1.Random amplified polymorphic DNA combined with microfluidic chips in the identification of Malassezia species
Chinese Journal of Dermatology 2012;45(8):545-548
Objective To evaluate the performance of microfluidic chips in the identification and genotyping of Malassezia species.Methods This study included 6 reference Malassezia strains and clinical Malassezia isolates from the scrapings of patients with pityriasis versicolor and follicular contents of patients with Malassezia folliculitis.These isolates were identified by DNA sequencing,random amplified polymorphic DNA (RAPD)-PCR and microfluidic chips.Cluster analysis was carried out and tree diagrams were generated.Results A total of 83 Malassezia isolates were obtained from 72 patients with pityriasis versicolor and 11 patients with Malassezia folliculitis.Genomic DNA of most strains was successfully amplified by PCR with two primers S22 and S24,and PCR with S22 primer produced more stable and clear amplification bands than that with S24.Positive bands of different sizes were repetitively obtained by using microfluidic chips,with interspecies and intraspecies polymorphisms observed in all the strains.On the basis of DNA sequencing,microfluidic chips and RAPD-PCR could be used to successfully distinguish the following eight species,i.e.,M.furfur,M.sympodialis,M.globosa,M.pacbydermatis,M.slooffiae,M.Japonica,M.yamatoensis and M.dermatis.Conclusions As a rapid,high-throughput and high-sensitivity method,microfluidic chips combined with RAPD-PCR shows an advantage for analyzing interspecies genetic diversity,genetic relationship of Malassezia species,as well as for identifying new Malassezia species.
2.Establishment of identification database of six common dermatophytes using Biolog automatic analyzer for microbes
Yilun XIAO ; Chiyu CHEN ; Qiangqiang ZHANG
Chinese Journal of Dermatology 2010;43(5):350-353
Objective To investigate the application prospect of Biolog automatic analyzer for microbes in the identification of common dermatophytes. Methods Clinical isolates of dermatophyte were identified to species level based on phenotypes and DNA sequence. The strains of Trichophyton rubrum, Trichophyton mentagrophyte, Trichophyton tonsurans, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum were inoculated into FF microplates, and the utilization of 95 different carbon sources were recorded.The growth and reaction spectrum of these strains were described and identification database was set up. Results There was a great difference in the utilization of carbon sources among different fungal species. The utilization of raffinose could differentiate Trichophyton mentagrophyte and Trichophyton tonsurans from the other four Trichophyton. Sebacic acid could differentiate Trichophyton mentagrophyte from Trichophyton tonsurans.Meanwhile, Trichophyton rubrum could be differentiated from Microsporum gypseum, Epidermophyton floccosum and Microsporum canis by utilization of fumarate and succinate. Microsporum gypseum could be identified by use of alanine and phenylalanine. The utilization of dextrin could distinguish Epidermophyton floccosum from Microsporum canis. Conclusion The Biolog automatic analyzer for microbes has the ability to identify common dermatophytes to species level based on their specific phenotype.
3.Portable ECG measuring system with non-contact electrode.
Xudong ZHANG ; Chen LIU ; Qiangqiang CUI
Chinese Journal of Medical Instrumentation 2014;38(3):168-185
Heart disease is the major disease that threaten human health. ECG is an important tool for the diagnosis of cardiac disease. As traditional ECG measurement devices have many disadvantages, a non-contact ECG measurement system was designed. With the non-contact electrode based on capacitive coupling, the signals were collected and then they were amplified and filtered. The conditioned analog signal was converted to digital data which was sent to the mobile terminal through bluetooth. Finally, the ECG data was analyzed to extract the key ECG parameters. The results showed that the precise ECG signals can be got with the non-contact electrode and the key ECG parameters can be acquired accurately.
