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PubMed1994

Analysis of mRNA for class I HLA on human gametogenic cells.

We have studied mRNA expression for Class I HLA (human leukocyte antigen) on male germ cells by amplification of gene fragments in PCR technique and by Northern hybridization. RNA was extracted from fractionated gametogenic cells (isolated from testis) and reversely transcribed. Then, cDNA was amplified for specific HLA sequence (HLA, -A, -B, -C). The specificity of this product was confirmed in "nested" PCR of 400 bp gene fragment coding for alpha 2 domain, alpha 3 domain, and the transmembrane portion of Class I HLA. The results indicate minimal expression of classical Class I HLA on gametogenic cells. Northern hybridization with 669 bp cDNA fragment (spanning for alpha 3 domain, transmembrane, cytoplasmic, and 3' untranslated region) resulted in a low intensity signal from gametogenic cell fractions and confirmed our findings obtained by PCR. The minimal expression of classical HLA antigens may create a neutral cover for the male reproductive system, thereby preventing an immunological response during germ cell differentiation.

Blotting, Northern↗

PubMed1992

Occurrence of distinct PML-RAR-alpha fusion gene isoforms in patients with acute promyelocytic leukemia detected by reverse transcriptase/polymerase chain reaction.

A specific 'nested' reverse transcriptase/polymerase chain reaction (RT/PCR) procedure was used to characterize the expression patterns of PML-RAR-alpha chimeric mRNAs in 32 patients with acute promyelocytic leukemia (APL). The sensitivity of the technique was such that the fusion gene transcript could be detected from as little as 2.5 pg of total leukemic cell RNA against a background of 1 microgram of cellular RNA lacking the PML-RAR-alpha fusion gene transcript(s). In 19 cases the PML-RAR-alpha isoform referred to here as long was identified. A short isoform, which in comparison with the long form lacks three PML exons, was detected in 11 other cases. A third PML-RAR-alpha mRNA isoform, in which the most 3' PML exon present in the long-type isoform was truncated in its sequences lying immediately upstream of RAR-alpha B region, was found and characterized in a single patient. In one APL patient with a variant translocation t(11;17), the PCR product corresponding to PML-RAR-alpha chimeric mRNAs could not be amplified despite the presence of RAR-alpha gene rearrangement. Genomic and PCR analysis showed that the different PML-RAR-alpha isoforms found in APL patients arise as a result of distinct translocation breakpoints. In each case the exons encoding the B-F regions of RAR-alpha are expressed and are spliced downstream from variable PML gene exons. The 'nested' RT/PCR analysis of the PML-RAR-alpha fusion gene proved to be a rapid and sensitive tool for the diagnosis of the APL and for monitoring the residual APL chimeric mRNA expression during complete remission.

Adolescent↗

PubMed2000

[Separation and enrichment of fetal nucleated red blood cells from maternal blood for non-invasive prenatal gene diagnosis].

OBJECTIVE: In order to develop a non-invasive technique for prenatal gene diagnosis. METHODS: Peripheral blood mononuclear cells (MNCs) were separated by single density gradient Histopaque 1.077 from 25 pregnant women with gestations between 8 - 36 weeks. The fetal nucleated red blood cells (NRBCs) were enriched from the MNCs by positive selection using Dynabeads M-450 CD(71) or negative selection using Dynabeads M-450 CD(45). The enriched NRBCs were identified by anti-gamma-biotin or anti-zeta-biotin antibodies. Globin gene of NRBCs from fetuses with risk of beta-thalassemia major were amplified with nested PCR followed by reverse dot blot hybridization for gene diagnosis. RESULTS: NRBCs stained by anti-gamma-biotin or anti-zeta-biotin antibodies could be found in the peripheral blood samples of the 25 pregnant women. Three out of 5 fetuses with risk of beta-thalassemia major were successfully diagnosed using these NRBCs. CONCLUSION: Fetal NRBCs in maternal circulation can be isolated and enriched by single gradient density Histopaque 1.077 followed by magnetic activated cell sorting. Nested PCR can amplify DNA for gene diagnosis from no less than 20 NRBCs.

Biotin↗

PubMed1994

Chromosome locations of human EMX and OTX genes.

