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71.
Summary Studies were undertaken to test the susceptibility of individual T cell subpopulations to retroviral-mediated gene transduction. Gene transfer into human tumor-infiltrating lymphocytes (TIL) or peripheral blood mononuclear cells (PBMC) was carried out by transduction with an amphotropic murine retroviral vector (LNL6 or N2) containing the bacterialneo R gene. The presence of theneo R gene in the TIL population was demonstrated by Southern blot analysis, detection of the enzymatic activity of the gene product and by the ability of transduced TIL to proliferate in high concentrations of G418, a neomycin analog that is toxic to eukaryotic cells. The presence of theneo R gene in TIL did not alter their proliferation or interleukin-2 dependence compared to nontransduced TIL. The differential susceptibility of CD4+ and CD8+ lymphoid cells to the retro-virus-mediated gene transfer was then tested. Transduction of heterogeneous TIL cultures containing both CD4+ and CD8+ cells resulted in gene insertion into both T cell subsets with no preferential transduction frequency into either CD4+ or CD8+ cells. In other experiments highly purified CD4+ and CD8+ T cell subpopulations from either TIL or PBMC could be successfully transduced with theneo R gene as demonstrated by Southern blot analysis and detection of the gene product neophosphotransferase activity. No such activity or vector DNA could be detected in controls of nontransduced cells. In these highly purified cell subsets the distinctive T cell phenotypic markers were continually expressed after transduction, G418 selection and long-term growth. Clinical trials have begun in patients with advanced cancer using heterogeneous populations of CD4+ and CD8+ gene-modified TIL. Current address: Bone Marrow Transplantation, Hadassah University Hospital, 91120 Jerusalem, Israel  相似文献   
72.
Summary Paramyotonia congenita (PC), an autosomal dominant non-progressive muscle disorder, is characterised by cold-induced stiffness followed by muscle weakness. The weakness is caused by a dysfunction of the sodium channel in muscle fibre. Parts of the gene coding for the -subunit of the sodium channel of the adult human skeletal muscle (SCN4A) have been localised on chromosome 17. To investigate the role of this gene in the etiology of PC, a linkage analysis in 17 well-defined families was carried out. The results (z=20.61, =0.001) show that the mutant gene responsible for the disorder is indeed tightly linked to the SCN4A gene. The mutation causing hyperkalemic periodic paralysis (HyperPP) with myotonia has previously been mapped to this gene locus by the same candidate gene approach. Thus, our data suggest that PC and HyperPP are caused by allelic mutations at a single locus on chromosome 17.Dedicated to Professor P. E. Becker on the occasion of his 83rd birthday.  相似文献   
73.
Summary Two recent articles have reported the linkage of a gene for recessive spinal muscular atrophy (SMA) on the chromosome region 5q11.2–13.3. Our data show no linkage of the dominantly inherited forms of SMA to this chromosome region.  相似文献   
74.
After murine fetal cells from the rostral mesencephalic tegmentum were isolated, prepared, and cultured; neuronal and glial cells in primary mixed cell cultures were exposed to ferric nitrilotriacetate (Fe-NTA) at varying concentrations. Studies were performed at 23 days in culture after 14 day exposure to Fe-NTA. In addition to morphologic studies, biochemical assays including specific [3H]flunitrazepam (FLU) binding, clonazepam (CLO)-displaceable [3H]-FLU binding, Ro5-4864-displaceable [3H]-FLU binding, [3H]dopamine (DA) uptake, [3H]haloperidol (HAL) binding, [3H]spiperone (SP) binding, glutamine synthetase activity (GS), and protein determinations were performed. The data demonstrate that chelated ferric iron has an adverse effect on these cells. The data also demonstrate that increasing concentrations of Fe-NTA resulted in massive neuronal dropout leaving the culture population virtually all glial; however, the specific binding of [3H]HAL and [3H]SP increased. There was a concomitant decrease in both glutamine synthetase activity and overall protein content. The mechanism of enhancement in the presence of Fe-NTA of [3H]HAL and [3H]SP binding is unknown and may be unique, but may be related to the known increase in D2 receptor ligand affinity in the presence of other multivalent cations (Ca2+ and Mg2+).  相似文献   
75.
