds containing 7474 predicted genes. Transcriptome analysis showed that genes involved in keratin hydrolysis have higher expression in T. schoenleinii grown in keratin medium, including genes encoding proteases, cysteine dioxygenase and acetamidase. Other genes with higher expression include genes encoding the components of the pH-responsive signal transduction pathways and transcription factors, many of which may play a role in pathogenicity. CONCLUSION: In summary, this study provides new insights into the pathogenic mechanism of T. schoenleinii and highlights candidate genes for further development of novel targets in disease diagnosis and treatment of tinea favosa.

Aetiology of superficial fungal infections of the foot in urban outpatients in mainland China: A multicentre, prospective case study.

BACKGROUND: In China, the prevalence of superficial fungal infections of the foot is high and recurrence is common. However, a prospective, large-scale and multicentre study on the aetiology of superficial fungal infections of the foot is still lacking. OBJECTIVES: To study the epidemiology of aetiological agents of superficial fungal infections of the foot in urban outpatients in mainland China, as well as to understand the aetiology features of the pathogenic agent. METHODS: The study was designed as a multicentre, prospective epidemiological survey. A total of 1704 subjects were enrolled from seven geographical areas in mainland China. For each subject, one mycological sample and one bacterial sample were collected. KOH wet mount examination and culture were performed at local laboratories. The bacterial results were only reported in those with positive mycology. Further morphological identification and, if necessary, molecular biological identification were conducted in a central laboratory. RESULTS: Of 1704 enrolled subjects, 1327 (77.9%) subjects had positive fungal culture results. The incidence of dermatophytes, yeasts and moulds was 90.1%, 8.1% and 1.1%, respectively. The most frequently isolated aetiological agent (fungus) was Trichophyton rubrum. Moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections. The most frequently isolated bacterial genus in patients was Staphylococcus. CONCLUSION: This study prospectively investigated the clinical and mycological features of human dermatophytosis in mainland China. T rubrum was the most frequently isolated fungus, and moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections.

The efflux pump inhibitor tetrandrine exhibits synergism with fluconazole or voriconazole against Candida parapsilosis.

In the last two decades, with the wide use of azoles, antifungal resistance among Candida parapsilosis has considered a matter of concern worldwide. The aim of this study is to evaluate the antifungal potentials of tetrandrine (TET) alone and in combination with fluconazole (FLC)/voriconazole (VRC) against C. parapsilosis. Susceptibility tests were performed by microdilution method, checkerboard assay, time-kill test, spot assay. Subsequently, rhodamine 6G efflux test and the expressions of transporter related genes, namely CDR1 and MDR1 for C. parapsilosis were analyzed by qRT-PCR. The susceptibility test showed that TET presented strong synergism with FLC and VRC with fractional inhibitory concentration index (FICI) in a range of 0.094-0.562. The susceptibility results were also confirmed by spot assay and time-kill studies. With TET treatment, a vast quantity of rhodamine 6G could not be pumped out from the cells as considerably intracellular red fluorescence was accumulated. Meanwhile, the expressions of efflux-associated genes presented varying degrees of inhibition. These results indicated that TET was a decent antifungal synergist to promote the antifungal efficacy of FLC/VRC, and the underlying antifungal mechanism might be associated with the inhibition of efflux pump and the elevation of intracellular drug content.

Successful Treatment of Eczema-Like Mucormycosis in a Child by Combination of Intravenous Drip and Percutaneous Injection Amphotericin B.

We report a case of eczema-like cutaneous mucormycosis caused by Rhizopus arrhizus. A 4-year-old child was presented to our hospital with a history of gradually enlarging papule and plaque in the periumbilical area for nearly 4 years since 2 weeks after his birth, and it has been misdiagnosed as eczema for nearly 3 years. Based on histopathology examination, the fungus culture test and DNA sequencing, it was revealed that R. arrhizus should be the responsible fungus for skin infection. The patient was successfully cured by combination of intravenous drip and percutaneous injection amphotericin B for nearly 3 months, and no recrudescence was seen during a follow-up of 6-month observation.

Successful Treatment by Surgery of a Primary Cutaneous Mucormycosis Caused by Mucor irregularis.

