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21.
Previously we reported disease-specific interaction between interferon- (IFN-) and interleukin-4 (IL-4) in patients with IgA nephropathy (IgAN), suggesting the existence of unusual T cell behavior in this disease. In the present study, we investigated characteristic synthesis of interferon- (IFN-) and expression of IFN- receptor (IFN-R) in the peripheral blood mononuclear cells (PBMC) from patients with IgAN and other chronic proliferative glomerulonephritis (PGN). Heparinized peripheral blood samples were obtained from 38 patients with chronic mesangial proliferative glomerulonephritis (CGN; including 24 with IgA nephropathy) and 20 healthy controls. PBMC were isolated by gradient centrifugation and fragments were cultured in Iscove's modified Dulbecco's medium (IMDM) supplemented with 10% fetal calf serum (FCS) for 72 hr. IFN- concentrations in supernatants were evaluated by the enzyme-linked immunosorbent assay (ELISA). Other parts of PBMC pellets were reacted with anti-human IFN-R monoclonal antibody and FITC-labeled anti-mouse second antibody for analysis of IFN-R expression on these cells by FACScan. The remaining PBMC were fractionated into CD4+ T cells, CD8+ T cells, B cells, NK, cells and macrophages using the MACS cell sorting system. The isolated cells were evaluated for IFN- or IFN-R mRNA expression by the semiquantitative RT-PCR method.In vitro IFN- synthesis was enhanced in patients with CGN, and NK cells were revealed to be responsible for such enhancement. On the other hand, the expression of IFN-R on macrophages was suppressed in CGN patients. These results suggest that impairment of regulation of the IFN- system might be involved in the development of CGN.  相似文献   
22.
The present study investigated the development of plasma cells in the early rat yolk sac (days 10-16 of gestation) by light microscopy, transmission electron microscopy, immunoelectron microscopy, and indirect immunofluoresce techniques. Cells delineating the morphology of plasma cells in the yolk sac were observed as early as 12 days of embryonic life. As for positive immune staining for the intra-cytoplasmic immunoglobulin (Ig) production (IgA, IgM and IgG), the intensity of the immune staining was very weak on days 10 and 11 of gestation, while it turned very dense on day 12 of gestation. At 14 days of gestation, the number of positive cells was markedly reduced. Immunoelectron microscopy visualized products of the immune reaction in cisterns of the rough endoplasmic reticulum. Conventional electron microscopic examination of 12, 13, and 16-day yolk sacs confirmed the development and differentiation of plasma cells with their well-known ultrastructural features, making this the first study to demonstrate these in the early rat yolk sac. The development of plasma cells in the early yolk sac implies the ability of the yolk sac to effect a humoral immune response at this stage of fetal life. The probable role of plasma cells in the yolk sac is also discussed.  相似文献   
23.
When a saccade occurs to an interesting object, visual fixation holds its image on the fovea and suppresses saccades to other objects. Electrical stimulation of the frontal eye field (FEF) has been reported to elicit saccades, and recently also to suppress saccades. This study was performed to characterize properties of the suppression of visually guided (Vsacs) and memory-guided saccades (Msacs) induced by electrical stimulation of the FEF in trained monkeys. For any given stimulation site, we determined the threshold for electrically evoked saccades (Esacs) at < or =50 microA and then examined suppressive effects of stimulation at the same site on Vsacs and Msacs. FEF stimulation suppressed the initiation of both Vsacs and Msacs during and about 50 ms after stimulation at stimulus intensities lower than those for eliciting Esacs, but did not affect the vector of these saccades. Suppression occurred for ipsiversive but not contraversive saccades, and more strongly for saccades with larger amplitudes and those with initial eye positions shifted more in the saccadic direction. The most effective stimulation timing for suppression was about 50 ms before saccade onset, which suggests that suppression occurred in the efferent pathway for generating Vsacs at the premotor rather than the motoneuronal level, most probably in the superior colliculus and/or the paramedian pontine reticular formation. Suppression sites of ipsilateral saccades were distributed over the classical FEF where saccade-related movement neurons were observed. The results suggest that the FEF may play roles in not only generating contraversive saccades but also maintaining visual fixation by suppressing ipsiversive saccades.  相似文献   
24.
BackgroundMyotubular myopathy is a rare disease sometimes accompanied by peliosis hepatis, a leading cause of fatal liver hemorrhage.Case ReportWe present a case of a 2-year-old boy with myotubular myopathy who developed liver hemorrhage because of peliosis hepatis and was successfully treated with living-donor liver transplant. The patient initially presented with fever, anemia, and liver dysfunction. A computed tomographic scan revealed hemorrhages in the liver, and the patient underwent hepatic artery embolization twice. After the second embolization, multiple peliosis hepatis cavities appeared in the left lobe of the liver that had increased in size. Therefore, the patient underwent ABO-incompatible living-donor liver transplant using a lateral segment graft from his father. The patient developed severe septic shock with an unknown focus on postoperative day 18, which resolved with antibiotic therapy. On postoperative day 62, he was discharged. Fourteen months after undergoing living-donor liver transplant, the patient showed no recurrence of peliosis hepatis.ConclusionsAlthough the long-term prognosis of peliosis hepatis due to myotubular myopathy after living-donor liver transplant remains unclear, liver transplant may be a curative treatment for patients with myotubular myopathy who have uncontrollable peliosis hepatis.  相似文献   
25.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
26.
The antihypertensive action of KRN4884 (5-amino-N-[2-(2-chlorophenyl)ethyl]-N'-cyano-3-pyridinecarboxamidine ), a newly synthesized 3-pyridine derivative was examined in conscious spontaneously hypertensive rats (SHRs). A single administration of KRN4884 (0.5, 1.5 mg/kg, p.o.) produced a dose-dependent and long-lasting antihypertensive effect. The 7-day repeated administration of KRN4884 (0.5, 1.5 mg/kg, p.o.) did not diminish antihypertensive activity during the treatment period or induce rebound hypertension after the discontinuation of treatment. To examine the mechanism of the antihypertensive effect of KRN4884, we studied its vasorelaxing effects in rat isolated aortae precontracted with 25 mM KCl. Single application of KRN4884 showed a slower onset of inhibitory action than that of levcromakalim. KRN4884 was approximately 26-fold more potent than levcromakalim and 10-fold less potent than nilvadipine. KRN4884- and levcromakalim-induced vasorelaxation were antagonized by glibenclamide. Furthermore, we observed the recovery of the contraction inhibited by these drugs after repeated washing. The inhibitory effect of KRN4884 was restored only after four washes, whereas that of levcromakalim was completely restored after one wash. The nilvadipine-induced inhibitory effect was the most resistant to washing among these drugs. These results suggest that KRN4884 shows a long-lasting antihypertensive effect based on its potent potassium channel-opening action. The long-lasting action may be due to a slow association/dissociation with/from the binding sites on vascular smooth muscle.  相似文献   
27.
We examined the efficacy of two new preservation solutions containing trehalose-an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution — in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n=5 for each solution) after pretreatment with PGE1 (20 g/kg) and were stored for 20 h at 4°C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.  相似文献   
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