76.
The main polymorphic system of esterase isoenzymes in adults of the G3 laboratory strain ofAnopheles gambiae consists of two to five major bands of activity per individual. The bands are designated 5S, 5F, 13, 14, and 15. In genetic crosses, the genes which coded for the bands assorted as three codominant alleles, Est A, Est B, and Est C, at a single autosomal locus. Homozygotes for the Est C allele were significantly underrepresented among backcross progeny. The developmental pattern of esterase expression was examined. Esterase gene expression in embryos was first detectable between 2 and 12 hr after oviposition. The initiation or termination of expression of some of the bands corresponded to boundaries between developmental stages. Most of the esterase fractions were not specifically localized within the tissues tested, with the exception of a series of bands which were restricted largely to adult male testes.  相似文献   
77.
Vernonia galamensis is a good source of seed oil rich in epoxy acid, which can be used to manufacture plastic formulations, protective coatings, and other products. Seed from a natural stand in Ethiopia contained 31% epoxy acid. Under cultivation in Kenya, this unimproved germplasm produced a substantial yield of seed with 32% epoxy acid. This African species has good natural seed retention and is a promising new crop for semiarid tropical areas.  相似文献   
78.
The effects of the tubulin-binding drug colchicine on cultured neonate cardiac cell function were investigated. Application of low doses of colchicine (but not lumicolchicine) caused an early reversible increase in beating rate with a concomitant decrease in amplitude. Treatment of the cells with trypsin at a dose that removes surface tubulin but does not inhibit spontaneous beating, diminished the colchicine effect. Surface radio-iodination of the live cultures followed by two-dimensional gel electrophoresis and radioautography revealed that two spots were heavily labeled. These spots co-migrated with purified brain tubulin. Fibroblasts derived from the cardiac cultures did not label over the tubulin spots. Trypsin treatment removed the presumptive tubulin from the radioautographs but only removed the most basic portion of the alpha-tubulin spot from the stained gel. These results are consistent with a surface membrane role for an iso-form of tubulin in neonate cardiac cells.  相似文献   
79.
A bottle plate for the cultivation of methanogens or other organisms in a defined pressurized-gas atmosphere was developed. The bottle provides the convenience of an agar streak plate, solves the problem of the water exudate from agar medium, and provides a convenient way of adding or sampling a defined gas atmosphere.  相似文献   
80.
Pseudomonas putida B2 is able to grow on o-nitrophenol (ONP) as the sole source of carbon and nitrogen. ONP was converted by a nitrophenol oxygenase to nitrite and catechol. Catechol was then attacked by a catechol 1,2-dioxygenase and further degraded through an ortho-cleavage pathway. ONP derivatives which were para-substituted with a methyl-, chloro-, carboxy-, formyl- or nitro-group failed to support growth of strain B2. Relevant catabolic enzymes were characterized to analyze why these derivatives were not mineralized. Nitrophenol oxygenase of strain B2 is a soluble, NADPH-dependent enzyme that is stimulated by magnesium, manganese, and calcium ions. It is active toward ONP, 4-methyl-, 4-chloro-, and to a lesser extent, 4-formyl-ONP but not toward 4-carboxy- or 4-nitro-ONP. In addition, 4-formyl-, 4-carboxy-, and 4-nitro-ONP failed to induce the formation of nitrophenol oxygenase. Catechol 1,2-dioxygenase of strain B2 is active toward catechol and 4-methyl-catechol but only poorly active toward chlorinated catechols. 4-Methyl-catechol is likely to be degraded to methyl-lactones, which are often dead-end metabolites in bacteria. Thus, of the compounds tested, only unsubstituted ONP acts as an inducer and substrate for all of the enzymes of a productive catabolic pathway.  相似文献   
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