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31.
S A Holland L C Hutton F N McKenzie 《Journal l'Association canadienne des radiologistes》1989,40(2):94-97
The chest radiographic findings and pulmonary radionuclide studies of four patients who underwent heart-lung transplantation between May 1983 and June 1986 were reviewed retrospectively. The two long-term survivors both developed bronchiolitis obliterans (presenting at 32 months postoperatively in the first patient and 14.5 months postoperatively in the second). The etiology of this is likely to be multifactorial and includes pulmonary rejection which may develop without concomitant cardiac rejection. The radiologist must be alert to this complication in heart-lung transplantation. The chest radiographs in our two patients showed diminution of peripheral bronchovascular markings and overinflation. The importance of careful screening of the radiographs of potential donors to detect pneumonia is emphasized. In one patient, a unilateral pneumothorax spread contralaterally due to the absence of normal anatomic barriers. The "reimplantation response" was not a prominent feature and was seen in one patient only. This response has been observed in heart-lung transplant recipients during the second postoperative week. The radiologic appearance is that of interstitial edema not explained by any clinical or hemodynamic findings. 相似文献
32.
Long-term persistent vesicular stomatitis virus and rabies virus infection of cells in vitro. 总被引:25,自引:0,他引:25
J J Holland L P Villarreal R M Welsh M B Oldstone D Kohne R Lazzarini E Scolnick 《The Journal of general virology》1976,33(2):193-211
BHK 21 carrier cells persistently infected with VSV Indiana for over 2 years have been shedding generally very low levels of mature infectious virus or mature T particles (averaging less than one-hundredth p.f.u./cell/day) yet most cells are producing virus antigens and are resistant to homologous superinfection. However, large amounts of biologically active T particle RNP can be recovered from cytoplasmic extracts of these carrier cells even at times when they are shedding no detectable infectious virus. This recovered cytoplasmic RNP replicates (with helper B virions) to produce mature T particles, interferes strongly after DEAE dextran-facilitated uptake and, together with B virions, allows the establishment of a persistent carrier state in exposed cells. No 'provirus' DNA copies of the VSV RNA genome are detectable (less than 1/40 copy/cell or I copy per 40 cells) in carrier cells after more than 2 years of persistent infection, and all transfection attempts have failed using DNA from these VSV carriers or DNA from carrier cells persistently infected with some other negative strand RNA viruses (measles, mumps, LCM, influenza, rabies). Infectious viruses shed after more than I year from carrier cells originally infected with wild-type B virions are small plaque mutants showing a slight temperature sensitivity. Cured cell populations can be obtained from the long term VSV carrier culture by cloning in the presence or absence of antiviral antibody. 相似文献
33.
A differential efficiency of adenovirus-mediated in vivo gene transfer into skeletal muscle cells of different maturity 总被引:8,自引:0,他引:8
Acsadi Gyula; Jani Agnes; Massie Bernard; Simoneau Maude; Holland Paul; Blaschuk Katharine; Karpati George 《Human molecular genetics》1994,3(4):579-584
High titre (10111012 pfu/ml) suspensions of autonomouslyreplication-defective type 5 human adenovirus (AV) recombinantswith different reporter gene inserts (CMV-Luciferase (Lux),CMV-ß-galactosidase (Lac Z), RSV-Lux and RSV-Lac Z)were injected Into intact quadrlceps muscles of 15 dayold (Group 1) or 3545 day old (Group 2) normal mice,as well as regenerating adult mouse muscles (Group 3) and 35day old mdx muscles (Group 4). The expression of the reportergenes was quantitated 10 days and 2 months later. At 10 dayspostinjection all reporter gene expression was very high inthe neonatally injected (Group 1) muscles. In Group 2 musclesthe transduction was markedly less. In Group 3 muscles the geneexpression was significantly better than in the Group 2 muscles.In adult mdx muscles (Group 4) where spontaneous regenerationis usually present, the results were similar to those in Group3 animals. At 2 months post-injection in Group 1 animals, theRSV-Lux expression was even higher than at 10 days postinjection.The cell surface density of 相似文献
34.
