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91.
 Osteopontin is a sialoprotein that is expressed in various cells. It plays a variety of important roles in cell adhesion, migration, signaling, calcification, and immunity. Its diverse functions indicate that the regulation of osteopontin may also vary extensively among tissues. Although osteopontin promoter has been studied in vitro, in vivo analyses may be more appropriate for elucidating osteopontin's functions. In an attempt to investigate osteopontin gene expression, we generated transgenic mice in which the bacterial β-galactosidase reporter gene was conjugated downstream of osteopontin promoter. The osteopontin promoter was a mouse −910 bp upstream fragment, which we had previously found functional in 3T3 cells. Among 34 transgenic founders, 13 mice were transgenic, as determined with the polymerase chain reaction. Osteopontin and β-galactosidase signals were evaluated with in situ hybridization. Among the 13 transgenic mice, 3 were β-galactosidase-positive. In these transgenic mice, osteopontin signals were observed in bones and kidneys, whereas β-galactosidase message was detected only in bones. This suggests that the −910 bp osteopontin promoter is active in bones but not in kidneys. These data imply that the promoter region required for osteopontin expression in kidneys may differ from that in bones. Received: March 22, 2002 / Accepted: December 5, 2002 RID="*" ID="*" Offprint requests to: T. Sakuma Acknowledgments. We greatly appreciate the excellent histotechnological assistance of Mr. Kenji Morihana. This work was supported in part by a grant from The Ministry of Education, Science, and Culture, Japan (no. 12470056).  相似文献   
92.
OBJECTIVES: We investigated the occurrence of inflammatory paradental cysts (IPC) in the mandibular premolar, and demonstrated the points of difference with regard to diagnostic features between IPC and dentigerous cysts (DC). MATERIAL AND METHODS: We analyzed the radiographs and histology of 60 cases with a cystic lesion associated with inflammation in the mandibular premolar region based on diagnostic criteria as IPC. RESULTS: In 4 out of 60 cases, we diagnosed the 4 cysts as IPCs in the mandibular premolar region, and recognized that one form of IPC was similar to a mandibular infected buccal cyst. The other 56 non-IPC cases were diagnosed as DC. On the IPCs, the permanent tooth normally erupted in all 4 cases after treatment, but in one case, the IPC recurred. CONCLUSIONS: The present investigation suggested that we might have misdiagnosed IPCs in the mandibular premolar region as DC to date. It is important to consider the differences between IPC and DC with regard to the causes of recurrence during treatment of IPC.  相似文献   
93.
It has long been held that the parathyroid glands and parathyroid hormone evolved with the emergence of the tetrapods, reflecting a need for new controls on calcium homeostasis in terrestrial, rather than aquatic, environments. Developmentally, the parathyroid gland is derived from the pharyngeal pouch endoderm, and studies in mice have shown that its formation is under the control of a key regulatory gene, Gcm-2. We have used a phylogenetic analysis of Gcm-2 to probe the evolutionary origins of the parathyroid gland. We show that in chicks, as in mice, Gcm-2 is expressed in the pharyngeal pouches and the forming parathyroid gland. We find that Gcm-2 is present not only in tetrapods but also in teleosts and chondrichthyans, and that in these species, Gcm-2 is expressed within the pharyngeal pouches and internal gill buds that derive from them in zebrafish (Danio rerio), a teleost, and dogfish (Scyliorhinus canicula), a chondrichthyan. We further demonstrate that Gcm-2 is required for the formation of the internal gill buds in zebrafish. We also have identified parathyroid hormone 1/2-encoding genes in fish and show that these genes are expressed by the gills. We further show that the gills express the calcium-sensing receptor, which is used in tetrapods to monitor serum calcium levels. These results indicate that the tetrapod parathyroid gland and the gills of fish are evolutionarily related structures, and that the parathyroid likely came into being as a result of the transformation of the gills during tetrapod evolution.  相似文献   
94.
A disintegrin and metalloproteinase 3 (ADAM3) is a sperm membrane protein critical for both sperm migration from the uterus into the oviduct and sperm primary binding to the zona pellucida (ZP). Here we show that the testis-specific protein disulfide isomerase homolog (PDILT) cooperates with the testis-specific calreticulin-like chaperone, calsperin (CALR3), in the endoplasmic reticulum and plays an indispensable role in the disulfide-bond formation and folding of ADAM3. Pdilt(-/-) mice were male infertile because ADAM3 could not be folded properly and transported to the sperm surface without the PDILT/CALR3 complex. Peculiarly we find that not only Pdilt(-/-), but also Adam3(-/-), spermatozoa effectively fertilize eggs when the eggs are surrounded in cumulus oophorus. These findings reveal that ADAM3 requires testis-specific private chaperones to be folded properly and that the principle role of ADAM3 is for sperm migration into the oviduct but not for the fertilization event. Moreover, the importance of primary sperm ZP binding, which has been thought to be a critical step in mammalian fertilization, should be reconsidered.  相似文献   
95.
