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71.
Intraperitoneal administration in mice of crude extract (CE) or maintenance fluid (MF) of Ascaris suum in Freund's incomplete adjuvant (FICA) in doses of 200 and 2 (CE) and 4 μg (MF) on Days ?4, 0, and +4 relative to the day of the immunization with 10 μg of hen egg white lysozyme (HL) resulted in the suppression of anti-HL reaginic antibody responses at varying degrees depending on the dose and their time of administration. Hemagglutinating antibody responses were also affected but in a different manner. Treatment with CE on Day ?4 resulted in complete suppression of reaginic antibody responses and some degree of suppression of hemagglutinating antibody responses depending on the size of the CE dose. In mice pretreated with MF, transient suppression was found only for reaginic antibody responses. In mice receiving the treatment of CE on Day 0, 200 μg of CE caused complete suppression of reaginic antibody responses, while 2 μg was less effective. Hemagglutinating antibody responses were also suppressed in proportion to the dose. Simultaneous treatment with MF did not cause any suppression of either reaginic or hemagglutinating antibody responses. In mice treated with CE on Day +4, reaginic antibody responses were not markedly suppressed and hemagglutinating antibody responses were also not altered. In contrast, treatment with MF on Day +4 resulted in suppression of reaginic antibody responses during the whole course of the primary response, but had no effect on hemagglutinating antibody responses. When MF was administered 7 days after the priming, no suppressive effect on the antibody responses was demonstrated. On the other hand, if a lower dose (1 μg of HL) was used for the priming, the effect of MF treatment with Day +4 was more pronounced in the primary reaginic antibody response and the secondary response was also affected. A comparable suppression of hemagglutinating antibody responses also was observed. 相似文献
72.
RNA nicking activity associated with DNA ligase of T4 infected E. coli: properties and influence on in vitro reactions of ligase. 下载免费PDF全文
Highly purified DNA ligase from T4 infected E. coli displays an RNA nicking activity which cleaves endonucleolytically the RNA of ribo-desoxy-and ribo-ribo type doublestranded structures to oligonucleotides with 5'phosphoryl-and 3'hydroxy termini. In the presence of ATP the generated nicks are repaired by the ligase except at the ends of the doublestranded regions where some short oligonucleotides are released before ligation can occur. As judged from its behaviour during the various purification steps and from some of its properties, the nicking activity seems to be different from known nicking enzymes. 相似文献
73.
74.
Kazuhiko Hashimoto Shunji Nishimura Tomohiko Ito Naohiro Oka Ryosuke Kakinoki Masao Akagi 《European journal of histochemistry : EJH》2022,66(3)
The cancer/testis antigens (CTAs), New York esophageal squamous cell carcinoma-1 (NY-ESO-1) and melanoma antigen gene (MAGE)-A4 are normally restricted to male germ cells but are aberrantly expressed in several cancers. Considering the limited information regarding their significance in osteosarcoma (OS), the purpose of this study was to determine the clinical significance of NY-ESO-1 and MAGE-A4 expression in OS. Nine patients with OS treated at Kindai University Hospital were included in the study. The median age was 27 years, and median follow-up period was 40 months. The specimens obtained at the time of biopsy were used to perform immunostaining for NY-ESO, MAGE-A4, p53, and Ki-67. The positive cell rates and positive case rates of NY-ESO, MAGE-A4, p53, and Ki-67 were calculated. The correlation between the positive cell rate of immunohistochemical markers was also calculated. The correlation between the positive cell rate of NY-ESO-1 or MAGE-A4 and tumor size or maximum standardized uptake (SUV-max) was also determined. The positive cell rates of NY-ESO-1 or MAGE-A4 in continuous disease-free (CDF) cases were also compared with those in alive with disease (AWD) or dead of disease (DOD) cases. The average positive cell rates of NY-ESO, MAGEA4, p53, and Ki-67 were 71.7%, 85.1%, 16.2%, and 14.7%, and their positive case rates were 33.3%, 100%, 44.4%, and 100%, respectively. The positivity rates of NY-ESO-1 and p53 were strongly correlated, whereas those of NY-ESO-1 and Ki-67 were moderately correlated. The MAGE-A4 and p53 positivity rates and the MAGE-A4 and Ki-67 positive cell rates were both strongly correlated. The NY-ESO-1 and MAGE-A4 positivity rates were moderately correlated. The positive correlation between the NY-ESO-1 positive cell rate and tumor size was medium, and that between the MAGE-A4 positivity rate and SUV-max was very strong. There was no significant difference in the positive cell rates of NY-ESO-1 or MAGE-A4 between CDF cases and AWD or DOD cases. Overall, our results suggest that NY-ESO-1 and MAGE-A4 may be involved in the aggressiveness of OS.Key words: New York esophageal squamous cell carcinoma-1 (NY-ESO-1), melanoma antigen gene (MAGE)- A4, osteosarcoma, prognosis, cancer/testis antigen (CTA), immunohistochemistry 相似文献
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76.
