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101.
A 22-year-old female with ulcerative colitis that was successfully treated with infliximab (IFX), and remained stable following tapered discontinuation of prednisolone, developed anterior neck pain and elevation of C-reactive protein following her fourth administration of IFX. She was diagnosed with Takayasu arteritis (TA) based on neck ultrasound and computed tomography angiography. This is the first report describing the development of TA during treatment of UC with IFX.  相似文献   
102.
We report on a pair of male monozygotic twins, one unaffected and the other affected with gonadotropin-releasing hormone (GnRH)-dependent precocious puberty, and discuss the role of treatment with a GnRH analog in the attainment of full height potential in GnRH-dependent precocious puberty. At 1.6 years of age, the affected twin was studied for tall stature (+3.8 SD), and was diagnosed as having GnRH-dependent precocious puberty due to a hypothalamic hamartoma of the tuber cinereum. He was treated with oral cyproterone acetate (110–170 mg/m2 daily) from 1.8 through 5.0 years of age, with oral cyproterone acetate and intranasal buserelin acetate (700–900 μg/m2 daily) from 5.0 through 7.5 years, and with intranasal buserelin acetate alone (1100– 1400 μg/m2 daily) from 7.5 through 12.6 years. He attained a final height of 171.0 cm at 14.9 years of age (+0.10 SD) and his twin 170.0 cm at 15.3 years of age (−0.10 SD), with their target height being 174.5 ± 9.0 cm. Conclusion This study indicates that GnRH analog treatment may preserve near full height potential in some patients with GnRH-dependent precocious puberty. Received: 30 March 1999 / Accepted: 31 May 1999  相似文献   
103.
Bone morphogenetic proteins (BMPs) are biologically active molecules capable of inducing new bone formation, and show potential for clinical use in bone defect repair. However, an ideal system for delivering BMPs that can potentiate their bone-inducing ability and provide initial mechanical strength and scaffold for bone ingrowth has not yet been developed. In this study, to construct a carrier/scaffold system for BMPs, we combined two biomaterials: interconnected-porous calcium hydroxyapatite ceramics (IP-CHA), and the synthetic biodegradable polymer poly D,L,-lactic acid-polyethyleneglycol block co-polymer (PLA-PEG). We used a rabbit radii model to evaluate the bone-regenerating efficacy of rhBMP-2/PLA-PEG/IP-CHA composite. At 8 weeks after implantation, all bone defects in groups treated with 5 or 20 microg of BMP were completely repaired with sufficient strength. Furthermore, using this carrier scaffold system, we reduced the amount of BMP necessary for such results to about a tenth of the amount needed in previous studies, probably due to the superior osteoconduction ability of IP-CHA and the optimal drug delivery system provided by PLA-PEG, inducing new bone formation in the interconnected pores. The present findings indicate that the synthetic biodegradable polymer/IP-CHA composite is an excellent combination carrier/scaffold delivery system for rhBMP-2, and that it strongly promotes the clinical effects of rhBMP-2 in bone tissue regeneration.  相似文献   
104.
Noonan syndrome (NS) is characterized by short stature, characteristic facial features, and heart defects. Recently, missense mutations of PTPN11, the gene encoding protein tyrosine phosphatase (PTP) SHP-2, were identified in patients with NS. Further, somatic mutations in PTPN11 were detected in childhood leukemia. Recent studies showed that the phosphatase activities of five mutations identified in NS and juvenile myelomonocytic leukemia (JMML) were increased. However, the functional properties of the other mutations remain unidentified. In this study, in order to clarify the differences between the mutations identified in NS and leukemia, we examined the phosphatase activity of 14 mutants of SHP-2. We identified nine mutations, including a novel F71I mutation, in 16 of 41 NS patients and two mutations, including a novel G503V mutation, in three of 29 patients with leukemia. Immune complex phosphatase assays of individual mutants transfected in COS7 cells showed that ten mutants identified in NS and four mutants in leukemia showed 1.4-fold to 12.7-fold increased activation compared with wild-type SHP-2. These results suggest that the pathogenesis of NS and leukemia is associated with enhanced phosphatase activity of mutant SHP-2. A comparison of the phosphatase activity in each mutant and a review of previously reported cases showed that high phosphatase activity observed in mutations at codons 61, 71, 72, and 76 was significantly associated with leukemogenesis.  相似文献   
105.
Aquaporins (AQPs) are water channel proteins that permit osmotically driven water movement. To determine their dynamics in pulmonary oedema, we examined the expression of mRNA and protein for AQP1, AQP3, AQP4, and AQP5 in the lungs of normal and thiourea-treated rats. In the thiourea group, lung water content increased significantly (vs. controls) with the peak at around 4 h. Semi-quantitative RT-PCR showed that AQP3 mRNA in the thiourea group rose significantly, peaking at around 4–8 h. The expression of AQP1, AQP4, AQP5, ENaC and CFTR mRNA each decreased significantly some time after the peak in lung water content. Immunoblot analysis showed that glycosylated AQP3 protein was increased 4–10 h after treatment. Expression of the other AQP proteins was not significantly altered, except for that of AQP4. Immunohistochemical examination revealed that AQP1 was expressed in endothelia, AQP3 in the basal cells of the large airways and in cuboidal cells in the bronchioles, AQP4 in the basolateral membrane of airway cells and AQP5 in type-I pneumocytes. Our results suggest that AQP3 is expressed not only in large airways, but also in bronchioles, and is related to water movement in pulmonary oedema.  相似文献   
106.
