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61.
Heated extracts prepared from the mantle muscles (for decapods) or leg muscles (for octapods) of nine species of cephalopods were shown to be all reactive with serum IgE in crustacean-allergic patients. No marked difference in the reactivity with IgE was recognized among the cephalopods, suggesting that they are almost equally allergenic. Immunoblotting and inhibition immunoblotting data revealed that the major allergen is tropomyosin in common with the nine species of cephalopods and that the cephalopod tropomyosins are cross-reactive with one another and also with crustacean tropomyosins. Molecular cloning experiments first elucidated the primary structures of tropomyosins from five species of cephalopods. The cephalopod tropomyosins show high sequence identity (more than 92% identity) with one another, being the molecular basis for their cross-reactivity. Although the sequence identity between cephalopod and crustacean topomyosins is only about 63–64%, some of the IgE-binding epitopes proposed for brown shrimp Penaeus aztecus tropomyosin (Pen a 1) are well conserved in the cephalopod tropomyosins, supporting the cross-reactivity between cephalopod and crustacean tropomyosins.  相似文献   
62.
We identified two novel missense mutations in exon 1 of adrenoleukodystrophy (ALD) gene in two unrelated Japanese families. The first, G(874)C transition results in Arg(163)Pro substitution in the cytoplasmic domain of the ALD protein in adrenomyeloneuropathy family. The second, C(679)G results in Ser(98)Trp substitution in the first transmembrane loop in childhood onset cerebral ALD family. Both mutations cause the substitution of polar amino acid (arginine and serine) with non-polar amino acid (proline and tryptophan). Bone marrow transplantation (BMT) from his non-affected his younger sister was performed on a boy with childhood onset cerebral ALD who showed neurological deficit and brain MRI abnormalities. We evaluated the effect of BMT over a 6-year period in terms of neurological deficit, the level of very-long-chain fatty acids (VLCFA) in plasma and fibroblasts, and brain MRI. After BMT, patient's peripheral white blood cells were replaced by donor's XX ones carrying a normal ALD gene confirmed by in situ hybridization using satellite DNA of the centromere of X and Y chromosomes as probes and the level of VLCFA in lymphocytes was within normal limit. However, his neurological state progressively deteriorated. BMT was not beneficial to him.  相似文献   
63.
Octanoate is taken up by the brain and converted in astrocytes to glutamine through the TCA cycle after beta-oxidation. Consequently, [1-11C]octanoate might serve as a useful positron emission tomography (PET) probe for studying cerebral oxidative metabolism and/or astroglial functions. The present study attempted to evaluate the utility of using [1-11C]octanoate as a PET tracer for imaging and evaluating the pathophysiology of ischemic stroke. We used a canine model of thromboembolic stroke. Five male beagle dogs were implanted with an indwelling catheter in the left internal carotid artery. A single autologous blood clot was injected into the left internal carotid artery through the catheter. The brain distribution of [1-11C]octanoate and cerebral blood flow (CBF) were determined 24 h after insult using a high resolution PET scanner. Post mortem brain regions unstained with 2,3,5-triphenyltetrazolium chloride (TTC) were defined as infarcts. In the region of an infarct, accumulation of [1-11C]octanoate decreased concurrently with CBF reduction. In contrast, normal accumulation of [1-11C]octanoate was observed in ischemic but vital regions, suggesting that an increased accumulation of [1-11C]octanoate relative to CBF takes place in these regions. In conclusion, [1-11C]octanoate accumulated in ischemic but vital regions, indicating that [1-11C]octanoate is a potentially useful PET tracer for imaging and evaluating the pathophysiology of ischemic stroke.  相似文献   
64.
