PCR-RFLP鉴别念珠菌、曲霉和隐球菌的探讨

为快速鉴别３类医学上重要真菌－念珠菌、曲霉和隐球菌,应用聚合酶链反应－限制性片段长度多态（ＰＣＲ－ＲＦＬＰ）的分子生物学说法方法对白念珠菌、克柔念珠菌、季地蒙念珠菌、近平滑珠菌、热带念珠菌、乳念珠菌、新生隐球菌格梯变种、新生隐球菌新生变种、罗伦隐球菌格梯变种、新生隐球菌新生变种、罗伦隐球菌１、工霉、黄曲霉和杂色曲霉进行体外研究。新生隐新生变种、罗伦隐球菌、曲霉隐球菌放增出３１０ｂｐ经ＰＣＲ含珠菌、     

几种隐球菌酶扩增核糖体DNA图谱及快速基因鉴定

DNA的聚合酶链式反应(PCR)和核糖体DNA(rDNA)位点内限制酶切片段长度的多态性分析(RFLP)是遗传学分析的新方法,作者将这两种方法用于隐球菌rDNA的分析.受试菌种含新生隐球菌(19株)、浅白隐球菌(5株)、指甲隐球菌(2株)、罗伦隐球菌(4株)、黑隐球菌(1株)、白念珠菌(2株).将经土豆浸汁培养基中     

墨西哥隐球菌脑膜炎患者中新生隐球菌格特变种的首次报导

近来据文献报导新生隐球菌格特变种(Cryptococcus neoformans var.gattii)可发生在艾滋病患者及非流行区,且与新生隐球菌新型变种(Cryptococcus neoformans var.neoformans)所致隐球菌脑膜炎的临床经过有所不同,因此有必要对隐球菌脑膜炎的病原体的鉴定、分布和临床特点进行研究。作者对此作了研究。 患者来源于墨西哥国立神经病学、神经外科学研究所。1989～1994年共有20例隐球菌脑膜炎患者,隐球菌从患者脑脊液中分离。用二     

新生隐球菌28S rDNA的基因型特征与序列分析

目的 探讨新生隐球菌各变种、血清型与基因型的关系。方法 新生隐球菌标准株10株、新生隐球菌荚膜缺陷株CAP10以及临床分离株19株,采用变性梯度胶电泳(DGGE)结合DNA序列分析,对以上菌株的28S rDNA片段进行研究。结果 经过DGGE和DNA序列分析,所有新生隐球菌新生变种(A、D型)具有一致的基因带型和序列,格特变种(B、C型)具有不同于新生变种的独特一致的带型和序列;AD型的基因型和序列与格特变种完全相同,新生隐球菌荚膜缺陷株CAP10(D型)的基因型类同于新生变种;19株临床分离菌在DGGE上可分为2型,17株与A、D型完全相同,2株与B、C型相同。结论 DGGE结合DNA序列分析,对于探讨新生隐球菌各变种、血清型的基因型特征、关系具有重要价值;我国非艾滋病隐球菌病感染以新生变种为主,AD型在系统发育上更类同于格特变种,而不是新生变种;本研究不支持A血清型为新生变种以外的新变种即grubii变种的观点。     

新生隐球菌AD血清型是新生变种?

新生隐球菌根据传统的分类方法和以往的观点,血清型AD型新生隐球菌一直被视为新生隐球菌新生变种\,但事实上,AD型新生隐球菌无论在地区分布、致病特征等方面,均与新生隐球菌新生变种中的A型和D型有明显不同^[2,3].本文采用变性梯度胶电泳(denaturing gradient gel electrophoresis,DGGE)技术和核酸序列分析,首次发现新生隐球菌AD型28S rDNA基因型与新生隐球菌新生变种的A、D型不同,而与新生隐球菌格特变种B、C型完全一致,现报道如下.     