We have determined the chromosomal localization of four human homeobox-containing genes, EMX1, EMX2, OTX1, and OTX2, related to Drosophila genes expressed in the developing head of the fly. Murine homologs of these genes are expressed in specific nested domains in the developing rostral brain of midgestation embryos. DNAs from a panel of 19 rodent-human hybrids, each carrying one or a few human chromosomes such that most human chromosome regions were represented, were tested for the presence of the four gene loci by filter hybridization to radiolabeled probes. Regional chromosomal localization was determined by similarly testing DNAs from hybrid mapping panels for each of the candidate chromosomes. Finally, fluorescence in situ hybridization of cosmid clones for these loci refined the locations, two of which were in the vicinity of previously mapped orphan homeobox genes and two of which were near each other. OTX2, the earliest and most widely expressed gene, maps to chromosome region 14q21-q22; the OTX1 locus maps to 2p13; EMX2 maps to 10q26.1; and EMX1, the most narrowly and lately expressed, maps to 2p14-p13. Thus, these homeobox-containing genes involved in brain development are not linked to any of the four HOX clusters on 7p15-p14, 17q21-q22, 12q12-q13, and 2q31. However, the OTX1 and EMX1 loci may be closely linked on or near 2p13, prompting speculation that a clustered gene structure could have functional significance, as is presumably the case for the HOX clusters.

Animals↗

PubMed1995

Use of a semi-nested PCR diagnosis test to evaluate antifolate resistance of Plasmodium falciparum isolates.

The antifols, inhibitors of the dihydrofolate reductase (DHFR), such as pyrimethamine and proguanil, have been used against Plasmodium falciparum in the areas where chloroquine resistance is widespread. This use has selected resistant strains in Southeast Asia and South America. The resistance is correlated with point mutations in precise positions of the DHFR gene. A reliable semi-nested PCR diagnosis test was established and used to determine the genotypic features of 29 isolates of P. falciparum originating from Africa. The results obtained by the PCR technique were compared with those of the in vitro drug sensitivity test. Some isolates were found to be polyclonal. Among the mutations tested, only mutations on codon 108 which generate an asparagine induce a decrease in sensitivity to pyrimethamine and cycloguanil, whereas mutation on codon 59 strengthens resistance to both antifols. No mutation on codon 16 or codon 164 was found.

Animals↗

PubMed1998

[Detection of urogenital malignant cells in the peripheral blood by nested RT-PCR using keratin 19 mRNA].

INTRODUCTION AND OBJECTIVES: It is reported that cytokeratin 19 (CK-19) mRNA is not expressed in the peripheral blood cells of the healthy subjects (Am. J. Pathol. 142: 1111. 1993). Detection of DNA fragments of CK-19 in the peripheral blood suggests the existence of epithelial malignant tumor cells. In this study, we detected CK-19 genes in peripheral blood of patients with urogenital malignancy, and thus clarified the possibility of understanding tumor expansion. METHODS: Mononuclear cells were separated from the peripheral blood of 39 patients with urogenital tumor and 9 controls. Total cellular RNA was extracted according to the method described elsewhere. The CK-19 gene expression was investigated using nested reverse transcription polymerase chain reaction (nested RT-PCR) and confirmed by Southern Blotting. These results were compared to the clinical stages. RESULTS: CK-19 mRNA was not detected in any of 9 controls. CK-19 mRNA was detected in 3 out of the 10 bladder cancer cases. Two had metastases and 1 had muscle invasion without metastasis. One of 6 urothelial cancer case of the upper urinary tract showed positive amplification, and had liver, bone and lymphnode metastases. After one course of chemotherapy, mRNA became negative. In prostate cancer cases, three among 7 were positive and all 3 cases had distant metastases. In renal, testicular and penile cancer cases, the positive ratio were 3/6, 1/8 and 2/2, respectively. All positive cases of renal and testicular cancer had distant metastases, but one case of penile cancer had no metastasis. CONCLUSION: The detection of CK-19 mRNA in the circulating blood by nested RT-PCR makes it possible to detect micrometastasis, to evaluate therapeutic effects and to predict the prognosis.

Adult↗

PubMed2005

[Preliminary exploration of the influence factors on amplification of single cell duplex-nested PCR].

