排序方式: 共有74条查询结果,搜索用时 15 毫秒
31.
Vaccination with the T cell antigen Mtb 8.4 protects against challenge with Mycobacterium tuberculosis 总被引:18,自引:0,他引:18
Coler RN Campos-Neto A Ovendale P Day FH Fling SP Zhu L Serbina N Flynn JL Reed SG Alderson MR 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(10):6227-6235
The development of an effective vaccine against Mycobacterium tuberculosis is a research area of intense interest. Mounting evidence suggests that protective immunity to M. tuberculosis relies on both MHC class II-restricted CD4(+) T cells and MHC class I-restricted CD8(+) T cells. By purifying polypeptides present in the culture filtrate of M. tuberculosis and evaluating these molecules for their ability to stimulate PBMC from purified protein derivative-positive healthy individuals, we previously identified a low-m.w. immunoreactive T cell Ag, Mtb 8.4, which elicited strong Th1 T cell responses in healthy purified protein derivative-positive human PBMC and in mice immunized with recombinant Mtb 8.4. Herein we report that Mtb 8.4-specific T cells can be detected in mice immunized with the current live attenuated vaccine, Mycobacterium bovis-bacillus Calmette-Guérin as well as in mice infected i.v. with M. tuberculosis. More importantly, immunization of mice with either plasmid DNA encoding Mtb 8.4 or Mtb 8.4 recombinant protein formulated with IFA elicited strong CD4(+) T cell and CD8(+) CTL responses and induced protection on challenge with virulent M. tuberculosis. Thus, these results suggest that Mtb 8.4 is a potential candidate for inclusion in a subunit vaccine against TB. 相似文献
32.
Apoptosis is characterized by DNA strand breaks with a 3'-OH terminus, which are analyzed by terminal deoxy(d)-UTP nick end labeling (TUNEL). Proteinase K digestion is thought to be an essential step in the TUNEL procedure. The effects of decalcifying reagents on general staining and the TUNEL assay for cartilage sections are largely unknown. The effects of these reagents on retention and integrity of DNA in chondrocytes have not been described until now. We evaluated the effects of various decalcifying solutions, including 10% EDTA, 10% citric acid, 5% trichloroacetic acid, 5% acetic acid and a commercial hydrochloric acid-based reagent, on general cartilage staining and the TUNEL assay for cartilage. The effects of proteinase K on nucleus preservation were also examined. Decalcification with 10% EDTA gave the best result for general cartilage staining. Chondrocyte DNA was retained and intact after using this reagent. Decalcification with 10% EDTA is also the safest method of decalcification if the TUNEL assay is applied to cartilage. Proteinase K digestion may have adverse effects on nucleus preservation in cartilage. Awareness of these effects is important whenever the TUNEL assay is applied. 相似文献
33.
PJ?Baker H?Johnston M?Abel HM?Charlton PJ?O'ShaughnessyEmail author 《Reproductive biology and endocrinology : RB&E》2003,1(1):4
During mammalian testis development distinct generations of fetal and adult Leydig cells arise. Luteinising hormone (LH) is
required for normal adult Leydig cell function and for the establishment of normal adult Leydig cell number but its role in
the process of adult Leydig cell differentiation has remained uncertain. In this study we have examined adult Leydig cell
differentiation in gonadotrophin-releasing hormone (GnRH)-null mice which are deficient in circulating gonadotrophins. Adult
Leydig cell differentiation was assessed by measuring expression of mRNA species encoding four specific markers of adult Leydig
cell differentiation in the mouse. Each of these markers (3β-hydroxysteroid dehydrogenase type VI (3βHSD VI), 17β-hydroxysteroid
dehydrogenase type III (17βHSD III), prostaglandin D (PGD)-synthetase and oestrogen sulphotransferase (EST)) is expressed
only in the adult Leydig cell lineage in the normal adult animal. Real-time PCR studies showed that all four markers are expressed
in adult GnRH-null mice. Localisation of 3βHSD VI and PGD-synthetase expression by in situ hybridisation confirmed that these genes are expressed in the interstitial tissue of the GnRH-null mouse. Treatment of animals
with human chorionic gonadotrophin increased expression of 3βHSD VI and 17βHSD III within 12 hours further indicating that
differentiated, but unstimulated cells already exist in the GnRH-null mouse. Thus, while previous studies have shown that
LH is required for adult Leydig cell proliferation and activity, results from the present study show that adult Leydig cell
differentiation will take place in animals deficient in LH. 相似文献
34.
35.
