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1.
Cloning of cDNA encoding human H-protein, a constituent of the glycine cleavage system 总被引:1,自引:0,他引:1
K Hiraga S Kure M Yamamoto Y Ishiguro T Suzuki 《Biochemical and biophysical research communications》1988,151(2):758-762
A cDNA that encodes human H-protein, a constituent protein of the glycine cleavage system, was cloned with anti-rat H-protein antibody as a probe from a human liver cDNA library constructed with an expression vector, lambda gt11. The longest size of cDNA of the isolated clones was about 750 base long (lambda HH15B9). On the other hand, we determined the primary structure of human H-protein from the amino terminal Ser by the 12th Val, including a hexapeptide, -Glu-Lys-His-Glu-Trp-Val-. In addition to the finding that most cDNA inserts cloned hybridized with the synthetic DNA probe composed of the possible sequences for the hexapeptide, we confirmed that lambda HH15B9 encodes the partial primary structure of H-protein in an open reading frame. 相似文献
2.
3.
Mitsuru Iwata Shoko Iwata Mark A. Everett Bryan B. Fuller 《In vitro cellular & developmental biology. Plant》1990,26(6):554-560
Summary A human foreskin organ culture system has been developed to study the response of human skin to hormonal stimulation. Foreskins
are maintained in culture on floating plastic supports which allows the epidermal surface to be exposed to air while the dermis
is bathed in nutrient medium. Both black and white human foreskins can be maintained in organ culture for at least 1 wk with
no change in the tissue structure or cell viability as determined by histochemical staining and by dopa reaction staining.
Tyrosinase activity in both black and white human foreskin cultures decays markedly during the first 2 d of culture to a new
steady state level which remains stable throughout the culture period. Both black and white foreskin cultures consistently
demonstrate 2- to 10-fold increases in tyrosinase activity when treated with theophylline (1 mM). Approximately 90% of all skin cultures examined showed an increase in enzyme activity when treated with this phosphodiesterase
inhibitor. Dibutyryl cAMP (0.1 mM) and [Nle4, D-phe7]-alpha MSH (10−8
M), were also found to markedly stimulate tyrosinase activity in some skin cultures, whereas alpha-MSH and prostaglandin E1 produced only an inconsistent and small increase in the activity of the enzyme. Histamine (1 μM), vitamin D3 (1 μM), and retinoic acid (1μM) failed to stimulate tyrosinase activity in either white or black foreskin cultures. This hormone-responsive organ culture
system can be utilized to characterize the molecular processes responsible for the regulation of tyrosinase and pigmentation
in human skin.
This work was supported by a research contract from the Oklahoma Center for the Advancement of Science and Technology (OCAST)
and by a research grant from the Presbyterian Health Foundation. 相似文献
4.
Shoko Fujiwara Mitsuhiro Sawada Junichiro Someya Nobuhiro Minaka Masanobu Kawachi Isao Inouye 《Journal of phycology》1994,30(5):863-871
The nucleotide sequences of rbcL genes encoding the large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) were determined from six species of Prymnesiophyta to clarify their phylogenetic relationships. Molecular phylogenetic trees were constructed using PAUP (Phylogenetic Analysis Using Parsimony). These analyses suggest that the Prymnesiophyta, except for the Pavlovales, area relatively stable monophyletic group. Pleurochrysis carterae, included in the Isochrysidales, is a sister species of a monophyletic group consisting of other members of the Isochrysidales, Gephyrocapsa oceanica and Emiliania huxleyi, members of the Coccosphaerales, Calyptrosphaera sphaeroidea and Umbilicosphaera sibogae var. foliosa, and a member of the Prymnesiales, Chrysochromulina hirta. The nucleotide sequence of rbcL from G. oceanica was identical to that from E. huxleyi within the region examined. Our trees show that G. oceanica and E. huxleyi are more closely related to C. hirta than to U. sibogae, C. sphaeroidea, and P. carterae. These results suggest that orders in the Prymnesiophyceae, including the above-mentioned genera, should be redefined. 相似文献
5.
Kumiko Ui Shoko Nishihara M. Sakuma S. Togashi R. Ueda Y. Miyata T. Miyake 《In vitro cellular & developmental biology. Animal》1994,30(4):209-216
Summary From the central nervous system ofDrosophila melanogaster 3rd instar larvae, eight continuous cell lines have been established (named ML-DmBG1 to 8). Using ML-DmBG2, single colony
isolation was carried out and six colonial clones were obtained. All reacted to the antibody to horseradish peroxidase, which
is a neuronal marker in insects. Acetylcholine, a known neurotransmitter inDrosophila, was detected in three of the colonial clones by high performance liquid chromatography. Therefore, it is concluded that
the established colonial clones are neural cells originating in the larval central nervous system. Among them, some variation
was observed with respect to morphology, acetylcholine content, and reactivity to anti-HRP. The variation may reflect the
heterogeneity of cells composing the central nervous system. 相似文献
6.
7.
