Transient receptor potential channel m4 and m5 in magnocellular cells in rat supraoptic and paraventricular nuclei

The neurohypophysial hormones, vasopressin (VP) and oxytocin (OT), are synthesised by magnocellular cells in the supraoptic nucleus (SON) and the paraventricular nucleus (PVN) of the hypothalamus. The release of VP into the general circulation from the neurohypophysis increases during hyperosmolality, hypotension and hypovolaemia. VP neurones increase hormone release by increasing their firing rate as a result of adopting a phasic bursting. Depolarising after potentials (DAPs) following a series of action potentials are considered to be involved in the generation of the phasic bursts by summating to plateau potentials. We recently discovered a fast DAP (fDAP) in addition to the slower DAP characterised previously. Almost all VP neurones expressed the fDAP, whereas only 16% of OT neurones had this property, which implicates the involvement of fDAP in the generation of the firing patterns in VP neurones. Our findings obtained from electrophysiological experiments suggested that the ionic current underlying the fDAP is mediated by those of two closely-related Ca(2+) -activated cation channels: the melastatin-related subfamily of transient receptor potential channels, TRPM4 and TRPM5. In the present study, double/triple immunofluorescence microscopy and reverse transcriptase-polymerase chain reaction techniques were employed to evaluate whether TRPM4 and TRPM5 are specifically located in VP neurones. Using specific antibodies against these channels, TRPM5 immunoreactivity was found almost exclusively in VP neurones, but not in OT neurones in both the SON and PVN. The most prominent TRPM5 immunoreactivity was in the dendrites of VP neurones. By contrast, most TRPM4 immunoreactivity occurred in cell bodies of both VP and OT neurones. TRPM4 and TRPM5 mRNA were both found in a cDNA library derived from SON punches. These results indictate the possible involvement of TRPM5 in the generation of the fDAP, and these channels may play an important role in determining the distinct firing properties of VP neurones in the SON.

Enzymatic hydrolysis of 1,3-1,4-beta-glucosyl oligosaccharides by 1,3-1,4-beta-glucanase from Synechocystis PCC6803: a comparison with assays using polymer and chromophoric oligosaccharide substrates

The specificity of 1,3-1,4-beta-glucanase from Synechocystis PCC6803 (SsGlc) was investigated using novel substrates 1,3-1,4-beta-glucosyl oligosaccharides, in which 1,3- and 1,4-linkages are located in various arrangements. After the enzymatic reaction, the reaction products were separated and determined by high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). As a result, SsGlc was found to hydrolyze the pentasaccharides, which possess three contiguous 1,4-beta-glycosidic linkages (cellotetraose sequence) adjacent to 1,3-beta-linkage, but none of the other oligosaccharides were hydrolyzed. To further analyze the specificity, kinetic measurements were performed using polymeric substrates and 4-methylumbelliferyl derivatives of laminaribiose and cellobiose (1,3-beta-(Glc)(2)-MU and 1,4-beta-(Glc)(2)-MU). The k(cat)/K(m) value obtained for barley beta-glucan was considerably larger than that for lichenan, indicating that SsGlc prefers 1,3-1,4-beta-glucan possessing a larger amount of cellotetraose sequence. This is consistent with the data obtained for 1,3-1,4-beta-glucosyl oligosaccharides. However, the k(cat)/K(m) value obtained for 1,4-beta-(Glc)(2)-MU was considerably lower than that for 1,3-beta-(Glc)(2)-MU, suggesting inconsistency with the data obtained from the other natural substrates. It is likely that the kinetic data obtained from such chromophoric substrates do not always reflect the true enzymatic properties.

Beta-1,4-glucanase-like protein from the cyanobacterium Synechocystis PCC6803 is a beta-1,3-1,4-glucanase and functions in salt stress tolerance

