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Results for “Nested Genes”

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PubMed2003

[Sequence variation in the env V3-V4 region of HIV type 1 predominant subtype B and C strains circulating in China].

OBJECTIVE: To identify genetic variation of HIV-1 predominant subtype B and C strains in China during rapid horizontal transmission and to elucidate the potential relationship between genetic variation and selective pressure. METHODS: After the fragments of HIV-1 env gene were amplified by nested-PCR from the whole blood of 258 HIV-1 infected individuals, PCR products were directly sequenced using ABI 377 DNA sequencer. The sequences covering env V3-V4 region of 72 HIV-1 subtype B(n=37) and C(n=35) strains were selected for phylogenetic analysis. In addition, the ratios of synonymous (Ks) substitutions per nonsynonymous (Ka) substitutions were calculated using DIVERGE. RESULTS: The genetic distances of the V3-V4 region of subtype B strains were higher than that of subtype C strains. Furthermore, sequence analysis revealed that the V4 region was more variable than the V3 region for both subtype B and C strains. What's more, the V3 loop was less variable compared with the V3 upstream region and C3 region for subtype C Ks/Ka ratios of the entire aligned sequence of the two subtypes were below 1 0, with the lowest values found in the V3 region of subtype B strain and the V4 region of subtype C strain. CONCLUSIONS: The majority of variation in both subtypes B and C strains occurred in the V4 rather than the V3 region. It is important that our study found for the first time the V3 loop was more conservative than the V3 upstream region and C3 region for subtype C. Calculations of the Ks/Ka ratios throughout the V3-V4 region demonstrate that significant selective pressures experienced during the rapid horizontal spread of the virus in the Chinese HIV-1 infected population may have directed change in the V3 loop for the subtype B strain and the V4 loop for the subtype C strain. These results will contribute to the policy of AIDS prevention and control and the ongoing development vaccine.

Amino Acid Sequence↗

PubMed1999

Comparative sequence analyses of sixteen reptilian paramyxoviruses.

Viral genomic RNA of Fer-de-Lance virus (FDLV), a paramyxovirus highly pathogenic for reptiles, was reverse transcribed and cloned. Plasmids with significant sequence similarities to the hemagglutinin-neuraminidase (HN) and polymerase (L) genes of mammalian paramyxoviruses were identified by BLAST search. Partial sequences of the FDLV genes were used to design primers for amplification by nested polymerase chain reaction (PCR) and sequencing of 518-bp L gene and 352-bp HN gene fragments from a collection of 15 previously uncharacterized reptilian paramyxoviruses. Phylogenetic analyses of the partial L and HN sequences produced similar trees in which there were two distinct subgroups of isolates that were supported with maximum bootstrap values, and several intermediate isolates. Within each subgroup the nucleotide divergence values were less than 2.5%, while the divergence between the two subgroups was 20-22%. This indicated that the two subgroups represent distinct virus species containing multiple virus strains. The five intermediate isolates had nucleotide divergence values of 11-20% and may represent additional distinct species. In addition to establishing diversity among reptilian paramyxoviruses, the phylogenetic groupings showed some correlation with geographic location, and clearly demonstrated a low level of host species-specificity within these viruses.

Animals↗

PubMed2005

[Identification of signature amino acids in the env V3-V4 and flanking regions of human immunodeficiency virus type 1 predominant strains in China].

OBJECTIVE: To identify signature amino acids in the V3-V4 and flanking regions of the env gene from human immunodeficiency virus type 1 (HIV-1) predominant strains in China and to elucidate the role of these signature amino acids on epidemiologic tracking and the development of vaccine. METHODS: Fragments of the HIV-1 env gene were amplified by nested-PCR from the whole blood of HIV-1 infected individuals from 12 provinces in China. Then, the PCR products were directly sequenced by using ABI 377 DNA SEQUENCER. The sequences covering the env V3-V4 region of the strains were used for the analyses described here. Envelope sequence subtypes were assigned using BLAST (http://www.HIV-Web.lanl.gov). Phylogenetic analyses were performed using GCG and MEGA as well as signature amino acids were identified using VESPA. RESULTS: Subtype B' strains and two recombinants (B'/C and CRF01-AE) were discovered among 157 currently circulating strains in China. The most prevalent subtypes were B'/C (38.85%), followed by B' (34.40%), and CRF01-AE (26.75%). Phylogenetic tree analysis of env V3-V4 region showed that subtype B' strains were closely related to B.CN.RL42, while most of B'/C strains clustered with 97CN54A and 97CNGX6F, CRF01-AE strains clustered into two distinct subgroups, which were closely related to THCM240 and 97CNGX2F. Analysis of signature amino acids revealed that eight of positions were identified as conserved signature amino acid sites in the env V3-V4 and flanking regions of the subtype B' and B'/C strains and almost all signature amino acids were found in their reference strains. Interestingly, eleven signature amino acids were demonstrated in the same regions of the CRF01-AE strains, but nine out of 11 signature amino acid sites were distinct from the same positions of the reference strains 97CNGX2F and TH.CM240. It is noteworthy that these 9 signature amino acids were found in the strains from all of the selected provinces except those from Yunnan province. CONCLUSION: Analysis of the signature amino acids suggest that much of the current Chinese epidemics of subtype B' and B'/C strains are descended from a single introduction into China, while the epidemic caused by the CRF01-AE strain is caused by multiple introductions into China from Thailand. These results will contribute to the policy of AIDS prevention and control as well as the ongoing development of AIDS vaccine.

