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991.
A. Kanazawa Azumi Tozuka Sumie Kato Tetsuo Mikami J. Abe Yoshiya Shimamoto 《Current genetics》1998,33(3):188-198
Mitochondrial DNA (mtDNA) fragments that contain cox2 and atp6 were cloned from a wild soybean (Glycine soja, accession `B09002') and from a cultivated soybean (G. max, `Harosoy'). Comparison of these DNAs revealed that two sets of repeated sequences, namely, 299 bp and 23 bp, were present
in the 5′ regions of cox2 and atp6. The 299-bp and 23-bp repeats were present close to each other on the 5′ flanking region and the 5′ part of the coding region
of cox2 in both `Harosoy' and `B09002', as well as on the 5′ flanking region of atp6 in `Harosoy', while these two repeats were separated by a 706-bp nucleotide sequence that contained a truncated sequence
of nad3 at the 5′ flanking region of atp6 in `B09002'. The mtDNA configurations upstream from atp6 and cox2 found in `Harosoy' appeared to have been generated from configurations of cox2 and atp6 found in `B09002' via recombination across the 299-bp or 23-bp repeated sequences, or vice versa, in the mitochondrial genome
of the hypothetical progenitor of these plants. The 299-bp sequence was found to be interspersed in the mitochondrial genome.
Eight loci were identified that include mtDNA configurations that are inter-convertible with each other via recombination
across this sequence in `B09002'. Various loci on the mitochondrial genomes of higher plants that harbor segments of the 299-bp
repeats in Glycine were identified.
Received: 16 August / 15 December 1997 相似文献
992.
993.
Detection of Bartonella quintana from body lice (Anoplura: Pediculidae) infesting homeless people in Tokyo by molecular technique 总被引:13,自引:0,他引:13
We report detection of Bartonella quintana Brenner, the pathogenic agent of trench fever, from body lice, Pediculus humanus L., infesting homeless people in Tokyo by polymerase chain reaction. Two of 12 (16.7%) homeless were infested with Bartonella-positive body lice. From the current status of the recent increase of homeless people in many large cities of the developed countries, a medical examination of homeless people should be carefully performed in the consideration of trench fever. Sampling of body lice from clothing of homeless people is recommended for quick and accurate diagnosis of trench fever through the detection of B. quintana DNA. 相似文献
994.
Nakamura T Ushiyama C Suzuki Y Shoji H Shimada N Koide H 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(3):244-248
We investigated whether microalbuminuria/urinary creatinine ratio (MACR) is increased in septic patients with trauma and whether polymyxin B immobilized fiber (PMX-F) treatment decreases MACR. Twelve trauma patients without sepsis, 18 trauma patients with sepsis, and 10 healthy controls were included in this study. The 18 trauma patients with sepsis were randomly assigned to one of two groups, PMX-F treatment or conventional treatment. Urinary microalbumin and creatinine were measured before and after treatment. Plasma endotoxin levels were determined by endospecy test. Hemoperfusion with PMX-F was carried out twice, for 2 hours, at a flow rate of 100 ml/min. MACR increased in the 30 trauma patients (5.2+/-2.2 mg/mmol) in comparison to that in the healthy controls (1.0+/-0.6 mg/mmol, p < 0.01). In the 18 trauma patients with sepsis, MACR after sepsis (16.6+/-4.8 mg/mmol) was significantly greater than that before sepsis (5.5+/-2.3 mg/mmol, p < 0.01). There was a significant correlation between plasma endotoxin levels and MACR in septic trauma patients (p < 0.001). MACR was reduced from 17.0+/-5.0 mg/mmol to 4.2+/-1.5 mg/mmol (p < 0.01) with PMX-F, and plasma endotoxin levels were also reduced from 34.5+/-18.5 pg/ml to 10.8+/-6.6 pg/ml (p < 0.01). Neither MACR nor plasma endotoxin levels were affected by conventional treatment, however. In summary, trauma patients with sepsis appear to show increased MACR, and PMX-F therapy may be effective for attenuating the increase in MACR. 相似文献
995.