Lai AC Chambers TM Holland RE Morley PS Haines DM Townsend HG Barrandeguy M 《Archives of virology》2001,146(6):1063-1074
Summary. We reported previously that equine-2 influenza A virus (H3N8) had evolved into two genetically and antigenically distinct
“Eurasian” and “American” lineages. Phylogenetic analysis, using the HA1 gene of more recent American isolates, indicated
a further divergence of these viruses into three evolution lineages: A South American lineage, a Kentucky lineage, and a Florida
lineage. These multiple evolution pathways were not due to geographic barriers, as viruses from different lineages co-circulated.
For the Kentucky lineage, the evolution rate was estimated to be 0.89 amino acid substitutions per year, which agreed with
the previously estimated rate of 0.8. For the South American lineage, the evolution rate was estimated to be only 0.27 amino
acid substitutions per year. This low evolution rate was probably due to a unique alternating Ser138 to Ala138 substitutions
at antigenic site A. For the Kentucky lineage, there was a preference for sequential nonsynonymous substitutions at antigenic
site B, which was also a “hot spot” for amino acid substitutions. Convalescent sera had minimal cross-reactivity to viruses
of different lineages, indicating antigenic distinctions among these viruses. In contrast to human H3N2 viruses, our results
suggested that the evolution of equine-2 influenza virus resembled the multiple evolution pathways of influenza B virus.
Accepted December 14, 2000 Received September 19, 2000 相似文献
35.
High-throughput SNP allele-frequency determination in pooled DNA samples by kinetic PCR 总被引:19,自引:1,他引:19
We have developed an accurate, yet inexpensive and high-throughput, method for determining the allele frequency of biallelic polymorphisms in pools of DNA samples. The assay combines kinetic (real-time quantitative) PCR with allele-specific amplification and requires no post-PCR processing. The relative amounts of each allele in a sample are quantified. This is performed by dividing equal aliquots of the pooled DNA between two separate PCR reactions, each of which contains a primer pair specific to one or the other allelic SNP variant. For pools with equal amounts of the two alleles, the two amplifications should reach a detectable level of fluorescence at the same cycle number. For pools that contain unequal ratios of the two alleles, the difference in cycle number between the two amplification reactions can be used to calculate the relative allele amounts. We demonstrate the accuracy and reliability of the assay on samples with known predetermined SNP allele frequencies from 5% to 95%, including pools of both human and mouse DNAs using eight different SNPs altogether. The accuracy of measuring known allele frequencies is very high, with the strength of correlation between measured and known frequencies having an r(2) = 0.997. The loss of sensitivity as a result of measurement error is typically minimal, compared with that due to sampling error alone, for population samples up to 1000. We believe that by providing a means for SNP genotyping up to thousands of samples simultaneously, inexpensively, and reproducibly, this method is a powerful strategy for detecting meaningful polymorphic differences in candidate gene association studies and genome-wide linkage disequilibrium scans. 相似文献
36.
Linda Z Holland Kristen A Panfilio Roger Chastain Michael Schubert Nicholas D Holland 《Developmental dynamics》2005,233(4):1430-1443
In vertebrate development, Wnt/beta-catenin signaling has an early role in specification of dorsal/anterior identity and a late one in posterior specification. To understand the evolution of these roles, we cloned beta-catenin from the invertebrate chordate amphioxus. The exon/intron organization of beta-catenin is highly conserved between amphioxus and other animals including a cnidarian, but not Drosophila. In development, amphioxus beta-catenin is concentrated in all nuclei from the 16-cell stage until the onset of gastrulation when it becomes undetectable in presumptive mesendoderm. Li(+), which up-regulates Wnt/beta-catenin signaling, had no detectable effect on axial patterning when applied before the late blastula stage, suggesting that a role for beta-catenin in specification of dorsal/anterior identity may be a vertebrate innovation. From the mid-gastrula through the neurula stage, the highest levels of nuclear beta-catenin are around the blastopore. In the early neurula, beta-catenin is down-regulated in the neural plate, but remains high in adjacent non-neural ectoderm. Embryos treated with Li(+) at the late blastula stage are markedly posteriorized and lack a neural plate. These results suggest that in amphioxus, as in vertebrates, down-regulation of Wnt/beta-catenin signaling in the neural plate is necessary for maintenance of the neuroectoderm and that a major evolutionarily conserved role of Wnt/beta-catenin signaling is to specify posterior identity and pattern the anterior/posterior axis. 相似文献
37.
