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81.
Identical allelic losses in mature teratoma and other histologic components of malignant mixed germ cell tumors of the testis 总被引:3,自引:0,他引:3 下载免费PDF全文
Kernek KM Ulbright TM Zhang S Billings SD Cummings OW Henley JD Michael H Brunelli M Martignoni G Foster RS Eble JN Cheng L 《The American journal of pathology》2003,163(6):2477-2484
Teratomas of the testis in post-pubertal patients are histologically diverse tumors that often coexist with other types of germ cell tumors. Using laser capture microdissection and loss of heterozygosity analysis, we investigated the clonality of mature teratoma and its relationship to other components of malignant mixed germ cell tumors to gain potential insight into the histogenetic relationship of teratoma with other germ cell tumor components. All 16 patients had mature teratoma as one component of their mixed germ cell tumors. The other histological subtypes included immature teratoma, seminoma, embryonal carcinoma, yolk sac tumor, and choriocarcinoma. Laser-assisted microdissection was performed on the formalin-fixed, paraffin-embedded tissue. Polymerase chain reaction was used to amplify genomic DNA at specific loci on chromosome 1p36.2 (D1S508), 2q22-32 (D2S156), 9p21-22 (D9S162), 11p13 (D11S903), 12q22-23 (D12S1051), and 18q21 (D18S46). Fourteen of 16 (88%) cases showed allelic loss in one or more components of the mixed germ cell tumors. Fourteen of 16 mature teratomas showed allelic loss in at least one of six microsatellite polymorphic markers analyzed. The frequency of allelic loss in mature teratoma was 50% (7 of 14) with D1S508, 33% (5 of 15) with D2S156, 58% (7 of 12) with D9S162, 43% (6 of 14) with D11S903, 20% (3 of 15) with D12S1051, and 33% (5 of 15) with D18S46. Completely concordant allelic loss patterns between mature teratoma and all of the other germ cell tumor components were seen in 10 of 14 tumors in which mature teratoma showed loss of heterozygosity. Our data support the common clonal origin of mature teratoma with other components of malignant mixed germ cell tumors of the testis. 相似文献
82.
Oval cell proliferation associated with the murine insertional mutation TgN737Rpw. 总被引:4,自引:2,他引:4 下载免费PDF全文
W. G. Richards B. K. Yoder R. J. Isfort P. G. Detilleux C. Foster N. Neilsen R. P. Woychik J. E. Wilkinson 《The American journal of pathology》1996,149(6):1919-1930
The Tg737 gene was identified by its direct association with a transgene-induced insertion mutation in the mouse. This mutation causes pleiotropic phenotypes including a syndrome similar to autosomal recessive polycystic kidney disease in humans. This syndrome, in addition to renal cyst formation, includes the presence of an invariably associated liver abnormality. The liver pathology in TgN737Rpw mice is characterized by a biliary hyperplasia that includes the proliferation of cells that morphologically and immunologically resemble oval cells, a liver progenitor cell. This abnormality is first observed at approximately 5 days of age in the portal region and then progresses into the periportal regions. Additionally, the formation and proliferation of dysplastic ductular structures are observed from the onset of the phenotype. Serum chemistry indicated that the primary defect is likely to be of biliary origin, and hepatic function appears normal in the mutant mice. Therefore, this mutation is unlike other causes of oval cell proliferation in that the hepatic parenchyma is relatively unaffected. The identification of the Tg737 gene associated with this mutation suggests that it functions in regulating the proliferation/differentiation of oval cells within the liver, which further indicates that this gene may function in pathological conditions that include oval cell proliferation, such as hepatocellular carcinogenesis. 相似文献
83.