新型隐球菌变种(S83-1323)引起脑膜脑炎首例报告

1983年我们在上海从1例脑膜脑炎患者脑脊液中分离出一种特异形态的新型隐球菌,其菌体有不同形态47种之多,国内外未见同样报道,经专家鉴定认为本菌为新型隐球菌新的变种.     

新生隐球菌变种问ITS序列差异的研究

目的 利用真菌核糖体基L大1内转录间隔区(ITS)序列分析和系统进化学分析来研究新生隐球菌上海变种的地位及变种问ITS序列的差异.方法 采用真菌通用引物ITS1、ITS4对12株新生隐球菌不同变种标准株的ITS片段进行PCR扩增和测序,结合基因库等数据库中11株新生隐球菌标准株的ITS序列,用CLUSTAL W1.83软件多重比对分析序列的差别,MEGA3.1软件处理数据绘制系统进化树.结果 新生隐球菌变种之间ITS序列存在明显差异,存在6种亚型;gattii变种ITS序列存在4种亚型.中国发现的新生隐球菌上海变种S8012与gattii变种在表型及分子生物学研究均存在显著的差异,但仍属于变种内差异.结论 我国发现的上海变种S8012归入gattii变种的ITSC型,原gattii变种RV20186归人gattii变种的ITSF型.     

腐生性新型隐球菌新型变种的分离

本文报告在扎伊尔的金沙萨市,从室外鸽子与鸡禽的排泄物、室内患有新型隐球菌病合并艾滋病(CN+AIDS)病人与正常人屋子中空气与灰尘中,均分离到了引起隐球菌病的新型隐球菌新型变种。其结果是鸡和鸽子排泄物获得了1.4％和11.3％的阳性率,而5个CN+AIDS患者的屋子和74个其它屋子分别获得了2和3株该菌。虽然新型隐球菌     

见于扎伊尔艾滋病患者的新型隐球菌格蒂变种所引起的脑膜炎

艾滋病诱发隐球菌性脑膜炎者甚多见,主要由新型隐球菌所引起,作者首次报告由新型隐球菌格蒂变种所引起的一例.患者为扎伊尔28岁异性恋男性,铜矿工人,因突发阵发性剧烈头痛二日入院,伴神志模糊、尿沉渣检查有许多红,白细胞,脑脊液检查:淋巴细胞5/mm~3,蛋白55mg//dl,糖67mg/dl,涂片印度墨汁染色找到带荚膜的圆及棒形菌,沙氏葡萄糖琼脂37℃有新型隐球菌生长,经鉴定为格     

新生隐球菌格鲁比变种、新生变种和格特隐球菌的多重聚合酶链反应鉴定

目的 建立一种基于核糖体基因内间隔区（IGS）的多重聚合酶链反应（PCR）,用于快速鉴定新生隐球菌新生变种、格鲁比变种和格特隐球菌。方法 选取新生隐球菌和格特隐球菌IGS中变异度最高的Ⅰ区（IGS1）为靶点,经ClustalW2多重比对,并结合Oligo6软件在不同序列位点设计针对新生隐球菌新生变种、格鲁比变种和格特隐球菌的引物用于多重PCR分析。通过51株新生隐球菌（VNⅠ-VNⅣ和VNB基因型）和41株格特隐球菌（VGⅠ-VGⅣ基因型）对该方法进行验证,并将该方法与已报道的CGB显色培养和采用特异性引物GPA1A、CLA4D和SOD1gattii扩增格鲁比变种、新生变种和格特隐球菌的单一引物PCR方法进行比较。结果 基于IGS的多重PCR分析成功鉴定所有92株新生隐球菌和格特隐球菌,对其他常见致病酵母的扩增均阴性,显示所设计引物较高的特异性;已报道的基于GPA1A和CLA4D引物PCR分别在鉴定2株和1株格特隐球菌时出现假阳性结果;CGB培养基在鉴定1株格鲁比变种和1株新生变种时出现假阳性结果。上述方法在鉴定时均未出现假阴性结果。结论 建立的多重PCR可快速准确地鉴定新生隐球菌新生变种、格鲁比变种、AD杂合子和格特隐球菌,且优于已报道的单一引物PCR 或CGB显色培养法。     

