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31.
32.
Takuya Kishimoto Ting-Ting Liu Hiroyasu Hatakeyama Tomomi Nemoto Noriko Takahashi Haruo Kasai 《The Journal of physiology》2005,568(3):905-915
We investigated exocytosis of PC12 cells using two-photon excitation imaging and extracellular polar tracers (TEP imaging) at the basal region of PC12 cells adjacent to the glass cover slip. TEPIQ (two-photon extracellular polar-tracer imaging-based quantification) analysis revealed that most exocytosis was mediated by large dense-core vesicles (LVs) with a mean diameter of 220 nm, and that exocytosis of LVs occurred slowly with a mean latency of ∼7 s even though exocytosis was induced with large increases in cytosolic Ca2 + concentration by uncaging of a caged-Ca2 + compound. We also found that 97% of exocytic LVs remained poised at the plasma membrane, 72% maintained their fusion pores in an open conformation for more than 30 s, and 76% triggered sequential compound exocytosis of vesicles that were located deeper in the cytosol. Sequential compound exocytosis by PC12 cells was confirmed by electron microscopic investigation with photoconversion of diaminobenzidine by FM1-43 (a polar membrane tracer). Our data suggest that pre-stimulus docking of LVs to the plasma membrane does not necessarily hasten the fusion reaction, while docking and resulting stability of exocytic LVs facilitates sequential compound exocytosis, and thereby allowing mobilization of deep vesicles. 相似文献
33.
Horike S Mitsuya K Meguro M Kotobuki N Kashiwagi A Notsu T Schulz TC Shirayoshi Y Oshimura M 《Human molecular genetics》2000,9(14):2075-2083
Human chromosome 11p15.5 harbors an intriguing imprinted gene cluster of 1 Mb. This imprinted domain is implicated in a wide variety of malignancies and Beckwith-Wiedemann syndrome (BWS). Recently, several lines of evidence have suggested that the BWS-associated imprinting cluster consists of separate chromosomal domains. We have previously identified LIT1, a paternally expressed antisense RNA within the KvLQT1 locus through a positional screening approach using human monochromosomal hybrids. KvLQT1 encompasses the translocation breakpoint cluster in BWS and patients exhibit frequent loss of maternal methylation at the LIT1 CpG island, implying a regulatory role for the LIT1 locus in coordinate control of the imprinting cluster. Here we generated modified human chromosomes carrying a targeted deletion of the LIT1 CpG island using recombination-proficient chicken DT40 cells. Consistent with the prediction, this mutation abolished LIT1 expression on the paternal chromosome, accompanied by activation of the normally silent paternal alleles of multiple imprinted loci at the centromeric domain including KvLQT1 and p57(KIP2). The deletion had no effect on imprinting of H19 located at the telomeric end of the cluster. Our findings demonstrate that the LIT1 CpG island can act as a negative regulator in cis for coordinate imprinting at the centromeric domain, thereby suggesting a role for the LIT1 locus in a BWS pathway leading to functional inactivation of p57(KIP2). Thus, the targeting and precise modification of human chromosomal alleles using the DT40 cell shuttle system can be used to define regulatory elements that confer long-range control of gene activity within chromosomal domains. 相似文献
34.
Chikako?IkebeEmail author Masaki?Kuro-o Hiromi?Ohtani Yoshie?Kawase Tomomi?Matsui Sei-ichi?Kohno 《Chromosome research》2005,13(2):157-167
Using Giemsa staining, C-banding and Ag-NOR staining techniques, we analyzed chromosomes in adult male and female Hynobius quelpaertensis and in embryos of this species in egg sacs collected from eight localities of Cheju Island, South Korea. Chromosome pair
21 was consistently homomorphic in male specimens, while it was heteromorphic in female specimens, suggesting the occurrence
of ZZ/ZW sex chromosome constitution in this species. The W chromosome, being much larger than the Z chromosome, was of three
morphologically distinct types: WA, WB and WC. Lampbrush chromosomes examined in the oocytes of one female specimen having the WA chromosome showed that the short arm of the WA chromosome and the long arm of the Z chromosome paired closely and hence are genetically homologous. We also tried to analyze
the structural relationship among the three types of W chromosomes based on their C-banding and Ag-NOR patterns. 相似文献
35.
