CYTOMEGALOVIRUS OOPHORITIS WITH CORTICAL NECROSIS DURING REMISSION OF ACUTE LYMPHOCYTIC LEUKEMIA

Ovarian involvement of cytomegalovirus (CMV) is rarely observed in autopsy and biopsy materials. Cortical necrosis of the ovaries was found in an autopsy case with generalized CMV infection. The patient was an 11-year-old girl in a remission state of acute lymphocytic leukemia. Autopsy revealed several areas showing necrotic change up to 2 mm in size in the cortex of both ovaries. Many cytomegalic cells were found in both the necrotic and intact areas of the cortex. CMV had infected the granulosa, thecal and stromal cells as well as vascular endothelial cells. Oocytes of neither primary nor graafian follicles showed cytomegalic changes, although they were destroyed due to the necrosis. CMV antigen was immunohistologically detected in these cytomegalic cells. Ultrastructurally, herpesvirus-type particles were revealed in the nuclei and cytoplasm of the cytomegalic cells. This case demonstrated that ovarian infection with CMV can potentially induce cortical necrosis and decrease the number of oocytes. ACTA PATHOL JPN 38 : 1069 ∼ 1076, 1988.     

Expression of membrane-bound and soluble receptor activator of NF-kappaB ligand (RANKL) in human T cells

The receptor activator of NF-kappaB ligand (RANKL) and its receptor RANK are critical regulators for immune responses as well as bone remodeling. RANKL is a type II transmembrane protein that has two forms-a membrane-anchored protein and a secreted protein. In this report, we demonstrate for the first time the kinetical expression of two forms of RANKL in human T cells using two monoclonal antibodies (mAbs) against human RANKL, which we newly derived. Freshly isolated T cells rarely expressed mRANKL, while the activation of T cells induced a substantial but minimal level of mRANKL as well as the accumulation of considerable amounts of sRANKL. The addition of the metalloprotease inhibitor KB-R8301 efficiently suppressed the release of sRANKL from activated T cells or RANKL-transfectants, and reciprocally enhanced the mRANKL expression. The membrane form of RANKL was also expressed on the infiltrating T cells in the rheumatoid synovial fluid and in the gingival tissues of patients with periodontitis. Our results demonstrate that the expression of mRANKL on T cells is strictly limited, and the majority of RANKL protein produced by T cells may be active in the soluble form after shedding. The mAbs that were derived in this study may be useful for investigating the regulation and function of RANKL in immune responses and bone remodeling.     

Molecular basis of carotid body tumor and associated clinical features in Japan identified by genomic,immunohistochemical, and clinical analyses

Carotid body tumor (CBT) is classified as a paraganglioma (PGL). Here, we report the genetic background, protein expression pattern, and clinical findings of 30 Japanese CBT cases. Germline pathogenic or likely pathogenic (P/LP) variants of genes encoding succinate dehydrogenase subunits (SDHs) were detected in 15 of 30 cases (50%). The SDHB variants were the most frequently detected, followed by SDHA and SDHD variants. One case with SDHAF2 variant was bilateral CBT, and other two multiple PGL cases were not detected P/LP variants. The three cases with germline variants that could be tested did not have somatic P/LP variants of the same genes. Immunohistochemical analysis showed negative SDHB signals in CBT tissues in five cases with germline P/LP variants of SDHB, SDHD, or SDHA. In addition, SDHB signals in CBT tissues were negative in four of nine cases without germline P/LP variants of SDHs. These findings suggest the involvement of unidentified molecular mechanisms affecting SDHs.     

Effects of transforming growth factor-β1 on formation and activation of osteoclasts

Transforming growth factor-₁ (TGF-₁) has biological functions in various types of cells. However, its roles in the regulation of osteoclast formation and function are unclear. To examine them, we employed a culture system in which unfractionated cells obtained from long bones of 13-day-old mice were cultured on a dentine slice. We found that TGF-₁ has a potent inhibitory effect on osteoclastic bone resorption at a dose of 0.2–5 ng/ml. By electron microscopy the osteoclasts appeared to have fewer mitochondria and ruffled borders than those in control cultures. But in the presence of 1,25-dihydroxyvitamin D₃, [1,25-(OH)₂D₃], TGF-₁ at a dose of 0.2–1 ng/ml stimulated the formation of osteoclasts from unfractionated bone cell cultures in which preexistent osteoclasts had degenerated. Thus, using stromal cell-free he-mopoietic blast cells, we examined the direct action of TGF-₁ on osteoclast precursors. Although TGF-₁ inhibited tartrate-resistant acid phosphatase-positive (TRAP) multinucleate cell (MNC) formation induced by 1,25-(OH)₂D₃, the conditioned medium (CM) of TGF-₁-treated MC3T3-E1 cells stimulated such formation. These results suggest that TGF-₁ inhibits osteoclastic bone resorption but stimulates osteoclast formation via the action of factor(s) produced by TGF-₁-treated osteoblasts in the presence of 1,25-(OH)₂D₃.     

