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51.
52.
The second instance of a prenatally diagnosed fetus of D trisomy is reported in a 45-year-old woman. The fetus had bilateral hare lip and cleft palate, arrhinencephaly, and numerous other malformations. 相似文献
53.
Staphylococcus epidermidis has been reported to bind to a number of host cell extracellular matrix proteins, including fibronectin. Here we report the identification of a fibronectin-binding protein from S. epidermidis. A phage display library of S. epidermidis genomic DNA was constructed and panned against immobilized fibronectin. A number of phagemid clones containing overlapping inserts were identified, and one of these clones, pSE109FN, contained a 1.4-kb insert. Phage pSE109FN was found to bind to fibronectin but not to collagen, fibrinogen, laminin, or vitronectin. However, pSE109FN also bound to heparin, hyaluronate, and plasminogen, although to a lesser extent than it bound to fibronectin. Analysis of The Institute for Genomic Research S. epidermidis genome sequence database revealed a 1.85-kb region within a putative 30.5-kb open reading frame, to which the overlapping DNA inserts contained within the fibronectin-binding phagemids mapped. We have designated the gene encoding the fibronectin-binding domain embp. A recombinant protein, Embp32, which encompassed the fibronectin-binding domain of Embp, blocked the binding of S. epidermidis, but not the binding of Staphylococcus aureus, to fibronectin. In contrast, a recombinant protein, FnBPB[D1-D4], spanning the fibronectin-binding domain of the S. aureus fibronectin-binding protein FnBPB, blocked binding of S. aureus to fibronectin but had a negligible effect on the binding of S. epidermidis. 相似文献
54.
55.
Sanna MP Sanna E De Las Heras M Leoni A Nieddu AM Pirino S Sharp JM Palmarini M 《Journal of comparative pathology》2001,125(2-3):145-152
Bronchiolo-alveolar carcinoma has been described in man and in several animal species, including cattle, dogs, opossums, goats and sheep. In sheep, a bronchiolo-alveolar carcinoma, known as ovine pulmonary carcinoma (OPC), is caused by jaagsiekte sheep retrovirus (JSRV), an exogenous type D retrovirus. In the mid-1980s, a severe outbreak of a disease resembling OPC was described in captive Sardinian moufflon (Ovis musimon). In the present study, the use of polymerase chain reaction (PCR) amplification of nucleic acids extracted from archival material established that JSRV was associated with OPC in affected moufflon. JSRV was detected in the lungs and mediastinal lymph nodes. Immunohistochemical and in-situ PCR demonstrated that in the lungs, JSRV proviral DNA was localized in transformed and untransformed type II pneumocytes and in the alveolar macrophages. In the mediastinal lymph nodes, JSRV DNA was mainly located in the cortical follicles and paracortex. These data suggest that JSRV is the cause of OPC in Sardinian moufflon, as it is in Sardinian sheep. 相似文献
56.
Zelinski-Wooten MB; Slayden OD; Chwalisz K; Hess DL; Brenner RM; Stouffer RL 《Human reproduction (Oxford, England)》1998,13(2):259-267
Large doses of antiprogestin typically disrupt menstrual cyclicity. A
chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which
permits continued menstrual cyclicity but alters gonadal- reproductive
tract activity, was established. Rhesus monkeys received vehicle (n = 6) or
0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight
daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and
gonadotrophin profiles were normal during cycles involving vehicle and 0.01
and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle
oestradiol and gonadotrophin surges, and subsequent progesterone
production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied
by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half
the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group
were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of
C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and
cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily
treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in
macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed
ovarian cyclicity, menstruation was disrupted in some animals. Increasing
the dose to 0.1 mg/kg antagonized pituitary function and resulted in
anovulation and amenorrhoea. A chronic low-dose regimen of the
antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity,
has potential as a contraceptive in women.
相似文献
57.
