High concentrations of immunoreactive inhibin in the plasma of mares and fetal gonads during the second half of pregnancy

Plasma concentrations of immunoreactive (ir)-inhibin were measured in seven pregnant mares from around Day 140 of gestation to Day 2 after parturition using a heterologous bovine-based radioimmunoassay (RIA). Concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), oestradiol-17 beta, progesterone and relaxin were also measured in the same samples. A marked increase in plasma concentrations of ir-inhibin, FSH and LH occurred between Day 220 and Day 300 of gestation but the concentrations of all three hormones returned to baseline by about Day 320 (three weeks before parturition). In contrast, circulating concentrations of the three placental hormones, oestradiol-17 beta, progesterone and relaxin, increased during the final weeks of pregnancy and then decreased markedly to basal values within two days of parturition. There was a positive correlation between circulating concentrations of ir-inhibin and FSH (r = 0.75, P < 0.01) rather than the expected negative correlation. ir-inhibin was not detected in homogenates obtained at Day 190 of pregnancy and form term placenta, but high concentrations of ir-inhibin were present in homogenates of fetal and newborn gonads. Despite the high concentrations of ir-inhibin in these homogenates, they failed to exert any suppressive bioactivity on FSH secretion by rat pituitary cells cultured in vitro. Furthermore, immunohistochemical staining revealed the presence of inhibin in the interstitial cells of equine fetal gonads at Day 190 of gestation. These findings demonstrate for the first time that high concentrations of ir-inhibin, LH and FSH are secreted into the peripheral circulation of the mare during the second half of pregnancy. However, ir-inhibin present in the plasma of pregnant mares appears to be biologically inactive. This hormone is not presumed to be of placental origin but it is proposed that either the enlarged fetal gonads or the maternal ovaries, or both of these organs, may be a source of inhibin in response to the coincident increase in circulating concentrations of LH and FSH.

Fibrous hamartoma of the tongue: report of a case with immunohistochemical and ultrastructural studies

The case of an 8-month-old female with fibrous hamartoma of the tongue is reported with immunohistochemical and electron microscopic findings. An elastic hard mass at the base of the tongue gradually enlarged, causing dysphagia. The tumor was excised by CO2 laser. Under light microscopy, the tumor was observed as composed of fibroblast-like cells, fibrocollagenous bundles and striated muscle tissues. The majority of the cells were immunoreactive for vimentin. Electronmicroscopically, they contained numerous intermediate filaments, some had intercellular microvilli and cilia (9 + 2 type). These findings revealed that the cells of the fibrous hamartoma in our case may possess both mesenchymal and epithelial properties.

Nasal natural killer (NK) cell lymphoma: report of a case with activated NK cells containing Epstein-Barr virus and expressing CD21 antigen, and comparative studies of their phenotype and cytotoxicity with normal NK cells

Malignant lymphomas arising from the nasal cavity have been considered to be derived from T cells, but recent surface marker studies suggest that more than half of the lymphomas are derived from natural killer (NK) cells. Here we describe a case of nasal lymphoma whose lymphoma cells were identified as NK cells by morphological, phenotypic, immunogenotypic, and functional studies. We believe this is the first study with functional evidence of NK activity. When compared with normal freshly isolated NK cells or activated NK cells, the surface phenotypes and NK activity of the patient tumour cells were those of the activated, but not resting, NK cells. Also, Epstein-Barr virus (EBV) was detected in the tumour cells and the lymphoma cells were found to be monoclonally expanded. The patient's lymphoma cells also expressed EBV receptor CD21 (CR2) and CD30 (Ki-1) that have not been described on normal NK cells. We therefore examined highly enriched NK cells of normal donors, and found that some resting and/or activated NK cells express these antigens.

Acinic cell tumour of the maxillary sinus: an unusual case initially diagnosed as parotid cancer

An unusual case of acinic cell tumour of the maxillary sinus is presented. The patient, a 41-year-old male who had undergone incomplete excision of the tumour in the left parotid region previously, was referred to our department for further treatment. The initial pathological diagnosis was adenocarcinoma of the parotid gland. CT-scan not only revealed tumours in the left pre-auricular and upper neck region, but also an enhanced mass in the left maxillary sinus. Although there were neither nasal symptoms nor destruction of the maxillary bone, aspiration biopsy of the maxillary sinus revealed class V. Total maxillectomy, radiotherapy and systemic chemotherapy were performed just after total parotidectomy and radical neck dissection at the left side. The clinical and histopathological findings are discussed.