Adolescent↗

PubMed2003

[Study on the evolutionary pressure on the env gene of the human immunodeficiency virus type 1 CRF01-AE strains circulating in China].

OBJECTIVE: To identify variations in the env gene of human immunodeficiency virus type 1 (HIV-1) subtype CRF01-AE strains circulating in China and to elucidate the potential relationship between genetic variation and evolutionary pressure. METHODS: Fragments of the HIV-1 env gene were amplified by nested-polymerase chain reaction (n-PCR) from the whole blood of HIV-1 infected individuals from four provinces in Southeast China (Guangdong, Hunan, Jiangsu and Jiangxi). The PCR products were then directly sequenced by ABI 377 DNA sequencers. The sequences covering the env V3-V4 region of 34 HIV-1 subtype CRF01-AE strains were selected to analyse phylogenetic trees and amino acid mutations. The accumulation of synonymous (Ks) and antonymous (Ka) substitutions as well as Ks/Ka ratios were calculated using DIVERGE. RESULTS: Phylogenetic trees showed that the 34 HIV-1 subtype CRF01-AE strains from China clustered with the Chinese AE reference strain (AE.97CNGX2F), as well as with the reference strains from Thailand (AE.CM240 and AE.93TH253). The amino acid sequences of the env V4 and C3 regions in the samples were highly variable, compared with those of V3 and V3-downstream regions. The V3 loop central motif in the majority (87.5%) of the strains was GPGQ. The majority of strains did not contain positively charged amino acids at positions 306 and 320 in V3 loop. The N-linked glycosylation sites in the V3-V4 region and flanking regions in these strains were relatively conserved. Analysis of the entire region showed that the mean Ks values were significantly higher than that of the Ka values (P < 0.001), with the Ks/Ka significantly higher than 1.0 (P < 0.001). In contrast, the Ks/Ka ratio in the V4 region was significantly lower than 1.0 (P < 0.01). CONCLUSIONS: Our study indicated that the majority of HIV-1 subtype CRF01-AE strains circulating in China were highly homogeneous. The amino acid sequences of the V4 and C3 regions were significantly more variable than those of the V3 loop. Our analysis also suggested that the phenotype of nearly all strains was likely to be non-syncytium inducing (NSI). Finally, the variation found in the V3-V4 sequence was significantly influenced by functional constraints as opposed to positive selective pressure, while the variability of the lone V4 region was strongly related to positive selective pressure.

Adult↗

PubMed2007

Isolation and gene quantification of heterotrophic N2-fixing bacterioplankton in the Baltic Sea.

Cyanobacteria are regarded as the main N(2)-fixing organisms in marine waters. However, recent clone libraries from various oceans show a wide distribution of the dinitrogenase reductase gene (nifH) originating from heterotrophic bacterioplankton. We isolated heterotrophic N(2)-fixing bacteria from Baltic Sea bacterioplankton using low-nitrogen plates and semi-solid diazotroph medium (SSDM) tubes. Isolates were analysed for the nitrogenase (nifH) gene and active N(2) fixation by nested polymerase chain reaction (PCR) and acetylene reduction respectively. A primer-probe set targeting the nifH gene from a gamma-proteobacterial isolate, 97% 16S rDNA similarity to Pseudomonas stutzeri, was designed for measuring in situ dynamics using quantitative real-time PCR. This nifH gene sequence was detected at two of 11 stations in a Baltic Proper transect at abundances of 3 x 10(4) and 0.8 x 10(3) copies per litre seawater respectively. Oxygen requirements of isolates were examined by cultivation in SSDM tubes where oxygen gradients were determined with microelectrodes. Growth, and thereby N(2) fixation, was observed as horizontal bands formed at oxygen levels of 0-6% air saturation. The apparent microaerophilic or facultative anaerobic nature of the isolates explains why the SSDM approach is the most appropriate isolation method. Our study illustrates how combined isolation, functional analyses and in situ quantification yielded insights into the oxygen requirements of heterotrophic N(2)-fixing bacterioplankton isolates, which were confirmed to be present in situ.

