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Recurrent respiratory papillomatosis (RRP) is the most common benign tumour of the larynx, affecting both children and adults. We present a series of 25 patients, including 10 cases of juvenile multiple, 8 cases of adult solitary, and 7 cases of adult multiple RRP. Biopsy tissue from each patient was screened by Southern blot hybridization and polymerase chain reaction for the presence of human papillomavirus (HPV) DNA. Sera from patients and age- and sex-matched controls were tested for the presence of HPV-specific antibodies using a synthetic pep-tide derived from the minor capsid protein (L2) of HPV 6/11. By Southern blot hybridization and/or polymerase chain reaction, biopsies from all patients were positive for HPV 6/11 DNA. There was no difference in antibody response between cases and controls. Female cases and controls had significantly higher antibody titers than male subjects. A correlation was observed between the HPV-specific antibody level and the number of surgery-necessitating recurrences. © 1994 Wiiey-Liss, Inc.  相似文献   
13.
BACKGROUND: An antibody method based on absorption of serum with cytomegalovirus (CMV) glycoprotein B (gB) was developed for detection of infection during clinical trials of CMV gB vaccine. Previous study showed that this method detected the antibody response to infection and was negative with vaccine induced immunity. OBJECTIVES: In an ongoing efficacy trial of CMV gB vaccine the ability of the gB-absorbed CMV IgG assay to detect CMV infection was assessed and compared with viral culture results. STUDY DESIGN: Two hundred and ninety two healthy, seronegative young women in a phase II, double-blind, placebo-controlled, clinical trial of recombinant CMV gB vaccine (sanofi pasteur) with MF59 adjuvant (Chiron) were randomized to receive CMV gB vaccine or placebo (1:1) on a 0, 1 and 6 month schedule. Participants were screened every 3 months for CMV infection using the gB-absorbed CMV IgG assay, and a subgroup was also screened for infection with viral cultures. Viral culture (urine, vaginal swab and saliva) was used to confirm CMV infection in all subjects with a positive gB-absorbed CMV IgG result. RESULTS: Evidence of CMV infection (gB-absorbed CMV IgG levels>or=5.0 AU/ml) was found in 23/292 (7.88%) study participants. The gB-absorbed CMV IgG levels of their first positive serum ranged from 15.7 to 251.0 AU/ml with a mean of 77.0 AU/ml and a median of 44.9 AU/ml. Cytomegalovirus was isolated from all 23 of them from culture specimens collected after their first positive gB-absorbed CMV IgG. The time to first CMV positive culture from first positive gB-absorbed CMV IgG ranged from 0 to 12 weeks with a median of 2 weeks. CONCLUSIONS: The gB-absorbed CMV IgG assay detects CMV infection in CMV gB vaccine clinical trials earlier and more rapidly than virus culture and does not reveal whether subjects received CMV gB vaccine or placebo.  相似文献   
14.
Isolation and rapid identification of Haemophilus ducreyi.   总被引:2,自引:3,他引:2       下载免费PDF全文
During a 2-month period, 62 strains of Haemophilus ducreyi were isolated from 168 genital lesions and 2 lymph node aspirates. Of these strains, 22 were found on both chocolate agar and fetal bovine serum agar supplemented with vancomycin, 29 were found only on chocolate agar, and 9 were found only on fetal bovine serum agar. Two additional strains were isolated on sheep blood agar. All of these isolates were correctly identified with the RapID NH system (Innovative Diagnostic Systems, Inc., Decatur, Ga.) a new identification kit that has a database for Haemophilus, Neisseria, and other genera that include fastidious gram-negative bacilli.  相似文献   
15.
