Genetic clinical markers of human neuroblastoma with special reference to N-myc oncogene: amplified or not amplified?--An overview

Neuroblastoma is the most common extracranial tumor in children, and cytogenetically, chromosome 1p deletions, extrachromosomal double minutes, and homogeneously staining regions (HSRs) are commonly observed in cell lines and in tumors in advanced stages. It is found that an HSR represents genomic amplification of N-myc, which plays a key role in determining the aggressiveness of neuroblastoma. However, stage IV neuroblastomas or cell lines which lack N-myc amplification are also progressive, and some of them show evidence of N-myc expression in terms of mRNA and/or N-Myc oncoprotein. It was recently shown that a small proximal locus mapped between 1p35-36.1 and 1p36.23 may function as a suppressor gene of N-myc amplification. In neuroblastoma, a pattern of diploidy is associated with rapid tumor growth and poor survival. Expression of bcl-2 proto-oncogene is strongly associated with unfavorable histology, while expressions of Ha-ras and trk-A proto-oncogenes indicate a favorable prognosis. trk-A proto-oncogene encodes a receptor for nerve growth factor. Genetic characteristics of neuroblastomas found by urinary catecholamine mass screening are also discussed.

Fracture of an alumina ceramic head in total hip arthroplasty

The authors have experienced a fracture in the ceramic head in a total hip arthroplasty in three cases. Two of these were comminuted and the other was a hair-line fissure. A foreign body, perhaps from the operation, existed between the neck of the stem and the head in two cases (one in a comminuted fracture and the other in the fissure fracture). The other case had no foreign body, and, judging from the serial radiographs, the fracture was probably caused by weight-bearing stress. Care must be taken during operation to avoid interposing any foreign body in the modular ceramic head total hip arthroplasty, and the weight-bearing stress factor must be considered as an indication for a ceramic head fracture in young active patients.

A toluene-tolerant mutant of Pseudomonas aeruginosa lacking the outer membrane protein F

The outer membrane protein profiles of a toluene-tolerant mutant, Pseudomonas aeruginosa, strain PAK103, were compared with those of its parent strain PAO1161. Protein F (OprF), the most abundant outer membrane protein in the parental strain PAO1161, was missing in the toluene-tolerant strain PAK103. The absence of OprF may lead to the loss of toluene diffusion across in the outer membrane of the mutant cells.

Cranioplasty with split-thickness calvarial bone

Cranioplasty with autogenous split-thickness calvarial bone was performed in 10 patients. Follow-up for a mean of 19 months (range 2-43 mos) showed satisfactory protection of the brain and cosmetic reconstruction. No serious complication was seen except in one patient with postoperative epidural abscess. Split-thickness calvarial bone graft is recommended in patients with previous infection or high risk of infection, in poorly vascularized recipient sites resulting from multiple operations or irradiation, and in younger patients aged more than 7 years.

[The detection of factors that may promote the hepatocyte proliferation in the serum of a patient with crow-fukase syndrome]

We reported a case of Crow-Fukase syndrome and examined the mechanism of hepatomegaly in Crow-Fukase syndrome. A 67-year-old woman was presented with polyneruopathy, hepatosplenomegaly, pericardial effusion and M proteinemia. On examination, all laboratory data and clinical symptoms were compatible with Crow-Fukase syndrome. The patient was treated with prednisolone and immunoadsorption plasmaphresis therapy. All the clinical manifestations including hepatomegaly gradually improved. In order to examine whether some factors that promote the prolifelation of hepatocyte may exist in the patient's serum, we cultured mouse hepatocyte in the presence of patient's or control serum together. Though the number of hepatocytes decreased after 2 days culture, the number of hepatocytes cultured with patient's serum in active disease stage remained significantly greater than of hepatocytes cultured with either control serum or patient's serum in healing stage. There were no abnormal pathological findings in biopsied liver. Liver suggesting that hepatomegaly was the results of normal hepatocytes proliferation. Taken together, these findings suggest there were some factors that may promote the proliferation of hepatocytes or may have protective effect of hepatocyte in patient's serum. Though the level of human hepatocyte growth factor (h-HGF) in patient's serum in active disease stage was slightly increased, hepatomegaly cannot be attributable solely to h-HGF. Organomegaly is one of the important symptoms of the Crow-Fukase syndrome, however, in so far as we are aware its mechanism is not examined. In this report it is suggested that several unknown factors other than h-HGF may contribute the hepatomegaly of the Crow-Fukase syndrome.