We report a case of primary cutaneous mucormycosis caused by Mucor irregularis. A 66-year-old man was presented to our hospital with a history of gradually enlarging plaque on the right leg for about a year. The identification of pathogen based on the fungus morphology and DNA sequencing revealed M. irregularis as the responsible fungus for skin lesion. The lesion was removed incidentally by a surgery procedure, and no recrudescence was seen during a follow-up of 24-month observation.

The first case of phaeohyphomycosis caused by Rhinocladiella basitona in an immunocompetent child in China.

We present the first case of phaeohyphomycosis caused by Rhinocladiella basitona (R. basitona) in China and describe the mycological characteristics of this pathogen. A 11-year-old girl was presented with plaque on her face for 3 years. Diagnosis was based on histopathology, mycology, and molecular identification. The patient was treated with terbinafine and itraconazole. This case is the second of phaeohyphomycosis caused by R. basitona in the world (previously belonging to Geniculosporium).

Evaluation of the skin sensitization potential of chemicals in THP-1/keratinocyte co-cultures.

Many attempts have been made to develop in vitro sensitization tests that employ dendritic cells (DCs), DC-like cell lines or keratinocytes. The aim of the present investigation was to establish a co-culture of THP-1 cells and keratinocytes for evaluation of skin sensitization potential of chemicals. Co-cultures were constructed by THP-1 cells cultured in lower compartments and keratinocytes cultured in upper compartments of cell culture inserts. After 24 h exposure to sensitizers (2, 4-dinitrochlorobenzene, p-phenylenediamine, formaldehyde, nickel sulfate, isoeugenol and eugenol) and non-sensitizers (sodium lauryl sulfate, benzalkonium chloride and lactic acid), the expression of CD86 and CD54 on THP-1 cells were evaluated by flow cytometry, and cell viabilities were determined. The sensitizers induced the augmentation of CD86 and CD54 expression, but the non-sensitizers had no significant effect. Compared with mono-cultures of THP-1 cells, the augmentation of CD86 and CD54 could be detected even at a non-toxic concentration of sensitizers in THP-1 cell/keratinocyte co-cultures. Moreover, isoeugenol was distinguished as a sensitizer in co-cultures, but failed to be identified in mono-cultures. These results revealed that the co-cultures of THP-1 cells and keratinocytes were successfully established and suitable for identifying sensitizers using CD86 and CD54 expression as identification markers.

A simple and reliable PCR-restriction fragment length polymorphism assay to identify Candida albicans and its closely related Candida dubliniensis.

Candida dubliniensis is an emerging pathogen capable of causing superficial as well as systemic infections. Due to its close similarity to C. albcians, conventional methods based on phenotypic traits are not always reliable in identification of C. dubliniensis. In this study, we developed a PCR-restriction fragment length polymorphism (RFLP) assay to identify and discriminate between the two closely related species. The D1/D2 region of 28S rDNA was amplified by PCR and enzymatically digested by ApaI and BsiEI respectively. PCR products of both species were digested into two fragments by ApaI, but those of other yeast species were undigested. BsiEI cut the PCR products of C. albicans into two fragments but not those of C. dubliniensis. Thus two species were differentiated. We evaluated 10 reference strains representing 10 yeast species, among which C. albicans and C. dubliniensis were successfully identified. A total of 56 phenotypically characterized clinical isolates (42 C. albicans isolates and 14 C. dubliniensis isolates) were also investigated for intra-species variability. All tested isolates produced identical RFLP patterns to their respective reference strains except one initially misidentified isolate. Our method offers a simple, rapid and reliable molecular method for the identification of C. albicans and C. dubliniensis.

Phaeohyphomycosis in China.