Age-related morphometrical changes of arteries of uterine wall in mares

To investigate the morphological changes of uterine wall arteries associated with the progression of age in Thoroughbred broodmares, uterine wall arteries from 13 mares, aged 2 to 31 years, were studied by routine histomorphometry. The ratio of intimal thickness to external diameter increased due to hyperplasia of elastic fibers and was significantly correlated with age (r = 0.95, P < 0.001). The ratio of medial thickness to external diameter decreased and was also significantly correlated with age (r = -0.84, P < 0.001). Using electron microscopy, it was determined that the cross-sectional area of the tunica media occupied by smooth muscle cells gradually decreased with increasing age. These results demonstrate that in arteries of the uterine wall in mares, hyperplasia of intimal elastic fiber and thinning of the medial smooth muscular layer is associated with aging, suggesting that aging may influence endometrial pathology.

E2A-HLF-mediated cell transformation requires both the trans-activation domains of E2A and the leucine zipper dimerization domain of HLF

The E2A-HLF fusion gene, formed by the t(17;19)(q22;p13) translocation in childhood acute pro-B-cell leukemia, encodes a hybrid protein that contains the paired trans-activation domains of E2A (E12/E47) linked to the basic region/leucine zipper DNA-binding and dimerization domain of hepatic leukemia factor (HLF). To assess the transforming potential of this novel gene, we introduced it into NIH 3T3 murine fibroblasts by using an expression vector that also contained the neomycin resistance gene. Cells selected for resistance to the neomycin analog G418 formed aberrant colonies in monolayer cultures, marked by increased cell density and altered morphology. Transfected cells also grew readily in soft agar, producing colonies whose sizes correlated with E2A-HLF expression levels. Subclones expanded from colonies with high levels of the protein reproducibly formed tumors in nude mice and grew to higher plateau-phase cell densities in reduced-serum conditions than did parental NIH 3T3 cells. By contrast, NIH 3T3 cells expressing mutant E2A-HLF proteins that lacked either of the bipartite E2A trans-activation domains or the HLF leucine zipper domain failed to show oncogenic properties, including anchorage-independent cell growth. Thus, both of the E2A trans-activation motifs and the HLF leucine zipper dimerization domain are essential for the transforming potential of the chimeric E2A-HLF protein, suggesting a model in which aberrant regulation of the expression pattern of downstream target genes contributes to leukemogenesis.

Subepithelial fiber components of the round window membrane of the guinea pig: an ultrastructural and immunohistochemical study

Subepithelial fiber components of the round window membrane (RWM) of the guinea pig were studied by the following methods: transmission electron microscopy (TEM), scanning electron microscopy (SEM) with NaOH treatment, high-voltage electron microscopy (HVEM) and immunohistochemical staining. SEM observation revealed intersecting collagen fibers and a vascular network in the middle layer. TEM observation showed that at the attachment region to the bone fibroblasts, collagen fibers and elastic fibers were intermingled with each other, and mesenchymal cells (bone-lining cells) were scattered on the surface of the bone. The cytoplasmic processes of fibroblasts and bone-lining cells were connected by interdigitations. HVEM demonstrated that collagen fibers of the RWM were directly linked to the fibers of the bone matrix. Immunohistochemically, the middle layer was positive for antibody to type I collagen. Immunoreaction for fibronectin was also positive at the middle layer and most intense in the region attached to the bone. Thus, the RWM is securely attached to the bone by type I collagen fibers together with the bone-lining cells and fibroblasts.

Ultrastructure and three-dimensional imaging of epimyoepithelial islands in benign lymphoepithelial lesions

Benign lymphoepithelial lesions of the salivary glands associated with Sjögren's syndrome are characterized by extensive infiltration of lymphoid cells, atrophy of acini and the presence of so-called epimyoepithelial islands. This report describes ultrastructural and three-dimensional reconstructive studies of epimyoepithelial islands performed at Tokyo Women's Medical College. Ultrastructural examination showed that these islands are composed mainly of epithelial cells containing intermediate filaments and/or tonofilament bundles, scattered lymphocytes and plasma cells. Myoepithelium-like cells containing myofilaments were sometimes found in the peripheral portion of the myoepithelial islands. Also, mitotic figures were rarely found in these islands. Three-dimensional reconstructive study revealed that the epimyoepithelial islands are not isolated cell clusters but are continuous hypertrophic duct-like structures. These results suggest that the epimyoepithelial islands are derived from proliferating duct epithelial cells, especially those of large peripheral ducts.

