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71.
A squamous cell carcinoma of 33-yr-old patient who developed marked leukocytosis and hypercalcemia was transplanted into nude mice in which more marked leukocytosis and hypercalcemia also developed. This tumor (LJC-1-JCK) produced a colony-stimulating factor (CSF) and formed a cyst in the tumor from which a CSF-producing cell line (T3M-1) was established. The CSF causes predominantly formation of granulocytic colonies in addition to macrophage colonies. Bone-resorbing activity (BRA) was detected in the cystic fluid and was eluted as two separate peaks with proteins of an apparent molecular weight of 30,000-50,000 and 10,000-20,000. Colony-stimulating activity (CSA) was eluted at an apparent 30,000 mol wt. The conditioned medium of the T3M-1 cells also contained a BRA with an apparent 14,000 mol wt, whereas CSA eluted at an apparent 30,000 mol wt. PTH, epidermal growth factor, transforming growth factor-alpha, prostaglandin Es, and vitamin D could not account for the powerful BRA. In contrast to CSA, BRA was not inactivated by trypsin and more stable at 70 degrees C. When T3M-1 cells were transplanted into nude mice, marked hypercalcemia developed in addition to granulocytosis. Our findings suggest that the tumor produces and secretes a powerful BRA in vivo and in vitro, which is different from CSA in terms of molecular weight, heat stability, and trypsin treatment. We speculate that the synergistic action of CSF that stimulates macrophage colony formation and recruits osteoclast precursors, and BRA, which stimulates mononuclear phagocytes and/or osteoclasts were responsible for a marked increase in osteoclastic bone resorption and humoral hypercalcemia in the patient.  相似文献   
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Thymic epithelial cell lines (TECs) were established from newborn C57BL/6 mice. They were classified into two types (medullary and cortical TECs) by using the monoclonal antibody (Th-3) that recognizes the meshwork structure of thymic cortical epithelial cells. Antigen-presenting activity of each TEC was determined by using ovalbumin-specific, I-Ab-restricted helper T cell lines. It was demonstrated that the medullary but not the cortical TECs functioned as antigen-presenting cells. This is the first evidence for the functional difference between the cortical and the medullary TEC.  相似文献   
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Introduction

Posttransplant lymphoproliferative disorder (PTLD) is one of the severe complications after pediatric liver transplantation. Epstein-Barr virus (EBV) infection is a major risk factor developing PTLD. This study evaluates the risk factors, incidence, and clinical presentation of EBV infection at our institute.

Patients and Methods

This study examines 81 children who underwent living-related liver transplantation (LRLT) from November 2005 to December 2009. The immunosuppression protocol consisted of tacrolimus and low-dose steroids, which were withdrawn by 3 months after LRLT. Additional immunosuppression was indicated for the selected cases because of recurrent rejection or renal insufficiency. Fifteen ABO blood type incompatible LRLTs were enrolled into this study. EBV was periodically monitored by the use of a real-time quantitative polymerase chain reaction (cut-off value, >102 copies/μg DNA). The median follow-up period was 637 days (range, 85 to 1548 days). These patients were divided into two groups: EBV infection versus EBV noninfection, for analysis of risk factors by univariate analysis.

Results

The incidence of EBV infection was 50.6% (n = 41) with the mean onset of 276 ± 279 postoperative days (range, 7 to 1229 days). Nine cases (22.5%) presented clinical symptoms related to EBV infection, consisting of adenoid hypetrophy (n = 5), Evans's syndroms (n = 2), hemophagocytic syndrome (n = 1), and erythema nodosum (n = 1). There was no case of PTLD. The combination of a preoperative EBV seropositive donor and an EBV seronegative recipient was a high risk factor for postoperative EBV infection among the recipients (56.1% versus 26.8%, P < .05). The mean age at operation among the EBV infection group was younger than that of the EBV noninfection group (22 ± 30 months versus 62 ± 68 months; P < .05). The incidence of acute rejection episodes and cytomegalovirus infections; ABO blood type incompatible LRLT, and the length of steroid treatment and the additional immunosuppression were not significantly different between the two groups.

