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81.
The copper and Iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than In LEA rats (P<0.05). But for the free iron level there was no signiflcant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher In LEC rats than In LEA rats (P<0.01). The 4–hydroxy-2–nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect In the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneo-plastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important translation metals In the body, may participate In the Induction of DNA damage and oncogenesls  相似文献   
82.
83.
Inhaled beta(2)-agonists (long-acting as well as short acting) are used world-wide for the relief of asthma symptoms. However, there are few reports which have evaluated the additive effect of short-acting beta(2)-agonists to long-acting beta(2)-agonists on airway resistance measured by a plethysmography. This study was designed to evaluate the additive effect of inhaled short-acting beta(2)-agonists (protecarol) to long-acting beta(2)-agonists (salmeterol) on airway resistance in normal healthy volunteers (S+P group). In addition, to compare the effects of beta(2)-agonists which have different types of intrinsic activities, acute effect of inhaled procaterol adding to procaterol was also evaluated (P+P group). Seven healthy volunteers (all male and all non-smokers) were entered in this study. Pulmonary function was measured by a body plethysmography. Forced expiratory volume per 1 second (FEV1), the maximum flow rate at 25% (V(.) 25), the maximum flow rate at 50% of forced vital capacity (V(.) 50), and airway resistance were measured before and after inhalation of salmeterol (1 dry powder, 50 microg) or procaterol (2 puffs, 20 microg). Sixty minutes after inhalation of salmeterol, or 15 minutes after inhalation of procaterol, inhalation of procaterol (2 puffs, 20 microg) was added, and then pulmonary function was monitored. FEV1, V(.) 25, and V(.) 50 were significantly increased after inhalation of salmeterol as well as procaterol. In addition, airway resistance decreased significantly after inhalation of salmeterol as well as procaterol. In the S+P group, additional decrease of airway resistance after inhalation of procaterol was relatively small compared with the P+P group. In conclusion, although additional bronchodilatoric effects were observed in the S+P and P+P group, the effects seemed to be different based on the intrinsic activity of each beta(2)-agonist.  相似文献   
84.
Summary Unit activites of secondary vestibular neurons that selectively responded to stimulation of the anterior semicircular canal nerve (ACN) were recorded extracellularly in the anesthetized cat. Axonal pathways and projections in the spinal cord of the ACN-activated neurons were examined by recording their antidromic responses to stimulation of the lateral and medial vestibulospinal tracts (LVST and MVST), and the bilateral neck extensor motoneuron pools in the C1segment (C1dorsal rami [DR] motoneuron pools). In order to determine whether the neurons had ascending axon collaterals to the extraocular motoneurons, the contralateral (c-) inferior oblique (IO) motoneuron pool was also stimulated. Twenty-seven neurons sent their axons to the ipsilateral (i-) C1DR motoneuron pool via the LVST without any projection to the extraocular motoneuron pool. All the cells except one were located in the ventral part of the lateral vestibular nucleus. This pathway produced monosynaptic EPSPs with short time-to-peak and short half-width in C1DR motoneurons (16/16 motoneurons). Eight neurons sent axons to the i-C1DR motoneuron pool via the MVST without any to the extraocular motoneuron pool. Cell somata were located in the descending nucleus or in the ventral part of the lateral nucleus. These neurons did not produce postsynaptic potentials (PSPs) in any C1DR motoneurons. All thirty-five neurons sending axons to the c-C1DR motoneuron pool have ascending axon collaterals to the c-IO motoneuron pool.  相似文献   
85.
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis.  相似文献   
86.
87.
The CX3C chemokine fractalkine (CX3CL1) exists as both a membrane-bound form promoting firm cell-cell adhesion and a soluble form chemoattracting leukocytes expressing its receptor CX3CR1. When adenoviral vector expressing mouse fractalkine (AdFKN) was transduced to the tumor cells, fractalkine was expressed as both membrane-bound form on the tumor cells and soluble form in the supernatant in vitro. Intratumoral injection of AdFKN (1 x 10(9)PFU/tumor) into C26 and B16F10 tumors resulted in marked reduction of tumor growth compared to control (C26: 86.5%, p<0.001; B16F10: 85.5%, p<0.001). Histological examination of tumor tissues revealed abundant infiltration of NK cells, dendritic cells, and CD8(+) T lymphocytes 3 and/or 6 days after treatment with AdFKN. Splenocytes from mice treated by AdFKN developed tumor-specific cytotoxic T cells, and thereby protected from rechallenging with parental tumor cells. Antitumor effects by AdFKN were completely abrogated in both NK cell-depleted mice and CD8(-/-) mice, and partially blocked in CD4(-/-) mice. These data indicated that fractalkine mediates antitumor effects by both NK cell-dependent and T cell-dependent mechanisms. This study suggests that fractalkine can be a suitable candidate for immunogene therapy of cancer because fractalkine induces both innate and adaptive immunity.  相似文献   
88.
The aim of this study was to search for diagnostic markers that could correctly identify thyroid nodular lesions requiring urgent surgical treatment. We investigated whether galectin-3 and dipeptidyl peptidase IV (CD26/DPPIV) could be potential markers for improving the diagnostic accuracy of conventional cytology. Seventy-nine patients with histologically proven thyroid diseases were analyzed. The immunocytochemical staining results showed galectin-3 expression in neoplastic cells of all 37 papillary carcinomas, five of six follicular carcinomas, all three anaplastic carcinomas, one of three medullary carcinomas, and two of 14 follicular adenomas. All 16 adenomatous goiters were negative for galectin-3 immunostaining. On the other hand, all 37 papillary carcinomas, all six follicular carcinomas, and one of three anaplastic carcinomas revealed CD26/DPPIV expression, whereas all three medullary carcinomas were negative. Among benign thyroid lesions, four of 14 follicular adenomas and two of 16 adenomatous goiters exhibited varying degrees of immunoreactivity for CD26/DPPIV. RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma. In conclusion, we demonstrate that galectin-3 and CD26/DPPIV were consistently coexpressed at protein and mRNA levels in differentiated thyroid carcinomas. We propose that combined immunostaining for galectin-3 and CD26/DPPIV in the preoperative evaluation of thyroid nodules may play a role in accurate cytodiagnosis.  相似文献   
89.
Cloned TS4.44 cells, which were hybridized HAT-sensitive 3T3-4E cells with B cells stimulated by immune complexes produce a lymphokine, biochemical and biological characteristics of which are identical with those of conventional suppressive B cell factor (SBF) synthesized by Fc receptor bearing B cells stimulated with immune complexes. This factor is known to suppress B cell responses to antigen/mitogen. The present studies were carried out by using this hybridoma-derived SBF to characterize the large proportion of B cells sensitive to SBF and the small proportion of B cells resistant to it in terms of affinities of antibodies which these cells are able to produce. The treatment of normal spleen cells with SBF resulted in a 50-70% decrease in anti-dinitrophenyl (DNP) antibody production when the cells were transferred into X-ray-irradiated mice along with alum-precipitated dinitrophenyl-conjugated keyhole limpet hemocyanin (DNP-KLH). The affinity of anti-DNP antibody molecules produced in these mice was significantly lower than that of the controls, even if immunization was repeated. The target cells for SBF were B, and not helper T cells which might be involved in the process of affinity maturation. A single treatment of spleen cells in vitro with SBF was sufficient to abrogate the precursors committed to mediate high-affinity anti-DNP antibody responses, since the retreatment with SBF in vitro and transfer into the second irradiated recipients along with antigens of spleen cells of mice to which SBF-treated spleen cells were transferred 3 weeks before resulted in almost the same level of plaque-forming-cell-responses as in mice which received medium-treated.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
90.
Purpose