Reciprocal regulation by cyclic nucleotides of the differentiation of rat osteoblast-like cells and mineralization of nodules

The effects of cAMP and cGMP on the differentiation of osteoblast-like cells derived from rat calvariae and on the formation of bone in vitro were studied. Continuous culture of osteoblast-like cells in the presence of 8-bromo-cyclic AMP (8-Br-cAMP) resulted in the dose-related inhibition both of the synthesis of cellular alkaline phosphatase (ALPase), which is known as a marker of osteoblastic differentiation, and of the formation of mineralized nodules, which is a model of the formation of bone in vitro. By contrast, 8-bromo-cyclic GMP (8-Br-cGMP) promoted the synthesis of ALPase and the formation of mineralized nodules. Northern blot analysis revealed that these cyclic nucleotides modulated the steady-state levels of mRNAs for ALPase and osteocalcin, a bone-matrix protein that is specifically produced by osteoblast. The present results indicate that cAMP and cGMP act reciprocally to regulate osteoblastic differentiation and the subsequent formation of mineralized nodules.

70-kDa heat shock cognate protein interacts directly with the N-terminal region of the retinoblastoma gene product pRb. Identification of a novel region of pRb-mediating protein interaction

Retinoblastoma protein (pRb) functions as a tumor suppressor, and certain proteins are known to bind to pRb in the C-terminal region. Although the N-terminal region of pRb may also mediate interaction with some proteins, no such protein has been identified yet. We demonstrated previously the in vivo protein association between pRb and 73-kDa heat shock cognate protein (hsc73) in certain human tumor cell lines. In this report we analyzed the interaction between these two proteins in vitro. Our data showed that hsc73 interacts with the novel N-terminal region of pRb; that is, pRb binds directly to hsc73 and dissociates from hsc73 in an ATP-dependent manner. By using deletion mutants of cDNA encoding pRb, the hsc73 binding site of pRb was determined to be located in the region (residues 301-372) outside the so-called A pocket (residues 373-579) of this tumor suppressor protein. This finding was compatible with the fact that the adenovirus E1A oncoprotein, which is known to bind to the E2F binding pocket region of pRb, could not compete with hsc73 for the binding. Furthermore, phosphorylation of pRb by cyclin-dependent kinase inhibited the binding of pRb to hsc73. These data suggest that hsc73 may act exclusively as the molecular chaperone for nonphosphorylated pRb. As a result, hsc73 may function as a molecular stabilizer of nonphosphorylated pRb.

Intradural extramedullary ependymoma. A case report

STUDY DESIGN

The present study illustrates a rare case of ependymoma of the spinal cord.

OBJECTIVES

An encapsulated intradural extramedullary ependymoma of the cervicothoracic spinal cord in a 24-year old woman is reported.

SUMMARY OF BACKGROUND DATA

Ependymoma is a glial tumor arising in the central nervous system. Intradural extramedullary ependymoma of the spinal cord is rare, and two cases were reported previously.

METHODS

The woman presented with myelopathy below C6. Magnetic resonance imaging showed an intradural tumor from C4 to T3 and no other lesion in the central nervous system. At surgery, the extramedullary tumor apparently was not attracted to the spinal cord or dura mater. Gross total removal was easily achieved under the operating microscope.

RESULTS

Histologic examination revealed the encapsulated tumor as an anaplastic ependymoma. Almost complete neurologic recovery was obtained.

CONCLUSION

The encapsulated appearance, lack of an apparent attachment to the central nervous system, and absence of signs of the primary neoplastic process within the brain or spinal cord suggested that the tumor arose from ectopic ependymal cells.

