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21.
Cytomegalovirus (CMV) infection is a major complication after allogeneic hematopoietic stem cell transplantation (Allo-HSCT); however, we have little information on the clinical features of CMV reactivation after cord blood transplantation using reduced-intensity regimens (RI-CBT) for adults. We reviewed medical records of 140 patients who underwent RI-CBT at Toranomon Hospital between January 2002 and March 2005. All the patients were monitored for CMV-antigenemia weekly, and, if turned positive, received preemptive foscarnet or ganciclovir. Seventy-seven patients developed positive antigenemia at a median onset of day 35 (range, 4-92) after transplant. Median of the maximal number of CMV pp65-positive cells per 50,000 cells was 22 (range, 1-1806). CMV disease developed in 22 patients on a median of day 35 (range, 15-106); 21 had enterocolitis and 1 had adrenalitis. CMV antigenemia had not been detected in 2 patients, when CMV disease was diagnosed. CMV disease was successfully treated using ganciclovir or foscarnet in 14 patients. The other 8 patients died without improvement of CMV disease. In multivariate analysis, grade II-IV acute graft-versus-host disease was a risk factor of CMV disease (relative risk 3.48, 95% confidential interval 1.47-8.23). CMV reactivation and disease develop early after RI-CBT. CMV enterocolitis may be a common complication after RI-CBT.  相似文献   
22.
The electrical and pharmacological properties of the low-threshold Ca2+ current were compared among the newborn, adult and aged rats using the isolated hippocampal CA1 pyramidal neurons. The current-voltage relationship and the time constant of the decay phase of the low-threshold Ca2+ current in adult and aged rats were similar to those in newborn rats. The low-threshold Ca2+ current of adult and aged rats was also sensitive to nicardipine, a dihydropyridine derivative, same as that of newborn rats. We concluded that the nature of low-threshold Ca2+ current in the rat hippocampal CA1 pyramidal neurons is not affected by the aging.  相似文献   
23.
To investigate the relationship between human T-lymphotropic virus (HTLV) types I and II and the pathogenesis of autoimmune thyroid diseases, we examined serum anti-thyroid antibodies in 1019 blood donors with or without serum anti-HTLV-I antibody as well as proviral DNA for HTLV-II in leukocyte DNA by the polymerase chain reaction in 395 blood donors with or without anti-thyroid antibodies. The frequency of donors with anti-HTLV-I antibody who also showed anti-thyroid antibodies (7.9%) tended to be higher than that (6.3%) among donors who did not have the anti-HTLV-I antibody. The frequency of anti-thyroid antibodies in 125 young male donors aged 16–39 years with anti-HTLV-I antibody (4.8%) was significantly higher (P<0.05) than that (0.6%) in 164 control donors without the antibody. In blood donors with anti-thyroid antibody, 25.0% of those with anti-HTLV-I antibody and 14.3% of those without the antibody had HTLV-II proviral DNA. In contrast, in donors without anti-thyroid antibody HTLV-II proviral DNA was detected in 2.3% of those with anti-HTLV-I antibody and in 0.6% of those without the anti body. Thus the detection rates in donors with anti-thyroid antibody were significantly higher (P<0.001) than those in donors without the antibody, regardless of HTLV-I infection. These results suggest that HTLV-I infection and the presence of HTLV-II proviral DNA may be independently related to the pathogenesis of autoimmune thyroid diseases.Abbreviations HTLV Human T-lymphotropic virus - PCR Polymerase chain reaction  相似文献   
24.
Risk factors for distant metastasis were studied in 82 patients with follicular thyroid carcinoma (FTC). Metastases to either the lung or bone existing at the time of presentation were confirmed by I-131 radio-iodine uptake in 10 patients. FTC with an insular component was found in eight patients. Univariate analysis of 14 possible risk factors showed 7 to be statistically significant: insular component, poorly differentiated carcinoma, trabecular component, serum thyroglobulin level before surgery, patient age at the time of presentation, solid component, and vascular invasion (ranked by p values). After further analysis of the interrelation of the factors and of the logistic regression curves, we concluded that presence of an insular component and patient age were the only independent risk factors. Distant metastasis was not detected in any of the 27 patients ≤49 yr old. Among the 55 older patients (≥50 yr old), 5 of the 49 (10%) without an insular component and 5 of the 6 (83%) with an insular component had distant metastasis. The remaining older patient with an insular component but without distant metastasis showed a gradual increase in thyroglobulin levels after total thyroidectomy.  相似文献   
25.
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   
26.