Intravesical bacillus Calmette–Guérin (BCG) is the standard of care for bladder carcinoma in situ (CIS). The response to BCG therapy against CIS is generally assessed by random bladder biopsy (RBB). In this study, we examined the necessity of routine RBB after BCG therapy.

Methods

We retrospectively identified 102 patients who were initially diagnosed with CIS with or without papillary tumor and received subsequent 6–8-week BCG therapy. Thereafter, all patients underwent voiding cytology analysis, cystoscopy, and RBB to evaluate the effects of BCG therapy. We evaluated the association between clinical parameters (voiding cytology and cystoscopy findings) and the final pathological results by RBB specimens.

Results

According to the pathological results of RBB, 30 (29%) patients had BCG-unresponsive disease (remaining urothelial carcinoma was confirmed pathologically) and 20 were diagnosed with CIS. Positive/suspicious voiding cytology and positive cystoscopy findings were well observed in patients who had BCG-unresponsive disease compared with their counterparts (p?=?0.116, and p?<?0.001, respectively). The sensitivity (Sen.), specificity (Spe.), positive predictive value (PPV), and negative predictive value (NPV) of voiding cytology were 50%, 68%, 39%, and 77%, respectively. The values for cystoscopy findings were as follows: Sen.: 87%, Spe.: 57%, PPV: 46%, and NPV: 91%. The values for their combination (having either of them) were as follows: Sen.: 100%, Spe.: 44%, PPV: 43%, and NPV: 100%.

Conclusion

RBB after BCG therapy for patients with negative voiding cytology and negative cystoscopy may be omitted because their risk of BCG-unresponsive disease is significantly low (NPV: 100%).

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