Bacteria↗

PubMed2003

[Identification and molecular cloning and sequence analysis of a novel coronavirus from patients with SARS by RT-PCR].

OBJECTIVE: To investigate the etiologic agents of the SARS and develop diagnostic method for this disease. METHODS: Thirty-six nasopharyngeal aspirate specimens from 27 patients with SARS in Shenzhen were collected. The samples were aliquotted to three parts and subjected to molecular assays for human metapneumovirus, chlamydia and a novel coronavirus, which was reported recently to be the etiologic agent of SARS. Nested RT-PCR was used to amplify the RNA polymerase gene of the novel coronavirus and the PCR products were sequenced directly or after cloned to pMD18-T vector. RESULTS: Human metapneumovirus and chlamydia genes were detected in none of the specimens using the RT-PCR and nested-PCR, respectively. The novel coronavirus gene were amplified in 6 of 36 specimens, the sequence analysis indicated that this novel coronavirus is unrelated to any other coronavirus reported previously. The nucleotide and deduced amino acid alignment between this coronavirus and others was not more than 40% and 70% to 82%, respectively, while the nucleotide sequence cloned from the 6 patients were identical. CONCLUSIONS: The SARS patients in Shenzhen were infected with coronavirus and this novel coronavirus is associated with SARS. The sequence analysis indicated that the coronavirus from SARS patients in Shenzhen is the same as that identified from other areas such as Canada and Hong Kong. A specific diagnostic nested RT-PCR was developed to identify this novel coronavirus infection.

Adolescent↗

PubMed2002

Fluorescent polymerase chain reaction and capillary electrophoresis for IgH rearrangement and minimal residual disease evaluation in multiple myeloma.

BACKGROUND AND OBJECTIVES: Several polymerase chain reaction (PCR)-based techniques for tracking minimal residual disease (MRD) in B-lymphoproliferative disorders have been recently proposed. These procedures show significant variation in sensitivity and specificity. We describe an alternative assay based on fluorescent PCR combined with capillary electrophoresis and GeneScan analysis, to identify the monoclonal immunoglobulin heavy chain (IgH) rearrangement in multiple myeloma (MM) and to provide a semi-quantitative evaluation of MRD by limiting dilutions. DESIGN AND METHODS: Different sets of family specific primers derived from the leader region and from the framework-1 of IgH were used, with a unique reverse fluorescent primer JH. The malignant clone was identified by GeneScan and sequenced. Two tumor primers, mapping in the complementarity determining regions CDRII and CDRIII, were designed for each patient. A comparison between the nested-PCR approach and direct fluorescent PCR was performed for three patients in complete clinical remission after autologous or allogeneic bone marrow transplantation. RESULTS: Thirty-six consecutive patients with MM were screened and monoclonality was identified in about 70% of the cases. Molecular MRD evaluation was performed in 18 patients using tumor primers. This method allowed identification of 1 neoplastic cell among 10(4)-10(6) normal cells. In three cases, negative by nested-PCR and agarose gel electrophoresis, gene scanning showed persistence of the neoplastic clone, despite the negativity of the immunofixation. INTERPRETATION AND CONCLUSIONS: Capillary electrophoresis of fluorescent fragments with gene scanning provides a simple, rapid and reproducible method to detect IgH rearrangement and to evaluate MRD. Furthermore, the sensitivity reached is up to 1 log higher than that of the conventional approach with nested-PCR, even though two steps of specificity are maintained.

Adult↗

PubMed2004

Preimplantation genetic diagnosis for Niemann-Pick disease type B.