The airway epithelium is the first cellular component of the lung to be encountered by the particles and pathogens present in inhaled air. In addition to its role as a physical barrier, the immunological activity of the airway epithelium is an essential part of the pulmonary immune system. This means that the symptoms of lung diseases that involve immunological mechanisms are frequently exacerbated by infection of the airway epithelium with respiratory viruses. The virus-induced enhancement of immunological activity in infected epithelial cells is well characterized. However, the effects that contaminants of inhaled air have upon the infectivity and replication of respiratory viruses and the inflammation they cause, are comparatively unknown. In this study, we have shown that pre-exposure of airway epithelial cells to bacterial lipopolysaccharides or a proteolytically active house dust mite allergen, is able to, respectively, inhibit or enhance the level of cellular infection with respiratory syncytial virus and similarly alter virus-induced expression of the inflammatory chemokine interleukin-8. These results suggest that respiratory syncytial virus infection and the inflammation caused by respiratory syncytial virus may be modified by the biologically active contaminants of indoor air. 相似文献
84.
Cloning, expression, and mapping of the Staphylococcus aureus alpha-hemolysin determinant in Escherichia coli K-12. 总被引:7,自引:7,他引:7 下载免费PDF全文
A fragment of Staphylococcus aureus DNA encoding the alpha-hemolysin determinant was cloned from strain Wood 46 by inserting Sau3A-generated genomic DNA fragments between the BamHI sites of the lambda replacement vector L47.1. Phages expressing alpha-hemolysin were detected by overlaying plaques formed from several thousand independent recombinant phage with erythrocytes and looking for zones of hemolysis. One phage expressing alpha-hemolysin was purified and named lambda w alpha 3. This was subsequently shown to contain a 10.2-kilobase pair insert of S. aureus DNA. A 7.6-kilobase pair HindIII fragment encoding the alpha-hemolysin was subcloned from lambda w alpha 3 into the plasmid vector pACYC184 to form the hybrid plasmid pDU1148. Escherichia coli K-12 cells harboring pDU1148 synthesized a low level of alpha-hemolysin which remained associated with the cells and was not secreted into culture supernatants. When the same strain was stabbed onto blood agar plates, no zones of hemolysis were detected after overnight growth at 37 degrees C but hemolysis developed if the plates were left at room temperature for 48 h. By introducing specific deletions or Tn5 insertions into plasmid pDU1148, the alpha-hemolysin gene was mapped to a region within a 3.3-kilobase pair EcoRI-HindIII fragment which was subcloned onto the vector plasmid pBR322. A specific enzyme-linked immunosorbent assay with peroxidase-labeled rabbit anti-alpha-hemolysin antibodies was used to measure the levels of alpha-hemolysin antigen expressed in E. coli K-12 cells harboring pDU1148 or a variety of pDU1148::Tn5 and pDU1148 deletion mutants. 相似文献
85.
Norethisterone treatment to control timing of the IVF cycle 总被引:1,自引:0,他引:1
Wardle P.G.; Foster P.A.; Mitchell J.D.; McLaughlin E.A.; Williams J.A.C.; Corrigan E.; Ray B.D.; McDermott A.; Hull M.G.R. 《Human reproduction (Oxford, England)》1986,1(7):455-457
The use of norethisterone to control the timing of the precedingmenstrual cycle and in consequence the timing of the in-vitrofertilization (IVF) cycle has been evaluated in a therapeuticIVF programme in which oocyte recovery was limited to 2 dayseach week. A consecutive series of 181 cycles after norethisteroneand 29 untreated controls were compared. Menstruation occurred2 3 days after norethisterone as planned in 82% of patientsoverall and in 87% of patients whose menstrual cycle lengthvaried by no more than 2 days about the median. Norethisteronetreatment did not significantly affect the outcome of IVF treatmentcompared with the controls in respect to cycles abandoned (12versus 0%, respectively), peak follicular diameter (mean 18.1mm versus 18.3 mm 48 h before laparoscopy), oocyte recoveryrate (4.6 versus 4.5 per patient), oocyte morphology (63% versus52% mature), or fertilization rate (72 versus 65% of matureoocytes). Clinical pregnancies were too few for comparison (rates27 versus 9% per laparoscopy) but the overall rate (23%) indicatedeffectiveness of the methods. Prior norethisterone treatmentappears to be an effective and useful means of controlling thetiming of the oocyte recovery in IVF treatment. 相似文献
86.
