Three-dimensional finite element analysis of the influence of implant site and axial direction on the immediate weight bearing stress of central incisors in different alveolar fossa shapes / 口腔医学

Objective@#To analyze and investigate the effects of implant location and axial direction on the stress distribution of implants, abutments, central screws, and crowns during immediate loading of maxillary mesial incisors with different alveolar fossa morphology based on three-dimensional finite element method.@*Methods@#Referring to the oral CBCT images of a healthy adult, a three-dimensional finite element model was established for immediate implant loading of maxillary central incisors with three alveolar fossa morphs: labial, intermediate, and palatal; different implant sites(apical site, palatal/labial site) and axes(tooth long axis, alveolar bone long axis) were simulated; the established model was loaded with a force of 100 N. ANSYS software was applied to analyze the stress values of the implants, abutments, central screwss, and crownss. @*Results@#The 3D finite element models of 12 maxillary central incisors with different alveolar sockets were successfully established;the implants and their superstructures were least stressed when the maxillary central incisors with partial labial and partial palatal shape were placed along the long axis of the alveolar bone in the palatal/labial position for immediate implant loading;the implants and their superstructures were least stressed when the maxillary central incisors with central shape were placed along the long axis of the tooth in the palatal position for immediate implant loading. The implant and its superstructure were subjected to the least stress when the implant was placed along the long axis of the tooth in the immediate loading position. @*Conclusion@#The bio-mechanical characteristics of the implant and its superstructure are influenced by the different socket morphology, implantation sites and axes. Therefore, in clinical practice, different implantation axes and implantation sites should be developed for different socket morphs.

Effects of Implant Sites and Axial Direction on Stress of Maxillary Central Incisors with Immediate Implantation under Immediate Weight-Bearing: A Three-Dimensional Finite Element Analysis / 医用生物力学

Objective To investigate the influence of implant location and axial direction on stress distributions at the implant bone interface of maxillary central incisors with different alveolar fossa morphology by immediate implantation under immediate weight-bearing. Methods With reference to dental cone beam computed tomography (CBCT) image data from a healthy adult, the three-dimensional ( 3D) finite element models of maxillary central incisors with three types of alveolar fossa ( buccal, mediate, and palatal type) by immediate implatation under immediate weight-bearing were established. Different implant sites ( apical site, palatal / labial site) and axial directions (long axis of the tooth, long axis of the alveolar bone) were simulated. The established models were subjected to 100 N force at different angles (0°, 30°, 45°, 60°, 90°). The stresses in the alveolar bone around the implant were analyzed by the ANSYS software. Results Twelve 3D finite element models of maxillary central incisors with different alveolar fossa morphology by immediate implantation under immediate weight-bearing were successfully established. When alveolar fossa with buccal and mediate shape was applied with immediate implantation under immediate weight-bearing, it was easier to obtain good biomechanical properties of the implant-bone interface when implants were placed at palatal site along long axis of the alveolar bone. When alveolar fossa with palatal shape was applied with immediate implantation under immediate weight bearing, the equivalent stresses on peri-implant alveolar bone were much smaller than those on apical site, regardless of whether the implant was placed along long axis of the tooth or the long axis of the alveolar bone. Conclusions Different alveolar fossa morphology, implant location and axial direction will affect characteristics of implant-bone interface of maxillary central incisors with immediate implantation under immediateweight-bearing. In clinical practice, surgical planning on different axial direction and location of implantation should be developed for alveolar fossa with different morphology.

Clinical efficacy of triamcinolone acetonide combined with tanshinone ⅡA injection in the treatment of OSF and the effect on serum TGF-β1 and IL-6 / 国际检验医学杂志