Electrocardiography, Ambulatory
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instrumentation
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Electrodes
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Equipment Design
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Signal Processing, Computer-Assisted
4.Establishment of a mouse model of cutaneous protothecosis
Yibin ZENG ; Ying ZHAO ; Qiangqiang ZHANG
Chinese Journal of Dermatology 2013;46(10):746-748
Objective To develop a mouse model of cutaneous protothecosis.Methods Totally,48 BALB/c mice were randomly and equally divided into four groups:high-and low-concentration immunosuppressive groups-immunosuppressed mice inoculated with P.zopfii var.portoricensis suspension of 1 × 109 and 1 × 106 colony forming units (CFU) conidia/ml respectively,high-concentration healthy group-healthy mice inoculated with P.zopfii var.portoricensis suspension of 1 × 109 CFU conidia/ml,and control group-healthy mice inoculatedwith sodium chloride physiological solution.The P.zopfii suspension or sodium chloride physiological solution was subcutaneously inoculated to the abdominal skin of mice,with the inoculation volume being 200 μl.Skin appearance at the inoculation site was observed,and four mice were sacrificed in each group on day 7,14 and 28 after the inoculation.Skin specimens were resected from the inoculation sites of mice and subjected to pathological and mycological examinations.Results Mice in the three experiment groups inoculated with the P.zopfi suspension were all infected,with the appearance of papules and abscess at the inoculation sites of all mice as well as ulcer and crusts in some mice.Meanwhile,no mice were infected in the control group.Significant differences were noted in the diameter of skin lesions between the three time points in these experiment groups (all P < 0.05),and the largest diameter of lesions was observed on day 7,which was (6.75 ± 1.09) mm in the high-concentration immunosuppressive group,(5.88 ± 1.17) mm in the low-concentration immunosuppressive group,and (5.96 ± 0.99) mm in the high-concentration healthy group.Comparisons of lesion diameter between the three experiment groups revealed a statistical difference on day 28 (F =8.91,P < 0.05),with the largest lesion diameter observed in the high-concentration immunosuppressive group (4.38 ± 0.86 mm),but no statistical difference was found on day 7 or 14 (both P > 0.05).Pathology of skin specimens consistently revealed necrosis,abscess and granuloma formation in the three experiment groups.Spores were found in the lesions of infected mice by haematoxylin-eosin staining,periodic acid-Schiff staining,and direct microscopy.Culture of tissue samples from the experiment groups grew Prototheca.Conclusion The mouse model of protothecosis can be established by subcutaneous inoculation of Prototheca suspension in the abdominal skin of healthy or immunosuppressed mice.
5.Detection of Prototheca zopfii infection in mouse skin tissue sections by using fluorescence in situ hybridization
Yuli KANG ; Ying ZHAO ; Qiangqiang ZHANG
Chinese Journal of Dermatology 2014;47(9):646-649
Objective To evaluate the feasibility to detect Prototheca in a mouse model of Prototheca zopfii cutaneous infection by using fluorescence in situ hybridization (FISH).Methods The model of Prototheca zopfii cutaneous infection was established by abdominal subcutaneous inoculation of Prototheca zopfii suspensions into 20 male BALB/c mice.Seven days after the inoculation,the mice were sacrificed,and tissue specimens were obtained from abdominal skin and subjected to microscopic examination,fungal culture and paraffin embedding.A PZ-probe was artificially synthesized and used to detect Prototheca in paraffin-embedded sections by using FISH.Moreover,both periodic acid-Schiff (PAS) and hematoxylin-eosin (HE) staining were performed to examine the paraffin-embedded sections.Skin specimens obtained from normal mice and Candida albicans-or Cryptococcus neoformans-infected mice served as the negative control.Results Clinical presentations,pathological examination and fungal culture results all confirmed the successful establishment of Prototheca zopfii skin infection model in mice.Prototheca was identified by FISH with the PZ-probe in the paraffin-embedded skin tissue sections from the murine model of Prototheca zopfii cutaneous infection,but not detected in the negative control tissue specimens,which was consistent with the results of PAS and HE staining.Conclusion FISH can be used to detect Prototheca in paraffin-embedded skin sections from the mouse model of Prototheca zopfii cutaneous infection.
6.Phaeohyphomycosis Caused by Chaetomium Globosum: First Case Report in China
Jiajun WANG ; Qiangqiang ZHANG ; Li LI
Chinese Journal of Dermatology 1994;0(05):-
A 13 year old male farmer suffered from cutaneous and nail phaeohyphomycosis for five years is reported in this paper. The lesions were dull red, nodules and well defined plaques with ulcerations, mainly on the face, extremities, palmar and plantar surfaces and buttocks. Some of them were covered with thick greyish black crusts. General examination did not reveal abnormal findings except the skin lesions. Histopathology showed granulomatous response with numerous light brown septate branching hyphae. The colonies were greyish brown on SDA and PDA at 25℃ and 37℃ with brownish black ascomata. The ioslated strain was identified as Chaetomium globosum based on the morphological features of ascomata, ascomal hairs and ascospores.
