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271.
Terada N Ohno N Yamakawa H Ohara O Liao X Baba T Ohno S 《Histochemistry and cell biology》2005,124(3-4):303-311
Protein 4.1 families have recently been established as potential organizers of an adherens system. In the adult mouse testis,
protein 4.1G (4.1G) localized as a line pattern in both basal and adluminal compartments of the seminiferous tubules, attaching
regions of germ cells and Sertoli cells. By double staining for 4.1G and F-actin, their localizations were shown to be different,
indicating that 4.1G was localized in a region other than the basal and apical ectoplasmic specializations, which formed the
Sertoli–Sertoli cell junction and Sertoli–spermatid junction, respectively. By electron microscopy, immunoreactive products
were seen exclusively on the cell membranes of Sertoli cells, attaching to the various differentiating germ cells. The immunolocalization
of cadherin was identical to that of 4.1G, supporting the idea that 4.1G may be functionally interconnected with adhesion
molecules. In an experimental mouse model of cadmium treatment, in which tight and adherens junctions of seminiferous tubules
were disrupted, the 4.1G immunostaining in the seminiferous tubules was dramatically decreased. These results indicate that
4.1G may have a basic adhesive function between Sertoli cells and germ cells from the side of Sertoli cells. 相似文献
272.
Protein 4.1 G localizes in rodent microglia 总被引:2,自引:2,他引:0
Ohno N Terada N Tanaka J Yokoyama A Yamakawa H Fujii Y Baba T Ohara O Ohno S 《Histochemistry and cell biology》2005,124(6):477-486
Although it was reported that protein 4.1 G, a cytoskeletal protein characterized by its general expression in the body, interacts
with some signal transduction molecules in the central nervous system (CNS), its distribution and significance in vivo remained
to be elucidated. In the present study, we have identified 4.1 G-positive cells in the rodent CNS, and demonstrated its immunolocalization
in the developing mouse CNS. In the rodent CNS, 4.1 G was colocalized with markers for microglia, such as CD45, OX-42 and
ionized calcium-binding adapter molecule 1 (Iba1), but not with markers for neuronal or other glial cells. Additionally, colocalization
of 4.1 G and A1 adenosine receptor was observed in the mouse cerebrum. In a mixed glial culture, most OX-42-positive microglia
were positive for 4.1 G, and 4.1 G isoforms of the same molecular weight as in the rat brain were expressed in cultured microglia,
where 4.1 G mRNA was detected by RT-PCR. In the developing mouse cerebral cortex, 4.1 G was detected in immature microglia,
which were positive for Iba1. These results indicate that 4.1 G in the CNS is mainly distributed in microglia in vivo. Considering
the interactions between 4.1 G and the signal transduction molecules, putative roles have been propsed for 4.1 G in microglial
functions in the CNS. 相似文献
273.
Morii Y Matsuda H Ohara K Hashimoto M Miyairi K Okuno T 《Bioorganic & medicinal chemistry》2005,13(17):5113-5144
Glycosylation reactions of 5-thioglucopyranosyl trichloroacetimidates bearing ethereal protective groups at the 2-O-position 14-15, and 37 proceed smoothly to give alpha-glycosides stereoselectively by using a catalytic amount of silyl triflate. This methodology allowed us to achieve syntheses of sulfur-substituted isomaltotetraoside 2 and maltotetraoside 3. These studies also revealed that benzoyl-protected 5-thioglucopyranosyl trichloroacetimidate 12 underwent beta-selective glycosylation with C6-OH glucopyranosyl acceptors upon activation by BF3OEt2. This was applied for preparation of sulfur-substituted gentiobiosides 1 and 46. 相似文献
274.
Kashiwada Y Aoshima A Ikeshiro Y Chen YP Furukawa H Itoigawa M Fujioka T Mihashi K Cosentino LM Morris-Natschke SL Lee KH 《Bioorganic & medicinal chemistry》2005,13(2):443-448
(+)-1(R)-Coclaurine (1) and (-)-1(S)-norcoclaurine (3), together with quercetin 3-O-beta-D-glucuronide (4), were isolated from the leaves of Nelumbo nucifera (Nymphaceae), and identified as anti-HIV principles. Compounds 1 and 3 demonstrated potent anti-HIV activity with EC50 values of 0.8 and <0.8 microg/mL, respectively, and therapeutic index (TI) values of >125 and >25, respectively. Compound 4 was less potent (EC50 2 microg/mL). In a structure-activity relationship study, other benzylisoquinoline, aporphine, and bisbenzylisoquinoline alkaloids, including liensinine (14), negferine (15), and isoliensinine (16), which were previously isolated from the leaves and embryo of Nelumbo nucifera, were evaluated for anti-HIV activity. Compounds 14-16 showed potent anti-HIV activities with EC50 values of <0.8 microg/mL and TI values of >9.9, >8.6, and >6.5, respectively. Nuciferine (12), an aporphine alkaloid, had an EC50 value of 0.8 microg/mL and TI of 36. In addition, synthetic coclaurine analogs were also evaluated. Compounds 1, 3, 12, and 14-16 can serve as new leads for further development of anti-AIDS agents. 相似文献
275.