Background: Due to more attentions paid to melanized fungi over the past few decades and under the background of the global coronavirus disease 2019 pandemic (COVID-19) the fact that the virus itself and the immunosuppressive agents such as glucocorticoids can further increase the risk of infections of deep mycoses, the number of patients with phaeohyphomycosis (PHM) has a substantial increase. Their spectrum is broad and the early diagnosis and treatments are extremely sticky. This study aims to more comprehensively understand the clinical features of phaeohyphomycosis in China over 35 years and to establish a more applicable systematical classification and severity grades of lesions to guide treatments and prognosis. Methods: We reviewed 174 cases of proven phaeohyphomycosis reported in Chinese and English language literature from 1987 to 2021 and we also made the accurate classification definitions and detailed information about the epidemiology, species of clinical dematiaceous fungi, minimum inhibitory concentration values, clinical features, treatments, and prognosis. Results: The mortality of cerebral, disseminated and pulmonary phaeohyphomycosis are 55%, 36%, and 25%. Nearly 19% of patients had poor quality of life caused by the complications such as disability, disfigurements, and blindness. The overall misdiagnosis rate of phaeohyphomycosis was 74%. Moderate to severe rashes are accounting for 82% of subcutaneous phaeohyphomycosis. The areas of the head and face are mostly affected accounting for 16% of severe rashes. Nearly 30% of invasive infections of phaeohyphomycosis are triggered by recurrent lesions. Voriconazole, itraconazole, amphotericin B deoxycholate (AmB-DOC), and terbinafine were most commonly used but diagnosis and treatments of phaeohyphomycosis remain challenging in reality. Conclusions: Our classifications are likely to be more practical and easier to popularize, and there are still also plenty of characteristics in these non-specific lesions. There're no significant variations in cure rates, or death rates between three grades of lesions. But patients with severe rashes have longer courses and lower effective rates.

Biofilm Alterations on the Stepwise Acquisition of Fluconazole-resistant Candida Albicans Isolates.

By assessing and comparing the phenotypic changes on the stepwise acquisition of fluconazole resistant Candida albicans isolates, we could find and describe the relationship between drug resistance and biofilm formation ability in a series of clonal strains. Methods: We performed antifungal susceptibility of five drugs (fluconazole, itraconazole, voriconazole, caspofungin and amphotericin B) to further verify the antifungal activity of the six isolates in vitro. Then we combined hyphal formation assay, cell surface hydrophobicity test positively related to adherence ability, and biofilm assays in vitro to observe and compare the phenotypic characteristics of our six clonal strains. Results: Biofilm capability is enhanced for four drug- intermediate strains, whereas the initial susceptible strain and the final resistant strain are both poor in adherence, hyphal growth and biofilm formation. Conclusions: It was suggested that the biofilm formation ability were not absolutely related to the degree of fluconazole resistance.

Direct detection and differentiation of causative fungi of onychomycosis by multiplex polymerase chain reaction-based assay.

A rapid and reliable triplex PCR procedure was developed to detect pathogenic fungi directly from specimens of onychomycosis. One hundred and four patients were included in this study. Of them, forty-five (43.3%) were finally diagnosed with onychomycosis according to the diagnostic criteria. The sensitivity of PCR, microscopy and culture were 93.3%, 100% and 64.4%, respectively; the specificities were 100%, 86.4% and 100%, respectively; the positive predictive values were 100%, 84.9% and 100%, respectively; the negative predictive values were 95.2%, 100% and 78.7%, respectively. This molecular diagnostic process could distinguish the 3 groups of pathogens in onychomycosis (dermatophyte, yeast and mold) and could be completed within 8 h. This multiplex PCR assay could used in laboratories with no mycological specialization for rapid etiologic diagnosis and treatment selection, especially in suspected fungus cases if they can not be detected by conventional methods or if a rapid diagnosis of onychomycosis is needed.

In vitro evaluation of phospholipase, proteinase, and esterase activities of Candida parapsilosis and Candida metapsilosis.

The aim of this study is to characterize extracellular phospholipase, proteinase, and esterase activities of Candida parapsilosis and C. metapsilosis isolated from clinical sources. Using PCR-restriction fragment length polymorphism (PCR-RFLP) of the secondary alcohol dehydrogenase (SADH) gene fragment, we identified 20 as C. parapsilosis and 11 as C. metapsilosis from 31 isolates of C. parapsilosis species complex. No C. orthopsilosis was identified. A significantly high isolation frequency of C. metapsilosis (35.5%) was observed. Subsequent evaluation of enzymatic profile showed that 90.5% of C. parapsilosis and 91.7% of C. metapsilosis isolates were phospholipase producers. No difference in phospholipase activity was observed between two species. In terms of proteinase, 81.0% of C. parapsilosis and 83.3% of C. metapsilosis isolates were positive. A higher level of proteinase activity was detected in C. parapsilosis. A remarkably high proportion of both C. parapsilosis and C. metapsilosis isolates exhibited strong phospholipase and proteinase activities, suggesting that the production of these two enzymes might be common for them. On the other hand, both species similarly displayed rare esterase activity, with only one C. parapsilosis and two C. metapsilosis isolates being positive. Our data may further add to the confusion concerning the hydrolytic enzymatic activities of the C. parapsilosis complex, and a wider collection of isolates and standardized methods may help to address the issue.

