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601.
Investigation into arthritis, as well as numerous bone phenotypes found in mice lacking immune-related genes, has highlighted the importance of the interplay between the bone and immune systems, which has led to the emergence and evolution of the field of osteoimmunology. RANKL stimulates osteoclastogenesis through nuclear factor of activated T cells (NFAT) c1, which is also a crucial regulator of immunity. In rheumatoid arthritis, bone destruction is caused by the enhanced activity of osteoclasts, which is mainly dependent on interleukin-17-producing helper T cells (TH17). The scope of osteoimmunology has been extended to encompass a wide range of molecular and cellular interactions. The framework of osteoimmunology will provide a scientific basis for future therapeutic approaches to diseases related to both of these systems. 相似文献
602.
Aoyama T Okamoto T Kohno Y Fukiage K Otsuka S Furu M Ito K Jin Y Nagayama S Nakayama T Nakamura T Toguchida J 《Biochemical and biophysical research communications》2008,365(1):124-130
The expression of the chondromodulin-I (ChM-I) gene, a cartilage-specific gene, is regulated by the binding of Sp3 to the core promoter region, which is inhibited by the methylation of CpG in the target genome in the osteogenic lineage, osteosarcoma (OS) cells. The histone tails associated with the hypermethylated promoter region of the ChM-I gene were deacetylated by histone deacetylase 2 (HDAC2) in three ChM-I-negative OS cell lines. Treatment with an HDAC inhibitor induced the binding of Sp3 in one cell line, which became ChM-I-positive. This process was associated with acetylation instead of the dimethylation of histone H3 at lysine 9 (H3-K9) and, surprisingly, the demethylation of the core promoter region. The demethylation was transient, and gradually replaced by methylation after a rapid recovery of histone deacetylaion. These results represent an example of the plasticity of differentiation being regulated by the cell-specific plasticity of epigenetic regulation. 相似文献
603.
Inoue K Nakanjishi M Kikuchi H Yamamoto H Todo S Nakagawara A Ozaki T 《Biochemical and biophysical research communications》2008,371(4):829-833
In response to DNA damage, NFBD1/MDC1 induces the accumulation of DNA repair machinery such as MRN complex at the sites of damaged DNA to form nuclear foci. In this study, we found that NFBD1 directly interacts with MDM2 and increases its stability. During adriamycin (ADR)-mediated apoptosis, expression levels of NFBD1 reduced in association with the down-regulation of MDM2. Enforced expression of NFBD1 resulted in a significant stabilization of MDM2. Consistent with these observations, siRNA-mediated knockdown of the endogenous NFBD1 decreased the amounts of the endogenous MDM2. Immunoprecipitation and in vitro pull-down assays demonstrated that NFBD1 interacts with MDM2 through its COOH-terminal BRCT domains. In accordance with our recent results, enforced expression of NFBD1 rendered cells resistant to DNA damage. Similar results were also obtained in cells expressing exogenous MDM2. Taken together, our present findings suggest that NFBD1-mediated stabilization contributes to cell survival in response to DNA damage. 相似文献
604.
Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. Studies assessing serum levels
of the micronutrients and magnitude of their deficiencies are very scarce in African subjects. This study was aimed at determining
serum levels of micronutrients in 375 pregnant (42 HIV seropositive) and 76 non-pregnant women (20 HIV seropositive) who visited
the University of Gondar Hospital, Gondar, Ethiopia. Serum concentrations of zinc,\ copper, selenium, calcium, and magnesium
were determined using an inductively coupled plasma mass spectrometer. Irrespective of HIV serostatus, pregnant women had
significantly higher serum concentrations of copper and copper/zinc ratio and significantly lower magnesium compared to those
in non-pregnant women (P < 0.05). Except for selenium, which was significantly lower in HIV-seropositive pregnant women (P < 0.05), the mean serum concentrations of zinc, copper, calcium, and magnesium were not significantly different between pregnant
women by HIV serostatus. The prevalence of deficiency in zinc, magnesium, selenium, and calcium in the pregnant women, irrespective
of their HIV serostatus, was 66.7%, 25.6%, 21.9%, and 9.3%, respectively. The magnitude of deficiency in zinc, magnesium,
and selenium was significantly higher in HIV seropositive pregnant women (76.2%, 52.4%, and 45.2%) than that in HIV-seronegative
pregnant women (65.5%, 22.2%, and 18.9%) and in HIV-seronegative non-pregnant women (42.9%, 8.1%, and 30.4%; P < 0.05). Deficiency in one, two, three, or four mineral elements was observed in 44.8%, 14.4%, 9.9%, and 5.1% of the pregnant
women, respectively. Only 25.9% of the pregnant women and 44.7% of the non-pregnant women were not deficient in any of the
micronutrients. The high prevalence of micronutrient deficiencies in pregnant and non-pregnant women in Gondar, Ethiopia warrants
the need for strategies on prevention and control of the deficiencies. 相似文献
605.