Kazuyasu Endo Akiyoshi Sato Tomohiro Sugawara Junichi Kameoka Osamu Fukuhara Kuniaki Meguro Tomoaki Shishido Keishi Abe 《Cancer Genetics and Cytogenetics》1995,80(2):155-157
A 46-year-old man with chronic myelogenous leukemia was found to have a new complex translocation. In chronic phase, all of the bone marrow cells had a rearrangement of a t(2;9;14;22) (p21;q34;q32;q11). Southern blot analysis of leukocyte DNA revealed rearrangement of the breakpoint cluster region (bcr) within the 5.8-Kb bcr. The patient eventually died in blast crisis 28 months later. The cytogenetic findings of bone marrow cells showed a 46,XY,t(2;9;14;22)(p21;q34;q32;qll),add(lp),del(3q) karyotype in blast crisis. 相似文献
36.
Kameoka J Funato T Obara Y Kadowaki I Yokoyama H Kimura T Tomiya Y Yamada M Ishikawa I Takagawa M Sasaki O Kimura J Harigae H Miura I Meguro K Kaku M Sasaki T 《Cancer Genetics and Cytogenetics》2001,124(2):159-164
Tetrasomy 8, though rare, is usually associated with trisomy 8, a far more common chromosomal abnormality in acute myeloid leukemia (AML). Yet the clonal relationship between trisomy 8 and tetrasomy 8 in the cases with these chromosomal abnormalities has been unclear. Here, we report a case of a 17-year-old male, diagnosed as having a myelodysplastic syndrome (MDS). Chromosome analysis showed the presence of trisomy 8. Five years later, he developed overt AML exhibiting tetrasomy 8 only. After chemotherapy, the blast cells in the bone marrow decreased to 3.4%, and the karyotype showed trisomy 8 alone. Fluorescence in situ hybridization using a probe specific for chromosome 8 showed that the percentages of cells exhibiting 2/ 3 /4 signals were 7.8/89.2/2.0 at the MDS stage, 20.5/36.1/41.0 when overt AML developed and 24.0/72.1/2.4 after chemotherapy. These results suggested that tetrasomy 8 is derived from the AML clone, possibly evolved from the MDS clone with trisomy 8. To our knowledge, this is the first detailed case report of clonal evolution from trisomy 8 into tetrasomy 8 associated with the development of AML from MDS. 相似文献
37.
R Fujii H Meguro O Arimasu K Tamura F Hiruma M Hori Y Toyonaga M Sugita K Kuno N Iwai 《The Japanese journal of antibiotics》1986,39(5):1279-1296
We have attempted to clinically define the therapeutic usefulness of ceftizoxime suppository (CZX-S) in children with bacterial pneumonia, in a randomized trial. Intravenous injection of ceftizoxime (CZX) was used as the control. The results are summarized below. Subjects were inpatients with bacterial pneumonia, ranging in age from 9 months to 7 years and 10 months. As a rule, the daily dose was either four 250 mg (in potency) suppositories given at 6-hour intervals or 60 mg/kg body weight intravenous CZX (control) given in 4 injections at 6-hour intervals over a period of 7 days. The number of children in the study was 67. These children were divided into 2 dosage groups (suppository, 35; injection, 32) with matching pretreatment background factors. The severity of the target disease in the majority of the children was "moderate". The rate of therapeutic effectiveness was 97.1% for the suppository and 93.8% for the injection, and did not differ significantly between the 2 groups. Rates of efficacy by severity, presence or absence of underlying diseases, daily dose and/or complications were high without exception, and did not differ significantly between the 2 groups. Eradication rates for causative microorganisms, as studied in 16 children of each group, were both 93.8%. The 2 most frequently isolated causative organisms were Haemophilus influenzae and Streptococcus pneumoniae. Side effects were examined for 36 children of each group. The frequency of side effects did not differ significantly between the suppository group (2 with diarrhea and 1 with abdominal pain) and the injection group (1 with urticaria), and 8.3% and 2.8%, respectively. The frequency of abnormal laboratory test findings differed significantly (P less than 0.01) with respect to eosinophilia which occurred in 7 (20.6%) of the injected subjects but was not encountered in the subjects treated with suppositories. Other abnormal laboratory findings included thrombocytosis in 3 (14.3%) of the injection group and increased GOT in 1 (3.2%) of the suppository group. The suppository formulation of CZX appears to be a highly useful substitute for the injectable form, and should find a special use in children whose treatment with injections experiences some difficulty. 相似文献
38.
