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21.
Tatsuo Uchida Takahiko Tokumaru Hiroshi Kojima Katsura Nakagawaji Munehisa Imaizumi Toshio Abe 《Surgery today》1992,22(3):265-268
A 36 year old woman was admitted to our department because of a chest X-ray which showed multiple developing shadows. She underwent bilateral exploratory thoracotomies and a total 5 tumors were resected and pathologically diagnosed as benign metastasizing leiomyoma, the largest of which was positive for the progesterone receptor and negative for the estrogen receptor. A histogram of this tumor using a flow cytometer showed a diploid pattern and 4.6 percent of the S phase which was not more than that of a leiomyoma of the uterus from another patient. Two months later, she underwent a hysterectomy and bilateral salpingo-oophorectomy for treatment of the positive progesterone receptor in the pulmonary lesions. The resected uterine myoma and normal myometrium showed positive estrogen and progesterone receptors. For the subsequent 28 months she has been free of any further symptoms. Benign metastasizing leiomyoma of the uterus is a rare disease and very interesting because of its histological benignity and hormonal dependency. However, according to the literature, it is often confused in entity due to the fact that normal lung tissue also possesses hormone receptors. Considering our data on hormone receptors, it is rational to think that multiple leiomyomatous lesions in the lung should only be diagnosed as benign metastasizing leiomyomas when they possess positive estrogen and progesterone receptors. 相似文献
22.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献
23.
A 28-year-old woman had developed chronic, recurrent, visual disturbance (bilateral), and girdle sensation at Th 5-6. She was admitted to our hospital because of left visual disturbance, distal limb weakness on right side, and numbness of four extremities. The neurological examination revealed decreased visual acuity of the left eye with abnormality of the optic disk, moderate muscle weakness of the right upper and lower extremities, absent tendon reflexes and paresthesia on distal portions of the four limbs. Laboratory examinations disclosed the titration of anti-myelin associated glycoprotein (MAG) antibody (IgM) and CSF protein was elevated (104 mg/dl). Motor nerve conduction studies revealed conduction block in more than one nerve. The conduction velocities in the upper and lower extremities were all diminished. P100 latency was prolonged by flash visual evoked potential (VEP) studies. N13-N20 interpeak latency of somatosensory evoked potential (SEP) of median nerve was also prolonged. She was treated with steroid pulse therapy, followed by an oral dose of 30 mg/day of prednisolone. Her symptoms resolved completely three months later, and multifocal conduction block subsided on electrophysiological study. There are some cases of multiple sclerosis with multifocal conduction block, but such a case is very rare in Japan. We discussed the pathogenic mechanisms of these conditions, and we conclude that we must take notice of demyelinating neuropathy in multiple sclerosis and that nerve conduction studies are useful for detecting them. 相似文献
24.
Effects of flunarizine therapy on intractable epilepsy 总被引:2,自引:0,他引:2
In an open trial the antiepileptic effects of flunarizine were studied in 64 patients with intractable epilepsy, and the following results were obtained: 1. Seizures disappeared completely in 2 cases, with a 50% decrease in 6 cases. 2. Of the 25 patients who had accompanying psychiatric symptoms 8.0% showed an improvement in these symptoms. 3. While no marked side-effects were observed, some cases showed an increase in frequency of seizures and the trial was stopped for 8 cases. 4. "Global evaluation" showed an overall improvement rate of 9.4%. In 47 cases, in which changes in frequency of seizure were confirmed and dosage of flunarizine was subsequently changed, improvement rate was 12.8%. 5. The above results suggest that the effectiveness of flunarizine in this open trial was very low. 相似文献
25.
26.
Protective Role of Nitric Oxide in Staphylococcus aureus Infection in Mice 总被引:6,自引:0,他引:6
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Sanae Sasaki Tomisato Miura Shinsuke Nishikawa Kyogo Yamada Mayuko Hirasue Akio Nakane 《Infection and immunity》1998,66(3):1017-1022
This study was carried out to determine the role of nitric oxide (NO) in Staphylococcus aureus infection in mice. NO production in spleen cell cultures was induced by heat-killed S. aureus. Expression of mRNA of the inducible isoform of NO synthase (iNOS) was induced in the spleens and kidneys of S. aureus-infected mice. When mice were treated with monoclonal antibodies (MAbs) against tumor necrosis factor alpha (TNF-α) or gamma interferon (IFN-γ) before S. aureus infection, the induction of iNOS mRNA expression in the kidneys was inhibited. These MAbs also inhibited NO production in spleen cell cultures stimulated with heat-killed S. aureus. NO production in the spleen cell cultures and levels of urinary nitrate plus nitrite were suppressed by treatment with aminoguanidine (AG), a selective inhibitor of iNOS. The survival rates of AG-treated mice were significantly decreased by either lethal or sublethal S. aureus infections. However, an effect of AG administration on bacterial growth was not observed in the spleens and kidneys of mice during either type of infection. Production of TNF-α and IFN-γ was not affected by AG treatment in vitro and in vivo. These results suggest that NO plays an important role in protection from lethality by the infection, but the protective role of NO in host resistance against S. aureus infection was not proved. Moreover, our results show that TNF-α and IFN-γ regulate NO production while NO may not be involved in the regulation of the production of these cytokines during S. aureus infection. 相似文献
27.
