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11.
12.
S.-H. Kung S.-F. Wang C.-W. Huang C.-C. Hsu H.-F. Liu J.-Y. Yang 《Clinical microbiology and infection》2007,13(8):782-787
Enterovirus 71 (EV71) infections can lead to devastating clinical outcomes in children, with an increasing number of severe cases worldwide. The genetic and antigenic variability of EV71 strains isolated in Taiwan in 1998-2005 was evaluated using partial nucleotide sequence analysis of the VP1 gene and the neutralisation assay. Phylogenetic analyses revealed that most EV71 isolates from the 1998 epidemic belonged to sub-genogroup C2, with a minority belonging to sub-genogroup B4. Between 1999 and 2003, isolates belonging to sub-genogroup B4 predominated, followed by a change to sub-genogroup C4 in 2004 and 2005. Antibodies raised in rabbits or collected from infected patients were able to neutralise EV71 virus stocks at high dilutions, regardless of the sub-genogroup of the virus being challenged. The presence of phylogenetically distinct yet antigenically similar populations of EV71 in Taiwan is of concern in the context of herd immunity and vaccine development. 相似文献
13.
Dal Zotto L; Quaderi NA; Elliott R; Lingerfelter PA; Carrel L; Valsecchi V; Montini E; Yen CH; Chapman V; Kalcheva I; Arrigo G; Zuffardi O; Thomas S; Willard HF; Ballabio A; Disteche CM; Rugarli EI 《Human molecular genetics》1998,7(3):489-499
We have recently reported isolation of the gene responsible for X- linked
Opitz G/BBB syndrome, a defect of midline development. MID1 is located on
the distal short arm of the human X chromosome (Xp22. 3) and encodes a
novel member of the B box family of zinc finger proteins. We have now
cloned the murine homolog of MID1 and performed preliminary expression
studies during development. Mid1 expression in undifferentiated cells in
the central nervous, gastrointestinal and urogenital systems suggests that
abnormal cell proliferation may underlie the defect in midline development
characteristic of Opitz syndrome. We have also found that Mid1 is located
within the mouse pseudoautosomal region (PAR) in Mus musculus , while it
seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a
recent acquisition of the M. musculus PAR. Genetic and FISH analyses also
demonstrated a high frequency of unequal crossovers in the murine PAR,
creating spontaneous deletion/duplication events involving Mid1. These data
provide evidence for the first time that genetic instability of the PAR may
affect functionally important genes. In addition, we show that MID1 is the
first example of a gene subject to X-inactivation in man while escaping it
in mouse. These data contribute to a better understanding of the molecular
content and evolution of the rodent PAR.
相似文献
14.
A Lazaris-Karatzas M R Smith R M Frederickson M L Jaramillo Y L Liu H F Kung N Sonenberg 《Genes & development》1992,6(9):1631-1642
Translation initiation factor eIF-4E binds to the eukaryotic mRNA 5' cap structure (m7 GpppN, where N is any nucleotide). eIF-4E is a limiting factor in translation and plays a key role in regulation of translation. We have shown previously that overexpression of eIF-4E in rodent fibroblasts results in tumorigenic transformation. eIF-4E also exhibits mitogenic activity when microinjected into serum-starved NIH-3T3 cells. To understand the mechanisms by which eIF-4E exerts its mitogenic property, we examined the involvement of the Ras signaling pathway in this activity. Here, we report that Ras is activated in eIF-4E-overexpressing cells, as the proportion of GTP-bound Ras is increased. Overexpression of the negative effector of cellular Ras, GTPase activating protein, causes reversion of the transformed phenotype. Furthermore, we show that neutralizing antibodies to Ras, or a dominant-negative mutant of Ras, inhibit the mitogenic activity of eIF-4E. We conclude that eIF-4E exerts its mitogenic and oncogenic activities by the activation of Ras. 相似文献
15.
Regulation of Growth and Proliferation in B Cell Subpopulations 总被引:18,自引:0,他引:18
16.