87.
This study provides normative data on 270 child and adolescent psychiatric inpatients using the Bender Recall technique as a measure of short-term visual memory. In addition, the authors present normative data on another immediate recall technique using the Coding section of the WISC-R. These findings are examined in light of age differences and IQ scores. Detailed instructions for administering the Coding Recall technique are presented. 相似文献
88.
Comparison of rapid,automated ribotyping and DNA macrorestriction analysis of Burkholderia pseudomallei 总被引:2,自引:0,他引:2 下载免费PDF全文
Inglis TJ O'Reilly L Foster N Clair A Sampson J 《Journal of clinical microbiology》2002,40(9):3198-3203
An automated ribotyping device (RiboPrinter) was used to determine the ribotypes of a collection of Burkholderia pseudomallei isolates. In a preliminary evaluation with the restriction enzymes BamHI and EcoRI, the protocol with EcoRI was more discriminating. The reproducibilities of the ribotypes obtained with EcoRI (EcoRI ribotypes) were determined by testing three levels of bacterial loads. The performance of the manufacturer's software was assessed by comparing the machine-optimized ribotypes with the type determined from the original gel image analyzed with Bionumerics software. The library of B. pseudomallei EcoRI ribotypes was then compared with the ribotypes obtained by DNA macrorestriction analysis of XbaI digests by pulsed-field gel electrophoresis. The typeability of B. pseudomallei by EcoRI ribotyping was 100%, and the discrimination index was 0.94. The slightly greater discrimination provided by DNA macrorestriction analysis (0.96) was achieved at the expense of a significantly longer processing time of 6 days, although the method was only half the cost of automated ribotyping. Typeability by macrorestriction analysis was lower (97%) unless a thiourea step was added to neutralize the action of Tris-dependent endonucleases. The digital record of B. pseudomallei isolates analyzed thus far provides a useful resource for future epidemiological studies and will help shorten the response time in the event of a further melioidosis outbreak or the deliberate release of B. pseudomallei as a biohazard. 相似文献
89.
Virulence of protein A-deficient and alpha-toxin-deficient mutants of Staphylococcus aureus isolated by allele replacement. 总被引:7,自引:15,他引:7 下载免费PDF全文
The gene coding for protein A (spa) of Staphylococcus aureus 8325-4 has been inactivated by substituting part of the spa coding sequence for a DNA fragment specifying resistance to ethidium bromide. The in vitro-constructed spa::EtBrr substitution mutation was introduced into the S. aureus chromosome by recombinational allele replacement. Southern blot hybridization showed that the in vitro-constructed mutation was present in the chromosomal spa locus. We have previously reported the inactivation of the alpha-toxin gene (hly) by allele replacement with an in vitro-constructed hly::Emr (erythromycin resistance) mutation (M. O'Reilly, J.C.S. de Azavedo, S. Kennedy, and T.J. Foster, Microb. Pathogen. 1:125-138, 1986). A double Spa- Hly- mutant was constructed by transduction. The virulence of Spa- and Hly- mutants was tested by experimental infection of mice. When subcutaneous injections were given, Hly- mutants formed a flat, darkened lesion, whereas Hly+ strains caused a raised, cream lesion. Alpha-toxin was shown to be a major factor in forming subcutaneous lesions and in causing the death of mice injected intraperitoneally. Spa- mutants were slightly less virulent than their Spa+ counterparts, which suggests that protein A is also a virulence factor of S. aureus. 相似文献
90.
Matz PE Foster GD Faith MS Wadden TA 《Journal of consulting and clinical psychology》2002,70(4):1040-1044
Predictors of body image dissatisfaction (BID) among obese people are poorly understood. In 79 obese women seeking weight reduction, associations with BID of self-esteem, youth teasing, adult teasing, and internalization of sociocultural appearance standards (ISAS) were studied. Analyses revealed that only self-esteem, adult teasing, and ISAS predicted BID. Results highlight the importance of adulthood self-esteem and interpersonal-cultural context--rather than childhood experiences--in predicting adulthood BID. 相似文献