Tomohiko Maehama Masayoshi Fukasawa Tomoko Date Takaji Wakita Kentaro Hanada 《Biochemical and biophysical research communications》2013
Phosphoinositides function as fundamental signaling molecules and play roles in diverse cellular processes. Certain types of viruses may employ host cell phosphoinositide signaling systems to facilitate their replication cycles. Here we demonstrate that the β isoform of class II PI3K (PI3K-C2β) plays an indispensable role in hepatitis C virus (HCV) propagation in human hepatocellular carcinoma cells. Knockdown of PI3K-C2β abrogated HCV propagation in the cell. Using an HCV replicon system, we found that knockdown of PI3K-C2β substantially repressed the full-genome replication, while showing relatively small reductions in sub-genome replication, in which structural proteins including core protein were deleted. We also found that HCV core protein showed the binding activity towards D4-phosphorylated phosphoinositides and overlapped localization with phosphatidylinositol 3,4-bisphosphate in the cell. These results suggest that the phosphoinositide generated by PI3K-C2β plays an indispensable role in the HCV replication cycle through the binding to HCV core protein. 相似文献
77.
A. Seto-Ohshima Y. Yamazaki N. Kawamura S. Kitajima M. Sano A. Mizutani 《Histochemistry and cell biology》1987,86(4):337-343
Summary Calmodulin (CaM) is a major calcium-binding protein in the brain, where its immunoreactivity is mainly localized in the neurons. In this study, ontogenical changes in the distribution of CaM in the nervous system of mouse embryos were investigated immunohistochemically using a specific antibody against CaM and an indirect immunoenzyme method. Immunoreactive staining was first observed in the marginal layer of the cranial neural tube after 9.5 days of gestation; thereafter, the amount of stained structures increased rapidly. Particularly intense staining was observed in the long neuronal processes extending from or into the brain and spinal cord primordia. Intense immunostaining was also observed in the optic nerve layer of early retinae from 12.5 days of gestation. The appearance of CaM immunoreactivity is thus an early event during neuronal differentiation, apparently concominant with the initiation of axon extension and the appearance of neurofilament proteins. 相似文献
78.
Hiromoto Hisada Motoaki Sano Hiroki Ishida Yoji Hata Masayuki Machida 《Applied microbiology and biotechnology》2013,97(11):4951-4956
The Aspergillus oryzae glucoamylase-encoding gene glaB is expressed specifically and strongly only during solid-state cultivation (SSC). To elucidate the basis for the specificity, the glaB promoter was analyzed by electrophoretic gel mobility shift assay (EMSA) which indicated two protein-binding elements from ?382 to ?353 and from ?332 to ?313. To confirm that these regions contained cis-elements, deletion analysis of the promoter was undertaken using β-glucuronidase as a reporter. The results of the deletion analysis were consistent with the EMSA results. The promoter missing the ?332 to ?313 element was not induced by low water activity stress during SSC. 相似文献
79.
Summary The sphincter zone of the rabbit iris sometimes contains terminals with small granular vesicles. These terminals correspond to yellowish-green fluorescent structures in the sphincter zone. The paired arrangement of a terminal containing these vesicles and one full of agranular vesicles might indicate dual innervation of sphincter muscles by sympathetic and parasympathetic fibers. The sympathetic component probably exerts an inhibitory action on the sphincter muscles.This investigation was supported by a research grant from the Ministry of Education, Japan. 相似文献
80.
Osamu Nunobiki Daisuke Sano Kyoko Akashi Taro Higashida Toshitada Ogasawara Hikari Akise Shinji Izuma Kiyo Torii Yoshiaki Okamoto Ichiro Tanaka Masatsugu Ueda 《Human cell》2016,29(2):91-95
To investigate the clinical significance of ALDH2 genetic polymorphisms in cervical carcinogenesis. ALDH2 polymorphisms together with human papillomavirus (HPV) types were examined in a total of 195 cervical smear in exfoliated cervical cell samples using Real-Time polymerase chain reaction (PCR) System. The frequency for the AG+AA genotype was seven in the normal group (70.0 %), 16 in the LSIL group (57.1 %), and 27 in the HSIL group (90.0 %). A significant difference was found between the LSIL and HSIL groups (P = 0.0064). Patients with HSIL lesions frequently had high-risk HPV infections and concurrently belonged to the AG+AA group. ALDH2 genotype in cervical cell samples may be associated with more severe precancerous lesions of the cervix in a Japanese population. 相似文献