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41.
Maekawa M; Sugano K; Kashiwabara H; Ushiama M; Fujita S; Ohkura H; Kakizoe T 《Japanese journal of clinical oncology》1998,28(6):383-387
BACKGROUND: Ornithine decarboxylase (ODC; EC 4.1.1.17) is the first
rate-limiting enzyme in the biosynthesis of polyamines. ODC protein has a
characteristic amino acid sequence, the PEST sequence, which is related to
the enzyme's rapid degradation. ODC cDNA prepared from human hepatoma
tissues has been reported to show nonsense or missense mutations. METHODS:
We examined somatic mutations of ODC cDNA by RT-PCR-SSCP analysis and mRNA
expressions by RT-PCR in 50 colorectal cancer tissues to investigate the
involvement of ODC gene alterations in colorectal cancers. RESULTS:
Increased expression of the ODC gene was observed in 36 cases (86%) out of
the 42 examined by RT-PCR. In one case, a missense mutation was found in
the cancer tissue but not in normal mucosa. The missense mutation from Asp
to Asn at codon 424, in the PEST region, possibly stabilizes the ODC
protein. In colorectal cancer, replication error and a germline mutation in
hMSH2 gene were observed. CONCLUSIONS: The missense mutation at codon 424
is speculated to be a cause of stabilization and a passenger mutation owing
to the mutator phenotype. Since only one of 50 colorectal cancers exhibited
a missense mutation of the ODC gene, mutations in ODC gene are not frequent
in colorectal cancer. The increased expression of the ODC gene was noted in
86% of colorectal cancer tissues by RT-PCR, however, it was not due to
point mutations in ODC coding exons.
相似文献
42.
43.
Objective: To report four cases of rice bodies (RBs) showing remarkable size variations and discuss their pathogenesis.
Design and patients: Based on analysis of the clinical data, we speculate on the pathogenesis of RBs using immunohistochemical and ultrastructural
methods. The patients comprised three men and one woman, three with RBs in the subacromial bursae and one in the wrist synovial
sheath, aged 28 (woman), 44, 50 and 81 (wrist) years, respectively.
Results: There were no particular differences in clinical data among the patients. T2-weighted MR imaging was very useful for diagnosis
of the RBs, allowing their clear delineation from the bursal fluid. The RBs consisted of a layered protein- aceous substance
with vague targetoid cut surfaces. Much fibrin and a lesser amount of collagen fibers were recognized together with various
mononuclear cells, which were few in number and predominantly T cells. The bursae and synovial sheath had multiple fibrinoid
spheroids at the luminal surface. Conclusion: Fibrinoid nodular deposits probably became detached, forming the nuclei of RBs and growing to a giant RB 65 mm in diameter.
Received: 27 September 1999 Revision requested: 5 January 2000, 21 March 2000 Revision received: 21 March 2000, 14 April 2000
Accepted: 8 June 2000 相似文献
44.
Saburo Omata Kenji Sakimura Hidemi Tsubaki Hiroshi Sugano 《Toxicology and applied pharmacology》1978,44(2):367-378
Rats were given daily sc injections of methylmercury chloride, 10 mg/kg for 7 consecutive days. The manifestation of the neurological syndrome in the rat and the accumulation of mercury in rat tissues resembled the observations of previous investigators. The incorporation in vitro of [14C]leucine into brain protein began to decrease during the latent period of intoxication and declined to 56% of the control values at the symptomatic period. The incorporation of [14C]leucine into liver protein was also inhibited to a similar extent at the symptomatic period following a remarkable stimulation at the early stage after the onset of administration of methylmercury. The impairment of protein synthesis in the brain and liver at the symptomatic period was confirmed by the incorporation in vivo of a 14C-labeled amino acid mixture into proteins of these tissues. The decrease in the [14C]leucine incorporation in the liver of poisoned rats was largely affected by nutritional deficiency due to decreased food intake, but that in the brain resulted from the direct effect of methylmercury on this tissue. 相似文献
45.