Analysis of the 3'UTR of the prostaglandin synthetase-2 (PTGS-2/COX-2) gene in non-melanoma skin cancer after organ transplantation

To define the potential involvement of polymorphisms in the 3'untranslated region (3'UTR) of the prostaglandin synthetase-2 (PTGS-2) gene to non-melanoma skin cancer (NMSC) predisposition after transplantation, we screened for genetic variant, relevant parts of this region. It contains binding sites for trans-acting factors, an alternative polyadenylation site and putative target sequences for miRNAs. Variant +8473T>C did not appear to play a functional role in the regulation of gene expression in human keratinocyte-transfected cells. In addition to the well-known +8473T>C, we identified four polymorphisms: +8293G>C, +10259T>G, +10267G>A and +10335G>A. No allele frequency differences were observed between cases and controls neither for +8473T>C nor for any of the identified polymorphisms, suggesting that polymorphisms in the 3'UTR of the PTGS2 gene are rare and unlikely to represent risk factor for NMSC after transplantation.     

Genotype-phenotype correlation in Chinese patients with dystrophic epidermolysis bullosa pruriginosa

Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) is a rare variant of dystrophic epidermolysis bullosa (DEB) due to dominant or recessive mutations in the COL7A1 gene. More than 40 mutations in COL7A1 have been described in DEB-Pr. The aim of this study was to understand the genotype-phenotype correlation in Chinese patients with DEB-Pr. Three Chinese families with typical clinical features of DEB-Pr were studied. The results were analysed in association with the eight Chinese DEB-Pr patients reported in the literature. In the three Chinese families with DEB-Pr, we found two dominant cases with G1773R and c.6900+1G>C mutations, and one case with heterozygous G2701W mutation of uncertain inheritance mode. In the 10 Chinese patients with dominant type of DEB-Pr, 7 glycine substitutions and three splicing site mutations of exon 87 skipping were identified. Glycine substitution mutations in the triple helix region and exon 87 skipping, leading to the in-frame deletion of 23 amino acid residues in the triple-helix, are often seen in Chinese patients with dominant DEB-Pr, although the glycine substitutions are also frequently present in dominant DEB.     

宫颈癌标本中HPV16的E6、E7和LCR的变异研究

目的:探究分析E6、E7和LCR(long control region,LCR)在宫颈癌标本中HPV16中的变异情况。方法:随机选取我院病理实验室于2015年1月至2016年1月期间留存的HPV16阳性宫颈癌标本100例为研究对象,分别采用PCR技术进行E6、E7和LCR片段的扩增处理,并采用DNA序列进行PCR扩增产物的序列测定,分析E6、E7和LCR的变异表现。结果:E6基因中最常见变异为T350G(67.27%),E7基因中最常见变异为T789C(72.67%),LCR最常见变异为G7521A(90.90%),LCR区中出现G7799A、A7636C、C13T、C7678T新变异,E7区高度保守,YY1转录因子结合点是LCR变异的主要集中点。结论:宫颈癌标本中HPV16存在E6、E7和LCR变异情况,分析高危型HPV变异有助于宫颈癌HPV的早期诊断,可将其应用于宫颈癌防治的疫苗设计中,具有广泛的临床应用前景。     

念珠菌属七个菌种的DNA G+C(%)含量测定

作者等通过对临床常见7种念珠菌的DNAG+C(%)测定,发现这些菌的G+C(%)变化范围在30.74-45.24之间,各菌之间相差不等,克柔氏念珠菌,副克柔氏念珠菌和伪热带念珠菌的G+C(%)值无明显差别,高里氏念珠菌的值最高.这些菌的DNA G+C(%)的测定目前虽不能完全作为菌种的鉴别特性,但可为菌种的鉴定提供遗传学基础.因为它们不受环境等生长条件的影响,可作为一种鉴定菌种的参考指标.     