Kawano S Morotomi T Toyono T Nakamura N Uchida T Ohishi M Toyoshima K Harada H 《Connective tissue research》2002,43(2-3):409-412
Rat incisors grow continuously throughout life. Producing a variety of dental epithelial cells is performed by stem cells located in the cervical loop of the incisor apex. To study the mechanisms for cell differentiation, we established a dental epithelial cell line (HAT-7) originating from a cervical loop epithelium of a rat incisor. Immunochemical studies showed that HAT-7 produced the cells expressing amelogenin, ameloblastin, or alkaline phosphatase (ALP). To illustrate a role of Notch signaling in the determinant of the cell fate, we examined expression patterns of Notch1 and Jagged1 in HAT-7 density dependently. At lower cell density, Notch1- or Jagged1-expressing cells were not seen. However, when they were fully confluent, cells began to express Notch1 or Jagged1 strongly. Some ALP-positive cells were almost consistent with Notch1-expressing cells but not Jagged1-expressing cells. These results suggested that the determinant of direction of differentiation was associated with Notch signaling pathway. 相似文献
28.
Takahiko Hara Masatake Yamauchi Ei-ichi Takahashi Masato Hoshino Kazuhisa Aoki Dai Ayusawa Masao Kawakita 《Somatic Cell and Molecular Genetics》1993,19(6):571-575
We have cloned a segment of the human gene encoding UDP-galactose translocator by genetic complementation of its defective mutant in mouse FM3A cells. Chromosome mapping using fluorescentin situ hybridization revealed that the cloned gene hybridized to the Xp11.23-11.23 region of the X chromosome. This region is shared by the locus of Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency disorder, characterized by defective sugar chains on cell surface components. Genetic and phenotypic similarities suggest a possible link between UDP-galactose translocator and the Wiskott-Aldrich syndrome (WAS). 相似文献
29.
Transforming growth factor beta is protective in host resistance against Listeria monocytogenes infection in mice.
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A Nakane M Asano S Sasaki S Nishikawa T Miura M Kohanawa T Minagawa 《Infection and immunity》1996,64(9):3901-3904
The role of transforming growth factor beta (TGF-beta) in host resistance against Listeria monocytogenes infection was studied with mice. The constitutive expression of TGF-beta 1 mRNA was observed in the spleens and livers of mice before and after infection. Injecting the mice with anti-TGF-beta 1 peptide serum resulted in diminished antilisterial resistance, whereas the administration of human platelet-derived TGF-beta 1 enhanced the resistance. Moreover, mice were protected against lethal infection when treated with TGF-beta 1. These results suggest the TGF-beta 1 might be involved in antilisterial resistance. On the other hand, injecting the mice with TGF-beta 1 resulted in a decrease in the titers of endogenous gamma interferon, tumor necrosis factor alpha, and interleukin-6, which are crucial in antilisterial resistance, in sera and in extracts of spleen and liver. Thus, a complicated mechanism might be involved in the role of TGF-beta 1 in host resistance against L. monocytogenes infection. 相似文献
30.
Lon,a stress-induced ATP-dependent protease,is critically important for systemic Salmonella enterica serovar typhimurium infection of mice
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Takaya A Suzuki M Matsui H Tomoyasu T Sashinami H Nakane A Yamamoto T 《Infection and immunity》2003,71(2):690-696
Studies on the pathogenesis of Salmonella enterica serovar Typhimurium infections in mice have revealed the presence of two prominent virulence characteristics-the invasion of the nonphagocytic cells to penetrate the intestinal epithelium and the proliferation within host phagocytic cells to cause a systemic spread and the colonization of host organs. We have recently demonstrated that the ATP-dependent Lon protease of S. enterica serovar Typhimurium negatively regulates the efficiency of invasion of epithelial cells and the expression of invasion genes (A. Takaya et al., J. Bacteriol. 184:224-232, 2002). This study was performed to reveal the contribution of the Lon protease to the virulence of S. enterica serovar Typhimurium in mice. Determination of 50% lethal doses for the lon disruption mutant and wild-type strain revealed that the mutant was highly attenuated when administered either orally or intraperitoneally to BALB/c mice. The mutant was also found to be able to reach extraintestinal sites but unable to proliferate efficiently within the spleen and cause lethal systemic disease of mice. Macrophage survival assays revealed that the lon disruption mutant could not survive or proliferate within murine macrophages. In addition, the mutant showed extremely increased susceptibility to hydrogen peroxide, which contributes to the bactericidal capacity of phagocytes. The mutant also showed increased sensitivity to acidic conditions. Taken together, the impaired ability of the lon disruption mutant to survive and grow in macrophages could be due to the enhanced susceptibility to the oxygen-dependent killing mechanism associated with respiratory burst and the low phagosomal pH. These results suggest that the Lon protease is essentially involved in the systemic infection of mice with S. enterica serovar Typhimurium, which can be fatal. Of further interest is the finding that the lon disruption mutant persists in the BALB/c mice for long periods without causing an overwhelming systemic infection. 相似文献