Carcinoma ex pleomorphic adenoma of the soft palate

A case of carcinoma ex pleomorphic adenoma arising in the soft palate is reported. The tumour presented had enlarged gradually over 10 years and finally occupied the oral cavity. The patient was admitted to our hospital due to disturbance of her speech and swallowing, and a sudden haemorrhage from the tumour. The initial pathological diagnosis by open biopsy was benign pleomorphic adenoma. After total resection, histological examination revealed that the tumour was composed partly of benign pleomorphic adenoma and partly of an adenocarcinomatous component. The carcinoma cells with prominent nucleoli were spheroid or polygonal in shape, and frequently formed ductal structures with areas of necrosis. Mitoses were also found. These findings showed that this tumour was a secondary carcinoma which had developed in a preexisting pleomorphic adenoma.

[A neuroendocrinological study on the mechanism of feeding-associated circadian rhythm of plasma corticosterone and feeding behaviour in rats: a role of neuropeptide Y in the paraventricular nucleus]

Plasma corticosterone (CORT) level in rats increases before meal (pre-feeding peak), when rats are subjected to restricted daily feeding (RF), in which food is supplied only at a fixed time of day. Corticotropin-releasing hormones (CRH) release is also suggested to increase prior to meal. Cell bodies of CRH neurons exist in the paraventricular nucleus (PVN) which receives neuropeptide Y (NPY) containing neurons of two different origins: one from the brainstem, in which catecholamine (CA) coexists, and the other from the arcuate nucleus (ARC). The aim of the present study is to examine the role of NPY neurons from the brainstem in feeding and CRH secretion. To accomplish this aim, NPY in the discrete areas of brain and in the extracellular space of the PVN were measured under ad-lib feeding, food deprivation, and RF, together with plasma CORT level. Under ad-lib feeding, NPY in the PVN didn't variate throughout the day. The extracellular NPY in the PVN, however, increased under food deprivation, which decreased rapidly after refeeding, and increased just before the daily meal under RF. And this preprandial increase reappeared by 3 day food deprivation even after RF was terminated and replaced by ad-lib feeding for 7 days. The preprandial increase was suppressed by 6-hydroxy-dopamine (6-OHDA), a CA deprivator, injected into the PVN or the ascending bundle of noradrenaline fibers. It is concluded that, (1) the NPY neurons in the PVN aren't involved in the regulation of plasma CORT level and feeding behavior under ad-lib feeding, but involved under food deprivation, (2) the prefeeding increase of the extracellular NPY in the PVN is an expression of a feeding-associated circadian oscillation under RF. By contrast, the prandial decrease in the extracellular NPY is a result of food intake, (3) the noradrenergic neurons innervating the PVN are important for the expression of the prefeeding NPY peak under RF.

Myelodysplasia and acute myeloid leukaemia in cases of aplastic anaemia and congenital neutropenia following G-CSF administration

Myelodysplasia and acute myeloid leukaemia (MDS/AML) developed in three cases of severe aplastic anaemia (SAA) and one case of congenital neutropenia (CN, Kostmann's disease) who received recombinant human granulocyte colony-stimulating factor (G-CSF) are reported. In these four MDS/AML cases, age at diagnosis of SAA/CN was 0-13 years, the cumulative dose of G-CSF was 98 micrograms/kg to 10 mg/kg over 1-57 months, and the interval from initiation of G-CSF to MDS/AML was 25, 23, 31 and 57 months, respectively. These results suggest a link between SAA/CN and MDS/AML in relation to G-CSF administration; however, large studies are necessary to determine if such a risk is significant in patients with SAA/CN who are treated with G-CSF.