OBJECTIVE: To explore the influence factors on amplification of single cell duplex-nested PCR. METHODS: The mutational loci region CD41-42 and IVS-II 654 of beta-globin gene were amplified by duplex-nested PCR with different combination of primers concentration, different Taq DNA polymerases, different neutralization buffers and with or without predenaturation at 98 degrees C before the PCR amplification in single lymphocyte or single blastomere, thus, to investigate the influence of these factors on the amplification efficiency of PCR. RESULTS: TaKaRa EX Taq was the most efficient Taq DNA polymerase among different Taq DNA polymerases; primer pair R1+F1 at final concentration of 0.25 micromol/L and R2+F2 at 0.3 micromol/L were the most efficient ones in amplification among different combinations of primers concentrations; the amplification efficiency in neutralization buffer-1 (200 mmol/L Tricine) was obviously higher than that of neutralization buffer-2 (900 mmol/L Tris-HCl, pH 8.3/300 mmol/L KCl/200 mmol/L HCl)(P<0.05); there were no remarkable differences of the amplification efficiency while using whether predenaturation at 98 degrees C before the single cell PCR amplification or not (P>0.05). CONCLUSION: There were remarkable differences of the amplification efficiency of single cell duplex-nested PCR while using different combination of primers concentrations, different Taq DNA polymerases, different neutralization buffers. However, predenaturation at 98 degrees C before the single cell PCR amplification could not improve the PCR amplification efficiency.

Humans↗

PubMed2003

Expression of growth hormone and its transcription factor, Pit-1, in early bovine development.

During bovine embryogenesis, bovine growth hormone (bGH) contributes to proliferation, differentiation, and modulation of embryo metabolism. Pituitary-specific transcription factor-1 (Pit-1) is a transcription factor that binds to promoters of GH, prolactin (PRL), and thyroid-stimulating hormone-beta (TSHbeta) encoding genes. A polymorphism in the fifth exon of the bGH gene resulting in a leucine (Leu) to valine (Val) substitution provides an Alu I restriction site when the Leu allele is present. To determine the onset of embryonic expression of the bGH gene, oocytes derived from ovaries homozygous for Leu alleles were fertilized in vitro with spermatozoa obtained from a Val homozygote. For each developmental stage examined, three separate pools of embryos composed of approximately 100 cell samples underwent RNA isolation, reverse transcription to cDNA, and amplification by nested PCR (nPCR). Bovine GH gene transcripts were identified at 2- to 4-cell (n = 162), 8- to 16-cell (n = 73), morulae (n = 51), and blastocyst (n = 15) stages. Likewise, transcripts for Pit-1 were detected at 2-cell (n = 125), 4-cell (n = 114), 8-cell (n = 56), 12-to-32-cell (n = 32), morulae (n = 68), and blastocyst (n = 14) stages. After digestion with Alu1, bGH cDNA was genotyped by restriction fragment length polymorphism (RFLP) analysis. Bovine GH mRNA was present in all pools of stages examined. Both Leu and Val alleles (maternal and paternal) were only detected in pools of embryos that had reached 8- to 16-cell stage. Results suggest that transcription of the bGH gene begins at the 8- to 16-cell stage in bovine embryos, possibly under control of the transcription factor, Pit-1, and that RFLP analysis of the bGH gene can be used to determine parental origin of transcripts in early embryonic development.

Animals↗

PubMed1998

Selective gene transfer into the liver of non-human primates with E1-deleted, E2A-defective, or E1-E4 deleted recombinant adenoviruses.

Preclinical studies were designed to investigate the feasibility and safety of recombinant adenoviruses transduced into the hepatic artery of nonhuman primates. The vectors used are recombinant adenoviruses deleted in E1 and contain either a temperature-sensitive mutation in the E2a gene, which encodes a defective DNA-binding protein at nonpermissive temperatures, or a deletion of the E4 region, including open reading frame (ORF) 6. Six 8- to 10-kg baboons underwent femoral artery cannulation, and angiographic techniques were used to introduce vector selectively into either a portion of the right lobe of the liver via a branch of the right hepatic artery or the common hepatic artery. Necropsies were performed at 4, 29, or 61 days. Serial sequential liver biopsies were performed in the baboons that survived 29 or 61 days. In the 2 baboons with vector transduction into the right hepatic artery, X-Gal histochemical analysis of the liver showed evidence of quantitatively increased gene transfer in the targeted lobe; however, gene transfer was present throughout the liver. Quantitative analysis of histopathology showed that portal inflammation was present throughout both livers transduced with the highest dose of vector. No differences were seen in the level of portal inflammation in targeted and untargeted lobes despite the observed qualitative and quantitative differences in gene expression. Southern blot analysis of total cellular DNA isolated from targeted and nontargeted lobes showed similar levels of viral DNA throughout the liver. Polymerase chain reaction (PCR) analysis was able to detect viral DNA sequence in gonads and brain as well as many other tissues in baboons treated with high-dose vector. In baboons treated with lower doses of an E1-E4 deleted vector expressing the human ornithine transcarbamylase (OTC) gene, DNA was detectable by nested PCR in liver but not gonads at days 29 and 61. The data suggest that intraarterial administration of recombinant adenoviral E1-E4 deleted vector is feasible and safe. At high doses of vector, widespread dissemination of vector DNA is seen. At low doses, hepatic gene transfer is not associated with vector DNA dissemination to gonads.

