The chemotactic activity of Candida albicans proteinase toward human peripheral leuko- cytes was examined by a modified Boyden chamber method.It was found that C.albicans proteinase in- duce dose-dependent chemotactic activity for neutrophils with maximal activity at 500 nmol/L(P

Objective To report a case of black-dot ringworm caused by Trichophyton tonsurans in a 3-year-old girl. Methods Lesional hair was obtained from the patient and subjected to direct microscopic examination as well as culture. Subsequently, the isolate underwent morphological, biochemical and molecular biology identification. The extracellular enzymatic activity of the isolate was analyzed. Results Microscopy revealed that the hair shaft was filled with fungal spores. Typical colony of the isolate was grayish-white with downy appearance. Slide culture showed centipede-like, lateral, rod-shaped microconidia. Urease test was positive. The amplification of ribosomal DNA (rDNA) ITS domains by PCR produced a 687 bp-sized fragment which had a 100% homology with the sequences of several Trichophyton tonsurans strains in the GenBank database. The extracellular enzymatic activity analysis showed an increase in the activity of alkaline phos-phatase, acid phosphatase, esterase (C4), β-glucosidase, leucine arylamidase, N-acetyl-β-glucosaminidase and a-mannosidase. Conclusions The pathogenic fungus is identified as Trichophyton tonsurans based on morphological and biochemical features as well as sequence of the ITS region of rDNA, and the child was diagnosed with black-dot ringworm.

Objective To study the morphological,biologic response of cultured human keratin ocytes to Candida albicans and the molecular mechanism.Methods ①A yeast form of C.albicans was added t o a monolayer of keratinocytes.The adherent organisms were observed by scanning and transmission electron mi-croscope at different incubation periods.Boiled C.albicans and latex beads of a similar size(3.2?m)were also inoculated for comparison.②The effect of supernatant from the co-culture of keratinocytes with inta ct C.albicans on keratinocyte growth was measured by the fluorescence intensity and cell count.③Keratinocytes were incubated with C.albicans or latex beads,and the level of cytok ine in the keratinocytes and supernatant were measured with enzyme -linked im munosorbent assay kits.Results①The number of adherent C.albicans increased with the lapse of time,whi le boiled C.albicans did not adhere at all.Many latex bead s adhered to the keratinocytes,and were then easily phagocytised.Fibril -like structu res stretched from the keratinocyte s adhered to the organisms or latex beads.②The conditioned medium of 50%concen tration significantly promote cell growth,while that with boiled C.albicans or latex beads moderately stimulate d keratinocyte growth.③Ker-atinocytes treated with intact C.albicans had significantly higher level of IL-1?in the supernatant but lower in the cell extract.Both TGF -?and bFGF increased either in the medi a or in the extract.Conclusion These results suggest that keratinocytes have non -specific phagocytic activ ity.C.albicans are able to adhere to ker-atinocytes and stimulate the release of various cytokines from keratinocytes,which may induce an inflammatory reaction and cell growth.

Objective To isolate and observe Pityrosporum yeasts from a patient with onychomycosis. Methods The involved nail specimens were investigated by means of culture, pathological and scanning electron microscopic examination and 20% KOH preparation. Results Physical examination showed that each finger and toe nail appeared brownish black, rough and thick, some of the fore part of the nail plate detached from the nail bed. Fingernail specimen's culture results showed that Trichophyton rubrum grew on Sabouraud's dextrose agar and Pityrosporum ovale grew on the medium containing rapeseed oil. The pathological examination revealed P.ovale yeast involvement in the fissure of the nail plate. Under the scanning electron microscopy, a lot of P.ovale yeasts with characteristic collarette structure inserted in the nail tissue was noticed. In the 20% KOH preparations of nail incubated at 56℃for 1h and stained with Quink Parker ink, spores and hyphae were identified morphologically with P.ovale and T.rubrum respectively. The patient received intermittent pulse therapy with itraconazole, the color of the nails became much brighter 1 to 2 months after the fourth cycle of therapy, but no further improvement was observed afterwards. P.ovale and T.rubrum grew again 6 months after treatment when the clippings of the fingernail were cultured. Conclusion This is the first document of onychomycosis related with P.ovale in China.

Objective To investigate the etiology of papular urticaria: is it caused only by arthropod-like insects-bite allergy, or by multiple factors such as food allergy, disturbance of gastrointestinal function and infection? Methods We searched, by computer and manually, the foreign and domestic literature related to the etiology of papular urticaria published since 1950s, and according to the methods of evidence-based medicine, systematically evaluated the evidence supporting either the insect-bite theory or the multiple factor theory. Results Twenty-nine articles ( 22 English and 7 Chinese ) supported the theory of hypersensitivity to bites from certain insects such as mosquitoes, gnats, fleas, mites, bedbugs etc. Two articles in Chinese mentioned the possibilities other than insect-bite, but the reliability was unconvincing, because the authors did not present the source of data or statistical methods used in the articles. The evidence from epidemiology, histopathology, laboratory and clinical researches all supported the insects-bite theory. No proven evidence was found supporting other aetiological hypotheses. Conclusion Our results suggest that papular urticaria is caused only by the allergy to stings or bites of arthropods, and other hypotheses still lack convincing evidence.