In the present study, we characterized the gene (Cyanobase accession number slr0897) designated Ssglc encoding a beta-1,4-glucanase-like protein (SsGlc) from Synechocystis PCC6803. The deduced amino acid sequence for Ssglc showed a high degree of similarity to sequences of GH (glycoside hydrolase) family 9 beta-1,4-glucanases (cellulases) from various sources. Surprisingly, the recombinant protein obtained from the Escherichia coli expression system was able to hydrolyse barley beta-glucan and lichenan (beta-1,3-1,4-glucan), but not cellulose (beta-1,4-glucan), curdlan (beta-1,3-glucan), or laminarin (beta-1,3-1,6-glucan). A 1H-NMR analysis of the enzymatic products revealed that the enzyme hydrolyses the beta-1,4-glycosidic linkage of barley beta-glucan through an inverting mechanism. The data indicated that SsGlc was a novel type of GH9 glucanase which could specifically hydrolyse the beta-1,3-1,4-linkage of glucan. The growth of mutant Synechocystis cells in which the Ssglc gene was disrupted by a kanamycin-resistance cartridge gene was almost the same as that of the wild-type cells under continuous light (40 micromol of photons/m2 per s), a 12 h light (40 micromol of photons/m2 per s)/12 h dark cycle, cold stress (4 degrees C), and high light stress (200 micromol of photons/m2 per s). However, under salt stress (300-450 mM NaCl), growth of the Ssglc-disrupted mutant cells was significantly inhibited as compared with that of the wild-type cells. The Ssglc-disrupted mutant cells showed a decreased rate of O2 consumption and NaHCO3-dependent O2 evolution as compared with the wild-type cells under salt stress. Under osmotic stress (100-400 mM sorbitol), there was no difference in growth between the wild-type and the Ssglc-disrupted mutant cells. These results suggest that SsGlc functions in salt stress tolerance in Synechocystis PCC6803.

A practical approach to the clinical diagnosis of Ewing's sarcoma/primitive neuroectodermal tumour and other small round cell tumours sharing EWS rearrangement using new fluorescence in situ hybridisation probes for EWSR1 on formalin fixed, paraffin wax embedded tissue

BACKGROUND

Over 90% of Ewing's sarcoma/primitive neuroectodermal tumour (ES/PNET) cases have the t(11;22) chromosomal rearrangement, which is also found in other small round cell tumours, including desmoplastic small round cell tumour (DSRCT) and clear cell sarcoma (CCS). Although this rearrangement can be analysed by fluorescence in situ hybridisation (FISH) using routinely formalin fixed, paraffin wax embedded (FFPE) tissues when fresh or frozen tissues are not available, a sensitive and convenient detection method is needed for routine clinical diagnosis.

AIMS

To investigate the usefulness of newly developed probes for detecting EWS rearrangement resulting from chromosomal translocations using FISH and FFPE tissue in the clinical diagnosis of ES/PNET, DSRCT, and CCS.

METHODS

Sixteen ES/PNETs, six DSRCTs, and six CCSs were studied. Three poorly differentiated synovial sarcomas, three alveolar rhabdomyosarcomas, and three neuroblastomas served as negative controls. Interphase FISH analysis was performed on FFPE tissue sections with a commercially available EWSR1 (22q12) dual colour, breakapart rearrangement probe.

RESULTS

One fused signal and one split signal of orange and green, demonstrating rearrangement of the EWS gene, was detected in 14 of 16 ES/PNETs, all six DRSCTs, and five of six CCSs, but not in the negative controls.

CONCLUSIONS

Interphase FISH using this newly developed probe is sensitive and specific for detecting the EWS gene on FFPE tissues and is of value in the routine clinical diagnosis of ES/PNET, DSRCT, and CCS.

Primary chondrosarcoma arising in the parotid gland

We report an extremely rare case of chondrosarcoma arising in the left parotid gland in a 45-year-old man who complained of painless swelling of the postauricular region. Computed tomography revealed a well-circumscribed tumor in the parotid area with a rim of scattered calcification. Under the diagnosis of benign parotid tumor, the tumor mass was removed with adequate margin. Histologic features were consistent with a low-grade chondrosarcoma showing lobular growth but clearly separated from adjacent glandular tissue of the parotid gland. Entire examination of the tumor disclosed no component of pleomorphic adenoma. There has been no evidence of recurrence for 2 months after the operation. The current case indicates that the parotid gland could be the site of occurrence of de novo primary chondrosarcoma.

Apoptosis, bcl-2 expression and p53 accumulation in myelodysplastic syndrome, myelodysplastic-syndrome-derived acute myelogenous leukemia and de novo acute myelogenous leukemia