Conclusion

There were various clinical presentations related to EBV infection; however, none of our patients developed PTLD. Careful monitoring of EBV infection especially for cases with donor seropositivity is important to prevent disease progression.  相似文献   
74.
The stem of the Akebia plant, “Mokutsu”, is a crude diuretic and antiphlogistic drug. Japanese products prepared from wild Akebia plants cover most of the Mokutsu market. Two Akebia plants, Akebia quinata Decaisne (Aq) and A. trifoliata Koidzumi (At) of Lardizabalaceae, are standardized as Mokutsu in Japanese pharmacopoeia. These two Akebia plants along with A. × pentaphylla Makino (Ap), which is considered a hybrid with the morphology of Aq and At, can be distinguished by DNA sequence analysis of internal transcribed spacers 1 and 2 (ITS) of nuclear ribosome DNA. Here, we report the results of molecular genetic analysis of Akebia plants grown in various wild habitats in Japan. We found that each of three Akebia plants could be distinguished in terms of their locality according to their nucleotide sequence in ITS, specifically at positions 91, 128, 133, 134, and 221. Plants with a comparable habitat had similar nucleotide sequences at these five points. We also found Aq with ITS and nucleotide deletion at position 86 that was distributed only around Awajishima in Shikoku (A), Harimanada (B), and Kinki (C), including the chief production center of Akebia Caulis. The results of these ITS sequences enabled discrimination of plants originating from Akebia Caulis.  相似文献   
75.
Programmed cell death, or apoptosis, is an essential event in animal development. Spatiotemporal analysis of caspase activation in vivo could provide new insights into programmed cell death occurring during development. Here, using the FRET-based caspase-3 indicator, SCAT3, we report the results of live-imaging analysis of caspase activation in developing Drosophila in vivo. In Drosophila, the salivary gland is sculpted by caspase-mediated programmed cell death initiated by the steroid hormone 20-hydroxyecdysone (ecdysone). Using a SCAT3 probe, we observed that caspase activation in the salivary glands begins in the anterior cells and is then propagated to the posterior cells in vivo. In vitro salivary gland culture experiments indicated that local exposure of ecdysone to the anterior salivary gland reproduces the caspase activation gradient as observed in vivo. In betaFTZ-F1 mutants, caspase activation was delayed and occurred in a random pattern in vivo. In contrast to the in vivo response, the salivary glands from betaFTZ-F1 mutants showed a normal in vitro response to ecdysone, suggesting that betaFTZ-F1 may be involved in ecdysteroid biosynthesis and secretion of ecdysone from the ring gland for local initiation of programmed cell death. These results imply a role of betaFTZ-F1 in coordinating the initiation of salivary gland apoptosis in development.  相似文献   
76.
Purpose To evaluate the feasibility and safety of withdrawal of a Gunther tulip retrievable vena cava filter (GTF). Methods Between June 2001 and December 2005, at our institution 86 GTFs were implanted for temporary caval filtration in 59 patients (37 women, 22 men; mean age 59.3 years, range 18–87 years). For GTFs retrieved thereafter, we retrospectively reviewed the following parameters: rate of success in retrieval, degree of trapped thrombus in the filter, and complications during retrieval. Results Worsening of or new development of pulmonary embolism after filter implantation did not occur in any patient. Of the 86 GTFs implanted, retrieval of 80 was attempted. Among those 80 filters, 77 (96%) were successfully retrieved (with the standard method, n = 72; with the modified method, n = 5) without any complication. The period of implantation of the retrieved filters was 13.4 ± 4.2 days. In the 5 filters that were filled to a height of ≥ 1/4 with trapped thrombus, retrieval was performed after attempts were made to decrease trapped thrombi. In addition, a temporary filter or another GTF was temporarily placed at the cephalad level of the GTF during this removal procedure. Conclusion GTFs can be retrieved in the majority of cases. Even when encountering situations in which the filter could not be removed using the standard method, withdrawal was possible in a high frequency of cases through various trials using modified methods.  相似文献   
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