Effect of magnetic field on pineal gland volume and pinealocyte size in the rat

Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat.     

A case of autoimmune hepatitis needed to be differentiated from EBV hepatitis, in that the histology of liver biopsy specimen was useful for diagnosis]

A 10-year-old girl with autoimmune hepatitis (AIH) was reported. She was admitted to our hospital because of cholestasis and elevation of liver enzymes for 2 months. Laboratory examination revealed that EBV-DNA copy number in the PBMNC (peripheral mononuclear cells) was 1.2 x 10(3) copies/microg of DNA, hypergammaglobulinemia, and positive antinuclear antibody, positive anti-smooth muscle antibody. The histology of her liver biopsy specimen revealed interface hepatitis, dense mononuclear cell infiltrates, mild fibrosis, and negative for EBV in situ hybridization assay indicating AIH and not EBV-associated hepatitis. She was treated firstly with methylprednisolone pulses, then will prednisolone p.o.+azathioprine p.o.. Intravenous cyclophosphamide pulse therapy was introduced because of her abnormal immune pathology. All abnormal laboratory parameters improved to normal levels within 2 months, and EBV-DNA copy number in the PBMNC became negative after 4 months. The histology of liver biopsy specimen was useful for the diagnosis of AIH in such a difficult case needed to be differentiated from EBV hepatitis.     

Effects of Zinc on Production of Active Oxygen Species by Rat Neutrophils

Abstract: The effects of zinc on the production of active oxygen species were investigated in rat neutrophils by chemilumi-nescence and spectrophotometric assays. The luminol-dependent chemiluminescence in unstimulated neutrophils showed a single peak. Zinc at concentrations lower than 0.1 mM augmented the intensity of chemiluminescence and showed a bimodal pattern, the first peak of which was inhibited by superoxide dismutase and catalase, while the second peak disappeared in the presence of catalase, but was unaffected by superoxide dismutase. At the same concentrations of zinc, O₂^? and H₂O₂ production increased, but secretion and activity of myeloperoxidase were not affected. Zinc at 0.1 mM enhanced the second peak of luminol-dependent chemiluminescence, and concomitantly O₂^? and H₂O₂ production of neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine. Homogenized neutrophils showed a bimodal pattern on induction by zinc, the second peak of which was inhibited slightly by catalase and completely by sodium azide, but was not inhibited by superoxide dismutase. Zinc-induced O₂^? production was inhibited by pertussis toxin, but was not significantly inhibited by a protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), or a calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). These results suggest that zinc can augment luminol-dependent chemiluminescence by increasing O₂^? production through the classical signal transduction pathway, and by increasing H₂O₂ not via O₂^?.     

Universal applications of sentinel node technology

The sentinel node (SN) concept was originally proposed by several pioneers in the middle of the last century. After Donald Morton and his colleagues demonstrated the clinical significance of the SN concept in melanoma, it attracted vast attention in surgical oncology. At recent international conferences, a number of new approaches in this field for various solid tumors have been reported. Now, there are several possible applications with different technological aspects, such as individualized surgical management of solid tumors, multidisciplinary treatments, and novel therapeutic approaches. This article provides an overview of the future potential of SN technology.     

A case of mixed connective tissue disease successfully treated for hemophagocytic syndrome with intermittent intravenous injection of cyclophosphamide]

A 52 year-old woman noticed general fatigue, polyarthralgia, and muscle weakness of lower extremities in October 2001. In December, she felt difficulty in walking due to muscle weakness. In January 2002, she admitted another hospital because of dyspnea on exertion and edema of lower extremities. Laboratory test revealed leukocytopenia, the elevation of creatine kinase and positive anti-U1-RNP antibodies. Her chest computed tomography (CT) showed severe interstitial pneumonia. Cardiac echogram revealed that she had pericardial effusion and pulmonary hypertension. Then she was transferred to Keio University Hospital and she was diagnosed as having mixed connective tissue disease (MCTD) manifestating myositis, interstitial pneumonia, pulmonary hypertension and pericarditis. Prednisolone (PSL) 60mg daily following to methylprednisolone (mPSL) pulse therapy was begun and her symptoms were gradually improved. In middle of February, she complained of high fever over 39.0 degrees C. Bacterial culture tests were negative and laboratory data indicated pancytopenia and a high level of serum ferritin. Bone marrow aspiration revealed hemophagocytosis in bone marrow specimens and she was diagnosed as having hemophagocytic syndrome associated with MCTD. mPSL pulse therapy was not effective and intermittent cyclophosphamide pulse therapy (IV-CY) was performed resulting in improvement of the symptoms. This case suggested the effectiveness of IV-CY therapy in patients with corticosteroid-resistant HPS associated with connective tissue diseases.     

Applications of DNA Flow Cytometry and Fluorescence In situ Hybridization Using a Chromosome-specific DNA Probe on Paraffin-embedded Tissue Sections of Primary Malignant Melanomas

We have applied DNA flow cytometric analysis to paraffin-embedded tissue sections of primary malignant melanomas. Conventionally, flow cytometric analysis of paraffin-embedded tissue sections has been done by the method of Hedley et al. We added ultrasound treatment to the method of Hedley et al. and a lower value of coefficient of variation was shown. Furthermore, a new technique, fluorescence in situ hybridization with a chromosome-specific repetitive DNA probe, was used for the analysis of chromosomal numerical aberrations in the same paraffin-embedded tissue sections. The DNA flow cytometric analysis showed that in 8 cases six primary malignant melanomas were of the aneuploid pattern and two cases of lentigo maligna (melamona in situ) were of the diploid pattern. By fluorescence in situ hybridization, the two cases with the diploid pattern had spots/nucleus of 1.28 and 1.12, and those with the aneuploid pattern had spots/nucleus from 2.01 to 2.27. Only one nodular melanoma in an aneuploid case showed spots/nucleus of 1.71. These data indicate that fluorescence in situ hybridization with chromosome-specific repetitive DNA probes can serve as a cytogenetic tool for the analysis of interphase nuclei of solid human tumors and may be useful for the study of tumor cell heterogeneity.