Adenoviridae↗

PubMed1999

A probable mixed-function supraoperon in Pseudomonas exhibits gene organization features of both intergenomic conservation and gene shuffling.

Sequencing of an 8182-bp chromosomal region in Pseudomonas stutzeri revealed the major portion of an apparent mixed-function supraoperon (defined as a nested organization of transcriptional units encoding gene products which function in more than one biochemical pathway). A nearly identical supraoperon organization was apparent in the unpublished Pseudomonas aeruginosa genome database, where the complete Pseudomonas supraoperon was deduced. The serC(pdxF)-aroQp. pheA-hisHb-tyrAc-aroF-cmk-rpsA supraoperon encodes 3-phosphoserine aminotransferase, a bidomain chorismate mutase/prephenate dehydratase, imidazole acetol-phosphate aminotransferase, cyclohexadienyl dehydrogenase, 5-enolpyruvylshikimate 3-phosphate synthase, cytidylate kinase, and ribosomal protein S1. The member genes were identified by homology analysis, enzyme assay, and/or functional complementation. Although SerC(PdxF) and HisHb exercise their primary functions in serine, pyridoxine, and histidine biosynthesis, they also have critical catalytic roles in provision of the sidechain amino groups of tryptophan, phenylalanine, and tyrosine. The likelihood of supraoperon-wide translational coupling is suggested by the highly compressed intergenic spacing (including overlapping stop and start codons), as well as by possible hairpin structures in mRNA which may sequester some of the ribosome-binding sites and thus provide a mechanism for translational coupling. A comparison of the organization of the supraoperon genes in other organisms represented in the database revealed unmistakable conservation of the linkage of these genes across wide phylogenetic boundaries, albeit with considerable gene shuffling. At least remnants and shuffled portions of the entire supraoperon are distributed throughout the Gram-negative bacteria with the hisHb-tyrA-aroF gene block being conserved as distantly as the gram-positive bacteria. Such conservation of mixed-function genes may reflect the selective value of still-unknown global relationships of protein-protein interaction or regulation.

3-Phosphoshikimate 1-Carboxyvinyltransferase↗

PubMedDate not supplied

Follow-up of minimal residual disease in acute childhood lymphoblastic leukemia by WT1 gene expression in the peripheral blood: the Hungarian experience.

The aim of the study was to investigate if monitoring WT1 gene expression in the peripheral blood is an appropriate approach to monitor the progression of childhood acute lymphoblastic leukemia (ALL). Forty-six patients have been enrolled into this study (24 ALL and 22 control, nonleukemic cases). The peripheral blood was tested for WT1 gene expression using a sensitive nested RT-PCR technique. The assay was sensitive enough to detect 10(2) leukemic cells among 10(6) normal leukocytes. In agreement with the literature 96% of childhood ALL (23/24) expressed WT1 independent of the prognostic factors of the disease. On the other hand, no WT1 gene expression was found in the peripheral blood of nonleukemic hematological diseases, except myelodysplasia. WT1 became negative in the peripheral blood of these patients at the end of the induction phase of the therapy in the majority of the cases (19/24), whereas clinical remission was achieved in all patients except one. WT1 gene expression changes in the peripheral blood was monthly monitored in 20 ALL patients for 1 year and in 16 cases during the second year (for a maximum of 21 months). Although continuous monitoring detected transient (1- to 3-month long) WT1 expression in the majority of the ALL cases (16/20), clinical relapse occurred in 2 cases only when the WT1 expression was maintained for 11-15 months. Follow up studies of the WT1 gene expression in the peripheral blood of WT1-positive childhood ALL may enable researchers to monitor MRD and detect a very low leukemic cell count (perhaps called "molecular relapse"). According to this study, the transient WT1 positivity for 1-3 months does not predict clinical relapse of childhood ALL, unlike a longer-lasting positivity.

