Distribution and sequence of pyknotic cells in rat fetuses exposed to busulfan.

Busulfan, an antineoplastic bifunctional-alkylating agent, is known to induce developmental anomalies. In the present study, we examined the distribution and sequence of pyknotic cells in rat fetal tissues exposed to busulfan. Pregnant rats on gestation day 13 were administered intraperitoneally 30 mg/kg of busulfan, and fetal tissues were examined at 6, 12, 24, 36, 48, 72 and 96 hours after treatment (HAT). Pyknosis of component cells was observed markedly in the brain, moderately in the eyes and spinal cord and mildly in the craniofacial tissue, mandible, limb buds, tail bud, ganglions, alimentary tract, lungs, kidneys, pancreas and liver. In the brain, mitotic inhibition was also detected. Most of the pyknotic cells were considered to be apoptotic cells judging from the results of TUNEL staining and electron microscopic examination. Commonly in the above-mentioned tissues, pyknotic cells began to increase at 24 HAT, peaked at 36 or 48 HAT and disappeared at 96 HAT, which is when the histological picture returned to normal in most tissues except for the brain, spinal cord and eyes. The present study clarified the outline of busulfan-induced apoptosis in rat fetuses.

Small cell variant of T-cell prolymphocytic leukemia with a gammadelta immunophenotype.

T-cell prolymphocytic leukemia (T-PLL) is a rare postthymic T-cell disorder. The disease is characterized by lymphadenopathy, splenomegaly, skin lesions, a high white blood cell count, and an aggressive clinical course. The small cell variant of T-PLL occurs in approximately 20% of patients. Most T-PLL patients express membrane T-cell receptors (TCR) of the alphabeta phenotype. The diagnosis of small cell variant T-PLL in a 56-year-old woman was based on the findings of abnormal lymphocytosis, immunophenotype, lymphadenopathy, and aggressive clinical behavior. Immunophenotype analysis showed that lymphocytes were positive for CD2, CD3, CD5, CD7, CD8, and TCR gammadelta antigens and negative for CD1a, CD4, and TCR alphabeta antigens. Southern blot analysis revealed rearrangement of the TCR Jgamma and Jdelta-1 genes. A cytogenetic study of peripheral blood showed a normal karyotype. T-PLL with a TCR gammadelta phenotype is very rare. This case was typical T-PLL except for the morphologically small cell type and the lack of the typical chromosome aberration. If cases accumulate in the future, the specific features of the gamma8 type of T-PLL will become clearer.

T-cell prolymphocytic leukemia with hemorrhagic gastrointestinal involvement and a new chromosomal abnormality.

We report a case of T-cell prolymphocytic leukemia in a 56-year-old woman who exhibited hemorrhaging with gastric involvement as the first manifestation. This patient's condition was diagnosed as T-cell prolymphocytic leukemia based on the findings of lymphocytosis, abnormal immunophenotype, hepatosplenomegaly, lymphadenopathy, and cutaneous involvement. Endoscopic examination of the upper gastrointestinal tract revealed hemorrhage from a gastric lesion with histological involvement. Cytogenetic analysis revealed chromosomal abnormalities, 46,XX,der(1), add(1)(p36), that have not previously been described in T-cell prolymphocytic leukemia. In spite of a transient response to chemotherapy, the patient died 15 months after onset of the disease.

Pseudo gray platelet syndrome in a patient with acute myocardial infarction.

We report a patient with pseudo gray platelet syndrome. He was admitted to our hospital because of acute myocardial infarction. He had platelets that were stained poorly and appeared gray and agranular under a light microscope. This appearance is a characteristic feature of gray platelet syndrome. However, in this case, no bleeding tendency was observed and the abnormality was dependent on the presence of ethylenediamine tetra acetic acid (EDTA) and did not occur in a nonanticoagulant, trisodium citrate dihydrate and heparin. There are few reports of this pseudo gray platelet syndrome and, in fact, this is the first report of the syndrome in Japan, possibly because the phenomenon has been unrecognized and passed over in the past.

[Multiple myeloma (IgG-kappa) infiltrating central nervous system, lymph nodes, liver, and kidneys, and with elevation of IgE].