MMTV-like env gene sequences in human breast cancer 总被引:4,自引:0,他引:4
Summary. We have previously detected an MMTV env gene-like 660 bp sequence in 38% of human breast cancers, but not in normal tissues or other tumors. In this communication
we report the sequences from eleven tumors and three breast cancer cell lines, and compare them to four strains of MMTV and
to the known endogenous retroviral sequences. The breast cancer sequences were highly homogenous to the MMTV’s, but not to
the endogenous sequences suggesting an exogenous origin.
Received January 11, 2000 Accepted July 3, 2000 相似文献
38.
Fluorescent antibody test kit for rapid detection and identification of members of the Bacteroides fragilis and Bacteroides melaninogenicus groups in clinical specimens. 总被引:3,自引:0,他引:3 下载免费PDF全文
The Fluoretec fluorescent antibody test kit (Pfizer Inc., New York, N.Y.), developed for the rapid detection of members of the Bacteroides fragilis and B. melaninogenicus groups, was evaluated by testing 58 stock cultures and 76 clinical specimens. The test reagents detected 100% of 40 B. fragilis and B. thetaiotaomicron stock culture strains, although only 22% of 18 B. vulgatus, B. distasonis, and B. ovatus strains showed positive fluorescence. The 76 clinical specimens were evaluated by examining fluorescent antibody-stained smears of 49 specimens of purulent material and smears of 27 blood cultures which were positive for gram-negative bacilli by Gram stain or subculture. The fluoretec reagent detected members of the B. fragilis group in 28 (97%) of the 29 specimens of purulent material and all (100%) of the 16 blood cultures in which these anaerobes were demonstrated by culture. Overall, the Fluoretec reagent detected members of B. fragilis group in 44 (98%) of the 45 clinical specimens which were shown by culture to contain these anaerobes. Two of the 76 clinical specimens gave positive fluorescence for members of the B. fragilis group but failed to yield these organisms by culture. Members of the B. melaninogenicus group were detected by culture in 15 specimens and in each case their presence was demonstrated by the Fluoretec reagent. No members of the B. melaninogenicus group were isolated from five clinical specimens that gave positive fluorescence with the B. melaninogenicus reagent. 相似文献
39.
RNA synthesis in BHK 21 cells persistently infected with vesicular stomatitis virus and rabies virus. 总被引:3,自引:0,他引:3
Virus-induced RNA synthesis was studied in BHK 21 cells persistently infected with vesicular stomatitis virus (VSV) and rabies virus by labelling RNA synthesized in the presence of antinomycin D. During persistent infection the species of messenger RNA synthesized were similar in size and relative proportions to those seen during acute infection, but there were some minor differences. Full-sized B virion RNA was generally not detected during persistent infection, and new species (probably DI virion RNA) appeared. 相似文献
40.
Defective interfering particles from poliovirus vaccine and vaccine reference strains 总被引:2,自引:0,他引:2
Defective interfering (DI) viral particles have been found to be associated with attenuated oral poliovirus vaccine and also with poliovirus vaccine reference strains. The DI particles replicate in low-passage human fibroblastic cells, the BSC-1 line of monkey kidney cells as well as in HeLa cells. DI particles of the attenuated polioviruses are generated after relatively few serial, high multiplicity passages of cloned, DI-free vaccine virus, whereas virulent strains of poliovirus generate a significant number of DI only after a large number of passages. 相似文献