Adolescent↗

PubMed2001

Isolation of an intron-containing partial sequence of the gene encoding dermatophyte actin (ACT) and detection of a fragment of the transcript by reverse transcription-nested PCR as a means of assessing the viability of dermatophytes in skin scales.

An internal partial sequence of the gene encoding actin (ACT), 725 to 762 bp in length, was amplified by PCR from the genomic DNA extract of 12 species of dermatophytes and sequenced. An intron that is 56 to 93 bp in length was located along the ACT fragment of all of the dermatophytes at codon position 301 (-3) (a codon number followed by "-3" indicates that the intron directly follows the codon) with reference to the amino acid sequence of human alpha-smooth muscle actin. A primer pair that annealed to exon sequences flanking the ACT-associated intron produced a dermatophyte-specific 171-bp amplicon by reverse transcription-nested PCR (RT-PCR) of dermatophyte ACT mRNA. PCR primer pairs with antisense sequence based on the ACT intron sequence were species specific for dermatophytes, suggesting a potential for use in the identification of dermatophytes. The viability of dermatophytes in skin scales was subsequently assessed by the presence of ACT mRNA in total RNA extracted from a 48-h culture of scale samples in 250 microl of yeast carbon base broth. RT-nested PCR of dermatophyte-infected samples amplified an ACT fragment of the predicted size of 171 bp. The results of viability testing based on ACT mRNA detection by RT-nested PCR correlated with cultural isolation from skin scales. This method is a potential tool for rapidly assessing fungal viability in the therapeutic efficacy testing of antimycotics.

Actins↗

PubMed1999

Phylogenetic differentiation of two closely related Nitrosomonas spp. That inhabit different sediment environments in an oligotrophic freshwater lake.

The population of ammonia-oxidizing bacteria in a temperate oligotrophic freshwater lake was analyzed by recovering 16S ribosomal DNA (rDNA) from lakewater and sediment samples taken throughout a seasonal cycle. Nitrosospira and Nitrosomonas 16S rRNA genes were amplified in a nested PCR, and the identity of the products was confirmed by oligonucleotide hybridization. Nitrosospira DNA was readily identified in all samples, and nitrosomonad DNA of the Nitrosomonas europaea-Nitrosomonas eutropha lineage was also directly detected, but during the summer months only. Phylogenetic delineation with partial (345 bp) 16S rRNA gene sequences of clones obtained from sediments confirmed the fidelity of the amplified nitrosomonad DNA and identified two sequence clusters closely related to either N. europaea or N. eutropha that were equated with the littoral and profundal sediment sites, respectively. Determination of 701-bp sequences for 16S rDNA clones representing each cluster confirmed this delineation. A PCR-restriction fragment length polymorphism (RFLP) system was developed that enabled identification of clones containing N. europaea and N. eutropha 16S rDNA sequences, including subclasses therein. It proved possible to analyze 16S rDNA amplified directly from sediment samples to determine the relative abundance of each species compared with that of the other. N. europaea and N. eutropha are very closely related, and direct evidence for their presence in lake systems is limited. The correlation of each species with a distinct spatial location in sediment is an unusual example of niche adaptation by two genotypically similar bacteria. Their occurrence and relative distribution can now be routinely monitored in relation to environmental variation by the application of PCR-RFLP analysis.

Cloning, Molecular↗

PubMed1993

Rapid detection and identification of mycobacteria in sputum samples by nested polymerase chain reaction and restriction fragment length polymorphisms of dnaJ heat shock protein gene.

In the diagnosis of mycobacterial infection, more than 4-8 weeks is required to identify the species of mycobacterium responsible for an infection. Therefore, the development of a method for the rapid detection and identification of mycobacteria is necessary for selecting an optimal therapeutic plan early in the patient's course. For this purpose, we developed a method combining a nested polymerase chain reaction (nested PCR) procedure and a restriction fragment length polymorphisms (RFLP) analysis of the dnaJ gene of mycobacteria, which codes for a heat shock protein. The PCR procedure allowed the sensitive detection of mycobacterial DNA in clinical samples. Using only 10 femtograms of mycobacterial DNA as a reaction mixture, a detectable band of target DNA segments could be yielded on an agarose gel. This indicates that even with a single genome amount, the PCR is able to detect mycobacteria. The RFLP analysis of the PCR products allowed us rapidly to distinguish the strains belonging to the M.tuberculosis complex from 11 different strains of nontuberculous mycobacteria. Within 2 days, the method is able to identify the mycobacterial species present in the sputum. Moreover, it has the advantage of not requiring the use of radioisotopes, which strongly enhances its clinical usefulness.