Objective To investigate the effects of triamcinolone acetonide combined with tanshinone ⅡA (Monomer of tanshinone)injection on oral submucous fibrosis(OSF)and the effect of serum TGF-β1 and IL-6 on patients.Methods 92 patients with OSF,w ho came to the hospital for treatment from April 2013 to April 2016,were selected and randomly divided into control group(46 cases)and experimental group(46 ca-ses).They were respectively treated with triamcinolone acetonide and triamcinolone acetonide combined with tanshinone injection.The two groups were treated for 3 courses and were followed up for 12 months.The VAS scores and mouth opening were compared between the two groups before the treatment and 2,4,6,and 12 months after the treatment,The serum TGF-β1,IL-6,lesion area and the changes of quality of life oral health impact scale(OHIP-14)scores of two groups were compared before and after treatment.Results 6 months after follow-up,the maximum mouth opening of the two groups was significantly increased than that before treatment,and improvement speed and improvement degree of the experimental group were better than those of the control group(P<0.05).After 2,4,6 and 12 months follow-up,the VAS scores of the two groups were significantly lower than those before treatment,and the experimental group were significantly lower than those of the control group(P<0.05),but the VAS score of two groups after 12 months increased than that after 6 months,and the control group was more obvious(P<0.05).After treatment,the levels of TGF-β1 and IL-6 of the experimental group were significantly lower than those of the control group and before the treat-ment(P<0.05);After treatment,the lesion area of the experimental group was significantly lower than that of the control group,and the OHIP-14 score was significantly higher than that of the control group,and the difference was significant compared with this group before treatment(P<0.05).Conclusion The local injec-tion treatment of triamcinolone and tanshinone injection has godd efficacy of OSF patients,and significantly re-duces the levels of TGF-β1 and IL-6 in serum.

Cutaneous mucormycosis caused by Mucor irregularis: a case report / 中华皮肤科杂志

A 39-year-old female patient presented with a painful plaque with ulcers on the right cheek for 2 months.She had acute myeloid leukemia for 1 year.After treatment,the patient achieved remission,but experienced recurrence half a year prior to the presentation.Skin examination showed a violaceous plaque measuring 5 cm × 5 cm in size on the right cheek with erosions and ulcers in the center,whose surface was covered with yellowish brown crusts.Granulation tissues were observed on the plaque,and yellow pus was exuded after the crusts were removed.The boundary of the plaque was sharp and slightly elevated,and there was obvious tenderness on palpation.Laboratory examination revealed increased white blood cell (WBC,28.75 × 109/L) and lymphocyte counts (27.17 × 109/L),but decreased neutrophil (1.05 × 109/L) and red blood cell counts (2.20 × 1012/L),hemoglobin level (69 g/L) and platelet count (84 × 109/L) in the peripheral blood.The hepatic and renal function,electrolyte level and electrocardiogram were normal.Hematoxylin and eosin (HE) staining and periodic acid-Schiff staining of the lesion showed a large number of lymphocytes and histiocytes infiltrating in the dermis and broad aseptate hyphae.The fungal microculture yielded broad hyalinea septate hyphae,fungal rhizoids,stolons and spherical sporangia.The isolated fungus was identified as Mucor irregularis by using molecular biology techniques.The patient was diagnosed with primary cutaneous mucormycosis caused by Mucor irregularis complicated by acute myeloid leukemia.Then,the patient was treated with oral hydroxyurea at a dose of 0.5 g thrice a day,a single-dose intravenous infusion of 4 units of red blood cell suspension,and intravenous drip infusion of amphotericin B at an initial dose of 5 mg/d,which increased by 5 mg every day until 25 mg/d (about 0.5 mg· kg-1· d-1).After the treatment,the lesion gradually became fiat and smaller.After 12-day treatment,the patient was discharged because of a certain reason,and finally lost to follow-up.

Identification and antimicrobial susceptibility of 52 pathogenic fungi causing candidemia in Nanchang City of Jiangxi Province / 中国感染控制杂志

Objective To explore the constitute and antimicrobial susceptibility of pathogenic fungi causing candidemia in Nanchang City of Jiangxi Province.Methods Candida spp.isolated from blood specimens of patients at a hospital in Nanchang in March-October 2015 were collected, fungal strains were identified by amplifying the internal transcribed spacer (ITS) and large ribosomal subunit (D1/D2 region of 26rRNA), antifungal susceptibility of fungi was detected.Results A total of 1 332 positive blood culture specimens were collected, including 74 fungal positive specimens, accounting for 5.56％, 52 strains of Candida spp.were obtained, most were Candida tropicalis (n=17,32.69％),followed by Candida albicans(n=16, 30.77％) and Candida parapsilosis complex (n=16, 30.77％).Identification results of ITS and D1/D2 region were identical.52 strains of Candida spp.were sensitive to both micafungin and caspofungin, epidemiological cutoff value(ECV) of amphotericin B showed that 52 strains were all wild type.Resistance rates of Candida tropicalis to fluconazole and voriconazole were 29.41％ and 17.64％ respectively, ECV of itraconazole and posaconazole showed that wild type accounted for 82.35％ and 94.12％ respectively;resistance rates of Candida albicans to fluconazol and voriconazole were 93.75％ and 81.25％ respectively, ECV of itraconazole and posaconazole showed that wild type accounted for 75.00％ and 81.25％ respectively;Candida parapsilosis complex strains were sensitive to both fluconazole and voriconazole, ECV of itraconazole and posaconazole showed that all were wild type;all Candida glabrata strains had intermediate resistance rates to fluconazole, ECV of voriconazole, itraconazole, and posaconazole showed that wild type accounted for 66.67％, 100.00％, and 100.00％ respectively.Conclusion Candida tropicalis is the most common pathogenic fungus causing candidemia in Nanchang of Jiangxi, followed by Candida albicans and Candida parapsilosis complex.Azole, echinocandin, and amphotericin B are still first-line antifungal agents.

