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31.
The immunomodulating effects of preoperative sizofiran (SPG) administration on regional lymph nodes were studied in patients
with stage III or IV head and neck cancer, by comparing the immunofunction of peripheral blood. The regional lymph nodes were
dissected surgically, and freshly obtained mononuclear cells were studied to investigate the interleukin-2 (IL-2) production,
the LAK and NK activities, and the quantitative analysis of the surface phenotype of the mononuclear cells. The results indicated
that SPG enhanced immunological activities in the regional lymph nodes, as shown by increased IL-2 production and cytotoxic
activities of the effector cells (NK, LAK), and increased helper T lymphocytes (CD4+) in the tumor-uninvolved lymph nodes. The immunofunction following SPG administration was attenuated, but was still augmented
in the regional lymph nodes with metastases. Therefore, SPG was found to be a biologic response modifier to enhance the immunofunctions
of the regional lymph node in patients with head and neck cancer. 相似文献
32.
The antitumor effect of the combined administration with recombinant human interleukin-2 (rIL-2) and sizofiran (SPG), a single
glucan of Shizophyllum commune Fries, was studied in vivo in C57BL/6 mice intraperitoneally inoculated with EL-4 lymphoma.
The effect was evaluated by a) comparing the survival time of the mice, b) analysis of the intraperitoneal cell population
in Giemsa-stained specimens, c) surface marker analysis of peritoneal exudative cells with flow cytometry, d) cytotoxic assay
of cells against EL-4 and Yac-1 lymphoma, and e) elimination of some cell populations by monoclonal antibodies, to identify
the antitumor-effector cells showing cytotoxic activity. The survival of mice given both rIL-2 and SPG was significantly longer
than the control mice or those given SPG alone or rIL-2 alone. It was demonstrated that the administration of SPG and/or rIL-2
to the EL-4 lymphoma-bearing mice activated immune-response cells in the peritoneal cavity such as T lymphocytes, NK cells,
or macrophages, which might be effective in reducing lymphoma cells. The combination of rIL-2 and SPG administration appears
to activate the antitumor- immune response at the tumor site more effectively than when either agent was administered alone. 相似文献
33.
Tohru Tsukui Sanae Miyake Sadahiro Azuma Hirotake Ichise Izumu Saito Yutaka Toyoda 《Molecular reproduction and development》1995,42(3):291-297
Replication-defective recombinant adenovirus, Adex4SRLacZL, was used as a vector for transferring exogenous genes in mouse zona pellucida-free eggs at the pronuclear stage. The vector contained the E. coli LacZ reporter gene under the control of the SRα promoter (SV40 early promoter-fused HTLV-I LTR), and the expression of the reporter gene was examined during preimplantation development in culture. Histochemical staining of the embryos for β-galactosidase activity showed that the exogenous LacZ gene as expressed in 98% of the embryos at the morula-blastocyst stages. As in the microinjection method, the exogenous genes could be pursued from the 2-cell stage. Neither apparent morphological changes nor cytotoxic effects were observed. Both the percentages of embryos expressing reporter genes and the rate of development to the blastocyst stage were higher in the adenovirus vector-treated embryos than in the microinjected ones. These results suggest that the adenovirus vector system is a useful tool in investigating the genetic control of early mammalian development. © 1995 wiley-Liss, Inc. 相似文献
34.
Obokata Junichi; Mikami Kohki; Yamamoto Yoshiharu; Hayashida Nobuaki 《Plant & cell physiology》1994,35(2):203-209
Microheterogeneity of a photosystem I (PSI) subunit encodedby a nuclear gene psaE was examined in Nicotiana sylvestris,with the aid of cDNA cloning, peptide mapping analysis and proteinsequencing. The psaE product of this plant has four isoformswhose mobilities in PAGE are slightly different from each other.We isolated two types of psaE cDNAs from a N. sylvestris cDNAlibrary, and designated the corresponding genes as psaEa andpsaEb, respectively. The psaEa and psaEb genes are 77% homologousat DNA level, and their translation products share 80.4% homologyfor the precursor proteins and 89.1% for the mature forms. Comparativeanalysis of the four isoproteins and the putative products ofthe two psaE genes revealed that two isoproteins out of fourare derived from psaEa gene, and the difference between thesetwo isoproteins lies in the respective presence or absence ofN-terminal alanine. Likewise, the other two proteins are derivedfrom psaEb with similar N-terminal heterogeneity. These resultsindicate that multi-gene organization and heterogeneous N-terminalformation at post-translational level are two possible causesfor PSI subunit polymorphism in isogenic plant lines. (Received October 8, 1993; Accepted November 30, 1993) 相似文献
35.