[Effect of phospholipomannan of Candida albicans on the production of interleukin 6 and interleukin 8 in monocytes].

OBJECTIVE: To investigate whether Candida albicans-native phospholipomannan (PLM) induce an inflammation response through Toll-like receptor(TLRé2 in human acute monocytic leukemia cell line (THP-1) cells. METHODS: Human THP-1 monocytes were challenged with PLM in vitro. The mRNA expressions of TLR2, TLR4, proinflammatory cytokine [interleukin(IL)-6], and chemokine (IL-8) were assayed by real time reverse transcription polymerase chain reaction. The secretions of IL-6 and IL-8 were measured by enzyme-linked immunosorbent assay. The expression of TLR2 was analyzed with Western blot. RESULTS: PLM increased the mRNA expressions and secretions of proinflammatory cytokines (IL-6) and chemokines (IL-8) in THP-1 cells (all P=0.0000). PLM up-regulated the mRNA and protein levels of TLR2 (P=0.0000), whereas the mRNA level of TLR4 was not altered. PLM hydrolyzed with ß-D-mannoside manno hydrolase failed to induce gene and protein expressions of TLR2, IL-6, and IL-8. Anti-TLRS-neutralizing antibody blocked the PLM-induced secretions of IL-6 and IL-8 in THP-1 cells (P = 0.0003, P = 0.0010). CONCLUSION: Canidada albicans-native PLM may contribute to the inflammatory responses during Candida infection in a TLR2-dependent manner.

Onychomycosis caused by Pichia guilliermondii: A case report and mini-review.

Onychomycosis has been reported to be mainly caused by dermatophytes. Recently, more attention has been paid to yeast for its increasing morbidity, especially the candida specices. Here we reported a fingernail infection caused by Pichia guilliermondii, the sexual reproduction period of Candida guilliermondii. Itraconazole was used for three courses, and the patient achieved improvement without any significant side-effects. This might be the first onychomycosis case of Candida guilliermondii.

[Dominant species of cephalopods and their niche characteristics in offshore of northern South China Sea]. / å—æµ·åŒ—éƒ¨è¿‘æµ·å¤´è¶³ç±»ä¼˜åŠ¿ç§åŠå ¶ç”Ÿæ€ä½ç‰¹å¾.

To understand the relationships among dominant species of cephalopods in offshore nor-thern South China Sea, we examined the niche characteristics of these dominant species from both spatial and temporal dimensions using the index of relative importance (IRI), the niche breadth and overlap indices based on fishery resources data from the bottom-trawl survey for four seasons during 2014-2015. The results showed that five dominant species of cephalopods were recorded for four seasons, including Loligo edulis, L. chinensis, L. beka, Sepia esculenta, and L. duvaucelii. The first two species were shared by all seasons. Compared with historical data, the composition of dominant cephalopods species had changed. The cephalopods resource exhibited obvious temporal and spatial variations. Stock density was higher in the sea area extending from the southern Hainan Island to eastern Guangdong Province than that in Beibu Gulf. The seasonal variation was characte-rized by the largest in summer but the smallest in winter. The temporal and spatial niche analysis showed that there was inconsistent in the order between temporal and spatial niche breadths for domi-nant species. L. edulis (1.32) and L. chinensis (3.90) occupied the largest temporal and spatial niche breadths, respectively. The smallest of temporal and spatial niche breadths were shown for S. esculenta (0.98) and L. duvaucelii (2.04), respectively. Though the temporal niche overlap was numerically larger than the spatial niche overlap, both of them had higher values in interspecies among L. edulis, L. chinensis, L. beka, and the lower overlap for the species pairs between L. duvaucelii and other species. The result of correlation analysis suggested that niche breadth exhibited a significant negative correlation with variation in abundance on both temporal and spatial scales. The ecological niche could reflect the tempo-spatial changes of species resource, which enriched the traditional methods of fishery communities.

Primary cutaneous zygomycosis caused by rhizomucor variabilis: a new endemic zygomycosis? A case report and review of 6 cases reported from China.