Rhizopus arrihizus swollen spores induce mice dendritic cells to Th1 and Th17 differentiation / 中华微生物学和免疫学杂志

Objective To study the mechanism of adaptive immunity against Rhizopus arrihizus (R. arrihizus) infections. Methods Bone marrow derived dendritic cells (BMDCs) were separated from C57BL/6 mice and Card9-/- mice and then were cultured in vitro. Resting spores and swollen spores of R. arrihizus were in vitro co-cultured with BMDCs with or without Syk inhibition. Secretion of cytokines ( IL-23, IL-1βand IL-12) was analyzed by ELISA after 24 hours of culture. Na?ve T cells derived from C57BL/6 mice were in vitro co-cultured with spore-stimulated BMDCs for four days. Levels of IL-17A and IFN-γ in supernatants of cell culture were analyzed by ELISA. Flow cytometry was performed to analyze T cell differ-entiation. Confocal microscopy was used to observe the images of stained β-glucan on the surface of resting and swollen spores. Swollen spores were co-cultured with Dectin-1, Dectin-2, TLR2 and mannose receptor ( MMR) , and the binding results were analyzed by flow cytometry. Results Swollen spores but resting spores could induce the maturation of BMDCs and promote the secretion of cytokines (IL-23, IL-1βand IL-12). Co-culturing T cells with swollen spore-stimulated BMDCs enhanced their differentiation to Th17 and Th1. In addition, swollen spores promoted the secretion of Th1-related cytokine ( IFN-γ) and Th17-related cytokine (IL-17A). Adding Syk inhibitor to Card9-/-BMDCs or wild type BMDCs significantly inhibited the secretion of cytokines and T cell differentiation, especially in the Card9-/- group. β-glucan was overserved on the surface of swollen spores, but not on resting spores. On the surface of swollen spores existed pathogen associated molecular patterns ( PAMPs) that could bind with Dectin-1 and TLR2. Conclusion Swollen spores of R. arrihizus could active BMDCs to secrete cytokines of IL-23, IL-1β and IL-12 and trigger T cell responses in vitro. The possible mechanism might be associated with β-glucan exposed on the surface of swollen spores that binds with Dectin-1. The responses between BMDCs and R. arrihizus are Syk-Card9-dependent.

Th and Treg response induced by Aspergillus fumigatus pulsed dendritic cells in vitro / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Dendritic cells (DCs) can recognize the pathogen-associated molecular patterns (PAMP) of Aspergillus fumigatus (A. fumigatus), activating the immune response. During A. fumigatus infection, a Th and Treg response induced in the fungi-pulsed DCs is not yet well understood.</p><p><b>METHODS</b>In this study, bone marrow-derived dendritic cells (BMDCs) were separated and proliferated from C57BL/6 mice. A. fumigatus pulsed DCs were generated and cultured with CD4(+) T cells derived from the spleen of C57BL/6 mice in vitro. CD4(+) T cells differentiation after co-culture were analyzed by flow cytometry, ELISA, and real-time PCR analysis.</p><p><b>RESULTS</b>The A. fumigatus pulsed DCs exhibited increased Th1 and Treg frequency, Th1-related cytokines (IFN-γ and IL-12), Treg-related cytokines (TGF-β) and T-bet, and Foxp3 mRNA levels compared with the control group. There was no significant difference between A. fumigatus pulsed DCs group and the control group about Th17 and Th2 frequency.</p><p><b>CONCLUSIONS</b>The inactivated conidia of A. fumigatus were able to activate BMDCs and made them capable of triggering T cell responses in vitro. A. fumigatus loaded DCs was a weak inducer of Th17 and Th2, but induced a strong Th1 and Treg response.</p>