Ultrastructural and immunocytochemical study of the subepithelial fiber component of the guinea pig inner ear

The connective tissues of the lateral cochlear wall and semicircular canal of the guinea pig were investigated by transmission electron microscopy, intermediate voltage electron microscopy and immunocytochemistry. In the spiral ligament, numerous fibroblasts and fiber bundles were intermingled with each other. Fibroblasts and fibers were also observed in the semicircular canal. Ultrastructurally, immuno-gold particles, indicating the presence of type II collagen, were found on the fibers in the spiral ligament and the semicircular canals. The present results revealed that both stria vascularis and the membranous semicircular canal were supported by a network of fibroblasts and type II collagen fibers.

Ultrastructural and immunohistochemical study of salivary duct carcinoma of the parotid gland

A case of salivary duct carcinoma of the parotid gland found in an 81-year-old man was studied by light microscopy, immunohistochemistry, and electron microscopy. Histologically, the tumor was composed of elongated cords of cells and ductal structure with desmoplastic stromal reaction. Tumor cell nests sometimes showed central comedonecrosis. Immunohistochemically, the tumor cells were positive for cytokeratin and epithelial membrane antigen, and they were negative for S-100 protein and muscle-specific actin. Electromicroscopically, two cell types were identified. The first cell type showed electron-lucent cytoplasm with scant organelles. The second type cell contained numerous mitochondria. Neither acinar nor myoepithelial cell differentiation was observed. These findings suggest that salivary duct carcinoma originates from the interlobular or excretory ducts.

Jasmonate-inducible expression of a potato cathepsin D inhibitor-GUS gene fusion in tobacco cells

A potato gene encoding cathepsin D inhibitor (CDI) is expressed constitutively in tubers and flower buds and it is inducible in leaves upon wounding of the tissue or by treatment with methyl jasmonate (MJA). A fusion gene (CDI:GUS) in which the 2.4 kb long promoter of the CDI gene was translationaly fused with the coding sequence for beta-glucuronidase (GUS) showed MJA-inducible expression in transformed tobacco cells in suspension. The maximum level of induction by MJA was obtained in the absence of auxin and repression of MJA-inducible expression of the fusion gene by auxin was released by aphidicolin, the results suggesting that MJA-inducible expression is repressed during active cell division. JA and MJA showed similar activities in inducing the expression of the fusion gene, while other JA-related compounds such as cucurbic acid, tuberonic acid and dihydrojasmonic acid neither induced expression of the fusion gene nor inhibited the MJA-inducible expression of the fusion gene. Methyl dihydrojasmonate specifically stimulated the MJA-inducible expression of the fusion gene. The MJA-inducible expression of the fusion gene was observed even with a 100 bp long promoter of the CDI gene albeit with significantly decreased level of expression compared to the 2.4 kb long promoter. The 100 bp long CDI promoter did not contain a G-box or hexamer motif that had been implicated in the MJA-responsive expression of several other plant genes. Further mutagenesis of the 100 bp long promoter by deletion or oligonucleotide insertion suggested that although a sequence between -100 and -82 is required for the MJA-responsive expression, the presence of this sequence alone does not confer the MJA-responsive expression.

[Nasal NK-cell lymphoma]

A 75-year-old man was admitted to our hospital on June 1st, 1993, because of nasal obstruction, epistaxis, fever, night sweats and weight loss. Examination disclosed a 2-cm white necrotic mass in the nasal septum, and a biopsy disclosed non-Hodgkin's lymphoma, diffuse, mixed-type. Imprint smears showed cytoplasmic azurophilic granules in the tumor cells. Dense granules were demonstrated by electron microscopy. The tumor cells were CD1-2+3-4-7+8-16+56+57-, and T cell receptor genes were in germline configuration. NK activity against K562 was strongly positive. Based on morphologic, phenotypic, immunogenotypic, and cytotoxic findings, the tumor cells seemed to be derived from activated NK cells. Because the tumor cells were positive for the EB virus and CD21 antigen, EB virus seemed to have infected CD21-positive NK cells and transformed them. MDR P-glycoprotein was also positive. This finding may explain why nasal lymphomas are resistant to chemotherapy and have a poor prognosis.