Beta2-adrenergic receptor stimulation inhibits LPS-induced IL-18 and IL-12 production in monocytes 总被引:1,自引:0,他引:1
Mizuno K Takahashi HK Iwagaki H Katsuno G Kamurul HA Ohtani S Mori S Yoshino T Nishibori M Tanaka N 《Immunology letters》2005,101(2):168-172
We examined the effects of beta2-adrenergic receptor (beta2-AR) agonists on monocyte-derived cytokines, interleukin (IL)-18 and IL-12 production in lipopolysaccharide (LPS)-stimulated monocytes derived from human peripheral blood mononuclear cells (PBMCs), as in vitro model of sepsis. The study found that beta2-AR agonists inhibited IL-18 and IL-12 production in monocytes, and that AR agonist activity was antagonized by the selective beta2-AR antagonist, butoxamine. The selective beta2-AR agonists salbutamol and terbutaline induced a similar inhibitory pattern of IL-18 and IL-12 production. IL-12 production induced by LPS was inhibited by anti-IL-18 Ab, but IL-18 production by LPS was not inhibited by anti-IL-12 Ab, showing that LPS induced IL-18 production without IL-12 production. Therefore, the stimulation of beta2-AR might be beneficial in the treatment of sepsis through inhibiting LPS-elicited IL-18. 相似文献
996.
Tomoyuki Yamashita Noriaki Kameda Kenji Katayama Nobuyuki Hiruta Masahiro Nakada Yasushi Takeda 《Pathology international》1990,40(2):137-142
A case of true malignant mixed tumor of the submandibular gland is reported. The submandibular tumor, occurring in a 52-year-old man, started to grow rapidly after a long history without any change in size. Surgical resection was carried out and the resected tumor measured 5.5 cm with a cut surface showing mixed solid structures. Microscopically, the tumor had both carcinomatous and sarcomatous elements, the former consisting of poorly differentiated adenocarcinoma with squamous cell differentiation and the latter consisting of osteosarcoma with chondrosarcomatous and fibrosarcomatous elements. A remnant of benign pleomorphic adenoma could also be identified. Immunohistochemical study demonstrated keratin and epithelial membrane antigen in the carcinoma cells and vimentin in all elements of the osteosarcoma. It is assumed from these clinical and histological findings that the tumor had transformed from a pre-existing benign pleomorphic adenoma. Acta Pathol Jpn 40: 137–142, 1990. 相似文献
997.
Keiko Nagano Jun Nakura Koichi Kihara Lin Ye Kouzin Kamino Noriaki Mitsuda Tohru Ohta Yoshihiro Jinno Norio Niikawa Tetsuro Miki Toshio Ogihara 《Journal of human genetics》1993,38(4):391-397
Summary We have constructed a new genetic linkage map of the Werner syndrome (WRN) region, using microsatellites from a library which was developed by a chromosome microdissection and enzymatic amplification method. These microsatellites were used to genotype members of CEPH families using a simplified detection system of polymerase chain reaction (PCR) products. Two-point analysis was used to assign 4 microsatellite markers relative to each marker and other markers reported in the CEPH public data base. We confirmed that these 4 markers are located to the WRN region, 8p11.2–p22. Such microsatellites microdissected from the definite chromosome region may be useful for positional cloning. 相似文献
998.
Recent progress in the study of chromogranins has revealed that there are many novel peptides derived from chromogranin with
their multiple pathophysiologic roles. To learn the possible roles of chromogranin in breast carcinoma, we immunohistochemically
investigated tissue localization of chromogranin A (CgA) and chromogranin B (CgB) in 10 normal breast tissues, 23 noninvasive
ductal carcinomas (NIDCs), and 169 invasive ductal carcinomas (IDCs) and compared their expression with estrogen receptor
(ER), progesterone receptor (PR), and Ki67. CgA and CgB were sporadically detected in normal cells of the ducts, acini, and
luminal secretion. The expression of CgA and CgB was higher in NIDCs than in IDCs: CgA=70% of NIDC vs 22% of IDC and CgB=65%
of NIDC vs 30% of IDC. There was a statistical correlation between the expression of CgA and PR (p < 0.05) and CgB and ER (p < 0.05) in IDCs without lymph node metastasis. On the other hand, there was a significant correlation between expression
of CgB and PR and an inverse correlation between CgA and Ki67 in IDCs of overall cases. The data suggest that CgA and CgB
may play some role in the early phase of neoplastic progression. 相似文献
999.
1000.