The application of Real-time PCR in invasive aspergillosis diagnosis / 中华检验医学杂志

Objective To investigate the value of Real-time PCR in the diagnosis of invasive aspergillosis(IA) and to compare it with galactomannan antigen assays.Methods A retrospective study was performed on 110 episodes of hospitalization of 88 patients who were at risk of invasive aspergillosis at Peking University First and Renmin Hospital from May 2008 to December 2010.23 cases with diagnosis and clinical diagnosis IA were classified as infection group and 87 cases with suspected diagnosis and non-IA were classified as non-infeciton group according to the international criterion.Real-time PCR and gaiactomannan antigen detections were performed on 257 serum samples.A receiver operating characteristic curve (ROC)was developed based on the quantitative cycle numbers and an optimal cut off value of quantification cycle (Cq) was determined.The sensitivity (Se),specificity (Sp),positive predictive value (PPV) and negative predictive value (NPV) were calculated under different considerations among which McNemar chi-square tests were used for statistical analyze.Results The area under ROC curve of Real-time PCR for the diagnosis of IA was 0.91 (95％ CI:0.825-0.995) and the optimal cut off value of Cq was 39.45.The Se and Sp of one positive PCR,two positive PCR,one positive GM and two positive GM were 87.0％,79.3％ ; 58.3％,97.8％ ; 78.3％,63.2％ ; and 58.3％,82.6％,respectively.When one positive PCR was considered as the diagnostic criterion of IA,Real-time PCR was able to diagnose 100％ and 84.2％ of proven and probable IA cases,respectively.The Sp of one/two positive PCR were statistically higher than one/two positive GM (P ＜ 0.05),respectively.The Sp of two positive PCR was statistically higher than one positive PCR (P ＜0.05).The Se and Sp were 65.2％,89.7％ and 100％,52.3％ for one positive PCR combined one positive GM and one PCR or GM positive,respectively.Conclusions Real-time PCR assays have better sensitivities and specificities than GM in the diagnosis of invasive aspergillosis.When two PCR positive were considered,better specificity and positive predictive value were achieved.

Effects of U0126 on growth and activation of mitogen-activated protein kinases in Aspergillus fumigatus / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Invasive aspergillosis (IA), which is mainly caused by Aspergillus fumigatus (A. fumigatus), is a major cause of morbidity and mortality in immunocompromised patients. Despite considerable progress in currently available antifungals the mortality still remains high in critically ill patients. U0126 which is a highly selective inhibitor of MEK1 and MEK2 in the RAF/MEK/ERK pathway in mammalian cells has been demonstrated to have an anti-proliferative role in cancer cells. The purpose of this study was to explore the role of U0126 on growth inhibition and activation of mitogen-activated protein kinases (MAPKs) in A. fumigatus.</p><p><b>METHODS</b>Germination percentage and hyphae growth in A. fumigatus treated with U0126 were observed and compared with untreated controls. Western blotting analysis was used to detect changes in activation of SakA, MpkA and MpkB.</p><p><b>RESULTS</b>U0126 inhibited germination and hyphae growth in A. fumigatus and enhanced the phosphorylation of SakA and MpkA under oxidative stress. U0126 at 10 µmol/L did not block the activation of MpkB during nitrogen starvation stress.</p><p><b>CONCLUSION</b>U0126 shows promise as an antifungal candidate and the MAPK pathway may be a possible antifungal drug target for A. fumigatus.</p>

Application of PCR combined with reverse line blot assay in detection and identification of common pathogenic Aspergillus in fungal sinusitis / 中华病理学杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of PCR/reverse line blot hybridization (RLB) assay in the detection and identification of clinical pathogens in fungal sinusitis (FS).</p><p><b>METHODS</b>Twenty-six formalin-fixed and paraffin-embedded tissues and 8 fresh tissues of FS were collected from Beijing Tongren Hospital, Capital Medical University from May 2009 to February 2010. Pathological examination, fungal culture and ITS2 region sequencing were carried out. The DNA of all samples was extracted by standard procedure and fungal universal primers ITS3 and ITS4 were used for PCR amplification of all tissues. Then the amplified products were used for RLB with five fungal species-specific probes. The results of PCR/RLB were compared with ITS region sequencing, fungal culture and pathological examination.</p><p><b>RESULTS</b>For the biopsy tissues, fungal cultures were positive in 14 cases (41.2%); pathologic examination demonstrated fungal hyphae in all cases; ITS2 region sequencing was successful in 16 cases (47.1%); PCR/RLB showed A. flavus in 14 cases, A. fumigatus in 10 cases, A. niger in four cases, A. nidulans in one case, A. flavus and A. fumigatus in three cases, and A. fumigatus and A. niger in two cases.</p><p><b>CONCLUSIONS</b>The PCR/RLB assay is suitable for rapid and accurate detection and identification of the pathogenic fungus of FS. Compared with the conventional fungal culture and microscopy, pathologic examination and DNA sequencing, the PCR/RLB has the advantages of more economy, time saving, and higher sensitivity, specificity and throughput.</p>