BACKGROUND: Acid sphingomyelinase (ASM) deficient Niemann-Pick disease (NPD) is an autosomal recessive disorder caused by mutations in the ASM gene (SMPD1). More than 70 different mutations have been reported in this gene. NPD type B is the most common type in Saudi Arabia with a frequency of 1:40 000 to 1:100 000. The phenotype of Saudi Type B patients is more severe than patients reported from the West. Two mutations specific to Saudi patients have been inherited in the SMPD1 gene. Given the difficult management of the disease, we opted for a preventive approach to the suffering families by screening the whole SMPD1 gene for mutations followed by Preimplantation Genetic Diagnosis (PGD). METHODS: The family suffering from NPD-B underwent mutation screening for the entire SMPD1 gene followed by PGD using nested PCR and sequencing. RESULTS: A novel mutation in a family suffering from the same severe NPD-B phenotype is described in this report (W533R). After PGD, a singleton pregnancy ensued after transfer of one heterozygous and one normal embryo. Postnatal DNA testing of the newborn showed a normal homozygous genotype. CONCLUSIONS: This report reveals a new SMPD1 mutation responsible for similar Saudi severe phenotype, and the prevention of this disorder by PGD.

Adult↗

PubMed1994

The role of molecular genetics in speciation studies.

Systematists and population geneticists can both use molecular data sets to construct evolutionary trees (species and gene trees, respectively), and then use the resulting historical framework to test a variety of hypotheses. The greatest prospect for future advances in our understanding of speciation is to extend these historical approaches to the species/population interface, for only by straddling this interface can we actually study the processes involved in the origin of a new species. This chapter illustrates how the bottom-up historical approaches used in population genetics can be extended upwards to this critical interface in order to separate the effects of population structure from population history, to rigorously test the species status of a group, and to test hypotheses about the process of speciation by using gene trees to define a nested, statistical analysis of biogeographic and other types of data.

Animals↗

PubMed2005

Toxoplasmosis surveillance during pregnancy and quality assurance of methods in Hungary.

In Hungary, screening programs have been performed for the early detection of toxoplasmosis in pregnant women in three different counties. The results of a screening program performed in the town of Szeged are discussed in details. The pregnant women are screened by serological and molecular biological methods (anti-Toxoplasma CFT, IgG, IgM, anti-P30 IgA ELISA, IgG avidity test, PCR amplification). The women are first screened within the first 16 weeks of gestation. Seronegative cases are retested for seroconversion in every second month. Appropriate treatment is immediately started both in the mothers suspicious of acute toxoplasmosis and in their offspring. The urine samples of the babies are examined by nested PCR specific to B1 gene of Toxoplasma gondii. No cases of congenital toxoplasmosis have been detected among the screened and treated children so far. Thus, we consider the program as highly successful for screening of congenital toxoplasmosis. To insure the quality of the applied laboratory diagnostic methods, the QualiCont Company organizes two quality control investigations yearly in the laboratories involved.

Female↗

PubMed2005

Nucleotide sequence of a new isolate of ribgrass mosaic tobamovirus infecting Impatiens New Guinea.

The complete nucleotide sequence of a tobamovirus isolated from Impatiens New Guinea was determined. The genome was 6302 nt long, and its genomic organisation was similar to those of other crucufer tobamoviruses. Sequence comparisons with the corresponding sequences of other crucifer tobamoviruses revealed highest levels of identity with the ribgrass mosaic virus (Shanghai isolate). A small open reading frame putatively encoding a 4.5-kDa protein with a low degree of similarity to the ORF6 of tobacco mosaic virus was found nested in the movement protein gene.

Amino Acid Sequence↗

PubMed1995

CMV PCR monitoring in leucocytes of transplant patients.

BACKGROUND: The presumed latency of cytomegalovirus (CMV) in leucocytes and the sensitivity of the polymerase chain reaction (PCR) raise a question of its clinical value. OBJECTIVES: To develop and standardize a CMV PCR as a diagnostic tool for CMV infection in solid organ and bone marrow transplant patients by comparing it to a likewise standardized isolation, rapid isolation and to clinical symptoms. STUDY DESIGN: The material comprised 822 EDTA peripheral blood samples from 96 solid organ and 119 bone marrow transplant patients. One sample from each of 21 healthy bone marrow donors and 25 blood donors were used as controls. Two million leucocytes were lysed and one-tenth of a volume was used in a nested PCR employing immediate early gene primers. RESULTS: The limit of detection was approximately 10 gene copies of a CMV DNA clone and 1 TCID(50) of extracted DNA from a cell suspension. The specificity was >/=0.99 when tested in CMV seronegative individuals. The positive and negative predictive values were 0.62 and 1.00, respectively. When PCR was compared to virus isolation/rapid culture in individual patients, PCR was positive more frequently in solid organ transplant patients than was CMV isolation/rapid culture, but the difference was not significant in bone marrow transplant patients. In isolation-positive patients, PCR became positive in samples taken 1-2 weeks earlier. In 54 solid organ transplant patients with PCR-positive samples, CMV-associated symptoms were present in 29/31 patients with CMV isolated from blood but in only 5/23 patients without viraemia. In 17 bone marrow transplant patients treated with ganciclovir, PCR became negative during or immediately after treatment in 14/20 (70%) episodes. This was true of 5/12 (42%) solid organ transplant patients. CONCLUSION: Screening of transplant patients with CMV PCR can be standardized at a clinically relevant level so that antiviral therapy can be instituted early.