Apoptosis and its dysregulation have been implicated in dysplastic and ineffective hematopoiesis and the neoplastic transformation of bone marrow in myelodysplastic syndrome (MDS). To explore the role of apoptosis in hematological disorders, we examined the frequency of apoptotic cells by the in situ end labeling method in bone marrow specimens from 37 patients with MDS [refractory anemia (RA) 10 cases, RA with excess of blasts (RAEB) 27 cases including 12 cases with leukemic transformation], 12 patients with MDS-derived acute myelogenous leukemia (AML) and 13 patients with de novo AML. In addition, we investigated the relationship of apoptosis to the immunohistochemical expression of bcl-2 and p53 in these cases, and the association of apoptosis, bcl-2, and p53 with the leukemic evolution of MDS by examining sequential bone marrow samples of the same patient from the time of initial diagnosis to the time of overt leukemia. The percentage frequency of apoptotic cells was significantly greater in MDS (RA: 9.46 +/- 2.99%, m +/- SD; RAEB: 5. 60 +/- 3.09) as compared with those in MDS-derived AML (0.62 +/- 0. 37), de novo AML (0.28 +/- 0.11) and controls (1.00 +/- 0.59). On the other hand, the cases of RAEB with leukemic transformation exhibited a lower frequency of apoptotic cells and a higher frequency of bcl-2- and p53-positive cells than those without transformation. When the RAEB cases transformed to AML, the frequency of apoptotic cells was significantly reduced (2.96 +/- 1. 54 --> 0.62 +/- 0.37), while the frequencies of bcl-2-positive cells and p53-positive cells were greater (10.88 +/- 3.66 --> 30.54 +/- 7. 14, and 20.21 +/- 6.21 --> 32.34 +/- 14.71, respectively). In contrast to MDS-derived AML, over a half of de novo AML cases showed few p53-positive cells. These findings corroborate the earlier notion that apoptosis may play a substantial role in dysplastic and ineffective hematopoiesis in MDS. It is also suggested that the suppression of apoptosis associated with enhanced bcl-2 expression and p53 accumulation increases the probability of developing leukemia in MDS, and that oncogenetic development might be different between MDS-derived AML and de novo AML.

Lactoferrin inhibits Bacillus cereus growth and heme analogs recover its growth

The growth of Bacillus cereus was markedly inhibited by the addition of lactoferrin and was recovered by the addition of FeCl3. The growth inhibition was also reversed by the addition of erythrocytes and hemoglobin. B. cereus can use heme or heme-protein complex (hemoglobin-haptoglobin and hematin-albumin complexes) as iron sources in iron deficient conditions. Therefore, B. cereus uses these heme or heme-protein complexes to prevent the growth inhibition of lactoferrin in vivo.

Use of hemoglobin as an iron source by Bacillus cereus

The hemoglobin binding activity of Bacillus cereus cells was measured with fluoresceinisothiocyanate (FITC)-conjugated hemoglobin using flow cytometry. Growth of B. cereus was markedly inhibited by the addition of apo-transferrin. B. cereus could not use transferrin-bound iron as an iron source in serum. The growth inhibition was reversed by the addition of a FeCl3 solution, erythrocytes or hemoglobin. B. cereus released hemolysin; these findings suggested that the hemoglobin released from erythrocytes by B. cereus hemolysin binds to B. cereus and is thus used as an iron source.

Congenital oligodendroglioma: a case report of a 34th-gestational week fetus with immunohistochemical study and review of the literature

A case of congenital oligodendroglioma occurring in a 34th-gestational week fetus is reported. The tumor was necrotic, hemorrhagic, and gelatinous. It covered the basal part of the brain, and almost the entire cerebellum was replaced by the tumor. The tumor cells had small, round, hyperchromatic nuclei and watery clear cytoplasm, and were arranged in a paved or alveolar pattern. Immunohistochemically, S100 protein, myelin-basic protein, neuron-specific enolase and Leu 7 were weakly positive for the cytoplasm, but glial fibrilliary acidic protein, synaptophysin, neurofilament, desmin, and vimentin were negative. Many tumor cell nuclei were positive for mutant p53 protein, and the labeling index was 85%. But there was no genetic alteration in exons 4 to 9 of p53 gene from the peripheral blood. The apoptosis index was 1.5%. Considering the p53 labeling index and the apoptosis index together, this congenital oligodendroglioma may be regarded as potentially malignant despite the benign morphological features.

Immunohistochemical assessment of proliferative activity in mammary adenomyoepithelioma

AIMS

Two cases of adenomyoepithelioma of the breast were examined by immunohistochemistry to evaluate proliferative activity of epithelial and myoepithelial components.

METHODS AND RESULTS

The tumours showed a bicellular pattern of gland-forming epithelial cells and proliferative myoepithelial cells with clear cytoplasm. They showed foci of monotonous growth of myoepithelial cells devoid of glands with low mitotic rate (1-2/10 high-power fields) and mild cytological atypia. Immunohistochemically, the glandular cells were positive for epithelial membrane antigen, cytokeratin (KL-1 and CAM5.2) and carcinoembryonic antigen, whereas tumour cells with clear cytoplasm were reactive with muscle-specific actin (MSA), alpha smooth muscle actin, vimentin, and S100 protein but negative for desmin. Proliferative activities assessed by MIB-1 (Ki-67)/MSA positive cell index were greater in myoepithelial cells in both cases (19.2% and 17.7%) as compared to those in epithelial cells (MIB-1/CAM5.2 index: 10.2% and 9.5%).

