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31.
Tam S. David-West 《Archives of virology》1975,48(1):21-28
Concurrent and consecutive infection and immunisation with yellow fever virus and UGMP-359 virus was investigated in mice, using identical doses of both viruses. In double infection it was shown that both viruses could multiply independently of one another, when both were inoculated simultaneously by the intracerebral route. On the other hand, there was mutual exclusion between them when the inoculation of one antedated the other, by the same intracerebral route. Both viruses multiplied to similar titres, in single infection, in the target organ (brain). By the intraperitoneal route, the outcome was influenced byhe relative sensitivity of this route of inoculation to support and sustain the replication of either virus. Thus, because yellow fever virus replicated more than UGMP-359 after intraperitoneal inoculation, the latter is always excluded, even when the inoculation ofUGMP-359 preceded that of yellow fever. In the double immunization studies it was shown that comparative specific antibody titres to both viruses were obtained either when both viruses, as immunogens, were given simultaneously, or when the inoculation of one was alternated, at weekly intervals, with the other. 相似文献
32.
33.
The UTX gene escapes X inactivation in mice and humans 总被引:7,自引:3,他引:7
Greenfield A; Carrel L; Pennisi D; Philippe C; Quaderi N; Siggers P; Steiner K; Tam PP; Monaco AP; Willard HF; Koopman P 《Human molecular genetics》1998,7(4):737-742
We recently have identified a ubiquitously transcribed mouse Y chromosome
gene, Uty , which encodes a tetratricopeptide repeat (TPR) protein. A
peptide derived from the UTY protein confers H-Y antigenicity on male
cells. Here we report the characterization of a widely transcribed X-linked
homologue of Uty , called Utx , which maps to the proximal region of the
mouse X chromosome and which detects a human X-linked homologue at Xp11.2.
Given that Uty is ubiquitously transcribed, we assayed for Utx expression
from the inactive X chromosome (Xi) in mice and found that Utx escapes X
chromosome inactivation. Only Smcx and the pseudoautosomal Sts gene on the
mouse X chromosome have been reported previously to escape inactivation.
The human UTX gene was also found to be expressed from Xi. We discuss the
significance of these data for our understanding of dosage compensation of
X-Y homologous genes in humans and mice.
相似文献
34.
Mahadevan MM; McIntosh Q; Miller MM; Breckinridge SM; Maris M; Moutos DM 《Human reproduction (Oxford, England)》1998,13(4):979-982
Cryopreservation of human zygotes and embryos has been routinely performed
by in-vitro fertilization clinics for many years. Karran and Legge (1996)
first reported that formaldehyde (FA) present in the cryoprotective
solutions can have a deleterious effect on mouse oocytes. FA is a
cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse
zygotes was investigated. In addition, the concentrations of FA in
propanediol (PROH) obtained from various sources were determined. Pooled
1-cell embryos were dispensed into droplets of modified Ham's F10 or human
tubal fluid containing various concentrations of FA. Since bovine serum
albumin (BSA) may minimize toxicity additional trials were done as above in
the absence of BSA. FA concentration in the standard 1.5 M PROH, from
different sources in water, was measured in the same assay using a standard
curve of 0-100 microM FA. FA in a complex medium had a significant
deleterious effect on embryo development and hatching but only at 1 mM
concentration (P < 0.000001; see Tables I-III). There was no significant
effect of FA at 100 microM. However, in a simple medium even 50 microM FA
decreased embryo hatching. FA was present in 1.5 M PROH from different
sources (range 1.0-35.3 microM concentration). It appears that FA
concentrations do not increase with storage because FA concentrations were
low even after opening and storage for 3 years on the shelf. This suggests
that FA is a contaminant during the manufacturing process and may vary from
manufacturer to manufacturer and batch to batch. Until further studies are
done to confirm the lack of toxicity to embryos during cryopreservation
(with or without FA scavengers) it may be prudent to screen all batches of
cryoprotectants for FA as part of quality control.
相似文献
35.
