Rotatable Offner imaging system for ellipsometric measurement.

To realize high spatial resolution imaging ellipsometric measurement with large field of view, we developed a rotatable Offner system with unit magnification. When the conventional Offner imaging system is tilted relative to the sample plane for the ellipsometric measurement, only a small region of plane is in focus. The rotatable Offner system developed here renders the entire object in focus through all rotations. The performance of the prototype of the Offner system and imaging ellipsometer is tested by generating maps of the ellipsometric parameters Δ and Ψ for samples such as a silicon wafer and a resolution target made of chromium film evaporated on a glass substrate.

Differential expression and the anti-apoptotic effect of human placental neurotrophins and their receptors.

Neurotrophin (NT) is important in the survival, maintenance and differentiation of neuronal tissue, and functions in follicle maturation, tumor growth, angiogenesis and immunomodulation; however, the expression of NT and its receptors (NTR) in human placenta and their influence on fetal growth are unclear. Here we investigated the correlation of NT and NTR in human placenta with uterine environment and fetal growth. TrkB, a NTR, mRNA was expressed on decidual and villous tissue and increased with gestational age, localizing in the trophoblast layer and endothelium by immunohistochemistry. Villous TrkB mRNA was significantly increased in preeclampsia (PE) than in controls and was higher in the normotensive small for gestational age (SGA) placenta, although it was not significant. It was also significantly increased in the small twin of discordant twin pregnancies. Brain-derived neurotrophic factor (BDNF), the main ligand of TrkB, was expressed in membranous chorion and villous tissue and was significantly higher in maternal plasma in normotensive SGA and PE than in controls. TrkB mRNA expression was up-regulated on cultured villous tissue explants and on JEG-3, a choriocarcinoma cell line, by H(2)O(2) treatment. BDNF decreased apoptotic cells in H(2)O(2)-treated JEG-3, indicating that BDNF/TrkB signaling had anti-apoptotic effects against oxidative stress in JEG-3, suggesting a protective role of BDNF/TrkB in human villous tissue under unfavorable conditions in utero.

Branched-chain amino acid supplemented diet during maternal food restriction prevents developmental hypertension in adult rat offspring.

Maternal food restriction is known to cause developmental hypertension in offspring. We have previously shown that maternal high-protein diet can reverse fetal programming of hypertension and that branched-chain amino acid (BCAA) concentrations in maternal and fetal plasma were increased by maternal high-protein intake. Then, we hypothesized that isocaloric supplementation with BCAA to a maternal food restriction can reverse the adverse outcome. Pregnant rats were divided into four groups at 7.5 days postcoitum: normally nourished (NN) and 70% undernourished (UN) groups with and without BCAA supplementation (NN-standard diet (SD), NN-BCAA, UN-SD and UN-BCAA groups). Compared with pups in the NN groups, those in the UN-SD group had significantly increased systolic blood pressure (SBP) at 8 and 16 weeks of age (P < 0.05). However, the elevation of SBP was not observed in offspring in the UN-BCAA group. Offspring glomeruli number of the UN groups was significantly lower (P < 0.05) than that of the NN groups, independent of BCAA supplementation. Angiotensin II receptor type 2 (ATR2) mRNA and protein expression in the kidney was significantly augmented in the UN-BCAA group at 30 weeks of age. In conclusion, BCAA supplementation during maternal food restriction prevents developmental hypertension together with increased ATR2 expression in adult offspring kidney.

Epigenetic regulation of CD133 and tumorigenicity of CD133+ ovarian cancer cells.

The cancer stem cell hypothesis posits that malignant growth arises from a rare population of progenitor cells within a tumor that provide it with unlimited regenerative capacity. Such cells also possess increased resistance to chemotherapeutic agents. Resurgence of chemoresistant disease after primary therapy typifies epithelial ovarian cancer and may be attributable to residual cancer stem cells, or cancer-initiating cells, that survive initial treatment. As the cell surface marker CD133 identifies cancer-initiating cells in a number of other malignancies, we sought to determine the potential role of CD133+ cells in epithelial ovarian cancer. We detected CD133 on ovarian cancer cell lines, in primary cancers and on purified epithelial cells from ascitic fluid of ovarian cancer patients. We found CD133+ ovarian cancer cells generate both CD133+ and CD133- daughter cells, whereas CD133- cells divide symmetrically. CD133+ cells exhibit enhanced resistance to platinum-based therapy, drugs commonly used as first-line agents for the treatment of ovarian cancer. Sorted CD133+ ovarian cancer cells also form more aggressive tumor xenografts at a lower inoculum than their CD133- progeny. Epigenetic changes may be integral to the behavior of cancer progenitor cells and their progeny. In this regard, we found that CD133 transcription is controlled by both histone modifications and promoter methylation. Sorted CD133- ovarian cancer cells treated with DNA methyltransferase and histone deacetylase inhibitors show a synergistic increase in cell surface CD133 expression. Moreover, DNA methylation at the ovarian tissue active P2 promoter is inversely correlated with CD133 transcription. We also found that promoter methylation increases in CD133- progeny of CD133+ cells, with CD133+ cells retaining a less methylated or unmethylated state. Taken together, our results show that CD133 expression in ovarian cancer is directly regulated by epigenetic modifications and support the idea that CD133 demarcates an ovarian cancer-initiating cell population. The activity of these cells may be epigenetically detected and such cells might serve as pertinent chemotherapeutic targets for reducing disease recurrence.

Association between polymorphisms of folate- and methionine-metabolizing enzymes and susceptibility to malignant lymphoma.