Journal Article↗

PubMed2006

Dechlorination after thermal treatment of a TCE-contaminated aquifer: laboratory experiments.

A microcosm study was conducted to evaluate dechlorination of trichloroethene (TCE) to ethene and survival of dechlorinating bacteria after a thermal treatment in order to explore the potential for post-thermal bioremediation. Unamended microcosms containing groundwater and aquifer material from a contaminated site dechlorinated TCE to cis-1,2-dichloroethene (cDCE), while lactate-amended microcosms dechlorinated TCE to cDCE or ethene. A thermal treatment was simulated by heating a sub-set of microcosms to 100 degrees C for 10d followed by cooling to 10 degrees C over 150 d. The heated microcosms demonstrated no dechlorination when unamended. However, when amended with lactate, cDCE was produced in 2 out of 6 microcosms within 300 d after heating. Dechlorination of TCE to cDCE thus occurred in fewer heated (2 out of 12) than unheated (10 out of 12) microcosms. In unheated microcosms, the presence of dechlorinating microorganisms, including Dehalococcoides, was confirmed using nested PCR of 16S rRNA genes. Dechlorinating microorganisms were detected in fewer microcosms after heating, and Dehalococcoides were not detected in any microcosms after heating. Dechlorination may therefore be limited after a thermal treatment in areas that have been heated to 100 degrees C. Thus, inflow of groundwater containing dechlorinating microorganisms and/or bioaugmention may be needed for anaerobic dechlorination to occur after a thermal treatment.

Bacteria↗

PubMed2006

The emergence of cytomegalovirus resistance to ganciclovir therapy in kidney transplant recipients.

Transplant recipients that have not been previously exposed to the cytomegalovirus (CMV) are highly susceptible to viral diseases while under immunosuppression therapy. CMV disease requires prolonged therapy, facilitating the emergence of resistant strains. Persistence of positive antigenemia represents clinical evidence of the presence of resistant strains, although its frequency is unknown. These strains may present amino acid deletions or substitutions in conserved regions of the UL97 protein, point mutations in the DNA polymerase (UL54), or both. In this study we aimed to analyze the prevalence of mutations associated with ganciclovir resistance in transplant recipients. Fifteen kidney transplant recipients and four kidney-pancreas transplant recipients, with a positive and oscillating CMV viremia detected by sequential antigenemia test, were enrolled. The UL97 gene was amplified by Nested-PCR and enzymatically digested in samples of these patients in order to detect mutations in the most common codons, such as 460 (M460V), 594 (A594V) and 595(L595S/F). The end-product fragments were further sequenced. Nine (47.4%) out of 19 patients presented with mutations in UL97 at codons L595S (55.6%), A594V (11.1%), A595F/A594V (11.1%) and L595S/A594V (22.2%). None presented with mutation at the M460V codon. Renal transplant patients with oscillation in viral load for more than 2 weeks might have developed viral resistance to anti-drug therapy. Its detection might aid physicians in their clinical plan of tapering the patient's immunosuppression.

Adolescent↗

PubMed2006

Distribution and heterogeneity of small ruminant lentivirus envelope subtypes in naturally infected French sheep.

Small ruminants lentiviruses (SRLV) nucleotide sequences spanning the V1V2 variable regions of the env gene were amplified by nested-PCR from 38 blood samples collected from 16 naturally infected sheep flocks in France. For the rapid SRLV group determination of field isolates, the PCR-amplified fragments were subjected to a SRLV-adapted heteroduplex mobility assay (HMA). All viral sequences were clearly assignable to the SRLV group B by HMA analysis. Twenty-seven SRLV isolates were selected for DNA sequence analysis. In each case, nucleotide comparison and phylogenetic analyses confirmed the genetic relationships inferred by HMA. Six SRLV isolates belonged to subtype B1, and 21 pertained to subtype B2, one flock being infected with both subtypes. Subtypes B1 and B2 were found with different frequencies and geographic spread, but exhibited similar genetic diversities. These results give a more complete picture of the distribution and heterogeneity of SRLV env subtypes in sheep and confirmed that multiple interspecies transmission occurred in the past. Furthermore, HMA appeared to be a rapid and reliable method to differentiate caprine arthritis encephalitis virus from maedi-visna virus.