606.
The significance of elongation of the first and second spines of the first dorsal fin in male Eviota abax (Gobiidae) was examined in relation to female preference. Reproductive behavior occurred in three phases: male approach to
female home, male leading female to nest, and male entering nest. During each phase, the female either accompanied the male
or departed. The ratio of positive female mating responses to males before the elongated male dorsal spines were clipped and
thereafter was compared in an aquarium. Females preferred male elongated spines in the first phase of courtship, but not in
the second phase . Because females may be more exposed to predators during the second phase, owing to conspicuous male courtship,
their greater receptivity to elongated dorsal spines in the first phase may decrease predation pressures during subsequent
phases of courtship.
Electronic Publication 相似文献
607.
Sakaguchi Masayoshi Matsushima Yudai Nagamine Yusuke Matsuhashi Tomoki Honda Shotaro Okuda Shoi Ohno Misa Sugahara Yasusato Shin Yongchol Oyama Fumitaka Kawakita Masao 《Applied microbiology and biotechnology》2017,101(6):2415-2425
Applied Microbiology and Biotechnology - Clostridium sp. G0005 glucoamylase (CGA) is composed of a β-sandwich domain (BD), a linker, and a catalytic domain (CD). In the present study, CGA was... 相似文献
608.
Sunobe T Nakamura M Kobayashi Y Kobayashi T Nagahama Y 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2005,141(1):54-59
The role of aromatase (Arom) in the process of bi-directional sex change in the gobiid fish Trimma okinawae was investigated by immunohistochemical methods. Irrespective of sexual phase, gonads comprised both ovarian and testicular tissues. In each sexual phase of females, the 2nd (2DF-M) and 4th (4DF-M) days after initiation of sex change to male, males, and the 2nd (2DM-F), 4th (4DM-F) and 6th (6DM-F) days after the initiation of reversion from male to female, ovarian and testicular histological observations were made. During the female, 2DF-M, 4DF-M and 6DM-F phases, the ovary contained vitellogenic and previtellogenic oocytes, compared with previtellogenic oocytes in the other phases. Although sperm was found in the testis in every phase, sperm ducts were apparent in the male phase, but not the female phase. Arom immunoreactivity was detected in the interstitial cells between the oocytes in all phases. On the other hand, it was localized in the thecal and granulosa cells of the follicular layer enclosing the oocytes in the female, 2DF-M, 4DF-M and 6DM-F phases. Activity of Arom in the thecal and granulosa cells is thought to be important for the development of oocytes and subsequent sex change. 相似文献
609.
Interspecific competition for spawning sites between two gobiid fishes, Bathygobius fuscus and Eviota abax, was studied on a rocky shore. Large males (LM: 55–80mm in standard length: SL) and small males (SM: 34–52mm SL) of B. fuscus acted as nest holders and sneakers, respectively, in the early spawning season (July). The sympatric male E. abax (22–33mm SL) was smaller than SM B. fuscus, and synchronically used rocky holes much smaller than those of LM B. fuscus. In this season, aggressions between the two species were rarely observed. In late season (August), as the number of the LM decreased, the SM converted their tactics to nest holding, occupying nests of a sizes similar to those of E. abax. Eviota abax males were dispossessed by SM and shifted their nest sites to cavities between cobbles and sandy bottom, which might be poorer nest sites than rocky holes. 相似文献
610.
The cryptochromes 总被引:3,自引:0,他引:3
Cryptochromes are photoreceptors that regulate entrainment by light of the circadian clock in plants and animals. They also
act as integral parts of the central circadian oscillator in animal brains and as receptors controlling photomorphogenesis
in response to blue or ultraviolet (UV-A) light in plants. Cryptochromes are probably the evolutionary descendents of DNA
photolyases, which are light-activated DNA-repair enzymes, and are classified into three groups - plant cryptochromes, animal
cryptochromes, and CRY-DASH proteins. Cryptochromes and photolyases have similar three-dimensional structures, characterized
by an α/β domain and a helical domain. The structure also includes a chromophore, flavin adenine dinucleotide (FAD). The FAD-access
cavity of the helical domain is the catalytic site of photolyases, and it is predicted also to be important in the mechanism
of cryptochromes. 相似文献