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941.
Nucleotide sequences of the sporulation gene spo0A and its mutant genes of Bacillus subtilis 总被引:16,自引:3,他引:13 下载免费PDF全文
Jun Kudoh Toshihiko Ikeuchi 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(9):2665-2668
We have determined the nucleotide sequence of a 2375-base-pair DNA fragment, which contained the sporulation gene spo0A cloned from Bacillus subtilis. The sequence had only one long open reading frame consisting of 239 codons, which was found to correspond to the spo0A gene by comparing the nucleotide sequence of the wild-type gene with those of the mutant alleles. The calculated molecular weight of the product of the wild-type spo0A gene was 26,500. We found also a new mutation, sgi, which maps within the spo0A gene. This mutation relieves the growth inhibition of the host cells caused by a multicopy plasmid carrying the spo0A gene. The mutations spo0A12, spo0C9V, and sgi-1 were found to be an amber mutation at the 62nd codon, a missense at the 229th codon, and a frame-shift at the 223rd codon of the spo0A gene, respectively. 相似文献
942.
Masafumi Taniwaki Jun-ichi Edagawa Yoshiaki Sonoda Kazuhiro Nishida Shin-ichi Misawa Tatsuo Abe Tatsuro Takino Naoki Arizono 《Cancer Genetics and Cytogenetics》1983,10(1):59-65
A 70-year-old Japanese male with hemopoietic dysplasia is described. Cytogenetic investigation revealed an abnormal karyotype, 46,XY,del(5)(q13q33), in all metaphases examined at the time of diagnosis. Eight months later, a newly appearing abnormal hyperdiploid karyotype, 47,XY,5q?, +21, was observed in 74% of the cells analyzed, which was associated with evolution of the disease when a pathologic diagnosis of a myeloproliferative disorder was made. 相似文献
943.
Differential acoustic properties of early cartilage lesions in living human knee and ankle joints 总被引:2,自引:0,他引:2
Hattori K Takakura Y Ishimura M Tanaka Y Habata T Ikeuchi K 《Arthritis and rheumatism》2005,52(10):3125-3131
OBJECTIVE: Although numerous studies have been performed to determine whether there are histologic, biochemical, biomechanical, and metabolic differences between knee and ankle cartilage, none have investigated the presence of such differences in living human cartilage. We previously developed an ultrasonic evaluation system for articular cartilage that analyzes the A-mode echogram using wavelet transformation. The current study was undertaken to determine whether the acoustic properties of living human cartilage differ between knee and ankle joints. METHODS: Twenty-eight patients were subjected to ultrasonic evaluation under arthroscopy. After arthroscopic grading, the cartilage was measured using an ultrasonic probe. Two quantitative parameters were used, i.e., the maximum magnitude and the echo duration at the 95% interval of the maximum magnitude. RESULTS: In intact cartilage, the maximum magnitude and echo duration did not differ between the knee and the ankle. In lesional cartilage, in contrast, the maximum magnitude was higher, and the echo duration was shorter, in the ankle than in the knee. These differences were statistically significant. CONCLUSION: Ultrasound findings could be used to judge the degree of early cartilage degeneration in vivo on the basis of objective data such as the maximum magnitude and echo duration. Because we were unable to quantitatively analyze the biochemical and biomechanical properties of the cartilage in this study, our biochemical and biomechanical findings are based only on qualitative assessment. Nevertheless, the results indicate that this ultrasonic evaluation system may be useful for elucidating the processes of articular cartilage degeneration in osteoarthritis. 相似文献
944.
Lack of antigen-specific tissue remodeling in mice deficient in the macrophage galactose-type calcium-type lectin 1/CD301a 下载免费PDF全文
Macrophage galactose-type C-type lectins (MGLs), which were recently named CD301, have 2 homologues in mice: MGL1 and MGL2. MGLs are expressed on macrophages and immature dendritic cells. The persistent presence of granulation tissue induced by a protein antigen was observed in wild-type mice but not in mice lacking an endogenous, macrophage-specific, galactose-type calcium-type lectin 1 (MGL1) in an air pouch model. The anti-MGL1 antibody suppressed the granulation tissue formation in wild-type mice. A large number of cells, present only in the pouch of MGL1-deficient mice, were not myeloid or lymphoid lineage cells and the number significantly declined after administration of interleukin 1 alpha (IL-1alpha) into the pouch of MGL1-deficient mice. Furthermore, granulation tissue was restored by this treatment and the cells obtained from the pouch of MGL1-deficient mice were incorporated into the granulation tissue when injected with IL-1alpha. Taken together, MGL1 expressed on a specific subpopulation of macrophages that secrete IL-1alpha was proposed to regulate specific cellular interactions crucial to granulation tissue formation. 相似文献
945.
946.
947.