Ariana M. Chao Thomas A. Wadden Robert I. Berkowitz George Blackburn Paula Bolin Jeanne M. Clark Mace Coday Jeffrey M. Curtis Linda M. Delahanty Gareth R. Dutton Mary Evans Linda J. Ewing John P. Foreyt Linda J. Gay Edward W. Gregg Helen P. Hazuda James O. Hill Edward S. Horton Denise K. Houston John M. Jakicic Robert W. Jeffery Karen C. Johnson Steven E. Kahn William C. Knowler Anne Kure Katherine L. Michalski Maria G. Montez Rebecca H. Neiberg Jennifer Patricio Anne Peters Xavier Pi‐Sunyer Henry Pownall David Reboussin Bruce Redmon W. Jack Rejeski Helmut Steinburg Martha Walker Donald A. Williamson Rena R. Wing Holly Wyatt Susan Z. Yanovski Ping Zhang 《Obesity (Silver Spring, Md.)》2020,28(5):893-901
8.
Shoko Nakano Yuko Abe Kimiko Nakajima Shigetoshi Sano Osamu Yamamoto Kazumasa Wakamatsu Shosuke Ito Masahiro Hayashi Tamio Suzuki 《Pigment cell & melanoma research》2021,34(1):101-110
Post‐inflammatory hyperpigmentation (PIH) is a common cutaneous condition that can cause a disfigured appearance. However, the pathophysiology of PIH remains poorly understood, at least in part, because an appropriate animal model for research has not been established. In order to analyze the pathomechanism of PIH, we successfully induced PIH in a hairless version of transgenic mice (hk14‐SCF Tg/HRM) that have a human‐type epidermis containing melanin by repeated hapten application of 2,4‐dinitrofluorobenzene. Histopathologic observation showed epidermal hyperplasia, predominant infiltrations of inflammatory cells, and melanin‐containing cells in the dermis just after elicitation of the atopic dermatitis‐like condition. At week 2, the findings were similar to the characteristics of PIH, that is, an increase of melanin without spongiosis or liquid degeneration in the epidermis and an increase in dermal melanophages. Dynamic analysis of melanin showed that the melanin in the dermis remained for a longer duration than in the epidermis. Furthermore, immunohistochemical staining revealed that the majority of cells containing melanin were positive for the anti‐CD68 antibody, but negative for the anti‐F4/80 antibody. These data suggest that novel treatments of PIH should be targeted against macrophages and should eventually lead to the development of new treatment modalities. 相似文献
9.
Background
The functional polymorphism Val158Met in the catechol-O-methyltransferase (COMT) gene has been associated with differences in prefrontal cognitive functions in patients with schizophrenia and healthy individuals. Several studies have indicated that the Met allele is associated with better performance on measures of cognitive function. We investigated whether the COMT Val158Met genotype was associated with cognitive function in 149 healthy controls and 118 patients with schizophrenia.Methods
Cognitive function, including verbal memory, working memory, motor speed, attention, executive function and verbal fluency, was assessed by the Brief Assessment of Cognition in Schizophrenia (BACS-J). We employed a one-way analysis of variance (ANOVA) and a multiple regression analysis to determine the associations between the COMT Val158Met genotype and the BACS-J measurements.Results
The one-way ANOVA revealed a significant difference in the scores on the Tower of London, a measure of executive function, between the different Val158Met genotypes in the healthy controls (p = 0.023), and a post-hoc analysis showed significant differences between the scores on the Tower of London in the val/val genotype group (18.6 ± 2.4) compared to the other two groups (17.6 ± 2.7 for val/met and 17.1 ± 3.2 for met/met; p = 0.027 and p = 0.024, respectively). Multiple regression analyses revealed that executive function was significantly correlated with the Val158Met genotype (p = 0.003). However, no evidence was found for an effect of the COMT on any cognitive domains of the BACS-J in the patients with schizophrenia.Conclusion
These data support the hypothesis that the COMT Val158Met genotype maintains an optimal level of dopamine activity. Further studies should be performed that include a larger sample size and include patients on and off medication, as these patients would help to confirm our findings. 相似文献10.
Mastitis, inflammation of the mammary gland, is the most costly common disease in the dairy industry, and is caused by mammary pathogenic bacteria, including Escherichia coli. The bacteria invade the mammary alveolar lumen and disrupt the blood-milk barrier. In normal mammary gland, alveolar epithelial tight junctions (TJs) contribute the blood-milk barrier of alveolar epithelium by blocking the leakage of milk components from the luminal side into the blood serum. In this study, we focused on claudin subtypes that participate in the alveolar epithelial TJs, because the composition of claudins is an important factor that affects TJ permeability. In normal mouse lactating mammary glands, alveolar TJs consist of claudin-3 without claudin-1, -4, and -7. In lipopolysaccharide (LPS)-induced mastitis, alveolar TJs showed 2-staged compositional changes in claudins. First, a qualitative change in claudin-3, presumably caused by phosphorylation and participation of claudin-7 in alveolar TJs, was recognized in parallel with the leakage of fluorescein isothiocyanate-conjugated albumin (FITC-albumin) via the alveolar epithelium. Second, claudin-4 participated in alveolar TJs with claudin-3 and claudin-7 12 h after LPS injection. The partial localization of claudin-1 was also observed by immunostaining. Coinciding with the second change of alveolar TJs, the severe disruption of the blood-milk barrier was recognized by ectopic localization of β-casein and much leakage of FITC-albumin. Furthermore, the localization of toll-like receptor 4 (TLR4) on the luminal side and NFκB activation by LPS was observed in the alveolar epithelial cells. We suggest that the weakening and disruption of the blood-milk barrier are caused by compositional changes of claudins in alveolar epithelial TJs through LPS/TLR4 signaling. 相似文献