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There are regional variations of sex chromosome morphologies in the Japanese wrinkled frog, Rana rugosa (2n = 26): heterogametic ZZ/ZW-type and XX/XY-type sex chromosomes, and two different types of homomorphic sex chromosomes. To search for homology between the ZW and XY sex chromosomes and the chromosome rearrangements that have occurred during sex chromosomal differentiation in R. rugosa, we performed chromosome mapping of sexual differentiation genes for R. rugosa by FISH. Three genes, AR, SF-1/Ad4BP and Sox3, were localized to both the ZW and XY chromosomes, and their locations were all different between the Z and W and between the X and Y. AR and SF-1/Ad4BP were located on the short arms of the W and X and the long arms of Z and Y, and Sox3 was mapped to the different locations on the long arms between the Z and W and between the X and Y, probably as a result of multiple rearrangements that occurred during the process of sex chromosome differentiation. However, the chromosomal locations of three genes were almost consistent between the Z and Y and between the W and X, indicating that the Z and Y chromosomes and the W and X chromosomes were respectively derived from the same origins. Dmrt1, which is located on avian sex chromosomes, was localized to autosomes in R. rugosa with both the ZW and XY sex chromosomes, suggesting that Dmrt1 might not be related to sex determination in this species.  相似文献   
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BACKGROUND: The exact mechanism of aspirin-induced asthma is not clear. It has been postulated that precipitation of asthma attacks by aspirin is linked to inhibition of COX activity and massive release of cysteinyl leukotriene into the airway. Tacrolimus, a macrolide-derived immunosuppressant, is used for immunosuppression in organ transplantation and also for allergic diseases such as atopic dermatitis. OBJECTIVE: We evaluated the effects of tacrolimus in aspirin-induced asthma by using a double-blind, crossover study design. METHODS: Twelve patients with aspirin-induced asthma (male:female, 3:9; mean age +/- SD, 36.7 +/- 7.2 years) received either tacrolimus (0.1 mg/kg) or placebo 2 hours before the threshold dose of oral aspirin. RESULTS: In the placebo arm, oral aspirin significantly decreased FEV 1 concomitant with significant increases in sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. Tacrolimus significantly inhibited bronchoconstriction and abrogated aspirin-induced increase in both sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. CONCLUSION: The current study suggested that tacrolimus inhibited bronchoconstriction to a threshold dose of aspirin by inhibition of cysteinyl leukotriene excretion.  相似文献   
34.
The catalyzed signal amplification (CSA) technique, based on the peroxidase-mediated deposition of haptenized tyramide and also known as tyramide signal amplification and catalyzed reportor deposition systems, is widely accepted as a signal amplification method for immunohistochemistry and in situ hybridization. In this study, we examined the applicability of a new simplified CSA system employing fluorescyl-tyramide (FT) to pathologic testing and research with formalin-fixed, paraffin-embedded tissues. By using the FT, instead of biotinyl-tyramide (BT) that is commonly employed in the CSA system with chromogen, nonspecific staining caused by endogenous biotin was completely avoided. The FT-CSA system loaded on the automated immunostaining equipment also allowed for more reproducible detection in short times. When applied to cyclin D1 immunostaining that is important in differentiation among small B-cell lymphomas, the system was useful in demonstrating its protein expression in mantle cell lymphomas considered negative or equivocally positive for cyclin D1 in a conventional immunodetection. In immunohistochemistry for phosphorylated proteins and murine hematologic markers that often require higher sensitivity than conventional methods, the FT-CSA system provided desirable staining results with intense signal amplification. Our results indicate that the simplified CSA system employing the FT can be useful in enlarging the target range for routine immunohistochemistry due to its high applicability.  相似文献   
35.