Yamagishi S Matsumoto T Numakawa T Yokomaku D Adachi N Hatanaka H Yamada M Shimoke K Ikeuchi T 《Brain research》2005,1038(2):223-230
We have recently reported that the ASK1-p38 MAPK pathway has an important role in the low potassium (LK)-induced apoptosis of cultured cerebellar granule neurons. In the present study, we observed that ERK1/2 were significantly activated 6 h after a change of medium from HK (high potassium) to LK. In addition, U0126, a specific inhibitor of MEKs, remarkably prevented the apoptosis of cultured cerebellar granule neurons. Then, we examined the mechanism underlying the activation of ERK1/2 in the LK-induced apoptotic pathway. The addition of SB203580, an inhibitor of p38 MAPK, suppressed the increase in the phosphorylation of ERK1/2 after the change to LK medium. Furthermore, we found that the expression of a constitutively active mutant of ASK1, an upstream kinase of p38 MAPK, enhanced the phosphorylation of ERK1/2. These results suggest that ERK1/2 play a crucial role in LK-induced apoptosis of cultured cerebellar granule neurons and that the LK-stimulated activation of ERK1/2 is regulated by the ASK1-p38 MAPK pathway. 相似文献
948.
Tsuchiya K Murayama S Mitani K Oda T Arima K Mimura M Nagura H Haga C Akiyama H Yamanouchi H Mizusawa H 《Acta neuropathologica》2005,109(4):353-366
This report concerns a clinicopathological study of three additional patients with corticobasal degeneration (CBD), described here for the first time, and a clinicopathological correlation between pyramidal signs and upper motor neuron involvement, in ten autopsy cases of CBD, including seven cases reported by us previously. We investigated pyramidal signs, including hyperreflexia, Babinski sign, and spasticity, and involvement of the primary motor cortex and pyramidal tract, focusing on the astrocytosis of the fifth layer of the primary motor cortex. Pyramidal signs were observed in six (60%) of the ten cases. Hyperreflexia was evident in six patients (60%), with spasticity being observed in three patients (30%). Loss of Betz cells associated with prominent astrocytosis and presence of ballooned neurons in the fifth layer of the primary motor cortex was observed in all ten cases. In all cases, involvement of the pyramidal tract was obvious in the medulla oblongata, without involvement of the pyramidal tract in the midbrain. Constant and severe involvement of the fifth layer of the primary motor cortex, including the Betz cells, has not previously been reported in CBD. We suggest that the pyramidal signs in CBD have been disregarded. 相似文献
949.
The effectiveness of the automated motion correction software (INSTILL, Philips Medical Systems Co. Ltd., Andover, USA) proposed by Matsumoto et al. to prevent motion artifact in quantitative gated SPECT, was tested with a technetium-99m point source and cardiac phantom. INSTILL well corrected the error due to point source movement during acquisition up to a distance of 5 pixels (32.8 mm) in the right and caudal directions, as well as with a distance of up to 7 pixels (45.9 mm) of oblique (caudal-right 45 degree) movement inside the coronal plane. End-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were also well adjusted with INSTILL, for up to 3 pixels (19.7 mm) movement of the dynamic cardiac phantom during acquisition in the right, caudal and oblique directions. The respective maximum error with one, two and three pixel movement was 9, 24 and 23 ml in EDV, and 8, 22 and 21 ml in ESV. The maximum error of EF was 3% in all conditions without INSTILL. After using INSTILL, the maximum residual errors of both EDV and ESV were 7 ml and that of EF was 3% in all conditions. Quantitative gated SPECT software with INSTILL will calculate EDV, ESV and EF against movement of patients in the coronal plane. INSTILL is therefore concluded to be a reliable software for motion correction in clinical use. 相似文献
950.
Extraosseous accumulation of99mTc-HMDP to radiation nephropathy, mimicking recurrent neuroblastoma 总被引:1,自引:0,他引:1
Abe K Sasaki M Kuwabara Y Koga H Baba S Kaneko K Hayashi K Shioyama Y Tajiri T Suita S Honda H 《Annals of nuclear medicine》2005,19(1):35-40
OBJECTIVE: The aim of this study is to clarify the period of extraosseous accumulation of (99m)Tc-hydroxymethylenediphosphonate (HMDP) to radiation nephropathy mimicking recurrent or remnant neuroblastoma in the pararenal region. METHODS: We reviewed five neuroblastoma and one ganglioneuroblastoma patients (2 boys and 4 girls aged 1-9 years) who underwent (99m)Tc-HMDP bone scintigraphies periodically before and after radiation therapy. RESULTS: Increased renal uptake coincident with the radiation port appeared in 5 of 6 patients from 0 to 3 months (mean 1.7 months), and persisted up to 7 months after the completion of radiotherapy. Renal uptake of (99m)Tc-HMDP was gradually decreased, and eventually became accumulation defects in 5 of 6 patients from 6 to 17 months (mean 8.9 months) after radiotherapy. CONCLUSION: When extraosseous accumulation is found after radiation therapy in neuroblastoma patients, radiation nephropathy would be a candidate in the differential diagnosis besides recurrent or remnant tumor. 相似文献