A variety of pathological changes are seen in lymphoproliferative disorders of the lung but the histogenesis of these abnormalities is not yet fully understood. We previously showed that adenovirus vector-mediated transient expression of both the human interleukin-6 (IL-6) and IL-6 receptor (IL-6R) genes, but not the IL-6 gene alone, in the rat lung induced lymphocytic alveolitis. In the present study, we explored the lung pathology of human IL-6 and IL-6R double transgenic mice to elucidate the effects of prolonged IL-6 signalling on the lung. The transgenic animals developed mononuclear cell accumulation in peribronchovascular regions, but little infiltration into alveolar spaces. Immunohistochemical analysis revealed that the cellular accumulations contained not only mixtures of inflammatory cells but also lymphoid tissue-like structures. As the expression of CXCL13/BLC, the indispensable chemokine for lymphoid organogenesis, was recognized in the B cell follicles of the pulmonary lesions, we speculate that this chemokine plays an inductive role in the development of the lymphoid tissue-like structures. These structures were distinguished from bronchus-associated lymphoid tissues (BALTs) by their location and by the lack of lymphoepithelium, which is a characteristic of BALT. These findings imply that IL-6 signalling may play a role in the pathogenesis of lymphoproliferative disorders of the lung.  相似文献   
27.
The post-traumatic change of the voltage-dependent Mg(2+) block of N-methyl-D-aspartate response was investigated using nystatin perforated patch recording mode under the voltage-clamp condition. Motor neurons of the dorsal motor nucleus of vagus nerve were freshly dissociated from rat brain at 2h to 10 days after receiving axonal crush injuries in vivo at the neck. The reduction of voltage-dependent Mg(2+) block of N-methyl-D-aspartate response became evident at more than 12h after the injury, sustained for at least five days and recovered within 10 days. Other characteristics examined such as reversal potentials, the Hill coefficient and EC(50) of N-methyl-D-aspartate-induced current were not affected by axonal injury. The Mg(2+) block of N-methyl-D-aspartate response was not affected at all by local application of colchicine onto the vagal axon in in vivo condition, suggesting that axonal injury, but not the blockade of the axonal flow, is responsible for the change of the sensitivity of N-methyl-D-aspartate response to extracellular Mg(2+). In addition, the reduction of Mg(2+) block by the nerve injury persisted regardless of the presence of protein kinase C modulators, such as 10(-6)M chelerythrine and 10(-7)M calphostin C. Therefore alteration of protein kinase C activity after axonal injury is not responsible for the maintenance of the reduced Mg(2+) block.These findings suggest that injured neurons acquire immature characteristics of plasticity with respect to the sensitivity of N-methyl-D-aspartate receptors to extracellular Mg(2+) or a long-term increase in the susceptibility to Ca(2+) excitotoxicity.  相似文献   
28.
29.
1. The pharmacologic properties of gamma-aminobutyric acid (GABA)-induced Cl- current (ICl) were studied in the paratracheal ganglion cells freshly dissociated from 7- to 10-day-old rat trachea in a whole-cell recording mode by the use of a conventional patch-clamp technique. 2. GABA- and muscimol-induced currents increased sigmoidally in a concentration-dependent manner, and both currents reversed at approximately -3 mV, which was close to the Cl- equilibrium potential (ECl). 3. Strychnine (STR) at low concentration and bicuculline (BIC) inhibited GABA response competitively, whereas STR at the higher concentrations, benzylpenicillin (PCG), or picrotoxin (PTX) inhibited noncompetitively. Inhibition of GABA response by PCG but not other antagonists was voltage dependent, indicating that PCG acts as a Cl- channel blocker. 4. The concentration-response curve of pentobarbital sodium (PB)-induced ICl was bell shaped. At concentrations higher than 10(-3) M, both the peak and plateau currents decreased, and a transient "hump" current appeared immediately after washing out PB. In the presence of PB, the concentration-response curve of GABA shifted toward left without changing the maximum response. 5. Although diazepam (DZP) at concentration used did not induce a response, it potentiated the GABA response in a concentration-dependent manner between 10(-8) and 10(-6) M. DZP also caused a parallel shift toward left in the concentration-response curve of GABA. 6. PB or DZP further enhanced the GABA response in the presence of the other agent. 7. It is concluded that the properties of GABAA receptors in the paratracheal ganglion cells are essentially similar to those reported in other preparations.  相似文献   
30.
An electron microscopic immunohistochemical localization of thyroglobulin (TG) using PAP methods has been made in 15 cases of cold follicular adenoma. All cases of follicular adenoma showed organ specific functions such as synthesis, storage, reabsorption, and hydrolysis of thyroglobulin except for an area composed of follicular cells with trabecular arrangement. Immuno-reaction product for TG was precisely demonstrated in follicular lumina, subapical vesicles and reabsorbed colloid droplets. The reaction product observed in the follicular lumen was clearly demarcated from the cytoplasm of the follicular cells by the apical plasma membrane. The subapical vesicles ranging approximately from 50 mμ to 300 mμ in diameter were rarely observed in follicular adenoma and some of them fused with the reabsorbed colloid droplets. The reabsorbed colloid droplets usually had the intense reaction product and hydrolyzed colloid droplets had a vacuole containing floccular low electron dense materials. There is no reaction product in rough endoplasmic reticulum and Golgi complexes.  相似文献   
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