The role of natural versus acquired immunity to Leishmania aethiopica infection in humans is the focus of our studies. We found in previous studies that mononuclear cells from nonexposed healthy Swedish donors responded to Leishmania antigen stimulation by proliferation and gamma interferon production. The main cell type responding was CD3 CD16/56+ natural killer (NK) cells. These findings led us to suggest that the potential to produce a rapid, nonacquired NK cell response may be a protective phenotype. In order to test this hypothesis, an area in Ethiopia where Leishmania is endemic was selected, and peripheral blood mononuclear cells were obtained from individuals who had lived in the area most of their lives but had no evidence of past or present leishmaniasis. Their responses were compared with those of confirmed leishmaniasis patients from the same region with active lesions or cured leishmaniasis lesions. Cells from these donors were stimulated in vitro with L. aethiopica antigen. Responses were measured by proliferation, cytokine production, and phenotype analysis by fluorescence-activated cell sorting. The association of NRAMP1 alleles with the studied phenotype and susceptibility to L. aethiopica-induced leishmaniasis was also evaluated. The results show that Leishmania antigens can induce NK cell and CD8+-T-cell responses in vitro. This is clearly seen in proliferating cells from the cured (immune) individuals and the apparently protected controls from the area of endemicity. It contrasted with the reactivity of the patients, where some NK proliferation was coupled with enhanced CD4+-T-cell proliferation. We conclude from these observations that NK cells and CD8+ cells proliferating in response to Leishmania stimulation are involved in protection from and healing of (Ethiopian) cutaneous leishmaniasis; however, such mechanisms appear to be unrelated to the NRAMP1 host resistance gene.  相似文献   
16.
The hepatitis B virus (HBV) genome contains a specific DNA binding site for the glucocorticoid receptor. Using DNase I footprinting, this binding site was localized at HBV map positions 341-370 clockwise from the EcoRI site. The DNA sequence protected in the footprint contains two tandem copies of the GRE core hexanucleotide 5'-TGTTCCT-3'. Deletion analysis and reconstruction experiments in plasmid expression vectors demonstrated that this glucocorticoid receptor binding sequence serves as a signal for augmenting glucocorticoid-dependent activity of the HBV enhancer, which is located approximately 730 nucleotides downstream in the HBV genome. Even though it does not serve as an independent enhancer element, the HBV glucocorticoid receptor domain can therefore be categorized as a functional GRE.  相似文献   
17.
There have been recent reports of human embryonic stem cell (hESC) lines developing chromosomal aberrations after long-term culture, indicating an unstable genomic status due to the in vitro milieu. This raises concern, since it would limit their use in therapeutics. In this study the chromosomal status of five well-characterized hESC lines, SA002, SA002.5, AS034.1.1, SA121 and SA461, was monitored during long-term in vitro culture. The criteria of defined hESCs were met by all of the five hESC lines (four diploid and one trisomic for chromosome 13). The genomes were screened for chromosomal aberrations and rearrangements using comparative genomic hybridization (CGH), interphase fluorescence in situ hybridization (FISH) and traditional karyotyping on several occasions while in culture. The genomic integrity was shown to be maintained after repeated freeze-thaw procedures and continuous culture in vitro for up to 22 months (148 passages). We discuss the most common de novo chromosomal aberrations reported in hESCs, as well as their possible origin.  相似文献   
18.
19.
1.5-T surface-coil MRI of the knee   总被引:1,自引:0,他引:1  
Five normal knees and 20 knees with suspected abnormalities involving the menisci or articular surfaces were examined with high-resolution surface-coil MRI. Surgical correlation was available in 15 cases. Signal-to-noise ratios were optimized using a field strength of 1.5 T and a round 7.6-cm surface coil. Spatial resolution was maximized by using fields of view reduced to as small as 8 cm. Separate examinations of the medial and lateral joint compartments were performed with the surface coil positioned vertically adjacent to the meniscus of interest. Ten meniscal tears were identified using sagittal and coronal images. T1-weighted images were adequate to detect most meniscal tears, and T2-weighted images were useful for providing an "arthrogram effect" in the presence of a joint effusion. Extrameniscal lesions that were examined included osteonecrosis of the femoral condyle, subchondral cysts, rheumatoid arthritis, degenerative arthritis, and anterior cruciate ligament tears. MRI was useful in determining the integrity of articular cartilage overlying defects in the subchondral bone and in detecting gross cartilage lesions in arthritis, but was less sensitive than arthroscopy in evaluating moderate changes in the hyaline cartilage.  相似文献   
20.
A model for concordance in a binary measure that does not rely on the assumption of an underlying latent liability dichotomized about a threshold has been demonstrated for twin pairs [Hannah et al, 1983]. It is extended here to pedigrees of arbitrary structure by making an assumption that is, for small incidence rates, almost equivalent to postulating that relative risks are multiplicative. The model is applied to the workshop data to determine the extent to which the known structure of the simulated models can be recovered.  相似文献   
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