Hegab AE Sakamoto T Saitoh W Nomura A Ishii Y Morishima Y Iizuka T Kiwamoto T Matsuno Y Massoud HH Massoud HM Hassanein KM Sekizawa K 《Biochemical and biophysical research communications》2005,329(4):1246-1252
It is recognized that genetic factors play a role in the susceptibility to COPD. COPD is characterized by airflow limitation. Chronic inflammation causes small airway disease and parenchymal destruction, leading to the airflow limitation. Polymorphisms in pro-inflammatory cytokine genes may confer a risk for the development of COPD. A case-control association study was performed in Japanese population (88 COPD patients and 61 controls) and Egyptian population (106 patients and 72 controls). Genotype and allele frequencies of the TNFalpha -308 G/A and +489 G/A polymorphisms, the IL1beta -511 C/T, -31 T/C, and +3954 C/T polymorphisms, and a VNTR polymorphism in intron 2 of the IL1RN gene were investigated. In addition, pairwise haplotype frequencies were analyzed. When studied independently, none of the polymorphisms were associated with the development of COPD in both populations. However, in the Egyptian population, the distributions of the haplotype (IL1beta -31 T/C : IL1beta +3954 C/T) were significantly different between the COPD patients and the controls (p(corr)=0.0037). Our findings suggest that this haplotype within the IL1beta gene may be involved in the pathogenesis of COPD and that the genetic factors of COPD susceptibility might be different between different populations. 相似文献
276.
Hiratani K Haruta T Tani A Kawahara J Usui I Kobayashi M 《Biochemical and biophysical research communications》2005,335(3):836-842
In 3T3-L1 adipocytes, insulin or anisomycin stimulated phosphorylation of IRS-1 at Ser(307) and Ser(636/639), both of which were partially reduced by the mTOR inhibitor, rapamycin, or the JNK inhibitor, SP600125, and were further inhibited by a combination of them. Interestingly, anisomycin-induced p70(S6K) phosphorylation was reduced by SP600125, while insulin-induced p70(S6K) phosphorylation was not. Furthermore, unlike insulin, anisomycin failed to elicit translocation or degradation of IRS-1. These results indicate that mTOR and JNK play roles in phosphorylating IRS-1 serine residues, and that insulin and anisomycin are different in terms of the relationship of activation between mTOR and JNK, and the effects on IRS-1 localization and stability. 相似文献
277.
278.
279.
Inheritance of 9 microsatellite loci was examined in 3 families of gynogenetic Pacific abalone Haliotis discus hannai produced by fertilizing eggs with UV-irradiated sperm followed by inhibition of the second meiotic division. The proportion
of heterozygous progeny was used to estimate marker-centromere (M-C) distances. All loci conformed to Mendelian segregation
in the control crosses when null alleles were accounted for. The absence of paternal alleles confirmed the gynogenetic origin
of the offspring and indicated 100% success for 3 families. Estimated recombinant frequencies ranged from 0.10 to 0.60, which
is lower than those observed in other gynogenetic diploid animals. The mean recombination frequency was 0.22, corresponding
to a fixation index of 0.78 in one generation. This is 3.12 times the increase in homozygosity expected after one generation
of sib mating (0.25), suggesting meiotic gynogenesis may be an effective means of rapid inbreeding in the abalone. M-C map
distances for the 9 loci varied between 5 and 30 cM under the assumption of complete interference. The information about M-C
distances will be useful for future gene mapping in H. discus hannai. 相似文献
280.
Tsutsumi H Katagi M Miki A Shima N Kamata T Nishikawa M Nakajima K Tsuchihashi H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,819(2):315-322
To prove the intake of recently controlled designer drugs, N-benzylpiperazine (BZP) and 1-(3-trifluoromethylphenyl)piperazine (TFMPP), a simple, sensitive and reliable method which allows us to simultaneously detect BZP, TFMPP and their major metabolite in human urine has been established by coupling gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS). GC-MS accompanied by trifluoroacetyl (TFA) derivatization and LC-MS analyses were performed after the enzymatic hydrolysis and the solid phase extraction with OASIS HLB, and BZP, TFMPP and their major metabolites, 4'-hydroxy-BZP (p-OH-BZP), 3'-hydroxy-BZP (m-OH-BZP) and 4'-hydroxy-TFMPP (p-OH-TFMPP), have found to be satisfactorily separated on a semi-micro SCX column with acetonitrile-40 mM ammonium acetate buffer (pH 4) (75:25, v/v) as the eluent. The detection limits produced by GC-MS were estimated to be from 50 ng/ml to 1 microg/ml in the scan mode, and from 200 to 500 ng/ml in the selected ion monitoring (SIM) mode. Upon applying the LC-ESI-MS technique, the linear calibration curves were obtained by using the SIM mode for all analytes in the concentration range from 10 ng/ml to 10 microg/ml. The detection limits ranged from 5 to 40 ng/ml in the scan mode, and from 0.2 to 1 ng/ml in the SIM mode. These results indicate the high reliability and sensitivity of the present procedure, and this procedure will be applicable for proof of intake of BZP and TFMPP in forensic toxicology. 相似文献