A 63-year-old man was admitted because of general malaise, fever, headache, generalized lymphadenopathy and hepatomegaly in July 2002. He was diagnosed as having multiple myeloma (MM) (IgG-kappa type) with atypical plasma cells in the bone marrow, lymph nodes and cerebrospinal fluid. Systemic and intrathecal chemotherapy were effective. Because of an increase of polyclonal IgE, electrophoretic patterns revealed an M-peak which was not as sharp as that in IgG myeloma. IgE production is not impaired by the pathologic process in MM patients.

[Coexistence of pure red cell aplasia and autoimmune hemolytic anemia occurring during remission of malignant lymphoma].

A 56-year-old woman was admitted because of anemia in April 2001. A diagnosis of malignant lymphoma (ML) (diffuse mixed, B-cell type) had been made in March 2000 whereafter she had been treated with CHOP chemotherapy and had achieved complete remission (CR). On examination, it was found she had concurrently developed pure red cell aplasia (PRCA) and warm type autoimmune hemolytic anemia (AIHA) without relapse of the ML. The PRCA and AIHA were successfully treated with prednisolone. To our knowledge, only 4 cases of PRCA and AIHA associated with ML have been reported. Moreover, this is the first report of the coexistence of PRCA and AIHA occurring during the CR of ML.

[Autologous peripheral blood stem cell transplantation for Japanese multiple myeloma patients: results of a feasibility study].

A feasibility study on high-dose therapy with autologous peripheral blood stem cell transplantation (HDT/PBSCT) was performed in Japanese patients with multiple myeloma (MM). Twenty evaluable patients younger than 65 years old with stage II/III MM were enrolled in this study. Three courses of VAD were used as initial chemotherapy. High-dose etoposide or cyclophosphamide followed by G-CSF was used for PBSCH, and 1.2-89.3 (median 23.4) x 106/kg of CD34+ cells were collected. Single (11 patients) or tandem (9 patients) HDT with melphalan (MEL) 200 mg/m2 or MEL 140 mg/m2 plus TBI 10 Gy were performed. The incidence of grade 4 toxicity (COG) was 10% and treatment-related mortality was 5%. Complete response and tumor reduction of more than 75% were obtained in 4 (21%) and 16 (84%) out of 19 patients, respectively. The actuarial 3-year overall survival (OS) and event-free survival (EFS) after PBSCT/HDT were 65.6% and 22.0%, respectively. The median EFS duration was 18 months. These preliminary results indicated that HDT/PBSCT is feasible for Japanese MM patients. A prospective randomized clinical trial will be required to assess the efficacy.

Sequence of busulfan-induced neural progenitor cell damage in the fetal rat brain.

The sequence of neural progenitor cell (NPC) damage induced in fetal rat brain by transplacental exposure to busulfan, an antineoplastic bifunctional-alkylating agent, on gestational day 13 was examined by immunohistochemical and real-time RT-PCR analyses. Following busulfan treatment, pyknotic NPCs first appeared in the medial layer and then extended to the dorsal layer of the ventricular zone (VZ) of the telencephalon. Pyknotic NPCs that were immunohistochemically positive for cleaved caspase-3, i.e. apoptotic NPCs, began to increase at 24 h after treatment, peaked at 48 h, and returned to the control levels at 96 h. On the other hand, the index (%) of phospho-histone H3-positive NPCs, i.e. mitotic NPCs, and that of BrdU-positive NPCs, i.e. S-phase cells, decreased in accordance with the increase in the index of apoptotic NPCs. Prior to the peak time of apoptotic NPCs, the indices of p53- and p21-positive NPCs peaked at 36 h. In addition, the expression levels of p21 and Puma (p53-target genes) mRNAs were elevated in real-time RT-PCR analysis. These findings indicated that busulfan not only induced apoptosis through the p53-mediated intrinsic pathway but also inhibited cell proliferation in NPCs, resulting in a reduction of the width of the telencephalon. On the other hand, in spite of up-regulation of p21 expression, the expression of cyclin D1, part of the cell cycle machinery of the G1/S transition, and the expression levels of Cdc20 and cyclin B1 which are involved in G2/M transition, showed no changes, giving no possible information of busulfan-induced cell cycle arrest in NPCs.