The supernatants from cultures of alveolar macrophages from 12 patients with sarcoidosis and 7 control subjects were assayed for interleukin-6 (IL-6) using an ELISA system. IL-6 was detectable without a stimulant in supernatants from all subjects with sarcoidosis and controls. However, the supernatants from 4 of 12 untreated patients with sarcoidosis contained significantly greater amounts of IL-6. When macrophages were stimulated by Propionibacterium acnes (P. acnes), the mean level of IL-6 in the supernatant of patients with sarcoidosis was 5.18 +/- 1.46 ng/ml, which was significantly higher than in controls (3.34 +/- 0.39) (p less than 0.05). Furthermore, in patients with sarcoidosis, the mean level of IL-6 in the supernatant was significantly correlated with the percentage of lymphocytes in bronchoalveolar lavage fluid (p less than 0.05), the level of interleukin-1 released by alveolar macrophages stimulated by P. acnes (p less than 0.05), and the phagocytic index of alveolar macrophages (p less than 0.05). The large amount of IL-6 in the supernatant after stimulation by LPS was measured in patients with sarcoidosis (24.49 +/- 13.36) and in controls (12.4 +/- 8.53), and there was no significant difference between patients with sarcoidosis and controls. Small amounts of IL-6 were detectable in bronchoalveolar fluid from only 2 of 26 patients with sarcoidosis; however, it was detected in none of 15 controls. It is suggested that the enhancement of IL-6 release by alveolar macrophages has a role in the activation of immune effector cells at sites of sarcoidosis.  相似文献   
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Real-time magnetic resonance (MR) imaging enables the application of percutaneous microwave coagulation for high-risk patients with metastatic liver tumours. The tumours, local vessels and bile ducts can be observed clearly in three-dimensional sections and a sufficient surgical margin can be confirmed on the MR image even during the coagulation procedure. MR-guided percutaneous microwave coagulation therapy is effective for treatment of not only primary liver tumours but also metastatic breast cancers in the liver, which are not diffuse but discrete, and difficult to treat with only chemo-and endocrine therapy. We report a 44-year-old Japanese woman who underwent modified radical mastectomy for right breast cancer (T1c N0 M0 Stage I). Three years after the operation, she developed two metastatic liver tumours and was treated by MR-guided percutaneous microwave coagulation, achieving a complete response (CR) without any recurrence for 15 months as of the present. The most beneficial aspect of MR-guided percutaneous microwave coagulation is its safety. It is only minimally invasive and can be repeated. This therapy, therefore promises to prolong the disease free period. Additional clinical trials will be valuable to delineate the effectiveness and safety of MR-guided percutaneous microwave coagulation therapy for controlling the liver metastases of breast cancer.  相似文献   
68.
BACKGROUND: Liver metastases from breast cancer are associated with a poor prognosis, however, local control with microwave thermocoagulation therapy has been used in certain subgroups of these patients in the past decade. In this study, open-configuration magnetic resonance (MR) -guided microwave thermocoagulation therapy was used for metastatic liver tumors from breast cancer, and the efficacy of this treatment was assessed. METHODS: Between June 2000 and April 2004, we used MR-guided microwave thermocoagulation therapy on 11 nodules in 8 patients with metastatic liver tumors from breast cancer. The procedure was carried out under general anesthesia. A 0.5 T open-configuration MR system and a microwave coagulator were used. Near-real-time MR images and real-time temperature images were collected and displayed on the monitor. The MR-compatible thoracoscope was used and combined with MR imaging guidance. Navigation software, a 3D Slicer, was installed and customized. RESULTS: The customized navigation software displayed near-real-time MR images. The percutaneous puncture into the tumors was successful in all cases. No mortality or major complications occurred as a result of the procedures. Five of the 8 patients are alive with new metastatic foci with a mean observation period of 25.9 months. CONCLUSIONS: We developed several devices to allow safe, easy, and accurate MR-guided microwave thermocoagulation therapy of liver tumors. Open-configuration MR-guided microwave thermocoagulation therapy appears to be a feasible method for tumor ablation of metastatic liver tumors from breast cancer.  相似文献   
69.
Recent studies have demonstrated that intermittent administration of parathyroid hormone (PTH) enhances osteogenesis (hard callus formation) and increases mechanical strength in experimental fracture healing. Thus far, however, effects of PTH on chondrogenesis (soft callus formation) during fracture healing have not been fully elucidated. In the present study, we analyzed the underlying molecular mechanism by which exogenous PTH would affect chondrogenesis in a model of experimental fracture healing. Unilateral femoral fractures were produced in 2-month-old Sprague-Dawley rats. Daily subcutaneous injections of 10 microg/kg of recombinant human PTH(1-34) [rhPTH(1-34)] were administered over a 28-day period of fracture healing. Control animals were injected with vehicle solution (normal saline) alone. The results showed that, on day 14 after fracture, cartilage area in the PTH-treated group was significantly increased (1.4-fold) compared with the controls, but this increase was not observed at days 21 and 28. In the early stage of chondrogenesis (days 4-7), cell proliferation, expressed as the rate of proliferating cell nuclear antigen-positive cells, was increased in mesenchymal (chondroprogenitor) cells but not chondrocytes in the PTH-treated group compared with controls. In addition, gene expression of SOX-9 was up-regulated in the PTH-treated group on day 4 (1.4-fold), and this was accompanied by enhanced expression of pro-alpha1 (II) collagen (1.8-fold). After 14 days, there were no significant differences between groups in either cell proliferation or the expression levels of cartilage differentiation-related genes (SOX-9, pro-alpha1 (II) collagen, pro-alpha1 (X) collagen and osteopontin). These results suggest that intermittent treatment with low-dose rhPTH(1-34) induces a larger cartilaginous callus but does not delay chondrocyte differentiation during fracture healing.  相似文献   
70.
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