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1.
Infantile neuronal ceroid-lipofuscinosis (CLN1) is the form of neuronal ceroid-lipofuscinoses (NCL) with the earliest onset of symptoms. The locus of the most common form of these disorders, juvenile NCL (CLN3), has been mapped to chromosome 16. We report here linkage data of the same region in Finnish CLN1 families. Our results indicate that CLN1 is not allelic with CLN3 but represents a different locus, which is not located within about 70 cM in chromosome 16.  相似文献   
2.
We have examined the phylogenetic distribution of two t-specific markers among representatives of various taxa belonging to the genus Mus. The centromeric TCP-1a marker (a testicular protein variant specific for all t-haplotypes so far studied) has also been apparently detected in several non-t representatives of the Mus IVA, Mus IVB, and probably M. cervicolor species. By contrast, a t-specific restriction- fragment-length polymorphism allele (RFLP) of the telomeric alpha- globin pseudogene DNA marker alpha-psi-4 was found only in animals belonging to the M. musculus-complex species either bearing genuine t- haplotypes or, like the M. m. bactrianus specimen studied here, likely to do so. This t-specific alpha-psi-4 RFLP allele was found to be as divergent from the RFLP alleles of the latter, non-t, taxonomical groups as it is from Mus 4A, Mus 4B, or M. spretus ones. These results suggest the presence of t-haplotypes and of t-specific markers in populations other than those belonging to the M. m. domesticus and M. m. musculus subspecies, implying a possible origin for t-haplotypes prior to the radiation of the most recent offshoot of the Mus genus (i.e., the spretus/domesticus divergence), some 1-3 Myr ago.   相似文献   
3.
Total DNAs from twelve natural isolates of Escherichia coli from animals and humans were examined by hybridization with a probe for IS1. Considerable variation in copy number was found. In the case of two strains isolated from the same individual, one strain contained no copies of IS1 and the other, much greater than 30. Evidence was also obtained for the existence of IS1-like elements (iso-IS1s) of greater than 15% sequence divergence relative to the IS1 from antibiotic resistance plasmid R100.  相似文献   
4.
Brita  Nyman 《Physiologia plantarum》1969,22(4):809-818
Biotin can not replace nonanal for Dipodascus aggregatus. The growth-promoting effect of nonanal (80 μW) remained unchanged when the concentration of biotin was increased from 2 μm per 1 to 200 μm per I. Oleic acid stimulated the growth of D. aggregates. However, unlike nonanal, oleic acid promoted growth even if cells from the exponential phase of growth were used as inoculum. The concentrations of oleic acid required to produce growth–stimulation were considerably higher than the concentrations of nonanal required to promote growth. The growth-stimulating effect f nonanal seems to be different from t he effect of oleic acid. The incorporation of 1C-ghtCOM by D. aggregates was stimulated by the addition of nonanal (80μm) to the growth medium. The uptake of glucosamine was not affected by nonanal (80 or 160 μM in the presence of ethanol, 0.8 to 100μ in the absence of ethanol). Hexokinase activity in cell-free homogenates was not affected by the addition of nonanal over a concentration range from 0.0059 to 1250μM.  相似文献   
5.
Nyman B 《Physiologia plantarum》1969,22(6):1322-1328
The growth of Dipodascus aggregatus in cultures inoculated with cells from the acceleration phase of growth was stimulated by the saturated and unbranched aliphatic C(3) C(4) , and C(6) to C(11) aldehydes (80 μM]. Nonanal was most active in stimulating growth. The C(12) aldehyde inhibited growth. The C(5) , aldehyde generally inhibited growth. - Nonan did not affect growth. 2-Nonanone and 5-nonanone promoted growth insignificantly. - In cultures inoculated with cells from the exponential phase growth was unaffected or even inhibited by all the aldehydes tested. The C(4) , C(5) , C(10) , and C(11) aldehydes inhibited growth to a larger extent than nonanal.  相似文献   
6.
Restriction endonuclease mapping of previously constructed dut plasmids has been carried out using the enzymes PvuI, PvuII and SacI. Various dut plasmids were also tested in the "maxicell" protein-synthesizing system. They all show two protein bands in common, one of Mr 16000 in agreement with the size previously reported for the purified dUTPase subunit (Shlomai and Kornberg, 1978). With the information obtained the structural gene for dUTPase can be assigned to a 950-bp SacI-PvuII fragment of the E. coli genome. Studies, described in the preceding paper, on the overproduction of dUTPase by bacterial strains carrying different dut plasmids strongly suggest that the dut gene is transcribed in the direction from the SacI site towards the PvuII site and that the SacI site is located within the dut control region. The second protein band observed in the "maxicell" experiments has an Mr of 23500. Its identity is unknown but it may represent a precursor of dUTPase or the product of a separate gene located between dut and pyrE.  相似文献   
7.