7.Skin Verrucous Hyperplasia Caused b y Epidermophyton floccosum and Candida ciferrii:a Case Report
Weimin SHEN ; Jiajun WANG ; Qiangqiang ZHANG
Chinese Journal of Dermatology 1994;0(05):-
Several years after trauma,a patien t suffered from skin verrucous hyperplasia for more than 30years,accompanied by ulcer occasio nally,on the feet,ankles and legs su ccessively.Mycological examinati on(9times)had been done before treatment.Slig ht septate hyphae and /or spores were demonstrated by direct mi-croscopy(5times);and yellowish green colony grew on S abouraud agar at 25℃for 2times,it wa s identified as Epidermophyton floccosum.Yeast -like colony grew on Sabourau d agar at 25℃for 5times,it was identi fied as Candida ciferrii by API.After treatment,Candida ciferrii could still be detected by mycologic al examination(6times),but no Epidermophyton floccosum was found.Slight septate hyphae were demonstrated in stratum spinosum,stratum granulosum and stratum corneum by histopathological examination.Isolated or clustered blastospores,spores and chlamydospores were demonstrated in stratum c orneum by histopathological examin ation.Therefore,it was concluded that the skin verrucous hyperplasia in this c ase is caused by mixed infection of Epidermophyton floccosum and Candida ciferrii.The patient was treated with flucon azole capsule 50mg daily for5weeks,followed by terbinafine tab let 250mg daily for 36weeks,and then250mg twice daily for 18weeks.In the 5th week of terbinafine therapy,a part of the lesions on the shin of left leg healed.No further therapeutic effect was observed.
8.Discrepancy of clinical isolates of Candida rugosa between genotype and phen otype
Liping ZHU ; Qiangqiang ZHANG ; Yaozhong SHI
Chinese Journal of Infectious Diseases 2001;0(05):-
Objective To compare discrepancy between genotype and pheotype of th e clinical isolates of Candida rugosa. Methods The fung us-specific universal prim ers derived from the internal transcribed spacer (ITS) region of fungal rDNA wer e used for amplification. Genomic DNA purified from the thirteen clinical isolat es of non-C. Albicans was amplified by PCR. The purified PCR product was cloned into pBluescript Ⅱ KS(+) T vector and sequenced by Sanger's dideoxy chain terminatio n composition method. The two isolates were evaluated against CHROM Candida medi um and API 20C AUX. Results The two isolates of Candida rugosa were evaluated as Candida tropicalis by CHROM Candida medium and API 20C AUX. Conclusio ns Discrep ancy between genotype and phenotype of the two clinical isolates of Candida ru gosa was confirmed.
9.PCR fingerprinting discriminating between Candida albicans and Candida dubliniensis
Liping ZHU ; Qiangqiang ZHANG ; Huafei GONG
Chinese Journal of Infectious Diseases 1997;0(04):-
Objective To develop a rapid PCR fingerprinting for discriminating between Candida albicans and Candida dubliniensis isolates. Methods Genomic DNA purified from the two species was amplified by single primer PCR. Oligonucleotide of the minisatellite-specific core sequence of the wild-type phage M13 (5′-GAGGGTGGCGGTTCT-3′) was used as primer and the amplified products were analyzed by gel electrophoresis and microfluidic DNA chip assays. Results Of 17 candida isolates, the PCR fingerprinting generated five strain-specific bands for C. albicans and C. dubliniensis respectively, allowing identification to species level between them. The other bands were minor different in their species. By microfluidic DNA chip, the DNA fragments in size of amplified products for the C. dubliniensis were 960,1177,1297,1495,1797 bp and for the C. albicans 653,1323,1531,2021,2875 bp. Conclusions C. albicans and C. dubliniensis have distinguishable pattern by PCR fingerprinting using the single primer. The microfluidic DNA chip is proposed here as a simple, rapid and highly reproducible tool, especially for the epidemiological investigation.
10.Advances in diagnosis and treatment of the gallbladder polypoid lesions
Qiangqiang XIE ; Wenxiang ZHANG ; Wenyu GAO ; Yanbo MA
Chinese Journal of Postgraduates of Medicine 2017;40(3):275-277
With the continuous improvement of various imaging techniques, the morbidity of polypoid lesions in gallbladder is increasing year by year. However, owing to the lack of effective means of diagnosis before undergoing the surgery, there is a large number of patients who do not have definite indications of surgery for prophylactic cholecystectomy. Therefore, this text will carry out a comprehensive narration of the imaging features, epidemiological characteristics and pathological types about the polypoid lesions in gallbladder, summarizing the experience of diagnosis and treatment of the disease, helping the option in clinical treatments.