Association of functional gene variants in the regulatory regions of COX-2 gene (PTGS2) with nonmelanoma skin cancer after organ transplantation

BACKGROUND: Overexpression of cyclooxygenase-2 (COX-2), resulting in excessive prostaglandin production, has been observed in human epidermal keratinocytes after ultraviolet B injury, in squamous cell skin carcinoma (SCC), in actinic keratoses, and in the early stages of carcinogenesis in a wide variety of tissues. The dysregulation of COX-2 expression can in part be due to functional changes affecting regulatory elements in the promoter or 3' untranslated region (UTR) of the gene. Two common polymorphisms (-765G-->C, and -1195A-->G) in the promoter region of the COX-2 gene (now PTGS2), and one common polymorphism in the 3' UTR (8473T-->C) have been described, and reported as associated with various malignancies. OBJECTIVES: To determine if common known polymorphisms in the regulatory region of the COX-2 gene (PTGS2) can be associated with nonmelanoma skin cancer (NMSC) predisposition after organ transplantation, to evaluate if cancer risks are associated with specific COX-2 gene (PTGS2) haplotypes containing these polymorphisms, and to identify possible new genetic polymorphisms in the proximal 5' or 3' regulatory regions of the gene associated with disease. METHODS: The frequency of the three polymorphisms was determined in 240 Northern Italian transplant recipient patients (107 cases and 133 controls) with polymerase chain reaction-restriction fragment length polymorphism analysis. The proximal 5' and 3' regulatory regions of the gene were screened by heteroduplex analysis. RESULTS: Stratification by age at transplant and type of tumours [SCC or basal cell carcinoma (BCC)] demonstrated that allele -765C represented a protective factor in BCC cases undergoing transplantation before 50 years of age (CC + CG vs. GG, Fisher exact test P = 0.003). One rare polymorphism, -62C-->G, was detected in the 5' flanking region. The allele frequency of -62G was 0.019, and no difference in genotype between cases and controls was observed. No other variants were found, suggesting that sequence variations in these regions are not likely to contribute to NMSC risk in this population. Haplotype analysis showed that the haplotype containing all major alleles represents a protective factor in patients with SCC undergoing transplantation after 50 years of age [P = 0.009; OR = 0.37 (0.18-0.79)] and that variant -1195A-->G may represent a risk factor in this subgroup of patients [P = 0.01; OR = 4.77 (1.47-16.41)]. Haplotype analysis in patients with BCC revealed that variant -765C might be a protective factor in patients undergoing transplantation before 50 years of age. Variant 8473T-->C, located in the 3' UTR region of the gene, showed no association with NMSC risk after transplantation. CONCLUSIONS: COX-2 common variants -765G-->C and -1195A-->G appear to be associated with risk of NMSC, although in different ways in the SCC and BCC subgroups, indicating that environmental and genetic risk factors may play different roles in the outcome leading to these two phenotypes.     

Xeroderma pigmentosum variant associated with multiple cancers

A 62-year-old Japanese man with xeroderma pigmentosum (XP) variant is reported. The patient had developed at least 6 basal cell carcinomas, a squamous cell carcinoma, and a malignant melanoma on sun-exposed areas, and an atypical carcinoid on the right lung. In vivo phototesting showed a normal response. The minimal erythema dose of ultraviolet B (UVB) was not lowered and no delayed peaking of the erythema reaction was observed. His skin fibroblasts exhibited higher sensitivity to UV irradiation, but a normal level of unscheduled DNA and RNA synthesis. Cell fusions with XP group A, C, D, E, F, and G cells after UV irradiation were all complemented. Previous reports together with this case suggest that older XP variant patients have a high frequency of not only skin cancers, but also internal malignancies.     