Animals↗

PubMed2003

Detection of Chlamydia suis from clinical specimens: comparison of PCR, antigen ELISA, and culture.

Cell culture is still widely regarded as the gold standard in chlamydial diagnosis despite its well-known limitations in terms of sensitivity. On the other hand, the polymerase chain reaction (PCR) has emerged as a promising alternative because of rapidity and high sensitivity. However, validation of methodologies is required before the issue of standardization can be addressed. In the present study, 109 clinical samples (organ tissue, nasal, and faecal swabs) from pigs experimentally infected with Chlamydia suis were examined by cell culture, nested PCR in the ompA gene region, and two different antigen enzyme-linked immunosorbent assays (ELISAs) in order to compare the diagnostic performance of these methods. Culture and PCR produced the highest proportion of concordant results (kappa coefficient 0.712). Among 99 samples, 34 were positive in both assays, 51 were negative in both assays, 12 culture-negatives were positive in PCR, and only 2 culture-positives were negative in PCR. Thus, the sensitivity and specificity of PCR vs. culture as standard were 94.4% and 81.0%, respectively, whereas the corresponding values for culture vs. PCR as standard were 73.9% and 96.2%, respectively. Both ELISA tests performed considerably weaker. The data underline the potential of PCR as a powerful detection method for chlamydiae.

Animals↗

PubMed2002

Cytomegalovirus in human abortion in Espírito Santo, Brazil.

BACKGROUND: Despite the established implication of human cytomegalovirus (HCMV) in congenital infection, there are still conflicting reports regarding the association of HCMV with spontaneous abortion. Viral antigens and nucleic acid were already described in tissues from abortions cases, but did not indicate HCMV pathogenical role. OBJECTIVES: (1) To access viral seroprevalence (total and IgM antibodies) in pregnant, non-pregnant and in women in abortion process, (2) to evaluate if antigenemia assay can detect active infection in these populations, (3) to detect viral DNA in peripheral leukocytes, and (4) in abortion tissues. STUDY DESIGN: Blood samples from 95 patients in abortion process and from two control groups (40 pregnant and 60 non-pregnant women) were obtained for determination of viral seroprevalence, for detection of antigen and viral DNA by PCR from peripheral leukocytes. Specimens obtained from 88 patients in abortion process, spontaneous or induced, were submitted to gB gene amplification (PCR and nested-PCR). RESULTS: Viral seroprevalence were found in 97.3 with 2.5% of IgM positive cases. Antigenemia assay were negative in all cases, however, viral nucleic acid were found in 6.3 and in 6.0% of the patients in abortion and in control groups, respectively. Nucleic acid in conception tissue was present in 6.6%. CONCLUSION: This high seroprevalence observed is according to previous surveys in Brazil. If active infection due to viral reactivation occurred during the abortion process, it cannot be accessed by antigenemia or anti-IgM assays. Nucleic acid found by PCR in peripheral blood cells enriched with polymorphonuclear cells (PMN) corresponds to viral circulation in immunocompetent person, as similar results were found for the three groups. Although viral DNA had been found in 6.6% from abortion tissues, this result does not support HCMV as a major abortion-related factor as we could not found any correlation between abortion and active HCMV infection.

Abortion, Spontaneous↗

PubMed2002

Detection of Helicobacter pylori in cow's milk.

AIMS: To investigate the existence of Helicobacter pylori in cow's milk as one of the foods which most Japanese children eat. METHODS AND RESULTS: Detection of H. pylori was demonstrated by the semi-nested polymerase chain reaction (PCR), a culture method and electron microscopy. Semi-nested PCR demonstrated the ureA gene of H. pylori in 13 of 18 (72.2%) raw milk samples and in 11 of 20 (55%) commercial pasteurized milk samples. Helicobacter pylori binding immunomagnetic beads with H. pylori-specific goat anti-H. pylori antibody was shown by electron microscopy in both raw and pasteurized milk positive for the ureA gene. Helicobacter pylori was cultured in one raw milk sample, whereas it was not cultured in pasteurized milk samples. CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: There is a possibility that cow's milk is a transmission vehicle in childhood H. pylori infection, although we failed to confirm the survival of H. pylori in pasteurized milk.

Animals↗