[Immunohistochemical analysis of adhesion molecules in directional coronary atherectomy specimens]

Chronic inflammatory cells are key components in the progression of atherosclerotic plaques and restenosis after coronary angioplasty. Adhesion molecules are fundamental in inflammatory processes. Therefore, the distributions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM) were investigated in directional coronary atherectomy specimens obtained from 14 patients, in 6 with acute coronary syndromes (myocardial infarction and unstable angina within 1 month), 6 with old myocardial infarction and 2 with stable effort angina. There were eight primary lesions and six restenotic lesions. Atherectomy tissue fragments were snap frozen and cut into 4 microns thick cryostat sections for immunohistochemical staining by avidin-biotin complex immunoperoxidase techniques using adhesion molecule specific monoclonal antibodies BBIG-I1 (ICAM-1) and BBIG-V1 (VCAM). The cells of lesions were characterized in sequential sections by macrophage marker KP1 (CD68), endothelial marker JC/70A (CD31), and smooth muscle cell marker 1A4 (alpha-smooth muscle actin). Four restenotic lesions that had undergone a prior balloon angioplasty within a few months consisted of intimal proliferation and the other lesions were atherosclerotic plaque. Macrophage-rich areas were seen in the lesions from acute coronary syndromes and/or early restenotic lesions. Expression of ICAM-1 or VCAM was strongly associated with macrophage-rich areas, but VCAM staining was weaker than ICAM-1 except in one restenotic lesion. Macrophages that express ICAM-1 and/or VCAM may be important in the unstable plaques and restenotic lesions related to disease activity of ischemic heart disease.

[The detection of anti-cerebellar antibody western blot analysis in serum from a patient with Miller Fisher syndrome]

We here report a case of Miller Fisher syndrome (MFS) in which serum anti-cerebellar antibody was detected by Western blot analysis. The 32-year-old male studied suffered from diplopia, gait ataxia and sensory disturbance in the distal portion of the upper limbs preceded by cold-like symptoms. Neurological examination on admission revealed that he had external ophthalmoplegia with bilateral ptosis, cerebellar ataxia and areflexia. A cerebrospinal fluid examination showed albuminocytologic dissociation with a protein concentration of 60 mg/dl. Brain CT and MRI showed no significant abnormalities. The patient was diagnosed as MFS, and treated it with two sessions of immunoadsorption plasmapheresis (IAPP). After receiving IAPP therapy, the patient's neurological symptoms and signs were improved. Western blot analysis showed the existence of antibody directed against mouse cerebellum but not against mouse cerebrum, brain stem, and spinal cord in his serum, the level of which was decreased after the IAPP therapy. Serum anti-GQ1b antibody was also elevated. As far as we are aware, there have been no reports showing the existence of anti-cerebellar antibodies detected by Western blot analysis. Though the pathogenesis of MFS remains unclear, our findings suggest that anti-cerebellar antibody detected by Western blot analysis may be caused by cerebellar ataxia in MFS.

Isolation and characterization of a peptide isomerase from funnel web spider venom

A novel peptide isomerase was purified from the venom of funnel web spider, Agelenopsis aperta. The complete primary structure of the isomerase has been established by sequence analyses of polypeptide chains, assignments of disulfide bridges, carbohydrate analyses, and mass spectrometry of sugar chains. The isomerase was found to be a 29-kDa polypeptide that consists of an 18-residue light chain and a 243-residue heavy chain connected by a single disulfide bridge. The heavy chain contains three intramolecular disulfide bridges and one N-linked oligosaccharide chain with a simple trimannosyl core structure. A sequence homology search showed a significant similarity of the enzyme with serine proteases, particularly around a putative catalytic triad of the isomerase. The isomerase specifically interconverts the configuration of Ser46 of a 48-amino-acid peptide, omega-agatoxin-TK, and the conversion rate from L-Ser to D-Ser was approximately two times faster than the reverse reaction.

Degradation of polyaromatic hydrocarbons by organic solvent-tolerant bacteria from deep sea

We isolated three organic solvent (OS)-tolerant bacterial strains DS-1051, DS-1902, and DS-313 from a depth of 1,168 m in Sagami Bay, Japan. These isolates were tolerant to various kinds of toxic OSs such as benzene, toluene, and p-xylene. They also could degrade polyaromatic hydrocarbons, naphthalene or biphenyl, in a medium-OS (9:1) two-liquid-phase system. Percentage degradation of polyaromatic hydrocarbons in OS by these strains were higher than those obtained from cultures in which substrates were in the medium without OS.