Takaomi Sagawa Tomomi Kogiso Taito Ito Hideo Yasuda Nagaaki Katoh Tsuneaki Yoshinaga Masahide Yazaki Takaaki Kato Akiko Omori Yoshihito Kotera Hiroto Egawa Masakazu Yamamoto Katsutoshi Tokushige 《Transplantation proceedings》2021,53(4):1327-1332
Hereditary apolipoprotein A-1 (ApoA-1) amyloidosis is a rare disease characterized by progressive deposition of amyloid fibrils in the kidney, heart, and liver. We observed a 45-year-old male patient with liver failure. Liver dysfunction was detected at 30 years of age during an annual health check-up. At 35 years of age, renal dysfunction was also found. At 40 years of age, the pathologic findings of the liver revealed amyloid deposition. A testis biopsy specimen taken at 42 years of age to identify the cause of male infertility showed amyloid accumulation. At 43 years of age, the amyloid results and genetic profile led to a definitive diagnosis of hereditary ApoA-1 amyloidosis caused by Glu34Lys mutation. A family history was absent. Liver failure showed Budd-Chiari–like formation, including enlargement of the caudate lobe and liver congestion. Although the patient showed end-stage liver cirrhosis and renal failure, only liver transplant was performed considering the burden for a living donor. The enlarged liver (4.9 kg) showed amyloid deposition in parenchyma and the space of Disse. Amyloid also accumulated in the giant spleen. The APOA1 mutation Glu34Lys is extremely rare, and in this case hepatic failure was successfully treated by liver transplant to both replace organ function and reduce production of the amyloidogenic ApoA-1–variant protein. Careful observation for reaccumulation of amyloidosis in the organ is required. 相似文献
39.
Wada Takehiko Ishimoto Takuji Nakaya Izaya Kawaguchi Takehiko Sofue Tadashi Shimizu Sayaka Kurita Noriaki Sasaki Sho Nishiwaki Hiroki Koizumi Masahiro Saito Shoji Nishibori Nobuhiro Oe Yuji Yoshida Mai Miyaoka Yoshitaka Akiyama Shin’ichi Itano Yuya Okazaki Masaki Ozeki Takaya Ichikawa Daisuke Oguchi Hideyo Kohsaka Satoshi Kosaka Shiho Kataoka Yuki Shima Hideaki Shirai Sayuri Sugiyama Kazuhiro Suzuki Tomo Son Daisuke Tanaka Tomomi Nango Eishu Niihata Kakuya Nishijima Yoko Nozu Kandai Hasegawa Midori Miyata Rei Yazawa Masahiko Yamamoto Yoshihiro Yamamoto Ryohei Shibagaki Yugo Furuichi Kengo Okada Hirokazu Narita Ichiei 《Clinical and experimental nephrology》2021,25(12):1277-1285
Clinical and Experimental Nephrology - 相似文献
40.
Takanori Abe Satoshi Saito Misaki Iino Tomomi Aoshika Yasuhiro Ryuno Tomohiro Ohta Mitsunobu Igari Ryuta Hirai Yu Kumazaki Yasuhiro Ebihara Mitsuhiko Nakahira Masashi Sugasawa Shin-ei Noda Shingo Kato 《Journal of radiation research》2021,62(1):104
The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study. 相似文献