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1.
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   
2.
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.  相似文献   
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Six heterogeneous common variable immunodeficiency (CVID) patients were analysed for germ-line DNA, DNA rearrangements, and RNA expressions of immunoglobulin (Ig) gene by Southern or northern blotting using appropriate probes. We detected no polymorphism in neutrophil DNA hybridized to a C mu and a C gamma probe. In three patients, both serum Ig and Ig-bearing cells were scarcely detected, and by northern hybridization methods, neither mu mRNA, gamma mRNA, alpha mRNA nor kappa mRNA was detected. However, one Epstein-Barr virus-transformed B lymphoblastoid cell line (LCL) of these three patients was different from the germ line in the region of JH, C gamma, and C kappa, and expressed mu mRNA at a higher level. The B cell defects of these three patients lay on the B cell maturation stage similar to X-linked agammaglobulinaemia (XLA). In two others among the six CVID patients, serum IgM and IgM-bearing cells were detected to a certain degree, and by northern hybridization, mu mRNA was detected at a lower level, but neither mu mRNA, alpha mRNA, nor kappa mRNA was detected. One LCL of these two patients could express mu mRNA at the normal level. In the last patient, the serum IgM was normal, serum IgG and IgA were somewhat low, Ig-bearing cells were normal, mu mRNA and kappa mRNA were detected at the normal level, and gamma mRNA and alpha mRNA were detected at a lower level. The defect of this patient affected the class switch stage. These results showed that primary B cell defects in CVID occurred at several B cell differentiation stages which could be classified by expression of the Ig gene, and at the degree of clonal diversity in the B cell repertoire. Furthermore, this study provides support for the idea that the CVID defect is related to a more generalized cellular function, such as regulating the proliferation and/or clonal expansion of cells of the B lymphoid lineage.  相似文献   
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The pathogenesis of cognitive impairment in alcoholics remains unclear. Previous studies suggested that diffuse white matter atrophy is associated with cognitive impairment in alcoholics. To elucidate this issue, the present study evaluated alcoholics with cognitive impairment using the somatosensory evoked potential (SEP) recovery method, which is suitable for detecting subtle dysfunction at the cortical level. Subjects comprised 12 alcoholics with mild cognitive impairment [Mild group: Mini Mental State Examination Score (MMSE), ≥24; mean, 27.9 ± 1.6], 12 alcoholics with moderate to severe cognitive impairment (Moderate group: MMSE score, < 24; mean, 21.0 ± 2.5) and 12 normal subjects (Control group). SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. Single-pulse or paired-pulse stimuli at various interstimulus intervals (10–300 ms) were administered. Recovery functions of N9 (a peripheral nerve component), N20, N20-P25 and P25-N33 (cortical components) were studied. N20 recovery curves of both alcoholic groups were less suppressive than those of Controls, and P25-N33 recovery curves of the Moderate group were more excitatory than those of the Mild or Control groups. A disinhibited recovery pattern of N20 indicates subcortical dysfunction, and a disinhibited pattern of P25-N33 would be induced by cortical dysfunction. Therefore, subcortical dysfunction indicated by an abnormal N20 recovery pattern may contribute to the early cognitive impairment of alcoholics, whilst the cortical dysfunction indicated by an abnormal P25-N33 recovery pattern may contribute to the later cognitive impairment of alcoholics.  相似文献   
7.
A 70-year-old female was found to have class V cytology on an endometrial smear, and a histological diagnosis of malignant lymphoma was made by endometrial biopsy. The pathological diagnosis was malignant lymphoma, diffuse large cell-type according to the Working Formulation classification. Immunohistochemical staining showed lymphoma cells to be positive for CD 20 (B 1), indicating B cell lineage. Two cervical lymph nodes were palpable, and swelling of a para-aortic lymph node was also found by abdominal CT scan. The clinical stage was determined to be III according to the Ann Arbor classification. After three courses of CHOP chemotherapy, lymphoma cells could no longer be detected by endometrial biopsy, and the para-aortic and cervical lymphadenopathy also disappeared. Primary malignant lymphoma of the uterus, especially of the uterine body, is very rare. Only eight cases of primary malignant lymphoma of the uterine body were reported in the literature. The cell lineage was decided in only one case, which was B cell type.  相似文献   
8.
An enzyme-linked immunosorbent assay (ELISA) system for the quantitation of human monocytic colony-stimulating factor (hM-CSF) was established, which was based on the "dual antibody immunometric sandwich" principle using horse and rabbit polyvalent antibodies against human urinary colony-stimulating factor (CSF-HU). The minimal detectable level of hM-CSF was 10 U/mL, and the assays showed good reproducibility. As measured by this method, the average serum hM-CSF level of 20 normal adults was 540 +/- 110 U/mL (range, 300 to 800 U/mL). The peak of hM-CSF measured by ELISA was identical to that measured by bioassay when semipurified CSF-HU was fractionated by reversed-phase high performance liquid chromatography (HPLC). This method detected two types of hM-CSF, which had approximate molecular weights of 85 Kd (CSF-HU) and 45 Kd in human serum and urine; the ratio of 85:45 Kd was very high in serum and the amounts of the two types were nearly equal in urine. After anticancer chemotherapy, the serum hM- CSF level of one half of the patients with hematological malignancy was elevated according to the reduction in neutrophil number, while it was almost in the normal range in the other half of the patients, indicating the possibility that anticancer chemotherapy damaged the hM- CSF-producing cells. This ELISA method may be useful for monitoring the serum hM-CSF level after anticancer chemotherapy.  相似文献   
9.
Human basophils were purified from normal peripheral blood, using density gradient followed by negative panning selection. We tested the effects of hemopoietic growth factors on the survival of these basophils in vitro. In the absence of exogenous factors, basophils (purity greater than 90%) decreased in number rapidly. At day 7 only 11% of the cells remained alive in cultures; less than 1% of cells survived at day 14. Interleukin (IL)-3 maintained numbers of viable cells; cell viability was 67% at day 7 and 45% at day 14. Granulocyte-macrophage (GM)-colony-stimulating factor (CSF) exhibited slight effect on the survival; 33% of cells remained at day 7. Other growth factors including granulocyte (G)-CSF, macrophage (M)-CSF, and IL-4 had no significant effect on the survival of basophils at all. Morphological and functional characterization of cells maintained by IL-3 revealed that they belonged to the basophil lineage. These observations indicate that normal basophils possess functional receptors for IL-3 and GM-CSF and that both factors modulate immediate- and delayed-type hypersensitivity reactions by prolonging the life span of basophils.  相似文献   
10.
Autotaxin (ATX), or nucleotide pyrophosphatase‐phosphodiesterase 2, is a secreted lysophospholipase D that generates bioactive phospholipids that act on G protein–coupled receptors. Here we show the expression patterns of the ATX gene in mouse and chicken embryos. ATX has a dynamic spatial and temporal expression pattern in both species and the expression domains during neural development are quite distinct from each other. Murine ATX (mATX) is expressed immediately rostral to the midbrain‐hindbrain boundary, whereas chicken ATX (cATX) is expressed in the diencephalon and later in the parencephalon‐synencephalon boundary. In the neural tube, cATX is expressed in the alar plate in contrast to mATX in the floor plate. ATX is also expressed in the hindbrain and various organ primordia such as face anlagen and skin appendages of the mouse and chicken. These results suggest conserved and non‐conserved roles for ATX during neural development and organogenesis in these species. Developmental Dynamics 236:1134–1143, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
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