Changes in auditory brainstem response (ABR) in Kanamycin-induced auditory disturbance model rats.

This study was designed to evaluate changes in auditory brainstem response (ABR) in the course of auditory disturbance in rats induced by Kanamycin (KM). KM was administered subcutaneously to 12 CD (SD) male rats aged 6 weeks for 10 days at a dose of 800 mg/kg. Death was observed in one male on day 8 and 2 males on day 10. It was thought that kidney damage was the cause of death from histopathological findings. ABR was recorded before KM treatment and on days 4, 8, 10 and 11 after KM treatment. The ABR changes after KM treatment in rats were as follows. On day 4, 6 rats showed an increase in amplitude of waves I and/or II and on day 8, among those, 4 rats still showed a high amplitude of waves I and/or II. On day 8, 2 rats showed an elevation of ABR threshold (15-40 dB SPL) and a decrease in amplitude of wave I and increase in amplitude of wave II at the same time. On day 11, 7 rats showed a decrease in amplitude of wave I. In addition, ABR threshold shifts (10-70 dB SPL) were observed in those rats. In ABR recording, KM-induced auditory disturbance model rats showed an increase in amplitude of waves I and/or II earlier than an ABR threshold shift. By analyzing temporal alteration of amplitude of the ABR components, we could detect precursory phenomenon of the auditory disturbance at an early phase of treatment. By following the pathway of click-ABR and tone pip-ABR examination, the auditory disturbance of low- frequency to high-frequency range could be analyzed at an early date in detail.

Amplification of IGH/CCND1 fusion gene in a primary plasma cell leukemia case.

The IGH/CCND1 fusion gene has been reported in many hematologic tumors such as mantle cell lymphoma, chronic lymphocytic leukemia, prolymphocytic leukemia, multiple myeloma, and plasma cell leukemia. We report a case of plasma cell leukemia showing five IGH/CCND1 fusion signals by interphase fluorescence in situ hybridization (FISH). Conventional cytogenetic analysis and multicolor spectral karyotyping showed a complex karyotype that did not include t(11;14). Metaphase FISH studies revealed three IGH/CCND1 fusion signals, two of which were amplified signals. These findings indicate that IGH/CCND1 fusion gene was amplified and interspersed in several chromosomes. The patient was treated with intensive chemotherapy. However, the clinical course was very aggressive. The amplification of the IGH/CCND1 fusion gene may contribute to the aggressive course of the disease. To our knowledge, this is the first case showing amplification of the IGH/CCND1 gene in plasma cell neoplasms.

The cytoskeleton-dependent localization of cdc2/cyclin B in blastomere cortex during Xenopus embryonic cell cycle.

In the early development of the frog, Xenopus laevis, blastomeres undergo synchronous divisions at about the 12th cell cycle, followed by asynchronous divisions, which is referred to as mid-blastula transition (MBT). We investigated the distribution of several regulating factors for cell cycles around MBT using immunocytochemistry and confocal fluorescence microscopy. At the 8th cell cycle, most of the cdc2/cyclin B was localized in the cortical cytoplasm throughout the cell cycle, in the centrosomes and the nucleus at interphase and prometaphase, and in the spindles at metaphase and anaphase. Cdc2 was also localized in the chromatins at metaphase and anaphase. Cyclin B1 mRNA was localized in the periphery of the nucleus, but not in the cell cortex. At the 13th cell cycle, the amount of cdc2/cyclin B in the cortical cytoplasm decreased, and the inactive form of cdc2, phosphorylated at tyrosine 15, appeared in the nucleus and the centrosomes at interphase, indicating that the regulation of cdc2 by phosphorylation occurs around MBT. When the blastomeres were treated with nocodazole or latrunculin A at the 8th cell cycle, the amount of cortical cdc2 decreased, but that of cyclin B did not change. The cortical localization of cdc2 is dependent upon both microtubules and microfilaments. Most of the cdc27 was localized in the centrosomes, and in the spindle poles, but no significant difference was observed between the 8th and the 13th cell cycles. It is possible that the cortical MPF activity is regulated by the differential localization between cdc2 and cyclin B.