CONCLUSIONS

These results might account for the previous findings that myoepithelial components predominate over the epithelial ones in an advanced stage of this tumour as well as in recurrent or metastatic lesions.

Fibril formation in the rough endoplasmic reticulum of lymphoma cells. A case report with histopathologic, immunohistochemical, electron and immunoelectron microscopic studies

Signet ring cell lymphoma (SRCL) is a relatively new and infrequently described entity, characterized by an intracytoplasmic mass displacing the nucleus at the periphery. We present here a case of a Japanese female aged 73 with a retroperitoneal mass diagnosed as SRCL at autopsy. The neoplastic lymphoid cells showing signet ring appearance, due to the displacement of the nucleus to one side by intracytoplasmic eosinophilic inclusions, were immunoreactive for LCA, L26 and lambda light chains but PAS-negative. A small number of tumor cell nuclei demonstrated proliferating cell nuclear antigen-positive, but signet ring cells were negative. Ultrastructural study disclosed that fibrillary, lamellar or homogenous materials within rough endoplasmic reticulum of the tumor cells were selectively labeled by gold particles to anti-lambda antibody. A periodicity of 20-25 nm was observed in the fibrillary inclusions arranged haphazardly. The morphologic appearances of the case and the differential diagnosis are preceded by a review of the literature.

Recurred Castleman's disease containing a fibrohistiocytic nodular lesion with vascular occlusion

A recurring case of Castleman's disease containing a fibrohistiocytic nodular lesion is presented. The recurred tumor was found in the mediastinum of a 40 year old Japanese female who had undergone the extirpation of a mediastinal tumor 18 years previously and had been suffering from rheumatoid arthritis 5 years after the initial removal. Microscopically, the present tumor and the initial removed tumor fulfilled the morphologic criteria for the hyaline-vascular type of Castleman's disease. A well-demarcated nodular lesion (1.5 cm in diameter) was located in the present tumor. It consisted of interlacing oval to short spindle-shaped cells positive for factor XIIIa and vimentin, merging with lymphocytes, plasma cells, macrophages and capillaries lined by swollen endothelial cells. Mitotic figures were not noted. Foci of hemorrhage and necrosis were also not detected. The stenosis or occlusion of the large vessels due to intimal fibrosis and medial hypertrophy was observed around the nodular lesion.

Multiple papillary adenomas of type II pneumocytes found in a 13-year-old boy with von Recklinghausen's disease

A case of multiple papillary adenomas of type II pneumocytes is reported. A 13-year-old boy with von Recklinghausen's disease had small nodular lesions in both lungs without symptoms. The biopsied lung contained greyish-white nodules ranging in size from 0.5 to 2 mm. Light microscopic examination revealed cuboidal to low columnar cells arranged in a papillary pattern. Elastic fibres were present in the tumour stroma. Electron microscopically, the cells had osmiophilic lamellar bodies in the cytoplasm and short microvilli along the free border. The tumour cells expressed immunoreactivity for epithelial membrane antigen and surfactant apoprotein antibodies. More than 6 years after open lung biopsy, the patient is well but small nodular shadows can still be identified.

An unusual heterotopia of pyloric glands of the stomach with inverted downgrowth

A rarely reported, large heterotopia of gastric glands in the submucosal layer of the stomach is observed in a 79 year old Japanese man with early gastric cancer. Histologically, it consists of marked hyperplasia of benign foveolar-type epithelia and tubular glands which instead of growing upwards grow downwards into the submucosa. Immunohistochemically, many gastrin-positive G cells are observed within it, indicating the existence of independent pyloric-type glands from the surrounding mucosa with intestinal metaplasia. Muscle actin-positive fascicles, derived from the muscularis mucosae, are demonstrated to branch into it and to encapsulate it. This result suggests that the present lesion may not represent a truly submucosal ectopic location, but an inverted downgrowth of the mucosa into the submucosa, thus resembling an inverted polyp of the colon. An awareness of this unique lesion is important in order that it not be mistaken for a submucosal extension of the primary adenocarcinoma.