The centric relation-maximum intercuspation discrepancy in adult angle's class II pretreatment patients / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This study investigates the differences in condylar position between centric relation (CR) and maximum intercuspation (MI) in Angle's Class II orthodontic patients before treatment.</p><p><b>METHODS</b>80 cases, who were Angle's Class II pretreatment patients, and 50 cases, who were normal(ideal) occlusion were accepted. Dental casts were mounted on Panadent articulator with CR bite record, taken by bilateral manipulation and load testing. The differences in condylar position between CR and MI in all three spatial planes were measured using the Panadent condylar position indication (CPI).</p><p><b>RESULTS</b>(1) The positive rate of CR-MI discrepancy was 92.50%(74 cases) in the group of Angle's Class II malocclusion and 10.00% (5 cases) in the group of normal occlusion(P< 0.001). 2)74.32% (55 cases) CR-MI discrepancy in 74 cases in the group of Angle's Class II pretreatment patients were coincidence discrepancy. (3)91.25% patients in the group of Angle's Class 11 malocclusion and 66.00% in the group of normal occlusion present occlusion interferences which located at the posterior teeth.</p><p><b>CONCLUSION</b>The results suggested that orthodontists should be aware of a high incidence of condylar displacement in Angle's Class ii pretreatment patients, and measure condylar displacement before the start of comprehensive orthodontic treatment to unmask real jaw relationships and avoid possible misdiagnoses.</p>

Identification of Peudallescheria boydii/Scedosporium apiospermum dinical isolates by sequence differences of ITS and TUB / 中华检验医学杂志

ObjectiveTore-identifyfifteenclinical Pseudallescheriaboydii/Scedosporium apiospermum isolates by the sequence difference of ITS rDNA and partial β-tubulin gene (TUB) and thus understand thepathogenicstrain typesfor guiding theclinicaltreatment.MethodsMorphological appearances,D-ribose assimilation and sequencing of ITS and TUB were used to re-identify the fifteen clinical strains of Pseudallescheria boydii/Scedosporium apiospermum.The sequences of ITS and TUB were analyzed with Clustal X and MEGA 4 software.Results No difference of morphological appearances was found in the fifteen strains.Cleistothecium was observed in one isolate.All the strains were D-ribose assimilation positive.The clinical strains were re-identified as P.boydii species complex by the CBS database (http://www.cbs.knaw.nl).ElevenstrainswereP.boydiiandfourstrainswereS.apiospermum respectively.Conclusions P.boydii and S.apiospermum cannot be identified correcdy by the time-consuming conventional morphological method and biochemical characteristics.The study recommend that the clinical isolates of P.boydii and S.apiospermum should be identified utilizing a combination of traditional phenotype method and molecular biotechnology.

Susceptibility testing of Aspergillus biofilms against common antifungal drugs and a preliminary study on molecular mechanisms of antifungal drug resistance in Aspergillus biofilms / 中华皮肤科杂志