Takaki Shimizu Satoru Demura Satoshi Kato Kazuya Shinmura Noriaki Yokogawa Noritaka Yonezawa Norihiro Oku Ryo Kitagawa Makoto Handa Ryohei Annen Takayuki Nojima Hideki Murakami Hiroyuki Tsuchiya 《Clinical orthopaedics and related research》2021,479(1):163
BackgroundRecent advances in multidisciplinary treatments for various cancers have extended the survival period of patients with spinal metastases. Radiotherapy has been widely used to treat spinal metastases; nevertheless, long-term survivors sometimes undergo more surgical intervention after radiotherapy because of local tumor relapse. Generally, intradural invasion of a spinal tumor seldom occurs because the dura mater serves as a tissue barrier against tumor infiltration. However, after radiation exposure, some spinal tumors invade the dura mater, resulting in leptomeningeal dissemination, intraoperative dural injury, or postoperative local recurrence. The mechanisms of how radiation might affect the dura have not been well-studied.Questions/purposesTo investigate how radiation affects the spinal meninges, we asked: (1) What is the effect of irradiation on the meningeal barrier’s ability to protect against carcinoma infiltration? (2) What is the effect of irradiation on the meningeal barrier’s ability to protect against sarcoma infiltration? (3) What is the effect of irradiation on dural microstructure observed by scanning electron microscopy (SEM)? (4) What is the effect of irradiation on dural microstructure observed by transmission electron microscopy (TEM)?MethodsEighty-four 10-week-old female ddY mice were randomly divided into eight groups: mouse mammary tumor (MMT) implantation 6 weeks after 0-Gy irradiation (nonirradiation) (n = 11), MMT implantation 6 weeks after 20-Gy irradiation (n = 10), MMT implantation 12 weeks after nonirradiation (n = 10), MMT implantation 12 weeks after 20-Gy irradiation (n = 11), mouse osteosarcoma (LM8) implantation 6 weeks after nonirradiation (n = 11), LM8 implantation 6 weeks after 20-Gy irradiation (n = 11), LM8 implantation 12 weeks after nonirradiation (n = 10), and LM8 implantation 12 weeks after 20-Gy irradiation (n = 10); female mice were used for a mammary tumor metastasis model and ddY mice, a closed-colony mice with genetic diversity, were selected to represent interhuman diversity. Mice in each group underwent surgery to generate a tumor-induced spinal cord compression model at either 6 weeks or 12 weeks after irradiation to assess changes in the meningeal barrier’s ability to protect against tumor infiltration. During surgery, the mice were implanted with MMT (representative of a carcinoma) or LM8 tumor. When the mice became paraplegic because of spinal cord compression by the growing implanted tumor, they were euthanized and evaluated histologically. Four mice died from anesthesia and 10 mice per group were euthanized (MMT-implanted groups: MMT implantation occurred 6 weeks after nonirradiation [n = 10], 6 weeks after irradiation [n = 10], 12 weeks after nonirradiation [n = 10], and 12 weeks after irradiation [n = 10]; LM8-implanted groups: LM8 implantation performed 6 weeks after nonirradiation [n = 10], 6 weeks after irradiation [n = 10], 12 weeks after nonirradiation [n = 10], and 12 weeks after irradiation [n = 10]); 80 mice were evaluated. The spines of the euthanized mice were harvested; hematoxylin and eosin staining and Masson’s trichrome staining slides were prepared for histologic assessment of each specimen. In the histologic assessment, intradural invasion of the implanted tumor was graded in each group by three observers blinded to the type of tumor, presence of irradiation, and the timing of the surgery. Grade 0 was defined as no intradural invasion with intact dura mater, Grade 1 was defined as intradural invasion with linear dural continuity, and Grade 2 was defined as intradural invasion with disruption of the dural continuity. Additionally, we euthanized 12 mice for a microstructural analysis of dura mater changes by two observers blinded to the presence of irradiation. Six mice (three mice in the 12 weeks after nonirradiation group and three mice in the 12 weeks after 20-Gy irradiation group) were quantitatively analyzed for defects on the dural surface with SEM. The other six mice (three mice in the 12 weeks after nonirradiation group and three mice in the 12 weeks after 20-Gy irradiation group) were analyzed for layer structure of collagen fibers constituting dura mater by TEM. In the SEM assessment, the number and size of defects on the dural surface on