The aim of the present study was to investigate the possibility of integrating porous hydroxyapatite (HA) ceramics with a capillary vessel network via insertion of a vascular pedicle, and to determine whether this procedure enhances new bone formation in tissue engineering of bone. First, synthetic interconnected porous HA (IP-CHA) was implanted subcutaneously into rat groin with or without insertion of superficial inferior epigastric vessels. At 6 weeks, IP-CHA with vascular insertion contained thick fibrous connective tissue with a number of large blood vessels that seemed to derive from the inserted vascular bundle. Next, IP-CHA loaded with recombinant human bone morphogenetic protein 2 (BMP, 2 or 10 microg/block) was implanted with or without vascular insertion. At 3 weeks, IP-CHA/BMP (10 microg) composite with vascular insertion exhibited abundant new bone formation in the pores of the deep portion close to the inserted vessels. In contrast, IP-CHA/BMP (10 microg) without vascular insertion showed poor bone formation. Histomorphometric analysis demonstrated that vascular insertion significantly increased new bone formation. In IP-CHAs with a lower dose of BMP (2 microg), no bone formation was found, with or without vascular insertion. These results suggest that the present system of integrating a vascular network with IP-CHA is a useful technique for bone tissue engineering.  相似文献   
107.
A case Is presented of localized malignant peritoneal mesothelioma appearing as a liver neoplasm. The patient underwent tumor resection but developed a recurrent growth and died 10 months after the Initial surgery. The primary tumor showed sarcomatous features with rhabdoid cells. Examination revealed the presence of hyaluronic acid, co-Immunoreactivlty for cytokeratln epithelial membrane antigen and vlmentln, cellular contacts with small desmosomes, and intracytoplasmic lumina. These findings supported the mesothelial nature of this tumor. The recurrent tumor was composed of predominantly tubulopaplllary proliferation. It was concluded that the present tumor was a localized malignant mesothelioma of a blphasic type showing a predominantly sarcomatous component in the primary tumor.  相似文献   
108.
Several studies have reported that ovarian clear-cell adenocarcinoma can be derived from endometriosis. Although the clear-cell adenofibroma (CCAF), a major form of benign and borderline ovarian clear-cell tumour, has been suggested as another precursor for clear-cell adenocarcinoma (CCA), there is no supportive genetic evidence for this presumption. To examine the genetic linkage between CCAF and CCA of the ovary, we conducted allelotype analysis for both CCAF and adjacent CCA components in 14 cases of CCA associated with benign CCAF and/or borderline CCAF. DNA isolated from laser-microdissected tissue was subjected to polymerase chain reaction and analysis for loss of heterozygosity (LOH), using 17 polymorphic markers located on 11 chromosomal arms: 1p, 5q, 8p, 9p, 9q, 10q, 11q, 13q, 18q, 19p and 22q. For all informative loci, the frequency of LOH in adenocarcinoma was 49% (54/110 loci), and was significantly higher than those in the components of benign CCAF (22%, 20/92 loci) and borderline CCAF (30%, 25/83 loci) (chi(2) test; p<0.05, respectively). The concordance rate in allelic patterns at all informative loci was 74% between benign CCAF and adenocarcinoma components, 81% between borderline CCAF and adenocarcinoma components, and 95% between benign CCAF and borderline CCAF components. Furthermore, between CCAF and adenocarcinoma components, an identical LOH pattern, involving the same alleles, was found in 13 (93%) of 14 cases at one or more chromosomal loci, and estimation of probability indicated that these events were very unlikely to have occurred by chance. Among the markers examined, LOHs on 5q, 10q and 22q were frequent in both CCAF and adenocarcinoma components, whereas LOHs on 1p and 13q were rare in CCAF components but frequent in adenocarcinoma components. These findings suggest that CCAF can be a clonal precursor for ovarian clear-cell adenocarcinoma.  相似文献   
109.
Monoclonal antibodies (mAbs) are widely utilized as therapeutic drugs for various diseases, such as cancer, autoimmune diseases, and infectious diseases. Using the avian-derived B cell line DT40, we previously developed an antibody display technology, namely, the ADLib system, which rapidly generates antigen-specific mAbs. Here, we report the development of a human version of the ADLib system and showcase the streamlined generation and optimization of functional human mAbs. Tailored libraries were first constructed by replacing endogenous immunoglobulin genes with designed human counterparts. From these libraries, clones producing full-length human IgGs against distinct antigens can be isolated, as exemplified by the selection of antagonistic mAbs. Taking advantage of avian biology, effective affinity maturation was achieved in a straightforward manner by seamless diversification of the parental clones into secondary libraries followed by single-cell sorting, quickly affording mAbs with improved affinities and functionalities. Collectively, we demonstrate that the human ADLib system could serve as an integrative platform with unique diversity for rapid de novo generation and optimization of therapeutic or diagnostic antibody leads. Furthermore, our results suggest that libraries can be constructed by introducing exogenous genes into DT40 cells, indicating that the ADLib system has the potential to be applied for the rapid and effective directed evolution and optimization of proteins in various fields beyond biomedicine.  相似文献   
110.
We recently obtained 3 cloned cell lines demonstrating the p53 mutation from a lung metastatic nodule of a rat transplantable osteosarcoma. In this study, we applied wild-type p53 gene transfer to the rat osteosarcoma cells by lipofection to investigate the effects on cell growth, expression of genes such as waf1/p21, bcl-2, and bax, and nucleosomal DNA fragmentation due to apoptosis. Reconstitution of the p53 gene inhibits cellular growth, and this growth-suppressive effect is partly due to apoptosis involving bcl-2 gene suppression in this tumor type. This rat osteosarcoma model is similar in biologic behavior to human cases and thus is very suitable for further investigation of tumorigenesis and gene therapy for osteosarcoma.  相似文献   
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