Specific fragments of Adenovirus 5 DNA were produced by digestion of intact, 32P-labeled viral DNA with restriction endonucleases Eco R1 and and Hpa 1. The kinetics of renaturation of each fragment and of complete Adenovirus 5 DNA were measured in the presence of DNA extracted from four lines of Adenovirus 5-transformed rodent cells and from nontransformed control cells. All four transformed cell lines contained sequences homologous to the Hpa 1 fragment comprising the left 4% of the viral genome, but varied in the other Adenovirus 5 DNA sequences which were present: three lines of transformed cells contain segments of DNA extending from the left hand end to points 35, 40, and 12% along the viral genome and carry no other Adenovirus 5 DNA sequences. The fourth line also contains sequences homologous to the left half of the viral genome, but these could not be precisely defined. Therefore, the gene(s) encoded by the left end of Adenovirus 5 DNA must specify any viral gene functions expressed in transformed cells.Separated strands of the three Eco R1 fragments and certain Hpa 1 fragments of 32P-labeled Adenovirus 5 DNA were hybridized with unlabeled, cytoplasmic RNA extracted from each of the four transformed cell lines. In each case, about 10% only of the r strand sequences of the largest Eco R1 fragment were complementary to transformed cell RNA. These sequences have been mapped to the left end of the viral genome using Hpa 1 fragment strands. The same sequences are shown to be expressed as mRNA during the early phase of an Adenovirus 5 lytic infection. 相似文献
58.
A murine model of bone marrow micrometastasis in breast cancer 总被引:3,自引:0,他引:3
Murphy BO Joshi S Kessinger A Reed E Sharp JG 《Clinical & experimental metastasis》2002,19(7):561-569
Bone marrow (BM) is one of the most common sites and often the first clinical indication of metastatic progression of breast
cancer. Multivariate analyses have shown that the presence of cytokeratin positive tumor cells in the marrow of women with
newly diagnosed stage I, II or III breast cancer is an independent predictor of survival. The objective of this study was
to develop an orthotopic model of spontaneous BM metastasis to facilitate studies of this process. A murine mammary adenocarcinoma
cell line, Clone 66, was transduced with the neomycin resistance gene (Cl66neo) and injected orthotopically into female Balb/c mice. Polymerase chain reaction (PCR) for the neo gene performed on BM cells
harvested from tumor bearing mice demonstrated as few as 102 injected tumor cells produced BM micrometastases at 4 weeks post-injection. Small foci of tumor cells were identified in
the mammary fatpad (mfp) without gross evidence of primary tumors. Higher doses of tumor cells produced BM micrometastases,
detectable by PCR, at one week post-injection. Constructs containing green fluorescent protein (GFP) and the neomycin resistance
gene (neo) were also transduced into Clone 66 cells (Cl66-GFPneo) and injected into the mfp. GFP transduced tumor cells were identified in multiple tissues in addition to BM by flow cytometric
analysis (FACS) but less 13% of the animals developed gross metastases. This model is a clinically relevant tool for the analysis
of organ specificity of metastasis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
59.
60.
Experimental autoimmune thyroiditis (EAT) is a chronic inflammatory autoimmune disease that can be induced in genetically susceptible animals by immunization with mouse thyroglobulin (MTg) in an appropriate adjuvant or by the adoptive transfer of MTg-sensitized donor spleen cells, activated in vitro with MTg, into naive recipients. In the adoptive transfer model used in our laboratory, donor cells activated with MTg alone induce a relatively mild chronic lymphocytic form of EAT (L-EAT), in which the thyroid infiltrate consists primarily of mononuclear cells, and the thyroid inflammation persists for several months. When the same donor cells are activated with MTg together with anti-IL-2R and/or IL-12, a more severe and histologically distinct granulomatous form of EAT is induced in recipient mice. In addition to having distinct histopathologic features, granulomatous EAT (G-EAT) differs from L-EAT in that granulomatous thyroid lesions are not chronic. After reaching maximal severity 21 days after cell transfer, G-EAT thyroid lesions either resolve or the thyroids become atrophic and fibrotic by day 35. In this review, the histopathologic features of G-EAT and L-EAT are described, and our studies with the adoptive transfer G-EAT model which have focused on the mechanisms involved in induction of G-EAT in mice, and the evolution of G-EAT lesions to resolution of inflammation or fibrosis, are reviewed. 相似文献