Primary mesenchymal chondrosarcoma of the lung. A case report with immunohistochemical and ultrastructural studies

A case of primary pulmonary mesenchymal chondrosarcoma is reported. The tumor occurred first in the lower lobe of the right lung of a Japanese female aged 45. Three years after the first operation it metastasized to the upper lobe of the left lung. The tumors were highly cellular and composed of undifferentiated mesenchymal cells and interspersed islands of well-differentiated cartilaginous tissue. Immunohistochemistry failed to detect S-100 and vimentin in the undifferentiated cells. In contrast, Leu-7 and blood coagulation factor XIIIa were positive in these cells. Electron microscopically, undifferentiated mesenchymal cells had narrow cytoplasm with sparsity of organelles, but no intermediate-sized filaments were detected. In the transitional areas between undifferentiated cells and cartilaginous components, thin intracytoplasmic filaments were sometimes observed in the tumor cells. The differentiation toward cartilaginous cells of undifferentiated mesenchymal cells was suggested by immunohistochemistry and electron microscopy. This is the first case of mesenchymal chondrosarcoma occurring in the lung with long-term follow-up.

[An autopsy case of four primary cancers including malignant meningioma]

The authors describe an autopsy case of a 68-year-old man with four primary cancers diagnosed at autopsy including malignant meningioma, early esophageal cancer, early gastric cancer and lung cancer. Recently, the number of patients with four and five primary cancers has been increasing. According to the Annual of the Pathological Autopsy Cases in Japan, 156 cases were reported during 16 years from 1974 to 1989. In this series, cancers were detected most frequently in stomach, colon, lung, prostate, liver and esophagus. However, only two cases with four and five primary cancers including malignant meningioma were reported. Because occult cancers like prostatic cancers are unexpectedly diagnosed at autopsy, the incidence of four and five primary cancers including malignant meningioma seems to be higher when the central nervous system is examined more frequently at autopsy.

[Serious complications of intravesical bacillus Calmette-Guerin therapy in patients with bladder cancer]

Side effects and serious complications of intravesical bacillus Calmette-Guérin (BCG) therapy were reviewed in 120 patients with transitional cell carcinoma of the urinary bladder from October, 1983 to June, 1989 at Hirosaki University Hospital. As local side effects, 102 patients (85.0%) had bladder irritability with frequency and/or micturition pain, and 46 patients (38.3%) had hematopyuria. As systemic side effects, fever in 43 patients (35.8%), elevation of serum GOT, GPT in 9 patients (7.5%), and malaise in 3 patients (2.5%) were seen. Serious complications were observed in 7 patients. 4 patients had a severely contracted bladder with decreased compliance less than 50 ml, 2 patients had persistent arthritis and one patient had interstitial pneumonia. In all 4 patients with a contracted bladder partial cystectomy was performed before or after intravesical BCG therapy, and three of them received more than ten times instillation of BCG. It was suggested that contracted bladder most likely occurred after frequent BCG instillations in addition to decreased bladder compliance. Contracted bladder was irreversible in 2 patients. Histopathologically, there was marked fibrosis in the muscular layer of the bladder without tuberculous inflammatory changes. It might depend on the severity of fibrosis in the muscular layer whether contracted bladder was reversible or not. Persistent arthritis was nonspecific inflammation with negative culture results for mycobacteria in the joint fluid in 2 patients. In one patient with interstitial pneumonia, fiberoptic bronchoscopy with transbronchial lung biopsy demonstrated marked fibrosis of alveolar septums and increased lymphocyte count without tuberculous inflammatory changes. The pathogenesis of this complications is considered to be a hypersensitivity reaction to BCG.

Gastric submucosal tumours of neurogenic origin with neuroaxonal and Schwann cell elements

Twelve cases of gastric submucosal tumours, originally diagnosed as leiomyoma and leiomyosarcoma, were investigated by staining with the neurogenic markers S-100 and neuron specific enolase (NSE). Three cases were, in addition, studied by electron microscopy. The tumours stained negatively for desmin, indicating that they were not of smooth muscle origin. All stained positively for S-100 and NSE. The ultrastructural features in the cases examined by electron microscopy were reminiscent of autonomic nerve structures normally present in the gastric wall. These included fine cytoplasmic processes of Schwann cells, wrapped with complete or incomplete basement membranes, and structures analogous to post-ganglionic neuroaxonal components. These tumours appear to represent a distinct type of gastric neoplasm originating from autonomic nerve elements in the stomach wall. They are different from previously described schwannomas or neurofibromas. In some of the tumours, identifiably neural elements are relatively a minor component, and the majority of the tumour cells are of undetermined origin. It is suggested that these cells may be poorly differentiated, lacking their antigenic determinants specific to neural differentiation.