The effect of povidone iodine solution(PIS)on the metabolic activity of Candida albi- cans and the effect of PIS treated C.altn'cans to cultured human keratinocytes were studied by using the Alamar blue fluorescence assay.It was found that PIS inhibited the metabolic activity of Candida albi- cans with a dose-dependent manner,and that the LD_(50)of PIS for Candida albicans is 0.075%.After treating for 30 min by 2% PIS/PBS(-),Candida albicans almost lost the adherence and invasion to the cultured human keratinocytes,the wall of yeast cells became uneven and shrunken,the intracellular structures became obviously indistinct,and the yeasts could not develop to hypha form.Candida albi- cans,treated with 2% PIS in PBS(-)for 30 min or with 10% PIS Sabouraud's liquid medium for 33 hr,did not form colony when it was inoculated to Sabouraud's dextrose agar.This result suggests that the fungicidal effective of PIS is influenced by its solvent.

A 66-year-old man was admitted for a 7-day history of painful blisters and erosions in the upper lip.Real-time PCR with herpes simplex virus (HSV) type-specific primers showed that the blister fluid and crusts were positive for HSV-1,but negative for HSV-2.Observation of the blister wall with transmission electron microscopy (TEM) revealed 3 types of nucleocapsid in the karyoplast of epithelia cells,including the electron-translucent core,granular core and electron-dense core.Numerous matured viral particles with envelope were found in the cytoplasm,which were identified as HSV.The diagnosis was made as herpes simplex in the upper lip based on the above findings.PCR based molecular typing combined with observation of HSV particles via TEM may be an effective approach to the definite diagnosis of primary herpes simplex.

A strain of Prototheca species isolated from a case of meningitis was identified by routine morphologic and biochemical methods as well as amplification of the related genes, in which the 28S large-subunit (LSU) region of ribosomal RNA (rRNA) gene and intergenic space (ITS) were amplified with universal fungal primers. The small-subunit (SSU) rRNA gene was amplified with eukaryote-specific primers and Prototheca genus-specific primers. Then, compared the sequences with the ones posted on BLAST (www. ncbi. nlm. nih. gov/BLAST). The organism choice giving the closest match, up to 99%, was considered the most likely correct identification. It was found that this strain of fungus grew well at 25 ℃ or 37 ℃. Smooth,moist colonies with white color were observed on Sabouraud Dextrose Agar (SDA) and Potato Dextrose Agar (PDA). Microscopically, globular or ovoid cells, a number of round, ovoid shaped endospores could be observed. No hypha, ascus or blastic conidia was found upon cultivation on SDA. Based on the morphological characteristics, this isolate could be identified as Prototheca species. The identity with Prototheca wickerhamii was 2.9 % as demonstrated by the API 20C AUX system. Sequence analysis showed that the ITS gene was proved to be a complex structural region which was not suitable for the identification of Prototheca species, but the LSU and SSU rDNA regions showed 94% and 99.9% sequence identities with Prototheca zopfii var. hydrocarbonea (P. zopfii var. hydrocarbonea) respectively, indicating that the SSU rRNA gene sequence might be more reliable on than the LSU rRNA gene sequence for identification of Prototheca species.

Objective To examine the distribution of Malassezia species in follicular contents and perifollicular superficial skin in patients with Malassezia folliculitis and search for its causative agent. Methods A total of 120 patients with Malassezia folliculitis were investigated. Follicular lesions at three different anatomic sites were selected in each patient. Perifolliclar superficial skin specimens were taken by sterile adhesive tape, and the follicular contents of the same follicle were taken by sterile haemostatic forceps. The above specimens were cultured respectively on media containing rapeseed oil. The isolated colonies were identified by their physiological and morphological characteristics. Results Out of 319 isolates obtained from the perifollicular superficial skin, 247 isolates (77.43%) were identified as M. sympodialis, 40 isolates (12.54%) as M. furfur, 27 isolates(8.46%) as M. globosa and 5 isolates(1.57%) as M. obtusa. Out of 314 isolates obtained from follicular contents, 252 isdates(80.25%) were identified as M. globosa, 57 isolates(18.15%) as M. sympodialis, 4 isolates(1.27%) as M. furfur, and 1 isolate(0.32%) as M. obtusa. There was statistical difference in species distribution between the follicular contents and the perifolliclar superficial skin (P

Objectives To compare the difference between multipoint inoculation and routine method for isolation of pathogenic fungi from nail samples of onychomycosis,and to analyze the epidemiology of pathogenic fungi in those patients.Methods The nail clipping samples from each patient were inoculated onto the plates with Sabouraud's agar,Sabouraud's agar without cycloheximide and medium containing rapeseed oil,respectively,by an approach of at least seven inoculating points in each plate (multipoint inoculation),and onto medium slope in tubes with the same media as above mentioned (routine method).In the multipoint inoculation method,plates with more than 3 colonies were taken for further identification of pathogenic fungi based on morphological and biochemical properties.Results Based on the data from 150 samples of onychomycosis,significant differences were found between multipoint inoculation method and routine method (P