Effect of recombinant human granulocyte-colony stimulation factor (rhG-CSF) on immune system in pediatric patients with aplastic anemia

To determine the effect of recombinant human granulocyte-colony stimulation factor (rhG-CSF) on the immune system, serum immunoglobulins, lymphocyte subsets, and serum cytokines were analyzed in eight pediatric patients with aplastic anemia (AA) during 8-week rhG-CSF therapy. The rhG-CSF was administered either subcutaneously (200 micrograms/m2 x 4 weeks, followed by 400 micrograms/m2 x 4 weeks) or intravenously (400 micrograms/m2 x 4 weeks, followed by 800 micrograms/m2 x 4 weeks). In response to rhG-CSF therapy, neutrophil counts exceeded the pretreatment counts by twofold during the first week except for one case that did not attain twofold increase until day 41. While serum IgG and IgA were not affected, serum IgM was elevated during treatment in six of the eight cases to more than 1.2-fold basal levels (P < 0.04); however, there was no increase in serum interleukin (IL)-6 and interferon-gamma levels. On the other hand, CD56 positive NK cells significantly dropped from 7.7% to 4.5% (P < 0.02). These results indicate that systemic administration of rhG-CSF affects not only the neutrophil count, but also serum IgM levels and the natural killer cell population in patients with AA.

Prefeeding increase in paraventricular NE release is regulated by a feeding-associated rhythm in rats

Extracellular norepinephrine (NE) in the vicinity of the paraventricular nucleus was continuously measured over 24 h by means of in vivo microdialysis in rats under restricted daily feeding and ad libitum feeding. A 24-h rhythm in plasma corticosterone was monitored in separate rats under identical conditions. Under ad libitum feeding, the paraventricular NE showed a 24-h rhythm with lower levels in the light period and higher levels in the dark period. The temporal pattern was not affected by food deprivation for 3 days. The circadian peak of paraventricular NE lagged slightly behind that of plasma corticosterone under ad libitum feeding. On the other hand, when rats were fed for 2 h at a fixed time of day for 3 wk, the NE rhythm was changed and showed a major peak just before daily meals. To examine the nature of the prefeeding NE peak, a 24-hour variation of paraventricular NE was measured in rats under food deprivation that had been subjected to restricted daily feeding for 3 wk and subsequently to ad libitum feeding for 7 days. The paraventricular NE was high around the time when meal had been supplied under restricted daily feeding and low in the dark period. Similar changes were observed in plasma corticosterone. The findings indicate that the prefeeding increase in the paraventricular NE release is regulated by a feeding-associated circadian rhythm manifest in rats under restricted daily feeding.

Preparation and characterization of monoclonal antibodies against equine chondrocytes, osteoblasts and osteocytes

Three monoclonal antibodies capable of individually recognizing chondrocytes, osteoblasts and osteocytes were prepared. EB-1 reacted with a 55-kDa antigen on the chondrocyte membrane, EB-2 with a 110-kDa antigen on the membrane of osteoblasts and/or partial osteocytes, and EB-3 with a 130-kDa antigen on the membrane of osteocytes. These monoclonal antibodies may be useful probes for studying the differentiation and maturation of osteogenic cells.

Effect of gentamycin on vestibular dark cells and melanocytes: an ultrastructural and cytochemical study

Vestibular dark cells areas in gentamycin (GM)-intoxicated guinea pigs were examined ultrastructurally and cytochemically. After GM treatment the dark cells represented cytoplasmic vacuoles, wide intercellular space, less osmiophilic cytoplasm and irregularly shaped basal portions. Cytochemically, Na+,K(+)-ATPase activity was demonstrated on the basolateral folded plasma membranes of the dark cells similarly in both GM-intoxicated and control guinea pigs. These findings revealed that the dark cells still possessed a function of regulating the ionic composition of the endolymph, although they showed various structural changes. On the other hand, the melanocytes extended their cytoplasmic processes into the basement membrane and the intercellular space of the dark cells. Melanosomes markedly increased in number dose-dependently by GM treatment. The significance and the function of the melanocytes in the dark-cell areas are discussed.