images (200 μm × 300 μm) at low magnification (× 2680) were evaluated. A total of 12 images (two per mouse) were evaluated for this assessment. The days from surgery to paraplegia were compared between each of the tumor groups using the Kruskal-Wallis test. The scores of intradural tumor invasion grades and the number of defects on dural surface per SEM image were compared between irradiation group and nonirradiation group using the Mann-Whitney U test. Interobserver reliabilities of assessing intradural tumor invasion grades and the number of dural defects on the dural surface were analyzed using Fleiss’κ coefficient. P values < 0.05 were considered statistically significant.ResultsThere was no difference in the median (range) time to paraplegia among the MMT implantation 6 weeks after nonirradiation group, the 6 weeks after irradiation group, the 12 weeks after nonirradiation group, and the 12 weeks after irradiation group (16 days [14 to 17] versus 14 days [12 to 18] versus 16 days [14 to 17] versus 14 days [12 to 15]; χ2 = 4.7; p = 0.19). There was also no difference in the intradural invasion score between the MMT implantation 6 weeks after irradiation group and the 6 weeks after nonirradiation group (8 of 10 Grade 0 and 2 of 10 Grade 1 versus 10 of 10 Grade 0; p = 0.17). On the other hand, there was a higher intradural invasion score in the MMT implantation 12 weeks after irradiation group than the 12 weeks after nonirradiation group (5 of 10 Grade 0, 3 of 10 Grade 1 and 2 of 10 Grade 2 versus 10 of 10 Grade 0; p = 0.02). Interobserver reliability of assessing intradural tumor invasion grades in the MMT-implanted group was 0.94. There was no difference in the median (range) time to paraplegia among in the LM8 implantation 6 weeks after nonirradiation group, the 6 weeks after irradiation group, the 12 weeks after nonirradiation group, and the 12 weeks after irradiation group (12 days [9 to 13] versus 10 days [8 to 13] versus 11 days [8 to 13] versus 9 days [6 to 12]; χ2 = 2.4; p = 0.50). There was also no difference in the intradural invasion score between the LM8 implantation 6 weeks after irradiation group and the 6 weeks after nonirradiation group (7 of 10 Grade 0, 1 of 10 Grade 1 and 2 of 10 Grade 2 versus 8 of 10 Grade 0 and 2 of 10 Grade 1; p = 0.51), whereas there was a higher intradural invasion score in the LM8 implantation 12 weeks after irradiation group than the 12 weeks after nonirradiation group (3 of 10 Grade 0, 3 of 10 Grade 1 and 4 of 10 Grade 2 versus 8 of 10 Grade 0 and 2 of 10 Grade 1; p = 0.04). Interobserver reliability of assessing intradural tumor invasion grades in the LM8-implanted group was 0.93. In the microstructural analysis of the dura mater using SEM, irradiated mice had small defects on the dural surface at low magnification and degeneration of collagen fibers at high magnification. The median (range) number of defects on the dural surface per image in the irradiated mice was larger than that of nonirradiated mice (2 [1 to 3] versus 0; difference of medians, 2/image; p = 0.002) and the median size of defects was 60 μm (30 to 80). Interobserver reliability of assessing number of defects on the dural surface was 1.00. TEM revealed that nonirradiated mice demonstrated well-organized, multilayer structures, while irradiated mice demonstrated irregularly layered structures at low magnification. At high magnification, well-ordered cross-sections of collagen fibers were observed in the nonirradiated mice. However, disordered alignment of collagen fibers was observed in irradiated mice.ConclusionIntradural tumor invasion and disruptions of the dural microstructure were observed in the meninges of mice after irradiation, indicating radiation-induced disruption of the meningeal barrier.Clinical RelevanceWe conclude that in this form of delivery, radiation is associated with disruption of the dural meningeal barrier, indicating a need to consider methods to avoid or limit Postradiation tumor relapse and spinal cord compression when treating spinal metastases so that patients do not experience intradural tumor invasion. Surgeons should be aware of the potential for intradural tumor invasion when they perform post-irradiation spinal surgery to minimize the risks for intraoperative dural injury and spinal cord injury. Further research in patients with irradiated spinal metastases is necessary to confirm that the same findings are observed in humans and to seek irradiation methods that prevent or minimize the disruption of meningeal barrier function. 相似文献