The primary structure of the coat protein subunit in satellite tobacco necrosis virus has been investigated. The results obtained are consistent with and support the proposal for the amino acid sequence made from the nucleotide sequence of RNA (Ysebaert et al., 1980). This would imply that no intervening sequences of RNA occur in the cistron for the satellite tobacco necrosis virus coat protein. The polypeptide chain of the protein consists of 195 amino acid residues. It contains one sulfhydryl group but no disulfide bridges. The distribution of various kinds of amino acid residues along the chain is markedly uneven.  相似文献   
8.
Macrophages are essential for the development of innate immune responses against a variety of infectious factors. They detect invading pathogens via their pattern recognition receptors such as toll-like receptors (TLRs). TLR7/8 recognizes ssRNA from various viruses. In the present study, we have used 2-DE gel-based proteomics to find novel TLR7/8 target proteins in human monocyte-derived macrophages in order to improve our understanding of the virus recognition by this TLR. A total of 27 protein spots were found to be reproducibly differentially expressed between control and TLR7/8 activated 2-DE gel pairs, 18 spots being more than two-fold upregulated and nine spots being at least two-fold downregulated. Several proteins involved in defense against toxic superoxide (O2-) and other reactive oxygen species, such as manganese-containing superoxide dismutase (SOD2), glutathione peroxidase, and peroxiredoxins 1 and 6 were highly upregulated after TLR7/8 activation. Western blot analysis showed that activation of macrophages with TLR2, TLR3, TLR4, and TLR7/8 ligands also strongly upregulated SOD2 protein expression. In conclusion, our results show that the activation of pattern recognition receptors of the innate immune system results in strong upregulation of SOD2 gene expression suggesting that SOD2 protects macrophages from oxidative stress during microbial infection.  相似文献   
9.
Inverted organic solar cells generally exhibit a strong s‐shaped kink in the current–voltage characteristics (JV curve) that may be removed by exposure to UV light (light‐soaking) leading to a drastically improved performance. Using in‐device characterization methods the origin of the light‐soaking issue in inverted solar cells employing titanium dioxide (TiO2) as an electron selective layer is clarified. An injected hole reservoir accumulated at the TiO2/organic interface of the pristine device is observed from extraction current transients; the hole reservoir increases the recombination and results in an s‐shape in the JV curve of pristine devices. The hole reservoir and the s‐shape is a result of the energetics at the selective contact in the pristine device; the effect of UV exposure is to decrease the work function of the indium tin oxide/TiO2‐contact, increasing the built‐in potential. This hinders the build‐up of the hole reservoir and the s‐shape is removed. The proposed model is in excellent agreement with drift‐diffusion simulations.  相似文献   
10.
Interleukin-4 (IL-4) is the main cytokine that polarizes activated na?ve CD4+ T cells in the T helper 2 (Th2) direction. IL-4 also regulates the subsequent stages of Th2 cell-mediated diseases, such as allergies. We conducted a proteomics study to identify IL-4-induced differences during the initial stages of T helper cell differentiation. Primary CD4+ T lymphocytes were isolated from human cord blood, activated through CD3 and CD28, and cultured in the presence or absence of IL-4. Soluble proteins were separated by two-dimensional electrophoresis and visualized by staining with autoradiography, which indicated that at least 20 proteins might be regulated by IL-4. From this minimum of 20 stained proteins, altogether 35 proteins were identified using tandem mass spectrometry. Interestingly the fragmented form of GDP dissociation inhibitor expressed in lymphocytes/Rho GDP dissociation inhibitor 2 (Ly-GDI), a known target of Caspase-3, was observed to be down-regulated in IL-4-treated cells. It was shown in further studies that IL-4 decreases Caspase-3 activity and cell death in these cells. Neutralizing Fas-Fas ligand interaction led to decreased Caspase-3 activity and lowered Ly-GDI fragmentation. We further characterized the effects of IL-4 on the expression of main regulators in the Fas-mediated pathway. We demonstrated that IL-4 decreases expression of Fas receptor and increases expression of Bid, Bcl-2, and Bcl-xL. Importantly IL-4 significantly up-regulated the short form of c-FLIP, although the levels of c-FLIP long were unaltered after IL-4 induction. Taken together, our results indicate that IL-4 inhibits caspase activity during the initial stages of human Th2 cell differentiation by regulating expression of several key players in the Fas-induced pathway.  相似文献   
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