Junichi Mano Kunio Kawamoto G. Charles Dismukes Kozi Asada 《Photosynthesis research》1993,38(3):433-440
A new binding site for anions which inhibit the water oxidizing complex (WOC) of Photosystem II in spinach has been identified. Anions which bind to this site inhibit the flash-induced S2/S0 catalase reaction (2H2O22H2O+O2) of the WOC by displacing hydrogen peroxide. Using a mass spectrometer and gas permeable membrane to detect the 32O2 product, the yield and lifetime of the active state of the flash-induced catalase (to be referred to simply as flash-catalase) reaction were measured after forming the S2 or S0-states by a short flash. The increase in flash-catalase activity with H2O2 concentration exhibits a Km=10–20 mM, and originates from an increase in the lifetime by 20-fold of the active state. The increased lifetime in the presence of peroxide is ascribed to formation of the long-lived S0-state at the expense of the unstable S2-state. The anion inhibition site differs from the chloride site involved in stimulating the photolytic water oxidation reaction (2H2OO2+4e-+4H+). Whereas water oxidation requires Cl- and is inhibited with increasing effectiveness by F-CN-N3
-, the flash-catalase reaction is weakly inhibited by Cl-, and with increasing effectiveness by F-CN-, N3
-. Unlike water oxidation, chloride is unable to suppress or reverse inhibition of the flash-catalase reaction caused by these anions. The inhibitor effectiveness correlates with the pKa of the conjugate acid, suggesting that the protonated species may be the active inhibitor. The reduced activity arises from a shortening of the lifetime of the flash-induced catalase active state by 3–10 fold owing to stronger anion binding in the flash-induced states, S2 and S0, than in the dark S-states, S1 and S-1. To account for the paradoxical result that higher anion concentrations are required to inhibit at lower H2O2 concentrations, where S2 forms initially after the flash, than at higher H2O2 concentrations, where S0 forms initially after the flash, stronger anion binding to the S0-state than to the S2-state is proposed. A kinetic model is given which accounts for these equilibria with anions and H2O2. The rate constant for the formation/release of O2 by reduction of S2 in the WOC is <0.4 s-1.Abbreviations ADRY
acceleration of the deactivation reactions of the water splitting enzyme system Y
- BTP
bis [tris(hydroxymethyl)methylamino]-propane
- CCCP
carbonylcyanide m-chlorophenylhyrazone
- DCBQ
2,5-dichlorobenzoquinone
- DMBQ
2,3-dimethylbenzoquinone
- WOC
water oxidizing complex 相似文献
36.
Serum-free culture of rat keratinocytes 总被引:2,自引:0,他引:2
Hirosuke Oku Chikara Kumamoto Tomoyuki Miyagi Takanori Hiyane Junichi Nagata Isao Chinen 《In vitro cellular & developmental biology. Animal》1994,30(8):496-503
Summary Procedures for the serum-free culture of rat keratinocytes have been established. Basal cells prepared from epidermis of newborn
rat were stored in liquid nitrogen and used for primary culture. Among the available media, MCDB 153, developed originally
for human keratinocyte (HK) culture, was the best for the development of serum-free formulation. To grow rat keratinocytes,
bovine serum albumin was arbitrarily substituted for the macromolecule supplements needed for HK culture, i.e. fetal bovine
serum protein or bovine pituitary extract. Qualitative and quantitative adjustment of supplements was thereafter made to support
rapid cell growth. Satisfactory cell growth was achieved in the optimized medium of MCDB 153 supplemented with growth factors
and amino acids: insulin (10 μg/ml), hydrocortisone (0.1 μg/ml), epidermal growth factor (25 ng/ml), calcium chloride (0.2
mM), histidine (0.23 mM), isoleucine (0.05 mM), tryptophane (0.015 mM), threonine (1.25 mM), tyrosine (0.031 mM), alanine (4.08 mM), and albumin (2 mg/ml). This optimized culture system was superior to the original HK culture condition for rapid growth
of rat keratinocytes. Under our condition, cells grew as a monolayer, becoming confluent, but without stratification, and
were passaged 2 to 3 times without any changes in morphology. The serum-free formulation allows us to control more accurately
the concentrations of biomolecules in the medium including lipids and hormones, and therefore will be suitable for the study
focusing on lipid metabolism or hormonal regulation of rat keratinocytes. 相似文献
37.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology and occupational physiology》1993,67(4):354-359
We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
38.
Subunits of the Schizosaccharomyces pombe RNA polymerase II: enzyme purification and structure of the subunit 3 gene. 总被引:1,自引:0,他引:1
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To improve our understanding of the structure and function of eukaryotic RNA polymerase II, we purified the enzyme from the fission yeast Schizosaccharomyces pombe. The highly purified RNA polymerase II contained more than eleven polypeptides. The sizes of the largest the second-, and the third-largest polypeptides as measured by SDS-polyacrylamide gel electrophoresis were about 210, 150, and 40 kilodaltons (kDa), respectively, and are similar to those of RPB1, 2, and 3 subunits of Saccharomyces cerevisiae RNA polymerase II. Using the degenerated primers designed after amino acid micro-sequencing of the 40 kDa third-largest polypeptide (subunit 3), we cloned the subunit 3 gene (rpb3) and determined its DNA sequence. Taken together with the sequence of parts of PCR-amplified cDNA, the predicted coding sequence of rpb3, interrupted by two introns, was found to encode a polypeptide of 297 amino acid residues in length with a molecular weight of 34 kDa. The S. pombe subunit 3 contains four structural domains conserved for the alpha-subunit family of RNA polymerase from both eukaryotes and prokaryotes. A putative leucine zipper motif was found to exist in the C-terminal proximal conserved region (domain D). Possible functions of the conserved domains are discussed. 相似文献
39.
Abstract A novel mycoplasmal species designated as Mycoplasma penetrans has recently been isolated from patients infected with human immunodeficiency virus. The 16S rRNA gene from this mycoplasma was cloned and its nucleotide sequence determined. This sequence was aligned with previously published homologous sequences from several mycoplasmas and with related Gram-positive bacteria and a phylogenetic tree was constructed. The results indicate that M. penetrans belongs to the evolutionary group Pneumoniae. 相似文献
40.
The nucleotide sequence of a 27830-bp DNA segment in the 79°81°.region of the Bacillus subtilis genome has been determined.This region contains 29 complete ORFs including the sspE gene,which encodes a small acid-soluble spore protein gamma and locateson the one side terminal of our assigned region. A homologysearch for the products deduced from the 29 ORFs revealed thatnine of them exhibit significant similarity to known proteins,e.g. proteins involved in an iron uptake system, a multidrugresistance protein, a chloramphenicol resistance protein, epoxidehydrolase, adenine glycosylase, and a glucose-1-dehydrogenasehomolog. 相似文献