Genetic alteration is considered a probable cause of malignant lymphoma. Folate and methionine metabolism play essential roles in DNA synthesis and DNA methylation, and their metabolic pathways might thus affect disease susceptibility. In the present study, 2 polymorphisms were evaluated for a folate metabolic enzyme, methylenetetrahydrofolate reductase (MTHFR), and one was evaluated for methionine synthase (MS). The 2 polymorphisms, MTHFR677 C-->T and MTHFR1298 A-->C, are reported to reduce the enzyme activity, which causes intracellular accumulation of 5,10-methylenetetrahydrofolate and results in a reduced incidence of DNA double-strand breakage. The MS2756 A-->G polymorphism also reduces the enzyme activity and results in the hypomethylation of DNA. To evaluate the association between malignant lymphoma susceptibility and these polymorphisms, hospital-based case-control study was conducted in Aichi Cancer Center. Ninety-eight patients with histologically confirmed lymphoma and 243 control subjects without cancer were evaluated. Unconditional logistic regression analyses revealed a higher susceptibility with the MTHFR677 CC and the MTHFR1298 AA genotypes (odds ratio, 2.26; 95% confidence interval, 1.26-4.02) when those harboring at least one variant allele in either polymorphism of MTHFR were defined as the reference. For the MS polymorphism, the MS2756 GG genotype also showed a higher susceptibility (odds ratio, 3.83; 95% CI, 1.21-12.1) than those with MS2756 AA or AG types. The significance was not altered when these 3 polymorphisms were evaluated in combination, and the results suggest that folate and methionine metabolism play important roles in the occurrence of malignant lymphomas. Further studies to confirm the association and detailed biologic mechanisms are now required.

[Development of cerebellar astrocytoma in a patient with acute myeloid leukemia 8 years after his second bone marrow transplant].

We report a case of cerebellar astrocytoma occurring 8 years after the second bone marrow transplantation (BMT) in 32-year-old man. The patient was admitted to our hospital in December 1997 because of dysarthria and gait disturbance. He had been treated earlier for acute myeloid leukemia (AML M2) with chemotherapy and cranial irradiation followed by allogeneic BMT from a sibling in december 1988. Three months after the first BMT, testicular relapse was observed and followed by systemic relapse. The patient received reinduction therapy and a second successful BMT. He had been well until about 1 month before admission to our hospital. Neurological examination revealed left cerebellar ataxia, and brain magnetic resonance imaging disclosed a left cerebellar tumor. The tumor was surgically resected and a histological diagnosis of cerebellar astrocytoma was made. The patient was further treated by irradiation for residual tumor and discharged without progression of the disease.

Characterization of a novel human natural killer-cell line (NK-YS) established from natural killer cell lymphoma/leukemia associated with Epstein-Barr virus infection.

A novel cell line was established from a patient with a leukemic-state nasal angiocentric natural killer (NK) cell lymphoma with systemic skin infiltration. The morphology of the leukemic cells was large-granular-lymphocyte (LGL), and their immunophenotype was CD2+, CD3-, CD5+, CD7+, CD16-, CD56+, and CD57-. The presence of Epstein-Barr viral (EBV) genome was shown in specimens from the patient's nose, skin, and peripheral blood by in situ hybridization using an EBV-encoded small RNA-1 probe or by Southern blotting using a terminal-repeat probe of the EBV genome. Leukemic cells were cocultured with a mouse stromal cell line (SPY3-2) in the presence of 100 U/mL recombinant human interleukin-2 and a novel stromal cell-independent cell line, NK-YS, was established. The NK-YS cells showed LGL morphology and expressed surface CD2, CD5, CD7, CD25, CD56, and CD95. The NK-YS cells retained cytotoxicity against K562 and Jurkat cells. A Southern blotting using a terminal-repeat probe of EBV showed that NK-YS and fresh leukemic cells had a clonal EBV genome, whereas the T-cell receptor beta and gamma chain genes of NK-YS were not rearranged. In an immunocytochemical analysis, the NK-YS cells showed a type-II latent infection of EBV. The NK-YS cells preserved the original characteristics of NK cell lymphoma/leukemia and will be a useful tool for the study of biological characteristics of EBV-associated nasal angiocentric NK cell lymphoma/leukemia.

Induction of different types of glomerulonephritis by monoclonal antibodies derived from an MRL/lpr lupus mouse.

MRL/Mp-lpr/lpr(MRL/lpr) lupus mice develop glomerulonephritis in which the histopathological manifestations of the disease are characterized by diffuse cell-proliferative, crescentic, and/or wire loop-like lesions, resembling those of human lupus nephritis. Although these lesions are thought to be mediated by antibodies, little data is available to explain these regular variations in glomerular lesions induced by antibodies at the monoclonal level. We studied glomerular lesions of normal or severe combined immunodeficient mice injected with nephritogenic immunoglobulin G3-producing hybridoma clones (2B11.3 and 7B6.8), which we previously established from an unmanipulated MRL/lpr mouse. Both clones caused increased serum levels of immunoglobulin G3 with identical patterns over time and both induced glomerular deposits of immunoglobulin G3 and C3. However, 2B11.3 and 7B6.8 induced glomerular lesions that differed in their histopathological manifestations. The 2B11.3 clone generated cell-proliferative lesions associated with marked Mac-2-positive macrophage infiltrates, but the 7B6.8 clone induced lesions characterized by subendothelial hyaline deposits resembling wire loops. The latter was not associated with significant inflammatory cell infiltrates at any point throughout the progression of the lesion. Thus, our findings suggest that the histopathological variation in glomerulonephritis seen in MRL/lpr mice results from clonally expanded B cell clones that produce nephritogenic antibodies with different pathogenic potencies.