Bacteriological Techniques↗

PubMed2000

Promoter activity of the 5' flanking region of the complement receptor type 1 (CR1) gene: basal and induced transcription.

The luciferase reporter gene system was used to assay the basal and Ara-C induced promoter activity of the human CR1 gene in K-562 erythroleukemia cells. Based on the results from clones of nested deletions, both basal and induced reporter gene activity fell to promoterless levels between constructs containing 79 bp (-79) and 41 bp (-41) upstream of the transcription start site. The -79 fragment was shifted in electrophoretic mobility assays using nuclear extracts from Ara-C induced and non-induced cells while the -41 bp fragment was not shifted. These data suggest that the 38 bp region between these constructs is necessary for the transcriptional activity of the CR1 gene and is involved in specifically binding transcription factors from the nuclei of induced and non-induced cells. Several potential transcription factor binding sites in this region were identified.

Base Sequence↗

PubMed2003

A single round PCR method for genotyping human surfactant protein (SP)-A1, SP-A2 and SP-D gene alleles.

The genes coding for the human surfactant proteins (SP)-A and SP-D are located on chromosome 10q22-q23.1. SP-D is the product of a single gene whereas SP-A is the product of two highly homologous genes SP-A1 and SP-A2. Several single nucleotide polymorphisms (SNP) are present in the SP-A1, SP-A2 and SP-D genes. Because of this high degree of sequence homology between the SP-A1 and SP-A2 genes, current genetic analysis studies employ a nested PCR/radioactive hybridization or restriction fragment length polymorphism approach to initially isolate the genes and subsequently to detect the SNP in these isolates. In this manuscript, we report the primers and conditions of a sequence specific primer-PCR methodology that enables the identification of SP-A1, SP-A2 and SP-D gene allelic variants directly on genomic DNA material.

Alleles↗

PubMed1997

Molecular detection and characterization of yellow fever virus in blood and liver specimens of a non-vaccinated fatal human case.

A yellow fever virus of a South American genotype was identified in the liver and blood samples of a non-vaccinated European patient after his return from Brazil. ELISA tests were negative for IgG and positive for IgM against yellow fever. Yellow fever proteins in the formalin-fixed and paraffin-embedded liver biopsy were detected by immunohistochemical procedures. Viral RNA extracted from the liver tissue was also detected using an RT-semi-nested PCR procedure and molecular hybridization. Alignment of the sequence obtained from a gene fragment amplified by RT-semi-nested PCR directly from a blood sample with those of African and South American yellow fever virus strains identified a Brazilian topotype as being responsible for the disease. RT-semi-nested PCR may be used advantageously for clinical specimens for rapid and specific diagnosis, and with archival biopsy material for retrospective studies.

Aedes↗

PubMed2002

Identification of the pathogenic Aspergillus species by nested PCR using a mixture of specific primers to DNA topoisomerase II gene.

For PCR-based identification of Aspergillus species, a common primer of the DNA topoisomerase II genes of Candida, Aspergillus and Penicillium, and species-specific primers of the genomic sequences of DNA topoisomerase II of A. fumigatus, A. niger, A. flavus (A. oryzae), A. nidulans and A. terreus were tested for their specificities in PCR amplifications. The method consisted of amplification of the genomic DNA topoisomerase II gene by a common primer set, followed by a second PCR with a primer mix consisting of 5 species-specific primer pairs for each Aspergillus species. By using the common primer pair, a DNA fragment of approximately 1,200 bp was amplified from the Aspergillus and Penicillium genomic DNAs. Using each species-specific primer pair, unique sizes of PCR products were amplified, all of which corresponded to a species of Aspergillus even in the presence of DNAs of several fungal species. The sensitivity of A. fumigatus to the nested PCR was found to be 100 fg of DNA in the reaction mixture. In the nested PCR obtained by using the primer mix (PsIV), the specific DNA fragment of A. fumigatus was amplified from clinical specimens. These results suggest that this nested PCR method is rapid, simple and available as a tool for identification of pathogenic Aspergillus to a species level.

Aged↗