We reported a 4-month-old girl with biotin deficiency caused by amino acid formula. Two weeks after birth, she was diagnosed as having a milk protein allergy. After switching to amino acid formula from usual formula, her symptoms and laboratory findings became normal. About three weeks after the beginning of amino acid formula, she developed intractable skin erosions around the eyes, mouth, neck, and anogenital area. By measuring concentrations of some trace elements, she was diagnosed as having a biotin deficit, because of the organic aciduria and undetectable serum biotin concentration. Her serum biotinidase level was normal. Upon administration of oral biotin supplementation, all her symptoms and laboratory findings were dramatically improved. Since amino acid formula contains very few biotin, we should pay attention to biotin deficiency when infants receiving amino acid formula.  相似文献   
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PROBLEM: Human GRO-alpha (GRO-α) is a new member of the chemokine family that is supposed to play an important role in inflammatory and immune reactions. We established a sandwich enzyme-linked immunoassay (ELISA) system with polyclonal antibodies against human GRO-α and investigated the serum level of healthy donors to establish normal ranges for this chemokine in adults. METHODS: GRO-α concentrations were measured cross-sectionally in the sera of 240 healthy adults. The variability of serum GRO-α levels was also measured in normal volunteers, samples from whom were obtained by sequential venipunctures or by a small plastic cannula with a heparin-saline lock, to determine short-term variability. RESULTS: Whereas there was no difference between the concentration of human GRO-α from men (logarithmic mean, 77.6 pg/ml, n = 120) and that from women with normal menstrual cycles (log mean, 71.6 pg/ml, n = 73), the concentration from postmenopausal women (log mean 45.0 pg/ml, n = 31) was lower than that from women with normal menstrual cycles (log mean 71.6 pg/ml, n = 73). However, we could not detect any significant difference between healthy donors' serum levels and those of donors with acute inflammation. Fewer variations were recognized in the case of the sequential venipunctures method than in that of the heparin-saline lock method. CONCLUSION: We found that the GRO-α concentration of postmenopausal women was significantly lower than that of women with normal menstrual cycles. These results suggest the GRO-α serum levels of normal healthy women may have some correlation with sex hormones.  相似文献   
38.
A simple and rapid method for the determination of macrophage activating factor is described. A new type of apparatus suitable for the measurement of macrophage chemiluminescence was devised, and the effect of lymphokines on macrophage activities was studied by measuring phorbol myristate acetate-induced luminol-dependent chemiluminescence. An outstanding feature of the new apparatus is that the plastic dish used for the cell culture can be used as the vessel for the chemiluminescence reaction. When thioglycollate-elicited ICR mouse peritoneal macrophages were incubated with lymphokines, their ability to generate chemiluminescence increased rapidly, reaching a maximal level at about 4 h, and then it progressively decreased to the control level at 8 h. Although this increasing effect of lymphokines on macrophage chemiluminescence was short-lived, it could be seen at a relatively low concentration, at which lymphokine-mediated cytotoxic activity of macrophages was not observed.  相似文献   
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A new type of chemiluminescence (CL) was observed in thioglycolate-elicited ICR mouse peritoneal macrophages which had been incubated for 24 h in medium containing lymphokines (LK) and lipopolysaccharides (LPS), and then exposed to a CL reagent solution containing luminol and phorbol myristate acetate (PMA). The new CL, which was clearly distinguishable from PMA-induced CL, appeared immediately after the addition of the CL reagent solution, reaching a maximal level at about 30 s, and disappeared rapidly. We have called the new CL 'spontaneous CL', since it appeared spontaneously without PMA triggering. When the macrophages were incubated with LK in the presence of 10 ng/ml of LPS, the spontaneous CL began to appear after about 4 h incubation, the maximal level being reached at about 12 h, after which it decreased gradually on further incubation. After 48 h, it could not be observed at all. The spontaneous CL could be observed only in macrophages simultaneously treated with LK and LPS, as in the case of cytotoxicity. The correlation between spontaneous CL and cytotoxicity was suggested by the following; they showed a similar dose dependency to LK, and neither of them could be induced in aged macrophages which had been incubated in vitro for 1 day before exposure to LK and LPS. These results suggest that spontaneous CL measurement could possibly replace the cytotoxicity test as a simple method for the determination of macrophage activating factor.  相似文献   
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