Disposition and metabolism of F6-1alpha,25(OH)2 vitamin D3 and 1alpha,25(OH)2 vitamin D3 in the parathyroid glands of rats dosed with tritium-labeled compounds.

26,26,26,27,27,27-Hexafluoro-1alpha,25(OH)2 vitamin D3, a hexafluorinated analog of 1alpha,25(OH)2 vitamin D3, has been reported to be several times more potent than the parent compound with respect to some vitamin D actions. The reason for enhanced biological activity in the bones, kidneys, and small intestine appears to be related to F6-1alpha,25(OH)2 vitamin D3 metabolism to ST-232 (26,26,26,27,27,27-hexafluoro-1alpha,23S,25-trihydroxyvitamin D3), a bioactive 23S-hydroxylated form that is resistant to further metabolism. We compared the disposition and metabolism of [1beta-3H]F6-1alpha,25(OH)2 vitamin D3 and [1beta-3H]1alpha,25(OH)2 vitamin D3 in parathyroid glands of rats intravenously administered with labeled compounds at a dose of 10 microg/kg. In the [1beta-3H]F6-1alpha,25(OH)2 vitamin D3-dosed group, radioactivity was highly detected in the kidneys, parathyroid glands, and the small intestine. The radioactivity in the parathyroid glands remained high until 48 h postdosing, with values of 2.5, 8.4, and 14.6 times higher at 6, 24, and 48 h postdosing than after dosing with [1beta-3H] 1alpha,25(OH)2 vitamin D3. In the group given [1beta-3H]F6-1alpha,25(OH)2 vitamin D3, the unchanged compound was mainly detected with a small amount of ST-232 at 6 h postdosing. At the 24- and 48-h time points, over half of the radioactivity was observed as ST-232, and additionally, ST-233, the 23-oxo form, accounted for a small amount at the 48-h time point. The present study demonstrated local retention of [1beta-3H]F6-1alpha,25(OH)2 vitamin D3 and the bioactive metabolite ST-232 in parathyroid glands after intravenous administration. The findings may indicate one of the reasons for the higher potency of F6-1alpha,25(OH)2 vitamin D3 than 1alpha,25(OH)2 vitamin D3 in parathyroid.     

In vitro drug-drug interactions with perospirone and concomitantly administered drugs in human liver microsomes.

In vitro metabolism studies were conducted to assess drug-drug interactions between perospirone, an antipsychotic agent, and concomitantly administered drugs--biperiden, flunitrazepam, haloperidol, and diazepam--using human liver microsomes. The metabolism of perospirone in the presence of 100 microg/ml drugs was decreased to 45-73% of that in their absence, whereas no effects were observed with any of the drugs at 1 microg/ml or lower. The effects of perospirone on the metabolism of concomitantly administered drugs were also assessed, and no inhibitory effect was observed. Thus, the metabolism of perospirone and concomitantly administered drugs did not demonstrate any marked mutual inhibition in the human liver microsomes. On the other hand, the perospirone metabolism was markedly reduced by ketoconazole indicating a major role for CYP 3A4. Based on the inhibition constant (Ki) for perospirone metabolism and the plasma unbound concentration of ketoconazole, in vivo perospirone clearance was estimated to be reduced to 64-90% of the control level. Thus careful attention should be paid to the possibility of increase in unchanged perospirone concentration when perospirone is co-administered with drugs that are known as CYP3A4 inhibitors, including macrolide antibiotics and other imidazole antifungals.     

A new simply and effective fractionation method for cylindrospermopsin analyses.

A new simply and effective fractionation method for cylindrospermopsin (CYN) analyses was developed. The extract from cells of Cylindrospermopsis raciborskii was resuspended with 0.1 M carbonate buffer at pH 10.5, and pass through the double-cartridges column which was consisted of a styrene polymer cartridge and an anion exchange cartridge. CYN and deoxy-CYN were adsorbed with the anion exchange cartridge. After separation of the anion exchange cartridge, adsorbed compounds were eluted from the cartridge with 50% methanol containing 1% formic acid solution. CYN and deoxy-CYN were selectively condensed in the eluted solution. When CYN was analyzed by LC-photodiode array or LC/MS, only two peaks of CYN and deoxy-CYN were detected quantitatively. The results suggest that the fractionation method is a useful method for CYN analyses and must be utilized for CYN purification.