Objective To explore the susceptibility of Aspergillus biofilms to common antifungal drugs and molecular mechanisms of antifungal drug resistance of Aspergillus biofilms. Methods The susceptibility of planktonic spores of 22 clinical isolates of Aspergillus spp. to amphotericin B, caspofungin and voriconazole was evaluated by a standard broth microdilution method. Meanwhile, in vitro model of Aspergillus spp. biofilm was established for the 22 isolates, then the susceptibility of Aspergillus spp. biofilm to amphotericin B, caspofungin and voriconazole was evaluated by a method for antifungal susceptibility testing combined with colonmetric XTT-reduction assay. In addition, real-time reverse transcription (RT)-PCR was performed to determine the relative expressions of drug efflux pump genes and azole target enzyme genes during the formation of Aspergillus spp. biofilms. Results In terms of planktonic spores of Aspergillus spp., the- minimal inhibitory concentration (MIC) range was 0.5 to 2 mg/L for amphotericin B, 0.5 to 1 mg/L for voriconazole, and the minimal effective concentration (MEC) range was 0.125 to 0.25 mg/L for caspofungin. As far as Aspergillus spp.biofilms was concerned, the sessile minimum concentration required to inhibit the growth of 50% organisms (SMIC50) and 80% organisms (SMIC80) ranged from 2 to > 32 mg/L and from 8 to > 32 mg/L, respectively, for amphotericin B, from 32 to > 256 mg/L and from 256 to >256 mg/L respectively for caspofungin, from 4 to >256 mg/L and from 32 to > 256 mg/L, respectively for voriconazole. During the formation of Aspergillus spp.biofilms, no change was observed for the expression of any of the 7 tested drug efflux pump genes or azole target enzyme genes at 4 hours, while a significant increase was noted in the expression of AfuMDRl, CYP51B and CYP51A genes at 8 hours, as well as in the expression of AfuMDRl, AfuMDR2, AfuMDR4, CYP51A,CYP51B at 12, 16 and 24 hours. Of these genes, CYP51A showed the strongest increase in expression at the above 4 time points. The expression of AfuMDR3 and atrF experienced no significant change during the formation of Aspergillus spp. biofilms. Conclusions Compared to planktonic spores, Aspergillus spp. biofilms exhibit a decreased susceptibility to amphotericin B, caspofungin and voriconazole. After the formation of biofilms, the expression of drug efflux pump genes and azole target enzyme genes is elevated in Aspergillus spp.

Molecular mechanisms of cross-resistance to azole antifungal agents in a clinical isolate of Aspergillus fumigatus: a preliminary study / 中华皮肤科杂志

Objective To investigate the molecular mechanisms of cross-resistance to azoles in a clinical isolate of Aspergillus fumigatus. Methods A. fumigatus was isolated from a patient with invasive aspergillosis.Clinical Laboratory Standard Institute M38-A2 broth microdilution method and E-test method were used to determine the minimum inhibitory concentrations (MICs) or minimum effective concentration (MEC) of itraconazole, voriconazole, amphotericin B, posaconazole and caspofungin for the A. fumigatus isolate. DNA was extracted from the isolate and subjected to the amplification of cyp51A gene encoding the target enzyme of azole antifungal agents followed by sequence analysis. Results The broth microdilution test showed that the MEC of caspofungin was 0.5 mg/L, and MICs of itraconazole, voriconazole and amphotericin B were ≥ 16 mg/L,8 mg/L and 1 mg/L, respectively, for this isolate; while E-test assay revealed that the MICs of caspofungin,itraconazole, voriconazole, amphotericin B and posaconazole were 0.047 mg/L, ≥32 mg/L,≥32 mg/L, 12 mg/L and ≥32 mg/L, respectively. Sequence analysis showed an insertion of a 34-bp tandem sequence in the promoter region of the cyp51A gene as well as a T364A point mutation causing the substitution of leucine 98 (L98H). In addition, there were some other mutations in the cyp51A gene of this isolate, such as A137T,G585A, C814A, G836C, T991C and A1350G, which could result in corresponding amino acid substitutions.Conclusions An A. fumigatus strain with cross-resistance to azole antifungal agents is isolated. There is an insertion of a 34-bp tandem sequence into the promoter region as well as a T364A point mutation in the cyp51A gene, which contribute to the cross resistance to azole antifungal agents including itraconazole, voriconazole,and posaconazole. In addition, other mutations causing amino acid substitutions have also been detected in the cyp51 A gene of this isolate.

Two cases of tinea caused by Microsporum gyeum and their pathogenic analysis / 中华皮肤科杂志

Two patients were admitted to the hospital for 2-month history of pruritic eruptions on the forehead and 2-week history of pruritie eruptions on the leg, respectively. Both patients had a history of pet contact. Topical application of glucocorticoids did not work well. Dermatological examination revealed a patch measuring 5 cm ×6 cm on the forehead of one patient and a patch measuring 2 cm × 3 cm on the leg of the other patient. Both patches were surrounded by red papules and scaling. Microscopic examination of skin scales revealed hyphae and chain-like spores, and culture of skin scales grew Microsporum gyeum. Both the isolates of Microsporum gyeum were sensitive to ketoconazole, miconazole, bifonazole, terbinafine, and voriconazole. Both patients were healed after treatment with oral terbinafine and topical ciclopirox olamine.