We report a case of primary cutaneous zygomycosis caused by Rhizomucor variabilis and review 6 cases reported from China that share similar features and are different from those cases caused by other species of Mucorales. It is noteworthy that all 6 of the cases were observed in 3 adjacent provinces of eastern China.

Primary cutaneous zygomycosis due to Absidia corymbifera in a patient with cutaneous T cell lymphoma.

A slowly enlarging arm ulcer appeared in a 61-year-old man with cutaneous T cell lymphoma. Skin biopsy revealed aseptate hyphae and nodular small/medium-sized pleomorphic CD4(+) T cell infiltration. Cultures yielded Absidia corymbifera which was identified by phenotypic and molecular methods. Since a thorough examination did not detect organ involvement, the patient was diagnosed as having primary cutaneous zygomycosis. This is the first case report of cutaneous zygomycosis caused by A. corymbifera in a patient with primary cutaneous CD4(+) small/medium-sized pleomorphic T-cell lymphoma. Other cases of primary cutaneous zygomycosis caused by A. corymbifera are also reviewed.

A new medium for diagnosis of dermatophyte infection.

A new medium (DBM) was compared with dermatophyte test medium (DTM) for the diagnosis of dermatophyte infection. The sensitivity was 103 cfu/mL (2 x 101 cfu/slant) for both DTM and DBM with a suspension of Trichophyton rubrum. In axenic cultures, all dermatophytes tested altered the color of both media. Although most non dermatophytic molds made a color change, it was at a slower rate. In nail samples of dermatophyte infection, all dermatophytes altered the color of both media. However, the time for discoloration was shorter with DBM than with DTM (5.83 +/- 0.39 days vs. 7.32 +/- 0.41 days, t = 2.63, P = 0.01). Most isolates of nondermatophyte also made a discoloration, but they could be distinguished from dermatophytes by their colonial diameters when the color began to change (> or = 5 mm). Our results were in good agreement with a professional laboratory of medical mycology, however, the latter is regularly able to differentiate exactly the species of the growing dermatophyte. The DBM medium is more convenient, rapid, more accurate and economical to use than DTM.

Pyoderma gangrenosum with pulmonary involvement?

Pyoderma gangrenosum is a rare, painful, noninfectious, ulcerative, reactive neutrophilic skin condition. It is characterized by ulcers that can spread quickly showing undermined violaceous borders. Since there is no single diagnostic test, early diagnosis is always challenging. The aggressive nature of classical pyoderma gangrenosum may become apparent only with time. Pulmonary involvement of pyoderma gangrenosum maybe underreported. We describe a case of classical pyoderma gangrenosum in a 65-year-old man with pulmonary involvement, who presented with a painful fluctuate nodule and ulcer with mucopurulent and hemorrhagic exudates, and with a monoclonal gammopathy, IgA type. One month later the ulcer and hemoptysis all disappeared after treatment with glucocorticosteroids. The pulmonary manifestations of pyoderma gangrenosum were also reviewed.

Genotype comparisons of strains of Candida albicans from patients with cutaneous candidiasis and vaginal candidiasis.

BACKGROUND: It is uncertain whether genotypes of Candida albicans (C. albicans) are associated with colonizing body locations or variant conditions of infection. The aim of this study was to investigate whether there are significant associations between strain genotypes and body sites of infection and to determine the potential pathogenesis of cutaneous candidiasis at multiple locations. METHODS: A total of 151 strains of C. albicans were isolated from 74 infant patients with cutaneous candidiasis and 61 female patients with vaginal candidiasis. Patients were grouped according to the body sites and underlying conditions of infection. Genotypes were identified by polymerase chain reaction (PCR) of the 25S rDNA and PCR-restriction fragment length polymorphism (RFLP) of ALT repeats digested with EcoRI and Clal. RESULTS: Ten genotypes were detected. There were significant differences in genotype frequencies between the two groups. However, we found no clear association between genotypes and the sites of cutaneous infection or the underlying conditions of vaginal candidiasis (VVC). In addition, strains of C. albicans from multiple cutaneous locations of the same patient had identical genotypes. CONCLUSIONS: Populations of C. albicans from patients with cutaneous and vaginal candidiasis were genetically different. However, the lack of genetic difference between strains from different body sites with cutaneous infections or from different underlying conditions for VVC suggests no evidence of genotype selection for different skin surfaces or patients with different underlying conditions for VVC.