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Osteoclastogenesis inhibitory factor (OCIF) is a novel secreted protein that inhibits osteoclastogenesis both in vitro and in vivo. In this study, we examined the effects of OCIF on serum calcium (Ca) concentrations in normal mice and in hypercalcemic nude mice carrying tumors associated with humoral hypercalcemia of malignancy. In normal mice, a single intraperitoneal injection of OCIF reduced serum Ca levels in a dose-dependent manner. Significant decrease in serum Ca (by 1.6 ± 0.3 mg/dL, n = 5) was observed 2 h after the injection of OCIF at 20 mg/kg and the hypocalcemic effect continued for up to 12 h. Serum phosphate (Pi) concentrations also decreased in response to OCIF. Urinary excretion of Ca, Pi, and creatinine did not change significantly after injection of OCIF or vehicle. In hypercalcemic, tumor-bearing nude mice, a single intraperitoneal injection of OCIF at 20 mg/kg resulted in a dramatic decrease in serum Ca (maximal decrease 2.8 ± 0.37 mg/dL, n = 11), which continued for up to 24 h. The results suggest that OCIF decreased serum Ca through its inhibitory effect on bone resorption. Furthermore, it is suggested that OCIF has therapeutic potential for the treatment of hypercalcemic conditions such as malignancy-associated hypercalcemia.  相似文献   
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The effects of spironolactone (5% SYC-201G, a preparation developed for clinical use in acne vulgaris by Searle Yakuhin K.K.), which is known to have antiandrogenic effects by competitively inhibiting dihydrotestosterone at androgen receptor sites, was topically applied to the androgen stimulated sebaceous glands of adult female golden hamsters. Androgen stimulation, induced by intramuscular injection of testosterone propionate (TP) every other day over a two week period, resulted in a 2.5 to 2.7 time increase in the size of the sebaceous glands of the hamster pinna. Once-daily treatment with 5% SYC-201G or matching placebo was applied to androgen-stimulated hamsters on one pinna only during the same period as TP injection. Comparison between the treated and untreated sides revealed a significant suppression in the sebaceous gland size (p<0.05) by 5% SYC-201G; no such effect was observed with placebo. The difference in the suppression rate of the sebaceous gland size between 5% SYC-201G (23%) and matching placebo (–4.7%) was significant (p<0.01).  相似文献   
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Immunosuppressive activities of the newly discovered FK506, isolated from Streptomyces tsukubaensis, were examined by using cardiac allotransplantation in the rat, and the mechanisms underlying induction and maintenance of FK506-induced long-term allograft survival were studied. Male rats of WKA (RT1k) and F344 (RT1lvl) strains were used as recipients and donors, respectively, and those of BN (RT1n) strain were used as third-party donors. Treatment with FK506, beginning from the day of allografting for 14, 10, or as few as 4 days, prolonged allograft survival significantly across the major histocompatibility barrier. The minimum doses for prolonging graft survival were 0.1 mg/kg/day by intramuscular treatment and 1.0 mg/kg/day by oral treatment. Treatment with FK506 at a dose of 0.32 mg/kg/day from day 4 until day 10 resulted in all the grafts surviving indefinitely and from days 5 to 10, half the grafts survived indefinitely, suggesting that the agent inhibited ongoing rejection. On the other hand, cyclosporine treatment at a dose of 20 mg/kg/day from day 2 did not prolong graft survival time statistically significantly. Induction of prolonged graft survival was not obtained by pretreatment of the prospective donor or recipient; prolonging effects were observed only when the agent was administered after allografting. Thus, the primary effect of the agent is exerted on responder lymphocytes reacting to the donor antigens in the induction phase of long-term graft acceptance. The mechanisms underlying the maintenance of long-term grafts were analyzed by testing the capacity of lymphocytes or serum of long-term graft-bearing rats to inhibit graft rejection in irradiated grafted hosts. Transfer of 2 x 10(8) lymphocytes from FK506-induced long-term F344 graft-bearing WKA rats resulted in indefinite survival of F344 heart allografts, but it did not prolong survival of third-party BN hearts. Transfer of 2.5 ml serum from long-term graft-bearing rats also prolonged graft survival of F344 hearts, but not BN hearts. These results suggest that donor strain-specific suppressor cells and humoral factor(s) are induced by treatment with FK506 in the presence of allografts, and that they play at least partial roles in the maintenance of long-term allograft acceptance.  相似文献   
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Background: The authors previously reported that, during isoflurane anesthesia, electroencephalographic bicoherence values changed in a fairly restricted region of frequency versus frequency space. The aim of the current study was to clarify the relation between electroencephalographic bicoherence and the isoflurane concentration.

Methods: Thirty elective abdominal surgery patients (male and female, aged 34-77 yr, American Society of Anesthesiologists physical status I-II) were enrolled. After electroencephalogram recording with patients in an awake state, anesthesia was induced with 3 mg/kg thiopental and maintained with oxygen and isoflurane. Continuous epidural anesthesia with 80-100 mg/kg 1% lidocaine was also administered. Using software they developed, the authors continuously recorded the FP1-A1 lead of the electroencephalographic signal and expired isoflurane concentration to an IBM-PC compatible computer. After confirming the steady state of each isoflurane (end-tidal concentration at 0.3, 0.5, 0.7, 0.9, 1.1, 1.3, and 1.5%), electroencephalographic bicoherence values were calculated.

Results: In a light anesthetic state, electroencephalographic bicoherence values were low (generally <= 15.0%). At increased concentrations of isoflurane, two peaks of electroencephalographic bicoherence emerged along the diagonal line (f1 = f2). The peak emerged at around 4.0 Hz and grew higher as isoflurane concentration increased until it reached a plateau (43.8 +/- 3.5%, mean +/- SD) at isoflurane 0.9%. The other peak, at about 10.0 Hz, also became significantly higher and reached a plateau (32.6 +/- 9.2%) at isoflurane 0.9%; at isoflurane 1.3%, however, this peak slightly decreased.  相似文献   

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In lung cancer patients, hypercalcemia is a fairly common metabolic problem associated with malignancy. However, the occurrence of hypercalcemia in lung cancer patients means an ominous prognostic sign. As hypercalcemia often causes early death, quick diagnosis and treatment for hypercalcemia are required. A 69-year-old woman was admitted to our hospital with anorexia caused by hypercalcemia. On admission, serum level of PTH was elevated and PTHrP was normal. From the results of CT findings and transbronchial lung biopsy, the cause of the hypercalcemia was determined as lung cancer incidentally complicated with primary hyperparathyroidism. First, serum calcium level was returned to normal through hydration with saline and bisphosphonates. Next, left hemithyroidectomy for primary hyperparathyroidism was performed. Histologically, the tumor was diagnosed as parathyroid adenoma. Fifteen days later, left lower lobectomy for primary lung cancer was performed under a video-assisted thoracoscopic approach. Histologically, the tumor was diagnosed as a moderately differentiated adenocarcinoma. Four years and three months after the operation, the patient is alive and well with no sign of recurrence. When a lung cancer patient is complicated with hypercalcemia, we need to consider that primary hyperparathyroidism is a possible cause of the hypercalcemia.  相似文献   
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