Naofumi Ikeda Toshihide Hayashi Shikou Gen Nobuhiko Joki Kazuhiko Aramaki 《Renal failure》2022,44(1):1098
PurposeTo determine the location of coronary atherosclerosis distribution observed in patients with chronic kidney disease (CKD).MethodsA cross-sectional study was conducted using the database of cardiovascular medicine data from Saitama Sekishinkai Hospital to clarify the association between renal function and angiographic characteristics of coronary atherosclerosis. In total, 3268 patients who underwent percutaneous coronary intervention were included. Propensity score matching revised the total to 1772. The association of renal function with the location and/or distribution of coronary atherosclerosis lesions was then examined.ResultsOverall, coronary lesion was observed in the left anterior descending coronary artery (LAD) in 56% patients, whereas 28% and 22% were in the right coronary artery (RCA) and left circumflex coronary artery (LCX), respectively. LAD was most affected and observed in 57% patients with stage 1 CKD. RCA was second-most affected, at 26% CKD stage 1, but it increased to 31%, 38%, and 59% in CKD 3, 4, and 5, respectively. In CKD 5 patients, the RCA was the most affected artery (59%), with 41% LAD lesions. Logistic regression analysis after propensity score matching showed that the odds ratios for an RCA lesion was 3.658 in CKD 5 (p = .025) compared with CKD 1 after adjusting for traditional risk factors.ConclusionThe prevalence of RCA lesions, but not LAD or LCX lesions, increased with increasing CKD stage. The pathophysiology of coronary atherosclerosis may differ by lesion location. Deterioration of renal function may affect progression of atherosclerosis more in the RCA than in the LAD or LCX. 相似文献
46.
Mao Hagihara Hideo Kato Toshie Sugano Hayato Okade Nobuo Sato Yuichi Shibata Daisuke Sakanashi Nobuhiro Asai Yusuke Koizumi Hiroyuki Suematsu Yuka Yamagishi Hiroshige Mikamo 《International journal of antimicrobial agents》2021,57(5):106330
BackgroundCarbapenem-resistant Enterobacterales (CRE) and carbapenemase-producing Enterobacterales (CPE) are difficult to treat and are a serious public health threat. Nacubactam (NAC) is a novel non-β-lactam diazabicyclooctane β-lactamase inhibitor with in vitro activity against some Enterobacterales expressing classes of β-lactamases.MethodsThe antimicrobial efficacy of meropenem (MEM), cefepime (FEP), and aztreonam (ATM), each in combination with NAC, were assessed in vitro and in vivo against Klebsiella pneumoniae and Escherichia coli. Ten isolates, including CRE and/or CPE with β-lactamase genes, were used in this study. The relationship between phenotype and in vivo efficacy was assessed in a murine neutropenic thigh-infection model. Efficacy was determined by the change in bacterial quantity.ResultsThe results of the in vitro study showed the minimum inhibitory concentrations of the combination of NAC with either MEM, FEP, or ATM in a 1:1 ratio were 2 to >128-fold lower than those of MEM, FEP, or ATM alone against CRE+ isolates. In addition, combinations of β-lactams and NAC administered in the murine thigh-infection model showed greater efficacy against CRE+/CPE+, CRE+/CPE-, and CRE-/CPE+ isolates harboring various β-lactamase genes (IMP-1, IMP-6, KPC, DHA-1, or OXA-48) compared with MEM, FEP, ATM, and NAC alone.ConclusionMEM, FEP, or ATM in combination with NAC showed potent in vivo antimicrobial activity in a murine thigh-infection model caused by K. pneumoniae and E. coli, including CRE and/or CPE isolates. These findings indicate that these combinations of β-lactams and NAC are potential candidates for the treatment of CRE and/or CPE infections. 相似文献
47.