[A patient with a relapse of myasthenia gravis after a 13-year remission following successful treatment by mediastinal irradiation and corticosteroid therapy]

We report a patient with myasthenia gravis who experienced a relapse 13 years after apparently successful treatment by mediastinal irradiation and corticosteroid therapy. A 20-year-old male was admitted to Shinshu University Hospital with a chief complain double vision and drooping eyelids. These symptoms had appeared 2 months prior to admission. They tended to be more severe late in the day, and varied from day to day. Prior to this admission the patient had been healthy for the 13 years since undergoing 45-Gy mediastinal irradiation and corticosteroid therapy. MRI and CT studies revealed no thymic hyperplasia. Total thymectomy was performed, and his myasthenic symptoms, including the opthalmoplegia, improved. Histological examination of the resected thymus revealed an active thymus with germinal centers. Immunohistological studies showed an abundance of intracellular adhesion molecule-1 (ICAM-1) in the germinal centers and thymic medullary epithelium, and the presence of lymphoid function-associated antigen-1 (LFA-1) in thymic lymphocytes. ICAM-1 and LFA-1 are ligand of adhesion molecules which interact with each other and play an important role in antigen presentation. Acetylcholine receptor (ACh-R) antigen is known to be present in the thymus. The presence of both ICAM-1 and LFA-1 in the active thymus in this patient suggests that these adhesion molecules may have a role in ACh-R antigen presentation, causing myasthenia. These findings suggest that patients with myasthenia gravis who do not undergo total thymectomy have a risk of recurrence, even after long-term remission.

Binding of myosin and its subfragment-1 with antibodies specific to the two heads of the myosin molecule

It was shown by Miyanishi et al. [Miyanishi, T., Maita, T., Matsuda, G., and Tonomura, Y. (1982) J. Biochem. 91, 1845-1853] that the amino acid sequence around the reactive lysine residue is different between head B (Pi-burst head) and head A of the myosin molecule. Thus, we synthesized these two peptides, and prepared rabbit polyclonal antibodies against them. Each antibody bound strongly with both peptides. However, the binding of the antibodies with S-1 was inhibited by the peptide used for the antigen but unaffected by the non-antigen peptide, suggesting that only antibodies specific to each head can bind with S-1. Myosin was absorbed by either antibody A or B, which was immobilized on protein A in Staphylococcus aureus cells. However, half of S-1 was absorbed by each of the antibodies. The S-1 prepared showed about 0.5 mol of initial Pi-liberation per mol of S-1. The Pi-burst size of S-1 unbound to the immobilized anti-A antibody increased to almost 1 mol/mol S-1, while that of S-1 unbound to the anti-B antibody decreased to 0.15 mol/mol S-1. These results suggest the existence of two kinds of heads in the myosin molecule.

[Comparative study of the efficacy of plasma exchange, immunoadsorption plasmapheresis and corticosteroid administration in the treatment of Guillain-Barré syndrome]

We have retrospectively compared the efficacy of plasma exchange (PE), immunoadsorption plasmapheresis therapy (IAPP), corticosteroid administration and no treatment in the treatment of the Guillain-Barré Syndrome (GBS). Forty-two patients with GBS and clinical functional grades of more than Hughes 3 were admitted to Shinshu University Hospital, Nagano Red-cross Hospital and Saku General Hospital between 1978 and 1994. These patients were treated with either PE, IAPP, corticosteroids or no therapy. Eight were treated with PE, eleven with IAPP, twelve with corticosteroids and eleven were untreated. None of the patients were received combined therapy. The four groups of patients were compared on the following points; duration of the deteliocation in symptoms, duration of the worst symptoms, period of the ability to walk after onset, minimum motor nerve conduction velocity (MCV) over the course, maximum cerebrospinal fluid (CSF) protein concentration over the course, and CSF protein concentration improvement 6 weeks after onset as compared with 2 weeks after onset. The results revealed that the duration of the worst symptoms was shortened more in the IAPP-treated and PE-treated groups than in the other groups. Decreases in CSF protein concentration were more significant in the IAPP-treated and PE-treated groups than in the other groups. There were no significant differences in the other parameters among the groups. Furthermore the clinical symptoms of GBS improved more rapidly with PE and IAPP than with supportive care alone or corticosteroid therapy, especially in the early phase of the disease. IAPP and PE are equally effective.(ABSTRACT TRUNCATED AT 250 WORDS)