Dexamethasone increases susceptibility of Aspergillus fumigatus to hydrogen peroxide via down-regulation of Afyap1 gene expression in vitro / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Glucocorticoid is speculated to be able to have Aspergillus fumigatus (A. fumigatus) being more susceptible to reactive oxygen species (ROS) by inhibiting Afyap1, the transcription factor activating protein-1 (AP-1) homologue in A. fumigatus, which may provide a clue to expand the clinical use of glucocorticoid in patients with fungal infections. In this study, we used dexamethasone to determine the direct effect on oxidative killing susceptibility of A. fumigatus in vitro, as well as the expression level of Afyap1 gene and its target genes (catalase and superoxide dismutase (SOD) genes).</p><p><b>METHODS</b>A. fumigatus spores were treated with different concentrations (0, 0.02, 0.2 mg/ml) of glucocorticoids and assigned to four groups (A: 0.5 hour, B: 2 hours, C: 7 hours, D: 16 hours) according to the time of treatment. The H2O2 oxidative killing assay was done, using the standard method-spot test, in each group of A. fumigatus. We measured the oxidative killing susceptibility as well as the expression level of the gene Afyap1, CATA, SOD1 and SOD2 in A. fumigatus at each group. The antifungal susceptibility to itraconazole and amphotericin B in each group of A. fumigatus was also measured with M38-A2 method.</p><p><b>RESULTS</b>The oxidative killing susceptibility of A. fumigatus was increased, consistent with the reduction of Afyap1, CATA, SOD1 and SOD2 gene expression level after being treated with dexamethasone for 0.5 hours. However, these observations were disappeared along with being treated for longer time. The antifungal susceptibility to itraconazole and amphotericin B in the A. fumigatus strains treated with dexamethasone indicated no change, compared with those without dexamethasone treatment.</p><p><b>CONCLUSION</b>Dexamethasone can have A. fumigatus being more susceptible to ROS when treated for shorter period (0.5 to 2 hours) via the reduction of Afyap1 gene expression as well as the down-stream enzyme-coding gene expression.</p>

In vitro susceptibility testing of 16 strains of Exophiala dermatitidis to 6 commonly used antifungal agents / 中华皮肤科杂志

Objective To investigate the in vitro susceptibility of 16 strains of Exophiala dermatitidis to 6 commonly used antifungal agents. Methods The Glinical and Laboratory Standards Institute (CLSI)M27-A2 protocol was carried out to determine the MIGs of terbinafine (TRB), itraconazole (ITC), amphotericin B (AMB), fluconazole (FLC), voriconazole (VRC), and caspofungin (GAS) to 16 strains of E. dermatitidis, and E-test was performed to determine those of VRG, ITC and AMB. Besides, the minimal fungicidal concentrations (MFGs) of the above antifungal agents to the 16 strains of E. dermatitidis were further assessed.The activity of TRB in combination with ITC and VRG against E. dermatitidis was also estimated. Results The MIC ranges of TRB, VRC, ITC, AMB, FLC, and CAS were 0.125 - 0.25 mg/L, 0.25 - 0.5 mg/L, 2.0 mg/L,2.0 mg/L, 16 - 32 mg/L and 16 - 64 mg/L respectively as shown by M27-A2 microdilution assay, while the MIC ranges of VRG, ITG and AMB, as determined by E-test, were 0.032 - 0.094 mg/L, 0.047 - 0.5 mg/L and 0.125 - 3.0 mg/L, respectively. The MFC ranges of TRB, VRC, ITG, AMB and FLG were 0.125 - 0.5 mg/L,0.25 - 0.5 mg/L, 2.0 - 4.0 mg/L, 2.0 - 4.0 mg/L and 16 - 64 mg/L, respectively. No synergism in the acitivity against E. dermatitidis was observed for the combination of TBR with ITC or VRC. Conclusion E. dermatitidis is susceptible to TRB, ITC, AMB, and VRC, but less sensitive to both FLC and GAS.

Relationship between antifungal resistance of fluconazole resistant Candida albicans and mutations in ERG11 gene / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The cytochrome P450 lanosterol 14alpha-demethylase (Erg11p) encoded by ERG11 gene is the primary target for azole antifungals. Changes in azole affinity of this enzyme caused by amino acid substitutions have been reported as a mechanism of azole antifungal resistance. This study aimed to investigate the relationship between amino acid substitutions in Erg11p from fluconazole resistant Candida albicans (C. albicans) isolates and their cross-resistance to azoles.</p><p><b>METHODS</b>Mutations in ERG11 gene were screened in 10 clinical isolates of fluconazole resistant C. albicans strains. DNA sequence of ERG11 was determined by PCR based DNA sequencing.</p><p><b>RESULTS</b>In the 10 isolates, 19 types of amino acid substitutions were found, of which 10 substitutions (F72S, F103L, F145I, F198L, G206D, G227D, N349S, F416S, F422L and T482A) have not been reported previously. Mutations in ERG11 gene were detected in 9 isolates of fluconazole resistant C. albicans, but were not detected in 1 isolate.</p><p><b>CONCLUSIONS</b>Although no definite correlation was found between the type of amino acid substitutions in Erg11p and the phenotype of cross-resistance to azoles, the substitutions F72S, F145I and G227D in our study may be highly associated with resistance to azoles because of their special location in Erg11p.</p>