The working group for the future planning of the Japanese Association of Anatomists (JAA) has been working to address the issues that were consulted from the president of JAA since October 2009. After making the interim report in March 2010, a public hearing for general members of the JAA was held and a final report was submitted to the President in January 2011. The report contains the analysis of the current situation, the directions in which we should proceed, and recommendations of concrete actions that JAA should take for each issue. The issues discussed were as follows: 1. Future prospects of anatomy and morphological sciences. How can we maintain the specialties of morphological and anatomical sciences in the rapidly advancing field of life sciences and develop collaborations with other fields? 2. Improvement of the JAA academic meetings. How can we increase JAA members and young participants in the academic meetings of the JAA? 3. Fostering the next generation of young researchers. How can we increase young researchers graduated from the schools of Medicine or Dentistry? 4. Future prospects of education of gross anatomy. Prospects of education in gross anatomy and the body donation registration system in relation with some new cadaver-related movements.  相似文献   
96.
In this study, we tried to clarify the prevalence of suicidal ideation and self-mutilation including suicide attempts among patients with gender identity disorder (GID) and the relationship of those behaviors to demographic characteristics. A total of 500 consecutive Japanese GID patients without any other psychiatric comorbidity were evaluated at the outpatient GID Clinic of Okayama University Hospital. The lifetime rate of suicidal ideation was 72.0% of the total sample. There were no significant differences in the prevalence of suicidal ideation among groups divided by sex, age, age at onset or education. The lifetime prevalence of self-mutilation including suicide attempts was 31.8% of the total sample. Low level of education was significantly related to self-mutilation among both male-to-female and female-to-male GID patients. Younger age at onset was a significant factor affecting self-mutilation only among MTF GID patients. A lack of strategies to cope with severe distress among persons with lower education might induce a high frequency of self-mutilation including suicidal attempt. GID patients with a low level education might be at high risk of self-mutilation and should be watched with special attention to self-mutilation.  相似文献   
97.
98.
BACKGROUND: A new electronic mesh nebulizer, eMotion is known to have higher performance compared to conventional nebulizers. However, there are some concerns about whether too much delivered dose might cause side effects with higher frequency. METHODS: To evaluate the safety and usefulness of the nebulizer, we measured changes in heart rates and lung functions of 73 asthmatic children when they inhaled 1 microg/kg of procaterol with eMotion or a conventional nebulizer, Junior BOY. RESULTS: In 34 children with mild asthma exacerbation, physical findings, lung function and transcutaneous oxygen saturation levels were improved after inhalation using both nebulizers. No adverse effects including significant increase of heart rate were found. Improvements in the rates of the parameters were comparable. When response to beta2-agonist inhalation was checked in 39 children in stable condition, similar degrees of improvement in lung function were observed, and heart rates did not change after inhalation with either nebulizers. CONCLUSIONS: Safety and efficacy was comparable between eMotion and a conventional nebulizer when it was used to administer beta2-agonists in asthmatic children. However, from the fact that eMotion needs only 3-4 minutes to inhale 2 mL solution, eMotion could be more useful for most children who usually do not prefer longer inhalation time with conventional compressor nebulizers.  相似文献   
99.
Bone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH). This finding may provide an initial step in innovative autograft cell transfer therapy for steroid hormone deficiencies.  相似文献   
100.
Whereas local microglial cells of the CNS rapidly respond to injury, little is known about the functional role of resident macrophages of the peripheral nervous system in nerve pathology. Using bone marrow chimeric rats, we recently identified individual resident endoneurial macrophages that rapidly became activated after nerve injury. However, the extent of local macrophage activation and its quantitative contribution to the total macrophage response is unknown. We now have created chimeric mice by transplanting bone marrow from green fluorescent protein (GFP)-transgenic mice into irradiated wild-type mice, allowing easy differentiation and quantification of hematogenous and resident endoneurial macrophages. After sciatic nerve crush injury, both GFP(-) and GFP(+) resident macrophages, the latter having undergone physiological turnover from the blood before injury, rapidly underwent morphological alterations and increased in number. Proliferating GFP(-) and GFP(+) resident macrophages were abundant and peaked 3 days after injury. A major lesion-induced influx of hematogenous macrophages with a disproportionate increase of GFP(+) macrophages was not observed until Day 4. Throughout all time points examined, GFP(-) resident macrophages were strikingly frequent, reaching maximum numbers 9.5-fold above baseline. There was also a notable proportion of GFP(-) resident endoneurial macrophages phagocytosing myelin and expressing major histocompatibility complex class II. Our results demonstrate for the first time that the rapid response of resident endoneurial macrophages to nerve injury is quantitatively important and that local macrophages contribute significantly to the total endoneurial macrophage pool during Wallerian degeneration.  相似文献   
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