Cervical neurofibroma in a patient with von Recklinghausen's disease

A case of a huge cervical neurofibroma associated with von Recklinghausen's disease is reported. The patient with von Recklinghausen's disease was a 48-year-old woman complaining of a rapidly growing mass around the neck for the last 6 months. In von Recklinghausen's disease, which corresponds to neurofibromatosis-I, gigantic tumors around the neck often occur. The present case was classified as a plexiform neurofibroma which is derived from the peripheral nervous system, and this type frequently shows malignant change in contrast to other types of neurofibroma. In general, it is difficult to determine the origin of the nerve in cervical neurofibromas. A total extirpation of the tumor was done in our case, and revealed the nerve of origin to be the vagal nerve. Pathologically, H-E stained specimens showed that the tumor was a benign neurofibroma. However, immunostaining of the majority of the tumor cells were positive for PCNA. These results suggest that the tumor of our case possessed a low malignant potential. To date, neither local recurrence nor distant metastasis has been found on subsequent examinations.

Embryonal rhabdomyosarcoma arising in the buccal mucosa: a case report with immunohistochemical and electronmicroscopic findings

Rhabdomyosarcoma is one of the most common soft-tissue neoplasms in children. We report a case of a 9-year-old female with embryonal rhabdomyosarcoma arising in the buccal region with immunohistochemical and electronmicroscopic findings. Under a light microscope, it was observed that the tumor was composed of small round or spindle-shaped cells with pleomorphic and hyperchromatic nuclei. They were immunoreactive for actin, myoglobin and desmin. With an electron microscope, it was found that most tumor cells contained filamentous structures and free ribosomes. Some of them showed typical myofilaments, M-bands and Z-lines. These findings were specific evidence of rhabdomyosarcoma. Twenty courses of VAC (vincristine, D-actinomycin and cyclophosphamide) chemotherapy were administered, followed by surgical resection of the tumor.

Second cutaneous neoplasms after acute lymphoblastic leukemia in childhood

Two cases of second cutaneous neoplasms, one with adenoid cystic carcinoma of the skin and the other with basal cell carcinoma, both occurring 7 years after treatment for childhood acute lymphoblastic leukemia (ALL) are reported. Although such cutaneous neoplasms are generally reported in patients over 40 years of age, our cases, which were diagnosed at the ages of 9 and 14, are the first report of the occurrence of such cutaneous neoplasms following ALL. The neoplasms arose from the scalp of two patients who had received cranial irradiation for central nervous system prophylaxis. The possible link between leukemia therapy incorporating irradiation and the pathogenesis of second cutaneous neoplasms in the scalp is discussed.

Establishment and characterization of a human neuroblastoma cell line derived from a brain metastatic lesion

We encountered a case of abdominal primary stage IV neuroblastoma which recurred in the central nervous system. A neuroblastoma cell line, designated KP-N-NS, was established from this brain metastatic lesion. This is considered to be the first neuroblastoma cell line established from a brain metastatic lesion. In culture, KP-N-NS exhibited N(neuroblastic) type cell morphology with neurite-like processes and small cell bodies. This cell line revealed karyotypic abnormality, 46, XX, -1, +der (1)t(1;?)(p36.1;?), and twelve-fold amplification of MYCN DNA (twice as much in primary bone marrow tumor cells). Integrin study indicated high expression levels of alpha 1 beta 1 and alpha 4 beta 1, but alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1, alpha 6 beta 1, alpha 6 beta 4, and alpha v beta 3 were barely detectable by fluorescence-activated cell sorting (FACS) analysis. Compared with 8 other previously established N-type neuroblastoma cell lines, no significantly characteristic integrin expression was detected in this cell line. KP-N-NS will provide a useful tool for the study of metastasis and relapse in the central nervous system in neuroblastoma patients.

Persistent adrenergic reinnervation of previously denervated muscle in cat

Synapse formation by aberrant nerves at chronically denervated intrinsic laryngeal muscles was observed even at 21 months after the transection of the recurrent laryngeal nerve in cats. Some of the aberrant nerves were adrenergic, and these nerve terminals were in synaptic contact with the postsynaptic membrane of the neuromuscular junctions together with non-adrenergic nerve terminals. Therefore, heterogeneous reinnervation between adrenergic nerve and muscle was found to be maintained for a long time.

Accelerated idioventricular rhythm in three newborn infants with congenital heart disease

Accelerated idioventricular rhythm was observed in three newborn infants with congenital heart disease. This ventricular arrhythmia in all of our patients did not alter the clinical features of the congenital heart disease, and it disappeared at the ages of 84 days, 40 days, and 45 days, respectively. This arrhythmia is generally considered to be benign, which also appears to be the case with the newborn infant with congenital heart disease.