CD30+ lymphoproliferative disorder with spindle‐cell morphology

Lymphomatoid papulosis (LyP) is classified as a CD30+ primary cutaneous lymphoproliferative disease. The phenotypic variability along the spectrum of CD30+ lymphoproliferative diseases is highlighted by the distinct histologic subtypes of LyP types A, B, C, and the more recently described types D, E, and F. We report the case of an elderly woman with a clinical presentation and histopathologic findings consistent with LyP, whose atypical CD30+ infiltrate uniquely demonstrated a spindle‐cell morphology. To our knowledge, this is the first reported case of LyP characterized by CD30+ spindle‐shaped cells, and may represent a new and distinct histologic variant of LyP.     

Functional associations of genetic variants involved in the clinical manifestation of erythropoietic protoporphyria in the Argentinean population

Background Combined inheritance of genetic variants in ferrochelatase gene (FECH) are implicated in clinical manifestation of Erythropoietic Protoporphyria (EPP). Objective Identify the genetic variants in FECH gene and their associations in the expression of EPP in Argentina. Determine the allelic frequency of polymorphic variants, associations in cis and its linkage disequilibrium. Methods The FECH gene was PCR‐amplified and sequenced. Allelic variants of intragenic polymorphisms were identified by PCR followed by sequencing or restriction digestion analysis. Residual FECH activity was determined by prokaryotic expression in Escherichia coli JM109. Data were analyzed using Haploview and Statistix 9. Results Ten mutations were identified: three novel (p.S222N; p.R298X and p.R367X) and seven already known (g.12490_18067del; p.R115X; p.I186T; c.580_584delTACAG; c.598 + 1 G>T; p.Y209X and p.W310X). The p.R115X mutation was found in two families. The p.S222N mutation expressed 5% of normal activity. Only individuals who inherited a mutation combined in trans to a low expression allele c.1‐251G, c.68‐23T, and c.315‐48C, showed clinical symptoms. The absence of c.315‐48C variant was sufficient for not triggering EPP. However, these variants showed high levels of cosegregation and GTC haplotype is over‐represented in EPP patients. Conclusion In the dominant inheritance form of EPP, c.315‐48C variant in trans to the mutated allele is sufficient to trigger the disease. The presence of GTC haplotype in all patients with dominant EPP could be due to the high level of cosegregation of c.315‐48C with c.1‐251G and c.68‐23T variants in our population.     

UV fingerprints predominate in the PTCH mutation spectra of basal cell carcinomas independent of clinical phenotype

Basal cell carcinoma (BCC) shows a wide interpatient variation in lesion accrual. To determine whether certain tumorigenic fingerprints and potentially predisposing patched (PTCH) tumor suppressor single-nucleotide polymorphisms (SNPs) are distributed differently among sporadic BCC patients, we compared the PTCH mutation spectra in early-onset BCC (first lesion at age < 35 years), regular BCC (first lesion at age > or = 35 years and < 10 lesions), and multiple BCC (> or = 10 lesions). The PTCH gene was mutated in 29 of 60 cases (48%). Most of the PTCH mutations bore the UV fingerprint (i.e., C --> T or tandem CC --> TT transitions at dipyrimidine sites). However, neither the proportion nor the spectra of exonic PTCH mutations differed significantly among the three groups. A large number of SNPs (IVS10+99C/T, IVS11-51G/C, 1665T/C, 1686C/T, IVS15+9G/C, IVS16-80G/C, IVS17+21G/A, and 3944C/T or its combinations) were also detected, but again their incidence did not differ significantly among the groups. Interestingly, expression of the IVS16-80G/C and the IVS17+21G/A genotype did not achieve the Hardy-Weinberg equilibrium in patients with regular and/or early-onset BCC. These data suggest that a (UV-) mutated PTCH gene is important for sporadic BCC formation independent of clinical phenotype and that the IVS16-80G/C and/or IVS17+21G/A SNP site might be important for tumorigenesis in certain BCC patients.