PJ Gokhale 《Biotechnic & histochemistry》2016,91(8):540-548
The extraction of statistically meaningful quantitative information from microscopy images is increasingly important for modern biological research. Obtaining accurate, quantitative information from biological specimens, however, is a complex process that requires optimization of several parameters. One must consider the number of probes, fluorescent channels required, type of plate to be used, number of fields to be acquired and optimal resolution for image acquisition. The extraction of information from images is dependent on and can be aided greatly by careful consideration of the factors involved in the image acquisition process. I summarize here the general principles behind the imaging and software technology that is used to quantify images and highlight particular issues of concern for critically applying image quantitation techniques for research. 相似文献
36.
TE Willnow C Antignac AW Br?ndli EI Christensen RD Cox D Davidson JA Davies O Devuyst G Eichele ND Hastie PJ Verroust A Schedl IC Meij 《Organogenesis》2005,2(2):42-47
Rapid progress in genome research creates a wealth of information on the functional annotation of mammalian genome sequences. However, as we accumulate large amounts of scientific information we are facing problems of how to integrate and relate the data produced by various genomic approaches. Here, we propose the novel concept of an organ atlas where diverse data from expression maps to histological findings to mutant phenotypes can be queried, compared and visualized in the context of a three-dimensional reconstruction of the organ. We will seek proof of concept for the organ atlas by elucidating genetic pathways involved in development and pathophysiology of the kidney. Such a kidney atlas may provide a paradigm for a new systems-biology approach in functional genome research aimed at understanding the genetic bases of organ development, physiology and disease.Key Words: EuReGene, kidney, genome, development, pathophysiology, genetics 相似文献
37.
A covariotide model explains apparent phylogenetic structure of oxygenic photosynthetic lineages 总被引:4,自引:13,他引:4
Lockhart PJ; Steel MA; Barbrook AC; Huson DH; Charleston MA; Howe CJ 《Molecular biology and evolution》1998,15(9):1183-1188
The aims of the work were (1) to develop statistical tests to identify
whether substitution takes place under a covariotide model in sequences
used for phylogenetic inference and (2) to determine the influence of
covariotide substitution on phylogenetic trees inferred for photosynthetic
and other organisms. (Covariotide and covarion models are ones in which
sites that are variable in some parts of the underlying tree are invariable
in others and vice versa.) Two tests were developed. The first was a
contingency test, and the second was an inequality test comparing the
expected number of variable sites in two groups with the observed number.
Application of these tests to 16S rDNA and tufA sequences from a range of
nonphotosynthetic prokaryotes and oxygenic photosynthetic prokaryotes and
eukaryotes suggests the occurrence of a covariotide mechanism. The degree
of support for partitioning of taxa in reconstructed trees involving these
organisms was determined in the presence or absence of sites showing
particular substitution patterns. This analysis showed that the support for
splits between (1) photosynthetic eukaryotes and prokaryotes and (2)
photosynthetic and nonphotosynthetic organisms could be accounted for by
patterns arising from covariotide substitution. We show that the additional
problem of compositional bias in sequence data needs to be considered in
the context of patterns of covariotide/covarion substitution. We argue that
while covariotide or covarion substitution may give rise to
phylogenetically informative patterns in sequence data, this may not always
be so.
相似文献
38.
K. Evangelou J. Bramis I. Peros P. Zacharatos D. Dasiou-Plakida N. Kalogeropoulos PJ Asimacopoulos C. Kittas E. Marinos VG Gorgoulis 《Biotechnic & histochemistry》2004,79(1):5-10
It is well established that p16INK4A protein acts as a cell cycle inhibitor in the nucleus. Therefore, cytoplasmic localization of p16 INK4A usually is disregarded by investigators as nonspecific. Three recent studies reported findings that differ from the current view concerning p16INK4A immunohistochemical localization. All three demonstrated that breast and colon cancers expressing cytoplasmic p16INK4 represent distinct biological subsets. We previously detected in a percentage of non-small cell lung carcinomas simultaneous nuclear and cytoplasmic p16INK4A staining. In view of the reports concerning breast and colon carcinomas, we conducted an ultrastructural re-evaluation of our cases to clarify the specificity of p16INK4A cytoplasmic expression. We observed p16 INK4A immunolocalization in both the nucleus and the cytoplasm of a proportion of tumor cells. Diffuse dense nuclear staining was detected in the nucleoplasm, whereas weaker granular immunoreactivity was observed in the cytoplasm near the rough endoplasmic reticulum. Negative tumor cells also were visible. In the tumor-associated stromal, cells p16INK4A immunoreactivity was detected only in the nuclei. We have demonstrated that p16INK4A cytoplasmic staining is specific and suggest that it represents a mechanism of p16INK4A inactivation similar to that observed in other tumor suppressor genes. 相似文献
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40.
MG Mullender NA Blom M De Kleuver JM Fock WMGC Hitters AMC Horemans CJ Kalkman JEH Pruijs RR Timmer PJ Titarsolej NC Van Haasteren Tol-de MJ Van Jager AJ Van Vught BJ Van Royen 《Scoliosis》2008,3(1):1-14