Establishment of an animal model of dermatophytosis and evaluation of the antifungal efficacy on dermatophytosis with this model / 中华皮肤科杂志

Objective To establish an animal model of dermatophytosis and to evaluate antifungal efficacy on dermatophytosis with this model. Methods Animal models of dermatophytosis were established by inoculating dermatophyte suspension onto abraded skin on the back of guinea pigs. Thirty- eight healthy guinea pigs were randomly and equally divided into 2 groups, namely, Trichophyton mentagrophytes group (infected with T. mentagrophytes), and Microsporum canis group (infected with M. canis), and each group was classified into three subgroups, i.e., itraconazole group treated with oral itraconazole of 4 mg per kilogram body weight per day from day 0 to day 14 after infection, terbinafine group treated with oral terbinafine of 5 mg per kilogram body weight per day from day 0 to day 14 after infection, and untreated group receiving no therapy. The therapeutic effect was evaluated according to skin lesion score and fungal examination results on day 8, 11 and 14 after infection. Results Obvious lesions were observed and fungal examination was positive in untreated, infected pigs on day 8 after infection. In T. mentagrophytes-infecyted pigs, the skin lesion score on day 8, 11, 14 was 9, 1 and 0 in itraconazole group, 8, 5, and 1 in terbinafine group, 48, 52, 40 in untreated group, respectively, and there was significant difference between treated and untreated groups on the three time points (all P<0.01); the mycological cure rates on the above time points were 66.7%, 83.3%, 83.3%, in itraconazole-treated pigs, 83.3%, 83.3%, 83.3%, in terbinafine-treated pigs, 0, 0, 0 in untreated pigs, respectively, with no significant difference between itraconazole and terbinafine group (all P>0.05) but statistical difference between untreated and treated groups (all P<0.01) on all time points. Meanwhile, in M. canis-infected pigs, the skin lesion score on day 8, 11, 14 reached 3, 0, 0 in itraconazole group, 9, 2, 0 in terbinafine group, 46, 47, 39 in untreated group, respectively, and mycological cure rates 83.3%, 83.3%, 83.3% in itraconazole group, 83.3%, 83.3%, 83.3% in terbinafine group, 0, 0, 0 in untreated group, respectively; significant difference was noticed in the two parameters between the treated and untreated groups (all P<0.01) but not between the two treated groups (all P>0.05). Conclusion Itraconazol and terbinafine exhibit similar excellent antifungal activity in routine model of T. mentagrophytes-and M. canis-dermatophytosis.

Dectin-1 mRNA expression in lung of different immune status mice infected with Aspergillus fumigatus / 中华微生物学和免疫学杂志

Objective To study dectin-1 mRNA expression in lung of different immune status mice infected with Aspergillusfumigatus, and to explore the influence of immunosuppressive agent on the expression of dectin-1 and its relationship with the progression of disease. Methods Mice were divided into four groups which were normal control, immuncompromised, immuncompromised with A.fumigatus inoculation and immuncompetent with A.fumigatus inoculation groups. We explored the kinetic mRNA expression of dectin-1 in lung of different groups by real-time quantitative PCR. Pulmonary fungal burden assessment was performed to reflect the progressing of disease during the experimental time course. Results On day 3 after inoculation, pulmonary fungal burden of the immuncompromised mice was higher than that of the immuncompetent group. On day 1 and 3, dectin-I mRNA expression in lung of the immuncompromised group was much lower than that of the normal control. On day 3, dectin-1 mRNA expression in lung of the immuncompetent mice infected with A.fumigatus was much higher than that of the immuncompromised with A.fumigatus inoculation and the normal control groups ( P < 0.05 ). Conclusion During the infection, expression of dectin-1 in lung of the immuncompetent group was strikingly increased, which may play an important role on the defence to A.fumigatus invasion. Cyclophosphamide inhibited the expression of dectin-1 in lung of mice which may be one of the mechanisms of the invasive pulmonary aspergillosis development induced by eyclophosphamide.