Winston Verbi Melvyn F. Greaves Claudio Schneider Kristian Koubek George Janossy Harald Stein Patrick Kung Gideon Goldstein 《European journal of immunology》1982,12(1):81-86
Monoclonal antibodies OKT11 (γ1) and OKT11A (γ2) are described and appear to have similar binding specificities. They bind, in immunofluorescence, with >95% of infant thymocytes, staining both cortical and medullary cells, 65-80% of blood lymphocytes and selectively stain the T cell-dependent paracortical areas of tonsil. A small proportion (9-12%) of bone marrow lymphocytes stain, but this population excludes the terminal transferase-positive cells. Both the γ1 and γ2 antibodies stain the surface membrane Ig-negative lymphocytes in blood and tonsil and are able to block sheep E rosette formation (to normal or leukemic T cells). In contrast, other monoclonal anti-T reagents tested (OKT1, OKT3, OKT4, OKT6, OKT8, OKT9, OKT10) did not block E rosette formation. E rosette formation and OKT11 binding are coincident on T-ALL cell lines and both are trypsin-sensitive. In a series of 145 leukemias and 26 leukemic cell lines investigated, only leukemias with a T cell phenotype including E rosette positivity were reactive with OKT11 and OKT11A. OKT11A binds to a polypeptide of approximately 50000 molecular weight on thymic lymphocytes. This structure may carry the recognition site for sheep erythrocytes. These antibodies provide additional useful markers for T cell analysis and are of potential therapeutic value. 相似文献
17.
18.
In neurodegenerative diseases, such as Alzheimer's disease or HIV encephalitis, neuronal DNA fragmentation has been observed at unexpected high frequencies, without definitive evidence for activation of an irreversible apoptotic pathway. The wobbler mouse is a suggested genetic model of neurodegenerative disease. The mutant mouse develops normally until the fourth week of age when atrophy and weakness of forelimb muscles become apparent. There is a slow progression of the disease and wobbler mice may survive for several months. Spinal cord examination reveals the presence of several motoneurons with perikaryal vacuolar degeneration. In this study, we observed, using terminal dUTP nick-end-labelling staining in mutant spinal cord sections, a massive although very transient DNA fragmentation in different cell types, including glial cells and motoneurons, before the apparition of any clinical symptoms. In older wobbler mice, this DNA fragmentation had completely disappeared and the majority of motoneurons survived. To our knowledge, this is the first example of a massive and transient DNA fragmentation in the central nervous system during the early course of a neurodegenerative disease. 相似文献
19.
Chen Z Fisher R Li B Kamata T Kung H Lautenberger J Rhim J 《International journal of oncology》1997,10(6):1179-1184
We investigated the inhibitory effects of intrasplenic combination therapy with OK-432 and recombinant interleukin-2 (IL-2) on liver metastasis of colorectal carcinoma. Intrasplenic administration group significantly inhibited the development of liver metastasis compared with subcutaneous administration group (p<0.05). Combination therapy significantly inhibited the development of subclinical liver metastasis compared with that in the control group. Combination therapy decreased the percentage of cells expressing CD8a, which may be a part of effective factors of combination therapy, and improved overall survival rate. These findings suggested intrasplenic combination therapy with OK-432 and IL-2 might be effective in inhibiting liver metastasis of colorectal carcinoma. 相似文献
20.
OBJECTIVE: The present study sought to examine use prevalence and factors associated with use of analgesic and psychotropic medications in community-dwelling older people with chronic non-malignant pain. METHOD: The study group comprised 193 community-dwelling older people with daily chronic non-malignant pain who were selected from a random sample of 1,000 older people in Melbourne. RESULTS: The use prevalence for the study group was 63% for analgesics and 39% for psychotropic medications, which is higher than the general older population without chronic pain (p < 0.00001). More women with chronic pain used analgesics, while psycho-social factors such as problems with sleeping and living at home alone were found to be associated with an increased use of psychotropic medications. CONCLUSION: A high proportion of community-dwelling older people with chronic non-malignant pain use analgesic and psychotropic medications. IMPLICATIONS: These findings provide the basis for further investigation into the level and appropriateness of analgesic and psychotropic medication use by older people with chronic pain. 相似文献