Hiroshi MIYABAYASHI Nobuhiko NAGANO Risa KATO Takanori NOTO Shin HASHIMOTO Katsuya SAITO Ichiro MORIOKA 《Neurologia medico-chirurgica》2022,62(5):246
Currently, molded helmet therapy is used to treat infants with deformational plagiocephaly. However, the indices of normal cranial shape remain unclear, and thus, the prevalence of deformational plagiocephaly is unknown, particularly in Japan. We investigated the reference values for cranial morphological characteristics in 1-month-old Japanese infants using a three-dimensional scanner, to determine the prevalence of deformational plagiocephaly. One hundred fifty-three healthy infants who visited three hospitals (from April 2020 to March 2021) were enrolled. Cranial shape was measured using a three-dimensional scanner and was analyzed using image analysis software. Outcome measures were cranial volume, length, width, length-width ratio, circumference, asymmetry, and vault asymmetry index; cephalic index; and anterior, posterior, and overall symmetry ratios. The cranial vault asymmetry index >3.5% or ≥10% were diagnosed as deformational or severe deformational plagiocephaly, respectively. The mean age at measurement was 35.7 days. The mean cranial volume was 559 mL; cranial length, 129 mm; cranial width, 110 mm; length-width ratio, 118%; cephalic index, 85.2%; cranial circumference, 377 mm, cranial asymmetry, 6.4 mm; cranial vault asymmetry index, 5.0%; and anterior, posterior, and overall asymmetry ratios, 93.1%, 91.3%, and 96.4%, respectively. The prevalence of deformational and severe deformational plagiocephaly was 64.7% and 6.6%, respectively. Sex-based differences were observed for cranial volume and width. The results obtained in this study can be considered standard values that can facilitate the differentiation of abnormal infant cranial morphological characteristics for Japanese medical practitioners. 相似文献
48.
Tomoko Akahane Kenta Masuda Akira Hirasawa Yusuke Kobayashi Arisa Ueki Miho Kawaida Kumiko Misu Kohei Nakamura Shimpei Nagai Tatsuyuki Chiyoda Wataru Yamagami Shigenori Hayashi Fumio Kataoka Kouji Banno Kokichi Sugano Hajime Okita Kenjiro Kosaki Hiroshi Nishihara Daisuke Aoki 《Journal Of Gynecologic Oncology》2022,33(4)
ObjectivePrecursor lesions may be identified in fallopian tube tissue after risk-reducing salpingo-oophorectomy (RRSO) in patients with pathogenic variants of BRCA1/2. Serous tubal intraepithelial carcinoma (STIC) is considered a precursor of high-grade serous carcinoma, whereas the significance of the p53 signature remains unclear. In this study, we investigated the relationship between the p53 signature and the risk of ovarian cancer.MethodsWe analyzed the clinicopathological findings and conducted DNA sequencing for TP53 variants of p53 signatures and STIC lesions isolated using laser capture microdissection in 13 patients with pathogenic variants of BRCA1/2 who underwent RRSO and 17 control patients with the benign gynecologic disease.Results TP53 pathogenic variants were detected significantly higher in RRSO group than control (p<0.001). No difference in the frequency of p53 signatures were observed between groups (53.8% vs 29.4%; p=0.17). TP53 sequencing and next-generation sequencing analysis in a patient with STIC and occult cancer revealed 2 TP53 mutations causing different p53 staining for STICs and another TP53 mutation shared between STIC and occult cancer.ConclusionThe sequence analysis for TP53 revealed 2 types of p53 signatures, one with a risk of progression to STIC and ovarian cancer with pathological variants in TP53 and the other with a low risk of progression without pathological variants in TP53 as seen in control. 相似文献
49.
Yoshida H Mamada Y Taniai N Mizuguchi Y Kakinuma D Ishikawa Y Kanda T Matsumoto S Bando K Akimaru K Tajiri T 《Journal of Hepato-Biliary-Pancreatic Surgery》2008,15(2):178-182
Background/Purpose According to the General rules for the clinical and pathological study of primary liver cancer, compiled by the Liver Cancer Study Group of Japan, ruptured hepatocellular carcinoma (HCC) is classified as stage 4, even
if the tumor is small and solitary. We examined the long-term results of elective hepatectomy for the treatment of ruptured
HCC.
Methods A first hepatectomy was performed without operative death in 193 patients with HCC. Ten patients had ruptured HCC (ruptured
group) and 183 patients had nonruptured HCC (nonruptured group). The extension of HCC was macroscopically classified as stage
1 in 23 patients, stage 2 in 71, stage 3 in 53, and stage 4 in 46.
Results Cumulative survival rates in the ruptured group at 1, 5, and 10 years were 90.0%, 67.5%, and 20.3%, respectively. The cumulative
survival rate was lower in patients with stage 4 disease in the nonruptured group than that in patients in the ruptured group
(P < 0.05). Cumulative survival rates did not differ significantly between patients in the ruptured group and those with stage
2 or stage 3 disease.
Conclusions Survival rates after elective hepatectomy in patients with ruptured HCC are good, even if the disease is classified as stage
4. 相似文献
50.