A paramyxovirus SV5 mutant (rSV5-P/V-CPI-) that encodes 6 naturally-occurring P/V gene substitutions is a potent inducer of type I interferon (IFN) and is restricted for low moi growth, two phenotypes not seen with WT SV5. In this study, we have compared the IFN sensitivity of WT SV5 and the rSV5-P/V-CPI- mutant in tumor cell lines and in cultures of normal primary cells. We have tested the hypothesis that differences in IFN induction elicited by WT rSV5 and rSV5-P/V-CPI- are responsible for differences in low moi growth and spread. In contrast to WT SV5, low moi infection of A549 lung carcinoma cells with rSV5-P/V-CPI- resulted in a plateau of virus production by 24-48 h pi when secreted IFN levels were between approximately 100 and 1000 U/ml. Gene microarray and RT-PCR analyses identified IFN genes and IFN-stimulated genes whose expression were increased by infection of A549 cells with WT and P/V mutant viruses. Restricted low moi growth and spread of rSV5-P/V-CPI- in A549 cells was relieved in the presence of neutralizing antibodies to IFN-beta but not TNF-alpha. When A549 or MDA-MB-435 breast tumor cells were pretreated with IFN, both WT and P/V mutant viruses showed delayed spread and approximately 10-fold reduction in virus yield, but infections were not eliminated. Using normal primary human epithelial cells that have undergone limited passage in culture, WT rSV5 and rSV5-P/V-CPI- displayed high moi growth properties that were similar to that seen in A549 cells. However, IFN pretreatment of these primary cells as well as normal human lung cells eliminated low moi spread of both mutant and WT rSV5 infections. Together, these data demonstrate that SV5 growth in normal primary human cells is highly sensitive to IFN compared to growth in some tumor cell lines, regardless of whether the P/V gene is WT or mutant. These results suggest a model in which spread of WT SV5 in normal human cells is dependent on the ability of the virus to prevent IFN synthesis. The implications of these results for the use of recombinant paramyxoviruses as vectors are discussed. 相似文献
36.
Tam S. David-West B. O. Osunkoya 《International journal of experimental pathology》1973,54(3):274-282
Antilymphocytic serum (ALS) raised in white New Zealand rabbits with Swiss albino mice thymocytes significantly protected mice challenged with Congo virus (Crimean haemorrhagic fever virus related) from the lethal episodes of the infection. There was a delaying as well as a sparing effect on morbidity and mortality, which was particularly striking in adult mice. Histopathological examination of brain sections of treated mice showed a complete suppression of the characteristic inflammatory tissue reactions, which marked similar sections prepared from mice treated with normal rabbit serum (NRS) or from the virus control group. Unlike Congo virus infection, ALS did not have a demonstrable effect on Mokola virus (rabies virus related) infection. A comparison of the effect of ALS on Congo virus infection and its effect on murine lymphocytic choriomeningitis is made.It was observed that a constant feature of ALS treatment was gross splenic enlargement in the animals. It is suggested that this might have been due, at least in part, to a gross sequestration of sensitized red blood cells, as revealed by the histopathology of the organ. Other possible causes of splenomegaly in immunosuppressed mice are also discussed. 相似文献
37.
38.
Summary The development of vesicular stomatitis virus in chick embryo fibroblasts has been studied. Infectivity titres were correlated with electron microscopic observations. The demonstration of virus particles in both ultrathin sections of infected cells and in the culture fluid coincided with a rise in virus titre. Intracytoplasmic crystalline arrays, presumably progeny virus materials, were demonstrated in infected but not in noninfected cells. The individual units of the crystals measure about 61-61 m. across. Virus matures both at the cell surface and at vacuolar membranes in finger-like projections. The typical mature virus particle is essentially bullet-shaped, with average dimensions of 176×71 m. While virus synthesis seems to occur exclusively in the cytoplasm with probably no participation of the cell nucleus, free virus particles were not observed in the cytoplasm. Evidence for a close similarity between the morphology and the development of vesicular stomatitis virus and rabies virus are given. It is suggested that both these viruses and other similar animal viruses showing the characteristic structural polarity may be taxonomically related.A visiting scientist from the Nigerian Federal Government. 相似文献
39.
AIMS: To investigate the serum creatine kinase isoenzyme pattern, specific biochemical markers of bone metabolism, and cytokines in a Chinese family with osteopetrosis, and correlate abnormalities with the pathophysiology of this condition. METHODS: A Chinese female baby was diagnosed with malignant infantile osteopetrosis at the age of 3 weeks by clinical history and biochemical investigations. We studied the laboratory and radiological manifestations of this index case and her family members. RESULTS: Serum CK-BB fraction of our index patient was elevated to 18.0% (normal 1.6-7.6%). Her biochemical markers of bone resorption including serum C-terminal telopeptide concentration and urine N-terminal telopeptide to creatinine ratio were decreased to 0.54 microg/L (normal 0.72-1.56 microg/L) and 159 x 10(-6) (normal 372-900 x 10(-6)), respectively. Serum cytokines including soluble receptor activator of nuclear factor kappa-B ligand (sRANKL) concentration was suppressed to 0.11 pmol/L (normal 0.23-0.82 pmol/L) and osteoprotegerin (OPG) concentration was 4.9 pmol/L (normal 2.8-4.9 pmol/L), resulting in an elevated OPG to sRANKL ratio of 44.5 (normal 3.8-19.4) in favour of bone formation. CONCLUSIONS: If left untreated, this condition is usually fatal within the first year of life. With early diagnosis, management including bone marrow transplantation can be planned ahead and will result in a better survival. 相似文献
40.